fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/backing-dev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/ctype.h>
  38 #include <linux/log2.h>
  39 #include <linux/crc16.h>
  40 #include <linux/dax.h>
  41 #include <linux/cleancache.h>
  42 #include <linux/uaccess.h>
  43
  44 #include <linux/kthread.h>
  45 #include <linux/freezer.h>
  46
  47 #include "ext4.h"
  48 #include "ext4_extents.h"       /* Needed for trace points definition */
  49 #include "ext4_jbd2.h"
  50 #include "xattr.h"
  51 #include "acl.h"
  52 #include "mballoc.h"
  53 #include "fsmap.h"
  54
  55 #define CREATE_TRACE_POINTS
  56 #include <trace/events/ext4.h>
  57
  58 static struct ext4_lazy_init *ext4_li_info;
  59 static struct mutex ext4_li_mtx;
  60 static struct ratelimit_state ext4_mount_msg_ratelimit;
  61
  62 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  63                              unsigned long journal_devnum);
  64 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  65 static int ext4_commit_super(struct super_block *sb, int sync);
  66 static void ext4_mark_recovery_complete(struct super_block *sb,
  67                                         struct ext4_super_block *es);
  68 static void ext4_clear_journal_err(struct super_block *sb,
  69                                    struct ext4_super_block *es);
  70 static int ext4_sync_fs(struct super_block *sb, int wait);
  71 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  72 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  73 static int ext4_unfreeze(struct super_block *sb);
  74 static int ext4_freeze(struct super_block *sb);
  75 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  76                        const char *dev_name, void *data);
  77 static inline int ext2_feature_set_ok(struct super_block *sb);
  78 static inline int ext3_feature_set_ok(struct super_block *sb);
  79 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  80 static void ext4_destroy_lazyinit_thread(void);
  81 static void ext4_unregister_li_request(struct super_block *sb);
  82 static void ext4_clear_request_list(void);
  83 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  84                                             unsigned int journal_inum);
  85
  86 /*
  87  * Lock ordering
  88  *
  89  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  90  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  91  *
  92  * page fault path:
  93  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  94  *   page lock -> i_data_sem (rw)
  95  *
  96  * buffered write path:
  97  * sb_start_write -> i_mutex -> mmap_sem
  98  * sb_start_write -> i_mutex -> transaction start -> page lock ->
  99  *   i_data_sem (rw)
 100  *
 101  * truncate:
 102  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 103  *   i_mmap_rwsem (w) -> page lock
 104  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 105  *   transaction start -> i_data_sem (rw)
 106  *
 107  * direct IO:
 108  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> mmap_sem
 109  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) ->
 110  *   transaction start -> i_data_sem (rw)
 111  *
 112  * writepages:
 113  * transaction start -> page lock(s) -> i_data_sem (rw)
 114  */
 115
 116 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 117 static struct file_system_type ext2_fs_type = {
 118         .owner          = THIS_MODULE,
 119         .name           = "ext2",
 120         .mount          = ext4_mount,
 121         .kill_sb        = kill_block_super,
 122         .fs_flags       = FS_REQUIRES_DEV,
 123 };
 124 MODULE_ALIAS_FS("ext2");
 125 MODULE_ALIAS("ext2");
 126 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 127 #else
 128 #define IS_EXT2_SB(sb) (0)
 129 #endif
 130
 131
 132 static struct file_system_type ext3_fs_type = {
 133         .owner          = THIS_MODULE,
 134         .name           = "ext3",
 135         .mount          = ext4_mount,
 136         .kill_sb        = kill_block_super,
 137         .fs_flags       = FS_REQUIRES_DEV,
 138 };
 139 MODULE_ALIAS_FS("ext3");
 140 MODULE_ALIAS("ext3");
 141 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 142
 143 static int ext4_verify_csum_type(struct super_block *sb,
 144                                  struct ext4_super_block *es)
 145 {
 146         if (!ext4_has_feature_metadata_csum(sb))
 147                 return 1;
 148
 149         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 150 }
 151
 152 static __le32 ext4_superblock_csum(struct super_block *sb,
 153                                    struct ext4_super_block *es)
 154 {
 155         struct ext4_sb_info *sbi = EXT4_SB(sb);
 156         int offset = offsetof(struct ext4_super_block, s_checksum);
 157         __u32 csum;
 158
 159         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 160
 161         return cpu_to_le32(csum);
 162 }
 163
 164 static int ext4_superblock_csum_verify(struct super_block *sb,
 165                                        struct ext4_super_block *es)
 166 {
 167         if (!ext4_has_metadata_csum(sb))
 168                 return 1;
 169
 170         return es->s_checksum == ext4_superblock_csum(sb, es);
 171 }
 172
 173 void ext4_superblock_csum_set(struct super_block *sb)
 174 {
 175         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 176
 177         if (!ext4_has_metadata_csum(sb))
 178                 return;
 179
 180         es->s_checksum = ext4_superblock_csum(sb, es);
 181 }
 182
 183 void *ext4_kvmalloc(size_t size, gfp_t flags)
 184 {
 185         void *ret;
 186
 187         ret = kmalloc(size, flags | __GFP_NOWARN);
 188         if (!ret)
 189                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 190         return ret;
 191 }
 192
 193 void *ext4_kvzalloc(size_t size, gfp_t flags)
 194 {
 195         void *ret;
 196
 197         ret = kzalloc(size, flags | __GFP_NOWARN);
 198         if (!ret)
 199                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 200         return ret;
 201 }
 202
 203 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 204                                struct ext4_group_desc *bg)
 205 {
 206         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 207                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 208                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 209 }
 210
 211 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 212                                struct ext4_group_desc *bg)
 213 {
 214         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 215                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 216                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 217 }
 218
 219 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 220                               struct ext4_group_desc *bg)
 221 {
 222         return le32_to_cpu(bg->bg_inode_table_lo) |
 223                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 224                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 225 }
 226
 227 __u32 ext4_free_group_clusters(struct super_block *sb,
 228                                struct ext4_group_desc *bg)
 229 {
 230         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 231                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 232                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 233 }
 234
 235 __u32 ext4_free_inodes_count(struct super_block *sb,
 236                               struct ext4_group_desc *bg)
 237 {
 238         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 239                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 240                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 241 }
 242
 243 __u32 ext4_used_dirs_count(struct super_block *sb,
 244                               struct ext4_group_desc *bg)
 245 {
 246         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 247                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 248                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 249 }
 250
 251 __u32 ext4_itable_unused_count(struct super_block *sb,
 252                               struct ext4_group_desc *bg)
 253 {
 254         return le16_to_cpu(bg->bg_itable_unused_lo) |
 255                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 256                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 257 }
 258
 259 void ext4_block_bitmap_set(struct super_block *sb,
 260                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 261 {
 262         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 263         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 264                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 265 }
 266
 267 void ext4_inode_bitmap_set(struct super_block *sb,
 268                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 269 {
 270         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 271         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 272                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 273 }
 274
 275 void ext4_inode_table_set(struct super_block *sb,
 276                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 277 {
 278         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 279         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 280                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 281 }
 282
 283 void ext4_free_group_clusters_set(struct super_block *sb,
 284                                   struct ext4_group_desc *bg, __u32 count)
 285 {
 286         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 287         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 288                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 289 }
 290
 291 void ext4_free_inodes_set(struct super_block *sb,
 292                           struct ext4_group_desc *bg, __u32 count)
 293 {
 294         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 295         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 296                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 297 }
 298
 299 void ext4_used_dirs_set(struct super_block *sb,
 300                           struct ext4_group_desc *bg, __u32 count)
 301 {
 302         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 303         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 304                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 305 }
 306
 307 void ext4_itable_unused_set(struct super_block *sb,
 308                           struct ext4_group_desc *bg, __u32 count)
 309 {
 310         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 311         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 312                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 313 }
 314
 315
 316 static void __save_error_info(struct super_block *sb, const char *func,
 317                             unsigned int line)
 318 {
 319         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 320
 321         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 322         if (bdev_read_only(sb->s_bdev))
 323                 return;
 324         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 325         es->s_last_error_time = cpu_to_le32(get_seconds());
 326         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 327         es->s_last_error_line = cpu_to_le32(line);
 328         if (!es->s_first_error_time) {
 329                 es->s_first_error_time = es->s_last_error_time;
 330                 strncpy(es->s_first_error_func, func,
 331                         sizeof(es->s_first_error_func));
 332                 es->s_first_error_line = cpu_to_le32(line);
 333                 es->s_first_error_ino = es->s_last_error_ino;
 334                 es->s_first_error_block = es->s_last_error_block;
 335         }
 336         /*
 337          * Start the daily error reporting function if it hasn't been
 338          * started already
 339          */
 340         if (!es->s_error_count)
 341                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 342         le32_add_cpu(&es->s_error_count, 1);
 343 }
 344
 345 static void save_error_info(struct super_block *sb, const char *func,
 346                             unsigned int line)
 347 {
 348         __save_error_info(sb, func, line);
 349         ext4_commit_super(sb, 1);
 350 }
 351
 352 /*
 353  * The del_gendisk() function uninitializes the disk-specific data
 354  * structures, including the bdi structure, without telling anyone
 355  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 356  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 357  * This is a kludge to prevent these oops until we can put in a proper
 358  * hook in del_gendisk() to inform the VFS and file system layers.
 359  */
 360 static int block_device_ejected(struct super_block *sb)
 361 {
 362         struct inode *bd_inode = sb->s_bdev->bd_inode;
 363         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 364
 365         return bdi->dev == NULL;
 366 }
 367
 368 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 369 {
 370         struct super_block              *sb = journal->j_private;
 371         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 372         int                             error = is_journal_aborted(journal);
 373         struct ext4_journal_cb_entry    *jce;
 374
 375         BUG_ON(txn->t_state == T_FINISHED);
 376
 377         ext4_process_freed_data(sb, txn->t_tid);
 378
 379         spin_lock(&sbi->s_md_lock);
 380         while (!list_empty(&txn->t_private_list)) {
 381                 jce = list_entry(txn->t_private_list.next,
 382                                  struct ext4_journal_cb_entry, jce_list);
 383                 list_del_init(&jce->jce_list);
 384                 spin_unlock(&sbi->s_md_lock);
 385                 jce->jce_func(sb, jce, error);
 386                 spin_lock(&sbi->s_md_lock);
 387         }
 388         spin_unlock(&sbi->s_md_lock);
 389 }
 390
 391 /* Deal with the reporting of failure conditions on a filesystem such as
 392  * inconsistencies detected or read IO failures.
 393  *
 394  * On ext2, we can store the error state of the filesystem in the
 395  * superblock.  That is not possible on ext4, because we may have other
 396  * write ordering constraints on the superblock which prevent us from
 397  * writing it out straight away; and given that the journal is about to
 398  * be aborted, we can't rely on the current, or future, transactions to
 399  * write out the superblock safely.
 400  *
 401  * We'll just use the jbd2_journal_abort() error code to record an error in
 402  * the journal instead.  On recovery, the journal will complain about
 403  * that error until we've noted it down and cleared it.
 404  */
 405
 406 static void ext4_handle_error(struct super_block *sb)
 407 {
 408         if (sb->s_flags & MS_RDONLY)
 409                 return;
 410
 411         if (!test_opt(sb, ERRORS_CONT)) {
 412                 journal_t *journal = EXT4_SB(sb)->s_journal;
 413
 414                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 415                 if (journal)
 416                         jbd2_journal_abort(journal, -EIO);
 417         }
 418         if (test_opt(sb, ERRORS_RO)) {
 419                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 420                 /*
 421                  * Make sure updated value of ->s_mount_flags will be visible
 422                  * before ->s_flags update
 423                  */
 424                 smp_wmb();
 425                 sb->s_flags |= MS_RDONLY;
 426         }
 427         if (test_opt(sb, ERRORS_PANIC)) {
 428                 if (EXT4_SB(sb)->s_journal &&
 429                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 430                         return;
 431                 panic("EXT4-fs (device %s): panic forced after error\n",
 432                         sb->s_id);
 433         }
 434 }
 435
 436 #define ext4_error_ratelimit(sb)                                        \
 437                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 438                              "EXT4-fs error")
 439
 440 void __ext4_error(struct super_block *sb, const char *function,
 441                   unsigned int line, const char *fmt, ...)
 442 {
 443         struct va_format vaf;
 444         va_list args;
 445
 446         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 447                 return;
 448
 449         if (ext4_error_ratelimit(sb)) {
 450                 va_start(args, fmt);
 451                 vaf.fmt = fmt;
 452                 vaf.va = &args;
 453                 printk(KERN_CRIT
 454                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 455                        sb->s_id, function, line, current->comm, &vaf);
 456                 va_end(args);
 457         }
 458         save_error_info(sb, function, line);
 459         ext4_handle_error(sb);
 460 }
 461
 462 void __ext4_error_inode(struct inode *inode, const char *function,
 463                         unsigned int line, ext4_fsblk_t block,
 464                         const char *fmt, ...)
 465 {
 466         va_list args;
 467         struct va_format vaf;
 468         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 469
 470         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 471                 return;
 472
 473         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 474         es->s_last_error_block = cpu_to_le64(block);
 475         if (ext4_error_ratelimit(inode->i_sb)) {
 476                 va_start(args, fmt);
 477                 vaf.fmt = fmt;
 478                 vaf.va = &args;
 479                 if (block)
 480                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 481                                "inode #%lu: block %llu: comm %s: %pV\n",
 482                                inode->i_sb->s_id, function, line, inode->i_ino,
 483                                block, current->comm, &vaf);
 484                 else
 485                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 486                                "inode #%lu: comm %s: %pV\n",
 487                                inode->i_sb->s_id, function, line, inode->i_ino,
 488                                current->comm, &vaf);
 489                 va_end(args);
 490         }
 491         save_error_info(inode->i_sb, function, line);
 492         ext4_handle_error(inode->i_sb);
 493 }
 494
 495 void __ext4_error_file(struct file *file, const char *function,
 496                        unsigned int line, ext4_fsblk_t block,
 497                        const char *fmt, ...)
 498 {
 499         va_list args;
 500         struct va_format vaf;
 501         struct ext4_super_block *es;
 502         struct inode *inode = file_inode(file);
 503         char pathname[80], *path;
 504
 505         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
 506                 return;
 507
 508         es = EXT4_SB(inode->i_sb)->s_es;
 509         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 510         if (ext4_error_ratelimit(inode->i_sb)) {
 511                 path = file_path(file, pathname, sizeof(pathname));
 512                 if (IS_ERR(path))
 513                         path = "(unknown)";
 514                 va_start(args, fmt);
 515                 vaf.fmt = fmt;
 516                 vaf.va = &args;
 517                 if (block)
 518                         printk(KERN_CRIT
 519                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 520                                "block %llu: comm %s: path %s: %pV\n",
 521                                inode->i_sb->s_id, function, line, inode->i_ino,
 522                                block, current->comm, path, &vaf);
 523                 else
 524                         printk(KERN_CRIT
 525                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 526                                "comm %s: path %s: %pV\n",
 527                                inode->i_sb->s_id, function, line, inode->i_ino,
 528                                current->comm, path, &vaf);
 529                 va_end(args);
 530         }
 531         save_error_info(inode->i_sb, function, line);
 532         ext4_handle_error(inode->i_sb);
 533 }
 534
 535 const char *ext4_decode_error(struct super_block *sb, int errno,
 536                               char nbuf[16])
 537 {
 538         char *errstr = NULL;
 539
 540         switch (errno) {
 541         case -EFSCORRUPTED:
 542                 errstr = "Corrupt filesystem";
 543                 break;
 544         case -EFSBADCRC:
 545                 errstr = "Filesystem failed CRC";
 546                 break;
 547         case -EIO:
 548                 errstr = "IO failure";
 549                 break;
 550         case -ENOMEM:
 551                 errstr = "Out of memory";
 552                 break;
 553         case -EROFS:
 554                 if (!sb || (EXT4_SB(sb)->s_journal &&
 555                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 556                         errstr = "Journal has aborted";
 557                 else
 558                         errstr = "Readonly filesystem";
 559                 break;
 560         default:
 561                 /* If the caller passed in an extra buffer for unknown
 562                  * errors, textualise them now.  Else we just return
 563                  * NULL. */
 564                 if (nbuf) {
 565                         /* Check for truncated error codes... */
 566                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 567                                 errstr = nbuf;
 568                 }
 569                 break;
 570         }
 571
 572         return errstr;
 573 }
 574
 575 /* __ext4_std_error decodes expected errors from journaling functions
 576  * automatically and invokes the appropriate error response.  */
 577
 578 void __ext4_std_error(struct super_block *sb, const char *function,
 579                       unsigned int line, int errno)
 580 {
 581         char nbuf[16];
 582         const char *errstr;
 583
 584         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 585                 return;
 586
 587         /* Special case: if the error is EROFS, and we're not already
 588          * inside a transaction, then there's really no point in logging
 589          * an error. */
 590         if (errno == -EROFS && journal_current_handle() == NULL &&
 591             (sb->s_flags & MS_RDONLY))
 592                 return;
 593
 594         if (ext4_error_ratelimit(sb)) {
 595                 errstr = ext4_decode_error(sb, errno, nbuf);
 596                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 597                        sb->s_id, function, line, errstr);
 598         }
 599
 600         save_error_info(sb, function, line);
 601         ext4_handle_error(sb);
 602 }
 603
 604 /*
 605  * ext4_abort is a much stronger failure handler than ext4_error.  The
 606  * abort function may be used to deal with unrecoverable failures such
 607  * as journal IO errors or ENOMEM at a critical moment in log management.
 608  *
 609  * We unconditionally force the filesystem into an ABORT|READONLY state,
 610  * unless the error response on the fs has been set to panic in which
 611  * case we take the easy way out and panic immediately.
 612  */
 613
 614 void __ext4_abort(struct super_block *sb, const char *function,
 615                 unsigned int line, const char *fmt, ...)
 616 {
 617         struct va_format vaf;
 618         va_list args;
 619
 620         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 621                 return;
 622
 623         save_error_info(sb, function, line);
 624         va_start(args, fmt);
 625         vaf.fmt = fmt;
 626         vaf.va = &args;
 627         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 628                sb->s_id, function, line, &vaf);
 629         va_end(args);
 630
 631         if ((sb->s_flags & MS_RDONLY) == 0) {
 632                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 633                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 634                 /*
 635                  * Make sure updated value of ->s_mount_flags will be visible
 636                  * before ->s_flags update
 637                  */
 638                 smp_wmb();
 639                 sb->s_flags |= MS_RDONLY;
 640                 if (EXT4_SB(sb)->s_journal)
 641                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 642                 save_error_info(sb, function, line);
 643         }
 644         if (test_opt(sb, ERRORS_PANIC)) {
 645                 if (EXT4_SB(sb)->s_journal &&
 646                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 647                         return;
 648                 panic("EXT4-fs panic from previous error\n");
 649         }
 650 }
 651
 652 void __ext4_msg(struct super_block *sb,
 653                 const char *prefix, const char *fmt, ...)
 654 {
 655         struct va_format vaf;
 656         va_list args;
 657
 658         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 659                 return;
 660
 661         va_start(args, fmt);
 662         vaf.fmt = fmt;
 663         vaf.va = &args;
 664         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 665         va_end(args);
 666 }
 667
 668 #define ext4_warning_ratelimit(sb)                                      \
 669                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 670                              "EXT4-fs warning")
 671
 672 void __ext4_warning(struct super_block *sb, const char *function,
 673                     unsigned int line, const char *fmt, ...)
 674 {
 675         struct va_format vaf;
 676         va_list args;
 677
 678         if (!ext4_warning_ratelimit(sb))
 679                 return;
 680
 681         va_start(args, fmt);
 682         vaf.fmt = fmt;
 683         vaf.va = &args;
 684         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 685                sb->s_id, function, line, &vaf);
 686         va_end(args);
 687 }
 688
 689 void __ext4_warning_inode(const struct inode *inode, const char *function,
 690                           unsigned int line, const char *fmt, ...)
 691 {
 692         struct va_format vaf;
 693         va_list args;
 694
 695         if (!ext4_warning_ratelimit(inode->i_sb))
 696                 return;
 697
 698         va_start(args, fmt);
 699         vaf.fmt = fmt;
 700         vaf.va = &args;
 701         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 702                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 703                function, line, inode->i_ino, current->comm, &vaf);
 704         va_end(args);
 705 }
 706
 707 void __ext4_grp_locked_error(const char *function, unsigned int line,
 708                              struct super_block *sb, ext4_group_t grp,
 709                              unsigned long ino, ext4_fsblk_t block,
 710                              const char *fmt, ...)
 711 __releases(bitlock)
 712 __acquires(bitlock)
 713 {
 714         struct va_format vaf;
 715         va_list args;
 716         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 717
 718         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
 719                 return;
 720
 721         es->s_last_error_ino = cpu_to_le32(ino);
 722         es->s_last_error_block = cpu_to_le64(block);
 723         __save_error_info(sb, function, line);
 724
 725         if (ext4_error_ratelimit(sb)) {
 726                 va_start(args, fmt);
 727                 vaf.fmt = fmt;
 728                 vaf.va = &args;
 729                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 730                        sb->s_id, function, line, grp);
 731                 if (ino)
 732                         printk(KERN_CONT "inode %lu: ", ino);
 733                 if (block)
 734                         printk(KERN_CONT "block %llu:",
 735                                (unsigned long long) block);
 736                 printk(KERN_CONT "%pV\n", &vaf);
 737                 va_end(args);
 738         }
 739
 740         if (test_opt(sb, ERRORS_CONT)) {
 741                 ext4_commit_super(sb, 0);
 742                 return;
 743         }
 744
 745         ext4_unlock_group(sb, grp);
 746         ext4_handle_error(sb);
 747         /*
 748          * We only get here in the ERRORS_RO case; relocking the group
 749          * may be dangerous, but nothing bad will happen since the
 750          * filesystem will have already been marked read/only and the
 751          * journal has been aborted.  We return 1 as a hint to callers
 752          * who might what to use the return value from
 753          * ext4_grp_locked_error() to distinguish between the
 754          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 755          * aggressively from the ext4 function in question, with a
 756          * more appropriate error code.
