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 "btnode.h"
  31 #include "segment.h"
  32 #include "page.h"
  33 #include "mdt.h"
  34 #include "cpfile.h"
  35 #include "ifile.h"
  36
  37 struct nilfs_iget_args {
  38         u64 ino;
  39         __u64 cno;
  40         struct nilfs_root *root;
  41         int for_gc;
  42 };
  43
  44 /**
  45  * nilfs_get_block() - get a file block on the filesystem (callback function)
  46  * @inode - inode struct of the target file
  47  * @blkoff - file block number
  48  * @bh_result - buffer head to be mapped on
  49  * @create - indicate whether allocating the block or not when it has not
  50  *      been allocated yet.
  51  *
  52  * This function does not issue actual read request of the specified data
  53  * block. It is done by VFS.
  54  */
  55 int nilfs_get_block(struct inode *inode, sector_t blkoff,
  56                     struct buffer_head *bh_result, int create)
  57 {
  58         struct nilfs_inode_info *ii = NILFS_I(inode);
  59         __u64 blknum = 0;
  60         int err = 0, ret;
  61         struct inode *dat = NILFS_I_NILFS(inode)->ns_dat;
  62         unsigned maxblocks = bh_result->b_size >> inode->i_blkbits;
  63
  64         down_read(&NILFS_MDT(dat)->mi_sem);
  65         ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  66         up_read(&NILFS_MDT(dat)->mi_sem);
  67         if (ret >= 0) { /* found */
  68                 map_bh(bh_result, inode->i_sb, blknum);
  69                 if (ret > 0)
  70                         bh_result->b_size = (ret << inode->i_blkbits);
  71                 goto out;
  72         }
  73         /* data block was not found */
  74         if (ret == -ENOENT && create) {
  75                 struct nilfs_transaction_info ti;
  76
  77                 bh_result->b_blocknr = 0;
  78                 err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
  79                 if (unlikely(err))
  80                         goto out;
  81                 err = nilfs_bmap_insert(ii->i_bmap, (unsigned long)blkoff,
  82                                         (unsigned long)bh_result);
  83                 if (unlikely(err != 0)) {
  84                         if (err == -EEXIST) {
  85                                 /*
  86                                  * The get_block() function could be called
  87                                  * from multiple callers for an inode.
  88                                  * However, the page having this block must
  89                                  * be locked in this case.
  90                                  */
  91                                 printk(KERN_WARNING
  92                                        "nilfs_get_block: a race condition "
  93                                        "while inserting a data block. "
  94                                        "(inode number=%lu, file block "
  95                                        "offset=%llu)\n",
  96                                        inode->i_ino,
  97                                        (unsigned long long)blkoff);
  98                                 err = 0;
  99                         }
 100                         nilfs_transaction_abort(inode->i_sb);
 101                         goto out;
 102                 }
 103                 nilfs_mark_inode_dirty(inode);
 104                 nilfs_transaction_commit(inode->i_sb); /* never fails */
 105                 /* Error handling should be detailed */
 106                 set_buffer_new(bh_result);
 107                 set_buffer_delay(bh_result);
 108                 map_bh(bh_result, inode->i_sb, 0); /* dbn must be changed
 109                                                       to proper value */
 110         } else if (ret == -ENOENT) {
 111                 /* not found is not error (e.g. hole); must return without
 112                    the mapped state flag. */
 113                 ;
 114         } else {
 115                 err = ret;
 116         }
 117
 118  out:
 119         return err;
 120 }
 121
 122 /**
 123  * nilfs_readpage() - implement readpage() method of nilfs_aops {}
 124  * address_space_operations.
 125  * @file - file struct of the file to be read
 126  * @page - the page to be read
 127  */
 128 static int nilfs_readpage(struct file *file, struct page *page)
 129 {
 130         return mpage_readpage(page, nilfs_get_block);
 131 }
 132
 133 /**
 134  * nilfs_readpages() - implement readpages() method of nilfs_aops {}
 135  * address_space_operations.
