fs/nilfs2/inode.c

   1 /*
   2  * inode.c - NILFS inode operations.
   3  *
   4  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  * Written by Ryusuke Konishi <ryusuke@osrg.net>
  21  *
  22  */
  23
  24 #include <linux/buffer_head.h>
  25 #include <linux/gfp.h>
  26 #include <linux/mpage.h>
  27 #include <linux/writeback.h>
  28 #include <linux/uio.h>
  29 #include "nilfs.h"
  30 #include "segment.h"
  31 #include "page.h"
  32 #include "mdt.h"
  33 #include "cpfile.h"
  34 #include "ifile.h"
  35
  36
  37 /**
  38  * nilfs_get_block() - get a file block on the filesystem (callback function)
  39  * @inode - inode struct of the target file
  40  * @blkoff - file block number
  41  * @bh_result - buffer head to be mapped on
  42  * @create - indicate whether allocating the block or not when it has not
  43  *      been allocated yet.
  44  *
  45  * This function does not issue actual read request of the specified data
  46  * block. It is done by VFS.
  47  */
  48 int nilfs_get_block(struct inode *inode, sector_t blkoff,
  49                     struct buffer_head *bh_result, int create)
  50 {
  51         struct nilfs_inode_info *ii = NILFS_I(inode);
  52         __u64 blknum = 0;
  53         int err = 0, ret;
  54         struct inode *dat = nilfs_dat_inode(NILFS_I_NILFS(inode));
  55         unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;
  56
  57         down_read(&NILFS_MDT(dat)->mi_sem);
  58         ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  59         up_read(&NILFS_MDT(dat)->mi_sem);
  60         if (ret >= 0) { /* found */
  61                 map_bh(bh_result, inode->i_sb, blknum);
  62                 if (ret > 0)
  63                         bh_result->b_size = (ret << inode->i_blkbits);
  64                 goto out;
  65         }
  66         /* data block was not found */
  67         if (ret == -ENOENT && create) {
  68                 struct nilfs_transaction_info ti;
  69
  70                 bh_result->b_blocknr = 0;
  71                 err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
  72                 if (unlikely(err))
  73                         goto out;
  74                 err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
  75                                         (unsigned long)bh_result);
  76                 if (unlikely(err != 0)) {
  77                         if (err == -EEXIST) {
  78                                 /*
  79                                  * The get_block() function could be called
  80                                  * from multiple callers for an inode.
  81                                  * However, the page having this block must
  82                                  * be locked in this case.
  83                                  */
  84                                 printk(KERN_WARNING
  85                                        "nilfs_get_block: a race condition "
  86                                        "while inserting a data block. "
  87                                        "(inode number=%lu, file block "
  88                                        "offset=%llu)\n",
  89                                        inode->i_ino,
  90                                        (unsigned long long)blkoff);
  91                                 err = 0;
  92                         } else if (err == -EINVAL) {
  93                                 nilfs_error(inode->i_sb, __func__,
  94                                             "broken bmap (inode=%lu)\n",
  95                                             inode->i_ino);
  96                                 err = -EIO;
  97                         }
  98                         nilfs_transaction_abort(inode->i_sb);
  99                         goto out;
 100                 }
 101                 nilfs_mark_inode_dirty(inode);
 102                 nilfs_transaction_commit(inode->i_sb); /* never fails */
 103                 /* Error handling should be detailed */
 104                 set_buffer_new(bh_result);
 105                 map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
 106                                                       to proper value */
 107         } else if (ret == -ENOENT) {
 108                 /* not found is not error (e.g. hole); must return without
 109                    the mapped state flag. */
 110                 ;
 111         } else {
 112                 err = ret;
 113         }
 114
 115  out:
 116         return err;
 117 }
 118
 119 /**
 120  * nilfs_readpage() - implement readpage() method of nilfs_aops {}
 121  * address_space_operations.