 757          */
 758         ext4_lock_group(sb, grp);
 759         return;
 760 }
 761
 762 void ext4_update_dynamic_rev(struct super_block *sb)
 763 {
 764         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 765
 766         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 767                 return;
 768
 769         ext4_warning(sb,
 770                      "updating to rev %d because of new feature flag, "
 771                      "running e2fsck is recommended",
 772                      EXT4_DYNAMIC_REV);
 773
 774         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 775         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 776         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 777         /* leave es->s_feature_*compat flags alone */
 778         /* es->s_uuid will be set by e2fsck if empty */
 779
 780         /*
 781          * The rest of the superblock fields should be zero, and if not it
 782          * means they are likely already in use, so leave them alone.  We
 783          * can leave it up to e2fsck to clean up any inconsistencies there.
 784          */
 785 }
 786
 787 /*
 788  * Open the external journal device
 789  */
 790 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 791 {
 792         struct block_device *bdev;
 793         char b[BDEVNAME_SIZE];
 794
 795         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 796         if (IS_ERR(bdev))
 797                 goto fail;
 798         return bdev;
 799
 800 fail:
 801         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 802                         __bdevname(dev, b), PTR_ERR(bdev));
 803         return NULL;
 804 }
 805
 806 /*
 807  * Release the journal device
 808  */
 809 static void ext4_blkdev_put(struct block_device *bdev)
 810 {
 811         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 812 }
 813
 814 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 815 {
 816         struct block_device *bdev;
 817         bdev = sbi->journal_bdev;
 818         if (bdev) {
 819                 ext4_blkdev_put(bdev);
 820                 sbi->journal_bdev = NULL;
 821         }
 822 }
 823
 824 static inline struct inode *orphan_list_entry(struct list_head *l)
 825 {
 826         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 827 }
 828
 829 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 830 {
 831         struct list_head *l;
 832
 833         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 834                  le32_to_cpu(sbi->s_es->s_last_orphan));
 835
 836         printk(KERN_ERR "sb_info orphan list:\n");
 837         list_for_each(l, &sbi->s_orphan) {
 838                 struct inode *inode = orphan_list_entry(l);
 839                 printk(KERN_ERR "  "
 840                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 841                        inode->i_sb->s_id, inode->i_ino, inode,
 842                        inode->i_mode, inode->i_nlink,
 843                        NEXT_ORPHAN(inode));
 844         }
 845 }
 846
 847 #ifdef CONFIG_QUOTA
 848 static int ext4_quota_off(struct super_block *sb, int type);
 849
 850 static inline void ext4_quota_off_umount(struct super_block *sb)
 851 {
 852         int type;
 853
 854         /* Use our quota_off function to clear inode flags etc. */
 855         for (type = 0; type < EXT4_MAXQUOTAS; type++)
 856                 ext4_quota_off(sb, type);
 857 }
 858 #else
 859 static inline void ext4_quota_off_umount(struct super_block *sb)
 860 {
 861 }
 862 #endif
 863
 864 static void ext4_put_super(struct super_block *sb)
 865 {
 866         struct ext4_sb_info *sbi = EXT4_SB(sb);
 867         struct ext4_super_block *es = sbi->s_es;
 868         int aborted = 0;
 869         int i, err;
 870
 871         ext4_unregister_li_request(sb);
 872         ext4_quota_off_umount(sb);
 873
 874         flush_workqueue(sbi->rsv_conversion_wq);
 875         destroy_workqueue(sbi->rsv_conversion_wq);
 876
 877         if (sbi->s_journal) {
 878                 aborted = is_journal_aborted(sbi->s_journal);
 879                 err = jbd2_journal_destroy(sbi->s_journal);
 880                 sbi->s_journal = NULL;
 881                 if ((err < 0) && !aborted)
 882                         ext4_abort(sb, "Couldn't clean up the journal");
 883         }
 884
 885         ext4_unregister_sysfs(sb);
 886         ext4_es_unregister_shrinker(sbi);
 887         del_timer_sync(&sbi->s_err_report);
 888         ext4_release_system_zone(sb);
 889         ext4_mb_release(sb);
 890         ext4_ext_release(sb);
 891
 892         if (!(sb->s_flags & MS_RDONLY) && !aborted) {
 893                 ext4_clear_feature_journal_needs_recovery(sb);
 894                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 895         }
 896         if (!(sb->s_flags & MS_RDONLY))
 897                 ext4_commit_super(sb, 1);
 898
 899         for (i = 0; i < sbi->s_gdb_count; i++)
 900                 brelse(sbi->s_group_desc[i]);
 901         kvfree(sbi->s_group_desc);
 902         kvfree(sbi->s_flex_groups);
 903         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 904         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 905         percpu_counter_destroy(&sbi->s_dirs_counter);
 906         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 907         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
 908 #ifdef CONFIG_QUOTA
 909         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 910                 kfree(sbi->s_qf_names[i]);
 911 #endif
 912
 913         /* Debugging code just in case the in-memory inode orphan list
 914          * isn't empty.  The on-disk one can be non-empty if we've
 915          * detected an error and taken the fs readonly, but the
 916          * in-memory list had better be clean by this point. */
 917         if (!list_empty(&sbi->s_orphan))
 918                 dump_orphan_list(sb, sbi);
 919         J_ASSERT(list_empty(&sbi->s_orphan));
 920
 921         sync_blockdev(sb->s_bdev);
 922         invalidate_bdev(sb->s_bdev);
 923         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 924                 /*
 925                  * Invalidate the journal device's buffers.  We don't want them
 926                  * floating about in memory - the physical journal device may
 927                  * hotswapped, and it breaks the `ro-after' testing code.
 928                  */
 929                 sync_blockdev(sbi->journal_bdev);
 930                 invalidate_bdev(sbi->journal_bdev);
 931                 ext4_blkdev_remove(sbi);
 932         }
 933         if (sbi->s_ea_inode_cache) {
 934                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
 935                 sbi->s_ea_inode_cache = NULL;
 936         }
 937         if (sbi->s_ea_block_cache) {
 938                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
 939                 sbi->s_ea_block_cache = NULL;
 940         }
 941         if (sbi->s_mmp_tsk)
 942                 kthread_stop(sbi->s_mmp_tsk);
 943         brelse(sbi->s_sbh);
 944         sb->s_fs_info = NULL;
 945         /*
 946          * Now that we are completely done shutting down the
 947          * superblock, we need to actually destroy the kobject.
 948          */
 949         kobject_put(&sbi->s_kobj);
 950         wait_for_completion(&sbi->s_kobj_unregister);
 951         if (sbi->s_chksum_driver)
 952                 crypto_free_shash(sbi->s_chksum_driver);
 953         kfree(sbi->s_blockgroup_lock);
 954         fs_put_dax(sbi->s_daxdev);
 955         kfree(sbi);
 956 }
 957
 958 static struct kmem_cache *ext4_inode_cachep;
 959
 960 /*
 961  * Called inside transaction, so use GFP_NOFS
 962  */
 963 static struct inode *ext4_alloc_inode(struct super_block *sb)
 964 {
 965         struct ext4_inode_info *ei;
 966
 967         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 968         if (!ei)
 969                 return NULL;
 970
 971         ei->vfs_inode.i_version = 1;
 972         spin_lock_init(&ei->i_raw_lock);
 973         INIT_LIST_HEAD(&ei->i_prealloc_list);
 974         spin_lock_init(&ei->i_prealloc_lock);
 975         ext4_es_init_tree(&ei->i_es_tree);
 976         rwlock_init(&ei->i_es_lock);
 977         INIT_LIST_HEAD(&ei->i_es_list);
 978         ei->i_es_all_nr = 0;
 979         ei->i_es_shk_nr = 0;
 980         ei->i_es_shrink_lblk = 0;
 981         ei->i_reserved_data_blocks = 0;
 982         ei->i_da_metadata_calc_len = 0;
 983         ei->i_da_metadata_calc_last_lblock = 0;
 984         spin_lock_init(&(ei->i_block_reservation_lock));
 985 #ifdef CONFIG_QUOTA
 986         ei->i_reserved_quota = 0;
 987         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 988 #endif
 989         ei->jinode = NULL;
 990         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 991         spin_lock_init(&ei->i_completed_io_lock);
 992         ei->i_sync_tid = 0;
 993         ei->i_datasync_tid = 0;
 994         atomic_set(&ei->i_unwritten, 0);
 995         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 996         return &ei->vfs_inode;
 997 }
 998
 999 static int ext4_drop_inode(struct inode *inode)
1000 {
1001         int drop = generic_drop_inode(inode);
1002
1003         trace_ext4_drop_inode(inode, drop);
1004         return drop;
1005 }
1006
1007 static void ext4_i_callback(struct rcu_head *head)
1008 {
1009         struct inode *inode = container_of(head, struct inode, i_rcu);
1010         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1011 }
1012
1013 static void ext4_destroy_inode(struct inode *inode)
1014 {
1015         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1016                 ext4_msg(inode->i_sb, KERN_ERR,
1017                          "Inode %lu (%p): orphan list check failed!",
1018                          inode->i_ino, EXT4_I(inode));
1019                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1020                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1021                                 true);
1022                 dump_stack();
1023         }
1024         call_rcu(&inode->i_rcu, ext4_i_callback);
1025 }
1026
1027 static void init_once(void *foo)
1028 {
1029         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1030
1031         INIT_LIST_HEAD(&ei->i_orphan);
1032         init_rwsem(&ei->xattr_sem);
1033         init_rwsem(&ei->i_data_sem);
1034         init_rwsem(&ei->i_mmap_sem);
1035         inode_init_once(&ei->vfs_inode);
1036 }
1037
1038 static int __init init_inodecache(void)
1039 {
1040         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1041                                              sizeof(struct ext4_inode_info),
1042                                              0, (SLAB_RECLAIM_ACCOUNT|
1043                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
1044                                              init_once);
1045         if (ext4_inode_cachep == NULL)
1046                 return -ENOMEM;
1047         return 0;
1048 }
1049
1050 static void destroy_inodecache(void)
1051 {
1052         /*
1053          * Make sure all delayed rcu free inodes are flushed before we
1054          * destroy cache.
1055          */
1056         rcu_barrier();
1057         kmem_cache_destroy(ext4_inode_cachep);
1058 }
1059
1060 void ext4_clear_inode(struct inode *inode)
1061 {
1062         invalidate_inode_buffers(inode);
1063         clear_inode(inode);
1064         dquot_drop(inode);
1065         ext4_discard_preallocations(inode);
1066         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1067         if (EXT4_I(inode)->jinode) {
1068                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1069                                                EXT4_I(inode)->jinode);
1070                 jbd2_free_inode(EXT4_I(inode)->jinode);
1071                 EXT4_I(inode)->jinode = NULL;
1072         }
1073 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1074         fscrypt_put_encryption_info(inode, NULL);
1075 #endif
1076 }
1077
1078 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1079                                         u64 ino, u32 generation)
1080 {
1081         struct inode *inode;
1082
1083         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1084                 return ERR_PTR(-ESTALE);
1085         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1086                 return ERR_PTR(-ESTALE);
1087
1088         /* iget isn't really right if the inode is currently unallocated!!
1089          *
1090          * ext4_read_inode will return a bad_inode if the inode had been
1091          * deleted, so we should be safe.
1092          *
1093          * Currently we don't know the generation for parent directory, so
1094          * a generation of 0 means "accept any"
1095          */
1096         inode = ext4_iget_normal(sb, ino);
1097         if (IS_ERR(inode))
1098                 return ERR_CAST(inode);
1099         if (generation && inode->i_generation != generation) {
1100                 iput(inode);
1101                 return ERR_PTR(-ESTALE);
1102         }
1103
1104         return inode;
1105 }
1106
1107 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1108                                         int fh_len, int fh_type)
1109 {
1110         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1111                                     ext4_nfs_get_inode);
1112 }
1113
1114 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1115                                         int fh_len, int fh_type)
1116 {
1117         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1118                                     ext4_nfs_get_inode);
1119 }
1120
1121 /*
1122  * Try to release metadata pages (indirect blocks, directories) which are
1123  * mapped via the block device.  Since these pages could have journal heads
1124  * which would prevent try_to_free_buffers() from freeing them, we must use
1125  * jbd2 layer's try_to_free_buffers() function to release them.
1126  */
1127 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1128                                  gfp_t wait)
1129 {
1130         journal_t *journal = EXT4_SB(sb)->s_journal;
1131
1132         WARN_ON(PageChecked(page));
1133         if (!page_has_buffers(page))
1134                 return 0;
1135         if (journal)
1136                 return jbd2_journal_try_to_free_buffers(journal, page,
1137                                                 wait & ~__GFP_DIRECT_RECLAIM);
1138         return try_to_free_buffers(page);
1139 }
1140
1141 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1142 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1143 {
1144         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1145                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1146 }
1147
1148 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1149                                                         void *fs_data)
1150 {
1151         handle_t *handle = fs_data;
1152         int res, res2, credits, retries = 0;
1153
1154         /*
1155          * Encrypting the root directory is not allowed because e2fsck expects
1156          * lost+found to exist and be unencrypted, and encrypting the root
1157          * directory would imply encrypting the lost+found directory as well as
1158          * the filename "lost+found" itself.
1159          */
1160         if (inode->i_ino == EXT4_ROOT_INO)
1161                 return -EPERM;
1162
1163         res = ext4_convert_inline_data(inode);
1164         if (res)
1165                 return res;
1166
1167         /*
1168          * If a journal handle was specified, then the encryption context is
1169          * being set on a new inode via inheritance and is part of a larger
1170          * transaction to create the inode.  Otherwise the encryption context is
1171          * being set on an existing inode in its own transaction.  Only in the
1172          * latter case should the "retry on ENOSPC" logic be used.
1173          */
1174
1175         if (handle) {
1176                 res = ext4_xattr_set_handle(handle, inode,
1177                                             EXT4_XATTR_INDEX_ENCRYPTION,
1178                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1179                                             ctx, len, 0);
1180                 if (!res) {
1181                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1182                         ext4_clear_inode_state(inode,
1183                                         EXT4_STATE_MAY_INLINE_DATA);
1184                         /*
1185                          * Update inode->i_flags - e.g. S_DAX may get disabled
1186                          */
1187                         ext4_set_inode_flags(inode);
1188                 }
1189                 return res;
1190         }
1191
1192         res = dquot_initialize(inode);
1193         if (res)
1194                 return res;
1195 retry:
1196         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1197                                      &credits);
1198         if (res)
1199                 return res;
1200
1201         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1202         if (IS_ERR(handle))
1203                 return PTR_ERR(handle);
1204
1205         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1206                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1207                                     ctx, len, 0);
1208         if (!res) {
1209                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1210                 /* Update inode->i_flags - e.g. S_DAX may get disabled */
1211                 ext4_set_inode_flags(inode);
1212                 res = ext4_mark_inode_dirty(handle, inode);
1213                 if (res)
1214                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1215         }
1216         res2 = ext4_journal_stop(handle);
1217
1218         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1219                 goto retry;
1220         if (!res)
1221                 res = res2;
1222         return res;
1223 }
1224
1225 static bool ext4_dummy_context(struct inode *inode)
1226 {
1227         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1228 }
1229
1230 static unsigned ext4_max_namelen(struct inode *inode)
1231 {
1232         return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
1233                 EXT4_NAME_LEN;
1234 }
1235
1236 static const struct fscrypt_operations ext4_cryptops = {
1237         .key_prefix             = "ext4:",
1238         .get_context            = ext4_get_context,
1239         .set_context            = ext4_set_context,
1240         .dummy_context          = ext4_dummy_context,
1241         .is_encrypted           = ext4_encrypted_inode,
1242         .empty_dir              = ext4_empty_dir,
1243         .max_namelen            = ext4_max_namelen,
1244 };
1245 #else
1246 static const struct fscrypt_operations ext4_cryptops = {
1247         .is_encrypted           = ext4_encrypted_inode,
1248 };
1249 #endif
1250
1251 #ifdef CONFIG_QUOTA
1252 static const char * const quotatypes[] = INITQFNAMES;
1253 #define QTYPE2NAME(t) (quotatypes[t])
1254
1255 static int ext4_write_dquot(struct dquot *dquot);
1256 static int ext4_acquire_dquot(struct dquot *dquot);
1257 static int ext4_release_dquot(struct dquot *dquot);
1258 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1259 static int ext4_write_info(struct super_block *sb, int type);
1260 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1261                          const struct path *path);
1262 static int ext4_quota_on_mount(struct super_block *sb, int type);
1263 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1264                                size_t len, loff_t off);
1265 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1266                                 const char *data, size_t len, loff_t off);
1267 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1268                              unsigned int flags);
1269 static int ext4_enable_quotas(struct super_block *sb);
1270 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1271
1272 static struct dquot **ext4_get_dquots(struct inode *inode)
1273 {
1274         return EXT4_I(inode)->i_dquot;
1275 }
1276
1277 static const struct dquot_operations ext4_quota_operations = {
1278         .get_reserved_space     = ext4_get_reserved_space,
1279         .write_dquot            = ext4_write_dquot,
1280         .acquire_dquot          = ext4_acquire_dquot,
1281         .release_dquot          = ext4_release_dquot,
1282         .mark_dirty             = ext4_mark_dquot_dirty,
1283         .write_info             = ext4_write_info,
1284         .alloc_dquot            = dquot_alloc,
1285         .destroy_dquot          = dquot_destroy,
1286         .get_projid             = ext4_get_projid,
1287         .get_inode_usage        = ext4_get_inode_usage,
1288         .get_next_id            = ext4_get_next_id,
1289 };
1290
1291 static const struct quotactl_ops ext4_qctl_operations = {
1292         .quota_on       = ext4_quota_on,
1293         .quota_off      = ext4_quota_off,
1294         .quota_sync     = dquot_quota_sync,
1295         .get_state      = dquot_get_state,
1296         .set_info       = dquot_set_dqinfo,
1297         .get_dqblk      = dquot_get_dqblk,
1298         .set_dqblk      = dquot_set_dqblk,
1299         .get_nextdqblk  = dquot_get_next_dqblk,
1300 };
1301 #endif
1302
1303 static const struct super_operations ext4_sops = {
1304         .alloc_inode    = ext4_alloc_inode,
1305         .destroy_inode  = ext4_destroy_inode,
1306         .write_inode    = ext4_write_inode,
1307         .dirty_inode    = ext4_dirty_inode,
1308         .drop_inode     = ext4_drop_inode,
1309         .evict_inode    = ext4_evict_inode,
1310         .put_super      = ext4_put_super,
1311         .sync_fs        = ext4_sync_fs,
1312         .freeze_fs      = ext4_freeze,
1313         .unfreeze_fs    = ext4_unfreeze,
1314         .statfs         = ext4_statfs,
1315         .remount_fs     = ext4_remount,
1316         .show_options   = ext4_show_options,
1317 #ifdef CONFIG_QUOTA
1318         .quota_read     = ext4_quota_read,
1319         .quota_write    = ext4_quota_write,
1320         .get_dquots     = ext4_get_dquots,
1321 #endif
1322         .bdev_try_to_free_page = bdev_try_to_free_page,
1323 };
1324
1325 static const struct export_operations ext4_export_ops = {
1326         .fh_to_dentry = ext4_fh_to_dentry,
1327         .fh_to_parent = ext4_fh_to_parent,
1328         .get_parent = ext4_get_parent,
1329 };
1330
1331 enum {
1332         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1333         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1334         Opt_nouid32, Opt_debug, Opt_removed,
1335         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1336         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1337         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1338         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1339         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1340         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1341         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1342         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1343         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1344         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1345         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1346         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1347         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1348         Opt_inode_readahead_blks, Opt_journal_ioprio,
1349         Opt_dioread_nolock, Opt_dioread_lock,
1350         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1351         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1352 };
1353
1354 static const match_table_t tokens = {
1355         {Opt_bsd_df, "bsddf"},
1356         {Opt_minix_df, "minixdf"},
1357         {Opt_grpid, "grpid"},
1358         {Opt_grpid, "bsdgroups"},
1359         {Opt_nogrpid, "nogrpid"},
1360         {Opt_nogrpid, "sysvgroups"},
1361         {Opt_resgid, "resgid=%u"},
1362         {Opt_resuid, "resuid=%u"},
1363         {Opt_sb, "sb=%u"},
1364         {Opt_err_cont, "errors=continue"},
1365         {Opt_err_panic, "errors=panic"},
1366         {Opt_err_ro, "errors=remount-ro"},
1367         {Opt_nouid32, "nouid32"},
1368         {Opt_debug, "debug"},
1369         {Opt_removed, "oldalloc"},
1370         {Opt_removed, "orlov"},
1371         {Opt_user_xattr, "user_xattr"},
1372         {Opt_nouser_xattr, "nouser_xattr"},
1373         {Opt_acl, "acl"},
1374         {Opt_noacl, "noacl"},
1375         {Opt_noload, "norecovery"},
1376         {Opt_noload, "noload"},
1377         {Opt_removed, "nobh"},
1378         {Opt_removed, "bh"},
1379         {Opt_commit, "commit=%u"},
1380         {Opt_min_batch_time, "min_batch_time=%u"},
1381         {Opt_max_batch_time, "max_batch_time=%u"},
