fs/ext4/super.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/ext4/super.c
   4  *
   5  * Copyright (C) 1992, 1993, 1994, 1995
   6  * Remy Card (card@masi.ibp.fr)
   7  * Laboratoire MASI - Institut Blaise Pascal
   8  * Universite Pierre et Marie Curie (Paris VI)
   9  *
  10  *  from
  11  *
  12  *  linux/fs/minix/inode.c
  13  *
  14  *  Copyright (C) 1991, 1992  Linus Torvalds
  15  *
  16  *  Big-endian to little-endian byte-swapping/bitmaps by
  17  *        David S. Miller (davem@caip.rutgers.edu), 1995
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/string.h>
  22 #include <linux/fs.h>
  23 #include <linux/time.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/slab.h>
  26 #include <linux/init.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/backing-dev.h>
  29 #include <linux/parser.h>
  30 #include <linux/buffer_head.h>
  31 #include <linux/exportfs.h>
  32 #include <linux/vfs.h>
  33 #include <linux/random.h>
  34 #include <linux/mount.h>
  35 #include <linux/namei.h>
  36 #include <linux/quotaops.h>
  37 #include <linux/seq_file.h>
  38 #include <linux/ctype.h>
  39 #include <linux/log2.h>
  40 #include <linux/crc16.h>
  41 #include <linux/dax.h>
  42 #include <linux/cleancache.h>
  43 #include <linux/uaccess.h>
  44 #include <linux/iversion.h>
  45
  46 #include <linux/kthread.h>
  47 #include <linux/freezer.h>
  48
  49 #include "ext4.h"
  50 #include "ext4_extents.h"       /* Needed for trace points definition */
  51 #include "ext4_jbd2.h"
  52 #include "xattr.h"
  53 #include "acl.h"
  54 #include "mballoc.h"
  55 #include "fsmap.h"
  56
  57 #define CREATE_TRACE_POINTS
  58 #include <trace/events/ext4.h>
  59
  60 static struct ext4_lazy_init *ext4_li_info;
  61 static struct mutex ext4_li_mtx;
  62 static struct ratelimit_state ext4_mount_msg_ratelimit;
  63
  64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  65                              unsigned long journal_devnum);
  66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  67 static int ext4_commit_super(struct super_block *sb, int sync);
  68 static void ext4_mark_recovery_complete(struct super_block *sb,
  69                                         struct ext4_super_block *es);
  70 static void ext4_clear_journal_err(struct super_block *sb,
  71                                    struct ext4_super_block *es);
  72 static int ext4_sync_fs(struct super_block *sb, int wait);
  73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  75 static int ext4_unfreeze(struct super_block *sb);
  76 static int ext4_freeze(struct super_block *sb);
  77 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  78                        const char *dev_name, void *data);
  79 static inline int ext2_feature_set_ok(struct super_block *sb);
  80 static inline int ext3_feature_set_ok(struct super_block *sb);
  81 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  82 static void ext4_destroy_lazyinit_thread(void);
  83 static void ext4_unregister_li_request(struct super_block *sb);
  84 static void ext4_clear_request_list(void);
  85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  86                                             unsigned int journal_inum);
  87
  88 /*
  89  * Lock ordering
  90  *
  91  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  92  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  93  *
  94  * page fault path:
  95  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  96  *   page lock -> i_data_sem (rw)
  97  *
  98  * buffered write path:
  99  * sb_start_write -> i_mutex -> mmap_sem
 100  * sb_start_write -> i_mutex -> transaction start -> page lock ->
 101  *   i_data_sem (rw)
 102  *
 103  * truncate:
 104  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 105  *   i_mmap_rwsem (w) -> page lock
 106  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 107  *   transaction start -> i_data_sem (rw)
 108  *
 109  * direct IO:
 110  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> mmap_sem
 111  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) ->
 112  *   transaction start -> i_data_sem (rw)
 113  *
 114  * writepages:
 115  * transaction start -> page lock(s) -> i_data_sem (rw)
 116  */
 117
 118 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 119 static struct file_system_type ext2_fs_type = {
 120         .owner          = THIS_MODULE,
 121         .name           = "ext2",
 122         .mount          = ext4_mount,
 123         .kill_sb        = kill_block_super,
 124         .fs_flags       = FS_REQUIRES_DEV,
 125 };
 126 MODULE_ALIAS_FS("ext2");
 127 MODULE_ALIAS("ext2");
 128 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 129 #else
 130 #define IS_EXT2_SB(sb) (0)
 131 #endif
 132
 133
 134 static struct file_system_type ext3_fs_type = {
 135         .owner          = THIS_MODULE,
 136         .name           = "ext3",
 137         .mount          = ext4_mount,
 138         .kill_sb        = kill_block_super,
 139         .fs_flags       = FS_REQUIRES_DEV,
 140 };
 141 MODULE_ALIAS_FS("ext3");
 142 MODULE_ALIAS("ext3");
 143 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 144
 145 static int ext4_verify_csum_type(struct super_block *sb,
 146                                  struct ext4_super_block *es)
 147 {
 148         if (!ext4_has_feature_metadata_csum(sb))
 149                 return 1;
 150
 151         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 152 }
 153
 154 static __le32 ext4_superblock_csum(struct super_block *sb,
 155                                    struct ext4_super_block *es)
 156 {
 157         struct ext4_sb_info *sbi = EXT4_SB(sb);
 158         int offset = offsetof(struct ext4_super_block, s_checksum);
 159         __u32 csum;
 160
 161         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 162
 163         return cpu_to_le32(csum);
 164 }
 165
 166 static int ext4_superblock_csum_verify(struct super_block *sb,
 167                                        struct ext4_super_block *es)
 168 {
 169         if (!ext4_has_metadata_csum(sb))
 170                 return 1;
 171
 172         return es->s_checksum == ext4_superblock_csum(sb, es);
 173 }
 174
 175 void ext4_superblock_csum_set(struct super_block *sb)
 176 {
 177         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 178
 179         if (!ext4_has_metadata_csum(sb))
 180                 return;
 181
 182         es->s_checksum = ext4_superblock_csum(sb, es);
 183 }
 184
 185 void *ext4_kvmalloc(size_t size, gfp_t flags)
 186 {
 187         void *ret;
 188
 189         ret = kmalloc(size, flags | __GFP_NOWARN);
 190         if (!ret)
 191                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 192         return ret;
 193 }
 194
 195 void *ext4_kvzalloc(size_t size, gfp_t flags)
 196 {
 197         void *ret;
 198
 199         ret = kzalloc(size, flags | __GFP_NOWARN);
 200         if (!ret)
 201                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 202         return ret;
 203 }
 204
 205 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 206                                struct ext4_group_desc *bg)
 207 {
 208         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 209                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 210                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 211 }
 212
 213 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 214                                struct ext4_group_desc *bg)
 215 {
 216         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 217                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 218                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 219 }
 220
 221 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 222                               struct ext4_group_desc *bg)
 223 {
 224         return le32_to_cpu(bg->bg_inode_table_lo) |
 225                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 226                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 227 }
 228
 229 __u32 ext4_free_group_clusters(struct super_block *sb,
 230                                struct ext4_group_desc *bg)
 231 {
 232         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 233                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 234                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 235 }
 236
 237 __u32 ext4_free_inodes_count(struct super_block *sb,
 238                               struct ext4_group_desc *bg)
 239 {
 240         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 241                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 242                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 243 }
 244
 245 __u32 ext4_used_dirs_count(struct super_block *sb,
 246                               struct ext4_group_desc *bg)
 247 {
 248         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 249                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 250                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 251 }
 252
 253 __u32 ext4_itable_unused_count(struct super_block *sb,
 254                               struct ext4_group_desc *bg)
 255 {
 256         return le16_to_cpu(bg->bg_itable_unused_lo) |
 257                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 258                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 259 }
 260
 261 void ext4_block_bitmap_set(struct super_block *sb,
 262                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 263 {
 264         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 265         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 266                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 267 }
 268
 269 void ext4_inode_bitmap_set(struct super_block *sb,
 270                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 271 {
 272         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 273         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 274                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 275 }
 276
 277 void ext4_inode_table_set(struct super_block *sb,
 278                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 279 {
 280         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 281         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 282                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 283 }
 284
 285 void ext4_free_group_clusters_set(struct super_block *sb,
 286                                   struct ext4_group_desc *bg, __u32 count)
 287 {
 288         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 289         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 290                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 291 }
 292
 293 void ext4_free_inodes_set(struct super_block *sb,
 294                           struct ext4_group_desc *bg, __u32 count)
 295 {
 296         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 297         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 298                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 299 }
 300
 301 void ext4_used_dirs_set(struct super_block *sb,
 302                           struct ext4_group_desc *bg, __u32 count)
 303 {
 304         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 305         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 306                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 307 }
 308
 309 void ext4_itable_unused_set(struct super_block *sb,
 310                           struct ext4_group_desc *bg, __u32 count)
 311 {
 312         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 313         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 314                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 315 }
 316
 317
 318 static void __save_error_info(struct super_block *sb, const char *func,
 319                             unsigned int line)
 320 {
 321         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 322
 323         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 324         if (bdev_read_only(sb->s_bdev))
 325                 return;
 326         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 327         es->s_last_error_time = cpu_to_le32(get_seconds());
 328         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 329         es->s_last_error_line = cpu_to_le32(line);
 330         if (!es->s_first_error_time) {
 331                 es->s_first_error_time = es->s_last_error_time;
 332                 strncpy(es->s_first_error_func, func,
 333                         sizeof(es->s_first_error_func));
 334                 es->s_first_error_line = cpu_to_le32(line);
 335                 es->s_first_error_ino = es->s_last_error_ino;
 336                 es->s_first_error_block = es->s_last_error_block;
 337         }
 338         /*
 339          * Start the daily error reporting function if it hasn't been
 340          * started already
 341          */
 342         if (!es->s_error_count)
 343                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 344         le32_add_cpu(&es->s_error_count, 1);
 345 }
 346
 347 static void save_error_info(struct super_block *sb, const char *func,
 348                             unsigned int line)
 349 {
 350         __save_error_info(sb, func, line);
 351         ext4_commit_super(sb, 1);
 352 }
 353
 354 /*
 355  * The del_gendisk() function uninitializes the disk-specific data
 356  * structures, including the bdi structure, without telling anyone
 357  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 358  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 359  * This is a kludge to prevent these oops until we can put in a proper
 360  * hook in del_gendisk() to inform the VFS and file system layers.
 361  */
 362 static int block_device_ejected(struct super_block *sb)
 363 {
 364         struct inode *bd_inode = sb->s_bdev->bd_inode;
 365         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 366
 367         return bdi->dev == NULL;
 368 }
 369
 370 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 371 {
 372         struct super_block              *sb = journal->j_private;
 373         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 374         int                             error = is_journal_aborted(journal);
 375         struct ext4_journal_cb_entry    *jce;
 376
 377         BUG_ON(txn->t_state == T_FINISHED);
 378
 379         ext4_process_freed_data(sb, txn->t_tid);
 380
 381         spin_lock(&sbi->s_md_lock);
 382         while (!list_empty(&txn->t_private_list)) {
 383                 jce = list_entry(txn->t_private_list.next,
 384                                  struct ext4_journal_cb_entry, jce_list);
 385                 list_del_init(&jce->jce_list);
 386                 spin_unlock(&sbi->s_md_lock);
 387                 jce->jce_func(sb, jce, error);
 388                 spin_lock(&sbi->s_md_lock);
 389         }
 390         spin_unlock(&sbi->s_md_lock);
 391 }
 392
 393 /* Deal with the reporting of failure conditions on a filesystem such as
 394  * inconsistencies detected or read IO failures.
 395  *
 396  * On ext2, we can store the error state of the filesystem in the
 397  * superblock.  That is not possible on ext4, because we may have other
 398  * write ordering constraints on the superblock which prevent us from
 399  * writing it out straight away; and given that the journal is about to
 400  * be aborted, we can't rely on the current, or future, transactions to
 401  * write out the superblock safely.
 402  *
 403  * We'll just use the jbd2_journal_abort() error code to record an error in
 404  * the journal instead.  On recovery, the journal will complain about
 405  * that error until we've noted it down and cleared it.
 406  */
 407
 408 static void ext4_handle_error(struct super_block *sb)
 409 {
 410         if (sb_rdonly(sb))
 411                 return;
 412
 413         if (!test_opt(sb, ERRORS_CONT)) {
 414                 journal_t *journal = EXT4_SB(sb)->s_journal;
 415
 416                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 417                 if (journal)
 418                         jbd2_journal_abort(journal, -EIO);
 419         }
 420         if (test_opt(sb, ERRORS_RO)) {
 421                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 422                 /*
 423                  * Make sure updated value of ->s_mount_flags will be visible
 424                  * before ->s_flags update
 425                  */
 426                 smp_wmb();
 427                 sb->s_flags |= SB_RDONLY;
 428         }
 429         if (test_opt(sb, ERRORS_PANIC)) {
 430                 if (EXT4_SB(sb)->s_journal &&
 431                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 432                         return;
 433                 panic("EXT4-fs (device %s): panic forced after error\n",
 434                         sb->s_id);
 435         }
 436 }
 437
 438 #define ext4_error_ratelimit(sb)                                        \
 439                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 440                              "EXT4-fs error")
 441
 442 void __ext4_error(struct super_block *sb, const char *function,
 443                   unsigned int line, const char *fmt, ...)
 444 {
 445         struct va_format vaf;
 446         va_list args;
 447
 448         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 449                 return;
 450
 451         if (ext4_error_ratelimit(sb)) {
 452                 va_start(args, fmt);
 453                 vaf.fmt = fmt;
 454                 vaf.va = &args;
 455                 printk(KERN_CRIT
 456                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 457                        sb->s_id, function, line, current->comm, &vaf);
 458                 va_end(args);
 459         }
 460         save_error_info(sb, function, line);
 461         ext4_handle_error(sb);
 462 }
 463
 464 void __ext4_error_inode(struct inode *inode, const char *function,
 465                         unsigned int line, ext4_fsblk_t block,
 466                         const char *fmt, ...)
 467 {
 468         va_list args;
 469         struct va_format vaf;
 470         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 471
 472         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 473                 return;
 474
 475         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 476         es->s_last_error_block = cpu_to_le64(block);
 477         if (ext4_error_ratelimit(inode->i_sb)) {
 478                 va_start(args, fmt);
 479                 vaf.fmt = fmt;
 480                 vaf.va = &args;
 481                 if (block)
 482                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 483                                "inode #%lu: block %llu: comm %s: %pV\n",
 484                                inode->i_sb->s_id, function, line, inode->i_ino,
 485                                block, current->comm, &vaf);
 486                 else
 487                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 488                                "inode #%lu: comm %s: %pV\n",
 489                                inode->i_sb->s_id, function, line, inode->i_ino,
 490                                current->comm, &vaf);
 491                 va_end(args);
 492         }
 493         save_error_info(inode->i_sb, function, line);
 494         ext4_handle_error(inode->i_sb);
 495 }
 496
 497 void __ext4_error_file(struct file *file, const char *function,
 498                        unsigned int line, ext4_fsblk_t block,
 499                        const char *fmt, ...)
 500 {
 501         va_list args;
 502         struct va_format vaf;
 503         struct ext4_super_block *es;
 504         struct inode *inode = file_inode(file);
 505         char pathname[80], *path;
 506
 507         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 508                 return;
 509
 510         es = EXT4_SB(inode->i_sb)->s_es;
 511         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 512         if (ext4_error_ratelimit(inode->i_sb)) {
 513                 path = file_path(file, pathname, sizeof(pathname));
 514                 if (IS_ERR(path))
 515                         path = "(unknown)";
 516                 va_start(args, fmt);
 517                 vaf.fmt = fmt;
 518                 vaf.va = &args;
 519                 if (block)
 520                         printk(KERN_CRIT
 521                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 522                                "block %llu: comm %s: path %s: %pV\n",
 523                                inode->i_sb->s_id, function, line, inode->i_ino,
 524                                block, current->comm, path, &vaf);
 525                 else
 526                         printk(KERN_CRIT
 527                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 528                                "comm %s: path %s: %pV\n",
 529                                inode->i_sb->s_id, function, line, inode->i_ino,
 530                                current->comm, path, &vaf);
 531                 va_end(args);
 532         }
 533         save_error_info(inode->i_sb, function, line);
 534         ext4_handle_error(inode->i_sb);
 535 }
 536
 537 const char *ext4_decode_error(struct super_block *sb, int errno,
 538                               char nbuf[16])
 539 {
 540         char *errstr = NULL;
 541
 542         switch (errno) {
 543         case -EFSCORRUPTED:
 544                 errstr = "Corrupt filesystem";
 545                 break;
 546         case -EFSBADCRC:
 547                 errstr = "Filesystem failed CRC";
 548                 break;
 549         case -EIO:
 550                 errstr = "IO failure";
 551                 break;
 552         case -ENOMEM:
 553                 errstr = "Out of memory";
 554                 break;
 555         case -EROFS:
 556                 if (!sb || (EXT4_SB(sb)->s_journal &&
 557                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 558                         errstr = "Journal has aborted";
 559                 else
 560                         errstr = "Readonly filesystem";
 561                 break;
 562         default:
 563                 /* If the caller passed in an extra buffer for unknown
 564                  * errors, textualise them now.  Else we just return
 565                  * NULL. */
 566                 if (nbuf) {
 567                         /* Check for truncated error codes... */
 568                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 569                                 errstr = nbuf;
 570                 }
 571                 break;
 572         }
 573
 574         return errstr;
 575 }
 576
 577 /* __ext4_std_error decodes expected errors from journaling functions
 578  * automatically and invokes the appropriate error response.  */
 579
 580 void __ext4_std_error(struct super_block *sb, const char *function,
 581                       unsigned int line, int errno)
 582 {
 583         char nbuf[16];
 584         const char *errstr;
 585
 586         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 587                 return;
 588
 589         /* Special case: if the error is EROFS, and we're not already
 590          * inside a transaction, then there's really no point in logging
 591          * an error. */
 592         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
 593                 return;
 594
 595         if (ext4_error_ratelimit(sb)) {
 596                 errstr = ext4_decode_error(sb, errno, nbuf);
 597                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 598                        sb->s_id, function, line, errstr);
 599         }
 600
 601         save_error_info(sb, function, line);
 602         ext4_handle_error(sb);
 603 }
 604
 605 /*
 606  * ext4_abort is a much stronger failure handler than ext4_error.  The
 607  * abort function may be used to deal with unrecoverable failures such
 608  * as journal IO errors or ENOMEM at a critical moment in log management.
 609  *
 610  * We unconditionally force the filesystem into an ABORT|READONLY state,
 611  * unless the error response on the fs has been set to panic in which
 612  * case we take the easy way out and panic immediately.
 613  */
 614
 615 void __ext4_abort(struct super_block *sb, const char *function,
 616                 unsigned int line, const char *fmt, ...)
 617 {
 618         struct va_format vaf;
 619         va_list args;
 620
 621         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 622                 return;
 623
 624         save_error_info(sb, function, line);
 625         va_start(args, fmt);
 626         vaf.fmt = fmt;
 627         vaf.va = &args;
 628         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 629                sb->s_id, function, line, &vaf);
 630         va_end(args);
 631
 632         if (sb_rdonly(sb) == 0) {
 633                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 634                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 635                 /*
 636                  * Make sure updated value of ->s_mount_flags will be visible
 637                  * before ->s_flags update
 638                  */
 639                 smp_wmb();
 640                 sb->s_flags |= SB_RDONLY;
 641                 if (EXT4_SB(sb)->s_journal)
 642                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 643                 save_error_info(sb, function, line);
 644         }
 645         if (test_opt(sb, ERRORS_PANIC)) {
 646                 if (EXT4_SB(sb)->s_journal &&
 647                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 648                         return;
 649                 panic("EXT4-fs panic from previous error\n");
 650         }
 651 }
 652
 653 void __ext4_msg(struct super_block *sb,
 654                 const char *prefix, const char *fmt, ...)
 655 {
 656         struct va_format vaf;
 657         va_list args;
 658
 659         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 660                 return;
 661
 662         va_start(args, fmt);
 663         vaf.fmt = fmt;
 664         vaf.va = &args;
 665         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 666         va_end(args);
 667 }
 668
 669 #define ext4_warning_ratelimit(sb)                                      \
 670                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 671                              "EXT4-fs warning")
 672
 673 void __ext4_warning(struct super_block *sb, const char *function,
 674                     unsigned int line, const char *fmt, ...)
 675 {
 676         struct va_format vaf;
 677         va_list args;
 678
 679         if (!ext4_warning_ratelimit(sb))
 680                 return;
 681
 682         va_start(args, fmt);
 683         vaf.fmt = fmt;
 684         vaf.va = &args;
 685         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 686                sb->s_id, function, line, &vaf);
 687         va_end(args);
 688 }
 689
 690 void __ext4_warning_inode(const struct inode *inode, const char *function,
 691                           unsigned int line, const char *fmt, ...)
 692 {
 693         struct va_format vaf;
 694         va_list args;
 695
 696         if (!ext4_warning_ratelimit(inode->i_sb))
 697                 return;
 698
 699         va_start(args, fmt);
 700         vaf.fmt = fmt;
 701         vaf.va = &args;
 702         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 703                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 704                function, line, inode->i_ino, current->comm, &vaf);
 705         va_end(args);
 706 }
 707
 708 void __ext4_grp_locked_error(const char *function, unsigned int line,
 709                              struct super_block *sb, ext4_group_t grp,
 710                              unsigned long ino, ext4_fsblk_t block,
 711                              const char *fmt, ...)
 712 __releases(bitlock)
 713 __acquires(bitlock)
 714 {
 715         struct va_format vaf;
 716         va_list args;
 717         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 718
 719         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 720                 return;
 721
 722         es->s_last_error_ino = cpu_to_le32(ino);
 723         es->s_last_error_block = cpu_to_le64(block);
 724         __save_error_info(sb, function, line);
 725
 726         if (ext4_error_ratelimit(sb)) {
 727                 va_start(args, fmt);
 728                 vaf.fmt = fmt;
 729                 vaf.va = &args;
 730                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 731                        sb->s_id, function, line, grp);
 732                 if (ino)
 733                         printk(KERN_CONT "inode %lu: ", ino);
 734                 if (block)
 735                         printk(KERN_CONT "block %llu:",
 736                                (unsigned long long) block);
 737                 printk(KERN_CONT "%pV\n", &vaf);
 738                 va_end(args);
 739         }
 740
 741         if (test_opt(sb, ERRORS_CONT)) {
 742                 ext4_commit_super(sb, 0);
 743                 return;
 744         }
 745
 746         ext4_unlock_group(sb, grp);
 747         ext4_commit_super(sb, 1);
 748         ext4_handle_error(sb);
 749         /*
 750          * We only get here in the ERRORS_RO case; relocking the group
 751          * may be dangerous, but nothing bad will happen since the
 752          * filesystem will have already been marked read/only and the
 753          * journal has been aborted.  We return 1 as a hint to callers
 754          * who might what to use the return value from
 755          * ext4_grp_locked_error() to distinguish between the
 756          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 757          * aggressively from the ext4 function in question, with a
 758          * more appropriate error code.