 122  * @file - file struct of the file to be read
 123  * @page - the page to be read
 124  */
 125 static int nilfs_readpage(struct file *file, struct page *page)
 126 {
 127         return mpage_readpage(page, nilfs_get_block);
 128 }
 129
 130 /**
 131  * nilfs_readpages() - implement readpages() method of nilfs_aops {}
 132  * address_space_operations.
 133  * @file - file struct of the file to be read
 134  * @mapping - address_space struct used for reading multiple pages
 135  * @pages - the pages to be read
 136  * @nr_pages - number of pages to be read
 137  */
 138 static int nilfs_readpages(struct file *file, struct address_space *mapping,
 139                            struct list_head *pages, unsigned nr_pages)
 140 {
 141         return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
 142 }
 143
 144 static int nilfs_writepages(struct address_space *mapping,
 145                             struct writeback_control *wbc)
 146 {
 147         struct inode *inode = mapping->host;
 148         int err = 0;
 149
 150         if (wbc->sync_mode == WB_SYNC_ALL)
 151                 err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 152                                                     wbc->range_start,
 153                                                     wbc->range_end);
 154         return err;
 155 }
 156
 157 static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 158 {
 159         struct inode *inode = page->mapping->host;
 160         int err;
 161
 162         redirty_page_for_writepage(wbc, page);
 163         unlock_page(page);
 164
 165         if (wbc->sync_mode == WB_SYNC_ALL) {
 166                 err = nilfs_construct_segment(inode->i_sb);
 167                 if (unlikely(err))
 168                         return err;
 169         } else if (wbc->for_reclaim)
 170                 nilfs_flush_segment(inode->i_sb, inode->i_ino);
 171
 172         return 0;
 173 }
 174
 175 static int nilfs_set_page_dirty(struct page *page)
 176 {
 177         int ret = __set_page_dirty_buffers(page);
 178
 179         if (ret) {
 180                 struct inode *inode = page->mapping->host;
 181                 struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
 182                 unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 183
 184                 nilfs_set_file_dirty(sbi, inode, nr_dirty);
 185         }
 186         return ret;
 187 }
 188
 189 static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 190                              loff_t pos, unsigned len, unsigned flags,
 191                              struct page **pagep, void **fsdata)
 192
 193 {
 194         struct inode *inode = mapping->host;
 195         int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 196
 197         if (unlikely(err))
 198                 return err;
 199
 200         *pagep = NULL;
 201         err = block_write_begin(file, mapping, pos, len, flags, pagep,
 202                                 fsdata, nilfs_get_block);
 203         if (unlikely(err))
 204                 nilfs_transaction_abort(inode->i_sb);
 205         return err;
 206 }
 207
 208 static int nilfs_write_end(struct file *file, struct address_space *mapping,
 209                            loff_t pos, unsigned len, unsigned copied,
 210                            struct page *page, void *fsdata)
 211 {
 212         struct inode *inode = mapping->host;
 213         unsigned start = pos & (PAGE_CACHE_SIZE - 1);
 214         unsigned nr_dirty;
 215         int err;
 216
 217         nr_dirty = nilfs_page_count_clean_buffers(page, start,
 218                                                   start + copied);
 219         copied = generic_write_end(file, mapping, pos, len, copied, page,
 220                                    fsdata);
 221         nilfs_set_file_dirty(NILFS_SB(inode->i_sb), inode, nr_dirty);
 222         err = nilfs_transaction_commit(inode->i_sb);
 223         return err ? : copied;
 224 }
 225
 226 static ssize_t
 227 nilfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
 228                 loff_t offset, unsigned long nr_segs)
 229 {
 230         struct file *file = iocb->ki_filp;
 231         struct inode *inode = file->f_mapping->host;
 232         ssize_t size;
 233
 234         if (rw == WRITE)
 235                 return 0;
 236
 237         /* Needs synchronization with the cleaner */