1382         {Opt_journal_dev, "journal_dev=%u"},
1383         {Opt_journal_path, "journal_path=%s"},
1384         {Opt_journal_checksum, "journal_checksum"},
1385         {Opt_nojournal_checksum, "nojournal_checksum"},
1386         {Opt_journal_async_commit, "journal_async_commit"},
1387         {Opt_abort, "abort"},
1388         {Opt_data_journal, "data=journal"},
1389         {Opt_data_ordered, "data=ordered"},
1390         {Opt_data_writeback, "data=writeback"},
1391         {Opt_data_err_abort, "data_err=abort"},
1392         {Opt_data_err_ignore, "data_err=ignore"},
1393         {Opt_offusrjquota, "usrjquota="},
1394         {Opt_usrjquota, "usrjquota=%s"},
1395         {Opt_offgrpjquota, "grpjquota="},
1396         {Opt_grpjquota, "grpjquota=%s"},
1397         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1398         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1399         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1400         {Opt_grpquota, "grpquota"},
1401         {Opt_noquota, "noquota"},
1402         {Opt_quota, "quota"},
1403         {Opt_usrquota, "usrquota"},
1404         {Opt_prjquota, "prjquota"},
1405         {Opt_barrier, "barrier=%u"},
1406         {Opt_barrier, "barrier"},
1407         {Opt_nobarrier, "nobarrier"},
1408         {Opt_i_version, "i_version"},
1409         {Opt_dax, "dax"},
1410         {Opt_stripe, "stripe=%u"},
1411         {Opt_delalloc, "delalloc"},
1412         {Opt_lazytime, "lazytime"},
1413         {Opt_nolazytime, "nolazytime"},
1414         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1415         {Opt_nodelalloc, "nodelalloc"},
1416         {Opt_removed, "mblk_io_submit"},
1417         {Opt_removed, "nomblk_io_submit"},
1418         {Opt_block_validity, "block_validity"},
1419         {Opt_noblock_validity, "noblock_validity"},
1420         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1421         {Opt_journal_ioprio, "journal_ioprio=%u"},
1422         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1423         {Opt_auto_da_alloc, "auto_da_alloc"},
1424         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1425         {Opt_dioread_nolock, "dioread_nolock"},
1426         {Opt_dioread_lock, "dioread_lock"},
1427         {Opt_discard, "discard"},
1428         {Opt_nodiscard, "nodiscard"},
1429         {Opt_init_itable, "init_itable=%u"},
1430         {Opt_init_itable, "init_itable"},
1431         {Opt_noinit_itable, "noinit_itable"},
1432         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1433         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1434         {Opt_nombcache, "nombcache"},
1435         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1436         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1437         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1438         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1439         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1440         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1441         {Opt_err, NULL},
1442 };
1443
1444 static ext4_fsblk_t get_sb_block(void **data)
1445 {
1446         ext4_fsblk_t    sb_block;
1447         char            *options = (char *) *data;
1448
1449         if (!options || strncmp(options, "sb=", 3) != 0)
1450                 return 1;       /* Default location */
1451
1452         options += 3;
1453         /* TODO: use simple_strtoll with >32bit ext4 */
1454         sb_block = simple_strtoul(options, &options, 0);
1455         if (*options && *options != ',') {
1456                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1457                        (char *) *data);
1458                 return 1;
1459         }
1460         if (*options == ',')
1461                 options++;
1462         *data = (void *) options;
1463
1464         return sb_block;
1465 }
1466
1467 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1468 static const char deprecated_msg[] =
1469         "Mount option \"%s\" will be removed by %s\n"
1470         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1471
1472 #ifdef CONFIG_QUOTA
1473 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1474 {
1475         struct ext4_sb_info *sbi = EXT4_SB(sb);
1476         char *qname;
1477         int ret = -1;
1478
1479         if (sb_any_quota_loaded(sb) &&
1480                 !sbi->s_qf_names[qtype]) {
1481                 ext4_msg(sb, KERN_ERR,
1482                         "Cannot change journaled "
1483                         "quota options when quota turned on");
1484                 return -1;
1485         }
1486         if (ext4_has_feature_quota(sb)) {
1487                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1488                          "ignored when QUOTA feature is enabled");
1489                 return 1;
1490         }
1491         qname = match_strdup(args);
1492         if (!qname) {
1493                 ext4_msg(sb, KERN_ERR,
1494                         "Not enough memory for storing quotafile name");
1495                 return -1;
1496         }
1497         if (sbi->s_qf_names[qtype]) {
1498                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1499                         ret = 1;
1500                 else
1501                         ext4_msg(sb, KERN_ERR,
1502                                  "%s quota file already specified",
1503                                  QTYPE2NAME(qtype));
1504                 goto errout;
1505         }
1506         if (strchr(qname, '/')) {
1507                 ext4_msg(sb, KERN_ERR,
1508                         "quotafile must be on filesystem root");
1509                 goto errout;
1510         }
1511         sbi->s_qf_names[qtype] = qname;
1512         set_opt(sb, QUOTA);
1513         return 1;
1514 errout:
1515         kfree(qname);
1516         return ret;
1517 }
1518
1519 static int clear_qf_name(struct super_block *sb, int qtype)
1520 {
1521
1522         struct ext4_sb_info *sbi = EXT4_SB(sb);
1523
1524         if (sb_any_quota_loaded(sb) &&
1525                 sbi->s_qf_names[qtype]) {
1526                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1527                         " when quota turned on");
1528                 return -1;
1529         }
1530         kfree(sbi->s_qf_names[qtype]);
1531         sbi->s_qf_names[qtype] = NULL;
1532         return 1;
1533 }
1534 #endif
1535
1536 #define MOPT_SET        0x0001
1537 #define MOPT_CLEAR      0x0002
1538 #define MOPT_NOSUPPORT  0x0004
1539 #define MOPT_EXPLICIT   0x0008
1540 #define MOPT_CLEAR_ERR  0x0010
1541 #define MOPT_GTE0       0x0020
1542 #ifdef CONFIG_QUOTA
1543 #define MOPT_Q          0
1544 #define MOPT_QFMT       0x0040
1545 #else
1546 #define MOPT_Q          MOPT_NOSUPPORT
1547 #define MOPT_QFMT       MOPT_NOSUPPORT
1548 #endif
1549 #define MOPT_DATAJ      0x0080
1550 #define MOPT_NO_EXT2    0x0100
1551 #define MOPT_NO_EXT3    0x0200
1552 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1553 #define MOPT_STRING     0x0400
1554
1555 static const struct mount_opts {
1556         int     token;
1557         int     mount_opt;
1558         int     flags;
1559 } ext4_mount_opts[] = {
1560         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1561         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1562         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1563         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1564         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1565         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1566         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1567          MOPT_EXT4_ONLY | MOPT_SET},
1568         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1569          MOPT_EXT4_ONLY | MOPT_CLEAR},
1570         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1571         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1572         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1573          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1574         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1575          MOPT_EXT4_ONLY | MOPT_CLEAR},
1576         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1577          MOPT_EXT4_ONLY | MOPT_CLEAR},
1578         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1579          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1580         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1581                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1582          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1583         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1584         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1585         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1586         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1587         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1588          MOPT_NO_EXT2},
1589         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1590          MOPT_NO_EXT2},
1591         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1592         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1593         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1594         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1595         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1596         {Opt_commit, 0, MOPT_GTE0},
1597         {Opt_max_batch_time, 0, MOPT_GTE0},
1598         {Opt_min_batch_time, 0, MOPT_GTE0},
1599         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1600         {Opt_init_itable, 0, MOPT_GTE0},
1601         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1602         {Opt_stripe, 0, MOPT_GTE0},
1603         {Opt_resuid, 0, MOPT_GTE0},
1604         {Opt_resgid, 0, MOPT_GTE0},
1605         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1606         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1607         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1608         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1609         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1610         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1611          MOPT_NO_EXT2 | MOPT_DATAJ},
1612         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1613         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1614 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1615         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1616         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1617 #else
1618         {Opt_acl, 0, MOPT_NOSUPPORT},
1619         {Opt_noacl, 0, MOPT_NOSUPPORT},
1620 #endif
1621         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1622         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1623         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1624         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1625         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1626                                                         MOPT_SET | MOPT_Q},
1627         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1628                                                         MOPT_SET | MOPT_Q},
1629         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1630                                                         MOPT_SET | MOPT_Q},
1631         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1632                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1633                                                         MOPT_CLEAR | MOPT_Q},
1634         {Opt_usrjquota, 0, MOPT_Q},
1635         {Opt_grpjquota, 0, MOPT_Q},
1636         {Opt_offusrjquota, 0, MOPT_Q},
1637         {Opt_offgrpjquota, 0, MOPT_Q},
1638         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1639         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1640         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1641         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1642         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1643         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1644         {Opt_err, 0, 0}
1645 };
1646
1647 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1648                             substring_t *args, unsigned long *journal_devnum,
1649                             unsigned int *journal_ioprio, int is_remount)
1650 {
1651         struct ext4_sb_info *sbi = EXT4_SB(sb);
1652         const struct mount_opts *m;
1653         kuid_t uid;
1654         kgid_t gid;
1655         int arg = 0;
1656
1657 #ifdef CONFIG_QUOTA
1658         if (token == Opt_usrjquota)
1659                 return set_qf_name(sb, USRQUOTA, &args[0]);
1660         else if (token == Opt_grpjquota)
1661                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1662         else if (token == Opt_offusrjquota)
1663                 return clear_qf_name(sb, USRQUOTA);
1664         else if (token == Opt_offgrpjquota)
1665                 return clear_qf_name(sb, GRPQUOTA);
1666 #endif
1667         switch (token) {
1668         case Opt_noacl:
1669         case Opt_nouser_xattr:
1670                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1671                 break;
1672         case Opt_sb:
1673                 return 1;       /* handled by get_sb_block() */
1674         case Opt_removed:
1675                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1676                 return 1;
1677         case Opt_abort:
1678                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1679                 return 1;
1680         case Opt_i_version:
1681                 sb->s_flags |= MS_I_VERSION;
1682                 return 1;
1683         case Opt_lazytime:
1684                 sb->s_flags |= MS_LAZYTIME;
1685                 return 1;
1686         case Opt_nolazytime:
1687                 sb->s_flags &= ~MS_LAZYTIME;
1688                 return 1;
1689         }
1690
1691         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1692                 if (token == m->token)
1693                         break;
1694
1695         if (m->token == Opt_err) {
1696                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1697                          "or missing value", opt);
1698                 return -1;
1699         }
1700
1701         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1702                 ext4_msg(sb, KERN_ERR,
1703                          "Mount option \"%s\" incompatible with ext2", opt);
1704                 return -1;
1705         }
1706         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1707                 ext4_msg(sb, KERN_ERR,
1708                          "Mount option \"%s\" incompatible with ext3", opt);
1709                 return -1;
1710         }
1711
1712         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1713                 return -1;
1714         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1715                 return -1;
1716         if (m->flags & MOPT_EXPLICIT) {
1717                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1718                         set_opt2(sb, EXPLICIT_DELALLOC);
1719                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1720                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1721                 } else
1722                         return -1;
1723         }
1724         if (m->flags & MOPT_CLEAR_ERR)
1725                 clear_opt(sb, ERRORS_MASK);
1726         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1727                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1728                          "options when quota turned on");
1729                 return -1;
1730         }
1731
1732         if (m->flags & MOPT_NOSUPPORT) {
1733                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1734         } else if (token == Opt_commit) {
1735                 if (arg == 0)
1736                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1737                 sbi->s_commit_interval = HZ * arg;
1738         } else if (token == Opt_debug_want_extra_isize) {
1739                 sbi->s_want_extra_isize = arg;
1740         } else if (token == Opt_max_batch_time) {
1741                 sbi->s_max_batch_time = arg;
1742         } else if (token == Opt_min_batch_time) {
1743                 sbi->s_min_batch_time = arg;
1744         } else if (token == Opt_inode_readahead_blks) {
1745                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1746                         ext4_msg(sb, KERN_ERR,
1747                                  "EXT4-fs: inode_readahead_blks must be "
1748                                  "0 or a power of 2 smaller than 2^31");
1749                         return -1;
1750                 }
1751                 sbi->s_inode_readahead_blks = arg;
1752         } else if (token == Opt_init_itable) {
1753                 set_opt(sb, INIT_INODE_TABLE);
1754                 if (!args->from)
1755                         arg = EXT4_DEF_LI_WAIT_MULT;
1756                 sbi->s_li_wait_mult = arg;
1757         } else if (token == Opt_max_dir_size_kb) {
1758                 sbi->s_max_dir_size_kb = arg;
1759         } else if (token == Opt_stripe) {
1760                 sbi->s_stripe = arg;
1761         } else if (token == Opt_resuid) {
1762                 uid = make_kuid(current_user_ns(), arg);
1763                 if (!uid_valid(uid)) {
1764                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1765                         return -1;
1766                 }
1767                 sbi->s_resuid = uid;
1768         } else if (token == Opt_resgid) {
1769                 gid = make_kgid(current_user_ns(), arg);
1770                 if (!gid_valid(gid)) {
1771                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1772                         return -1;
1773                 }
1774                 sbi->s_resgid = gid;
1775         } else if (token == Opt_journal_dev) {
1776                 if (is_remount) {
1777                         ext4_msg(sb, KERN_ERR,
1778                                  "Cannot specify journal on remount");
1779                         return -1;
1780                 }
1781                 *journal_devnum = arg;
1782         } else if (token == Opt_journal_path) {
1783                 char *journal_path;
1784                 struct inode *journal_inode;
1785                 struct path path;
1786                 int error;
1787
1788                 if (is_remount) {
1789                         ext4_msg(sb, KERN_ERR,
1790                                  "Cannot specify journal on remount");
1791                         return -1;
1792                 }
1793                 journal_path = match_strdup(&args[0]);
1794                 if (!journal_path) {
1795                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1796                                 "journal device string");
1797                         return -1;
1798                 }
1799
1800                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1801                 if (error) {
1802                         ext4_msg(sb, KERN_ERR, "error: could not find "
1803                                 "journal device path: error %d", error);
1804                         kfree(journal_path);
1805                         return -1;
1806                 }
1807
1808                 journal_inode = d_inode(path.dentry);
1809                 if (!S_ISBLK(journal_inode->i_mode)) {
1810                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1811                                 "is not a block device", journal_path);
1812                         path_put(&path);
1813                         kfree(journal_path);
1814                         return -1;
1815                 }
1816
1817                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1818                 path_put(&path);
1819                 kfree(journal_path);
1820         } else if (token == Opt_journal_ioprio) {
1821                 if (arg > 7) {
1822                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1823                                  " (must be 0-7)");
1824                         return -1;
1825                 }
1826                 *journal_ioprio =
1827                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1828         } else if (token == Opt_test_dummy_encryption) {
1829 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1830                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1831                 ext4_msg(sb, KERN_WARNING,
1832                          "Test dummy encryption mode enabled");
1833 #else
1834                 ext4_msg(sb, KERN_WARNING,
1835                          "Test dummy encryption mount option ignored");
1836 #endif
1837         } else if (m->flags & MOPT_DATAJ) {
1838                 if (is_remount) {
1839                         if (!sbi->s_journal)
1840                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1841                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1842                                 ext4_msg(sb, KERN_ERR,
1843                                          "Cannot change data mode on remount");
1844                                 return -1;
1845                         }
1846                 } else {
1847                         clear_opt(sb, DATA_FLAGS);
1848                         sbi->s_mount_opt |= m->mount_opt;
1849                 }
1850 #ifdef CONFIG_QUOTA
1851         } else if (m->flags & MOPT_QFMT) {
1852                 if (sb_any_quota_loaded(sb) &&
1853                     sbi->s_jquota_fmt != m->mount_opt) {
1854                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1855                                  "quota options when quota turned on");
1856                         return -1;
1857                 }
1858                 if (ext4_has_feature_quota(sb)) {
1859                         ext4_msg(sb, KERN_INFO,
1860                                  "Quota format mount options ignored "
1861                                  "when QUOTA feature is enabled");
1862                         return 1;
1863                 }
1864                 sbi->s_jquota_fmt = m->mount_opt;
1865 #endif
1866         } else if (token == Opt_dax) {
1867 #ifdef CONFIG_FS_DAX
1868                 ext4_msg(sb, KERN_WARNING,
1869                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1870                         sbi->s_mount_opt |= m->mount_opt;
1871 #else
1872                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1873                 return -1;
1874 #endif
1875         } else if (token == Opt_data_err_abort) {
1876                 sbi->s_mount_opt |= m->mount_opt;
1877         } else if (token == Opt_data_err_ignore) {
1878                 sbi->s_mount_opt &= ~m->mount_opt;
1879         } else {
1880                 if (!args->from)
1881                         arg = 1;
1882                 if (m->flags & MOPT_CLEAR)
1883                         arg = !arg;
1884                 else if (unlikely(!(m->flags & MOPT_SET))) {
1885                         ext4_msg(sb, KERN_WARNING,
1886                                  "buggy handling of option %s", opt);
1887                         WARN_ON(1);
1888                         return -1;
1889                 }
1890                 if (arg != 0)
1891                         sbi->s_mount_opt |= m->mount_opt;
1892                 else
1893                         sbi->s_mount_opt &= ~m->mount_opt;
1894         }
1895         return 1;
1896 }
1897
1898 static int parse_options(char *options, struct super_block *sb,
1899                          unsigned long *journal_devnum,
1900                          unsigned int *journal_ioprio,
1901                          int is_remount)
1902 {
1903         struct ext4_sb_info *sbi = EXT4_SB(sb);
1904         char *p;
1905         substring_t args[MAX_OPT_ARGS];
1906         int token;
1907
1908         if (!options)
1909                 return 1;
1910
1911         while ((p = strsep(&options, ",")) != NULL) {
1912                 if (!*p)
1913                         continue;
1914                 /*
1915                  * Initialize args struct so we know whether arg was
1916                  * found; some options take optional arguments.
1917                  */
1918                 args[0].to = args[0].from = NULL;
1919                 token = match_token(p, tokens, args);
1920                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1921                                      journal_ioprio, is_remount) < 0)
1922                         return 0;
1923         }
1924 #ifdef CONFIG_QUOTA
1925         /*
1926          * We do the test below only for project quotas. 'usrquota' and
1927          * 'grpquota' mount options are allowed even without quota feature
1928          * to support legacy quotas in quota files.