 136  * @file - file struct of the file to be read
 137  * @mapping - address_space struct used for reading multiple pages
 138  * @pages - the pages to be read
 139  * @nr_pages - number of pages to be read
 140  */
 141 static int nilfs_readpages(struct file *file, struct address_space *mapping,
 142                            struct list_head *pages, unsigned nr_pages)
 143 {
 144         return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
 145 }
 146
 147 static int nilfs_writepages(struct address_space *mapping,
 148                             struct writeback_control *wbc)
 149 {
 150         struct inode *inode = mapping->host;
 151         int err = 0;
 152
 153         if (wbc->sync_mode == WB_SYNC_ALL)
 154                 err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 155                                                     wbc->range_start,
 156                                                     wbc->range_end);
 157         return err;
 158 }
 159
 160 static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 161 {
 162         struct inode *inode = page->mapping->host;
 163         int err;
 164
 165         redirty_page_for_writepage(wbc, page);
 166         unlock_page(page);
 167
 168         if (wbc->sync_mode == WB_SYNC_ALL) {
 169                 err = nilfs_construct_segment(inode->i_sb);
 170                 if (unlikely(err))
 171                         return err;
 172         } else if (wbc->for_reclaim)
 173                 nilfs_flush_segment(inode->i_sb, inode->i_ino);
 174
 175         return 0;
 176 }
 177
 178 static int nilfs_set_page_dirty(struct page *page)
 179 {
 180         int ret = __set_page_dirty_buffers(page);
 181
 182         if (ret) {
 183                 struct inode *inode = page->mapping->host;
 184                 unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 185
 186                 nilfs_set_file_dirty(inode, nr_dirty);
 187         }
 188         return ret;
 189 }
 190
 191 static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 192                              loff_t pos, unsigned len, unsigned flags,
 193                              struct page **pagep, void **fsdata)
 194
 195 {
 196         struct inode *inode = mapping->host;
 197         int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 198
 199         if (unlikely(err))
 200                 return err;
 201
 202         err = block_write_begin(mapping, pos, len, flags, pagep,
 203                                 nilfs_get_block);
 204         if (unlikely(err)) {
 205                 loff_t isize = mapping->host->i_size;
 206                 if (pos + len > isize)
 207                         vmtruncate(mapping->host, isize);
 208
 209                 nilfs_transaction_abort(inode->i_sb);
 210         }
 211         return err;
 212 }
 213
 214 static int nilfs_write_end(struct file *file, struct address_space *mapping,
 215                            loff_t pos, unsigned len, unsigned copied,
 216                            struct page *page, void *fsdata)
 217 {
 218         struct inode *inode = mapping->host;
 219         unsigned start = pos & (PAGE_CACHE_SIZE - 1);
 220         unsigned nr_dirty;
 221         int err;
 222
 223         nr_dirty = nilfs_page_count_clean_buffers(page, start,
 224                                                   start + copied);
 225         copied = generic_write_end(file, mapping, pos, len, copied, page,
 226                                    fsdata);
 227         nilfs_set_file_dirty(inode, nr_dirty);
 228         err = nilfs_transaction_commit(inode->i_sb);
 229         return err ? : copied;
 230 }
 231
 232 static ssize_t
 233 nilfs_direct_IO(int rw, struct kiocb *iocb, const struct iovec *iov,
 234                 loff_t offset, unsigned long nr_segs)
 235 {
 236         struct file *file = iocb->ki_filp;
 237         struct inode *inode = file->f_mapping->host;
 238         ssize_t size;
 239
 240         if (rw == WRITE)
 241                 return 0;
 242
 243         /* Needs synchronization with the cleaner */
 244         size = blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
 245                                   offset, nr_segs, nilfs_get_block, NULL);
 246
 247         /*
 248          * In case of error extending write may have instantiated a few
 249          * blocks outside i_size. Trim these off again.