 238         size = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 239                                   offset, nr_segs, nilfs_get_block, NULL);
 240         return size;
 241 }
 242
 243 const struct address_space_operations nilfs_aops = {
 244         .writepage              = nilfs_writepage,
 245         .readpage               = nilfs_readpage,
 246         .sync_page              = block_sync_page,
 247         .writepages             = nilfs_writepages,
 248         .set_page_dirty         = nilfs_set_page_dirty,
 249         .readpages              = nilfs_readpages,
 250         .write_begin            = nilfs_write_begin,
 251         .write_end              = nilfs_write_end,
 252         /* .releasepage         = nilfs_releasepage, */
 253         .invalidatepage         = block_invalidatepage,
 254         .direct_IO              = nilfs_direct_IO,
 255         .is_partially_uptodate  = block_is_partially_uptodate,
 256 };
 257
 258 struct inode *nilfs_new_inode(struct inode *dir, int mode)
 259 {
 260         struct super_block *sb = dir->i_sb;
 261         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 262         struct inode *inode;
 263         struct nilfs_inode_info *ii;
 264         int err = -ENOMEM;
 265         ino_t ino;
 266
 267         inode = new_inode(sb);
 268         if (unlikely(!inode))
 269                 goto failed;
 270
 271         mapping_set_gfp_mask(inode->i_mapping,
 272                              mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 273
 274         ii = NILFS_I(inode);
 275         ii->i_state = 1 << NILFS_I_NEW;
 276
 277         err = nilfs_ifile_create_inode(sbi->s_ifile, &ino, &ii->i_bh);
 278         if (unlikely(err))
 279                 goto failed_ifile_create_inode;
 280         /* reference count of i_bh inherits from nilfs_mdt_read_block() */
 281
 282         atomic_inc(&sbi->s_inodes_count);
 283         inode_init_owner(inode, dir, mode);
 284         inode->i_ino = ino;
 285         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 286
 287         if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
 288                 err = nilfs_bmap_read(ii->i_bmap, NULL);
 289                 if (err < 0)
 290                         goto failed_bmap;
 291
 292                 set_bit(NILFS_I_BMAP, &ii->i_state);
 293                 /* No lock is needed; iget() ensures it. */
 294         }
 295
 296         ii->i_flags = NILFS_I(dir)->i_flags;
 297         if (S_ISLNK(mode))
 298                 ii->i_flags &= ~(NILFS_IMMUTABLE_FL | NILFS_APPEND_FL);
 299         if (!S_ISDIR(mode))
 300                 ii->i_flags &= ~NILFS_DIRSYNC_FL;
 301
 302         /* ii->i_file_acl = 0; */
 303         /* ii->i_dir_acl = 0; */
 304         ii->i_dir_start_lookup = 0;
 305         ii->i_cno = 0;
 306         nilfs_set_inode_flags(inode);
 307         spin_lock(&sbi->s_next_gen_lock);
 308         inode->i_generation = sbi->s_next_generation++;
 309         spin_unlock(&sbi->s_next_gen_lock);
 310         insert_inode_hash(inode);
 311
 312         err = nilfs_init_acl(inode, dir);
 313         if (unlikely(err))
 314                 goto failed_acl; /* never occur. When supporting
 315                                     nilfs_init_acl(), proper cancellation of
 316                                     above jobs should be considered */
 317
 318         return inode;
 319
 320  failed_acl:
 321  failed_bmap:
 322         inode->i_nlink = 0;
 323         iput(inode);  /* raw_inode will be deleted through
 324                          generic_delete_inode() */
 325         goto failed;
 326
 327  failed_ifile_create_inode:
 328         make_bad_inode(inode);
 329         iput(inode);  /* if i_nlink == 1, generic_forget_inode() will be
 330                          called */
 331  failed:
 332         return ERR_PTR(err);
 333 }
 334
 335 void nilfs_free_inode(struct inode *inode)
 336 {
 337         struct super_block *sb = inode->i_sb;
 338         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 339
 340         clear_inode(inode);
 341         /* XXX: check error code? Is there any thing I can do? */
 342         (void) nilfs_ifile_delete_inode(sbi->s_ifile, inode->i_ino);
 343         atomic_dec(&sbi->s_inodes_count);
 344 }
 345
 346 void nilfs_set_inode_flags(struct inode *inode)
 347 {