1929          */
1930         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
1931                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
1932                          "Cannot enable project quota enforcement.");
1933                 return 0;
1934         }
1935         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1936                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1937                         clear_opt(sb, USRQUOTA);
1938
1939                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1940                         clear_opt(sb, GRPQUOTA);
1941
1942                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1943                         ext4_msg(sb, KERN_ERR, "old and new quota "
1944                                         "format mixing");
1945                         return 0;
1946                 }
1947
1948                 if (!sbi->s_jquota_fmt) {
1949                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1950                                         "not specified");
1951                         return 0;
1952                 }
1953         }
1954 #endif
1955         if (test_opt(sb, DIOREAD_NOLOCK)) {
1956                 int blocksize =
1957                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1958
1959                 if (blocksize < PAGE_SIZE) {
1960                         ext4_msg(sb, KERN_ERR, "can't mount with "
1961                                  "dioread_nolock if block size != PAGE_SIZE");
1962                         return 0;
1963                 }
1964         }
1965         return 1;
1966 }
1967
1968 static inline void ext4_show_quota_options(struct seq_file *seq,
1969                                            struct super_block *sb)
1970 {
1971 #if defined(CONFIG_QUOTA)
1972         struct ext4_sb_info *sbi = EXT4_SB(sb);
1973
1974         if (sbi->s_jquota_fmt) {
1975                 char *fmtname = "";
1976
1977                 switch (sbi->s_jquota_fmt) {
1978                 case QFMT_VFS_OLD:
1979                         fmtname = "vfsold";
1980                         break;
1981                 case QFMT_VFS_V0:
1982                         fmtname = "vfsv0";
1983                         break;
1984                 case QFMT_VFS_V1:
1985                         fmtname = "vfsv1";
1986                         break;
1987                 }
1988                 seq_printf(seq, ",jqfmt=%s", fmtname);
1989         }
1990
1991         if (sbi->s_qf_names[USRQUOTA])
1992                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1993
1994         if (sbi->s_qf_names[GRPQUOTA])
1995                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1996 #endif
1997 }
1998
1999 static const char *token2str(int token)
2000 {
2001         const struct match_token *t;
2002
2003         for (t = tokens; t->token != Opt_err; t++)
2004                 if (t->token == token && !strchr(t->pattern, '='))
2005                         break;
2006         return t->pattern;
2007 }
2008
2009 /*
2010  * Show an option if
2011  *  - it's set to a non-default value OR
2012  *  - if the per-sb default is different from the global default
2013  */
2014 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2015                               int nodefs)
2016 {
2017         struct ext4_sb_info *sbi = EXT4_SB(sb);
2018         struct ext4_super_block *es = sbi->s_es;
2019         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
2020         const struct mount_opts *m;
2021         char sep = nodefs ? '\n' : ',';
2022
2023 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2024 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2025
2026         if (sbi->s_sb_block != 1)
2027                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2028
2029         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2030                 int want_set = m->flags & MOPT_SET;
2031                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2032                     (m->flags & MOPT_CLEAR_ERR))
2033                         continue;
2034                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2035                         continue; /* skip if same as the default */
2036                 if ((want_set &&
2037                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2038                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2039                         continue; /* select Opt_noFoo vs Opt_Foo */
2040                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2041         }
2042
2043         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2044             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2045                 SEQ_OPTS_PRINT("resuid=%u",
2046                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2047         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2048             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2049                 SEQ_OPTS_PRINT("resgid=%u",
2050                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2051         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2052         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2053                 SEQ_OPTS_PUTS("errors=remount-ro");
2054         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2055                 SEQ_OPTS_PUTS("errors=continue");
2056         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2057                 SEQ_OPTS_PUTS("errors=panic");
2058         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2059                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2060         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2061                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2062         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2063                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2064         if (sb->s_flags & MS_I_VERSION)
2065                 SEQ_OPTS_PUTS("i_version");
2066         if (nodefs || sbi->s_stripe)
2067                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2068         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
2069                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2070                         SEQ_OPTS_PUTS("data=journal");
2071                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2072                         SEQ_OPTS_PUTS("data=ordered");
2073                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2074                         SEQ_OPTS_PUTS("data=writeback");
2075         }
2076         if (nodefs ||
2077             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2078                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2079                                sbi->s_inode_readahead_blks);
2080
2081         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
2082                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2083                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2084         if (nodefs || sbi->s_max_dir_size_kb)
2085                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2086         if (test_opt(sb, DATA_ERR_ABORT))
2087                 SEQ_OPTS_PUTS("data_err=abort");
2088
2089         ext4_show_quota_options(seq, sb);
2090         return 0;
2091 }
2092
2093 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2094 {
2095         return _ext4_show_options(seq, root->d_sb, 0);
2096 }
2097
2098 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2099 {
2100         struct super_block *sb = seq->private;
2101         int rc;
2102
2103         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
2104         rc = _ext4_show_options(seq, sb, 1);
2105         seq_puts(seq, "\n");
2106         return rc;
2107 }
2108
2109 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2110                             int read_only)
2111 {
2112         struct ext4_sb_info *sbi = EXT4_SB(sb);
2113         int res = 0;
2114
2115         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2116                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2117                          "forcing read-only mode");
2118                 res = MS_RDONLY;
2119         }
2120         if (read_only)
2121                 goto done;
2122         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2123                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2124                          "running e2fsck is recommended");
2125         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2126                 ext4_msg(sb, KERN_WARNING,
2127                          "warning: mounting fs with errors, "
2128                          "running e2fsck is recommended");
2129         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2130                  le16_to_cpu(es->s_mnt_count) >=
2131                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2132                 ext4_msg(sb, KERN_WARNING,
2133                          "warning: maximal mount count reached, "
2134                          "running e2fsck is recommended");
2135         else if (le32_to_cpu(es->s_checkinterval) &&
2136                 (le32_to_cpu(es->s_lastcheck) +
2137                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
2138                 ext4_msg(sb, KERN_WARNING,
2139                          "warning: checktime reached, "
2140                          "running e2fsck is recommended");
2141         if (!sbi->s_journal)
2142                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2143         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2144                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2145         le16_add_cpu(&es->s_mnt_count, 1);
2146         es->s_mtime = cpu_to_le32(get_seconds());
2147         ext4_update_dynamic_rev(sb);
2148         if (sbi->s_journal)
2149                 ext4_set_feature_journal_needs_recovery(sb);
2150
2151         ext4_commit_super(sb, 1);
2152 done:
2153         if (test_opt(sb, DEBUG))
2154                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2155                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2156                         sb->s_blocksize,
2157                         sbi->s_groups_count,
2158                         EXT4_BLOCKS_PER_GROUP(sb),
2159                         EXT4_INODES_PER_GROUP(sb),
2160                         sbi->s_mount_opt, sbi->s_mount_opt2);
2161
2162         cleancache_init_fs(sb);
2163         return res;
2164 }
2165
2166 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2167 {
2168         struct ext4_sb_info *sbi = EXT4_SB(sb);
2169         struct flex_groups *new_groups;
2170         int size;
2171
2172         if (!sbi->s_log_groups_per_flex)
2173                 return 0;
2174
2175         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2176         if (size <= sbi->s_flex_groups_allocated)
2177                 return 0;
2178
2179         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2180         new_groups = kvzalloc(size, GFP_KERNEL);
2181         if (!new_groups) {
2182                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2183                          size / (int) sizeof(struct flex_groups));
2184                 return -ENOMEM;
2185         }
2186
2187         if (sbi->s_flex_groups) {
2188                 memcpy(new_groups, sbi->s_flex_groups,
2189                        (sbi->s_flex_groups_allocated *
2190                         sizeof(struct flex_groups)));
2191                 kvfree(sbi->s_flex_groups);
2192         }
2193         sbi->s_flex_groups = new_groups;
2194         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2195         return 0;
2196 }
2197
2198 static int ext4_fill_flex_info(struct super_block *sb)
2199 {
2200         struct ext4_sb_info *sbi = EXT4_SB(sb);
2201         struct ext4_group_desc *gdp = NULL;
2202         ext4_group_t flex_group;
2203         int i, err;
2204
2205         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2206         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2207                 sbi->s_log_groups_per_flex = 0;
2208                 return 1;
2209         }
2210
2211         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2212         if (err)
2213                 goto failed;
2214
2215         for (i = 0; i < sbi->s_groups_count; i++) {
2216                 gdp = ext4_get_group_desc(sb, i, NULL);
2217
2218                 flex_group = ext4_flex_group(sbi, i);
2219                 atomic_add(ext4_free_inodes_count(sb, gdp),
2220                            &sbi->s_flex_groups[flex_group].free_inodes);
2221                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2222                              &sbi->s_flex_groups[flex_group].free_clusters);
2223                 atomic_add(ext4_used_dirs_count(sb, gdp),
2224                            &sbi->s_flex_groups[flex_group].used_dirs);
2225         }
2226
2227         return 1;
2228 failed:
2229         return 0;
2230 }
2231
2232 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2233                                    struct ext4_group_desc *gdp)
2234 {
2235         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2236         __u16 crc = 0;
2237         __le32 le_group = cpu_to_le32(block_group);
2238         struct ext4_sb_info *sbi = EXT4_SB(sb);
2239
2240         if (ext4_has_metadata_csum(sbi->s_sb)) {
2241                 /* Use new metadata_csum algorithm */
2242                 __u32 csum32;
2243                 __u16 dummy_csum = 0;
2244
2245                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2246                                      sizeof(le_group));
2247                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2248                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2249                                      sizeof(dummy_csum));
2250                 offset += sizeof(dummy_csum);
2251                 if (offset < sbi->s_desc_size)
2252                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2253                                              sbi->s_desc_size - offset);
2254
2255                 crc = csum32 & 0xFFFF;
2256                 goto out;
2257         }
2258
2259         /* old crc16 code */
2260         if (!ext4_has_feature_gdt_csum(sb))
2261                 return 0;
2262
2263         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2264         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2265         crc = crc16(crc, (__u8 *)gdp, offset);
2266         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2267         /* for checksum of struct ext4_group_desc do the rest...*/
2268         if (ext4_has_feature_64bit(sb) &&
2269             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2270                 crc = crc16(crc, (__u8 *)gdp + offset,
2271                             le16_to_cpu(sbi->s_es->s_desc_size) -
2272                                 offset);
2273
2274 out:
2275         return cpu_to_le16(crc);
2276 }
2277
2278 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2279                                 struct ext4_group_desc *gdp)
2280 {
2281         if (ext4_has_group_desc_csum(sb) &&
2282             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2283                 return 0;
2284
2285         return 1;
2286 }
2287
2288 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2289                               struct ext4_group_desc *gdp)
2290 {
2291         if (!ext4_has_group_desc_csum(sb))
2292                 return;
2293         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2294 }
2295
2296 /* Called at mount-time, super-block is locked */
2297 static int ext4_check_descriptors(struct super_block *sb,
2298                                   ext4_fsblk_t sb_block,
2299                                   ext4_group_t *first_not_zeroed)
2300 {
2301         struct ext4_sb_info *sbi = EXT4_SB(sb);
2302         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2303         ext4_fsblk_t last_block;
2304         ext4_fsblk_t block_bitmap;
2305         ext4_fsblk_t inode_bitmap;
2306         ext4_fsblk_t inode_table;
2307         int flexbg_flag = 0;
2308         ext4_group_t i, grp = sbi->s_groups_count;
2309
2310         if (ext4_has_feature_flex_bg(sb))
2311                 flexbg_flag = 1;
2312
2313         ext4_debug("Checking group descriptors");
2314
2315         for (i = 0; i < sbi->s_groups_count; i++) {
2316                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2317
2318                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2319                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2320                 else
2321                         last_block = first_block +
2322                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2323
2324                 if ((grp == sbi->s_groups_count) &&
2325                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2326                         grp = i;
2327
2328                 block_bitmap = ext4_block_bitmap(sb, gdp);
2329                 if (block_bitmap == sb_block) {
2330                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2331                                  "Block bitmap for group %u overlaps "
2332                                  "superblock", i);
2333                 }
2334                 if (block_bitmap < first_block || block_bitmap > last_block) {
2335                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2336                                "Block bitmap for group %u not in group "
2337                                "(block %llu)!", i, block_bitmap);
2338                         return 0;
2339                 }
2340                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2341                 if (inode_bitmap == sb_block) {
2342                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2343                                  "Inode bitmap for group %u overlaps "
2344                                  "superblock", i);
2345                 }
2346                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2347                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2348                                "Inode bitmap for group %u not in group "
2349                                "(block %llu)!", i, inode_bitmap);
2350                         return 0;
2351                 }
2352                 inode_table = ext4_inode_table(sb, gdp);
2353                 if (inode_table == sb_block) {
2354                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2355                                  "Inode table for group %u overlaps "
2356                                  "superblock", i);
2357                 }
2358                 if (inode_table < first_block ||
2359                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2360                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2361                                "Inode table for group %u not in group "
2362                                "(block %llu)!", i, inode_table);
2363                         return 0;
2364                 }
2365                 ext4_lock_group(sb, i);
2366                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2367                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2368                                  "Checksum for group %u failed (%u!=%u)",
2369                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2370                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2371                         if (!(sb->s_flags & MS_RDONLY)) {
2372                                 ext4_unlock_group(sb, i);
2373                                 return 0;
2374                         }
2375                 }
2376                 ext4_unlock_group(sb, i);
2377                 if (!flexbg_flag)
2378                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2379         }
2380         if (NULL != first_not_zeroed)
2381                 *first_not_zeroed = grp;
2382         return 1;
2383 }
2384
2385 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2386  * the superblock) which were deleted from all directories, but held open by
2387  * a process at the time of a crash.  We walk the list and try to delete these
2388  * inodes at recovery time (only with a read-write filesystem).
2389  *
2390  * In order to keep the orphan inode chain consistent during traversal (in
2391  * case of crash during recovery), we link each inode into the superblock
2392  * orphan list_head and handle it the same way as an inode deletion during
2393  * normal operation (which journals the operations for us).
2394  *
2395  * We only do an iget() and an iput() on each inode, which is very safe if we
2396  * accidentally point at an in-use or already deleted inode.  The worst that
2397  * can happen in this case is that we get a "bit already cleared" message from
2398  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2399  * e2fsck was run on this filesystem, and it must have already done the orphan
2400  * inode cleanup for us, so we can safely abort without any further action.
2401  */
2402 static void ext4_orphan_cleanup(struct super_block *sb,
2403                                 struct ext4_super_block *es)
2404 {
2405         unsigned int s_flags = sb->s_flags;
2406         int ret, nr_orphans = 0, nr_truncates = 0;
2407 #ifdef CONFIG_QUOTA
2408         int quota_update = 0;
2409         int i;
2410 #endif
2411         if (!es->s_last_orphan) {
2412                 jbd_debug(4, "no orphan inodes to clean up\n");
2413                 return;
2414         }
2415
2416         if (bdev_read_only(sb->s_bdev)) {
2417                 ext4_msg(sb, KERN_ERR, "write access "
2418                         "unavailable, skipping orphan cleanup");
2419                 return;
2420         }
2421
2422         /* Check if feature set would not allow a r/w mount */
2423         if (!ext4_feature_set_ok(sb, 0)) {
2424                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2425                          "unknown ROCOMPAT features");
2426                 return;
2427         }
2428
2429         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2430                 /* don't clear list on RO mount w/ errors */
2431                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2432                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2433                                   "clearing orphan list.\n");
2434                         es->s_last_orphan = 0;
2435                 }
2436                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2437                 return;
2438         }
2439
2440         if (s_flags & MS_RDONLY) {
2441                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2442                 sb->s_flags &= ~MS_RDONLY;
2443         }
2444 #ifdef CONFIG_QUOTA
2445         /* Needed for iput() to work correctly and not trash data */
2446         sb->s_flags |= MS_ACTIVE;
2447
2448         /*
2449          * Turn on quotas which were not enabled for read-only mounts if
2450          * filesystem has quota feature, so that they are updated correctly.
2451          */
2452         if (ext4_has_feature_quota(sb) && (s_flags & MS_RDONLY)) {
2453                 int ret = ext4_enable_quotas(sb);
2454
2455                 if (!ret)
2456                         quota_update = 1;
2457                 else
2458                         ext4_msg(sb, KERN_ERR,
2459                                 "Cannot turn on quotas: error %d", ret);
2460         }
2461
2462         /* Turn on journaled quotas used for old sytle */
2463         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2464                 if (EXT4_SB(sb)->s_qf_names[i]) {
2465                         int ret = ext4_quota_on_mount(sb, i);
2466
2467                         if (!ret)
2468                                 quota_update = 1;
2469                         else
2470                                 ext4_msg(sb, KERN_ERR,
2471                                         "Cannot turn on journaled "
2472                                         "quota: type %d: error %d", i, ret);
2473                 }
2474         }
2475 #endif
2476
2477         while (es->s_last_orphan) {
2478                 struct inode *inode;
2479
2480                 /*
2481                  * We may have encountered an error during cleanup; if
2482                  * so, skip the rest.
2483                  */
2484                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2485                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2486                         es->s_last_orphan = 0;
2487                         break;
2488                 }
2489
2490                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2491                 if (IS_ERR(inode)) {
2492                         es->s_last_orphan = 0;
2493                         break;
2494                 }
2495
2496                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2497                 dquot_initialize(inode);
2498                 if (inode->i_nlink) {
2499                         if (test_opt(sb, DEBUG))
2500                                 ext4_msg(sb, KERN_DEBUG,
2501                                         "%s: truncating inode %lu to %lld bytes",
2502                                         __func__, inode->i_ino, inode->i_size);
2503                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2504                                   inode->i_ino, inode->i_size);
2505                         inode_lock(inode);
2506                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2507                         ret = ext4_truncate(inode);
2508                         if (ret)
2509                                 ext4_std_error(inode->i_sb, ret);
2510                         inode_unlock(inode);
2511                         nr_truncates++;
2512                 } else {
2513                         if (test_opt(sb, DEBUG))
2514                                 ext4_msg(sb, KERN_DEBUG,
2515                                         "%s: deleting unreferenced inode %lu",
2516                                         __func__, inode->i_ino);
2517                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2518                                   inode->i_ino);
2519                         nr_orphans++;
2520                 }
2521                 iput(inode);  /* The delete magic happens here! */
2522         }
2523
2524 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2525
2526         if (nr_orphans)
2527                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2528                        PLURAL(nr_orphans));
2529         if (nr_truncates)
2530                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2531                        PLURAL(nr_truncates));
2532 #ifdef CONFIG_QUOTA
2533         /* Turn off quotas if they were enabled for orphan cleanup */
2534         if (quota_update) {
2535                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2536                         if (sb_dqopt(sb)->files[i])
2537                                 dquot_quota_off(sb, i);
2538                 }
2539         }
2540 #endif
2541         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2542 }
2543
2544 /*
2545  * Maximal extent format file size.
2546  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2547  * extent format containers, within a sector_t, and within i_blocks
2548  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2549  * so that won't be a limiting factor.
2550  *
2551  * However there is other limiting factor. We do store extents in the form
2552  * of starting block and length, hence the resulting length of the extent
2553  * covering maximum file size must fit into on-disk format containers as
2554  * well. Given that length is always by 1 unit bigger than max unit (because
2555  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2556  *
2557  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2558  */
2559 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2560 {
2561         loff_t res;
2562         loff_t upper_limit = MAX_LFS_FILESIZE;
2563
2564         /* small i_blocks in vfs inode? */
2565         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2566                 /*
2567                  * CONFIG_LBDAF is not enabled implies the inode
2568                  * i_block represent total blocks in 512 bytes
2569                  * 32 == size of vfs inode i_blocks * 8
2570                  */
2571                 upper_limit = (1LL << 32) - 1;
2572
2573                 /* total blocks in file system block size */
2574                 upper_limit >>= (blkbits - 9);
2575                 upper_limit <<= blkbits;
2576         }
2577
2578         /*
2579          * 32-bit extent-start container, ee_block. We lower the maxbytes
2580          * by one fs block, so ee_len can cover the extent of maximum file
2581          * size
2582          */
2583         res = (1LL << 32) - 1;
2584         res <<= blkbits;
2585
2586         /* Sanity check against vm- & vfs- imposed limits */
2587         if (res > upper_limit)
2588                 res = upper_limit;
2589
2590         return res;
2591 }
2592
2593 /*
2594  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2595  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2596  * We need to be 1 filesystem block less than the 2^48 sector limit.
2597  */
2598 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2599 {
2600         loff_t res = EXT4_NDIR_BLOCKS;
2601         int meta_blocks;
2602         loff_t upper_limit;
2603         /* This is calculated to be the largest file size for a dense, block
2604          * mapped file such that the file's total number of 512-byte sectors,
2605          * including data and all indirect blocks, does not exceed (2^48 - 1).
2606          *
2607          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2608          * number of 512-byte sectors of the file.
2609          */
2610
2611         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2612                 /*
2613                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2614                  * the inode i_block field represents total file blocks in
2615                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2616                  */
2617                 upper_limit = (1LL << 32) - 1;
2618
2619                 /* total blocks in file system block size */
2620                 upper_limit >>= (bits - 9);
2621
2622         } else {
2623                 /*
2624                  * We use 48 bit ext4_inode i_blocks
2625                  * With EXT4_HUGE_FILE_FL set the i_blocks
2626                  * represent total number of blocks in
2627                  * file system block size
2628                  */
2629                 upper_limit = (1LL << 48) - 1;
2630
2631         }
2632
2633         /* indirect blocks */
2634         meta_blocks = 1;
2635         /* double indirect blocks */
2636         meta_blocks += 1 + (1LL << (bits-2));
2637         /* tripple indirect blocks */
2638         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2639
2640         upper_limit -= meta_blocks;
2641         upper_limit <<= bits;
2642
2643         res += 1LL << (bits-2);
2644         res += 1LL << (2*(bits-2));
2645         res += 1LL << (3*(bits-2));
2646         res <<= bits;
2647         if (res > upper_limit)
2648                 res = upper_limit;
2649
2650         if (res > MAX_LFS_FILESIZE)
2651                 res = MAX_LFS_FILESIZE;
2652
2653         return res;
2654 }
2655
2656 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2657                                    ext4_fsblk_t logical_sb_block, int nr)
2658 {
2659         struct ext4_sb_info *sbi = EXT4_SB(sb);
2660         ext4_group_t bg, first_meta_bg;
2661         int has_super = 0;
2662
2663         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2664
2665         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2666                 return logical_sb_block + nr + 1;
2667         bg = sbi->s_desc_per_block * nr;
2668         if (ext4_bg_has_super(sb, bg))
2669                 has_super = 1;
2670
2671         /*
2672          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2673          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2674          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2675          * compensate.
2676          */
2677         if (sb->s_blocksize == 1024 && nr == 0 &&
2678             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2679                 has_super++;
2680
2681         return (has_super + ext4_group_first_block_no(sb, bg));
2682 }
2683
2684 /**
2685  * ext4_get_stripe_size: Get the stripe size.
2686  * @sbi: In memory super block info
2687  *
2688  * If we have specified it via mount option, then
2689  * use the mount option value. If the value specified at mount time is
2690  * greater than the blocks per group use the super block value.
2691  * If the super block value is greater than blocks per group return 0.
2692  * Allocator needs it be less than blocks per group.
2693  *
2694  */
2695 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2696 {
2697         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2698         unsigned long stripe_width =
2699                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2700         int ret;
2701
2702         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2703                 ret = sbi->s_stripe;
2704         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2705                 ret = stripe_width;
2706         else if (stride && stride <= sbi->s_blocks_per_group)
2707                 ret = stride;
2708         else
2709                 ret = 0;
2710
2711         /*
2712          * If the stripe width is 1, this makes no sense and
2713          * we set it to 0 to turn off stripe handling code.
2714          */
2715         if (ret <= 1)
2716                 ret = 0;
2717
2718         return ret;
2719 }
2720
2721 /*
2722  * Check whether this filesystem can be mounted based on
2723  * the features present and the RDONLY/RDWR mount requested.
2724  * Returns 1 if this filesystem can be mounted as requested,
2725  * 0 if it cannot be.