 759          */
 760         ext4_lock_group(sb, grp);
 761         return;
 762 }
 763
 764 void ext4_update_dynamic_rev(struct super_block *sb)
 765 {
 766         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 767
 768         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 769                 return;
 770
 771         ext4_warning(sb,
 772                      "updating to rev %d because of new feature flag, "
 773                      "running e2fsck is recommended",
 774                      EXT4_DYNAMIC_REV);
 775
 776         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 777         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 778         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 779         /* leave es->s_feature_*compat flags alone */
 780         /* es->s_uuid will be set by e2fsck if empty */
 781
 782         /*
 783          * The rest of the superblock fields should be zero, and if not it
 784          * means they are likely already in use, so leave them alone.  We
 785          * can leave it up to e2fsck to clean up any inconsistencies there.
 786          */
 787 }
 788
 789 /*
 790  * Open the external journal device
 791  */
 792 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 793 {
 794         struct block_device *bdev;
 795         char b[BDEVNAME_SIZE];
 796
 797         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 798         if (IS_ERR(bdev))
 799                 goto fail;
 800         return bdev;
 801
 802 fail:
 803         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 804                         __bdevname(dev, b), PTR_ERR(bdev));
 805         return NULL;
 806 }
 807
 808 /*
 809  * Release the journal device
 810  */
 811 static void ext4_blkdev_put(struct block_device *bdev)
 812 {
 813         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 814 }
 815
 816 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 817 {
 818         struct block_device *bdev;
 819         bdev = sbi->journal_bdev;
 820         if (bdev) {
 821                 ext4_blkdev_put(bdev);
 822                 sbi->journal_bdev = NULL;
 823         }
 824 }
 825
 826 static inline struct inode *orphan_list_entry(struct list_head *l)
 827 {
 828         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 829 }
 830
 831 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 832 {
 833         struct list_head *l;
 834
 835         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 836                  le32_to_cpu(sbi->s_es->s_last_orphan));
 837
 838         printk(KERN_ERR "sb_info orphan list:\n");
 839         list_for_each(l, &sbi->s_orphan) {
 840                 struct inode *inode = orphan_list_entry(l);
 841                 printk(KERN_ERR "  "
 842                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 843                        inode->i_sb->s_id, inode->i_ino, inode,
 844                        inode->i_mode, inode->i_nlink,
 845                        NEXT_ORPHAN(inode));
 846         }
 847 }
 848
 849 #ifdef CONFIG_QUOTA
 850 static int ext4_quota_off(struct super_block *sb, int type);
 851
 852 static inline void ext4_quota_off_umount(struct super_block *sb)
 853 {
 854         int type;
 855
 856         /* Use our quota_off function to clear inode flags etc. */
 857         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 858                 ext4_quota_off(sb, type);
 859 }
 860 #else
 861 static inline void ext4_quota_off_umount(struct super_block *sb)
 862 {
 863 }
 864 #endif
 865
 866 static void ext4_put_super(struct super_block *sb)
 867 {
 868         struct ext4_sb_info *sbi = EXT4_SB(sb);
 869         struct ext4_super_block *es = sbi->s_es;
 870         int aborted = 0;
 871         int i, err;
 872
 873         ext4_unregister_li_request(sb);
 874         ext4_quota_off_umount(sb);
 875
 876         destroy_workqueue(sbi->rsv_conversion_wq);
 877
 878         if (sbi->s_journal) {
 879                 aborted = is_journal_aborted(sbi->s_journal);
 880                 err = jbd2_journal_destroy(sbi->s_journal);
 881                 sbi->s_journal = NULL;
 882                 if ((err < 0) && !aborted)
 883                         ext4_abort(sb, "Couldn't clean up the journal");
 884         }
 885
 886         ext4_unregister_sysfs(sb);
 887         ext4_es_unregister_shrinker(sbi);
 888         del_timer_sync(&sbi->s_err_report);
 889         ext4_release_system_zone(sb);
 890         ext4_mb_release(sb);
 891         ext4_ext_release(sb);
 892
 893         if (!sb_rdonly(sb) && !aborted) {
 894                 ext4_clear_feature_journal_needs_recovery(sb);
 895                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 896         }
 897         if (!sb_rdonly(sb))
 898                 ext4_commit_super(sb, 1);
 899
 900         for (i = 0; i < sbi->s_gdb_count; i++)
 901                 brelse(sbi->s_group_desc[i]);
 902         kvfree(sbi->s_group_desc);
 903         kvfree(sbi->s_flex_groups);
 904         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 905         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 906         percpu_counter_destroy(&sbi->s_dirs_counter);
 907         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 908         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
 909 #ifdef CONFIG_QUOTA
 910         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 911                 kfree(sbi->s_qf_names[i]);
 912 #endif
 913
 914         /* Debugging code just in case the in-memory inode orphan list
 915          * isn't empty.  The on-disk one can be non-empty if we've
 916          * detected an error and taken the fs readonly, but the
 917          * in-memory list had better be clean by this point. */
 918         if (!list_empty(&sbi->s_orphan))
 919                 dump_orphan_list(sb, sbi);
 920         J_ASSERT(list_empty(&sbi->s_orphan));
 921
 922         sync_blockdev(sb->s_bdev);
 923         invalidate_bdev(sb->s_bdev);
 924         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 925                 /*
 926                  * Invalidate the journal device's buffers.  We don't want them
 927                  * floating about in memory - the physical journal device may
 928                  * hotswapped, and it breaks the `ro-after' testing code.
 929                  */
 930                 sync_blockdev(sbi->journal_bdev);
 931                 invalidate_bdev(sbi->journal_bdev);
 932                 ext4_blkdev_remove(sbi);
 933         }
 934         if (sbi->s_ea_inode_cache) {
 935                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
 936                 sbi->s_ea_inode_cache = NULL;
 937         }
 938         if (sbi->s_ea_block_cache) {
 939                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
 940                 sbi->s_ea_block_cache = NULL;
 941         }
 942         if (sbi->s_mmp_tsk)
 943                 kthread_stop(sbi->s_mmp_tsk);
 944         brelse(sbi->s_sbh);
 945         sb->s_fs_info = NULL;
 946         /*
 947          * Now that we are completely done shutting down the
 948          * superblock, we need to actually destroy the kobject.
 949          */
 950         kobject_put(&sbi->s_kobj);
 951         wait_for_completion(&sbi->s_kobj_unregister);
 952         if (sbi->s_chksum_driver)
 953                 crypto_free_shash(sbi->s_chksum_driver);
 954         kfree(sbi->s_blockgroup_lock);
 955         fs_put_dax(sbi->s_daxdev);
 956         kfree(sbi);
 957 }
 958
 959 static struct kmem_cache *ext4_inode_cachep;
 960
 961 /*
 962  * Called inside transaction, so use GFP_NOFS
 963  */
 964 static struct inode *ext4_alloc_inode(struct super_block *sb)
 965 {
 966         struct ext4_inode_info *ei;
 967
 968         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 969         if (!ei)
 970                 return NULL;
 971
 972         inode_set_iversion(&ei->vfs_inode, 1);
 973         spin_lock_init(&ei->i_raw_lock);
 974         INIT_LIST_HEAD(&ei->i_prealloc_list);
 975         spin_lock_init(&ei->i_prealloc_lock);
 976         ext4_es_init_tree(&ei->i_es_tree);
 977         rwlock_init(&ei->i_es_lock);
 978         INIT_LIST_HEAD(&ei->i_es_list);
 979         ei->i_es_all_nr = 0;
 980         ei->i_es_shk_nr = 0;
 981         ei->i_es_shrink_lblk = 0;
 982         ei->i_reserved_data_blocks = 0;
 983         ei->i_da_metadata_calc_len = 0;
 984         ei->i_da_metadata_calc_last_lblock = 0;
 985         spin_lock_init(&(ei->i_block_reservation_lock));
 986 #ifdef CONFIG_QUOTA
 987         ei->i_reserved_quota = 0;
 988         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 989 #endif
 990         ei->jinode = NULL;
 991         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 992         spin_lock_init(&ei->i_completed_io_lock);
 993         ei->i_sync_tid = 0;
 994         ei->i_datasync_tid = 0;
 995         atomic_set(&ei->i_unwritten, 0);
 996         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 997         return &ei->vfs_inode;
 998 }
 999
1000 static int ext4_drop_inode(struct inode *inode)
1001 {
1002         int drop = generic_drop_inode(inode);
1003
1004         trace_ext4_drop_inode(inode, drop);
1005         return drop;
1006 }
1007
1008 static void ext4_i_callback(struct rcu_head *head)
1009 {
1010         struct inode *inode = container_of(head, struct inode, i_rcu);
1011         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1012 }
1013
1014 static void ext4_destroy_inode(struct inode *inode)
1015 {
1016         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1017                 ext4_msg(inode->i_sb, KERN_ERR,
1018                          "Inode %lu (%p): orphan list check failed!",
1019                          inode->i_ino, EXT4_I(inode));
1020                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1021                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1022                                 true);
1023                 dump_stack();
1024         }
1025         call_rcu(&inode->i_rcu, ext4_i_callback);
1026 }
1027
1028 static void init_once(void *foo)
1029 {
1030         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1031
1032         INIT_LIST_HEAD(&ei->i_orphan);
1033         init_rwsem(&ei->xattr_sem);
1034         init_rwsem(&ei->i_data_sem);
1035         init_rwsem(&ei->i_mmap_sem);
1036         inode_init_once(&ei->vfs_inode);
1037 }
1038
1039 static int __init init_inodecache(void)
1040 {
1041         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1042                                 sizeof(struct ext4_inode_info), 0,
1043                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1044                                         SLAB_ACCOUNT),
1045                                 offsetof(struct ext4_inode_info, i_data),
1046                                 sizeof_field(struct ext4_inode_info, i_data),
1047                                 init_once);
1048         if (ext4_inode_cachep == NULL)
1049                 return -ENOMEM;
1050         return 0;
1051 }
1052
1053 static void destroy_inodecache(void)
1054 {
1055         /*
1056          * Make sure all delayed rcu free inodes are flushed before we
1057          * destroy cache.
1058          */
1059         rcu_barrier();
1060         kmem_cache_destroy(ext4_inode_cachep);
1061 }
1062
1063 void ext4_clear_inode(struct inode *inode)
1064 {
1065         invalidate_inode_buffers(inode);
1066         clear_inode(inode);
1067         dquot_drop(inode);
1068         ext4_discard_preallocations(inode);
1069         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1070         if (EXT4_I(inode)->jinode) {
1071                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1072                                                EXT4_I(inode)->jinode);
1073                 jbd2_free_inode(EXT4_I(inode)->jinode);
1074                 EXT4_I(inode)->jinode = NULL;
1075         }
1076         fscrypt_put_encryption_info(inode);
1077 }
1078
1079 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1080                                         u64 ino, u32 generation)
1081 {
1082         struct inode *inode;
1083
1084         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1085                 return ERR_PTR(-ESTALE);
1086         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1087                 return ERR_PTR(-ESTALE);
1088
1089         /* iget isn't really right if the inode is currently unallocated!!
1090          *
1091          * ext4_read_inode will return a bad_inode if the inode had been
1092          * deleted, so we should be safe.
1093          *
1094          * Currently we don't know the generation for parent directory, so
1095          * a generation of 0 means "accept any"
1096          */
1097         inode = ext4_iget_normal(sb, ino);
1098         if (IS_ERR(inode))
1099                 return ERR_CAST(inode);
1100         if (generation && inode->i_generation != generation) {
1101                 iput(inode);
1102                 return ERR_PTR(-ESTALE);
1103         }
1104
1105         return inode;
1106 }
1107
1108 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1109                                         int fh_len, int fh_type)
1110 {
1111         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1112                                     ext4_nfs_get_inode);
1113 }
1114
1115 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1116                                         int fh_len, int fh_type)
1117 {
1118         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1119                                     ext4_nfs_get_inode);
1120 }
1121
1122 /*
1123  * Try to release metadata pages (indirect blocks, directories) which are
1124  * mapped via the block device.  Since these pages could have journal heads
1125  * which would prevent try_to_free_buffers() from freeing them, we must use
1126  * jbd2 layer's try_to_free_buffers() function to release them.
1127  */
1128 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1129                                  gfp_t wait)
1130 {
1131         journal_t *journal = EXT4_SB(sb)->s_journal;
1132
1133         WARN_ON(PageChecked(page));
1134         if (!page_has_buffers(page))
1135                 return 0;
1136         if (journal)
1137                 return jbd2_journal_try_to_free_buffers(journal, page,
1138                                                 wait & ~__GFP_DIRECT_RECLAIM);
1139         return try_to_free_buffers(page);
1140 }
1141
1142 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1143 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1144 {
1145         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1146                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1147 }
1148
1149 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1150                                                         void *fs_data)
1151 {
1152         handle_t *handle = fs_data;
1153         int res, res2, credits, retries = 0;
1154
1155         /*
1156          * Encrypting the root directory is not allowed because e2fsck expects
1157          * lost+found to exist and be unencrypted, and encrypting the root
1158          * directory would imply encrypting the lost+found directory as well as
1159          * the filename "lost+found" itself.
1160          */
1161         if (inode->i_ino == EXT4_ROOT_INO)
1162                 return -EPERM;
1163
1164         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1165                 return -EINVAL;
1166
1167         res = ext4_convert_inline_data(inode);
1168         if (res)
1169                 return res;
1170
1171         /*
1172          * If a journal handle was specified, then the encryption context is
1173          * being set on a new inode via inheritance and is part of a larger
1174          * transaction to create the inode.  Otherwise the encryption context is
1175          * being set on an existing inode in its own transaction.  Only in the
1176          * latter case should the "retry on ENOSPC" logic be used.
1177          */
1178
1179         if (handle) {
1180                 res = ext4_xattr_set_handle(handle, inode,
1181                                             EXT4_XATTR_INDEX_ENCRYPTION,
1182                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1183                                             ctx, len, 0);
1184                 if (!res) {
1185                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1186                         ext4_clear_inode_state(inode,
1187                                         EXT4_STATE_MAY_INLINE_DATA);
1188                         /*
1189                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1190                          * S_DAX may be disabled
1191                          */
1192                         ext4_set_inode_flags(inode);
1193                 }
1194                 return res;
1195         }
1196
1197         res = dquot_initialize(inode);
1198         if (res)
1199                 return res;
1200 retry:
1201         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1202                                      &credits);
1203         if (res)
1204                 return res;
1205
1206         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1207         if (IS_ERR(handle))
1208                 return PTR_ERR(handle);
1209
1210         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1211                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1212                                     ctx, len, 0);
1213         if (!res) {
1214                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1215                 /*
1216                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1217                  * S_DAX may be disabled
1218                  */
1219                 ext4_set_inode_flags(inode);
1220                 res = ext4_mark_inode_dirty(handle, inode);
1221                 if (res)
1222                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1223         }
1224         res2 = ext4_journal_stop(handle);
1225
1226         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1227                 goto retry;
1228         if (!res)
1229                 res = res2;
1230         return res;
1231 }
1232
1233 static bool ext4_dummy_context(struct inode *inode)
1234 {
1235         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1236 }
1237
1238 static unsigned ext4_max_namelen(struct inode *inode)
1239 {
1240         return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
1241                 EXT4_NAME_LEN;
1242 }
1243
1244 static const struct fscrypt_operations ext4_cryptops = {
1245         .key_prefix             = "ext4:",
1246         .get_context            = ext4_get_context,
1247         .set_context            = ext4_set_context,
1248         .dummy_context          = ext4_dummy_context,
1249         .empty_dir              = ext4_empty_dir,
1250         .max_namelen            = ext4_max_namelen,
1251 };
1252 #endif
1253
1254 #ifdef CONFIG_QUOTA
1255 static const char * const quotatypes[] = INITQFNAMES;
1256 #define QTYPE2NAME(t) (quotatypes[t])
1257
1258 static int ext4_write_dquot(struct dquot *dquot);
1259 static int ext4_acquire_dquot(struct dquot *dquot);
1260 static int ext4_release_dquot(struct dquot *dquot);
1261 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1262 static int ext4_write_info(struct super_block *sb, int type);
1263 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1264                          const struct path *path);
1265 static int ext4_quota_on_mount(struct super_block *sb, int type);
1266 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1267                                size_t len, loff_t off);
1268 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1269                                 const char *data, size_t len, loff_t off);
1270 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1271                              unsigned int flags);
1272 static int ext4_enable_quotas(struct super_block *sb);
1273 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1274
1275 static struct dquot **ext4_get_dquots(struct inode *inode)
1276 {
1277         return EXT4_I(inode)->i_dquot;
1278 }
1279
1280 static const struct dquot_operations ext4_quota_operations = {
1281         .get_reserved_space     = ext4_get_reserved_space,
1282         .write_dquot            = ext4_write_dquot,
1283         .acquire_dquot          = ext4_acquire_dquot,
1284         .release_dquot          = ext4_release_dquot,
1285         .mark_dirty             = ext4_mark_dquot_dirty,
1286         .write_info             = ext4_write_info,
1287         .alloc_dquot            = dquot_alloc,
1288         .destroy_dquot          = dquot_destroy,
1289         .get_projid             = ext4_get_projid,
1290         .get_inode_usage        = ext4_get_inode_usage,
1291         .get_next_id            = ext4_get_next_id,
1292 };
1293
1294 static const struct quotactl_ops ext4_qctl_operations = {
1295         .quota_on       = ext4_quota_on,
1296         .quota_off      = ext4_quota_off,
1297         .quota_sync     = dquot_quota_sync,
1298         .get_state      = dquot_get_state,
1299         .set_info       = dquot_set_dqinfo,
1300         .get_dqblk      = dquot_get_dqblk,
1301         .set_dqblk      = dquot_set_dqblk,
1302         .get_nextdqblk  = dquot_get_next_dqblk,
1303 };
1304 #endif
1305
1306 static const struct super_operations ext4_sops = {
1307         .alloc_inode    = ext4_alloc_inode,
1308         .destroy_inode  = ext4_destroy_inode,
1309         .write_inode    = ext4_write_inode,
1310         .dirty_inode    = ext4_dirty_inode,
1311         .drop_inode     = ext4_drop_inode,
1312         .evict_inode    = ext4_evict_inode,
1313         .put_super      = ext4_put_super,
1314         .sync_fs        = ext4_sync_fs,
1315         .freeze_fs      = ext4_freeze,
1316         .unfreeze_fs    = ext4_unfreeze,
1317         .statfs         = ext4_statfs,
1318         .remount_fs     = ext4_remount,
1319         .show_options   = ext4_show_options,
1320 #ifdef CONFIG_QUOTA
1321         .quota_read     = ext4_quota_read,
1322         .quota_write    = ext4_quota_write,
1323         .get_dquots     = ext4_get_dquots,
1324 #endif
1325         .bdev_try_to_free_page = bdev_try_to_free_page,
1326 };
1327
1328 static const struct export_operations ext4_export_ops = {
1329         .fh_to_dentry = ext4_fh_to_dentry,
1330         .fh_to_parent = ext4_fh_to_parent,
1331         .get_parent = ext4_get_parent,
1332 };
1333
1334 enum {
1335         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1336         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1337         Opt_nouid32, Opt_debug, Opt_removed,
1338         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1339         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1340         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1341         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1342         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1343         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1344         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1345         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1346         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1347         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1348         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1349         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1350         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1351         Opt_inode_readahead_blks, Opt_journal_ioprio,
1352         Opt_dioread_nolock, Opt_dioread_lock,
1353         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1354         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1355 };
1356
1357 static const match_table_t tokens = {
1358         {Opt_bsd_df, "bsddf"},
1359         {Opt_minix_df, "minixdf"},
1360         {Opt_grpid, "grpid"},
1361         {Opt_grpid, "bsdgroups"},
1362         {Opt_nogrpid, "nogrpid"},
1363         {Opt_nogrpid, "sysvgroups"},
1364         {Opt_resgid, "resgid=%u"},
1365         {Opt_resuid, "resuid=%u"},
1366         {Opt_sb, "sb=%u"},
1367         {Opt_err_cont, "errors=continue"},
1368         {Opt_err_panic, "errors=panic"},
1369         {Opt_err_ro, "errors=remount-ro"},
1370         {Opt_nouid32, "nouid32"},
1371         {Opt_debug, "debug"},
1372         {Opt_removed, "oldalloc"},
1373         {Opt_removed, "orlov"},
1374         {Opt_user_xattr, "user_xattr"},
1375         {Opt_nouser_xattr, "nouser_xattr"},
1376         {Opt_acl, "acl"},
1377         {Opt_noacl, "noacl"},
1378         {Opt_noload, "norecovery"},
1379         {Opt_noload, "noload"},
1380         {Opt_removed, "nobh"},
1381         {Opt_removed, "bh"},
1382         {Opt_commit, "commit=%u"},
1383         {Opt_min_batch_time, "min_batch_time=%u"},
1384         {Opt_max_batch_time, "max_batch_time=%u"},
1385         {Opt_journal_dev, "journal_dev=%u"},
1386         {Opt_journal_path, "journal_path=%s"},
1387         {Opt_journal_checksum, "journal_checksum"},
1388         {Opt_nojournal_checksum, "nojournal_checksum"},
1389         {Opt_journal_async_commit, "journal_async_commit"},
1390         {Opt_abort, "abort"},
1391         {Opt_data_journal, "data=journal"},
1392         {Opt_data_ordered, "data=ordered"},
1393         {Opt_data_writeback, "data=writeback"},
1394         {Opt_data_err_abort, "data_err=abort"},
1395         {Opt_data_err_ignore, "data_err=ignore"},
1396         {Opt_offusrjquota, "usrjquota="},
1397         {Opt_usrjquota, "usrjquota=%s"},
1398         {Opt_offgrpjquota, "grpjquota="},
1399         {Opt_grpjquota, "grpjquota=%s"},
1400         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1401         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1402         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1403         {Opt_grpquota, "grpquota"},
1404         {Opt_noquota, "noquota"},
1405         {Opt_quota, "quota"},
1406         {Opt_usrquota, "usrquota"},
1407         {Opt_prjquota, "prjquota"},
1408         {Opt_barrier, "barrier=%u"},
1409         {Opt_barrier, "barrier"},
1410         {Opt_nobarrier, "nobarrier"},
1411         {Opt_i_version, "i_version"},
1412         {Opt_dax, "dax"},
1413         {Opt_stripe, "stripe=%u"},
1414         {Opt_delalloc, "delalloc"},
1415         {Opt_lazytime, "lazytime"},
1416         {Opt_nolazytime, "nolazytime"},
1417         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1418         {Opt_nodelalloc, "nodelalloc"},
1419         {Opt_removed, "mblk_io_submit"},
1420         {Opt_removed, "nomblk_io_submit"},
1421         {Opt_block_validity, "block_validity"},
1422         {Opt_noblock_validity, "noblock_validity"},
1423         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1424         {Opt_journal_ioprio, "journal_ioprio=%u"},
1425         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1426         {Opt_auto_da_alloc, "auto_da_alloc"},
1427         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1428         {Opt_dioread_nolock, "dioread_nolock"},
1429         {Opt_dioread_lock, "dioread_lock"},
1430         {Opt_discard, "discard"},
1431         {Opt_nodiscard, "nodiscard"},
1432         {Opt_init_itable, "init_itable=%u"},
1433         {Opt_init_itable, "init_itable"},
1434         {Opt_noinit_itable, "noinit_itable"},
1435         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1436         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1437         {Opt_nombcache, "nombcache"},
1438         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1439         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1440         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1441         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1442         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1443         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1444         {Opt_err, NULL},
1445 };
1446
1447 static ext4_fsblk_t get_sb_block(void **data)
1448 {
1449         ext4_fsblk_t    sb_block;
1450         char            *options = (char *) *data;
1451
1452         if (!options || strncmp(options, "sb=", 3) != 0)
1453                 return 1;       /* Default location */
1454
1455         options += 3;
1456         /* TODO: use simple_strtoll with >32bit ext4 */
1457         sb_block = simple_strtoul(options, &options, 0);
1458         if (*options && *options != ',') {
1459                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1460                        (char *) *data);
1461                 return 1;
1462         }
1463         if (*options == ',')
1464                 options++;
1465         *data = (void *) options;
1466
1467         return sb_block;
1468 }
1469
1470 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1471 static const char deprecated_msg[] =
1472         "Mount option \"%s\" will be removed by %s\n"
1473         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1474
1475 #ifdef CONFIG_QUOTA
1476 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1477 {
1478         struct ext4_sb_info *sbi = EXT4_SB(sb);
1479         char *qname;
1480         int ret = -1;
1481
1482         if (sb_any_quota_loaded(sb) &&
1483                 !sbi->s_qf_names[qtype]) {
1484                 ext4_msg(sb, KERN_ERR,
1485                         "Cannot change journaled "
1486                         "quota options when quota turned on");
1487                 return -1;
1488         }
1489         if (ext4_has_feature_quota(sb)) {
1490                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1491                          "ignored when QUOTA feature is enabled");
1492                 return 1;
1493         }
1494         qname = match_strdup(args);
1495         if (!qname) {
1496                 ext4_msg(sb, KERN_ERR,
1497                         "Not enough memory for storing quotafile name");
1498                 return -1;
1499         }
1500         if (sbi->s_qf_names[qtype]) {
1501                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1502                         ret = 1;
1503                 else
1504                         ext4_msg(sb, KERN_ERR,
1505                                  "%s quota file already specified",
1506                                  QTYPE2NAME(qtype));
1507                 goto errout;
1508         }
1509         if (strchr(qname, '/')) {
1510                 ext4_msg(sb, KERN_ERR,
1511                         "quotafile must be on filesystem root");
1512                 goto errout;
1513         }
1514         sbi->s_qf_names[qtype] = qname;
1515         set_opt(sb, QUOTA);
1516         return 1;
1517 errout:
1518         kfree(qname);
1519         return ret;
1520 }
1521
1522 static int clear_qf_name(struct super_block *sb, int qtype)
1523 {
1524
1525         struct ext4_sb_info *sbi = EXT4_SB(sb);
1526
1527         if (sb_any_quota_loaded(sb) &&
1528                 sbi->s_qf_names[qtype]) {
1529                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1530                         " when quota turned on");
1531                 return -1;
1532         }
1533         kfree(sbi->s_qf_names[qtype]);
1534         sbi->s_qf_names[qtype] = NULL;
1535         return 1;
1536 }
1537 #endif
1538
1539 #define MOPT_SET        0x0001
1540 #define MOPT_CLEAR      0x0002
1541 #define MOPT_NOSUPPORT  0x0004
1542 #define MOPT_EXPLICIT   0x0008
1543 #define MOPT_CLEAR_ERR  0x0010
1544 #define MOPT_GTE0       0x0020
1545 #ifdef CONFIG_QUOTA
1546 #define MOPT_Q          0
1547 #define MOPT_QFMT       0x0040
1548 #else
1549 #define MOPT_Q          MOPT_NOSUPPORT
1550 #define MOPT_QFMT       MOPT_NOSUPPORT
1551 #endif
1552 #define MOPT_DATAJ      0x0080
1553 #define MOPT_NO_EXT2    0x0100
1554 #define MOPT_NO_EXT3    0x0200
1555 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1556 #define MOPT_STRING     0x0400
1557
1558 static const struct mount_opts {
1559         int     token;
1560         int     mount_opt;
1561         int     flags;
1562 } ext4_mount_opts[] = {
1563         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1564         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1565         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1566         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1567         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1568         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1569         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1570          MOPT_EXT4_ONLY | MOPT_SET},
1571         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1572          MOPT_EXT4_ONLY | MOPT_CLEAR},
1573         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1574         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1575         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1576          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1577         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1578          MOPT_EXT4_ONLY | MOPT_CLEAR},
1579         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1580          MOPT_EXT4_ONLY | MOPT_CLEAR},
1581         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1582          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1583         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1584                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1585          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1586         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1587         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1588         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1589         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1590         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1591          MOPT_NO_EXT2},
1592         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1593          MOPT_NO_EXT2},
1594         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1595         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1596         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1597         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1598         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1599         {Opt_commit, 0, MOPT_GTE0},
1600         {Opt_max_batch_time, 0, MOPT_GTE0},
1601         {Opt_min_batch_time, 0, MOPT_GTE0},
1602         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1603         {Opt_init_itable, 0, MOPT_GTE0},
1604         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1605         {Opt_stripe, 0, MOPT_GTE0},
1606         {Opt_resuid, 0, MOPT_GTE0},
1607         {Opt_resgid, 0, MOPT_GTE0},
1608         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1609         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1610         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1611         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1612         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1613         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1614          MOPT_NO_EXT2 | MOPT_DATAJ},