 348         unsigned int flags = NILFS_I(inode)->i_flags;
 349
 350         inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME |
 351                             S_DIRSYNC);
 352         if (flags & NILFS_SYNC_FL)
 353                 inode->i_flags |= S_SYNC;
 354         if (flags & NILFS_APPEND_FL)
 355                 inode->i_flags |= S_APPEND;
 356         if (flags & NILFS_IMMUTABLE_FL)
 357                 inode->i_flags |= S_IMMUTABLE;
 358 #ifndef NILFS_ATIME_DISABLE
 359         if (flags & NILFS_NOATIME_FL)
 360 #endif
 361                 inode->i_flags |= S_NOATIME;
 362         if (flags & NILFS_DIRSYNC_FL)
 363                 inode->i_flags |= S_DIRSYNC;
 364         mapping_set_gfp_mask(inode->i_mapping,
 365                              mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 366 }
 367
 368 int nilfs_read_inode_common(struct inode *inode,
 369                             struct nilfs_inode *raw_inode)
 370 {
 371         struct nilfs_inode_info *ii = NILFS_I(inode);
 372         int err;
 373
 374         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
 375         inode->i_uid = (uid_t)le32_to_cpu(raw_inode->i_uid);
 376         inode->i_gid = (gid_t)le32_to_cpu(raw_inode->i_gid);
 377         inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
 378         inode->i_size = le64_to_cpu(raw_inode->i_size);
 379         inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 380         inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
 381         inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 382         inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 383         inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 384         inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 385         if (inode->i_nlink == 0 && inode->i_mode == 0)
 386                 return -EINVAL; /* this inode is deleted */
 387
 388         inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 389         ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 390 #if 0
 391         ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 392         ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 393                 0 : le32_to_cpu(raw_inode->i_dir_acl);
 394 #endif
 395         ii->i_dir_start_lookup = 0;
 396         ii->i_cno = 0;
 397         inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 398
 399         if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 400             S_ISLNK(inode->i_mode)) {
 401                 err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 402                 if (err < 0)
 403                         return err;
 404                 set_bit(NILFS_I_BMAP, &ii->i_state);
 405                 /* No lock is needed; iget() ensures it. */
 406         }
 407         return 0;
 408 }
 409
 410 static int __nilfs_read_inode(struct super_block *sb, unsigned long ino,
 411                               struct inode *inode)
 412 {
 413         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 414         struct inode *dat = nilfs_dat_inode(sbi->s_nilfs);
 415         struct buffer_head *bh;
 416         struct nilfs_inode *raw_inode;
 417         int err;
 418
 419         down_read(&NILFS_MDT(dat)->mi_sem);     /* XXX */
 420         err = nilfs_ifile_get_inode_block(sbi->s_ifile, ino, &bh);
 421         if (unlikely(err))
 422                 goto bad_inode;
 423
 424         raw_inode = nilfs_ifile_map_inode(sbi->s_ifile, ino, bh);
 425
 426         err = nilfs_read_inode_common(inode, raw_inode);
 427         if (err)
 428                 goto failed_unmap;
 429
 430         if (S_ISREG(inode->i_mode)) {
 431                 inode->i_op = &nilfs_file_inode_operations;
 432                 inode->i_fop = &nilfs_file_operations;
 433                 inode->i_mapping->a_ops = &nilfs_aops;
 434         } else if (S_ISDIR(inode->i_mode)) {
 435                 inode->i_op = &nilfs_dir_inode_operations;
 436                 inode->i_fop = &nilfs_dir_operations;
 437                 inode->i_mapping->a_ops = &nilfs_aops;
 438         } else if (S_ISLNK(inode->i_mode)) {
 439                 inode->i_op = &nilfs_symlink_inode_operations;
 440                 inode->i_mapping->a_ops = &nilfs_aops;
 441         } else {
 442                 inode->i_op = &nilfs_special_inode_operations;
 443                 init_special_inode(