 250          */
 251         if (unlikely((rw & WRITE) && size < 0)) {
 252                 loff_t isize = i_size_read(inode);
 253                 loff_t end = offset + iov_length(iov, nr_segs);
 254
 255                 if (end > isize)
 256                         vmtruncate(inode, isize);
 257         }
 258
 259         return size;
 260 }
 261
 262 const struct address_space_operations nilfs_aops = {
 263         .writepage              = nilfs_writepage,
 264         .readpage               = nilfs_readpage,
 265         .sync_page              = block_sync_page,
 266         .writepages             = nilfs_writepages,
 267         .set_page_dirty         = nilfs_set_page_dirty,
 268         .readpages              = nilfs_readpages,
 269         .write_begin            = nilfs_write_begin,
 270         .write_end              = nilfs_write_end,
 271         /* .releasepage         = nilfs_releasepage, */
 272         .invalidatepage         = block_invalidatepage,
 273         .direct_IO              = nilfs_direct_IO,
 274         .is_partially_uptodate  = block_is_partially_uptodate,
 275 };
 276
 277 struct inode *nilfs_new_inode(struct inode *dir, int mode)
 278 {
 279         struct super_block *sb = dir->i_sb;
 280         struct nilfs_sb_info *sbi = NILFS_SB(sb);
 281         struct inode *inode;
 282         struct nilfs_inode_info *ii;
 283         struct nilfs_root *root;
 284         int err = -ENOMEM;
 285         ino_t ino;
 286
 287         inode = new_inode(sb);
 288         if (unlikely(!inode))
 289                 goto failed;
 290
 291         mapping_set_gfp_mask(inode->i_mapping,
 292                              mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 293
 294         root = NILFS_I(dir)->i_root;
 295         ii = NILFS_I(inode);
 296         ii->i_state = 1 << NILFS_I_NEW;
 297         ii->i_root = root;
 298
 299         err = nilfs_ifile_create_inode(root->ifile, &ino, &ii->i_bh);
 300         if (unlikely(err))
 301                 goto failed_ifile_create_inode;
 302         /* reference count of i_bh inherits from nilfs_mdt_read_block() */
 303
 304         atomic_inc(&root->inodes_count);
 305         inode_init_owner(inode, dir, mode);
 306         inode->i_ino = ino;
 307         inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 308
 309         if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
 310                 err = nilfs_bmap_read(ii->i_bmap, NULL);
 311                 if (err < 0)
 312                         goto failed_bmap;
 313
 314                 set_bit(NILFS_I_BMAP, &ii->i_state);
 315                 /* No lock is needed; iget() ensures it. */
 316         }
 317
 318         ii->i_flags = NILFS_I(dir)->i_flags;
 319         if (S_ISLNK(mode))
 320                 ii->i_flags &= ~(NILFS_IMMUTABLE_FL | NILFS_APPEND_FL);
 321         if (!S_ISDIR(mode))
 322                 ii->i_flags &= ~NILFS_DIRSYNC_FL;
 323
 324         /* ii->i_file_acl = 0; */
 325         /* ii->i_dir_acl = 0; */
 326         ii->i_dir_start_lookup = 0;
 327         nilfs_set_inode_flags(inode);
 328         spin_lock(&sbi->s_next_gen_lock);
 329         inode->i_generation = sbi->s_next_generation++;
 330         spin_unlock(&sbi->s_next_gen_lock);
 331         insert_inode_hash(inode);
 332
 333         err = nilfs_init_acl(inode, dir);
 334         if (unlikely(err))
 335                 goto failed_acl; /* never occur. When supporting
 336                                     nilfs_init_acl(), proper cancellation of
 337                                     above jobs should be considered */
 338
 339         return inode;
 340
 341  failed_acl:
 342  failed_bmap:
 343         inode->i_nlink = 0;
 344         iput(inode);  /* raw_inode will be deleted through
 345                          generic_delete_inode() */
 346         goto failed;
 347
 348  failed_ifile_create_inode:
 349         make_bad_inode(inode);
 350         iput(inode);  /* if i_nlink == 1, generic_forget_inode() will be
 351                          called */
 352  failed:
 353         return ERR_PTR(err);
 354 }
 355
 356 void nilfs_set_inode_flags(struct inode *inode)
 357 {
 358         unsigned int flags = NILFS_I(inode)->i_flags;
 359
 360         inode->i_flags &= ~(S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME |
 361                             S_DIRSYNC);
 362         if (flags & NILFS_SYNC_FL)
 363                 inode->i_flags |= S_SYNC;
 364         if (flags & NILFS_APPEND_FL)
 365                 inode->i_flags |= S_APPEND;
 366         if (flags & NILFS_IMMUTABLE_FL)
 367                 inode->i_flags |= S_IMMUTABLE;
 368 #ifndef NILFS_ATIME_DISABLE
 369         if (flags & NILFS_NOATIME_FL)
 370 #endif
 371                 inode->i_flags |= S_NOATIME;
 372         if (flags & NILFS_DIRSYNC_FL)
 373                 inode->i_flags |= S_DIRSYNC;
 374         mapping_set_gfp_mask(inode->i_mapping,
 375                              mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 376 }
 377
 378 int nilfs_read_inode_common(struct inode *inode,
 379                             struct nilfs_inode *raw_inode)
 380 {
 381         struct nilfs_inode_info *ii = NILFS_I(inode);
 382         int err;
 383
 384         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
 385         inode->i_uid = (uid_t)le32_to_cpu(raw_inode->i_uid);
 386         inode->i_gid = (gid_t)le32_to_cpu(raw_inode->i_gid);
 387         inode->i_nlink = le16_to_cpu(raw_inode->i_links_count);
 388         inode->i_size = le64_to_cpu(raw_inode->i_size);
 389         inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 390         inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