1615         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1616         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1617 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1618         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1619         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1620 #else
1621         {Opt_acl, 0, MOPT_NOSUPPORT},
1622         {Opt_noacl, 0, MOPT_NOSUPPORT},
1623 #endif
1624         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1625         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1626         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1627         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1628         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1629                                                         MOPT_SET | MOPT_Q},
1630         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1631                                                         MOPT_SET | MOPT_Q},
1632         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1633                                                         MOPT_SET | MOPT_Q},
1634         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1635                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1636                                                         MOPT_CLEAR | MOPT_Q},
1637         {Opt_usrjquota, 0, MOPT_Q},
1638         {Opt_grpjquota, 0, MOPT_Q},
1639         {Opt_offusrjquota, 0, MOPT_Q},
1640         {Opt_offgrpjquota, 0, MOPT_Q},
1641         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1642         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1643         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1644         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1645         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1646         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1647         {Opt_err, 0, 0}
1648 };
1649
1650 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1651                             substring_t *args, unsigned long *journal_devnum,
1652                             unsigned int *journal_ioprio, int is_remount)
1653 {
1654         struct ext4_sb_info *sbi = EXT4_SB(sb);
1655         const struct mount_opts *m;
1656         kuid_t uid;
1657         kgid_t gid;
1658         int arg = 0;
1659
1660 #ifdef CONFIG_QUOTA
1661         if (token == Opt_usrjquota)
1662                 return set_qf_name(sb, USRQUOTA, &args[0]);
1663         else if (token == Opt_grpjquota)
1664                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1665         else if (token == Opt_offusrjquota)
1666                 return clear_qf_name(sb, USRQUOTA);
1667         else if (token == Opt_offgrpjquota)
1668                 return clear_qf_name(sb, GRPQUOTA);
1669 #endif
1670         switch (token) {
1671         case Opt_noacl:
1672         case Opt_nouser_xattr:
1673                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1674                 break;
1675         case Opt_sb:
1676                 return 1;       /* handled by get_sb_block() */
1677         case Opt_removed:
1678                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1679                 return 1;
1680         case Opt_abort:
1681                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1682                 return 1;
1683         case Opt_i_version:
1684                 sb->s_flags |= SB_I_VERSION;
1685                 return 1;
1686         case Opt_lazytime:
1687                 sb->s_flags |= SB_LAZYTIME;
1688                 return 1;
1689         case Opt_nolazytime:
1690                 sb->s_flags &= ~SB_LAZYTIME;
1691                 return 1;
1692         }
1693
1694         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1695                 if (token == m->token)
1696                         break;
1697
1698         if (m->token == Opt_err) {
1699                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1700                          "or missing value", opt);
1701                 return -1;
1702         }
1703
1704         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1705                 ext4_msg(sb, KERN_ERR,
1706                          "Mount option \"%s\" incompatible with ext2", opt);
1707                 return -1;
1708         }
1709         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1710                 ext4_msg(sb, KERN_ERR,
1711                          "Mount option \"%s\" incompatible with ext3", opt);
1712                 return -1;
1713         }
1714
1715         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1716                 return -1;
1717         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1718                 return -1;
1719         if (m->flags & MOPT_EXPLICIT) {
1720                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1721                         set_opt2(sb, EXPLICIT_DELALLOC);
1722                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1723                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1724                 } else
1725                         return -1;
1726         }
1727         if (m->flags & MOPT_CLEAR_ERR)
1728                 clear_opt(sb, ERRORS_MASK);
1729         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1730                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1731                          "options when quota turned on");
1732                 return -1;
1733         }
1734
1735         if (m->flags & MOPT_NOSUPPORT) {
1736                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1737         } else if (token == Opt_commit) {
1738                 if (arg == 0)
1739                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1740                 sbi->s_commit_interval = HZ * arg;
1741         } else if (token == Opt_debug_want_extra_isize) {
1742                 sbi->s_want_extra_isize = arg;
1743         } else if (token == Opt_max_batch_time) {
1744                 sbi->s_max_batch_time = arg;
1745         } else if (token == Opt_min_batch_time) {
1746                 sbi->s_min_batch_time = arg;
1747         } else if (token == Opt_inode_readahead_blks) {
1748                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1749                         ext4_msg(sb, KERN_ERR,
1750                                  "EXT4-fs: inode_readahead_blks must be "
1751                                  "0 or a power of 2 smaller than 2^31");
1752                         return -1;
1753                 }
1754                 sbi->s_inode_readahead_blks = arg;
1755         } else if (token == Opt_init_itable) {
1756                 set_opt(sb, INIT_INODE_TABLE);
1757                 if (!args->from)
1758                         arg = EXT4_DEF_LI_WAIT_MULT;
1759                 sbi->s_li_wait_mult = arg;
1760         } else if (token == Opt_max_dir_size_kb) {
1761                 sbi->s_max_dir_size_kb = arg;
1762         } else if (token == Opt_stripe) {
1763                 sbi->s_stripe = arg;
1764         } else if (token == Opt_resuid) {
1765                 uid = make_kuid(current_user_ns(), arg);
1766                 if (!uid_valid(uid)) {
1767                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1768                         return -1;
1769                 }
1770                 sbi->s_resuid = uid;
1771         } else if (token == Opt_resgid) {
1772                 gid = make_kgid(current_user_ns(), arg);
1773                 if (!gid_valid(gid)) {
1774                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1775                         return -1;
1776                 }
1777                 sbi->s_resgid = gid;
1778         } else if (token == Opt_journal_dev) {
1779                 if (is_remount) {
1780                         ext4_msg(sb, KERN_ERR,
1781                                  "Cannot specify journal on remount");
1782                         return -1;
1783                 }
1784                 *journal_devnum = arg;
1785         } else if (token == Opt_journal_path) {
1786                 char *journal_path;
1787                 struct inode *journal_inode;
1788                 struct path path;
1789                 int error;
1790
1791                 if (is_remount) {
1792                         ext4_msg(sb, KERN_ERR,
1793                                  "Cannot specify journal on remount");
1794                         return -1;
1795                 }
1796                 journal_path = match_strdup(&args[0]);
1797                 if (!journal_path) {
1798                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1799                                 "journal device string");
1800                         return -1;
1801                 }
1802
1803                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1804                 if (error) {
1805                         ext4_msg(sb, KERN_ERR, "error: could not find "
1806                                 "journal device path: error %d", error);
1807                         kfree(journal_path);
1808                         return -1;
1809                 }
1810
1811                 journal_inode = d_inode(path.dentry);
1812                 if (!S_ISBLK(journal_inode->i_mode)) {
1813                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1814                                 "is not a block device", journal_path);
1815                         path_put(&path);
1816                         kfree(journal_path);
1817                         return -1;
1818                 }
1819
1820                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1821                 path_put(&path);
1822                 kfree(journal_path);
1823         } else if (token == Opt_journal_ioprio) {
1824                 if (arg > 7) {
1825                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1826                                  " (must be 0-7)");
1827                         return -1;
1828                 }
1829                 *journal_ioprio =
1830                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1831         } else if (token == Opt_test_dummy_encryption) {
1832 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1833                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1834                 ext4_msg(sb, KERN_WARNING,
1835                          "Test dummy encryption mode enabled");
1836 #else
1837                 ext4_msg(sb, KERN_WARNING,
1838                          "Test dummy encryption mount option ignored");
1839 #endif
1840         } else if (m->flags & MOPT_DATAJ) {
1841                 if (is_remount) {
1842                         if (!sbi->s_journal)
1843                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1844                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1845                                 ext4_msg(sb, KERN_ERR,
1846                                          "Cannot change data mode on remount");
1847                                 return -1;
1848                         }
1849                 } else {
1850                         clear_opt(sb, DATA_FLAGS);
1851                         sbi->s_mount_opt |= m->mount_opt;
1852                 }
1853 #ifdef CONFIG_QUOTA
1854         } else if (m->flags & MOPT_QFMT) {
1855                 if (sb_any_quota_loaded(sb) &&
1856                     sbi->s_jquota_fmt != m->mount_opt) {
1857                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1858                                  "quota options when quota turned on");
1859                         return -1;
1860                 }
1861                 if (ext4_has_feature_quota(sb)) {
1862                         ext4_msg(sb, KERN_INFO,
1863                                  "Quota format mount options ignored "
1864                                  "when QUOTA feature is enabled");
1865                         return 1;
1866                 }
1867                 sbi->s_jquota_fmt = m->mount_opt;
1868 #endif
1869         } else if (token == Opt_dax) {
1870 #ifdef CONFIG_FS_DAX
1871                 ext4_msg(sb, KERN_WARNING,
1872                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1873                         sbi->s_mount_opt |= m->mount_opt;
1874 #else
1875                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1876                 return -1;
1877 #endif
1878         } else if (token == Opt_data_err_abort) {
1879                 sbi->s_mount_opt |= m->mount_opt;
1880         } else if (token == Opt_data_err_ignore) {
1881                 sbi->s_mount_opt &= ~m->mount_opt;
1882         } else {
1883                 if (!args->from)
1884                         arg = 1;
1885                 if (m->flags & MOPT_CLEAR)
1886                         arg = !arg;
1887                 else if (unlikely(!(m->flags & MOPT_SET))) {
1888                         ext4_msg(sb, KERN_WARNING,
1889                                  "buggy handling of option %s", opt);
1890                         WARN_ON(1);
1891                         return -1;
1892                 }
1893                 if (arg != 0)
1894                         sbi->s_mount_opt |= m->mount_opt;
1895                 else
1896                         sbi->s_mount_opt &= ~m->mount_opt;
1897         }
1898         return 1;
1899 }
1900
1901 static int parse_options(char *options, struct super_block *sb,
1902                          unsigned long *journal_devnum,
1903                          unsigned int *journal_ioprio,
1904                          int is_remount)
1905 {
1906         struct ext4_sb_info *sbi = EXT4_SB(sb);
1907         char *p;
1908         substring_t args[MAX_OPT_ARGS];
1909         int token;
1910
1911         if (!options)
1912                 return 1;
1913
1914         while ((p = strsep(&options, ",")) != NULL) {
1915                 if (!*p)
1916                         continue;
1917                 /*
1918                  * Initialize args struct so we know whether arg was
1919                  * found; some options take optional arguments.
1920                  */
1921                 args[0].to = args[0].from = NULL;
1922                 token = match_token(p, tokens, args);
1923                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1924                                      journal_ioprio, is_remount) < 0)
1925                         return 0;
1926         }
1927 #ifdef CONFIG_QUOTA
1928         /*
1929          * We do the test below only for project quotas. 'usrquota' and
1930          * 'grpquota' mount options are allowed even without quota feature
1931          * to support legacy quotas in quota files.
1932          */
1933         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
1934                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
1935                          "Cannot enable project quota enforcement.");
1936                 return 0;
1937         }
1938         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1939                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1940                         clear_opt(sb, USRQUOTA);
1941
1942                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1943                         clear_opt(sb, GRPQUOTA);
1944
1945                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1946                         ext4_msg(sb, KERN_ERR, "old and new quota "
1947                                         "format mixing");
1948                         return 0;
1949                 }
1950
1951                 if (!sbi->s_jquota_fmt) {
1952                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1953                                         "not specified");
1954                         return 0;
1955                 }
1956         }
1957 #endif
1958         if (test_opt(sb, DIOREAD_NOLOCK)) {
1959                 int blocksize =
1960                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1961
1962                 if (blocksize < PAGE_SIZE) {
1963                         ext4_msg(sb, KERN_ERR, "can't mount with "
1964                                  "dioread_nolock if block size != PAGE_SIZE");
1965                         return 0;
1966                 }
1967         }
1968         return 1;
1969 }
1970
1971 static inline void ext4_show_quota_options(struct seq_file *seq,
1972                                            struct super_block *sb)
1973 {
1974 #if defined(CONFIG_QUOTA)
1975         struct ext4_sb_info *sbi = EXT4_SB(sb);
1976
1977         if (sbi->s_jquota_fmt) {
1978                 char *fmtname = "";
1979
1980                 switch (sbi->s_jquota_fmt) {
1981                 case QFMT_VFS_OLD:
1982                         fmtname = "vfsold";
1983                         break;
1984                 case QFMT_VFS_V0:
1985                         fmtname = "vfsv0";
1986                         break;
1987                 case QFMT_VFS_V1:
1988                         fmtname = "vfsv1";
1989                         break;
1990                 }
1991                 seq_printf(seq, ",jqfmt=%s", fmtname);
1992         }
1993
1994         if (sbi->s_qf_names[USRQUOTA])
1995                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1996
1997         if (sbi->s_qf_names[GRPQUOTA])
1998                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1999 #endif
2000 }
2001
2002 static const char *token2str(int token)
2003 {
2004         const struct match_token *t;
2005
2006         for (t = tokens; t->token != Opt_err; t++)
2007                 if (t->token == token && !strchr(t->pattern, '='))
2008                         break;
2009         return t->pattern;
2010 }
2011
2012 /*
2013  * Show an option if
2014  *  - it's set to a non-default value OR
2015  *  - if the per-sb default is different from the global default
2016  */
2017 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2018                               int nodefs)
2019 {
2020         struct ext4_sb_info *sbi = EXT4_SB(sb);
2021         struct ext4_super_block *es = sbi->s_es;
2022         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
2023         const struct mount_opts *m;
2024         char sep = nodefs ? '\n' : ',';
2025
2026 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2027 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2028
2029         if (sbi->s_sb_block != 1)
2030                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2031
2032         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2033                 int want_set = m->flags & MOPT_SET;
2034                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2035                     (m->flags & MOPT_CLEAR_ERR))
2036                         continue;
2037                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2038                         continue; /* skip if same as the default */
2039                 if ((want_set &&
2040                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2041                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2042                         continue; /* select Opt_noFoo vs Opt_Foo */
2043                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2044         }
2045
2046         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2047             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2048                 SEQ_OPTS_PRINT("resuid=%u",
2049                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2050         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2051             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2052                 SEQ_OPTS_PRINT("resgid=%u",
2053                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2054         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2055         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2056                 SEQ_OPTS_PUTS("errors=remount-ro");
2057         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2058                 SEQ_OPTS_PUTS("errors=continue");
2059         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2060                 SEQ_OPTS_PUTS("errors=panic");
2061         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2062                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2063         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2064                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2065         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2066                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2067         if (sb->s_flags & SB_I_VERSION)
2068                 SEQ_OPTS_PUTS("i_version");
2069         if (nodefs || sbi->s_stripe)
2070                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2071         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
2072                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2073                         SEQ_OPTS_PUTS("data=journal");
2074                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2075                         SEQ_OPTS_PUTS("data=ordered");
2076                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2077                         SEQ_OPTS_PUTS("data=writeback");
2078         }
2079         if (nodefs ||
2080             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2081                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2082                                sbi->s_inode_readahead_blks);
2083
2084         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
2085                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2086                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2087         if (nodefs || sbi->s_max_dir_size_kb)
2088                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2089         if (test_opt(sb, DATA_ERR_ABORT))
2090                 SEQ_OPTS_PUTS("data_err=abort");
2091
2092         ext4_show_quota_options(seq, sb);
2093         return 0;
2094 }
2095
2096 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2097 {
2098         return _ext4_show_options(seq, root->d_sb, 0);
2099 }
2100
2101 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2102 {
2103         struct super_block *sb = seq->private;
2104         int rc;
2105
2106         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2107         rc = _ext4_show_options(seq, sb, 1);
2108         seq_puts(seq, "\n");
2109         return rc;
2110 }
2111
2112 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2113                             int read_only)
2114 {
2115         struct ext4_sb_info *sbi = EXT4_SB(sb);
2116         int res = 0;
2117
2118         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2119                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2120                          "forcing read-only mode");
2121                 res = SB_RDONLY;
2122         }
2123         if (read_only)
2124                 goto done;
2125         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2126                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2127                          "running e2fsck is recommended");
2128         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2129                 ext4_msg(sb, KERN_WARNING,
2130                          "warning: mounting fs with errors, "
2131                          "running e2fsck is recommended");
2132         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2133                  le16_to_cpu(es->s_mnt_count) >=
2134                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2135                 ext4_msg(sb, KERN_WARNING,
2136                          "warning: maximal mount count reached, "
2137                          "running e2fsck is recommended");
2138         else if (le32_to_cpu(es->s_checkinterval) &&
2139                 (le32_to_cpu(es->s_lastcheck) +
2140                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
2141                 ext4_msg(sb, KERN_WARNING,
2142                          "warning: checktime reached, "
2143                          "running e2fsck is recommended");
2144         if (!sbi->s_journal)
2145                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2146         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2147                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2148         le16_add_cpu(&es->s_mnt_count, 1);
2149         es->s_mtime = cpu_to_le32(get_seconds());
2150         ext4_update_dynamic_rev(sb);
2151         if (sbi->s_journal)
2152                 ext4_set_feature_journal_needs_recovery(sb);
2153
2154         ext4_commit_super(sb, 1);
2155 done:
2156         if (test_opt(sb, DEBUG))
2157                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2158                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2159                         sb->s_blocksize,
2160                         sbi->s_groups_count,
2161                         EXT4_BLOCKS_PER_GROUP(sb),
2162                         EXT4_INODES_PER_GROUP(sb),
2163                         sbi->s_mount_opt, sbi->s_mount_opt2);
2164
2165         cleancache_init_fs(sb);
2166         return res;
2167 }
2168
2169 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2170 {
2171         struct ext4_sb_info *sbi = EXT4_SB(sb);
2172         struct flex_groups *new_groups;
2173         int size;
2174
2175         if (!sbi->s_log_groups_per_flex)
2176                 return 0;
2177
2178         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2179         if (size <= sbi->s_flex_groups_allocated)
2180                 return 0;
2181
2182         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2183         new_groups = kvzalloc(size, GFP_KERNEL);
2184         if (!new_groups) {
2185                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2186                          size / (int) sizeof(struct flex_groups));
2187                 return -ENOMEM;
2188         }
2189
2190         if (sbi->s_flex_groups) {
2191                 memcpy(new_groups, sbi->s_flex_groups,
2192                        (sbi->s_flex_groups_allocated *
2193                         sizeof(struct flex_groups)));
2194                 kvfree(sbi->s_flex_groups);
2195         }
2196         sbi->s_flex_groups = new_groups;
2197         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2198         return 0;
2199 }
2200
2201 static int ext4_fill_flex_info(struct super_block *sb)
2202 {
2203         struct ext4_sb_info *sbi = EXT4_SB(sb);
2204         struct ext4_group_desc *gdp = NULL;
2205         ext4_group_t flex_group;
2206         int i, err;
2207
2208         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2209         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2210                 sbi->s_log_groups_per_flex = 0;
2211                 return 1;
2212         }
2213
2214         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2215         if (err)
2216                 goto failed;
2217
2218         for (i = 0; i < sbi->s_groups_count; i++) {
2219                 gdp = ext4_get_group_desc(sb, i, NULL);
2220
2221                 flex_group = ext4_flex_group(sbi, i);
2222                 atomic_add(ext4_free_inodes_count(sb, gdp),
2223                            &sbi->s_flex_groups[flex_group].free_inodes);
2224                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2225                              &sbi->s_flex_groups[flex_group].free_clusters);
2226                 atomic_add(ext4_used_dirs_count(sb, gdp),
2227                            &sbi->s_flex_groups[flex_group].used_dirs);
2228         }
2229
2230         return 1;
2231 failed:
2232         return 0;
2233 }
2234
2235 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2236                                    struct ext4_group_desc *gdp)
2237 {
2238         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2239         __u16 crc = 0;
2240         __le32 le_group = cpu_to_le32(block_group);
2241         struct ext4_sb_info *sbi = EXT4_SB(sb);
2242
2243         if (ext4_has_metadata_csum(sbi->s_sb)) {
2244                 /* Use new metadata_csum algorithm */
2245                 __u32 csum32;
2246                 __u16 dummy_csum = 0;
2247
2248                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2249                                      sizeof(le_group));
2250                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2251                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2252                                      sizeof(dummy_csum));
2253                 offset += sizeof(dummy_csum);
2254                 if (offset < sbi->s_desc_size)
2255                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2256                                              sbi->s_desc_size - offset);
2257
2258                 crc = csum32 & 0xFFFF;
2259                 goto out;
2260         }
2261
2262         /* old crc16 code */
2263         if (!ext4_has_feature_gdt_csum(sb))
2264                 return 0;
2265
2266         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2267         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2268         crc = crc16(crc, (__u8 *)gdp, offset);
2269         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2270         /* for checksum of struct ext4_group_desc do the rest...*/
2271         if (ext4_has_feature_64bit(sb) &&
2272             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2273                 crc = crc16(crc, (__u8 *)gdp + offset,
2274                             le16_to_cpu(sbi->s_es->s_desc_size) -
2275                                 offset);
2276
2277 out:
2278         return cpu_to_le16(crc);
2279 }
2280
2281 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2282                                 struct ext4_group_desc *gdp)
2283 {
2284         if (ext4_has_group_desc_csum(sb) &&
2285             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2286                 return 0;
2287
2288         return 1;
2289 }
2290
2291 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2292                               struct ext4_group_desc *gdp)
2293 {
2294         if (!ext4_has_group_desc_csum(sb))
2295                 return;
2296         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2297 }
2298
2299 /* Called at mount-time, super-block is locked */
2300 static int ext4_check_descriptors(struct super_block *sb,
2301                                   ext4_fsblk_t sb_block,
2302                                   ext4_group_t *first_not_zeroed)
2303 {
2304         struct ext4_sb_info *sbi = EXT4_SB(sb);
2305         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2306         ext4_fsblk_t last_block;
2307         ext4_fsblk_t block_bitmap;
2308         ext4_fsblk_t inode_bitmap;
2309         ext4_fsblk_t inode_table;
2310         int flexbg_flag = 0;
2311         ext4_group_t i, grp = sbi->s_groups_count;
2312
2313         if (ext4_has_feature_flex_bg(sb))
2314                 flexbg_flag = 1;
2315
2316         ext4_debug("Checking group descriptors");
2317
2318         for (i = 0; i < sbi->s_groups_count; i++) {
2319                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2320
2321                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2322                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2323                 else
2324                         last_block = first_block +
2325                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2326
2327                 if ((grp == sbi->s_groups_count) &&
2328                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2329                         grp = i;
2330
2331                 block_bitmap = ext4_block_bitmap(sb, gdp);
2332                 if (block_bitmap == sb_block) {
2333                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2334                                  "Block bitmap for group %u overlaps "
2335                                  "superblock", i);
2336                 }
2337                 if (block_bitmap < first_block || block_bitmap > last_block) {
2338                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2339                                "Block bitmap for group %u not in group "
2340                                "(block %llu)!", i, block_bitmap);
2341                         return 0;
2342                 }
2343                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2344                 if (inode_bitmap == sb_block) {
2345                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2346                                  "Inode bitmap for group %u overlaps "
2347                                  "superblock", i);
2348                 }
2349                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2350                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2351                                "Inode bitmap for group %u not in group "
2352                                "(block %llu)!", i, inode_bitmap);
2353                         return 0;
2354                 }
2355                 inode_table = ext4_inode_table(sb, gdp);
2356                 if (inode_table == sb_block) {
2357                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2358                                  "Inode table for group %u overlaps "
2359                                  "superblock", i);
2360                 }
2361                 if (inode_table < first_block ||
2362                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2363                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2364                                "Inode table for group %u not in group "
2365                                "(block %llu)!", i, inode_table);
2366                         return 0;
2367                 }
2368                 ext4_lock_group(sb, i);
2369                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2370                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2371                                  "Checksum for group %u failed (%u!=%u)",
2372                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2373                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2374                         if (!sb_rdonly(sb)) {
2375                                 ext4_unlock_group(sb, i);
2376                                 return 0;
2377                         }
2378                 }
2379                 ext4_unlock_group(sb, i);
2380                 if (!flexbg_flag)
2381                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2382         }
2383         if (NULL != first_not_zeroed)
2384                 *first_not_zeroed = grp;
2385         return 1;
2386 }
2387
2388 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2389  * the superblock) which were deleted from all directories, but held open by
2390  * a process at the time of a crash.  We walk the list and try to delete these
2391  * inodes at recovery time (only with a read-write filesystem).