2726  */
2727 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2728 {
2729         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2730                 ext4_msg(sb, KERN_ERR,
2731                         "Couldn't mount because of "
2732                         "unsupported optional features (%x)",
2733                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2734                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2735                 return 0;
2736         }
2737
2738         if (readonly)
2739                 return 1;
2740
2741         if (ext4_has_feature_readonly(sb)) {
2742                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2743                 sb->s_flags |= MS_RDONLY;
2744                 return 1;
2745         }
2746
2747         /* Check that feature set is OK for a read-write mount */
2748         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2749                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2750                          "unsupported optional features (%x)",
2751                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2752                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2753                 return 0;
2754         }
2755         /*
2756          * Large file size enabled file system can only be mounted
2757          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2758          */
2759         if (ext4_has_feature_huge_file(sb)) {
2760                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2761                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2762                                  "cannot be mounted RDWR without "
2763                                  "CONFIG_LBDAF");
2764                         return 0;
2765                 }
2766         }
2767         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2768                 ext4_msg(sb, KERN_ERR,
2769                          "Can't support bigalloc feature without "
2770                          "extents feature\n");
2771                 return 0;
2772         }
2773
2774 #ifndef CONFIG_QUOTA
2775         if (ext4_has_feature_quota(sb) && !readonly) {
2776                 ext4_msg(sb, KERN_ERR,
2777                          "Filesystem with quota feature cannot be mounted RDWR "
2778                          "without CONFIG_QUOTA");
2779                 return 0;
2780         }
2781         if (ext4_has_feature_project(sb) && !readonly) {
2782                 ext4_msg(sb, KERN_ERR,
2783                          "Filesystem with project quota feature cannot be mounted RDWR "
2784                          "without CONFIG_QUOTA");
2785                 return 0;
2786         }
2787 #endif  /* CONFIG_QUOTA */
2788         return 1;
2789 }
2790
2791 /*
2792  * This function is called once a day if we have errors logged
2793  * on the file system
2794  */
2795 static void print_daily_error_info(unsigned long arg)
2796 {
2797         struct super_block *sb = (struct super_block *) arg;
2798         struct ext4_sb_info *sbi;
2799         struct ext4_super_block *es;
2800
2801         sbi = EXT4_SB(sb);
2802         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 = EXT4_SB(sb)->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 ||
3140             (sb->s_flags & MS_RDONLY) ||
3141             !test_opt(sb, INIT_INODE_TABLE))
3142                 goto out;
3143
3144         elr = ext4_li_request_new(sb, first_not_zeroed);
3145         if (!elr) {
3146                 ret = -ENOMEM;
3147                 goto out;
3148         }
3149
3150         if (NULL == ext4_li_info) {
3151                 ret = ext4_li_info_new();
3152                 if (ret)
3153                         goto out;
3154         }
3155
3156         mutex_lock(&ext4_li_info->li_list_mtx);
3157         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3158         mutex_unlock(&ext4_li_info->li_list_mtx);
3159
3160         sbi->s_li_request = elr;
3161         /*
3162          * set elr to NULL here since it has been inserted to
3163          * the request_list and the removal and free of it is
3164          * handled by ext4_clear_request_list from now on.
3165          */
3166         elr = NULL;
3167
3168         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3169                 ret = ext4_run_lazyinit_thread();
3170                 if (ret)
3171                         goto out;
3172         }
3173 out:
3174         mutex_unlock(&ext4_li_mtx);
3175         if (ret)
3176                 kfree(elr);
3177         return ret;
3178 }
3179
3180 /*
3181  * We do not need to lock anything since this is called on
3182  * module unload.
3183  */
3184 static void ext4_destroy_lazyinit_thread(void)
3185 {
3186         /*
3187          * If thread exited earlier
3188          * there's nothing to be done.
3189          */
3190         if (!ext4_li_info || !ext4_lazyinit_task)
3191                 return;
3192
3193         kthread_stop(ext4_lazyinit_task);
3194 }
3195
3196 static int set_journal_csum_feature_set(struct super_block *sb)
3197 {
3198         int ret = 1;
3199         int compat, incompat;
3200         struct ext4_sb_info *sbi = EXT4_SB(sb);
3201
3202         if (ext4_has_metadata_csum(sb)) {
3203                 /* journal checksum v3 */
3204                 compat = 0;
3205                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3206         } else {
3207                 /* journal checksum v1 */
3208                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3209                 incompat = 0;
3210         }
3211
3212         jbd2_journal_clear_features(sbi->s_journal,
3213                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3214                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3215                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3216         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3217                 ret = jbd2_journal_set_features(sbi->s_journal,
3218                                 compat, 0,
3219                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3220                                 incompat);
3221         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3222                 ret = jbd2_journal_set_features(sbi->s_journal,
3223                                 compat, 0,
3224                                 incompat);
3225                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3226                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3227         } else {
3228                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3229                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3230         }
3231
3232         return ret;
3233 }
3234
3235 /*
3236  * Note: calculating the overhead so we can be compatible with
3237  * historical BSD practice is quite difficult in the face of
3238  * clusters/bigalloc.  This is because multiple metadata blocks from
3239  * different block group can end up in the same allocation cluster.
3240  * Calculating the exact overhead in the face of clustered allocation
3241  * requires either O(all block bitmaps) in memory or O(number of block
3242  * groups**2) in time.  We will still calculate the superblock for
3243  * older file systems --- and if we come across with a bigalloc file
3244  * system with zero in s_overhead_clusters the estimate will be close to
3245  * correct especially for very large cluster sizes --- but for newer
3246  * file systems, it's better to calculate this figure once at mkfs
3247  * time, and store it in the superblock.  If the superblock value is
3248  * present (even for non-bigalloc file systems), we will use it.
3249  */
3250 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3251                           char *buf)
3252 {
3253         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3254         struct ext4_group_desc  *gdp;
3255         ext4_fsblk_t            first_block, last_block, b;
3256         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3257         int                     s, j, count = 0;
3258
3259         if (!ext4_has_feature_bigalloc(sb))
3260                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3261                         sbi->s_itb_per_group + 2);
3262
3263         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3264                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3265         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3266         for (i = 0; i < ngroups; i++) {
3267                 gdp = ext4_get_group_desc(sb, i, NULL);
3268                 b = ext4_block_bitmap(sb, gdp);
3269                 if (b >= first_block && b <= last_block) {
3270                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3271                         count++;
3272                 }
3273                 b = ext4_inode_bitmap(sb, gdp);
3274                 if (b >= first_block && b <= last_block) {
3275                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3276                         count++;
3277                 }
3278                 b = ext4_inode_table(sb, gdp);
3279                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3280                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3281                                 int c = EXT4_B2C(sbi, b - first_block);
3282                                 ext4_set_bit(c, buf);
3283                                 count++;
3284                         }
3285                 if (i != grp)
3286                         continue;
3287                 s = 0;
3288                 if (ext4_bg_has_super(sb, grp)) {
3289                         ext4_set_bit(s++, buf);
3290                         count++;
3291                 }
3292                 j = ext4_bg_num_gdb(sb, grp);
3293                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3294                         ext4_error(sb, "Invalid number of block group "
3295                                    "descriptor blocks: %d", j);
3296                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3297                 }
3298                 count += j;
3299                 for (; j > 0; j--)
3300                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3301         }
3302         if (!count)
3303                 return 0;
3304         return EXT4_CLUSTERS_PER_GROUP(sb) -
3305                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3306 }
3307
3308 /*
3309  * Compute the overhead and stash it in sbi->s_overhead
3310  */
3311 int ext4_calculate_overhead(struct super_block *sb)
3312 {
3313         struct ext4_sb_info *sbi = EXT4_SB(sb);
3314         struct ext4_super_block *es = sbi->s_es;
3315         struct inode *j_inode;
3316         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3317         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3318         ext4_fsblk_t overhead = 0;
3319         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3320
3321         if (!buf)
3322                 return -ENOMEM;
3323
3324         /*
3325          * Compute the overhead (FS structures).  This is constant
3326          * for a given filesystem unless the number of block groups
3327          * changes so we cache the previous value until it does.
3328          */
3329
3330         /*
3331          * All of the blocks before first_data_block are overhead
3332          */
3333         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3334
3335         /*
3336          * Add the overhead found in each block group
3337          */
3338         for (i = 0; i < ngroups; i++) {
3339                 int blks;
3340
3341                 blks = count_overhead(sb, i, buf);
3342                 overhead += blks;
3343                 if (blks)
3344                         memset(buf, 0, PAGE_SIZE);
3345                 cond_resched();
3346         }
3347
3348         /*
3349          * Add the internal journal blocks whether the journal has been
3350          * loaded or not
3351          */
3352         if (sbi->s_journal && !sbi->journal_bdev)
3353                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3354         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3355                 j_inode = ext4_get_journal_inode(sb, j_inum);
3356                 if (j_inode) {
3357                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3358                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3359                         iput(j_inode);
3360                 } else {
3361                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3362                 }
3363         }
3364         sbi->s_overhead = overhead;
3365         smp_wmb();
3366         free_page((unsigned long) buf);
3367         return 0;
3368 }
3369
3370 static void ext4_set_resv_clusters(struct super_block *sb)
3371 {
3372         ext4_fsblk_t resv_clusters;
3373         struct ext4_sb_info *sbi = EXT4_SB(sb);
3374
3375         /*
3376          * There's no need to reserve anything when we aren't using extents.
3377          * The space estimates are exact, there are no unwritten extents,
3378          * hole punching doesn't need new metadata... This is needed especially
3379          * to keep ext2/3 backward compatibility.
3380          */
3381         if (!ext4_has_feature_extents(sb))
3382                 return;
3383         /*
3384          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3385          * This should cover the situations where we can not afford to run
3386          * out of space like for example punch hole, or converting
3387          * unwritten extents in delalloc path. In most cases such
3388          * allocation would require 1, or 2 blocks, higher numbers are
3389          * very rare.
3390          */
3391         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3392                          sbi->s_cluster_bits);
3393
3394         do_div(resv_clusters, 50);
3395         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3396
3397         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3398 }
3399
3400 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3401 {
3402         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3403         char *orig_data = kstrdup(data, GFP_KERNEL);
3404         struct buffer_head *bh;
3405         struct ext4_super_block *es = NULL;
3406         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3407         ext4_fsblk_t block;
3408         ext4_fsblk_t sb_block = get_sb_block(&data);
3409         ext4_fsblk_t logical_sb_block;
3410         unsigned long offset = 0;
3411         unsigned long journal_devnum = 0;
3412         unsigned long def_mount_opts;
3413         struct inode *root;
3414         const char *descr;
3415         int ret = -ENOMEM;
3416         int blocksize, clustersize;
3417         unsigned int db_count;
3418         unsigned int i;
3419         int needs_recovery, has_huge_files, has_bigalloc;
3420         __u64 blocks_count;
3421         int err = 0;
3422         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3423         ext4_group_t first_not_zeroed;
3424
3425         if ((data && !orig_data) || !sbi)
3426                 goto out_free_base;
3427
3428         sbi->s_daxdev = dax_dev;
3429         sbi->s_blockgroup_lock =
3430                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3431         if (!sbi->s_blockgroup_lock)
3432                 goto out_free_base;
3433
3434         sb->s_fs_info = sbi;
3435         sbi->s_sb = sb;
3436         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3437         sbi->s_sb_block = sb_block;
3438         if (sb->s_bdev->bd_part)
3439                 sbi->s_sectors_written_start =
3440                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3441
3442         /* Cleanup superblock name */
3443         strreplace(sb->s_id, '/', '!');
3444
3445         /* -EINVAL is default */
3446         ret = -EINVAL;
3447         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3448         if (!blocksize) {
3449                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3450                 goto out_fail;
3451         }
3452
3453         /*
3454          * The ext4 superblock will not be buffer aligned for other than 1kB
3455          * block sizes.  We need to calculate the offset from buffer start.
3456          */
3457         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3458                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3459                 offset = do_div(logical_sb_block, blocksize);
3460         } else {
3461                 logical_sb_block = sb_block;
3462         }
3463
3464         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3465                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3466                 goto out_fail;
3467         }
3468         /*
3469          * Note: s_es must be initialized as soon as possible because
3470          *       some ext4 macro-instructions depend on its value
3471          */
3472         es = (struct ext4_super_block *) (bh->b_data + offset);
3473         sbi->s_es = es;
3474         sb->s_magic = le16_to_cpu(es->s_magic);
3475         if (sb->s_magic != EXT4_SUPER_MAGIC)
3476                 goto cantfind_ext4;
3477         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3478
3479         /* Warn if metadata_csum and gdt_csum are both set. */
3480         if (ext4_has_feature_metadata_csum(sb) &&
3481             ext4_has_feature_gdt_csum(sb))
3482                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3483                              "redundant flags; please run fsck.");
3484
3485         /* Check for a known checksum algorithm */
3486         if (!ext4_verify_csum_type(sb, es)) {
3487                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3488                          "unknown checksum algorithm.");
3489                 silent = 1;
3490                 goto cantfind_ext4;
3491         }
3492
3493         /* Load the checksum driver */
3494         if (ext4_has_feature_metadata_csum(sb) ||
3495             ext4_has_feature_ea_inode(sb)) {
3496                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3497                 if (IS_ERR(sbi->s_chksum_driver)) {
3498                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3499                         ret = PTR_ERR(sbi->s_chksum_driver);
3500                         sbi->s_chksum_driver = NULL;
3501                         goto failed_mount;
3502                 }
3503         }
3504
3505         /* Check superblock checksum */
3506         if (!ext4_superblock_csum_verify(sb, es)) {
3507                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3508                          "invalid superblock checksum.  Run e2fsck?");
3509                 silent = 1;
3510                 ret = -EFSBADCRC;
3511                 goto cantfind_ext4;
3512         }
3513
3514         /* Precompute checksum seed for all metadata */
3515         if (ext4_has_feature_csum_seed(sb))
3516                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3517         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3518                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3519                                                sizeof(es->s_uuid));
3520
3521         /* Set defaults before we parse the mount options */
3522         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3523         set_opt(sb, INIT_INODE_TABLE);
3524         if (def_mount_opts & EXT4_DEFM_DEBUG)
3525                 set_opt(sb, DEBUG);
3526         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3527                 set_opt(sb, GRPID);
3528         if (def_mount_opts & EXT4_DEFM_UID16)
3529                 set_opt(sb, NO_UID32);
3530         /* xattr user namespace & acls are now defaulted on */
3531         set_opt(sb, XATTR_USER);
3532 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3533         set_opt(sb, POSIX_ACL);
3534 #endif
3535         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3536         if (ext4_has_metadata_csum(sb))
3537                 set_opt(sb, JOURNAL_CHECKSUM);
3538
3539         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3540                 set_opt(sb, JOURNAL_DATA);
3541         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3542                 set_opt(sb, ORDERED_DATA);
3543         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3544                 set_opt(sb, WRITEBACK_DATA);
3545
3546         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3547                 set_opt(sb, ERRORS_PANIC);
3548         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3549                 set_opt(sb, ERRORS_CONT);
3550         else
3551                 set_opt(sb, ERRORS_RO);
3552         /* block_validity enabled by default; disable with noblock_validity */
3553         set_opt(sb, BLOCK_VALIDITY);
3554         if (def_mount_opts & EXT4_DEFM_DISCARD)
3555                 set_opt(sb, DISCARD);
3556
3557         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3558         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3559         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3560         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3561         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3562
3563         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3564                 set_opt(sb, BARRIER);
3565
3566         /*
3567          * enable delayed allocation by default
3568          * Use -o nodelalloc to turn it off
3569          */
3570         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3571             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3572                 set_opt(sb, DELALLOC);
3573
3574         /*
3575          * set default s_li_wait_mult for lazyinit, for the case there is
3576          * no mount option specified.
3577          */
3578         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3579
3580         if (sbi->s_es->s_mount_opts[0]) {
3581                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3582                                               sizeof(sbi->s_es->s_mount_opts),
3583                                               GFP_KERNEL);
3584                 if (!s_mount_opts)
3585                         goto failed_mount;
3586                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3587                                    &journal_ioprio, 0)) {
3588                         ext4_msg(sb, KERN_WARNING,
3589                                  "failed to parse options in superblock: %s",
3590                                  s_mount_opts);
3591                 }
3592                 kfree(s_mount_opts);
3593         }
3594         sbi->s_def_mount_opt = sbi->s_mount_opt;
3595         if (!parse_options((char *) data, sb, &journal_devnum,
3596                            &journal_ioprio, 0))
3597                 goto failed_mount;
3598
3599         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3600                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3601                             "with data=journal disables delayed "
3602                             "allocation and O_DIRECT support!\n");
3603                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3604                         ext4_msg(sb, KERN_ERR, "can't mount with "
3605                                  "both data=journal and delalloc");
3606                         goto failed_mount;
3607                 }
3608                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3609                         ext4_msg(sb, KERN_ERR, "can't mount with "
3610                                  "both data=journal and dioread_nolock");
3611                         goto failed_mount;
3612                 }
3613                 if (test_opt(sb, DAX)) {
3614                         ext4_msg(sb, KERN_ERR, "can't mount with "
3615                                  "both data=journal and dax");
3616                         goto failed_mount;
3617                 }
3618                 if (ext4_has_feature_encrypt(sb)) {
3619                         ext4_msg(sb, KERN_WARNING,
3620                                  "encrypted files will use data=ordered "
3621                                  "instead of data journaling mode");
3622                 }
3623                 if (test_opt(sb, DELALLOC))
3624                         clear_opt(sb, DELALLOC);
3625         } else {
3626                 sb->s_iflags |= SB_I_CGROUPWB;
3627         }
3628
3629         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3630                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3631
3632         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3633             (ext4_has_compat_features(sb) ||
3634              ext4_has_ro_compat_features(sb) ||
3635              ext4_has_incompat_features(sb)))
3636                 ext4_msg(sb, KERN_WARNING,
3637                        "feature flags set on rev 0 fs, "
3638                        "running e2fsck is recommended");
3639
3640         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3641                 set_opt2(sb, HURD_COMPAT);
3642                 if (ext4_has_feature_64bit(sb)) {
3643                         ext4_msg(sb, KERN_ERR,
3644                                  "The Hurd can't support 64-bit file systems");
3645                         goto failed_mount;
3646                 }
3647
3648                 /*
3649                  * ea_inode feature uses l_i_version field which is not
3650                  * available in HURD_COMPAT mode.
3651                  */
3652                 if (ext4_has_feature_ea_inode(sb)) {
3653                         ext4_msg(sb, KERN_ERR,
3654                                  "ea_inode feature is not supported for Hurd");
3655                         goto failed_mount;
3656                 }
3657         }
3658
3659         if (IS_EXT2_SB(sb)) {
3660                 if (ext2_feature_set_ok(sb))
3661                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3662                                  "using the ext4 subsystem");
3663                 else {
3664                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3665                                  "to feature incompatibilities");
3666                         goto failed_mount;
3667                 }
3668         }
3669
3670         if (IS_EXT3_SB(sb)) {
3671                 if (ext3_feature_set_ok(sb))
3672                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3673                                  "using the ext4 subsystem");
3674                 else {
3675                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3676                                  "to feature incompatibilities");
3677                         goto failed_mount;
3678                 }
3679         }
3680
3681         /*
3682          * Check feature flags regardless of the revision level, since we
3683          * previously didn't change the revision level when setting the flags,
3684          * so there is a chance incompat flags are set on a rev 0 filesystem.