 391         inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 392         inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 393         inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 394         inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 395         if (inode->i_nlink == 0 && inode->i_mode == 0)
 396                 return -EINVAL; /* this inode is deleted */
 397
 398         inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 399         ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 400 #if 0
 401         ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 402         ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 403                 0 : le32_to_cpu(raw_inode->i_dir_acl);
 404 #endif
 405         ii->i_dir_start_lookup = 0;
 406         inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 407
 408         if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 409             S_ISLNK(inode->i_mode)) {
 410                 err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 411                 if (err < 0)
 412                         return err;
 413                 set_bit(NILFS_I_BMAP, &ii->i_state);
 414                 /* No lock is needed; iget() ensures it. */
 415         }
 416         return 0;
 417 }
 418
 419 static int __nilfs_read_inode(struct super_block *sb,
 420                               struct nilfs_root *root, unsigned long ino,
 421                               struct inode *inode)
 422 {
 423         struct the_nilfs *nilfs = NILFS_SB(sb)->s_nilfs;
 424         struct buffer_head *bh;
 425         struct nilfs_inode *raw_inode;
 426         int err;
 427
 428         down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 429         err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
 430         if (unlikely(err))
 431                 goto bad_inode;
 432
 433         raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
 434
 435         err = nilfs_read_inode_common(inode, raw_inode);
 436         if (err)
 437                 goto failed_unmap;
 438
 439         if (S_ISREG(inode->i_mode)) {
 440                 inode->i_op = &nilfs_file_inode_operations;
 441                 inode->i_fop = &nilfs_file_operations;
 442                 inode->i_mapping->a_ops = &nilfs_aops;
 443         } else if (S_ISDIR(inode->i_mode)) {
 444                 inode->i_op = &nilfs_dir_inode_operations;
 445                 inode->i_fop = &nilfs_dir_operations;
 446                 inode->i_mapping->a_ops = &nilfs_aops;
 447         } else if (S_ISLNK(inode->i_mode)) {
 448                 inode->i_op = &nilfs_symlink_inode_operations;
 449                 inode->i_mapping->a_ops = &nilfs_aops;
 450         } else {
 451                 inode->i_op = &nilfs_special_inode_operations;
 452                 init_special_inode(
 453                         inode, inode->i_mode,
 454                         huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 455         }
 456         nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 457         brelse(bh);
 458         up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 459         nilfs_set_inode_flags(inode);
 460         return 0;
 461
 462  failed_unmap:
 463         nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 464         brelse(bh);
 465
 466  bad_inode:
 467         up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 468         return err;
 469 }
 470
 471 static int nilfs_iget_test(struct inode *inode, void *opaque)
 472 {
 473         struct nilfs_iget_args *args = opaque;
 474         struct nilfs_inode_info *ii;
 475
 476         if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
 477                 return 0;
 478
 479         ii = NILFS_I(inode);
 480         if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
 481                 return !args->for_gc;
 482
 483         return args->for_gc && args->cno == ii->i_cno;
 484 }
 485
 486 static int nilfs_iget_set(struct inode *inode, void *opaque)
 487 {
 488         struct nilfs_iget_args *args = opaque;
 489
 490         inode->i_ino = args->ino;
 491         if (args->for_gc) {
 492                 NILFS_I(inode)->i_state = 1 << NILFS_I_GCINODE;
 493                 NILFS_I(inode)->i_cno = args->cno;
 494                 NILFS_I(inode)->i_root = NULL;
 495         } else {
 496                 if (args->root && args->ino == NILFS_ROOT_INO)
 497                         nilfs_get_root(args->root);
 498                 NILFS_I(inode)->i_root = args->root;
 499         }
 500         return 0;
 501 }
 502
 503 struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
 504                             unsigned long ino)
 505 {
 506         struct nilfs_iget_args args = {
 507                 .ino = ino, .root = root, .cno = 0, .for_gc = 0
 508         };
 509
 510         return ilookup5(sb, ino, nilfs_iget_test, &args);
 511 }
 512
 513 struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
 514                                 unsigned long ino)
 515 {
 516         struct nilfs_iget_args args = {
 517                 .ino = ino, .root = root, .cno = 0, .for_gc = 0
 518         };
 519
 520         return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 521 }
 522
 523 struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
 524                          unsigned long ino)
 525 {
 526         struct inode *inode;
 527         int err;
 528
 529         inode = nilfs_iget_locked(sb, root, ino);
 530         if (unlikely(!inode))
 531                 return ERR_PTR(-ENOMEM);
 532         if (!(inode->i_state & I_NEW))
 533                 return inode;
 534
 535         err = __nilfs_read_inode(sb, root, ino, inode);