2392  *
2393  * In order to keep the orphan inode chain consistent during traversal (in
2394  * case of crash during recovery), we link each inode into the superblock
2395  * orphan list_head and handle it the same way as an inode deletion during
2396  * normal operation (which journals the operations for us).
2397  *
2398  * We only do an iget() and an iput() on each inode, which is very safe if we
2399  * accidentally point at an in-use or already deleted inode.  The worst that
2400  * can happen in this case is that we get a "bit already cleared" message from
2401  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2402  * e2fsck was run on this filesystem, and it must have already done the orphan
2403  * inode cleanup for us, so we can safely abort without any further action.
2404  */
2405 static void ext4_orphan_cleanup(struct super_block *sb,
2406                                 struct ext4_super_block *es)
2407 {
2408         unsigned int s_flags = sb->s_flags;
2409         int ret, nr_orphans = 0, nr_truncates = 0;
2410 #ifdef CONFIG_QUOTA
2411         int quota_update = 0;
2412         int i;
2413 #endif
2414         if (!es->s_last_orphan) {
2415                 jbd_debug(4, "no orphan inodes to clean up\n");
2416                 return;
2417         }
2418
2419         if (bdev_read_only(sb->s_bdev)) {
2420                 ext4_msg(sb, KERN_ERR, "write access "
2421                         "unavailable, skipping orphan cleanup");
2422                 return;
2423         }
2424
2425         /* Check if feature set would not allow a r/w mount */
2426         if (!ext4_feature_set_ok(sb, 0)) {
2427                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2428                          "unknown ROCOMPAT features");
2429                 return;
2430         }
2431
2432         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2433                 /* don't clear list on RO mount w/ errors */
2434                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2435                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2436                                   "clearing orphan list.\n");
2437                         es->s_last_orphan = 0;
2438                 }
2439                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2440                 return;
2441         }
2442
2443         if (s_flags & SB_RDONLY) {
2444                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2445                 sb->s_flags &= ~SB_RDONLY;
2446         }
2447 #ifdef CONFIG_QUOTA
2448         /* Needed for iput() to work correctly and not trash data */
2449         sb->s_flags |= SB_ACTIVE;
2450
2451         /*
2452          * Turn on quotas which were not enabled for read-only mounts if
2453          * filesystem has quota feature, so that they are updated correctly.
2454          */
2455         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2456                 int ret = ext4_enable_quotas(sb);
2457
2458                 if (!ret)
2459                         quota_update = 1;
2460                 else
2461                         ext4_msg(sb, KERN_ERR,
2462                                 "Cannot turn on quotas: error %d", ret);
2463         }
2464
2465         /* Turn on journaled quotas used for old sytle */
2466         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2467                 if (EXT4_SB(sb)->s_qf_names[i]) {
2468                         int ret = ext4_quota_on_mount(sb, i);
2469
2470                         if (!ret)
2471                                 quota_update = 1;
2472                         else
2473                                 ext4_msg(sb, KERN_ERR,
2474                                         "Cannot turn on journaled "
2475                                         "quota: type %d: error %d", i, ret);
2476                 }
2477         }
2478 #endif
2479
2480         while (es->s_last_orphan) {
2481                 struct inode *inode;
2482
2483                 /*
2484                  * We may have encountered an error during cleanup; if
2485                  * so, skip the rest.
2486                  */
2487                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2488                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2489                         es->s_last_orphan = 0;
2490                         break;
2491                 }
2492
2493                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2494                 if (IS_ERR(inode)) {
2495                         es->s_last_orphan = 0;
2496                         break;
2497                 }
2498
2499                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2500                 dquot_initialize(inode);
2501                 if (inode->i_nlink) {
2502                         if (test_opt(sb, DEBUG))
2503                                 ext4_msg(sb, KERN_DEBUG,
2504                                         "%s: truncating inode %lu to %lld bytes",
2505                                         __func__, inode->i_ino, inode->i_size);
2506                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2507                                   inode->i_ino, inode->i_size);
2508                         inode_lock(inode);
2509                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2510                         ret = ext4_truncate(inode);
2511                         if (ret)
2512                                 ext4_std_error(inode->i_sb, ret);
2513                         inode_unlock(inode);
2514                         nr_truncates++;
2515                 } else {
2516                         if (test_opt(sb, DEBUG))
2517                                 ext4_msg(sb, KERN_DEBUG,
2518                                         "%s: deleting unreferenced inode %lu",
2519                                         __func__, inode->i_ino);
2520                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2521                                   inode->i_ino);
2522                         nr_orphans++;
2523                 }
2524                 iput(inode);  /* The delete magic happens here! */
2525         }
2526
2527 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2528
2529         if (nr_orphans)
2530                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2531                        PLURAL(nr_orphans));
2532         if (nr_truncates)
2533                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2534                        PLURAL(nr_truncates));
2535 #ifdef CONFIG_QUOTA
2536         /* Turn off quotas if they were enabled for orphan cleanup */
2537         if (quota_update) {
2538                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2539                         if (sb_dqopt(sb)->files[i])
2540                                 dquot_quota_off(sb, i);
2541                 }
2542         }
2543 #endif
2544         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2545 }
2546
2547 /*
2548  * Maximal extent format file size.
2549  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2550  * extent format containers, within a sector_t, and within i_blocks
2551  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2552  * so that won't be a limiting factor.
2553  *
2554  * However there is other limiting factor. We do store extents in the form
2555  * of starting block and length, hence the resulting length of the extent
2556  * covering maximum file size must fit into on-disk format containers as
2557  * well. Given that length is always by 1 unit bigger than max unit (because
2558  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2559  *
2560  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2561  */
2562 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2563 {
2564         loff_t res;
2565         loff_t upper_limit = MAX_LFS_FILESIZE;
2566
2567         /* small i_blocks in vfs inode? */
2568         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2569                 /*
2570                  * CONFIG_LBDAF is not enabled implies the inode
2571                  * i_block represent total blocks in 512 bytes
2572                  * 32 == size of vfs inode i_blocks * 8
2573                  */
2574                 upper_limit = (1LL << 32) - 1;
2575
2576                 /* total blocks in file system block size */
2577                 upper_limit >>= (blkbits - 9);
2578                 upper_limit <<= blkbits;
2579         }
2580
2581         /*
2582          * 32-bit extent-start container, ee_block. We lower the maxbytes
2583          * by one fs block, so ee_len can cover the extent of maximum file
2584          * size
2585          */
2586         res = (1LL << 32) - 1;
2587         res <<= blkbits;
2588
2589         /* Sanity check against vm- & vfs- imposed limits */
2590         if (res > upper_limit)
2591                 res = upper_limit;
2592
2593         return res;
2594 }
2595
2596 /*
2597  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2598  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2599  * We need to be 1 filesystem block less than the 2^48 sector limit.
2600  */
2601 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2602 {
2603         loff_t res = EXT4_NDIR_BLOCKS;
2604         int meta_blocks;
2605         loff_t upper_limit;
2606         /* This is calculated to be the largest file size for a dense, block
2607          * mapped file such that the file's total number of 512-byte sectors,
2608          * including data and all indirect blocks, does not exceed (2^48 - 1).
2609          *
2610          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2611          * number of 512-byte sectors of the file.
2612          */
2613
2614         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2615                 /*
2616                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2617                  * the inode i_block field represents total file blocks in
2618                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2619                  */
2620                 upper_limit = (1LL << 32) - 1;
2621
2622                 /* total blocks in file system block size */
2623                 upper_limit >>= (bits - 9);
2624
2625         } else {
2626                 /*
2627                  * We use 48 bit ext4_inode i_blocks
2628                  * With EXT4_HUGE_FILE_FL set the i_blocks
2629                  * represent total number of blocks in
2630                  * file system block size
2631                  */
2632                 upper_limit = (1LL << 48) - 1;
2633
2634         }
2635
2636         /* indirect blocks */
2637         meta_blocks = 1;
2638         /* double indirect blocks */
2639         meta_blocks += 1 + (1LL << (bits-2));
2640         /* tripple indirect blocks */
2641         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2642
2643         upper_limit -= meta_blocks;
2644         upper_limit <<= bits;
2645
2646         res += 1LL << (bits-2);
2647         res += 1LL << (2*(bits-2));
2648         res += 1LL << (3*(bits-2));
2649         res <<= bits;
2650         if (res > upper_limit)
2651                 res = upper_limit;
2652
2653         if (res > MAX_LFS_FILESIZE)
2654                 res = MAX_LFS_FILESIZE;
2655
2656         return res;
2657 }
2658
2659 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2660                                    ext4_fsblk_t logical_sb_block, int nr)
2661 {
2662         struct ext4_sb_info *sbi = EXT4_SB(sb);
2663         ext4_group_t bg, first_meta_bg;
2664         int has_super = 0;
2665
2666         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2667
2668         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2669                 return logical_sb_block + nr + 1;
2670         bg = sbi->s_desc_per_block * nr;
2671         if (ext4_bg_has_super(sb, bg))
2672                 has_super = 1;
2673
2674         /*
2675          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2676          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2677          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2678          * compensate.
2679          */
2680         if (sb->s_blocksize == 1024 && nr == 0 &&
2681             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2682                 has_super++;
2683
2684         return (has_super + ext4_group_first_block_no(sb, bg));
2685 }
2686
2687 /**
2688  * ext4_get_stripe_size: Get the stripe size.
2689  * @sbi: In memory super block info
2690  *
2691  * If we have specified it via mount option, then
2692  * use the mount option value. If the value specified at mount time is
2693  * greater than the blocks per group use the super block value.
2694  * If the super block value is greater than blocks per group return 0.
2695  * Allocator needs it be less than blocks per group.
2696  *
2697  */
2698 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2699 {
2700         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2701         unsigned long stripe_width =
2702                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2703         int ret;
2704
2705         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2706                 ret = sbi->s_stripe;
2707         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2708                 ret = stripe_width;
2709         else if (stride && stride <= sbi->s_blocks_per_group)
2710                 ret = stride;
2711         else
2712                 ret = 0;
2713
2714         /*
2715          * If the stripe width is 1, this makes no sense and
2716          * we set it to 0 to turn off stripe handling code.
2717          */
2718         if (ret <= 1)
2719                 ret = 0;
2720
2721         return ret;
2722 }
2723
2724 /*
2725  * Check whether this filesystem can be mounted based on
2726  * the features present and the RDONLY/RDWR mount requested.
2727  * Returns 1 if this filesystem can be mounted as requested,
2728  * 0 if it cannot be.
2729  */
2730 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2731 {
2732         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2733                 ext4_msg(sb, KERN_ERR,
2734                         "Couldn't mount because of "
2735                         "unsupported optional features (%x)",
2736                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2737                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2738                 return 0;
2739         }
2740
2741         if (readonly)
2742                 return 1;
2743
2744         if (ext4_has_feature_readonly(sb)) {
2745                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2746                 sb->s_flags |= SB_RDONLY;
2747                 return 1;
2748         }
2749
2750         /* Check that feature set is OK for a read-write mount */
2751         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2752                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2753                          "unsupported optional features (%x)",
2754                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2755                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2756                 return 0;
2757         }
2758         /*
2759          * Large file size enabled file system can only be mounted
2760          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2761          */
2762         if (ext4_has_feature_huge_file(sb)) {
2763                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2764                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2765                                  "cannot be mounted RDWR without "
2766                                  "CONFIG_LBDAF");
2767                         return 0;
2768                 }
2769         }
2770         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2771                 ext4_msg(sb, KERN_ERR,
2772                          "Can't support bigalloc feature without "
2773                          "extents feature\n");
2774                 return 0;
2775         }
2776
2777 #ifndef CONFIG_QUOTA
2778         if (ext4_has_feature_quota(sb) && !readonly) {
2779                 ext4_msg(sb, KERN_ERR,
2780                          "Filesystem with quota feature cannot be mounted RDWR "
2781                          "without CONFIG_QUOTA");
2782                 return 0;
2783         }
2784         if (ext4_has_feature_project(sb) && !readonly) {
2785                 ext4_msg(sb, KERN_ERR,
2786                          "Filesystem with project quota feature cannot be mounted RDWR "
2787                          "without CONFIG_QUOTA");
2788                 return 0;
2789         }
2790 #endif  /* CONFIG_QUOTA */
2791         return 1;
2792 }
2793
2794 /*
2795  * This function is called once a day if we have errors logged
2796  * on the file system
2797  */
2798 static void print_daily_error_info(struct timer_list *t)
2799 {
2800         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2801         struct super_block *sb = sbi->s_sb;
2802         struct ext4_super_block *es = sbi->s_es;
2803
2804         if (es->s_error_count)
2805                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2806                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2807                          le32_to_cpu(es->s_error_count));
2808         if (es->s_first_error_time) {
2809                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2810                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2811                        (int) sizeof(es->s_first_error_func),
2812                        es->s_first_error_func,
2813                        le32_to_cpu(es->s_first_error_line));
2814                 if (es->s_first_error_ino)
2815                         printk(KERN_CONT ": inode %u",
2816                                le32_to_cpu(es->s_first_error_ino));
2817                 if (es->s_first_error_block)
2818                         printk(KERN_CONT ": block %llu", (unsigned long long)
2819                                le64_to_cpu(es->s_first_error_block));
2820                 printk(KERN_CONT "\n");
2821         }
2822         if (es->s_last_error_time) {
2823                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2824                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2825                        (int) sizeof(es->s_last_error_func),
2826                        es->s_last_error_func,
2827                        le32_to_cpu(es->s_last_error_line));
2828                 if (es->s_last_error_ino)
2829                         printk(KERN_CONT ": inode %u",
2830                                le32_to_cpu(es->s_last_error_ino));
2831                 if (es->s_last_error_block)
2832                         printk(KERN_CONT ": block %llu", (unsigned long long)
2833                                le64_to_cpu(es->s_last_error_block));
2834                 printk(KERN_CONT "\n");
2835         }
2836         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2837 }
2838
2839 /* Find next suitable group and run ext4_init_inode_table */
2840 static int ext4_run_li_request(struct ext4_li_request *elr)
2841 {
2842         struct ext4_group_desc *gdp = NULL;
2843         ext4_group_t group, ngroups;
2844         struct super_block *sb;
2845         unsigned long timeout = 0;
2846         int ret = 0;
2847
2848         sb = elr->lr_super;
2849         ngroups = EXT4_SB(sb)->s_groups_count;
2850
2851         for (group = elr->lr_next_group; group < ngroups; group++) {
2852                 gdp = ext4_get_group_desc(sb, group, NULL);
2853                 if (!gdp) {
2854                         ret = 1;
2855                         break;
2856                 }
2857
2858                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2859                         break;
2860         }
2861
2862         if (group >= ngroups)
2863                 ret = 1;
2864
2865         if (!ret) {
2866                 timeout = jiffies;
2867                 ret = ext4_init_inode_table(sb, group,
2868                                             elr->lr_timeout ? 0 : 1);
2869                 if (elr->lr_timeout == 0) {
2870                         timeout = (jiffies - timeout) *
2871                                   elr->lr_sbi->s_li_wait_mult;
2872                         elr->lr_timeout = timeout;
2873                 }
2874                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2875                 elr->lr_next_group = group + 1;
2876         }
2877         return ret;
2878 }
2879
2880 /*
2881  * Remove lr_request from the list_request and free the
2882  * request structure. Should be called with li_list_mtx held
2883  */
2884 static void ext4_remove_li_request(struct ext4_li_request *elr)
2885 {
2886         struct ext4_sb_info *sbi;
2887
2888         if (!elr)
2889                 return;
2890
2891         sbi = elr->lr_sbi;
2892
2893         list_del(&elr->lr_request);
2894         sbi->s_li_request = NULL;
2895         kfree(elr);
2896 }
2897
2898 static void ext4_unregister_li_request(struct super_block *sb)
2899 {
2900         mutex_lock(&ext4_li_mtx);
2901         if (!ext4_li_info) {
2902                 mutex_unlock(&ext4_li_mtx);
2903                 return;
2904         }
2905
2906         mutex_lock(&ext4_li_info->li_list_mtx);
2907         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2908         mutex_unlock(&ext4_li_info->li_list_mtx);
2909         mutex_unlock(&ext4_li_mtx);
2910 }
2911
2912 static struct task_struct *ext4_lazyinit_task;
2913
2914 /*
2915  * This is the function where ext4lazyinit thread lives. It walks
2916  * through the request list searching for next scheduled filesystem.