3685          */
3686         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3687                 goto failed_mount;
3688
3689         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3690         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3691             blocksize > EXT4_MAX_BLOCK_SIZE) {
3692                 ext4_msg(sb, KERN_ERR,
3693                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3694                          blocksize, le32_to_cpu(es->s_log_block_size));
3695                 goto failed_mount;
3696         }
3697         if (le32_to_cpu(es->s_log_block_size) >
3698             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3699                 ext4_msg(sb, KERN_ERR,
3700                          "Invalid log block size: %u",
3701                          le32_to_cpu(es->s_log_block_size));
3702                 goto failed_mount;
3703         }
3704
3705         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3706                 ext4_msg(sb, KERN_ERR,
3707                          "Number of reserved GDT blocks insanely large: %d",
3708                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3709                 goto failed_mount;
3710         }
3711
3712         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3713                 err = bdev_dax_supported(sb, blocksize);
3714                 if (err)
3715                         goto failed_mount;
3716         }
3717
3718         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3719                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3720                          es->s_encryption_level);
3721                 goto failed_mount;
3722         }
3723
3724         if (sb->s_blocksize != blocksize) {
3725                 /* Validate the filesystem blocksize */
3726                 if (!sb_set_blocksize(sb, blocksize)) {
3727                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3728                                         blocksize);
3729                         goto failed_mount;
3730                 }
3731
3732                 brelse(bh);
3733                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3734                 offset = do_div(logical_sb_block, blocksize);
3735                 bh = sb_bread_unmovable(sb, logical_sb_block);
3736                 if (!bh) {
3737                         ext4_msg(sb, KERN_ERR,
3738                                "Can't read superblock on 2nd try");
3739                         goto failed_mount;
3740                 }
3741                 es = (struct ext4_super_block *)(bh->b_data + offset);
3742                 sbi->s_es = es;
3743                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3744                         ext4_msg(sb, KERN_ERR,
3745                                "Magic mismatch, very weird!");
3746                         goto failed_mount;
3747                 }
3748         }
3749
3750         has_huge_files = ext4_has_feature_huge_file(sb);
3751         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3752                                                       has_huge_files);
3753         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3754
3755         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3756                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3757                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3758         } else {
3759                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3760                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3761                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3762                     (!is_power_of_2(sbi->s_inode_size)) ||
3763                     (sbi->s_inode_size > blocksize)) {
3764                         ext4_msg(sb, KERN_ERR,
3765                                "unsupported inode size: %d",
3766                                sbi->s_inode_size);
3767                         goto failed_mount;
3768                 }
3769                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3770                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3771         }
3772
3773         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3774         if (ext4_has_feature_64bit(sb)) {
3775                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3776                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3777                     !is_power_of_2(sbi->s_desc_size)) {
3778                         ext4_msg(sb, KERN_ERR,
3779                                "unsupported descriptor size %lu",
3780                                sbi->s_desc_size);
3781                         goto failed_mount;
3782                 }
3783         } else
3784                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3785
3786         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3787         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3788
3789         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3790         if (sbi->s_inodes_per_block == 0)
3791                 goto cantfind_ext4;
3792         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
3793             sbi->s_inodes_per_group > blocksize * 8) {
3794                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
3795                          sbi->s_blocks_per_group);
3796                 goto failed_mount;
3797         }
3798         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3799                                         sbi->s_inodes_per_block;
3800         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3801         sbi->s_sbh = bh;
3802         sbi->s_mount_state = le16_to_cpu(es->s_state);
3803         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3804         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3805
3806         for (i = 0; i < 4; i++)
3807                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3808         sbi->s_def_hash_version = es->s_def_hash_version;
3809         if (ext4_has_feature_dir_index(sb)) {
3810                 i = le32_to_cpu(es->s_flags);
3811                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3812                         sbi->s_hash_unsigned = 3;
3813                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3814 #ifdef __CHAR_UNSIGNED__
3815                         if (!(sb->s_flags & MS_RDONLY))
3816                                 es->s_flags |=
3817                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3818                         sbi->s_hash_unsigned = 3;
3819 #else
3820                         if (!(sb->s_flags & MS_RDONLY))
3821                                 es->s_flags |=
3822                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3823 #endif
3824                 }
3825         }
3826
3827         /* Handle clustersize */
3828         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3829         has_bigalloc = ext4_has_feature_bigalloc(sb);
3830         if (has_bigalloc) {
3831                 if (clustersize < blocksize) {
3832                         ext4_msg(sb, KERN_ERR,
3833                                  "cluster size (%d) smaller than "
3834                                  "block size (%d)", clustersize, blocksize);
3835                         goto failed_mount;
3836                 }
3837                 if (le32_to_cpu(es->s_log_cluster_size) >
3838                     (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3839                         ext4_msg(sb, KERN_ERR,
3840                                  "Invalid log cluster size: %u",
3841                                  le32_to_cpu(es->s_log_cluster_size));
3842                         goto failed_mount;
3843                 }
3844                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3845                         le32_to_cpu(es->s_log_block_size);
3846                 sbi->s_clusters_per_group =
3847                         le32_to_cpu(es->s_clusters_per_group);
3848                 if (sbi->s_clusters_per_group > blocksize * 8) {
3849                         ext4_msg(sb, KERN_ERR,
3850                                  "#clusters per group too big: %lu",
3851                                  sbi->s_clusters_per_group);
3852                         goto failed_mount;
3853                 }
3854                 if (sbi->s_blocks_per_group !=
3855                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3856                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3857                                  "clusters per group (%lu) inconsistent",
3858                                  sbi->s_blocks_per_group,
3859                                  sbi->s_clusters_per_group);
3860                         goto failed_mount;
3861                 }
3862         } else {
3863                 if (clustersize != blocksize) {
3864                         ext4_warning(sb, "fragment/cluster size (%d) != "
3865                                      "block size (%d)", clustersize,
3866                                      blocksize);
3867                         clustersize = blocksize;
3868                 }
3869                 if (sbi->s_blocks_per_group > blocksize * 8) {
3870                         ext4_msg(sb, KERN_ERR,
3871                                  "#blocks per group too big: %lu",
3872                                  sbi->s_blocks_per_group);
3873                         goto failed_mount;
3874                 }
3875                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3876                 sbi->s_cluster_bits = 0;
3877         }
3878         sbi->s_cluster_ratio = clustersize / blocksize;
3879
3880         /* Do we have standard group size of clustersize * 8 blocks ? */
3881         if (sbi->s_blocks_per_group == clustersize << 3)
3882                 set_opt2(sb, STD_GROUP_SIZE);
3883
3884         /*
3885          * Test whether we have more sectors than will fit in sector_t,
3886          * and whether the max offset is addressable by the page cache.
3887          */
3888         err = generic_check_addressable(sb->s_blocksize_bits,
3889                                         ext4_blocks_count(es));
3890         if (err) {
3891                 ext4_msg(sb, KERN_ERR, "filesystem"
3892                          " too large to mount safely on this system");
3893                 if (sizeof(sector_t) < 8)
3894                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3895                 goto failed_mount;
3896         }
3897
3898         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3899                 goto cantfind_ext4;
3900
3901         /* check blocks count against device size */
3902         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3903         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3904                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3905                        "exceeds size of device (%llu blocks)",
3906                        ext4_blocks_count(es), blocks_count);
3907                 goto failed_mount;
3908         }
3909
3910         /*
3911          * It makes no sense for the first data block to be beyond the end
3912          * of the filesystem.
3913          */
3914         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3915                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3916                          "block %u is beyond end of filesystem (%llu)",
3917                          le32_to_cpu(es->s_first_data_block),
3918                          ext4_blocks_count(es));
3919                 goto failed_mount;
3920         }
3921         blocks_count = (ext4_blocks_count(es) -
3922                         le32_to_cpu(es->s_first_data_block) +
3923                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3924         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3925         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3926                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3927                        "(block count %llu, first data block %u, "
3928                        "blocks per group %lu)", sbi->s_groups_count,
3929                        ext4_blocks_count(es),
3930                        le32_to_cpu(es->s_first_data_block),
3931                        EXT4_BLOCKS_PER_GROUP(sb));
3932                 goto failed_mount;
3933         }
3934         sbi->s_groups_count = blocks_count;
3935         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3936                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3937         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3938                    EXT4_DESC_PER_BLOCK(sb);
3939         if (ext4_has_feature_meta_bg(sb)) {
3940                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
3941                         ext4_msg(sb, KERN_WARNING,
3942                                  "first meta block group too large: %u "
3943                                  "(group descriptor block count %u)",
3944                                  le32_to_cpu(es->s_first_meta_bg), db_count);
3945                         goto failed_mount;
3946                 }
3947         }
3948         sbi->s_group_desc = kvmalloc(db_count *
3949                                           sizeof(struct buffer_head *),
3950                                           GFP_KERNEL);
3951         if (sbi->s_group_desc == NULL) {
3952                 ext4_msg(sb, KERN_ERR, "not enough memory");
3953                 ret = -ENOMEM;
3954                 goto failed_mount;
3955         }
3956
3957         bgl_lock_init(sbi->s_blockgroup_lock);
3958
3959         /* Pre-read the descriptors into the buffer cache */
3960         for (i = 0; i < db_count; i++) {
3961                 block = descriptor_loc(sb, logical_sb_block, i);
3962                 sb_breadahead(sb, block);
3963         }
3964
3965         for (i = 0; i < db_count; i++) {
3966                 block = descriptor_loc(sb, logical_sb_block, i);
3967                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
3968                 if (!sbi->s_group_desc[i]) {
3969                         ext4_msg(sb, KERN_ERR,
3970                                "can't read group descriptor %d", i);
3971                         db_count = i;
3972                         goto failed_mount2;
3973                 }
3974         }
3975         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
3976                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3977                 ret = -EFSCORRUPTED;
3978                 goto failed_mount2;
3979         }
3980
3981         sbi->s_gdb_count = db_count;
3982         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3983         spin_lock_init(&sbi->s_next_gen_lock);
3984
3985         setup_timer(&sbi->s_err_report, print_daily_error_info,
3986                 (unsigned long) sb);
3987
3988         /* Register extent status tree shrinker */
3989         if (ext4_es_register_shrinker(sbi))
3990                 goto failed_mount3;
3991
3992         sbi->s_stripe = ext4_get_stripe_size(sbi);
3993         sbi->s_extent_max_zeroout_kb = 32;
3994
3995         /*
3996          * set up enough so that it can read an inode
3997          */
3998         sb->s_op = &ext4_sops;
3999         sb->s_export_op = &ext4_export_ops;
4000         sb->s_xattr = ext4_xattr_handlers;
4001         sb->s_cop = &ext4_cryptops;
4002 #ifdef CONFIG_QUOTA
4003         sb->dq_op = &ext4_quota_operations;
4004         if (ext4_has_feature_quota(sb))
4005                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4006         else
4007                 sb->s_qcop = &ext4_qctl_operations;
4008         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4009 #endif
4010         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4011
4012         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4013         mutex_init(&sbi->s_orphan_lock);
4014
4015         sb->s_root = NULL;
4016
4017         needs_recovery = (es->s_last_orphan != 0 ||
4018                           ext4_has_feature_journal_needs_recovery(sb));
4019
4020         if (ext4_has_feature_mmp(sb) && !(sb->s_flags & MS_RDONLY))
4021                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4022                         goto failed_mount3a;
4023
4024         /*
4025          * The first inode we look at is the journal inode.  Don't try
4026          * root first: it may be modified in the journal!
4027          */
4028         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4029                 err = ext4_load_journal(sb, es, journal_devnum);
4030                 if (err)
4031                         goto failed_mount3a;
4032         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
4033                    ext4_has_feature_journal_needs_recovery(sb)) {
4034                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4035                        "suppressed and not mounted read-only");
4036                 goto failed_mount_wq;
4037         } else {
4038                 /* Nojournal mode, all journal mount options are illegal */
4039                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4040                         ext4_msg(sb, KERN_ERR, "can't mount with "
4041                                  "journal_checksum, fs mounted w/o journal");
4042                         goto failed_mount_wq;
4043                 }
4044                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4045                         ext4_msg(sb, KERN_ERR, "can't mount with "
4046                                  "journal_async_commit, fs mounted w/o journal");
4047                         goto failed_mount_wq;
4048                 }
4049                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4050                         ext4_msg(sb, KERN_ERR, "can't mount with "
4051                                  "commit=%lu, fs mounted w/o journal",
4052                                  sbi->s_commit_interval / HZ);
4053                         goto failed_mount_wq;
4054                 }
4055                 if (EXT4_MOUNT_DATA_FLAGS &
4056                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4057                         ext4_msg(sb, KERN_ERR, "can't mount with "
4058                                  "data=, fs mounted w/o journal");
4059                         goto failed_mount_wq;
4060                 }
4061                 sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
4062                 clear_opt(sb, JOURNAL_CHECKSUM);
4063                 clear_opt(sb, DATA_FLAGS);
4064                 sbi->s_journal = NULL;
4065                 needs_recovery = 0;
4066                 goto no_journal;
4067         }
4068
4069         if (ext4_has_feature_64bit(sb) &&
4070             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4071                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4072                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4073                 goto failed_mount_wq;
4074         }
4075
4076         if (!set_journal_csum_feature_set(sb)) {
4077                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4078                          "feature set");
4079                 goto failed_mount_wq;
4080         }
4081
4082         /* We have now updated the journal if required, so we can
4083          * validate the data journaling mode. */
4084         switch (test_opt(sb, DATA_FLAGS)) {
4085         case 0:
4086                 /* No mode set, assume a default based on the journal
4087                  * capabilities: ORDERED_DATA if the journal can
4088                  * cope, else JOURNAL_DATA
4089                  */
4090                 if (jbd2_journal_check_available_features
4091                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4092                         set_opt(sb, ORDERED_DATA);
4093                 else
4094                         set_opt(sb, JOURNAL_DATA);
4095                 break;
4096
4097         case EXT4_MOUNT_ORDERED_DATA:
4098         case EXT4_MOUNT_WRITEBACK_DATA:
4099                 if (!jbd2_journal_check_available_features
4100                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4101                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4102                                "requested data journaling mode");
4103                         goto failed_mount_wq;
4104                 }
4105         default:
4106                 break;
4107         }
4108
4109         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4110             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4111                 ext4_msg(sb, KERN_ERR, "can't mount with "
4112                         "journal_async_commit in data=ordered mode");
4113                 goto failed_mount_wq;
4114         }
4115
4116         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4117
4118         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4119
4120 no_journal:
4121         if (!test_opt(sb, NO_MBCACHE)) {
4122                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4123                 if (!sbi->s_ea_block_cache) {
4124                         ext4_msg(sb, KERN_ERR,
4125                                  "Failed to create ea_block_cache");
4126                         goto failed_mount_wq;
4127                 }
4128
4129                 if (ext4_has_feature_ea_inode(sb)) {
4130                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4131                         if (!sbi->s_ea_inode_cache) {
4132                                 ext4_msg(sb, KERN_ERR,
4133                                          "Failed to create ea_inode_cache");
4134                                 goto failed_mount_wq;
4135                         }
4136                 }
4137         }
4138
4139         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4140             (blocksize != PAGE_SIZE)) {
4141                 ext4_msg(sb, KERN_ERR,
4142                          "Unsupported blocksize for fs encryption");
4143                 goto failed_mount_wq;
4144         }
4145
4146         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !(sb->s_flags & MS_RDONLY) &&
4147             !ext4_has_feature_encrypt(sb)) {
4148                 ext4_set_feature_encrypt(sb);
4149                 ext4_commit_super(sb, 1);
4150         }
4151
4152         /*
4153          * Get the # of file system overhead blocks from the
4154          * superblock if present.
4155          */
4156         if (es->s_overhead_clusters)
4157                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4158         else {
4159                 err = ext4_calculate_overhead(sb);
4160                 if (err)
4161                         goto failed_mount_wq;
4162         }
4163
4164         /*
4165          * The maximum number of concurrent works can be high and
4166          * concurrency isn't really necessary.  Limit it to 1.
4167          */
4168         EXT4_SB(sb)->rsv_conversion_wq =
4169                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4170         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4171                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4172                 ret = -ENOMEM;
4173                 goto failed_mount4;
4174         }
4175
4176         /*
4177          * The jbd2_journal_load will have done any necessary log recovery,
4178          * so we can safely mount the rest of the filesystem now.
4179          */
4180
4181         root = ext4_iget(sb, EXT4_ROOT_INO);
4182         if (IS_ERR(root)) {
4183                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4184                 ret = PTR_ERR(root);
4185                 root = NULL;
4186                 goto failed_mount4;
4187         }
4188         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4189                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4190                 iput(root);
4191                 goto failed_mount4;
4192         }
4193         sb->s_root = d_make_root(root);
4194         if (!sb->s_root) {
4195                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4196                 ret = -ENOMEM;
4197                 goto failed_mount4;
4198         }
4199
4200         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
4201                 sb->s_flags |= MS_RDONLY;
4202
4203         /* determine the minimum size of new large inodes, if present */
4204         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE &&
4205             sbi->s_want_extra_isize == 0) {
4206                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4207                                                      EXT4_GOOD_OLD_INODE_SIZE;
4208                 if (ext4_has_feature_extra_isize(sb)) {
4209                         if (sbi->s_want_extra_isize <
4210                             le16_to_cpu(es->s_want_extra_isize))
4211                                 sbi->s_want_extra_isize =
4212                                         le16_to_cpu(es->s_want_extra_isize);
4213                         if (sbi->s_want_extra_isize <
4214                             le16_to_cpu(es->s_min_extra_isize))
4215                                 sbi->s_want_extra_isize =
4216                                         le16_to_cpu(es->s_min_extra_isize);
4217                 }
4218         }
4219         /* Check if enough inode space is available */
4220         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
4221                                                         sbi->s_inode_size) {
4222                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4223                                                        EXT4_GOOD_OLD_INODE_SIZE;
4224                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
4225                          "available");
4226         }
4227
4228         ext4_set_resv_clusters(sb);
4229
4230         err = ext4_setup_system_zone(sb);
4231         if (err) {
4232                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4233                          "zone (%d)", err);
4234                 goto failed_mount4a;
4235         }
4236
4237         ext4_ext_init(sb);
4238         err = ext4_mb_init(sb);
4239         if (err) {
4240                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4241                          err);
4242                 goto failed_mount5;
4243         }
4244
4245         block = ext4_count_free_clusters(sb);
4246         ext4_free_blocks_count_set(sbi->s_es,
4247                                    EXT4_C2B(sbi, block));
4248         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4249                                   GFP_KERNEL);
4250         if (!err) {
4251                 unsigned long freei = ext4_count_free_inodes(sb);
4252                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4253                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4254                                           GFP_KERNEL);
4255         }
4256         if (!err)
4257                 err = percpu_counter_init(&sbi->s_dirs_counter,
4258                                           ext4_count_dirs(sb), GFP_KERNEL);
4259         if (!err)
4260                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4261                                           GFP_KERNEL);
4262         if (!err)
4263                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4264
4265         if (err) {
4266                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4267                 goto failed_mount6;
4268         }
4269
4270         if (ext4_has_feature_flex_bg(sb))
4271                 if (!ext4_fill_flex_info(sb)) {
4272                         ext4_msg(sb, KERN_ERR,
4273                                "unable to initialize "
4274                                "flex_bg meta info!");
4275                         goto failed_mount6;
4276                 }
4277
4278         err = ext4_register_li_request(sb, first_not_zeroed);
4279         if (err)
4280                 goto failed_mount6;
4281
4282         err = ext4_register_sysfs(sb);
4283         if (err)
4284                 goto failed_mount7;
4285
4286 #ifdef CONFIG_QUOTA
4287         /* Enable quota usage during mount. */
4288         if (ext4_has_feature_quota(sb) && !(sb->s_flags & MS_RDONLY)) {
4289                 err = ext4_enable_quotas(sb);
4290                 if (err)
4291                         goto failed_mount8;
4292         }
4293 #endif  /* CONFIG_QUOTA */
4294
4295         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4296         ext4_orphan_cleanup(sb, es);
4297         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4298         if (needs_recovery) {
4299                 ext4_msg(sb, KERN_INFO, "recovery complete");
4300                 ext4_mark_recovery_complete(sb, es);
4301         }
4302         if (EXT4_SB(sb)->s_journal) {
4303                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4304                         descr = " journalled data mode";
4305                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4306                         descr = " ordered data mode";
4307                 else
4308                         descr = " writeback data mode";
4309         } else
4310                 descr = "out journal";
4311
4312         if (test_opt(sb, DISCARD)) {
4313                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4314                 if (!blk_queue_discard(q))
4315                         ext4_msg(sb, KERN_WARNING,
4316                                  "mounting with \"discard\" option, but "
4317                                  "the device does not support discard");
4318         }
4319
4320         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4321                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4322                          "Opts: %.*s%s%s", descr,
4323                          (int) sizeof(sbi->s_es->s_mount_opts),
4324                          sbi->s_es->s_mount_opts,
4325                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4326
4327         if (es->s_error_count)
4328                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4329
4330         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4331         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4332         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4333         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4334
4335         kfree(orig_data);
4336         return 0;
4337
4338 cantfind_ext4:
4339         if (!silent)
4340                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4341         goto failed_mount;
4342
4343 #ifdef CONFIG_QUOTA
4344 failed_mount8:
4345         ext4_unregister_sysfs(sb);
4346 #endif
4347 failed_mount7:
4348         ext4_unregister_li_request(sb);
4349 failed_mount6:
4350         ext4_mb_release(sb);
4351         if (sbi->s_flex_groups)
4352                 kvfree(sbi->s_flex_groups);
4353         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4354         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4355         percpu_counter_destroy(&sbi->s_dirs_counter);
4356         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4357 failed_mount5:
4358         ext4_ext_release(sb);
4359         ext4_release_system_zone(sb);
4360 failed_mount4a:
4361         dput(sb->s_root);
4362         sb->s_root = NULL;
4363 failed_mount4:
4364         ext4_msg(sb, KERN_ERR, "mount failed");
4365         if (EXT4_SB(sb)->rsv_conversion_wq)
4366                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4367 failed_mount_wq:
4368         if (sbi->s_ea_inode_cache) {
4369                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4370                 sbi->s_ea_inode_cache = NULL;
4371         }
4372         if (sbi->s_ea_block_cache) {
4373                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4374                 sbi->s_ea_block_cache = NULL;
4375         }
4376         if (sbi->s_journal) {
4377                 jbd2_journal_destroy(sbi->s_journal);
4378                 sbi->s_journal = NULL;
4379         }
4380 failed_mount3a:
4381         ext4_es_unregister_shrinker(sbi);
4382 failed_mount3:
4383         del_timer_sync(&sbi->s_err_report);
4384         if (sbi->s_mmp_tsk)
4385                 kthread_stop(sbi->s_mmp_tsk);
4386 failed_mount2:
4387         for (i = 0; i < db_count; i++)
4388                 brelse(sbi->s_group_desc[i]);
4389         kvfree(sbi->s_group_desc);
4390 failed_mount:
4391         if (sbi->s_chksum_driver)
4392                 crypto_free_shash(sbi->s_chksum_driver);
4393 #ifdef CONFIG_QUOTA
4394         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4395                 kfree(sbi->s_qf_names[i]);
4396 #endif
4397         ext4_blkdev_remove(sbi);
4398         brelse(bh);
4399 out_fail:
4400         sb->s_fs_info = NULL;
4401         kfree(sbi->s_blockgroup_lock);
4402 out_free_base:
4403         kfree(sbi);
4404         kfree(orig_data);
4405         fs_put_dax(dax_dev);
4406         return err ? err : ret;
4407 }
4408
4409 /*
4410  * Setup any per-fs journal parameters now.  We'll do this both on
4411  * initial mount, once the journal has been initialised but before we've
4412  * done any recovery; and again on any subsequent remount.
4413  */
4414 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4415 {
4416         struct ext4_sb_info *sbi = EXT4_SB(sb);
4417
4418         journal->j_commit_interval = sbi->s_commit_interval;
4419         journal->j_min_batch_time = sbi->s_min_batch_time;
4420         journal->j_max_batch_time = sbi->s_max_batch_time;
4421
4422         write_lock(&journal->j_state_lock);
4423         if (test_opt(sb, BARRIER))
4424                 journal->j_flags |= JBD2_BARRIER;
4425         else
4426                 journal->j_flags &= ~JBD2_BARRIER;
4427         if (test_opt(sb, DATA_ERR_ABORT))
4428                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4429         else
4430                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4431         write_unlock(&journal->j_state_lock);
4432 }
4433
4434 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4435                                              unsigned int journal_inum)
4436 {
4437         struct inode *journal_inode;
4438
4439         /*
4440          * Test for the existence of a valid inode on disk.  Bad things
4441          * happen if we iget() an unused inode, as the subsequent iput()
4442          * will try to delete it.