 444                         inode, inode->i_mode,
 445                         huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 446         }
 447         nilfs_ifile_unmap_inode(sbi->s_ifile, ino, bh);
 448         brelse(bh);
 449         up_read(&NILFS_MDT(dat)->mi_sem);       /* XXX */
 450         nilfs_set_inode_flags(inode);
 451         return 0;
 452
 453  failed_unmap:
 454         nilfs_ifile_unmap_inode(sbi->s_ifile, ino, bh);
 455         brelse(bh);
 456
 457  bad_inode:
 458         up_read(&NILFS_MDT(dat)->mi_sem);       /* XXX */
 459         return err;
 460 }
 461
 462 struct inode *nilfs_iget(struct super_block *sb, unsigned long ino)
 463 {
 464         struct inode *inode;
 465         int err;
 466
 467         inode = iget_locked(sb, ino);
 468         if (unlikely(!inode))
 469                 return ERR_PTR(-ENOMEM);
 470         if (!(inode->i_state & I_NEW))
 471                 return inode;
 472
 473         err = __nilfs_read_inode(sb, ino, inode);
 474         if (unlikely(err)) {
 475                 iget_failed(inode);
 476                 return ERR_PTR(err);
 477         }
 478         unlock_new_inode(inode);
 479         return inode;
 480 }
 481
 482 void nilfs_write_inode_common(struct inode *inode,
 483                               struct nilfs_inode *raw_inode, int has_bmap)
 484 {
 485         struct nilfs_inode_info *ii = NILFS_I(inode);
 486
 487         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 488         raw_inode->i_uid = cpu_to_le32(inode->i_uid);
 489         raw_inode->i_gid = cpu_to_le32(inode->i_gid);
 490         raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 491         raw_inode->i_size = cpu_to_le64(inode->i_size);
 492         raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 493         raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
 494         raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 495         raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 496         raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 497
 498         raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 499         raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 500
 501         if (has_bmap)
 502                 nilfs_bmap_write(ii->i_bmap, raw_inode);
 503         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 504                 raw_inode->i_device_code =
 505                         cpu_to_le64(huge_encode_dev(inode->i_rdev));
 506         /* When extending inode, nilfs->ns_inode_size should be checked
 507            for substitutions of appended fields */
 508 }
 509
 510 void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh)
 511 {
 512         ino_t ino = inode->i_ino;
 513         struct nilfs_inode_info *ii = NILFS_I(inode);
 514         struct super_block *sb = inode->i_sb;
 515         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 516         struct nilfs_inode *raw_inode;
 517
 518         raw_inode = nilfs_ifile_map_inode(sbi->s_ifile, ino, ibh);
 519
 520         if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 521                 memset(raw_inode, 0, NILFS_MDT(sbi->s_ifile)->mi_entry_size);
 522         set_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
 523
 524         nilfs_write_inode_common(inode, raw_inode, 0);
 525                 /* XXX: call with has_bmap = 0 is a workaround to avoid
 526                    deadlock of bmap. This delays update of i_bmap to just
 527                    before writing */
 528         nilfs_ifile_unmap_inode(sbi->s_ifile, ino, ibh);
 529 }
 530
 531 #define NILFS_MAX_TRUNCATE_BLOCKS       16384  /* 64MB for 4KB block */
 532
 533 static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 534                                 unsigned long from)
 535 {
 536         unsigned long b;
 537         int ret;
 538
 539         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 540                 return;
 541  repeat:
 542         ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 543         if (ret == -ENOENT)
 544                 return;
 545         else if (ret < 0)
 546                 goto failed;
 547
 548         if (b < from)
 549                 return;
 550
 551         b -= min_t(unsigned long, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 552         ret = nilfs_bmap_truncate(ii->i_bmap, b);