2917  * When such a fs is found, run the lazy initialization request
2918  * (ext4_rn_li_request) and keep track of the time spend in this
2919  * function. Based on that time we compute next schedule time of
2920  * the request. When walking through the list is complete, compute
2921  * next waking time and put itself into sleep.
2922  */
2923 static int ext4_lazyinit_thread(void *arg)
2924 {
2925         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2926         struct list_head *pos, *n;
2927         struct ext4_li_request *elr;
2928         unsigned long next_wakeup, cur;
2929
2930         BUG_ON(NULL == eli);
2931
2932 cont_thread:
2933         while (true) {
2934                 next_wakeup = MAX_JIFFY_OFFSET;
2935
2936                 mutex_lock(&eli->li_list_mtx);
2937                 if (list_empty(&eli->li_request_list)) {
2938                         mutex_unlock(&eli->li_list_mtx);
2939                         goto exit_thread;
2940                 }
2941                 list_for_each_safe(pos, n, &eli->li_request_list) {
2942                         int err = 0;
2943                         int progress = 0;
2944                         elr = list_entry(pos, struct ext4_li_request,
2945                                          lr_request);
2946
2947                         if (time_before(jiffies, elr->lr_next_sched)) {
2948                                 if (time_before(elr->lr_next_sched, next_wakeup))
2949                                         next_wakeup = elr->lr_next_sched;
2950                                 continue;
2951                         }
2952                         if (down_read_trylock(&elr->lr_super->s_umount)) {
2953                                 if (sb_start_write_trylock(elr->lr_super)) {
2954                                         progress = 1;
2955                                         /*
2956                                          * We hold sb->s_umount, sb can not
2957                                          * be removed from the list, it is
2958                                          * now safe to drop li_list_mtx
2959                                          */
2960                                         mutex_unlock(&eli->li_list_mtx);
2961                                         err = ext4_run_li_request(elr);
2962                                         sb_end_write(elr->lr_super);
2963                                         mutex_lock(&eli->li_list_mtx);
2964                                         n = pos->next;
2965                                 }
2966                                 up_read((&elr->lr_super->s_umount));
2967                         }
2968                         /* error, remove the lazy_init job */
2969                         if (err) {
2970                                 ext4_remove_li_request(elr);
2971                                 continue;
2972                         }
2973                         if (!progress) {
2974                                 elr->lr_next_sched = jiffies +
2975                                         (prandom_u32()
2976                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
2977                         }
2978                         if (time_before(elr->lr_next_sched, next_wakeup))
2979                                 next_wakeup = elr->lr_next_sched;
2980                 }
2981                 mutex_unlock(&eli->li_list_mtx);
2982
2983                 try_to_freeze();
2984
2985                 cur = jiffies;
2986                 if ((time_after_eq(cur, next_wakeup)) ||
2987                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2988                         cond_resched();
2989                         continue;
2990                 }
2991
2992                 schedule_timeout_interruptible(next_wakeup - cur);
2993
2994                 if (kthread_should_stop()) {
2995                         ext4_clear_request_list();
2996                         goto exit_thread;
2997                 }
2998         }
2999
3000 exit_thread:
3001         /*
3002          * It looks like the request list is empty, but we need
3003          * to check it under the li_list_mtx lock, to prevent any
3004          * additions into it, and of course we should lock ext4_li_mtx
3005          * to atomically free the list and ext4_li_info, because at
3006          * this point another ext4 filesystem could be registering
3007          * new one.
3008          */
3009         mutex_lock(&ext4_li_mtx);
3010         mutex_lock(&eli->li_list_mtx);
3011         if (!list_empty(&eli->li_request_list)) {
3012                 mutex_unlock(&eli->li_list_mtx);
3013                 mutex_unlock(&ext4_li_mtx);
3014                 goto cont_thread;
3015         }
3016         mutex_unlock(&eli->li_list_mtx);
3017         kfree(ext4_li_info);
3018         ext4_li_info = NULL;
3019         mutex_unlock(&ext4_li_mtx);
3020
3021         return 0;
3022 }
3023
3024 static void ext4_clear_request_list(void)
3025 {
3026         struct list_head *pos, *n;
3027         struct ext4_li_request *elr;
3028
3029         mutex_lock(&ext4_li_info->li_list_mtx);
3030         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3031                 elr = list_entry(pos, struct ext4_li_request,
3032                                  lr_request);
3033                 ext4_remove_li_request(elr);
3034         }
3035         mutex_unlock(&ext4_li_info->li_list_mtx);
3036 }
3037
3038 static int ext4_run_lazyinit_thread(void)
3039 {
3040         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3041                                          ext4_li_info, "ext4lazyinit");
3042         if (IS_ERR(ext4_lazyinit_task)) {
3043                 int err = PTR_ERR(ext4_lazyinit_task);
3044                 ext4_clear_request_list();
3045                 kfree(ext4_li_info);
3046                 ext4_li_info = NULL;
3047                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3048                                  "initialization thread\n",
3049                                  err);
3050                 return err;
3051         }
3052         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3053         return 0;
3054 }
3055
3056 /*
3057  * Check whether it make sense to run itable init. thread or not.
3058  * If there is at least one uninitialized inode table, return
3059  * corresponding group number, else the loop goes through all
3060  * groups and return total number of groups.
3061  */
3062 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3063 {
3064         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3065         struct ext4_group_desc *gdp = NULL;
3066
3067         for (group = 0; group < ngroups; group++) {
3068                 gdp = ext4_get_group_desc(sb, group, NULL);
3069                 if (!gdp)
3070                         continue;
3071
3072                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3073                         break;
3074         }
3075
3076         return group;
3077 }
3078
3079 static int ext4_li_info_new(void)
3080 {
3081         struct ext4_lazy_init *eli = NULL;
3082
3083         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3084         if (!eli)
3085                 return -ENOMEM;
3086
3087         INIT_LIST_HEAD(&eli->li_request_list);
3088         mutex_init(&eli->li_list_mtx);
3089
3090         eli->li_state |= EXT4_LAZYINIT_QUIT;
3091
3092         ext4_li_info = eli;
3093
3094         return 0;
3095 }
3096
3097 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3098                                             ext4_group_t start)
3099 {
3100         struct ext4_sb_info *sbi = EXT4_SB(sb);
3101         struct ext4_li_request *elr;
3102
3103         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3104         if (!elr)
3105                 return NULL;
3106
3107         elr->lr_super = sb;
3108         elr->lr_sbi = sbi;
3109         elr->lr_next_group = start;
3110
3111         /*
3112          * Randomize first schedule time of the request to
3113          * spread the inode table initialization requests
3114          * better.
3115          */
3116         elr->lr_next_sched = jiffies + (prandom_u32() %
3117                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3118         return elr;
3119 }
3120
3121 int ext4_register_li_request(struct super_block *sb,
3122                              ext4_group_t first_not_zeroed)
3123 {
3124         struct ext4_sb_info *sbi = EXT4_SB(sb);
3125         struct ext4_li_request *elr = NULL;
3126         ext4_group_t ngroups = sbi->s_groups_count;
3127         int ret = 0;
3128
3129         mutex_lock(&ext4_li_mtx);
3130         if (sbi->s_li_request != NULL) {
3131                 /*
3132                  * Reset timeout so it can be computed again, because
3133                  * s_li_wait_mult might have changed.
3134                  */
3135                 sbi->s_li_request->lr_timeout = 0;
3136                 goto out;
3137         }
3138
3139         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3140             !test_opt(sb, INIT_INODE_TABLE))
3141                 goto out;
3142
3143         elr = ext4_li_request_new(sb, first_not_zeroed);
3144         if (!elr) {
3145                 ret = -ENOMEM;
3146                 goto out;
3147         }
3148
3149         if (NULL == ext4_li_info) {
3150                 ret = ext4_li_info_new();
3151                 if (ret)
3152                         goto out;
3153         }
3154
3155         mutex_lock(&ext4_li_info->li_list_mtx);
3156         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3157         mutex_unlock(&ext4_li_info->li_list_mtx);
3158
3159         sbi->s_li_request = elr;
3160         /*
3161          * set elr to NULL here since it has been inserted to
3162          * the request_list and the removal and free of it is
3163          * handled by ext4_clear_request_list from now on.
3164          */
3165         elr = NULL;
3166
3167         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3168                 ret = ext4_run_lazyinit_thread();
3169                 if (ret)
3170                         goto out;
3171         }
3172 out:
3173         mutex_unlock(&ext4_li_mtx);
3174         if (ret)
3175                 kfree(elr);
3176         return ret;
3177 }
3178
3179 /*
3180  * We do not need to lock anything since this is called on
3181  * module unload.
3182  */
3183 static void ext4_destroy_lazyinit_thread(void)
3184 {
3185         /*
3186          * If thread exited earlier
3187          * there's nothing to be done.
3188          */
3189         if (!ext4_li_info || !ext4_lazyinit_task)
3190                 return;
3191
3192         kthread_stop(ext4_lazyinit_task);
3193 }
3194
3195 static int set_journal_csum_feature_set(struct super_block *sb)
3196 {
3197         int ret = 1;
3198         int compat, incompat;
3199         struct ext4_sb_info *sbi = EXT4_SB(sb);
3200
3201         if (ext4_has_metadata_csum(sb)) {
3202                 /* journal checksum v3 */
3203                 compat = 0;
3204                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3205         } else {
3206                 /* journal checksum v1 */
3207                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3208                 incompat = 0;
3209         }
3210
3211         jbd2_journal_clear_features(sbi->s_journal,
3212                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3213                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3214                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3215         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3216                 ret = jbd2_journal_set_features(sbi->s_journal,
3217                                 compat, 0,
3218                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3219                                 incompat);
3220         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3221                 ret = jbd2_journal_set_features(sbi->s_journal,
3222                                 compat, 0,
3223                                 incompat);
3224                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3225                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3226         } else {
3227                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3228                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3229         }
3230
3231         return ret;
3232 }
3233
3234 /*
3235  * Note: calculating the overhead so we can be compatible with
3236  * historical BSD practice is quite difficult in the face of
3237  * clusters/bigalloc.  This is because multiple metadata blocks from
3238  * different block group can end up in the same allocation cluster.
3239  * Calculating the exact overhead in the face of clustered allocation
3240  * requires either O(all block bitmaps) in memory or O(number of block
3241  * groups**2) in time.  We will still calculate the superblock for
3242  * older file systems --- and if we come across with a bigalloc file
3243  * system with zero in s_overhead_clusters the estimate will be close to
3244  * correct especially for very large cluster sizes --- but for newer
3245  * file systems, it's better to calculate this figure once at mkfs
3246  * time, and store it in the superblock.  If the superblock value is
3247  * present (even for non-bigalloc file systems), we will use it.
3248  */
3249 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3250                           char *buf)
3251 {
3252         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3253         struct ext4_group_desc  *gdp;
3254         ext4_fsblk_t            first_block, last_block, b;
3255         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3256         int                     s, j, count = 0;
3257
3258         if (!ext4_has_feature_bigalloc(sb))
3259                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3260                         sbi->s_itb_per_group + 2);
3261
3262         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3263                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3264         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3265         for (i = 0; i < ngroups; i++) {
3266                 gdp = ext4_get_group_desc(sb, i, NULL);
3267                 b = ext4_block_bitmap(sb, gdp);
3268                 if (b >= first_block && b <= last_block) {
3269                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3270                         count++;
3271                 }
3272                 b = ext4_inode_bitmap(sb, gdp);
3273                 if (b >= first_block && b <= last_block) {
3274                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3275                         count++;
3276                 }
3277                 b = ext4_inode_table(sb, gdp);
3278                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3279                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3280                                 int c = EXT4_B2C(sbi, b - first_block);
3281                                 ext4_set_bit(c, buf);
3282                                 count++;
3283                         }
3284                 if (i != grp)
3285                         continue;
3286                 s = 0;
3287                 if (ext4_bg_has_super(sb, grp)) {
3288                         ext4_set_bit(s++, buf);
3289                         count++;
3290                 }
3291                 j = ext4_bg_num_gdb(sb, grp);
3292                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3293                         ext4_error(sb, "Invalid number of block group "
3294                                    "descriptor blocks: %d", j);
3295                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3296                 }
3297                 count += j;
3298                 for (; j > 0; j--)
3299                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3300         }
3301         if (!count)
3302                 return 0;
3303         return EXT4_CLUSTERS_PER_GROUP(sb) -
3304                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3305 }
3306
3307 /*
3308  * Compute the overhead and stash it in sbi->s_overhead
3309  */
3310 int ext4_calculate_overhead(struct super_block *sb)
3311 {
3312         struct ext4_sb_info *sbi = EXT4_SB(sb);
3313         struct ext4_super_block *es = sbi->s_es;
3314         struct inode *j_inode;
3315         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3316         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3317         ext4_fsblk_t overhead = 0;
3318         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3319
3320         if (!buf)
3321                 return -ENOMEM;
3322
3323         /*
3324          * Compute the overhead (FS structures).  This is constant
3325          * for a given filesystem unless the number of block groups
3326          * changes so we cache the previous value until it does.
3327          */
3328
3329         /*
3330          * All of the blocks before first_data_block are overhead
3331          */
3332         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3333
3334         /*
3335          * Add the overhead found in each block group
3336          */
3337         for (i = 0; i < ngroups; i++) {
3338                 int blks;
3339
3340                 blks = count_overhead(sb, i, buf);
3341                 overhead += blks;
3342                 if (blks)
3343                         memset(buf, 0, PAGE_SIZE);
3344                 cond_resched();
3345         }
3346
3347         /*
3348          * Add the internal journal blocks whether the journal has been
3349          * loaded or not
3350          */
3351         if (sbi->s_journal && !sbi->journal_bdev)
3352                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3353         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3354                 j_inode = ext4_get_journal_inode(sb, j_inum);
3355                 if (j_inode) {
3356                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3357                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3358                         iput(j_inode);
3359                 } else {
3360                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3361                 }
3362         }
3363         sbi->s_overhead = overhead;
3364         smp_wmb();
3365         free_page((unsigned long) buf);
3366         return 0;
3367 }
3368
3369 static void ext4_set_resv_clusters(struct super_block *sb)
3370 {
3371         ext4_fsblk_t resv_clusters;
3372         struct ext4_sb_info *sbi = EXT4_SB(sb);
3373
3374         /*
3375          * There's no need to reserve anything when we aren't using extents.
3376          * The space estimates are exact, there are no unwritten extents,
3377          * hole punching doesn't need new metadata... This is needed especially
3378          * to keep ext2/3 backward compatibility.
3379          */
3380         if (!ext4_has_feature_extents(sb))
3381                 return;
3382         /*
3383          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3384          * This should cover the situations where we can not afford to run
3385          * out of space like for example punch hole, or converting
3386          * unwritten extents in delalloc path. In most cases such
3387          * allocation would require 1, or 2 blocks, higher numbers are
3388          * very rare.
3389          */
3390         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3391                          sbi->s_cluster_bits);
3392
3393         do_div(resv_clusters, 50);
3394         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3395
3396         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3397 }
3398
3399 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3400 {
3401         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3402         char *orig_data = kstrdup(data, GFP_KERNEL);
3403         struct buffer_head *bh;
3404         struct ext4_super_block *es = NULL;
3405         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3406         ext4_fsblk_t block;
3407         ext4_fsblk_t sb_block = get_sb_block(&data);
3408         ext4_fsblk_t logical_sb_block;
3409         unsigned long offset = 0;
3410         unsigned long journal_devnum = 0;
3411         unsigned long def_mount_opts;
3412         struct inode *root;
3413         const char *descr;
3414         int ret = -ENOMEM;
3415         int blocksize, clustersize;
3416         unsigned int db_count;
3417         unsigned int i;
3418         int needs_recovery, has_huge_files, has_bigalloc;
3419         __u64 blocks_count;
3420         int err = 0;
3421         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3422         ext4_group_t first_not_zeroed;
3423
3424         if ((data && !orig_data) || !sbi)
3425                 goto out_free_base;
3426
3427         sbi->s_daxdev = dax_dev;
3428         sbi->s_blockgroup_lock =
3429                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3430         if (!sbi->s_blockgroup_lock)
3431                 goto out_free_base;
3432
3433         sb->s_fs_info = sbi;
3434         sbi->s_sb = sb;
3435         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3436         sbi->s_sb_block = sb_block;
3437         if (sb->s_bdev->bd_part)
3438                 sbi->s_sectors_written_start =
3439                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3440
3441         /* Cleanup superblock name */
3442         strreplace(sb->s_id, '/', '!');
3443
3444         /* -EINVAL is default */
3445         ret = -EINVAL;
3446         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3447         if (!blocksize) {
3448                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3449                 goto out_fail;
3450         }
3451
3452         /*
3453          * The ext4 superblock will not be buffer aligned for other than 1kB
3454          * block sizes.  We need to calculate the offset from buffer start.
3455          */
3456         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3457                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3458                 offset = do_div(logical_sb_block, blocksize);
3459         } else {
3460                 logical_sb_block = sb_block;
3461         }
3462
3463         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3464                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3465                 goto out_fail;
3466         }
3467         /*
3468          * Note: s_es must be initialized as soon as possible because
3469          *       some ext4 macro-instructions depend on its value
3470          */
3471         es = (struct ext4_super_block *) (bh->b_data + offset);
3472         sbi->s_es = es;
3473         sb->s_magic = le16_to_cpu(es->s_magic);
3474         if (sb->s_magic != EXT4_SUPER_MAGIC)
3475                 goto cantfind_ext4;
3476         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3477
3478         /* Warn if metadata_csum and gdt_csum are both set. */
3479         if (ext4_has_feature_metadata_csum(sb) &&
3480             ext4_has_feature_gdt_csum(sb))
3481                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3482                              "redundant flags; please run fsck.");
3483
3484         /* Check for a known checksum algorithm */
3485         if (!ext4_verify_csum_type(sb, es)) {
3486                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3487                          "unknown checksum algorithm.");
3488                 silent = 1;
3489                 goto cantfind_ext4;
3490         }
3491
3492         /* Load the checksum driver */
3493         if (ext4_has_feature_metadata_csum(sb) ||
3494             ext4_has_feature_ea_inode(sb)) {
3495                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3496                 if (IS_ERR(sbi->s_chksum_driver)) {
3497                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3498                         ret = PTR_ERR(sbi->s_chksum_driver);
3499                         sbi->s_chksum_driver = NULL;
3500                         goto failed_mount;
3501                 }
3502         }
3503
3504         /* Check superblock checksum */
3505         if (!ext4_superblock_csum_verify(sb, es)) {
3506                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3507                          "invalid superblock checksum.  Run e2fsck?");
3508                 silent = 1;
3509                 ret = -EFSBADCRC;
3510                 goto cantfind_ext4;
3511         }
3512
3513         /* Precompute checksum seed for all metadata */
3514         if (ext4_has_feature_csum_seed(sb))
3515                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3516         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3517                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3518                                                sizeof(es->s_uuid));
3519
3520         /* Set defaults before we parse the mount options */
3521         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3522         set_opt(sb, INIT_INODE_TABLE);
3523         if (def_mount_opts & EXT4_DEFM_DEBUG)
3524                 set_opt(sb, DEBUG);
3525         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3526                 set_opt(sb, GRPID);
3527         if (def_mount_opts & EXT4_DEFM_UID16)
3528                 set_opt(sb, NO_UID32);
3529         /* xattr user namespace & acls are now defaulted on */
3530         set_opt(sb, XATTR_USER);
3531 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3532         set_opt(sb, POSIX_ACL);
3533 #endif
3534         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3535         if (ext4_has_metadata_csum(sb))
3536                 set_opt(sb, JOURNAL_CHECKSUM);
3537
3538         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3539                 set_opt(sb, JOURNAL_DATA);
3540         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3541                 set_opt(sb, ORDERED_DATA);
3542         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3543                 set_opt(sb, WRITEBACK_DATA);
3544
3545         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3546                 set_opt(sb, ERRORS_PANIC);
3547         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3548                 set_opt(sb, ERRORS_CONT);
3549         else
3550                 set_opt(sb, ERRORS_RO);
3551         /* block_validity enabled by default; disable with noblock_validity */
3552         set_opt(sb, BLOCK_VALIDITY);
3553         if (def_mount_opts & EXT4_DEFM_DISCARD)
3554                 set_opt(sb, DISCARD);
3555
3556         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3557         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3558         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3559         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3560         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3561
3562         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3563                 set_opt(sb, BARRIER);
3564
3565         /*
3566          * enable delayed allocation by default
3567          * Use -o nodelalloc to turn it off
3568          */
3569         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3570             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3571                 set_opt(sb, DELALLOC);
3572
3573         /*
3574          * set default s_li_wait_mult for lazyinit, for the case there is
3575          * no mount option specified.
3576          */
3577         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3578
3579         if (sbi->s_es->s_mount_opts[0]) {
3580                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3581                                               sizeof(sbi->s_es->s_mount_opts),
3582                                               GFP_KERNEL);
3583                 if (!s_mount_opts)
3584                         goto failed_mount;
3585                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3586                                    &journal_ioprio, 0)) {
3587                         ext4_msg(sb, KERN_WARNING,
3588                                  "failed to parse options in superblock: %s",
3589                                  s_mount_opts);
3590                 }
3591                 kfree(s_mount_opts);
3592         }
3593         sbi->s_def_mount_opt = sbi->s_mount_opt;
3594         if (!parse_options((char *) data, sb, &journal_devnum,
3595                            &journal_ioprio, 0))
3596                 goto failed_mount;
3597
3598         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3599                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3600                             "with data=journal disables delayed "
3601                             "allocation and O_DIRECT support!\n");
3602                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3603                         ext4_msg(sb, KERN_ERR, "can't mount with "
3604                                  "both data=journal and delalloc");
3605                         goto failed_mount;
3606                 }
3607                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3608                         ext4_msg(sb, KERN_ERR, "can't mount with "
3609                                  "both data=journal and dioread_nolock");
3610                         goto failed_mount;
3611                 }
3612                 if (test_opt(sb, DAX)) {
3613                         ext4_msg(sb, KERN_ERR, "can't mount with "
3614                                  "both data=journal and dax");
3615                         goto failed_mount;
3616                 }
3617                 if (ext4_has_feature_encrypt(sb)) {
3618                         ext4_msg(sb, KERN_WARNING,
3619                                  "encrypted files will use data=ordered "
3620                                  "instead of data journaling mode");
3621                 }
3622                 if (test_opt(sb, DELALLOC))
3623                         clear_opt(sb, DELALLOC);
3624         } else {
3625                 sb->s_iflags |= SB_I_CGROUPWB;
3626         }
3627
3628         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3629                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3630
3631         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3632             (ext4_has_compat_features(sb) ||
3633              ext4_has_ro_compat_features(sb) ||
3634              ext4_has_incompat_features(sb)))
3635                 ext4_msg(sb, KERN_WARNING,
3636                        "feature flags set on rev 0 fs, "
3637                        "running e2fsck is recommended");
3638
3639         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3640                 set_opt2(sb, HURD_COMPAT);
3641                 if (ext4_has_feature_64bit(sb)) {
3642                         ext4_msg(sb, KERN_ERR,
3643                                  "The Hurd can't support 64-bit file systems");
3644                         goto failed_mount;
3645                 }
3646
3647                 /*
3648                  * ea_inode feature uses l_i_version field which is not
3649                  * available in HURD_COMPAT mode.