4443          */
4444         journal_inode = ext4_iget(sb, journal_inum);
4445         if (IS_ERR(journal_inode)) {
4446                 ext4_msg(sb, KERN_ERR, "no journal found");
4447                 return NULL;
4448         }
4449         if (!journal_inode->i_nlink) {
4450                 make_bad_inode(journal_inode);
4451                 iput(journal_inode);
4452                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4453                 return NULL;
4454         }
4455
4456         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4457                   journal_inode, journal_inode->i_size);
4458         if (!S_ISREG(journal_inode->i_mode)) {
4459                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4460                 iput(journal_inode);
4461                 return NULL;
4462         }
4463         return journal_inode;
4464 }
4465
4466 static journal_t *ext4_get_journal(struct super_block *sb,
4467                                    unsigned int journal_inum)
4468 {
4469         struct inode *journal_inode;
4470         journal_t *journal;
4471
4472         BUG_ON(!ext4_has_feature_journal(sb));
4473
4474         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4475         if (!journal_inode)
4476                 return NULL;
4477
4478         journal = jbd2_journal_init_inode(journal_inode);
4479         if (!journal) {
4480                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4481                 iput(journal_inode);
4482                 return NULL;
4483         }
4484         journal->j_private = sb;
4485         ext4_init_journal_params(sb, journal);
4486         return journal;
4487 }
4488
4489 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4490                                        dev_t j_dev)
4491 {
4492         struct buffer_head *bh;
4493         journal_t *journal;
4494         ext4_fsblk_t start;
4495         ext4_fsblk_t len;
4496         int hblock, blocksize;
4497         ext4_fsblk_t sb_block;
4498         unsigned long offset;
4499         struct ext4_super_block *es;
4500         struct block_device *bdev;
4501
4502         BUG_ON(!ext4_has_feature_journal(sb));
4503
4504         bdev = ext4_blkdev_get(j_dev, sb);
4505         if (bdev == NULL)
4506                 return NULL;
4507
4508         blocksize = sb->s_blocksize;
4509         hblock = bdev_logical_block_size(bdev);
4510         if (blocksize < hblock) {
4511                 ext4_msg(sb, KERN_ERR,
4512                         "blocksize too small for journal device");
4513                 goto out_bdev;
4514         }
4515
4516         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4517         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4518         set_blocksize(bdev, blocksize);
4519         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4520                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4521                        "external journal");
4522                 goto out_bdev;
4523         }
4524
4525         es = (struct ext4_super_block *) (bh->b_data + offset);
4526         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4527             !(le32_to_cpu(es->s_feature_incompat) &
4528               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4529                 ext4_msg(sb, KERN_ERR, "external journal has "
4530                                         "bad superblock");
4531                 brelse(bh);
4532                 goto out_bdev;
4533         }
4534
4535         if ((le32_to_cpu(es->s_feature_ro_compat) &
4536              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4537             es->s_checksum != ext4_superblock_csum(sb, es)) {
4538                 ext4_msg(sb, KERN_ERR, "external journal has "
4539                                        "corrupt superblock");
4540                 brelse(bh);
4541                 goto out_bdev;
4542         }
4543
4544         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4545                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4546                 brelse(bh);
4547                 goto out_bdev;
4548         }
4549
4550         len = ext4_blocks_count(es);
4551         start = sb_block + 1;
4552         brelse(bh);     /* we're done with the superblock */
4553
4554         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4555                                         start, len, blocksize);
4556         if (!journal) {
4557                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4558                 goto out_bdev;
4559         }
4560         journal->j_private = sb;
4561         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4562         wait_on_buffer(journal->j_sb_buffer);
4563         if (!buffer_uptodate(journal->j_sb_buffer)) {
4564                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4565                 goto out_journal;
4566         }
4567         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4568                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4569                                         "user (unsupported) - %d",
4570                         be32_to_cpu(journal->j_superblock->s_nr_users));
4571                 goto out_journal;
4572         }
4573         EXT4_SB(sb)->journal_bdev = bdev;
4574         ext4_init_journal_params(sb, journal);
4575         return journal;
4576
4577 out_journal:
4578         jbd2_journal_destroy(journal);
4579 out_bdev:
4580         ext4_blkdev_put(bdev);
4581         return NULL;
4582 }
4583
4584 static int ext4_load_journal(struct super_block *sb,
4585                              struct ext4_super_block *es,
4586                              unsigned long journal_devnum)
4587 {
4588         journal_t *journal;
4589         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4590         dev_t journal_dev;
4591         int err = 0;
4592         int really_read_only;
4593
4594         BUG_ON(!ext4_has_feature_journal(sb));
4595
4596         if (journal_devnum &&
4597             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4598                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4599                         "numbers have changed");
4600                 journal_dev = new_decode_dev(journal_devnum);
4601         } else
4602                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4603
4604         really_read_only = bdev_read_only(sb->s_bdev);
4605
4606         /*
4607          * Are we loading a blank journal or performing recovery after a
4608          * crash?  For recovery, we need to check in advance whether we
4609          * can get read-write access to the device.
4610          */
4611         if (ext4_has_feature_journal_needs_recovery(sb)) {
4612                 if (sb->s_flags & MS_RDONLY) {
4613                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4614                                         "required on readonly filesystem");
4615                         if (really_read_only) {
4616                                 ext4_msg(sb, KERN_ERR, "write access "
4617                                         "unavailable, cannot proceed");
4618                                 return -EROFS;
4619                         }
4620                         ext4_msg(sb, KERN_INFO, "write access will "
4621                                "be enabled during recovery");
4622                 }
4623         }
4624
4625         if (journal_inum && journal_dev) {
4626                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4627                        "and inode journals!");
4628                 return -EINVAL;
4629         }
4630
4631         if (journal_inum) {
4632                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4633                         return -EINVAL;
4634         } else {
4635                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4636                         return -EINVAL;
4637         }
4638
4639         if (!(journal->j_flags & JBD2_BARRIER))
4640                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4641
4642         if (!ext4_has_feature_journal_needs_recovery(sb))
4643                 err = jbd2_journal_wipe(journal, !really_read_only);
4644         if (!err) {
4645                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4646                 if (save)
4647                         memcpy(save, ((char *) es) +
4648                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4649                 err = jbd2_journal_load(journal);
4650                 if (save)
4651                         memcpy(((char *) es) + EXT4_S_ERR_START,
4652                                save, EXT4_S_ERR_LEN);
4653                 kfree(save);
4654         }
4655
4656         if (err) {
4657                 ext4_msg(sb, KERN_ERR, "error loading journal");
4658                 jbd2_journal_destroy(journal);
4659                 return err;
4660         }
4661
4662         EXT4_SB(sb)->s_journal = journal;
4663         ext4_clear_journal_err(sb, es);
4664
4665         if (!really_read_only && journal_devnum &&
4666             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4667                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4668
4669                 /* Make sure we flush the recovery flag to disk. */
4670                 ext4_commit_super(sb, 1);
4671         }
4672
4673         return 0;
4674 }
4675
4676 static int ext4_commit_super(struct super_block *sb, int sync)
4677 {
4678         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4679         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4680         int error = 0;
4681
4682         if (!sbh || block_device_ejected(sb))
4683                 return error;
4684         /*
4685          * If the file system is mounted read-only, don't update the
4686          * superblock write time.  This avoids updating the superblock
4687          * write time when we are mounting the root file system
4688          * read/only but we need to replay the journal; at that point,
4689          * for people who are east of GMT and who make their clock
4690          * tick in localtime for Windows bug-for-bug compatibility,
4691          * the clock is set in the future, and this will cause e2fsck
4692          * to complain and force a full file system check.
4693          */
4694         if (!(sb->s_flags & MS_RDONLY))
4695                 es->s_wtime = cpu_to_le32(get_seconds());
4696         if (sb->s_bdev->bd_part)
4697                 es->s_kbytes_written =
4698                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4699                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4700                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4701         else
4702                 es->s_kbytes_written =
4703                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4704         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4705                 ext4_free_blocks_count_set(es,
4706                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4707                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4708         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4709                 es->s_free_inodes_count =
4710                         cpu_to_le32(percpu_counter_sum_positive(
4711                                 &EXT4_SB(sb)->s_freeinodes_counter));
4712         BUFFER_TRACE(sbh, "marking dirty");
4713         ext4_superblock_csum_set(sb);
4714         if (sync)
4715                 lock_buffer(sbh);
4716         if (buffer_write_io_error(sbh)) {
4717                 /*
4718                  * Oh, dear.  A previous attempt to write the
4719                  * superblock failed.  This could happen because the
4720                  * USB device was yanked out.  Or it could happen to
4721                  * be a transient write error and maybe the block will
4722                  * be remapped.  Nothing we can do but to retry the
4723                  * write and hope for the best.
4724                  */
4725                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4726                        "superblock detected");
4727                 clear_buffer_write_io_error(sbh);
4728                 set_buffer_uptodate(sbh);
4729         }
4730         mark_buffer_dirty(sbh);
4731         if (sync) {
4732                 unlock_buffer(sbh);
4733                 error = __sync_dirty_buffer(sbh,
4734                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
4735                 if (error)
4736                         return error;
4737
4738                 error = buffer_write_io_error(sbh);
4739                 if (error) {
4740                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4741                                "superblock");
4742                         clear_buffer_write_io_error(sbh);
4743                         set_buffer_uptodate(sbh);
4744                 }
4745         }
4746         return error;
4747 }
4748
4749 /*
4750  * Have we just finished recovery?  If so, and if we are mounting (or
4751  * remounting) the filesystem readonly, then we will end up with a
4752  * consistent fs on disk.  Record that fact.
4753  */
4754 static void ext4_mark_recovery_complete(struct super_block *sb,
4755                                         struct ext4_super_block *es)
4756 {
4757         journal_t *journal = EXT4_SB(sb)->s_journal;
4758
4759         if (!ext4_has_feature_journal(sb)) {
4760                 BUG_ON(journal != NULL);
4761                 return;
4762         }
4763         jbd2_journal_lock_updates(journal);
4764         if (jbd2_journal_flush(journal) < 0)
4765                 goto out;
4766
4767         if (ext4_has_feature_journal_needs_recovery(sb) &&
4768             sb->s_flags & MS_RDONLY) {
4769                 ext4_clear_feature_journal_needs_recovery(sb);
4770                 ext4_commit_super(sb, 1);
4771         }
4772
4773 out:
4774         jbd2_journal_unlock_updates(journal);
4775 }
4776
4777 /*
4778  * If we are mounting (or read-write remounting) a filesystem whose journal
4779  * has recorded an error from a previous lifetime, move that error to the
4780  * main filesystem now.
4781  */
4782 static void ext4_clear_journal_err(struct super_block *sb,
4783                                    struct ext4_super_block *es)
4784 {
4785         journal_t *journal;
4786         int j_errno;
4787         const char *errstr;
4788
4789         BUG_ON(!ext4_has_feature_journal(sb));
4790
4791         journal = EXT4_SB(sb)->s_journal;
4792
4793         /*
4794          * Now check for any error status which may have been recorded in the
4795          * journal by a prior ext4_error() or ext4_abort()
4796          */
4797
4798         j_errno = jbd2_journal_errno(journal);
4799         if (j_errno) {
4800                 char nbuf[16];
4801
4802                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4803                 ext4_warning(sb, "Filesystem error recorded "
4804                              "from previous mount: %s", errstr);
4805                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4806
4807                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4808                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4809                 ext4_commit_super(sb, 1);
4810
4811                 jbd2_journal_clear_err(journal);
4812                 jbd2_journal_update_sb_errno(journal);
4813         }
4814 }
4815
4816 /*
4817  * Force the running and committing transactions to commit,
4818  * and wait on the commit.
4819  */
4820 int ext4_force_commit(struct super_block *sb)
4821 {
4822         journal_t *journal;
4823
4824         if (sb->s_flags & MS_RDONLY)
4825                 return 0;
4826
4827         journal = EXT4_SB(sb)->s_journal;
4828         return ext4_journal_force_commit(journal);
4829 }
4830
4831 static int ext4_sync_fs(struct super_block *sb, int wait)
4832 {
4833         int ret = 0;
4834         tid_t target;
4835         bool needs_barrier = false;
4836         struct ext4_sb_info *sbi = EXT4_SB(sb);
4837
4838         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
4839                 return 0;
4840
4841         trace_ext4_sync_fs(sb, wait);
4842         flush_workqueue(sbi->rsv_conversion_wq);
4843         /*
4844          * Writeback quota in non-journalled quota case - journalled quota has
4845          * no dirty dquots
4846          */
4847         dquot_writeback_dquots(sb, -1);
4848         /*
4849          * Data writeback is possible w/o journal transaction, so barrier must
4850          * being sent at the end of the function. But we can skip it if
4851          * transaction_commit will do it for us.
4852          */
4853         if (sbi->s_journal) {
4854                 target = jbd2_get_latest_transaction(sbi->s_journal);
4855                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4856                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4857                         needs_barrier = true;
4858
4859                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4860                         if (wait)
4861                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4862                                                            target);
4863                 }
4864         } else if (wait && test_opt(sb, BARRIER))
4865                 needs_barrier = true;
4866         if (needs_barrier) {
4867                 int err;
4868                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4869                 if (!ret)
4870                         ret = err;
4871         }
4872
4873         return ret;
4874 }
4875
4876 /*
4877  * LVM calls this function before a (read-only) snapshot is created.  This
4878  * gives us a chance to flush the journal completely and mark the fs clean.
4879  *
4880  * Note that only this function cannot bring a filesystem to be in a clean
4881  * state independently. It relies on upper layer to stop all data & metadata
4882  * modifications.
4883  */
4884 static int ext4_freeze(struct super_block *sb)
4885 {
4886         int error = 0;
4887         journal_t *journal;
4888
4889         if (sb->s_flags & MS_RDONLY)
4890                 return 0;
4891
4892         journal = EXT4_SB(sb)->s_journal;
4893
4894         if (journal) {
4895                 /* Now we set up the journal barrier. */
4896                 jbd2_journal_lock_updates(journal);
4897
4898                 /*
4899                  * Don't clear the needs_recovery flag if we failed to
4900                  * flush the journal.
4901                  */
4902                 error = jbd2_journal_flush(journal);
4903                 if (error < 0)
4904                         goto out;
4905
4906                 /* Journal blocked and flushed, clear needs_recovery flag. */
4907                 ext4_clear_feature_journal_needs_recovery(sb);
4908         }
4909
4910         error = ext4_commit_super(sb, 1);
4911 out:
4912         if (journal)
4913                 /* we rely on upper layer to stop further updates */
4914                 jbd2_journal_unlock_updates(journal);
4915         return error;
4916 }
4917
4918 /*
4919  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4920  * flag here, even though the filesystem is not technically dirty yet.
4921  */
4922 static int ext4_unfreeze(struct super_block *sb)
4923 {
4924         if ((sb->s_flags & MS_RDONLY) || ext4_forced_shutdown(EXT4_SB(sb)))
4925                 return 0;
4926
4927         if (EXT4_SB(sb)->s_journal) {
4928                 /* Reset the needs_recovery flag before the fs is unlocked. */
4929                 ext4_set_feature_journal_needs_recovery(sb);
4930         }
4931
4932         ext4_commit_super(sb, 1);
4933         return 0;
4934 }
4935
4936 /*
4937  * Structure to save mount options for ext4_remount's benefit
4938  */
4939 struct ext4_mount_options {
4940         unsigned long s_mount_opt;
4941         unsigned long s_mount_opt2;
4942         kuid_t s_resuid;
4943         kgid_t s_resgid;
4944         unsigned long s_commit_interval;
4945         u32 s_min_batch_time, s_max_batch_time;
4946 #ifdef CONFIG_QUOTA
4947         int s_jquota_fmt;
4948         char *s_qf_names[EXT4_MAXQUOTAS];
4949 #endif
4950 };
4951
4952 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4953 {
4954         struct ext4_super_block *es;
4955         struct ext4_sb_info *sbi = EXT4_SB(sb);
4956         unsigned long old_sb_flags;
4957         struct ext4_mount_options old_opts;
4958         int enable_quota = 0;
4959         ext4_group_t g;
4960         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4961         int err = 0;
4962 #ifdef CONFIG_QUOTA
4963         int i, j;
4964 #endif
4965         char *orig_data = kstrdup(data, GFP_KERNEL);
4966
4967         /* Store the original options */
4968         old_sb_flags = sb->s_flags;
4969         old_opts.s_mount_opt = sbi->s_mount_opt;
4970         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4971         old_opts.s_resuid = sbi->s_resuid;
4972         old_opts.s_resgid = sbi->s_resgid;
4973         old_opts.s_commit_interval = sbi->s_commit_interval;
4974         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4975         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4976 #ifdef CONFIG_QUOTA
4977         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4978         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4979                 if (sbi->s_qf_names[i]) {
4980                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4981                                                          GFP_KERNEL);
4982                         if (!old_opts.s_qf_names[i]) {
4983                                 for (j = 0; j < i; j++)
4984                                         kfree(old_opts.s_qf_names[j]);
4985                                 kfree(orig_data);
4986                                 return -ENOMEM;
4987                         }
4988                 } else
4989                         old_opts.s_qf_names[i] = NULL;
4990 #endif
4991         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
4992                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
4993
4994         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
4995                 err = -EINVAL;
4996                 goto restore_opts;
4997         }
4998
4999         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5000             test_opt(sb, JOURNAL_CHECKSUM)) {
5001                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5002                          "during remount not supported; ignoring");
5003                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5004         }
5005
5006         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5007                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5008                         ext4_msg(sb, KERN_ERR, "can't mount with "
5009                                  "both data=journal and delalloc");
5010                         err = -EINVAL;
5011                         goto restore_opts;
5012                 }
5013                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5014                         ext4_msg(sb, KERN_ERR, "can't mount with "
5015                                  "both data=journal and dioread_nolock");
5016                         err = -EINVAL;
5017                         goto restore_opts;
5018                 }
5019                 if (test_opt(sb, DAX)) {
5020                         ext4_msg(sb, KERN_ERR, "can't mount with "
5021                                  "both data=journal and dax");
5022                         err = -EINVAL;
5023                         goto restore_opts;
5024                 }
5025         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5026                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5027                         ext4_msg(sb, KERN_ERR, "can't mount with "
5028                                 "journal_async_commit in data=ordered mode");
5029                         err = -EINVAL;
5030                         goto restore_opts;
5031                 }
5032         }
5033
5034         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5035                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5036                 err = -EINVAL;
5037                 goto restore_opts;
5038         }
5039
5040         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5041                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5042                         "dax flag with busy inodes while remounting");
5043                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5044         }
5045
5046         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5047                 ext4_abort(sb, "Abort forced by user");
5048
5049         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
5050                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
5051
5052         es = sbi->s_es;
5053
5054         if (sbi->s_journal) {
5055                 ext4_init_journal_params(sb, sbi->s_journal);
5056                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5057         }
5058
5059         if (*flags & MS_LAZYTIME)
5060                 sb->s_flags |= MS_LAZYTIME;
5061
5062         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
5063                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5064                         err = -EROFS;
5065                         goto restore_opts;
5066                 }
5067
5068                 if (*flags & MS_RDONLY) {
5069                         err = sync_filesystem(sb);
5070                         if (err < 0)
5071                                 goto restore_opts;
5072                         err = dquot_suspend(sb, -1);
5073                         if (err < 0)
5074                                 goto restore_opts;
5075
5076                         /*
5077                          * First of all, the unconditional stuff we have to do
5078                          * to disable replay of the journal when we next remount
5079                          */
5080                         sb->s_flags |= MS_RDONLY;
5081
5082                         /*
5083                          * OK, test if we are remounting a valid rw partition
5084                          * readonly, and if so set the rdonly flag and then
5085                          * mark the partition as valid again.
5086                          */
5087                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5088                             (sbi->s_mount_state & EXT4_VALID_FS))
5089                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5090
5091                         if (sbi->s_journal)
5092                                 ext4_mark_recovery_complete(sb, es);
5093                 } else {
5094                         /* Make sure we can mount this feature set readwrite */
5095                         if (ext4_has_feature_readonly(sb) ||
5096                             !ext4_feature_set_ok(sb, 0)) {
5097                                 err = -EROFS;
5098                                 goto restore_opts;
5099                         }
5100                         /*
5101                          * Make sure the group descriptor checksums
5102                          * are sane.  If they aren't, refuse to remount r/w.
5103                          */
5104                         for (g = 0; g < sbi->s_groups_count; g++) {
5105                                 struct ext4_group_desc *gdp =
5106                                         ext4_get_group_desc(sb, g, NULL);
5107
5108                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5109                                         ext4_msg(sb, KERN_ERR,
5110                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5111                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5112                                                le16_to_cpu(gdp->bg_checksum));
5113                                         err = -EFSBADCRC;
5114                                         goto restore_opts;
5115                                 }
5116                         }
5117
5118                         /*
5119                          * If we have an unprocessed orphan list hanging
5120                          * around from a previously readonly bdev mount,
5121                          * require a full umount/remount for now.
5122                          */
5123                         if (es->s_last_orphan) {
5124                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5125                                        "remount RDWR because of unprocessed "
5126                                        "orphan inode list.  Please "
5127                                        "umount/remount instead");
5128                                 err = -EINVAL;
5129                                 goto restore_opts;
5130                         }
5131
5132                         /*
5133                          * Mounting a RDONLY partition read-write, so reread
5134                          * and store the current valid flag.  (It may have
5135                          * been changed by e2fsck since we originally mounted
5136                          * the partition.)