 536         if (unlikely(err)) {
 537                 iget_failed(inode);
 538                 return ERR_PTR(err);
 539         }
 540         unlock_new_inode(inode);
 541         return inode;
 542 }
 543
 544 struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
 545                                 __u64 cno)
 546 {
 547         struct nilfs_iget_args args = {
 548                 .ino = ino, .root = NULL, .cno = cno, .for_gc = 1
 549         };
 550         struct inode *inode;
 551         int err;
 552
 553         inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 554         if (unlikely(!inode))
 555                 return ERR_PTR(-ENOMEM);
 556         if (!(inode->i_state & I_NEW))
 557                 return inode;
 558
 559         err = nilfs_init_gcinode(inode);
 560         if (unlikely(err)) {
 561                 iget_failed(inode);
 562                 return ERR_PTR(err);
 563         }
 564         unlock_new_inode(inode);
 565         return inode;
 566 }
 567
 568 void nilfs_write_inode_common(struct inode *inode,
 569                               struct nilfs_inode *raw_inode, int has_bmap)
 570 {
 571         struct nilfs_inode_info *ii = NILFS_I(inode);
 572
 573         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 574         raw_inode->i_uid = cpu_to_le32(inode->i_uid);
 575         raw_inode->i_gid = cpu_to_le32(inode->i_gid);
 576         raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 577         raw_inode->i_size = cpu_to_le64(inode->i_size);
 578         raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 579         raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
 580         raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 581         raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 582         raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 583
 584         raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 585         raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 586
 587         if (has_bmap)
 588                 nilfs_bmap_write(ii->i_bmap, raw_inode);
 589         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 590                 raw_inode->i_device_code =
 591                         cpu_to_le64(huge_encode_dev(inode->i_rdev));
 592         /* When extending inode, nilfs->ns_inode_size should be checked
 593            for substitutions of appended fields */
 594 }
 595
 596 void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh)
 597 {
 598         ino_t ino = inode->i_ino;
 599         struct nilfs_inode_info *ii = NILFS_I(inode);
 600         struct inode *ifile = ii->i_root->ifile;
 601         struct nilfs_inode *raw_inode;
 602
 603         raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
 604
 605         if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 606                 memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
 607         set_bit(NILFS_I_INODE_DIRTY, &ii->i_state);
 608
 609         nilfs_write_inode_common(inode, raw_inode, 0);
 610                 /* XXX: call with has_bmap = 0 is a workaround to avoid
 611                    deadlock of bmap. This delays update of i_bmap to just
 612                    before writing */
 613         nilfs_ifile_unmap_inode(ifile, ino, ibh);
 614 }
 615
 616 #define NILFS_MAX_TRUNCATE_BLOCKS       16384  /* 64MB for 4KB block */
 617
 618 static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 619                                 unsigned long from)
 620 {
 621         unsigned long b;
 622         int ret;
 623
 624         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 625                 return;
 626 repeat:
 627         ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 628         if (ret == -ENOENT)
 629                 return;
 630         else if (ret < 0)
 631                 goto failed;
 632
 633         if (b < from)
 634                 return;
 635
 636         b -= min_t(unsigned long, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 637         ret = nilfs_bmap_truncate(ii->i_bmap, b);
 638         nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 639         if (!ret || (ret == -ENOMEM &&
 640                      nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 641                 goto repeat;
 642
 643 failed:
 644         nilfs_warning(ii->vfs_inode.i_sb, __func__,
 645                       "failed to truncate bmap (ino=%lu, err=%d)",
 646                       ii->vfs_inode.i_ino, ret);
 647 }
 648
 649 void nilfs_truncate(struct inode *inode)
 650 {
 651         unsigned long blkoff;
 652         unsigned int blocksize;
 653         struct nilfs_transaction_info ti;
 654         struct super_block *sb = inode->i_sb;
 655         struct nilfs_inode_info *ii = NILFS_I(inode);
 656
 657         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 658                 return;
 659         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 660                 return;
 661
 662         blocksize = sb->s_blocksize;
 663         blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 664         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 665
 666         block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 667
 668         nilfs_truncate_bmap(ii, blkoff);
 669
 670         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
 671         if (IS_SYNC(inode))
 672                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
 673
 674         nilfs_mark_inode_dirty(inode);
 675         nilfs_set_file_dirty(inode, 0);
 676         nilfs_transaction_commit(sb);
 677         /* May construct a logical segment and may fail in sync mode.