3650                  */
3651                 if (ext4_has_feature_ea_inode(sb)) {
3652                         ext4_msg(sb, KERN_ERR,
3653                                  "ea_inode feature is not supported for Hurd");
3654                         goto failed_mount;
3655                 }
3656         }
3657
3658         if (IS_EXT2_SB(sb)) {
3659                 if (ext2_feature_set_ok(sb))
3660                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3661                                  "using the ext4 subsystem");
3662                 else {
3663                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3664                                  "to feature incompatibilities");
3665                         goto failed_mount;
3666                 }
3667         }
3668
3669         if (IS_EXT3_SB(sb)) {
3670                 if (ext3_feature_set_ok(sb))
3671                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3672                                  "using the ext4 subsystem");
3673                 else {
3674                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3675                                  "to feature incompatibilities");
3676                         goto failed_mount;
3677                 }
3678         }
3679
3680         /*
3681          * Check feature flags regardless of the revision level, since we
3682          * previously didn't change the revision level when setting the flags,
3683          * so there is a chance incompat flags are set on a rev 0 filesystem.
3684          */
3685         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3686                 goto failed_mount;
3687
3688         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3689         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3690             blocksize > EXT4_MAX_BLOCK_SIZE) {
3691                 ext4_msg(sb, KERN_ERR,
3692                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3693                          blocksize, le32_to_cpu(es->s_log_block_size));
3694                 goto failed_mount;
3695         }
3696         if (le32_to_cpu(es->s_log_block_size) >
3697             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3698                 ext4_msg(sb, KERN_ERR,
3699                          "Invalid log block size: %u",
3700                          le32_to_cpu(es->s_log_block_size));
3701                 goto failed_mount;
3702         }
3703
3704         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3705                 ext4_msg(sb, KERN_ERR,
3706                          "Number of reserved GDT blocks insanely large: %d",
3707                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3708                 goto failed_mount;
3709         }
3710
3711         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3712                 if (ext4_has_feature_inline_data(sb)) {
3713                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
3714                                         " that may contain inline data");
3715                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3716                 }
3717                 err = bdev_dax_supported(sb, blocksize);
3718                 if (err) {
3719                         ext4_msg(sb, KERN_ERR,
3720                                 "DAX unsupported by block device. Turning off DAX.");
3721                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX;
3722                 }
3723         }
3724
3725         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3726                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3727                          es->s_encryption_level);
3728                 goto failed_mount;
3729         }
3730
3731         if (sb->s_blocksize != blocksize) {
3732                 /* Validate the filesystem blocksize */
3733                 if (!sb_set_blocksize(sb, blocksize)) {
3734                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3735                                         blocksize);
3736                         goto failed_mount;
3737                 }
3738
3739                 brelse(bh);
3740                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3741                 offset = do_div(logical_sb_block, blocksize);
3742                 bh = sb_bread_unmovable(sb, logical_sb_block);
3743                 if (!bh) {
3744                         ext4_msg(sb, KERN_ERR,
3745                                "Can't read superblock on 2nd try");
3746                         goto failed_mount;
3747                 }
3748                 es = (struct ext4_super_block *)(bh->b_data + offset);
3749                 sbi->s_es = es;
3750                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3751                         ext4_msg(sb, KERN_ERR,
3752                                "Magic mismatch, very weird!");
3753                         goto failed_mount;
3754                 }
3755         }
3756
3757         has_huge_files = ext4_has_feature_huge_file(sb);
3758         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3759                                                       has_huge_files);
3760         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3761
3762         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3763                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3764                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3765         } else {
3766                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3767                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3768                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3769                     (!is_power_of_2(sbi->s_inode_size)) ||
3770                     (sbi->s_inode_size > blocksize)) {
3771                         ext4_msg(sb, KERN_ERR,
3772                                "unsupported inode size: %d",
3773                                sbi->s_inode_size);
3774                         goto failed_mount;
3775                 }
3776                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3777                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3778         }
3779
3780         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3781         if (ext4_has_feature_64bit(sb)) {
3782                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3783                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3784                     !is_power_of_2(sbi->s_desc_size)) {
3785                         ext4_msg(sb, KERN_ERR,
3786                                "unsupported descriptor size %lu",
3787                                sbi->s_desc_size);
3788                         goto failed_mount;
3789                 }
3790         } else
3791                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3792
3793         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3794         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3795
3796         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3797         if (sbi->s_inodes_per_block == 0)
3798                 goto cantfind_ext4;
3799         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
3800             sbi->s_inodes_per_group > blocksize * 8) {
3801                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
3802                          sbi->s_blocks_per_group);
3803                 goto failed_mount;
3804         }
3805         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3806                                         sbi->s_inodes_per_block;
3807         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3808         sbi->s_sbh = bh;
3809         sbi->s_mount_state = le16_to_cpu(es->s_state);
3810         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3811         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3812
3813         for (i = 0; i < 4; i++)
3814                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3815         sbi->s_def_hash_version = es->s_def_hash_version;
3816         if (ext4_has_feature_dir_index(sb)) {
3817                 i = le32_to_cpu(es->s_flags);
3818                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3819                         sbi->s_hash_unsigned = 3;
3820                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3821 #ifdef __CHAR_UNSIGNED__
3822                         if (!sb_rdonly(sb))
3823                                 es->s_flags |=
3824                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3825                         sbi->s_hash_unsigned = 3;
3826 #else
3827                         if (!sb_rdonly(sb))
3828                                 es->s_flags |=
3829                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3830 #endif
3831                 }
3832         }
3833
3834         /* Handle clustersize */
3835         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3836         has_bigalloc = ext4_has_feature_bigalloc(sb);
3837         if (has_bigalloc) {
3838                 if (clustersize < blocksize) {
3839                         ext4_msg(sb, KERN_ERR,
3840                                  "cluster size (%d) smaller than "
3841                                  "block size (%d)", clustersize, blocksize);
3842                         goto failed_mount;
3843                 }
3844                 if (le32_to_cpu(es->s_log_cluster_size) >
3845                     (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3846                         ext4_msg(sb, KERN_ERR,
3847                                  "Invalid log cluster size: %u",
3848                                  le32_to_cpu(es->s_log_cluster_size));
3849                         goto failed_mount;
3850                 }
3851                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3852                         le32_to_cpu(es->s_log_block_size);
3853                 sbi->s_clusters_per_group =
3854                         le32_to_cpu(es->s_clusters_per_group);
3855                 if (sbi->s_clusters_per_group > blocksize * 8) {
3856                         ext4_msg(sb, KERN_ERR,
3857                                  "#clusters per group too big: %lu",
3858                                  sbi->s_clusters_per_group);
3859                         goto failed_mount;
3860                 }
3861                 if (sbi->s_blocks_per_group !=
3862                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3863                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3864                                  "clusters per group (%lu) inconsistent",
3865                                  sbi->s_blocks_per_group,
3866                                  sbi->s_clusters_per_group);
3867                         goto failed_mount;
3868                 }
3869         } else {
3870                 if (clustersize != blocksize) {
3871                         ext4_warning(sb, "fragment/cluster size (%d) != "
3872                                      "block size (%d)", clustersize,
3873                                      blocksize);
3874                         clustersize = blocksize;
3875                 }
3876                 if (sbi->s_blocks_per_group > blocksize * 8) {
3877                         ext4_msg(sb, KERN_ERR,
3878                                  "#blocks per group too big: %lu",
3879                                  sbi->s_blocks_per_group);
3880                         goto failed_mount;
3881                 }
3882                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3883                 sbi->s_cluster_bits = 0;
3884         }
3885         sbi->s_cluster_ratio = clustersize / blocksize;
3886
3887         /* Do we have standard group size of clustersize * 8 blocks ? */
3888         if (sbi->s_blocks_per_group == clustersize << 3)
3889                 set_opt2(sb, STD_GROUP_SIZE);
3890
3891         /*
3892          * Test whether we have more sectors than will fit in sector_t,
3893          * and whether the max offset is addressable by the page cache.
3894          */
3895         err = generic_check_addressable(sb->s_blocksize_bits,
3896                                         ext4_blocks_count(es));
3897         if (err) {
3898                 ext4_msg(sb, KERN_ERR, "filesystem"
3899                          " too large to mount safely on this system");
3900                 if (sizeof(sector_t) < 8)
3901                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3902                 goto failed_mount;
3903         }
3904
3905         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3906                 goto cantfind_ext4;
3907
3908         /* check blocks count against device size */
3909         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3910         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3911                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3912                        "exceeds size of device (%llu blocks)",
3913                        ext4_blocks_count(es), blocks_count);
3914                 goto failed_mount;
3915         }
3916
3917         /*
3918          * It makes no sense for the first data block to be beyond the end
3919          * of the filesystem.
3920          */
3921         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3922                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3923                          "block %u is beyond end of filesystem (%llu)",
3924                          le32_to_cpu(es->s_first_data_block),
3925                          ext4_blocks_count(es));
3926                 goto failed_mount;
3927         }
3928         blocks_count = (ext4_blocks_count(es) -
3929                         le32_to_cpu(es->s_first_data_block) +
3930                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3931         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3932         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3933                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3934                        "(block count %llu, first data block %u, "
3935                        "blocks per group %lu)", sbi->s_groups_count,
3936                        ext4_blocks_count(es),
3937                        le32_to_cpu(es->s_first_data_block),
3938                        EXT4_BLOCKS_PER_GROUP(sb));
3939                 goto failed_mount;
3940         }
3941         sbi->s_groups_count = blocks_count;
3942         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3943                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3944         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3945                    EXT4_DESC_PER_BLOCK(sb);
3946         if (ext4_has_feature_meta_bg(sb)) {
3947                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
3948                         ext4_msg(sb, KERN_WARNING,
3949                                  "first meta block group too large: %u "
3950                                  "(group descriptor block count %u)",
3951                                  le32_to_cpu(es->s_first_meta_bg), db_count);
3952                         goto failed_mount;
3953                 }
3954         }
3955         sbi->s_group_desc = kvmalloc(db_count *
3956                                           sizeof(struct buffer_head *),
3957                                           GFP_KERNEL);
3958         if (sbi->s_group_desc == NULL) {
3959                 ext4_msg(sb, KERN_ERR, "not enough memory");
3960                 ret = -ENOMEM;
3961                 goto failed_mount;
3962         }
3963
3964         bgl_lock_init(sbi->s_blockgroup_lock);
3965
3966         /* Pre-read the descriptors into the buffer cache */
3967         for (i = 0; i < db_count; i++) {
3968                 block = descriptor_loc(sb, logical_sb_block, i);
3969                 sb_breadahead(sb, block);
3970         }
3971
3972         for (i = 0; i < db_count; i++) {
3973                 block = descriptor_loc(sb, logical_sb_block, i);
3974                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3975                 if (!sbi->s_group_desc[i]) {
3976                         ext4_msg(sb, KERN_ERR,
3977                                "can't read group descriptor %d", i);
3978                         db_count = i;
3979                         goto failed_mount2;
3980                 }
3981         }
3982         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
3983                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3984                 ret = -EFSCORRUPTED;
3985                 goto failed_mount2;
3986         }
3987
3988         sbi->s_gdb_count = db_count;
3989
3990         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
3991
3992         /* Register extent status tree shrinker */
3993         if (ext4_es_register_shrinker(sbi))
3994                 goto failed_mount3;
3995
3996         sbi->s_stripe = ext4_get_stripe_size(sbi);
3997         sbi->s_extent_max_zeroout_kb = 32;
3998
3999         /*
4000          * set up enough so that it can read an inode
4001          */
4002         sb->s_op = &ext4_sops;
4003         sb->s_export_op = &ext4_export_ops;
4004         sb->s_xattr = ext4_xattr_handlers;
4005 #ifdef CONFIG_EXT4_FS_ENCRYPTION
4006         sb->s_cop = &ext4_cryptops;
4007 #endif
4008 #ifdef CONFIG_QUOTA
4009         sb->dq_op = &ext4_quota_operations;
4010         if (ext4_has_feature_quota(sb))
4011                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4012         else
4013                 sb->s_qcop = &ext4_qctl_operations;
4014         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4015 #endif
4016         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4017
4018         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4019         mutex_init(&sbi->s_orphan_lock);
4020
4021         sb->s_root = NULL;
4022
4023         needs_recovery = (es->s_last_orphan != 0 ||
4024                           ext4_has_feature_journal_needs_recovery(sb));
4025
4026         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4027                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4028                         goto failed_mount3a;
4029
4030         /*
4031          * The first inode we look at is the journal inode.  Don't try
4032          * root first: it may be modified in the journal!
4033          */
4034         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4035                 err = ext4_load_journal(sb, es, journal_devnum);
4036                 if (err)
4037                         goto failed_mount3a;
4038         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4039                    ext4_has_feature_journal_needs_recovery(sb)) {
4040                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4041                        "suppressed and not mounted read-only");
4042                 goto failed_mount_wq;
4043         } else {
4044                 /* Nojournal mode, all journal mount options are illegal */
4045                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4046                         ext4_msg(sb, KERN_ERR, "can't mount with "
4047                                  "journal_checksum, fs mounted w/o journal");
4048                         goto failed_mount_wq;
4049                 }
4050                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4051                         ext4_msg(sb, KERN_ERR, "can't mount with "
4052                                  "journal_async_commit, fs mounted w/o journal");
4053                         goto failed_mount_wq;
4054                 }
4055                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4056                         ext4_msg(sb, KERN_ERR, "can't mount with "
4057                                  "commit=%lu, fs mounted w/o journal",
4058                                  sbi->s_commit_interval / HZ);
4059                         goto failed_mount_wq;
4060                 }
4061                 if (EXT4_MOUNT_DATA_FLAGS &
4062                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4063                         ext4_msg(sb, KERN_ERR, "can't mount with "
4064                                  "data=, fs mounted w/o journal");
4065                         goto failed_mount_wq;
4066                 }
4067                 sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
4068                 clear_opt(sb, JOURNAL_CHECKSUM);
4069                 clear_opt(sb, DATA_FLAGS);
4070                 sbi->s_journal = NULL;
4071                 needs_recovery = 0;
4072                 goto no_journal;
4073         }
4074
4075         if (ext4_has_feature_64bit(sb) &&
4076             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4077                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4078                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4079                 goto failed_mount_wq;
4080         }
4081
4082         if (!set_journal_csum_feature_set(sb)) {
4083                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4084                          "feature set");
4085                 goto failed_mount_wq;
4086         }
4087
4088         /* We have now updated the journal if required, so we can
4089          * validate the data journaling mode. */
4090         switch (test_opt(sb, DATA_FLAGS)) {
4091         case 0:
4092                 /* No mode set, assume a default based on the journal
4093                  * capabilities: ORDERED_DATA if the journal can
4094                  * cope, else JOURNAL_DATA
4095                  */
4096                 if (jbd2_journal_check_available_features
4097                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4098                         set_opt(sb, ORDERED_DATA);
4099                 else
4100                         set_opt(sb, JOURNAL_DATA);
4101                 break;
4102
4103         case EXT4_MOUNT_ORDERED_DATA:
4104         case EXT4_MOUNT_WRITEBACK_DATA:
4105                 if (!jbd2_journal_check_available_features
4106                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4107                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4108                                "requested data journaling mode");
4109                         goto failed_mount_wq;
4110                 }
4111         default:
4112                 break;
4113         }
4114
4115         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4116             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4117                 ext4_msg(sb, KERN_ERR, "can't mount with "
4118                         "journal_async_commit in data=ordered mode");
4119                 goto failed_mount_wq;
4120         }
4121
4122         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4123
4124         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4125
4126 no_journal:
4127         if (!test_opt(sb, NO_MBCACHE)) {
4128                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4129                 if (!sbi->s_ea_block_cache) {
4130                         ext4_msg(sb, KERN_ERR,
4131                                  "Failed to create ea_block_cache");
4132                         goto failed_mount_wq;
4133                 }
4134
4135                 if (ext4_has_feature_ea_inode(sb)) {
4136                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4137                         if (!sbi->s_ea_inode_cache) {
4138                                 ext4_msg(sb, KERN_ERR,
4139                                          "Failed to create ea_inode_cache");
4140                                 goto failed_mount_wq;
4141                         }
4142                 }
4143         }
4144
4145         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4146             (blocksize != PAGE_SIZE)) {
4147                 ext4_msg(sb, KERN_ERR,
4148                          "Unsupported blocksize for fs encryption");
4149                 goto failed_mount_wq;
4150         }
4151
4152         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4153             !ext4_has_feature_encrypt(sb)) {
4154                 ext4_set_feature_encrypt(sb);
4155                 ext4_commit_super(sb, 1);
4156         }
4157
4158         /*
4159          * Get the # of file system overhead blocks from the
4160          * superblock if present.
4161          */
4162         if (es->s_overhead_clusters)
4163                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4164         else {
4165                 err = ext4_calculate_overhead(sb);
4166                 if (err)
4167                         goto failed_mount_wq;
4168         }
4169
4170         /*
4171          * The maximum number of concurrent works can be high and
4172          * concurrency isn't really necessary.  Limit it to 1.
4173          */
4174         EXT4_SB(sb)->rsv_conversion_wq =
4175                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4176         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4177                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4178                 ret = -ENOMEM;
4179                 goto failed_mount4;
4180         }
4181
4182         /*
4183          * The jbd2_journal_load will have done any necessary log recovery,
4184          * so we can safely mount the rest of the filesystem now.
4185          */
4186
4187         root = ext4_iget(sb, EXT4_ROOT_INO);
4188         if (IS_ERR(root)) {
4189                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4190                 ret = PTR_ERR(root);
4191                 root = NULL;
4192                 goto failed_mount4;
4193         }
4194         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4195                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4196                 iput(root);
4197                 goto failed_mount4;
4198         }
4199         sb->s_root = d_make_root(root);
4200         if (!sb->s_root) {
4201                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4202                 ret = -ENOMEM;
4203                 goto failed_mount4;
4204         }
4205
4206         if (ext4_setup_super(sb, es, sb_rdonly(sb)))
4207                 sb->s_flags |= SB_RDONLY;
4208
4209         /* determine the minimum size of new large inodes, if present */
4210         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
4211             sbi->s_want_extra_isize == 0) {
4212                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4213                                                      EXT4_GOOD_OLD_INODE_SIZE;
4214                 if (ext4_has_feature_extra_isize(sb)) {
4215                         if (sbi->s_want_extra_isize <
4216                             le16_to_cpu(es->s_want_extra_isize))
4217                                 sbi->s_want_extra_isize =
4218                                         le16_to_cpu(es->s_want_extra_isize);
4219                         if (sbi->s_want_extra_isize <
4220                             le16_to_cpu(es->s_min_extra_isize))
4221                                 sbi->s_want_extra_isize =
4222                                         le16_to_cpu(es->s_min_extra_isize);
4223                 }
4224         }
4225         /* Check if enough inode space is available */
4226         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4227                                                         sbi->s_inode_size) {
4228                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4229                                                        EXT4_GOOD_OLD_INODE_SIZE;
4230                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4231                          "available");
4232         }
4233
4234         ext4_set_resv_clusters(sb);
4235
4236         err = ext4_setup_system_zone(sb);
4237         if (err) {
4238                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4239                          "zone (%d)", err);
4240                 goto failed_mount4a;
4241         }
4242
4243         ext4_ext_init(sb);
4244         err = ext4_mb_init(sb);
4245         if (err) {
4246                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4247                          err);
4248                 goto failed_mount5;
4249         }
4250
4251         block = ext4_count_free_clusters(sb);
4252         ext4_free_blocks_count_set(sbi->s_es,
4253                                    EXT4_C2B(sbi, block));
4254         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4255                                   GFP_KERNEL);
4256         if (!err) {
4257                 unsigned long freei = ext4_count_free_inodes(sb);
4258                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4259                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4260                                           GFP_KERNEL);
4261         }
4262         if (!err)
4263                 err = percpu_counter_init(&sbi->s_dirs_counter,
4264                                           ext4_count_dirs(sb), GFP_KERNEL);
4265         if (!err)
4266                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4267                                           GFP_KERNEL);
4268         if (!err)
4269                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4270
4271         if (err) {
4272                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4273                 goto failed_mount6;
4274         }
4275
4276         if (ext4_has_feature_flex_bg(sb))
4277                 if (!ext4_fill_flex_info(sb)) {
4278                         ext4_msg(sb, KERN_ERR,
4279                                "unable to initialize "
4280                                "flex_bg meta info!");
4281                         goto failed_mount6;
4282                 }
4283
4284         err = ext4_register_li_request(sb, first_not_zeroed);
4285         if (err)
4286                 goto failed_mount6;
4287
4288         err = ext4_register_sysfs(sb);
4289         if (err)
4290                 goto failed_mount7;
4291
4292 #ifdef CONFIG_QUOTA
4293         /* Enable quota usage during mount. */
4294         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4295                 err = ext4_enable_quotas(sb);
4296                 if (err)
4297                         goto failed_mount8;
4298         }
4299 #endif  /* CONFIG_QUOTA */
4300
4301         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4302         ext4_orphan_cleanup(sb, es);
4303         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4304         if (needs_recovery) {
4305                 ext4_msg(sb, KERN_INFO, "recovery complete");
4306                 ext4_mark_recovery_complete(sb, es);
4307         }
4308         if (EXT4_SB(sb)->s_journal) {
4309                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4310                         descr = " journalled data mode";
4311                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4312                         descr = " ordered data mode";
4313                 else
4314                         descr = " writeback data mode";
4315         } else
4316                 descr = "out journal";
4317
4318         if (test_opt(sb, DISCARD)) {
4319                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4320                 if (!blk_queue_discard(q))
4321                         ext4_msg(sb, KERN_WARNING,
4322                                  "mounting with \"discard\" option, but "
4323                                  "the device does not support discard");
4324         }
4325
4326         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4327                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4328                          "Opts: %.*s%s%s", descr,
4329                          (int) sizeof(sbi->s_es->s_mount_opts),
4330                          sbi->s_es->s_mount_opts,
4331                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4332
4333         if (es->s_error_count)
4334                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4335
4336         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4337         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4338         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4339         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4340
4341         kfree(orig_data);
4342         return 0;
4343
4344 cantfind_ext4:
4345         if (!silent)
4346                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4347         goto failed_mount;
4348
4349 #ifdef CONFIG_QUOTA
4350 failed_mount8:
4351         ext4_unregister_sysfs(sb);
4352 #endif
4353 failed_mount7:
4354         ext4_unregister_li_request(sb);
4355 failed_mount6:
4356         ext4_mb_release(sb);
4357         if (sbi->s_flex_groups)
4358                 kvfree(sbi->s_flex_groups);
4359         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4360         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4361         percpu_counter_destroy(&sbi->s_dirs_counter);
4362         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4363 failed_mount5:
4364         ext4_ext_release(sb);
4365         ext4_release_system_zone(sb);
4366 failed_mount4a:
4367         dput(sb->s_root);
4368         sb->s_root = NULL;
4369 failed_mount4:
4370         ext4_msg(sb, KERN_ERR, "mount failed");
4371         if (EXT4_SB(sb)->rsv_conversion_wq)
4372                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4373 failed_mount_wq:
4374         if (sbi->s_ea_inode_cache) {
4375                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4376                 sbi->s_ea_inode_cache = NULL;
4377         }
4378         if (sbi->s_ea_block_cache) {
4379                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4380                 sbi->s_ea_block_cache = NULL;
4381         }
4382         if (sbi->s_journal) {
4383                 jbd2_journal_destroy(sbi->s_journal);
4384                 sbi->s_journal = NULL;
4385         }
4386 failed_mount3a:
4387         ext4_es_unregister_shrinker(sbi);
4388 failed_mount3:
4389         del_timer_sync(&sbi->s_err_report);
4390         if (sbi->s_mmp_tsk)
4391                 kthread_stop(sbi->s_mmp_tsk);
4392 failed_mount2:
4393         for (i = 0; i < db_count; i++)
4394                 brelse(sbi->s_group_desc[i]);
4395         kvfree(sbi->s_group_desc);
4396 failed_mount:
4397         if (sbi->s_chksum_driver)
4398                 crypto_free_shash(sbi->s_chksum_driver);
4399 #ifdef CONFIG_QUOTA
4400         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4401                 kfree(sbi->s_qf_names[i]);
4402 #endif
4403         ext4_blkdev_remove(sbi);
4404         brelse(bh);
4405 out_fail:
4406         sb->s_fs_info = NULL;
4407         kfree(sbi->s_blockgroup_lock);
4408 out_free_base:
4409         kfree(sbi);
4410         kfree(orig_data);
4411         fs_put_dax(dax_dev);
4412         return err ? err : ret;
4413 }
4414
4415 /*
4416  * Setup any per-fs journal parameters now.  We'll do this both on
4417  * initial mount, once the journal has been initialised but before we've
4418  * done any recovery; and again on any subsequent remount.