 553         nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 554         if (!ret || (ret == -ENOMEM &&
 555                      nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 556                 goto repeat;
 557
 558  failed:
 559         if (ret == -EINVAL)
 560                 nilfs_error(ii->vfs_inode.i_sb, __func__,
 561                             "bmap is broken (ino=%lu)", ii->vfs_inode.i_ino);
 562         else
 563                 nilfs_warning(ii->vfs_inode.i_sb, __func__,
 564                               "failed to truncate bmap (ino=%lu, err=%d)",
 565                               ii->vfs_inode.i_ino, ret);
 566 }
 567
 568 void nilfs_truncate(struct inode *inode)
 569 {
 570         unsigned long blkoff;
 571         unsigned int blocksize;
 572         struct nilfs_transaction_info ti;
 573         struct super_block *sb = inode->i_sb;
 574         struct nilfs_inode_info *ii = NILFS_I(inode);
 575
 576         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 577                 return;
 578         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 579                 return;
 580
 581         blocksize = sb->s_blocksize;
 582         blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 583         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 584
 585         block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 586
 587         nilfs_truncate_bmap(ii, blkoff);
 588
 589         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 590         if (IS_SYNC(inode))
 591                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
 592
 593         nilfs_mark_inode_dirty(inode);
 594         nilfs_set_file_dirty(NILFS_SB(sb), inode, 0);
 595         nilfs_transaction_commit(sb);
 596         /* May construct a logical segment and may fail in sync mode.
 597            But truncate has no return value. */
 598 }
 599
 600 void nilfs_delete_inode(struct inode *inode)
 601 {
 602         struct nilfs_transaction_info ti;
 603         struct super_block *sb = inode->i_sb;
 604         struct nilfs_inode_info *ii = NILFS_I(inode);
 605
 606         if (unlikely(is_bad_inode(inode))) {
 607                 if (inode->i_data.nrpages)
 608                         truncate_inode_pages(&inode->i_data, 0);
 609                 clear_inode(inode);
 610                 return;
 611         }
 612         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 613
 614         if (inode->i_data.nrpages)
 615                 truncate_inode_pages(&inode->i_data, 0);
 616
 617         nilfs_truncate_bmap(ii, 0);
 618         nilfs_mark_inode_dirty(inode);
 619         nilfs_free_inode(inode);
 620         /* nilfs_free_inode() marks inode buffer dirty */
 621         if (IS_SYNC(inode))
 622                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
 623         nilfs_transaction_commit(sb);
 624         /* May construct a logical segment and may fail in sync mode.
 625            But delete_inode has no return value. */
 626 }
 627
 628 int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 629 {
 630         struct nilfs_transaction_info ti;
 631         struct inode *inode = dentry->d_inode;
 632         struct super_block *sb = inode->i_sb;
 633         int err;
 634
 635         err = inode_change_ok(inode, iattr);
 636         if (err)
 637                 return err;
 638
 639         err = nilfs_transaction_begin(sb, &ti, 0);
 640         if (unlikely(err))
 641                 return err;
 642         err = inode_setattr(inode, iattr);
 643         if (!err && (iattr->ia_valid & ATTR_MODE))
 644                 err = nilfs_acl_chmod(inode);
 645         if (likely(!err))
 646                 err = nilfs_transaction_commit(sb);
 647         else
 648                 nilfs_transaction_abort(sb);
 649
 650         return err;
 651 }
 652
 653 int nilfs_load_inode_block(struct nilfs_sb_info *sbi, struct inode *inode,
 654                            struct buffer_head **pbh)
 655 {
 656         struct nilfs_inode_info *ii = NILFS_I(inode);
 657         int err;
 658
 659         spin_lock(&sbi->s_inode_lock);
 660         if (ii->i_bh == NULL) {
 661                 spin_unlock(&sbi->s_inode_lock);
 662                 err = nilfs_ifile_get_inode_block(sbi->s_ifile, inode->i_ino,
 663                                                   pbh);