 678            But truncate has no return value. */
 679 }
 680
 681 static void nilfs_clear_inode(struct inode *inode)
 682 {
 683         struct nilfs_inode_info *ii = NILFS_I(inode);
 684         struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 685
 686         /*
 687          * Free resources allocated in nilfs_read_inode(), here.
 688          */
 689         BUG_ON(!list_empty(&ii->i_dirty));
 690         brelse(ii->i_bh);
 691         ii->i_bh = NULL;
 692
 693         if (mdi && mdi->mi_palloc_cache)
 694                 nilfs_palloc_destroy_cache(inode);
 695
 696         if (test_bit(NILFS_I_BMAP, &ii->i_state))
 697                 nilfs_bmap_clear(ii->i_bmap);
 698
 699         nilfs_btnode_cache_clear(&ii->i_btnode_cache);
 700
 701         if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
 702                 nilfs_put_root(ii->i_root);
 703 }
 704
 705 void nilfs_evict_inode(struct inode *inode)
 706 {
 707         struct nilfs_transaction_info ti;
 708         struct super_block *sb = inode->i_sb;
 709         struct nilfs_inode_info *ii = NILFS_I(inode);
 710
 711         if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
 712                 if (inode->i_data.nrpages)
 713                         truncate_inode_pages(&inode->i_data, 0);
 714                 end_writeback(inode);
 715                 nilfs_clear_inode(inode);
 716                 return;
 717         }
 718         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 719
 720         if (inode->i_data.nrpages)
 721                 truncate_inode_pages(&inode->i_data, 0);
 722
 723         /* TODO: some of the following operations may fail.  */
 724         nilfs_truncate_bmap(ii, 0);
 725         nilfs_mark_inode_dirty(inode);
 726         end_writeback(inode);
 727
 728         nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
 729         atomic_dec(&ii->i_root->inodes_count);
 730
 731         nilfs_clear_inode(inode);
 732
 733         if (IS_SYNC(inode))
 734                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
 735         nilfs_transaction_commit(sb);
 736         /* May construct a logical segment and may fail in sync mode.
 737            But delete_inode has no return value. */
 738 }
 739
 740 int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 741 {
 742         struct nilfs_transaction_info ti;
 743         struct inode *inode = dentry->d_inode;
 744         struct super_block *sb = inode->i_sb;
 745         int err;
 746
 747         err = inode_change_ok(inode, iattr);
 748         if (err)
 749                 return err;
 750
 751         err = nilfs_transaction_begin(sb, &ti, 0);
 752         if (unlikely(err))
 753                 return err;
 754
 755         if ((iattr->ia_valid & ATTR_SIZE) &&
 756             iattr->ia_size != i_size_read(inode)) {
 757                 err = vmtruncate(inode, iattr->ia_size);
 758                 if (unlikely(err))
 759                         goto out_err;
 760         }
 761
 762         setattr_copy(inode, iattr);
 763         mark_inode_dirty(inode);
 764
 765         if (iattr->ia_valid & ATTR_MODE) {
 766                 err = nilfs_acl_chmod(inode);
 767                 if (unlikely(err))
 768                         goto out_err;
 769         }
 770
 771         return nilfs_transaction_commit(sb);
 772
 773 out_err:
 774         nilfs_transaction_abort(sb);
 775         return err;
 776 }
 777
 778 int nilfs_permission(struct inode *inode, int mask, unsigned int flags)
 779 {
 780         struct nilfs_root *root;
 781
 782         if (flags & IPERM_FLAG_RCU)
 783                 return -ECHILD;
 784
 785         root = NILFS_I(inode)->i_root;
 786         if ((mask & MAY_WRITE) && root &&
 787             root->cno != NILFS_CPTREE_CURRENT_CNO)
 788                 return -EROFS; /* snapshot is not writable */
 789
 790         return generic_permission(inode, mask, flags, NULL);
 791 }
 792
 793 int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
 794 {
 795         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
 796         struct nilfs_inode_info *ii = NILFS_I(inode);