4419  */
4420 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4421 {
4422         struct ext4_sb_info *sbi = EXT4_SB(sb);
4423
4424         journal->j_commit_interval = sbi->s_commit_interval;
4425         journal->j_min_batch_time = sbi->s_min_batch_time;
4426         journal->j_max_batch_time = sbi->s_max_batch_time;
4427
4428         write_lock(&journal->j_state_lock);
4429         if (test_opt(sb, BARRIER))
4430                 journal->j_flags |= JBD2_BARRIER;
4431         else
4432                 journal->j_flags &= ~JBD2_BARRIER;
4433         if (test_opt(sb, DATA_ERR_ABORT))
4434                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4435         else
4436                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4437         write_unlock(&journal->j_state_lock);
4438 }
4439
4440 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4441                                              unsigned int journal_inum)
4442 {
4443         struct inode *journal_inode;
4444
4445         /*
4446          * Test for the existence of a valid inode on disk.  Bad things
4447          * happen if we iget() an unused inode, as the subsequent iput()
4448          * will try to delete it.
4449          */
4450         journal_inode = ext4_iget(sb, journal_inum);
4451         if (IS_ERR(journal_inode)) {
4452                 ext4_msg(sb, KERN_ERR, "no journal found");
4453                 return NULL;
4454         }
4455         if (!journal_inode->i_nlink) {
4456                 make_bad_inode(journal_inode);
4457                 iput(journal_inode);
4458                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4459                 return NULL;
4460         }
4461
4462         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4463                   journal_inode, journal_inode->i_size);
4464         if (!S_ISREG(journal_inode->i_mode)) {
4465                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4466                 iput(journal_inode);
4467                 return NULL;
4468         }
4469         return journal_inode;
4470 }
4471
4472 static journal_t *ext4_get_journal(struct super_block *sb,
4473                                    unsigned int journal_inum)
4474 {
4475         struct inode *journal_inode;
4476         journal_t *journal;
4477
4478         BUG_ON(!ext4_has_feature_journal(sb));
4479
4480         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4481         if (!journal_inode)
4482                 return NULL;
4483
4484         journal = jbd2_journal_init_inode(journal_inode);
4485         if (!journal) {
4486                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4487                 iput(journal_inode);
4488                 return NULL;
4489         }
4490         journal->j_private = sb;
4491         ext4_init_journal_params(sb, journal);
4492         return journal;
4493 }
4494
4495 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4496                                        dev_t j_dev)
4497 {
4498         struct buffer_head *bh;
4499         journal_t *journal;
4500         ext4_fsblk_t start;
4501         ext4_fsblk_t len;
4502         int hblock, blocksize;
4503         ext4_fsblk_t sb_block;
4504         unsigned long offset;
4505         struct ext4_super_block *es;
4506         struct block_device *bdev;
4507
4508         BUG_ON(!ext4_has_feature_journal(sb));
4509
4510         bdev = ext4_blkdev_get(j_dev, sb);
4511         if (bdev == NULL)
4512                 return NULL;
4513
4514         blocksize = sb->s_blocksize;
4515         hblock = bdev_logical_block_size(bdev);
4516         if (blocksize < hblock) {
4517                 ext4_msg(sb, KERN_ERR,
4518                         "blocksize too small for journal device");
4519                 goto out_bdev;
4520         }
4521
4522         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4523         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4524         set_blocksize(bdev, blocksize);
4525         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4526                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4527                        "external journal");
4528                 goto out_bdev;
4529         }
4530
4531         es = (struct ext4_super_block *) (bh->b_data + offset);
4532         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4533             !(le32_to_cpu(es->s_feature_incompat) &
4534               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4535                 ext4_msg(sb, KERN_ERR, "external journal has "
4536                                         "bad superblock");
4537                 brelse(bh);
4538                 goto out_bdev;
4539         }
4540
4541         if ((le32_to_cpu(es->s_feature_ro_compat) &
4542              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4543             es->s_checksum != ext4_superblock_csum(sb, es)) {
4544                 ext4_msg(sb, KERN_ERR, "external journal has "
4545                                        "corrupt superblock");
4546                 brelse(bh);
4547                 goto out_bdev;
4548         }
4549
4550         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4551                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4552                 brelse(bh);
4553                 goto out_bdev;
4554         }
4555
4556         len = ext4_blocks_count(es);
4557         start = sb_block + 1;
4558         brelse(bh);     /* we're done with the superblock */
4559
4560         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4561                                         start, len, blocksize);
4562         if (!journal) {
4563                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4564                 goto out_bdev;
4565         }
4566         journal->j_private = sb;
4567         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4568         wait_on_buffer(journal->j_sb_buffer);
4569         if (!buffer_uptodate(journal->j_sb_buffer)) {
4570                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4571                 goto out_journal;
4572         }
4573         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4574                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4575                                         "user (unsupported) - %d",
4576                         be32_to_cpu(journal->j_superblock->s_nr_users));
4577                 goto out_journal;
4578         }
4579         EXT4_SB(sb)->journal_bdev = bdev;
4580         ext4_init_journal_params(sb, journal);
4581         return journal;
4582
4583 out_journal:
4584         jbd2_journal_destroy(journal);
4585 out_bdev:
4586         ext4_blkdev_put(bdev);
4587         return NULL;
4588 }
4589
4590 static int ext4_load_journal(struct super_block *sb,
4591                              struct ext4_super_block *es,
4592                              unsigned long journal_devnum)
4593 {
4594         journal_t *journal;
4595         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4596         dev_t journal_dev;
4597         int err = 0;
4598         int really_read_only;
4599
4600         BUG_ON(!ext4_has_feature_journal(sb));
4601
4602         if (journal_devnum &&
4603             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4604                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4605                         "numbers have changed");
4606                 journal_dev = new_decode_dev(journal_devnum);
4607         } else
4608                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4609
4610         really_read_only = bdev_read_only(sb->s_bdev);
4611
4612         /*
4613          * Are we loading a blank journal or performing recovery after a
4614          * crash?  For recovery, we need to check in advance whether we
4615          * can get read-write access to the device.
4616          */
4617         if (ext4_has_feature_journal_needs_recovery(sb)) {
4618                 if (sb_rdonly(sb)) {
4619                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4620                                         "required on readonly filesystem");
4621                         if (really_read_only) {
4622                                 ext4_msg(sb, KERN_ERR, "write access "
4623                                         "unavailable, cannot proceed "
4624                                         "(try mounting with noload)");
4625                                 return -EROFS;
4626                         }
4627                         ext4_msg(sb, KERN_INFO, "write access will "
4628                                "be enabled during recovery");
4629                 }
4630         }
4631
4632         if (journal_inum && journal_dev) {
4633                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4634                        "and inode journals!");
4635                 return -EINVAL;
4636         }
4637
4638         if (journal_inum) {
4639                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4640                         return -EINVAL;
4641         } else {
4642                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4643                         return -EINVAL;
4644         }
4645
4646         if (!(journal->j_flags & JBD2_BARRIER))
4647                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4648
4649         if (!ext4_has_feature_journal_needs_recovery(sb))
4650                 err = jbd2_journal_wipe(journal, !really_read_only);
4651         if (!err) {
4652                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4653                 if (save)
4654                         memcpy(save, ((char *) es) +
4655                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4656                 err = jbd2_journal_load(journal);
4657                 if (save)
4658                         memcpy(((char *) es) + EXT4_S_ERR_START,
4659                                save, EXT4_S_ERR_LEN);
4660                 kfree(save);
4661         }
4662
4663         if (err) {
4664                 ext4_msg(sb, KERN_ERR, "error loading journal");
4665                 jbd2_journal_destroy(journal);
4666                 return err;
4667         }
4668
4669         EXT4_SB(sb)->s_journal = journal;
4670         ext4_clear_journal_err(sb, es);
4671
4672         if (!really_read_only && journal_devnum &&
4673             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4674                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4675
4676                 /* Make sure we flush the recovery flag to disk. */
4677                 ext4_commit_super(sb, 1);
4678         }
4679
4680         return 0;
4681 }
4682
4683 static int ext4_commit_super(struct super_block *sb, int sync)
4684 {
4685         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4686         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4687         int error = 0;
4688
4689         if (!sbh || block_device_ejected(sb))
4690                 return error;
4691         /*
4692          * If the file system is mounted read-only, don't update the
4693          * superblock write time.  This avoids updating the superblock
4694          * write time when we are mounting the root file system
4695          * read/only but we need to replay the journal; at that point,
4696          * for people who are east of GMT and who make their clock
4697          * tick in localtime for Windows bug-for-bug compatibility,
4698          * the clock is set in the future, and this will cause e2fsck
4699          * to complain and force a full file system check.
4700          */
4701         if (!(sb->s_flags & SB_RDONLY))
4702                 es->s_wtime = cpu_to_le32(get_seconds());
4703         if (sb->s_bdev->bd_part)
4704                 es->s_kbytes_written =
4705                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4706                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4707                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4708         else
4709                 es->s_kbytes_written =
4710                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4711         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4712                 ext4_free_blocks_count_set(es,
4713                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4714                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4715         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4716                 es->s_free_inodes_count =
4717                         cpu_to_le32(percpu_counter_sum_positive(
4718                                 &EXT4_SB(sb)->s_freeinodes_counter));
4719         BUFFER_TRACE(sbh, "marking dirty");
4720         ext4_superblock_csum_set(sb);
4721         if (sync)
4722                 lock_buffer(sbh);
4723         if (buffer_write_io_error(sbh)) {
4724                 /*
4725                  * Oh, dear.  A previous attempt to write the
4726                  * superblock failed.  This could happen because the
4727                  * USB device was yanked out.  Or it could happen to
4728                  * be a transient write error and maybe the block will
4729                  * be remapped.  Nothing we can do but to retry the
4730                  * write and hope for the best.
4731                  */
4732                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4733                        "superblock detected");
4734                 clear_buffer_write_io_error(sbh);
4735                 set_buffer_uptodate(sbh);
4736         }
4737         mark_buffer_dirty(sbh);
4738         if (sync) {
4739                 unlock_buffer(sbh);
4740                 error = __sync_dirty_buffer(sbh,
4741                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
4742                 if (error)
4743                         return error;
4744
4745                 error = buffer_write_io_error(sbh);
4746                 if (error) {
4747                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4748                                "superblock");
4749                         clear_buffer_write_io_error(sbh);
4750                         set_buffer_uptodate(sbh);
4751                 }
4752         }
4753         return error;
4754 }
4755
4756 /*
4757  * Have we just finished recovery?  If so, and if we are mounting (or
4758  * remounting) the filesystem readonly, then we will end up with a
4759  * consistent fs on disk.  Record that fact.
4760  */
4761 static void ext4_mark_recovery_complete(struct super_block *sb,
4762                                         struct ext4_super_block *es)
4763 {
4764         journal_t *journal = EXT4_SB(sb)->s_journal;
4765
4766         if (!ext4_has_feature_journal(sb)) {
4767                 BUG_ON(journal != NULL);
4768                 return;
4769         }
4770         jbd2_journal_lock_updates(journal);
4771         if (jbd2_journal_flush(journal) < 0)
4772                 goto out;
4773
4774         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
4775                 ext4_clear_feature_journal_needs_recovery(sb);
4776                 ext4_commit_super(sb, 1);
4777         }
4778
4779 out:
4780         jbd2_journal_unlock_updates(journal);
4781 }
4782
4783 /*
4784  * If we are mounting (or read-write remounting) a filesystem whose journal
4785  * has recorded an error from a previous lifetime, move that error to the
4786  * main filesystem now.
4787  */
4788 static void ext4_clear_journal_err(struct super_block *sb,
4789                                    struct ext4_super_block *es)
4790 {
4791         journal_t *journal;
4792         int j_errno;
4793         const char *errstr;
4794
4795         BUG_ON(!ext4_has_feature_journal(sb));
4796
4797         journal = EXT4_SB(sb)->s_journal;
4798
4799         /*
4800          * Now check for any error status which may have been recorded in the
4801          * journal by a prior ext4_error() or ext4_abort()
4802          */
4803
4804         j_errno = jbd2_journal_errno(journal);
4805         if (j_errno) {
4806                 char nbuf[16];
4807
4808                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4809                 ext4_warning(sb, "Filesystem error recorded "
4810                              "from previous mount: %s", errstr);
4811                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4812
4813                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4814                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4815                 ext4_commit_super(sb, 1);
4816
4817                 jbd2_journal_clear_err(journal);
4818                 jbd2_journal_update_sb_errno(journal);
4819         }
4820 }
4821
4822 /*
4823  * Force the running and committing transactions to commit,
4824  * and wait on the commit.
4825  */
4826 int ext4_force_commit(struct super_block *sb)
4827 {
4828         journal_t *journal;
4829
4830         if (sb_rdonly(sb))
4831                 return 0;
4832
4833         journal = EXT4_SB(sb)->s_journal;
4834         return ext4_journal_force_commit(journal);
4835 }
4836
4837 static int ext4_sync_fs(struct super_block *sb, int wait)
4838 {
4839         int ret = 0;
4840         tid_t target;
4841         bool needs_barrier = false;
4842         struct ext4_sb_info *sbi = EXT4_SB(sb);
4843
4844         if (unlikely(ext4_forced_shutdown(sbi)))
4845                 return 0;
4846
4847         trace_ext4_sync_fs(sb, wait);
4848         flush_workqueue(sbi->rsv_conversion_wq);
4849         /*
4850          * Writeback quota in non-journalled quota case - journalled quota has
4851          * no dirty dquots
4852          */
4853         dquot_writeback_dquots(sb, -1);
4854         /*
4855          * Data writeback is possible w/o journal transaction, so barrier must
4856          * being sent at the end of the function. But we can skip it if
4857          * transaction_commit will do it for us.
4858          */
4859         if (sbi->s_journal) {
4860                 target = jbd2_get_latest_transaction(sbi->s_journal);
4861                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4862                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4863                         needs_barrier = true;
4864
4865                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4866                         if (wait)
4867                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4868                                                            target);
4869                 }
4870         } else if (wait && test_opt(sb, BARRIER))
4871                 needs_barrier = true;
4872         if (needs_barrier) {
4873                 int err;
4874                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4875                 if (!ret)
4876                         ret = err;
4877         }
4878
4879         return ret;
4880 }
4881
4882 /*
4883  * LVM calls this function before a (read-only) snapshot is created.  This
4884  * gives us a chance to flush the journal completely and mark the fs clean.
4885  *
4886  * Note that only this function cannot bring a filesystem to be in a clean
4887  * state independently. It relies on upper layer to stop all data & metadata
4888  * modifications.
4889  */
4890 static int ext4_freeze(struct super_block *sb)
4891 {
4892         int error = 0;
4893         journal_t *journal;
4894
4895         if (sb_rdonly(sb))
4896                 return 0;
4897
4898         journal = EXT4_SB(sb)->s_journal;
4899
4900         if (journal) {
4901                 /* Now we set up the journal barrier. */
4902                 jbd2_journal_lock_updates(journal);
4903
4904                 /*
4905                  * Don't clear the needs_recovery flag if we failed to
4906                  * flush the journal.
4907                  */
4908                 error = jbd2_journal_flush(journal);
4909                 if (error < 0)
4910                         goto out;
4911
4912                 /* Journal blocked and flushed, clear needs_recovery flag. */
4913                 ext4_clear_feature_journal_needs_recovery(sb);
4914         }
4915
4916         error = ext4_commit_super(sb, 1);
4917 out:
4918         if (journal)
4919                 /* we rely on upper layer to stop further updates */
4920                 jbd2_journal_unlock_updates(journal);
4921         return error;
4922 }
4923
4924 /*
4925  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4926  * flag here, even though the filesystem is not technically dirty yet.
4927  */
4928 static int ext4_unfreeze(struct super_block *sb)
4929 {
4930         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
4931                 return 0;
4932
4933         if (EXT4_SB(sb)->s_journal) {
4934                 /* Reset the needs_recovery flag before the fs is unlocked. */
4935                 ext4_set_feature_journal_needs_recovery(sb);
4936         }
4937
4938         ext4_commit_super(sb, 1);
4939         return 0;
4940 }
4941
4942 /*
4943  * Structure to save mount options for ext4_remount's benefit
4944  */
4945 struct ext4_mount_options {
4946         unsigned long s_mount_opt;
4947         unsigned long s_mount_opt2;
4948         kuid_t s_resuid;
4949         kgid_t s_resgid;
4950         unsigned long s_commit_interval;
4951         u32 s_min_batch_time, s_max_batch_time;
4952 #ifdef CONFIG_QUOTA
4953         int s_jquota_fmt;
4954         char *s_qf_names[EXT4_MAXQUOTAS];
4955 #endif
4956 };
4957
4958 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4959 {
4960         struct ext4_super_block *es;
4961         struct ext4_sb_info *sbi = EXT4_SB(sb);
4962         unsigned long old_sb_flags;
4963         struct ext4_mount_options old_opts;
4964         int enable_quota = 0;
4965         ext4_group_t g;
4966         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4967         int err = 0;
4968 #ifdef CONFIG_QUOTA
4969         int i, j;
4970 #endif
4971         char *orig_data = kstrdup(data, GFP_KERNEL);
4972
4973         /* Store the original options */
4974         old_sb_flags = sb->s_flags;
4975         old_opts.s_mount_opt = sbi->s_mount_opt;
4976         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4977         old_opts.s_resuid = sbi->s_resuid;
4978         old_opts.s_resgid = sbi->s_resgid;
4979         old_opts.s_commit_interval = sbi->s_commit_interval;
4980         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4981         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4982 #ifdef CONFIG_QUOTA
4983         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4984         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4985                 if (sbi->s_qf_names[i]) {
4986                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4987                                                          GFP_KERNEL);
4988                         if (!old_opts.s_qf_names[i]) {
4989                                 for (j = 0; j < i; j++)
4990                                         kfree(old_opts.s_qf_names[j]);
4991                                 kfree(orig_data);
4992                                 return -ENOMEM;
4993                         }
4994                 } else
4995                         old_opts.s_qf_names[i] = NULL;
4996 #endif
4997         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4998                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4999
5000         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5001                 err = -EINVAL;
5002                 goto restore_opts;
5003         }
5004
5005         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5006             test_opt(sb, JOURNAL_CHECKSUM)) {
5007                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5008                          "during remount not supported; ignoring");
5009                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5010         }
5011
5012         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5013                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5014                         ext4_msg(sb, KERN_ERR, "can't mount with "
5015                                  "both data=journal and delalloc");
5016                         err = -EINVAL;
5017                         goto restore_opts;
5018                 }
5019                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5020                         ext4_msg(sb, KERN_ERR, "can't mount with "
5021                                  "both data=journal and dioread_nolock");
5022                         err = -EINVAL;
5023                         goto restore_opts;
5024                 }
5025                 if (test_opt(sb, DAX)) {
5026                         ext4_msg(sb, KERN_ERR, "can't mount with "
5027                                  "both data=journal and dax");
5028                         err = -EINVAL;
5029                         goto restore_opts;
5030                 }
5031         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5032                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5033                         ext4_msg(sb, KERN_ERR, "can't mount with "
5034                                 "journal_async_commit in data=ordered mode");
5035                         err = -EINVAL;
5036                         goto restore_opts;
5037                 }
5038         }
5039
5040         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5041                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5042                 err = -EINVAL;
5043                 goto restore_opts;
5044         }
5045
5046         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5047                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5048                         "dax flag with busy inodes while remounting");
5049                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5050         }
5051
5052         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5053                 ext4_abort(sb, "Abort forced by user");
5054
5055         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5056                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5057
5058         es = sbi->s_es;
5059
5060         if (sbi->s_journal) {
5061                 ext4_init_journal_params(sb, sbi->s_journal);
5062                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5063         }
5064
5065         if (*flags & SB_LAZYTIME)
5066                 sb->s_flags |= SB_LAZYTIME;
5067
5068         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5069                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5070                         err = -EROFS;
5071                         goto restore_opts;
5072                 }
5073
5074                 if (*flags & SB_RDONLY) {
5075                         err = sync_filesystem(sb);
5076                         if (err < 0)
5077                                 goto restore_opts;
5078                         err = dquot_suspend(sb, -1);
5079                         if (err < 0)
5080                                 goto restore_opts;
5081
5082                         /*
5083                          * First of all, the unconditional stuff we have to do
5084                          * to disable replay of the journal when we next remount
5085                          */
5086                         sb->s_flags |= SB_RDONLY;
5087
5088                         /*
5089                          * OK, test if we are remounting a valid rw partition
5090                          * readonly, and if so set the rdonly flag and then
5091                          * mark the partition as valid again.
5092                          */
5093                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5094                             (sbi->s_mount_state & EXT4_VALID_FS))
5095                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5096
5097                         if (sbi->s_journal)
5098                                 ext4_mark_recovery_complete(sb, es);
5099                 } else {
5100                         /* Make sure we can mount this feature set readwrite */
5101                         if (ext4_has_feature_readonly(sb) ||
5102                             !ext4_feature_set_ok(sb, 0)) {
5103                                 err = -EROFS;
5104                                 goto restore_opts;
5105                         }
5106                         /*
5107                          * Make sure the group descriptor checksums
5108                          * are sane.  If they aren't, refuse to remount r/w.