5137                          */
5138                         if (sbi->s_journal)
5139                                 ext4_clear_journal_err(sb, es);
5140                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5141                         if (!ext4_setup_super(sb, es, 0))
5142                                 sb->s_flags &= ~MS_RDONLY;
5143                         if (ext4_has_feature_mmp(sb))
5144                                 if (ext4_multi_mount_protect(sb,
5145                                                 le64_to_cpu(es->s_mmp_block))) {
5146                                         err = -EROFS;
5147                                         goto restore_opts;
5148                                 }
5149                         enable_quota = 1;
5150                 }
5151         }
5152
5153         /*
5154          * Reinitialize lazy itable initialization thread based on
5155          * current settings
5156          */
5157         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
5158                 ext4_unregister_li_request(sb);
5159         else {
5160                 ext4_group_t first_not_zeroed;
5161                 first_not_zeroed = ext4_has_uninit_itable(sb);
5162                 ext4_register_li_request(sb, first_not_zeroed);
5163         }
5164
5165         ext4_setup_system_zone(sb);
5166         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
5167                 ext4_commit_super(sb, 1);
5168
5169 #ifdef CONFIG_QUOTA
5170         /* Release old quota file names */
5171         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5172                 kfree(old_opts.s_qf_names[i]);
5173         if (enable_quota) {
5174                 if (sb_any_quota_suspended(sb))
5175                         dquot_resume(sb, -1);
5176                 else if (ext4_has_feature_quota(sb)) {
5177                         err = ext4_enable_quotas(sb);
5178                         if (err)
5179                                 goto restore_opts;
5180                 }
5181         }
5182 #endif
5183
5184         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
5185         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5186         kfree(orig_data);
5187         return 0;
5188
5189 restore_opts:
5190         sb->s_flags = old_sb_flags;
5191         sbi->s_mount_opt = old_opts.s_mount_opt;
5192         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5193         sbi->s_resuid = old_opts.s_resuid;
5194         sbi->s_resgid = old_opts.s_resgid;
5195         sbi->s_commit_interval = old_opts.s_commit_interval;
5196         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5197         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5198 #ifdef CONFIG_QUOTA
5199         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5200         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5201                 kfree(sbi->s_qf_names[i]);
5202                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5203         }
5204 #endif
5205         kfree(orig_data);
5206         return err;
5207 }
5208
5209 #ifdef CONFIG_QUOTA
5210 static int ext4_statfs_project(struct super_block *sb,
5211                                kprojid_t projid, struct kstatfs *buf)
5212 {
5213         struct kqid qid;
5214         struct dquot *dquot;
5215         u64 limit;
5216         u64 curblock;
5217
5218         qid = make_kqid_projid(projid);
5219         dquot = dqget(sb, qid);
5220         if (IS_ERR(dquot))
5221                 return PTR_ERR(dquot);
5222         spin_lock(&dquot->dq_dqb_lock);
5223
5224         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5225                  dquot->dq_dqb.dqb_bsoftlimit :
5226                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5227         if (limit && buf->f_blocks > limit) {
5228                 curblock = dquot->dq_dqb.dqb_curspace >> sb->s_blocksize_bits;
5229                 buf->f_blocks = limit;
5230                 buf->f_bfree = buf->f_bavail =
5231                         (buf->f_blocks > curblock) ?
5232                          (buf->f_blocks - curblock) : 0;
5233         }
5234
5235         limit = dquot->dq_dqb.dqb_isoftlimit ?
5236                 dquot->dq_dqb.dqb_isoftlimit :
5237                 dquot->dq_dqb.dqb_ihardlimit;
5238         if (limit && buf->f_files > limit) {
5239                 buf->f_files = limit;
5240                 buf->f_ffree =
5241                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5242                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5243         }
5244
5245         spin_unlock(&dquot->dq_dqb_lock);
5246         dqput(dquot);
5247         return 0;
5248 }
5249 #endif
5250
5251 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5252 {
5253         struct super_block *sb = dentry->d_sb;
5254         struct ext4_sb_info *sbi = EXT4_SB(sb);
5255         struct ext4_super_block *es = sbi->s_es;
5256         ext4_fsblk_t overhead = 0, resv_blocks;
5257         u64 fsid;
5258         s64 bfree;
5259         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5260
5261         if (!test_opt(sb, MINIX_DF))
5262                 overhead = sbi->s_overhead;
5263
5264         buf->f_type = EXT4_SUPER_MAGIC;
5265         buf->f_bsize = sb->s_blocksize;
5266         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5267         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5268                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5269         /* prevent underflow in case that few free space is available */
5270         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5271         buf->f_bavail = buf->f_bfree -
5272                         (ext4_r_blocks_count(es) + resv_blocks);
5273         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5274                 buf->f_bavail = 0;
5275         buf->f_files = le32_to_cpu(es->s_inodes_count);
5276         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5277         buf->f_namelen = EXT4_NAME_LEN;
5278         fsid = le64_to_cpup((void *)es->s_uuid) ^
5279                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5280         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5281         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5282
5283 #ifdef CONFIG_QUOTA
5284         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5285             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5286                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5287 #endif
5288         return 0;
5289 }
5290
5291
5292 #ifdef CONFIG_QUOTA
5293
5294 /*
5295  * Helper functions so that transaction is started before we acquire dqio_sem
5296  * to keep correct lock ordering of transaction > dqio_sem
5297  */
5298 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5299 {
5300         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5301 }
5302
5303 static int ext4_write_dquot(struct dquot *dquot)
5304 {
5305         int ret, err;
5306         handle_t *handle;
5307         struct inode *inode;
5308
5309         inode = dquot_to_inode(dquot);
5310         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5311                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5312         if (IS_ERR(handle))
5313                 return PTR_ERR(handle);
5314         ret = dquot_commit(dquot);
5315         err = ext4_journal_stop(handle);
5316         if (!ret)
5317                 ret = err;
5318         return ret;
5319 }
5320
5321 static int ext4_acquire_dquot(struct dquot *dquot)
5322 {
5323         int ret, err;
5324         handle_t *handle;
5325
5326         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5327                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5328         if (IS_ERR(handle))
5329                 return PTR_ERR(handle);
5330         ret = dquot_acquire(dquot);
5331         err = ext4_journal_stop(handle);
5332         if (!ret)
5333                 ret = err;
5334         return ret;
5335 }
5336
5337 static int ext4_release_dquot(struct dquot *dquot)
5338 {
5339         int ret, err;
5340         handle_t *handle;
5341
5342         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5343                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5344         if (IS_ERR(handle)) {
5345                 /* Release dquot anyway to avoid endless cycle in dqput() */
5346                 dquot_release(dquot);
5347                 return PTR_ERR(handle);
5348         }
5349         ret = dquot_release(dquot);
5350         err = ext4_journal_stop(handle);
5351         if (!ret)
5352                 ret = err;
5353         return ret;
5354 }
5355
5356 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5357 {
5358         struct super_block *sb = dquot->dq_sb;
5359         struct ext4_sb_info *sbi = EXT4_SB(sb);
5360
5361         /* Are we journaling quotas? */
5362         if (ext4_has_feature_quota(sb) ||
5363             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5364                 dquot_mark_dquot_dirty(dquot);
5365                 return ext4_write_dquot(dquot);
5366         } else {
5367                 return dquot_mark_dquot_dirty(dquot);
5368         }
5369 }
5370
5371 static int ext4_write_info(struct super_block *sb, int type)
5372 {
5373         int ret, err;
5374         handle_t *handle;
5375
5376         /* Data block + inode block */
5377         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5378         if (IS_ERR(handle))
5379                 return PTR_ERR(handle);
5380         ret = dquot_commit_info(sb, type);
5381         err = ext4_journal_stop(handle);
5382         if (!ret)
5383                 ret = err;
5384         return ret;
5385 }
5386
5387 /*
5388  * Turn on quotas during mount time - we need to find
5389  * the quota file and such...
5390  */
5391 static int ext4_quota_on_mount(struct super_block *sb, int type)
5392 {
5393         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5394                                         EXT4_SB(sb)->s_jquota_fmt, type);
5395 }
5396
5397 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5398 {
5399         struct ext4_inode_info *ei = EXT4_I(inode);
5400
5401         /* The first argument of lockdep_set_subclass has to be
5402          * *exactly* the same as the argument to init_rwsem() --- in
5403          * this case, in init_once() --- or lockdep gets unhappy
5404          * because the name of the lock is set using the
5405          * stringification of the argument to init_rwsem().
5406          */
5407         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5408         lockdep_set_subclass(&ei->i_data_sem, subclass);
5409 }
5410
5411 /*
5412  * Standard function to be called on quota_on
5413  */
5414 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5415                          const struct path *path)
5416 {
5417         int err;
5418
5419         if (!test_opt(sb, QUOTA))
5420                 return -EINVAL;
5421
5422         /* Quotafile not on the same filesystem? */
5423         if (path->dentry->d_sb != sb)
5424                 return -EXDEV;
5425         /* Journaling quota? */
5426         if (EXT4_SB(sb)->s_qf_names[type]) {
5427                 /* Quotafile not in fs root? */
5428                 if (path->dentry->d_parent != sb->s_root)
5429                         ext4_msg(sb, KERN_WARNING,
5430                                 "Quota file not on filesystem root. "
5431                                 "Journaled quota will not work");
5432                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5433         } else {
5434                 /*
5435                  * Clear the flag just in case mount options changed since
5436                  * last time.
5437                  */
5438                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5439         }
5440
5441         /*
5442          * When we journal data on quota file, we have to flush journal to see
5443          * all updates to the file when we bypass pagecache...
5444          */
5445         if (EXT4_SB(sb)->s_journal &&
5446             ext4_should_journal_data(d_inode(path->dentry))) {
5447                 /*
5448                  * We don't need to lock updates but journal_flush() could
5449                  * otherwise be livelocked...
5450                  */
5451                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5452                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5453                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5454                 if (err)
5455                         return err;
5456         }
5457
5458         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5459         err = dquot_quota_on(sb, type, format_id, path);
5460         if (err) {
5461                 lockdep_set_quota_inode(path->dentry->d_inode,
5462                                              I_DATA_SEM_NORMAL);
5463         } else {
5464                 struct inode *inode = d_inode(path->dentry);
5465                 handle_t *handle;
5466
5467                 /*
5468                  * Set inode flags to prevent userspace from messing with quota
5469                  * files. If this fails, we return success anyway since quotas
5470                  * are already enabled and this is not a hard failure.
5471                  */
5472                 inode_lock(inode);
5473                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5474                 if (IS_ERR(handle))
5475                         goto unlock_inode;
5476                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5477                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5478                                 S_NOATIME | S_IMMUTABLE);
5479                 ext4_mark_inode_dirty(handle, inode);
5480                 ext4_journal_stop(handle);
5481         unlock_inode:
5482                 inode_unlock(inode);
5483         }
5484         return err;
5485 }
5486
5487 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5488                              unsigned int flags)
5489 {
5490         int err;
5491         struct inode *qf_inode;
5492         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5493                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5494                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5495                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5496         };
5497
5498         BUG_ON(!ext4_has_feature_quota(sb));
5499
5500         if (!qf_inums[type])
5501                 return -EPERM;
5502
5503         qf_inode = ext4_iget(sb, qf_inums[type]);
5504         if (IS_ERR(qf_inode)) {
5505                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5506                 return PTR_ERR(qf_inode);
5507         }
5508
5509         /* Don't account quota for quota files to avoid recursion */
5510         qf_inode->i_flags |= S_NOQUOTA;
5511         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5512         err = dquot_enable(qf_inode, type, format_id, flags);
5513         iput(qf_inode);
5514         if (err)
5515                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5516
5517         return err;
5518 }
5519
5520 /* Enable usage tracking for all quota types. */
5521 static int ext4_enable_quotas(struct super_block *sb)
5522 {
5523         int type, err = 0;
5524         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5525                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5526                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5527                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5528         };
5529         bool quota_mopt[EXT4_MAXQUOTAS] = {
5530                 test_opt(sb, USRQUOTA),
5531                 test_opt(sb, GRPQUOTA),
5532                 test_opt(sb, PRJQUOTA),
5533         };
5534
5535         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5536         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5537                 if (qf_inums[type]) {
5538                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5539                                 DQUOT_USAGE_ENABLED |
5540                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5541                         if (err) {
5542                                 for (type--; type >= 0; type--)
5543                                         dquot_quota_off(sb, type);
5544
5545                                 ext4_warning(sb,
5546                                         "Failed to enable quota tracking "
5547                                         "(type=%d, err=%d). Please run "
5548                                         "e2fsck to fix.", type, err);
5549                                 return err;
5550                         }
5551                 }
5552         }
5553         return 0;
5554 }
5555
5556 static int ext4_quota_off(struct super_block *sb, int type)
5557 {
5558         struct inode *inode = sb_dqopt(sb)->files[type];
5559         handle_t *handle;
5560         int err;
5561
5562         /* Force all delayed allocation blocks to be allocated.
5563          * Caller already holds s_umount sem */
5564         if (test_opt(sb, DELALLOC))
5565                 sync_filesystem(sb);
5566
5567         if (!inode || !igrab(inode))
5568                 goto out;
5569
5570         err = dquot_quota_off(sb, type);
5571         if (err || ext4_has_feature_quota(sb))
5572                 goto out_put;
5573
5574         inode_lock(inode);
5575         /*
5576          * Update modification times of quota files when userspace can
5577          * start looking at them. If we fail, we return success anyway since
5578          * this is not a hard failure and quotas are already disabled.
5579          */
5580         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5581         if (IS_ERR(handle))
5582                 goto out_unlock;
5583         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5584         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5585         inode->i_mtime = inode->i_ctime = current_time(inode);
5586         ext4_mark_inode_dirty(handle, inode);
5587         ext4_journal_stop(handle);
5588 out_unlock:
5589         inode_unlock(inode);
5590 out_put:
5591         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5592         iput(inode);
5593         return err;
5594 out:
5595         return dquot_quota_off(sb, type);
5596 }
5597
5598 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5599  * acquiring the locks... As quota files are never truncated and quota code
5600  * itself serializes the operations (and no one else should touch the files)
5601  * we don't have to be afraid of races */
5602 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5603                                size_t len, loff_t off)
5604 {
5605         struct inode *inode = sb_dqopt(sb)->files[type];
5606         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5607         int offset = off & (sb->s_blocksize - 1);
5608         int tocopy;
5609         size_t toread;
5610         struct buffer_head *bh;
5611         loff_t i_size = i_size_read(inode);
5612
5613         if (off > i_size)
5614                 return 0;
5615         if (off+len > i_size)
5616                 len = i_size-off;
5617         toread = len;
5618         while (toread > 0) {
5619                 tocopy = sb->s_blocksize - offset < toread ?
5620                                 sb->s_blocksize - offset : toread;
5621                 bh = ext4_bread(NULL, inode, blk, 0);
5622                 if (IS_ERR(bh))
5623                         return PTR_ERR(bh);
5624                 if (!bh)        /* A hole? */
5625                         memset(data, 0, tocopy);
5626                 else
5627                         memcpy(data, bh->b_data+offset, tocopy);
5628                 brelse(bh);
5629                 offset = 0;
5630                 toread -= tocopy;
5631                 data += tocopy;
5632                 blk++;
5633         }
5634         return len;
5635 }
5636
5637 /* Write to quotafile (we know the transaction is already started and has
5638  * enough credits) */
5639 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5640                                 const char *data, size_t len, loff_t off)
5641 {
5642         struct inode *inode = sb_dqopt(sb)->files[type];
5643         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5644         int err, offset = off & (sb->s_blocksize - 1);
5645         int retries = 0;
5646         struct buffer_head *bh;
5647         handle_t *handle = journal_current_handle();
5648
5649         if (EXT4_SB(sb)->s_journal && !handle) {
5650                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5651                         " cancelled because transaction is not started",
5652                         (unsigned long long)off, (unsigned long long)len);
5653                 return -EIO;
5654         }
5655         /*
5656          * Since we account only one data block in transaction credits,
5657          * then it is impossible to cross a block boundary.
5658          */
5659         if (sb->s_blocksize - offset < len) {
5660                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5661                         " cancelled because not block aligned",
5662                         (unsigned long long)off, (unsigned long long)len);
5663                 return -EIO;
5664         }
5665
5666         do {
5667                 bh = ext4_bread(handle, inode, blk,
5668                                 EXT4_GET_BLOCKS_CREATE |
5669                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5670         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5671                  ext4_should_retry_alloc(inode->i_sb, &retries));
5672         if (IS_ERR(bh))
5673                 return PTR_ERR(bh);
5674         if (!bh)
5675                 goto out;
5676         BUFFER_TRACE(bh, "get write access");
5677         err = ext4_journal_get_write_access(handle, bh);
5678         if (err) {
5679                 brelse(bh);
5680                 return err;
5681         }
5682         lock_buffer(bh);
5683         memcpy(bh->b_data+offset, data, len);
5684         flush_dcache_page(bh->b_page);
5685         unlock_buffer(bh);
5686         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5687         brelse(bh);
5688 out:
5689         if (inode->i_size < off + len) {
5690                 i_size_write(inode, off + len);
5691                 EXT4_I(inode)->i_disksize = inode->i_size;
5692                 ext4_mark_inode_dirty(handle, inode);
5693         }
5694         return len;
5695 }
5696
5697 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5698 {
5699         const struct quota_format_ops   *ops;
5700
5701         if (!sb_has_quota_loaded(sb, qid->type))
5702                 return -ESRCH;
5703         ops = sb_dqopt(sb)->ops[qid->type];
5704         if (!ops || !ops->get_next_id)
5705                 return -ENOSYS;
5706         return dquot_get_next_id(sb, qid);
5707 }
5708 #endif
5709
5710 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5711                        const char *dev_name, void *data)
5712 {
5713         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5714 }
5715
5716 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5717 static inline void register_as_ext2(void)
5718 {
5719         int err = register_filesystem(&ext2_fs_type);
5720         if (err)
5721                 printk(KERN_WARNING
5722                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5723 }
5724
5725 static inline void unregister_as_ext2(void)
5726 {
5727         unregister_filesystem(&ext2_fs_type);
5728 }
5729
5730 static inline int ext2_feature_set_ok(struct super_block *sb)
5731 {
5732         if (ext4_has_unknown_ext2_incompat_features(sb))
5733                 return 0;
5734         if (sb->s_flags & MS_RDONLY)
5735                 return 1;
5736         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5737                 return 0;
5738         return 1;
5739 }
5740 #else
5741 static inline void register_as_ext2(void) { }
5742 static inline void unregister_as_ext2(void) { }
5743 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5744 #endif
5745
5746 static inline void register_as_ext3(void)
5747 {
5748         int err = register_filesystem(&ext3_fs_type);
5749         if (err)
5750                 printk(KERN_WARNING
5751                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5752 }
5753
5754 static inline void unregister_as_ext3(void)
5755 {
5756         unregister_filesystem(&ext3_fs_type);
5757 }
5758
5759 static inline int ext3_feature_set_ok(struct super_block *sb)
5760 {
5761         if (ext4_has_unknown_ext3_incompat_features(sb))
5762                 return 0;
5763         if (!ext4_has_feature_journal(sb))
5764                 return 0;
5765         if (sb->s_flags & MS_RDONLY)
5766                 return 1;
5767         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5768                 return 0;
5769         return 1;
5770 }
5771
5772 static struct file_system_type ext4_fs_type = {
5773         .owner          = THIS_MODULE,
5774         .name           = "ext4",
5775         .mount          = ext4_mount,
5776         .kill_sb        = kill_block_super,
5777         .fs_flags       = FS_REQUIRES_DEV,
5778 };
5779 MODULE_ALIAS_FS("ext4");
5780
5781 /* Shared across all ext4 file systems */
5782 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5783
5784 static int __init ext4_init_fs(void)
5785 {
5786         int i, err;
5787
5788         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5789         ext4_li_info = NULL;
5790         mutex_init(&ext4_li_mtx);
5791
5792         /* Build-time check for flags consistency */
5793         ext4_check_flag_values();
5794
5795         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
5796                 init_waitqueue_head(&ext4__ioend_wq[i]);
5797
5798         err = ext4_init_es();
5799         if (err)
5800                 return err;
5801
5802         err = ext4_init_pageio();
5803         if (err)
5804                 goto out5;
5805
5806         err = ext4_init_system_zone();
5807         if (err)
5808                 goto out4;
5809
5810         err = ext4_init_sysfs();
5811         if (err)
5812                 goto out3;
5813
5814         err = ext4_init_mballoc();
5815         if (err)
5816                 goto out2;
5817         err = init_inodecache();
5818         if (err)
5819                 goto out1;
5820         register_as_ext3();
5821         register_as_ext2();
5822         err = register_filesystem(&ext4_fs_type);
5823         if (err)
5824                 goto out;
5825
5826         return 0;
5827 out:
5828         unregister_as_ext2();
5829         unregister_as_ext3();
5830         destroy_inodecache();
5831 out1:
5832         ext4_exit_mballoc();
5833 out2:
5834         ext4_exit_sysfs();
5835 out3:
5836         ext4_exit_system_zone();
5837 out4:
5838         ext4_exit_pageio();
5839 out5:
5840         ext4_exit_es();
5841
5842         return err;
5843 }
5844
5845 static void __exit ext4_exit_fs(void)
5846 {
5847         ext4_destroy_lazyinit_thread();
5848         unregister_as_ext2();
5849         unregister_as_ext3();
5850         unregister_filesystem(&ext4_fs_type);
5851         destroy_inodecache();
5852         ext4_exit_mballoc();
5853         ext4_exit_sysfs();
5854         ext4_exit_system_zone();
5855         ext4_exit_pageio();
5856         ext4_exit_es();
5857 }
5858
5859 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5860 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5861 MODULE_LICENSE("GPL");
5862 module_init(ext4_init_fs)
5863 module_exit(ext4_exit_fs)