 797         int err;
 798
 799         spin_lock(&sbi->s_inode_lock);
 800         if (ii->i_bh == NULL) {
 801                 spin_unlock(&sbi->s_inode_lock);
 802                 err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
 803                                                   inode->i_ino, pbh);
 804                 if (unlikely(err))
 805                         return err;
 806                 spin_lock(&sbi->s_inode_lock);
 807                 if (ii->i_bh == NULL)
 808                         ii->i_bh = *pbh;
 809                 else {
 810                         brelse(*pbh);
 811                         *pbh = ii->i_bh;
 812                 }
 813         } else
 814                 *pbh = ii->i_bh;
 815
 816         get_bh(*pbh);
 817         spin_unlock(&sbi->s_inode_lock);
 818         return 0;
 819 }
 820
 821 int nilfs_inode_dirty(struct inode *inode)
 822 {
 823         struct nilfs_inode_info *ii = NILFS_I(inode);
 824         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
 825         int ret = 0;
 826
 827         if (!list_empty(&ii->i_dirty)) {
 828                 spin_lock(&sbi->s_inode_lock);
 829                 ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
 830                         test_bit(NILFS_I_BUSY, &ii->i_state);
 831                 spin_unlock(&sbi->s_inode_lock);
 832         }
 833         return ret;
 834 }
 835
 836 int nilfs_set_file_dirty(struct inode *inode, unsigned nr_dirty)
 837 {
 838         struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
 839         struct nilfs_inode_info *ii = NILFS_I(inode);
 840
 841         atomic_add(nr_dirty, &sbi->s_nilfs->ns_ndirtyblks);
 842
 843         if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
 844                 return 0;
 845
 846         spin_lock(&sbi->s_inode_lock);
 847         if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
 848             !test_bit(NILFS_I_BUSY, &ii->i_state)) {
 849                 /* Because this routine may race with nilfs_dispose_list(),
 850                    we have to check NILFS_I_QUEUED here, too. */
 851                 if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
 852                         /* This will happen when somebody is freeing
 853                            this inode. */
 854                         nilfs_warning(sbi->s_super, __func__,
 855                                       "cannot get inode (ino=%lu)\n",
 856                                       inode->i_ino);
 857                         spin_unlock(&sbi->s_inode_lock);
 858                         return -EINVAL; /* NILFS_I_DIRTY may remain for
 859                                            freeing inode */
 860                 }
 861                 list_del(&ii->i_dirty);
 862                 list_add_tail(&ii->i_dirty, &sbi->s_dirty_files);
 863                 set_bit(NILFS_I_QUEUED, &ii->i_state);
 864         }
 865         spin_unlock(&sbi->s_inode_lock);
 866         return 0;
 867 }
 868
 869 int nilfs_mark_inode_dirty(struct inode *inode)
 870 {
 871         struct buffer_head *ibh;
 872         int err;
 873
 874         err = nilfs_load_inode_block(inode, &ibh);
 875         if (unlikely(err)) {
 876                 nilfs_warning(inode->i_sb, __func__,
 877                               "failed to reget inode block.\n");
 878                 return err;
 879         }
 880         nilfs_update_inode(inode, ibh);
 881         nilfs_mdt_mark_buffer_dirty(ibh);
 882         nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
 883         brelse(ibh);
 884         return 0;
 885 }
 886
 887 /**
 888  * nilfs_dirty_inode - reflect changes on given inode to an inode block.
 889  * @inode: inode of the file to be registered.
 890  *
 891  * nilfs_dirty_inode() loads a inode block containing the specified
 892  * @inode and copies data from a nilfs_inode to a corresponding inode
 893  * entry in the inode block. This operation is excluded from the segment
 894  * construction. This function can be called both as a single operation
 895  * and as a part of indivisible file operations.