5109                          */
5110                         for (g = 0; g < sbi->s_groups_count; g++) {
5111                                 struct ext4_group_desc *gdp =
5112                                         ext4_get_group_desc(sb, g, NULL);
5113
5114                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5115                                         ext4_msg(sb, KERN_ERR,
5116                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5117                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5118                                                le16_to_cpu(gdp->bg_checksum));
5119                                         err = -EFSBADCRC;
5120                                         goto restore_opts;
5121                                 }
5122                         }
5123
5124                         /*
5125                          * If we have an unprocessed orphan list hanging
5126                          * around from a previously readonly bdev mount,
5127                          * require a full umount/remount for now.
5128                          */
5129                         if (es->s_last_orphan) {
5130                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5131                                        "remount RDWR because of unprocessed "
5132                                        "orphan inode list.  Please "
5133                                        "umount/remount instead");
5134                                 err = -EINVAL;
5135                                 goto restore_opts;
5136                         }
5137
5138                         /*
5139                          * Mounting a RDONLY partition read-write, so reread
5140                          * and store the current valid flag.  (It may have
5141                          * been changed by e2fsck since we originally mounted
5142                          * the partition.)
5143                          */
5144                         if (sbi->s_journal)
5145                                 ext4_clear_journal_err(sb, es);
5146                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5147                         if (!ext4_setup_super(sb, es, 0))
5148                                 sb->s_flags &= ~SB_RDONLY;
5149                         if (ext4_has_feature_mmp(sb))
5150                                 if (ext4_multi_mount_protect(sb,
5151                                                 le64_to_cpu(es->s_mmp_block))) {
5152                                         err = -EROFS;
5153                                         goto restore_opts;
5154                                 }
5155                         enable_quota = 1;
5156                 }
5157         }
5158
5159         /*
5160          * Reinitialize lazy itable initialization thread based on
5161          * current settings
5162          */
5163         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5164                 ext4_unregister_li_request(sb);
5165         else {
5166                 ext4_group_t first_not_zeroed;
5167                 first_not_zeroed = ext4_has_uninit_itable(sb);
5168                 ext4_register_li_request(sb, first_not_zeroed);
5169         }
5170
5171         ext4_setup_system_zone(sb);
5172         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY))
5173                 ext4_commit_super(sb, 1);
5174
5175 #ifdef CONFIG_QUOTA
5176         /* Release old quota file names */
5177         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5178                 kfree(old_opts.s_qf_names[i]);
5179         if (enable_quota) {
5180                 if (sb_any_quota_suspended(sb))
5181                         dquot_resume(sb, -1);
5182                 else if (ext4_has_feature_quota(sb)) {
5183                         err = ext4_enable_quotas(sb);
5184                         if (err)
5185                                 goto restore_opts;
5186                 }
5187         }
5188 #endif
5189
5190         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5191         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5192         kfree(orig_data);
5193         return 0;
5194
5195 restore_opts:
5196         sb->s_flags = old_sb_flags;
5197         sbi->s_mount_opt = old_opts.s_mount_opt;
5198         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5199         sbi->s_resuid = old_opts.s_resuid;
5200         sbi->s_resgid = old_opts.s_resgid;
5201         sbi->s_commit_interval = old_opts.s_commit_interval;
5202         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5203         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5204 #ifdef CONFIG_QUOTA
5205         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5206         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5207                 kfree(sbi->s_qf_names[i]);
5208                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5209         }
5210 #endif
5211         kfree(orig_data);
5212         return err;
5213 }
5214
5215 #ifdef CONFIG_QUOTA
5216 static int ext4_statfs_project(struct super_block *sb,
5217                                kprojid_t projid, struct kstatfs *buf)
5218 {
5219         struct kqid qid;
5220         struct dquot *dquot;
5221         u64 limit;
5222         u64 curblock;
5223
5224         qid = make_kqid_projid(projid);
5225         dquot = dqget(sb, qid);
5226         if (IS_ERR(dquot))
5227                 return PTR_ERR(dquot);
5228         spin_lock(&dquot->dq_dqb_lock);
5229
5230         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5231                  dquot->dq_dqb.dqb_bsoftlimit :
5232                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5233         if (limit && buf->f_blocks > limit) {
5234                 curblock = dquot->dq_dqb.dqb_curspace >> sb->s_blocksize_bits;
5235                 buf->f_blocks = limit;
5236                 buf->f_bfree = buf->f_bavail =
5237                         (buf->f_blocks > curblock) ?
5238                          (buf->f_blocks - curblock) : 0;
5239         }
5240
5241         limit = dquot->dq_dqb.dqb_isoftlimit ?
5242                 dquot->dq_dqb.dqb_isoftlimit :
5243                 dquot->dq_dqb.dqb_ihardlimit;
5244         if (limit && buf->f_files > limit) {
5245                 buf->f_files = limit;
5246                 buf->f_ffree =
5247                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5248                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5249         }
5250
5251         spin_unlock(&dquot->dq_dqb_lock);
5252         dqput(dquot);
5253         return 0;
5254 }
5255 #endif
5256
5257 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5258 {
5259         struct super_block *sb = dentry->d_sb;
5260         struct ext4_sb_info *sbi = EXT4_SB(sb);
5261         struct ext4_super_block *es = sbi->s_es;
5262         ext4_fsblk_t overhead = 0, resv_blocks;
5263         u64 fsid;
5264         s64 bfree;
5265         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5266
5267         if (!test_opt(sb, MINIX_DF))
5268                 overhead = sbi->s_overhead;
5269
5270         buf->f_type = EXT4_SUPER_MAGIC;
5271         buf->f_bsize = sb->s_blocksize;
5272         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5273         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5274                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5275         /* prevent underflow in case that few free space is available */
5276         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5277         buf->f_bavail = buf->f_bfree -
5278                         (ext4_r_blocks_count(es) + resv_blocks);
5279         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5280                 buf->f_bavail = 0;
5281         buf->f_files = le32_to_cpu(es->s_inodes_count);
5282         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5283         buf->f_namelen = EXT4_NAME_LEN;
5284         fsid = le64_to_cpup((void *)es->s_uuid) ^
5285                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5286         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5287         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5288
5289 #ifdef CONFIG_QUOTA
5290         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5291             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5292                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5293 #endif
5294         return 0;
5295 }
5296
5297
5298 #ifdef CONFIG_QUOTA
5299
5300 /*
5301  * Helper functions so that transaction is started before we acquire dqio_sem
5302  * to keep correct lock ordering of transaction > dqio_sem
5303  */
5304 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5305 {
5306         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5307 }
5308
5309 static int ext4_write_dquot(struct dquot *dquot)
5310 {
5311         int ret, err;
5312         handle_t *handle;
5313         struct inode *inode;
5314
5315         inode = dquot_to_inode(dquot);
5316         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5317                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5318         if (IS_ERR(handle))
5319                 return PTR_ERR(handle);
5320         ret = dquot_commit(dquot);
5321         err = ext4_journal_stop(handle);
5322         if (!ret)
5323                 ret = err;
5324         return ret;
5325 }
5326
5327 static int ext4_acquire_dquot(struct dquot *dquot)
5328 {
5329         int ret, err;
5330         handle_t *handle;
5331
5332         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5333                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5334         if (IS_ERR(handle))
5335                 return PTR_ERR(handle);
5336         ret = dquot_acquire(dquot);
5337         err = ext4_journal_stop(handle);
5338         if (!ret)
5339                 ret = err;
5340         return ret;
5341 }
5342
5343 static int ext4_release_dquot(struct dquot *dquot)
5344 {
5345         int ret, err;
5346         handle_t *handle;
5347
5348         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5349                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5350         if (IS_ERR(handle)) {
5351                 /* Release dquot anyway to avoid endless cycle in dqput() */
5352                 dquot_release(dquot);
5353                 return PTR_ERR(handle);
5354         }
5355         ret = dquot_release(dquot);
5356         err = ext4_journal_stop(handle);
5357         if (!ret)
5358                 ret = err;
5359         return ret;
5360 }
5361
5362 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5363 {
5364         struct super_block *sb = dquot->dq_sb;
5365         struct ext4_sb_info *sbi = EXT4_SB(sb);
5366
5367         /* Are we journaling quotas? */
5368         if (ext4_has_feature_quota(sb) ||
5369             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5370                 dquot_mark_dquot_dirty(dquot);
5371                 return ext4_write_dquot(dquot);
5372         } else {
5373                 return dquot_mark_dquot_dirty(dquot);
5374         }
5375 }
5376
5377 static int ext4_write_info(struct super_block *sb, int type)
5378 {
5379         int ret, err;
5380         handle_t *handle;
5381
5382         /* Data block + inode block */
5383         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5384         if (IS_ERR(handle))
5385                 return PTR_ERR(handle);
5386         ret = dquot_commit_info(sb, type);
5387         err = ext4_journal_stop(handle);
5388         if (!ret)
5389                 ret = err;
5390         return ret;
5391 }
5392
5393 /*
5394  * Turn on quotas during mount time - we need to find
5395  * the quota file and such...
5396  */
5397 static int ext4_quota_on_mount(struct super_block *sb, int type)
5398 {
5399         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5400                                         EXT4_SB(sb)->s_jquota_fmt, type);
5401 }
5402
5403 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5404 {
5405         struct ext4_inode_info *ei = EXT4_I(inode);
5406
5407         /* The first argument of lockdep_set_subclass has to be
5408          * *exactly* the same as the argument to init_rwsem() --- in
5409          * this case, in init_once() --- or lockdep gets unhappy
5410          * because the name of the lock is set using the
5411          * stringification of the argument to init_rwsem().
5412          */
5413         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5414         lockdep_set_subclass(&ei->i_data_sem, subclass);
5415 }
5416
5417 /*
5418  * Standard function to be called on quota_on
5419  */
5420 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5421                          const struct path *path)
5422 {
5423         int err;
5424
5425         if (!test_opt(sb, QUOTA))
5426                 return -EINVAL;
5427
5428         /* Quotafile not on the same filesystem? */
5429         if (path->dentry->d_sb != sb)
5430                 return -EXDEV;
5431         /* Journaling quota? */
5432         if (EXT4_SB(sb)->s_qf_names[type]) {
5433                 /* Quotafile not in fs root? */
5434                 if (path->dentry->d_parent != sb->s_root)
5435                         ext4_msg(sb, KERN_WARNING,
5436                                 "Quota file not on filesystem root. "
5437                                 "Journaled quota will not work");
5438                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5439         } else {
5440                 /*
5441                  * Clear the flag just in case mount options changed since
5442                  * last time.
5443                  */
5444                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5445         }
5446
5447         /*
5448          * When we journal data on quota file, we have to flush journal to see
5449          * all updates to the file when we bypass pagecache...
5450          */
5451         if (EXT4_SB(sb)->s_journal &&
5452             ext4_should_journal_data(d_inode(path->dentry))) {
5453                 /*
5454                  * We don't need to lock updates but journal_flush() could
5455                  * otherwise be livelocked...
5456                  */
5457                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5458                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5459                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5460                 if (err)
5461                         return err;
5462         }
5463
5464         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5465         err = dquot_quota_on(sb, type, format_id, path);
5466         if (err) {
5467                 lockdep_set_quota_inode(path->dentry->d_inode,
5468                                              I_DATA_SEM_NORMAL);
5469         } else {
5470                 struct inode *inode = d_inode(path->dentry);
5471                 handle_t *handle;
5472
5473                 /*
5474                  * Set inode flags to prevent userspace from messing with quota
5475                  * files. If this fails, we return success anyway since quotas
5476                  * are already enabled and this is not a hard failure.
5477                  */
5478                 inode_lock(inode);
5479                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5480                 if (IS_ERR(handle))
5481                         goto unlock_inode;
5482                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5483                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5484                                 S_NOATIME | S_IMMUTABLE);
5485                 ext4_mark_inode_dirty(handle, inode);
5486                 ext4_journal_stop(handle);
5487         unlock_inode:
5488                 inode_unlock(inode);
5489         }
5490         return err;
5491 }
5492
5493 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5494                              unsigned int flags)
5495 {
5496         int err;
5497         struct inode *qf_inode;
5498         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5499                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5500                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5501                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5502         };
5503
5504         BUG_ON(!ext4_has_feature_quota(sb));
5505
5506         if (!qf_inums[type])
5507                 return -EPERM;
5508
5509         qf_inode = ext4_iget(sb, qf_inums[type]);
5510         if (IS_ERR(qf_inode)) {
5511                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5512                 return PTR_ERR(qf_inode);
5513         }
5514
5515         /* Don't account quota for quota files to avoid recursion */
5516         qf_inode->i_flags |= S_NOQUOTA;
5517         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5518         err = dquot_enable(qf_inode, type, format_id, flags);
5519         iput(qf_inode);
5520         if (err)
5521                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5522
5523         return err;
5524 }
5525
5526 /* Enable usage tracking for all quota types. */
5527 static int ext4_enable_quotas(struct super_block *sb)
5528 {
5529         int type, err = 0;
5530         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5531                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5532                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5533                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5534         };
5535         bool quota_mopt[EXT4_MAXQUOTAS] = {
5536                 test_opt(sb, USRQUOTA),
5537                 test_opt(sb, GRPQUOTA),
5538                 test_opt(sb, PRJQUOTA),
5539         };
5540
5541         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5542         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5543                 if (qf_inums[type]) {
5544                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5545                                 DQUOT_USAGE_ENABLED |
5546                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5547                         if (err) {
5548                                 for (type--; type >= 0; type--)
5549                                         dquot_quota_off(sb, type);
5550
5551                                 ext4_warning(sb,
5552                                         "Failed to enable quota tracking "
5553                                         "(type=%d, err=%d). Please run "
5554                                         "e2fsck to fix.", type, err);
5555                                 return err;
5556                         }
5557                 }
5558         }
5559         return 0;
5560 }
5561
5562 static int ext4_quota_off(struct super_block *sb, int type)
5563 {
5564         struct inode *inode = sb_dqopt(sb)->files[type];
5565         handle_t *handle;
5566         int err;
5567
5568         /* Force all delayed allocation blocks to be allocated.
5569          * Caller already holds s_umount sem */
5570         if (test_opt(sb, DELALLOC))
5571                 sync_filesystem(sb);
5572
5573         if (!inode || !igrab(inode))
5574                 goto out;
5575
5576         err = dquot_quota_off(sb, type);
5577         if (err || ext4_has_feature_quota(sb))
5578                 goto out_put;
5579
5580         inode_lock(inode);
5581         /*
5582          * Update modification times of quota files when userspace can
5583          * start looking at them. If we fail, we return success anyway since
5584          * this is not a hard failure and quotas are already disabled.
5585          */
5586         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5587         if (IS_ERR(handle))
5588                 goto out_unlock;
5589         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5590         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5591         inode->i_mtime = inode->i_ctime = current_time(inode);
5592         ext4_mark_inode_dirty(handle, inode);
5593         ext4_journal_stop(handle);
5594 out_unlock:
5595         inode_unlock(inode);
5596 out_put:
5597         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5598         iput(inode);
5599         return err;
5600 out:
5601         return dquot_quota_off(sb, type);
5602 }
5603
5604 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5605  * acquiring the locks... As quota files are never truncated and quota code
5606  * itself serializes the operations (and no one else should touch the files)
5607  * we don't have to be afraid of races */
5608 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5609                                size_t len, loff_t off)
5610 {
5611         struct inode *inode = sb_dqopt(sb)->files[type];
5612         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5613         int offset = off & (sb->s_blocksize - 1);
5614         int tocopy;
5615         size_t toread;
5616         struct buffer_head *bh;
5617         loff_t i_size = i_size_read(inode);
5618
5619         if (off > i_size)
5620                 return 0;
5621         if (off+len > i_size)
5622                 len = i_size-off;
5623         toread = len;
5624         while (toread > 0) {
5625                 tocopy = sb->s_blocksize - offset < toread ?
5626                                 sb->s_blocksize - offset : toread;
5627                 bh = ext4_bread(NULL, inode, blk, 0);
5628                 if (IS_ERR(bh))
5629                         return PTR_ERR(bh);
5630                 if (!bh)        /* A hole? */
5631                         memset(data, 0, tocopy);
5632                 else
5633                         memcpy(data, bh->b_data+offset, tocopy);
5634                 brelse(bh);
5635                 offset = 0;
5636                 toread -= tocopy;
5637                 data += tocopy;
5638                 blk++;
5639         }
5640         return len;
5641 }
5642
5643 /* Write to quotafile (we know the transaction is already started and has
5644  * enough credits) */
5645 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5646                                 const char *data, size_t len, loff_t off)
5647 {
5648         struct inode *inode = sb_dqopt(sb)->files[type];
5649         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5650         int err, offset = off & (sb->s_blocksize - 1);
5651         int retries = 0;
5652         struct buffer_head *bh;
5653         handle_t *handle = journal_current_handle();
5654
5655         if (EXT4_SB(sb)->s_journal && !handle) {
5656                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5657                         " cancelled because transaction is not started",
5658                         (unsigned long long)off, (unsigned long long)len);
5659                 return -EIO;
5660         }
5661         /*
5662          * Since we account only one data block in transaction credits,
5663          * then it is impossible to cross a block boundary.
5664          */
5665         if (sb->s_blocksize - offset < len) {
5666                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5667                         " cancelled because not block aligned",
5668                         (unsigned long long)off, (unsigned long long)len);
5669                 return -EIO;
5670         }
5671
5672         do {
5673                 bh = ext4_bread(handle, inode, blk,
5674                                 EXT4_GET_BLOCKS_CREATE |
5675                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5676         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5677                  ext4_should_retry_alloc(inode->i_sb, &retries));
5678         if (IS_ERR(bh))
5679                 return PTR_ERR(bh);
5680         if (!bh)
5681                 goto out;
5682         BUFFER_TRACE(bh, "get write access");
5683         err = ext4_journal_get_write_access(handle, bh);
5684         if (err) {
5685                 brelse(bh);
5686                 return err;
5687         }
5688         lock_buffer(bh);
5689         memcpy(bh->b_data+offset, data, len);
5690         flush_dcache_page(bh->b_page);
5691         unlock_buffer(bh);
5692         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5693         brelse(bh);
5694 out:
5695         if (inode->i_size < off + len) {
5696                 i_size_write(inode, off + len);
5697                 EXT4_I(inode)->i_disksize = inode->i_size;
5698                 ext4_mark_inode_dirty(handle, inode);
5699         }
5700         return len;
5701 }
5702
5703 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5704 {
5705         const struct quota_format_ops   *ops;
5706
5707         if (!sb_has_quota_loaded(sb, qid->type))
5708                 return -ESRCH;
5709         ops = sb_dqopt(sb)->ops[qid->type];
5710         if (!ops || !ops->get_next_id)
5711                 return -ENOSYS;
5712         return dquot_get_next_id(sb, qid);
5713 }
5714 #endif
5715
5716 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5717                        const char *dev_name, void *data)
5718 {
5719         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5720 }
5721
5722 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5723 static inline void register_as_ext2(void)
5724 {
5725         int err = register_filesystem(&ext2_fs_type);
5726         if (err)
5727                 printk(KERN_WARNING
5728                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5729 }
5730
5731 static inline void unregister_as_ext2(void)
5732 {
5733         unregister_filesystem(&ext2_fs_type);
5734 }
5735
5736 static inline int ext2_feature_set_ok(struct super_block *sb)
5737 {
5738         if (ext4_has_unknown_ext2_incompat_features(sb))
5739                 return 0;
5740         if (sb_rdonly(sb))
5741                 return 1;
5742         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5743                 return 0;
5744         return 1;
5745 }
5746 #else
5747 static inline void register_as_ext2(void) { }
5748 static inline void unregister_as_ext2(void) { }
5749 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5750 #endif
5751
5752 static inline void register_as_ext3(void)
5753 {
5754         int err = register_filesystem(&ext3_fs_type);
5755         if (err)
5756                 printk(KERN_WARNING
5757                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5758 }
5759
5760 static inline void unregister_as_ext3(void)
5761 {
5762         unregister_filesystem(&ext3_fs_type);
5763 }
5764
5765 static inline int ext3_feature_set_ok(struct super_block *sb)
5766 {
5767         if (ext4_has_unknown_ext3_incompat_features(sb))
5768                 return 0;
5769         if (!ext4_has_feature_journal(sb))
5770                 return 0;
5771         if (sb_rdonly(sb))
5772                 return 1;
5773         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5774                 return 0;
5775         return 1;
5776 }
5777
5778 static struct file_system_type ext4_fs_type = {
5779         .owner          = THIS_MODULE,
5780         .name           = "ext4",
5781         .mount          = ext4_mount,
5782         .kill_sb        = kill_block_super,
5783         .fs_flags       = FS_REQUIRES_DEV,
5784 };
5785 MODULE_ALIAS_FS("ext4");
5786
5787 /* Shared across all ext4 file systems */
5788 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5789
5790 static int __init ext4_init_fs(void)
5791 {
5792         int i, err;
5793
5794         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5795         ext4_li_info = NULL;
5796         mutex_init(&ext4_li_mtx);
5797
5798         /* Build-time check for flags consistency */
5799         ext4_check_flag_values();
5800
5801         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
5802                 init_waitqueue_head(&ext4__ioend_wq[i]);
5803
5804         err = ext4_init_es();
5805         if (err)
5806                 return err;
5807
5808         err = ext4_init_pageio();
5809         if (err)
5810                 goto out5;
5811
5812         err = ext4_init_system_zone();
5813         if (err)
5814                 goto out4;
5815
5816         err = ext4_init_sysfs();
5817         if (err)
5818                 goto out3;
5819
5820         err = ext4_init_mballoc();
5821         if (err)
5822                 goto out2;
5823         err = init_inodecache();
5824         if (err)
5825                 goto out1;
5826         register_as_ext3();
5827         register_as_ext2();
5828         err = register_filesystem(&ext4_fs_type);
5829         if (err)
5830                 goto out;
5831
5832         return 0;
5833 out:
5834         unregister_as_ext2();
5835         unregister_as_ext3();
5836         destroy_inodecache();
5837 out1:
5838         ext4_exit_mballoc();
5839 out2:
5840         ext4_exit_sysfs();
5841 out3:
5842         ext4_exit_system_zone();
5843 out4:
5844         ext4_exit_pageio();
5845 out5:
5846         ext4_exit_es();
5847
5848         return err;
5849 }
5850
5851 static void __exit ext4_exit_fs(void)
5852 {
5853         ext4_destroy_lazyinit_thread();
5854         unregister_as_ext2();
5855         unregister_as_ext3();
5856         unregister_filesystem(&ext4_fs_type);
5857         destroy_inodecache();
5858         ext4_exit_mballoc();
5859         ext4_exit_sysfs();
5860         ext4_exit_system_zone();
5861         ext4_exit_pageio();
5862         ext4_exit_es();
5863 }
5864
5865 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5866 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5867 MODULE_LICENSE("GPL");
5868 module_init(ext4_init_fs)
5869 module_exit(ext4_exit_fs)