 664                 if (unlikely(err))
 665                         return err;
 666                 spin_lock(&sbi->s_inode_lock);
 667                 if (ii->i_bh == NULL)
 668                         ii->i_bh = *pbh;
 669                 else {
 670                         brelse(*pbh);
 671                         *pbh = ii->i_bh;
 672                 }
 673         } else
 674                 *pbh = ii->i_bh;
 675
 676         get_bh(*pbh);
 677         spin_unlock(&sbi->s_inode_lock);
 678         return 0;
 679 }
 680
 681 int nilfs_inode_dirty(struct inode *inode)
 682 {
 683         struct nilfs_inode_info *ii = NILFS_I(inode);
 684         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
 685         int ret = 0;
 686
 687         if (!list_empty(&ii->i_dirty)) {
 688                 spin_lock(&sbi->s_inode_lock);
 689                 ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
 690                         test_bit(NILFS_I_BUSY, &ii->i_state);
 691                 spin_unlock(&sbi->s_inode_lock);
 692         }
 693         return ret;
 694 }
 695
 696 int nilfs_set_file_dirty(struct nilfs_sb_info *sbi, struct inode *inode,
 697                          unsigned nr_dirty)
 698 {
 699         struct nilfs_inode_info *ii = NILFS_I(inode);
 700
 701         atomic_add(nr_dirty, &sbi->s_nilfs->ns_ndirtyblks);
 702
 703         if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
 704                 return 0;
 705
 706         spin_lock(&sbi->s_inode_lock);
 707         if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
 708             !test_bit(NILFS_I_BUSY, &ii->i_state)) {
 709                 /* Because this routine may race with nilfs_dispose_list(),
 710                    we have to check NILFS_I_QUEUED here, too. */
 711                 if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
 712                         /* This will happen when somebody is freeing
 713                            this inode. */
 714                         nilfs_warning(sbi->s_super, __func__,
 715                                       "cannot get inode (ino=%lu)\n",
 716                                       inode->i_ino);
 717                         spin_unlock(&sbi->s_inode_lock);
 718                         return -EINVAL; /* NILFS_I_DIRTY may remain for
 719                                            freeing inode */
 720                 }
 721                 list_del(&ii->i_dirty);
 722                 list_add_tail(&ii->i_dirty, &sbi->s_dirty_files);
 723                 set_bit(NILFS_I_QUEUED, &ii->i_state);
 724         }
 725         spin_unlock(&sbi->s_inode_lock);
 726         return 0;
 727 }
 728
 729 int nilfs_mark_inode_dirty(struct inode *inode)
 730 {
 731         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
 732         struct buffer_head *ibh;
 733         int err;
 734
 735         err = nilfs_load_inode_block(sbi, inode, &ibh);
 736         if (unlikely(err)) {
 737                 nilfs_warning(inode->i_sb, __func__,
 738                               "failed to reget inode block.\n");
 739                 return err;
 740         }
 741         nilfs_update_inode(inode, ibh);
 742         nilfs_mdt_mark_buffer_dirty(ibh);
 743         nilfs_mdt_mark_dirty(sbi->s_ifile);
 744         brelse(ibh);
 745         return 0;
 746 }
 747
 748 /**
 749  * nilfs_dirty_inode - reflect changes on given inode to an inode block.
 750  * @inode: inode of the file to be registered.
 751  *
 752  * nilfs_dirty_inode() loads a inode block containing the specified
 753  * @inode and copies data from a nilfs_inode to a corresponding inode
 754  * entry in the inode block. This operation is excluded from the segment
 755  * construction. This function can be called both as a single operation
 756  * and as a part of indivisible file operations.
 757  */
 758 void nilfs_dirty_inode(struct inode *inode)
 759 {
 760         struct nilfs_transaction_info ti;
 761
 762         if (is_bad_inode(inode)) {
 763                 nilfs_warning(inode->i_sb, __func__,
 764                               "tried to mark bad_inode dirty. ignored.\n");
 765                 dump_stack();
 766                 return;
 767         }
 768         nilfs_transaction_begin(inode->i_sb, &ti, 0);
 769         nilfs_mark_inode_dirty(inode);
 770         nilfs_transaction_commit(inode->i_sb); /* never fails */
 771 }