 896  */
 897 void nilfs_dirty_inode(struct inode *inode)
 898 {
 899         struct nilfs_transaction_info ti;
 900         struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 901
 902         if (is_bad_inode(inode)) {
 903                 nilfs_warning(inode->i_sb, __func__,
 904                               "tried to mark bad_inode dirty. ignored.\n");
 905                 dump_stack();
 906                 return;
 907         }
 908         if (mdi) {
 909                 nilfs_mdt_mark_dirty(inode);
 910                 return;
 911         }
 912         nilfs_transaction_begin(inode->i_sb, &ti, 0);
 913         nilfs_mark_inode_dirty(inode);
 914         nilfs_transaction_commit(inode->i_sb); /* never fails */
 915 }
 916
 917 int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 918                  __u64 start, __u64 len)
 919 {
 920         struct the_nilfs *nilfs = NILFS_I_NILFS(inode);
 921         __u64 logical = 0, phys = 0, size = 0;
 922         __u32 flags = 0;
 923         loff_t isize;
 924         sector_t blkoff, end_blkoff;
 925         sector_t delalloc_blkoff;
 926         unsigned long delalloc_blklen;
 927         unsigned int blkbits = inode->i_blkbits;
 928         int ret, n;
 929
 930         ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
 931         if (ret)
 932                 return ret;
 933
 934         mutex_lock(&inode->i_mutex);
 935
 936         isize = i_size_read(inode);
 937
 938         blkoff = start >> blkbits;
 939         end_blkoff = (start + len - 1) >> blkbits;
 940
 941         delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
 942                                                         &delalloc_blkoff);
 943
 944         do {
 945                 __u64 blkphy;
 946                 unsigned int maxblocks;
 947
 948                 if (delalloc_blklen && blkoff == delalloc_blkoff) {
 949                         if (size) {
 950                                 /* End of the current extent */
 951                                 ret = fiemap_fill_next_extent(
 952                                         fieinfo, logical, phys, size, flags);
 953                                 if (ret)
 954                                         break;
 955                         }
 956                         if (blkoff > end_blkoff)
 957                                 break;
 958
 959                         flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
 960                         logical = blkoff << blkbits;
 961                         phys = 0;
 962                         size = delalloc_blklen << blkbits;
 963
 964                         blkoff = delalloc_blkoff + delalloc_blklen;
 965                         delalloc_blklen = nilfs_find_uncommitted_extent(
 966                                 inode, blkoff, &delalloc_blkoff);
 967                         continue;
 968                 }
 969
 970                 /*
 971                  * Limit the number of blocks that we look up so as
 972                  * not to get into the next delayed allocation extent.
 973                  */
 974                 maxblocks = INT_MAX;
 975                 if (delalloc_blklen)
 976                         maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
 977                                           maxblocks);
 978                 blkphy = 0;
 979
 980                 down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 981                 n = nilfs_bmap_lookup_contig(
 982                         NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
 983                 up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 984
 985                 if (n < 0) {
 986                         int past_eof;
 987
 988                         if (unlikely(n != -ENOENT))
 989                                 break; /* error */
 990
 991                         /* HOLE */
 992                         blkoff++;
 993                         past_eof = ((blkoff << blkbits) >= isize);
 994
 995                         if (size) {
 996                                 /* End of the current extent */
 997
 998                                 if (past_eof)
 999                                         flags |= FIEMAP_EXTENT_LAST;
1000
1001                                 ret = fiemap_fill_next_extent(
1002                                         fieinfo, logical, phys, size, flags);
1003                                 if (ret)
1004                                         break;
1005                                 size = 0;
1006                         }
1007                         if (blkoff > end_blkoff || past_eof)
1008                                 break;
1009                 } else {
1010                         if (size) {
1011                                 if (phys && blkphy << blkbits == phys + size) {
1012                                         /* The current extent goes on */
1013                                         size += n << blkbits;
1014                                 } else {
1015                                         /* Terminate the current extent */
1016                                         ret = fiemap_fill_next_extent(
1017                                                 fieinfo, logical, phys, size,
1018                                                 flags);
1019                                         if (ret || blkoff > end_blkoff)
1020                                                 break;
1021
1022                                         /* Start another extent */
1023                                         flags = FIEMAP_EXTENT_MERGED;
1024                                         logical = blkoff << blkbits;
1025                                         phys = blkphy << blkbits;
1026                                         size = n << blkbits;
1027                                 }
1028                         } else {
1029                                 /* Start a new extent */
1030                                 flags = FIEMAP_EXTENT_MERGED;
1031                                 logical = blkoff << blkbits;
1032                                 phys = blkphy << blkbits;
1033                                 size = n << blkbits;
1034                         }
1035                         blkoff += n;
1036                 }
1037                 cond_resched();
1038         } while (true);
1039
1040         /* If ret is 1 then we just hit the end of the extent array */
1041         if (ret == 1)
1042                 ret = 0;
1043
1044         mutex_unlock(&inode->i_mutex);
1045         return ret;
1046 }