fs/nilfs2/inode.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * inode.c - NILFS inode operations.
   4  *
   5  * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
   6  *
   7  * Written by Ryusuke Konishi.
   8  *
   9  */
  10
  11 #include <linux/buffer_head.h>
  12 #include <linux/gfp.h>
  13 #include <linux/mpage.h>
  14 #include <linux/pagemap.h>
  15 #include <linux/writeback.h>
  16 #include <linux/uio.h>
  17 #include "nilfs.h"
  18 #include "btnode.h"
  19 #include "segment.h"
  20 #include "page.h"
  21 #include "mdt.h"
  22 #include "cpfile.h"
  23 #include "ifile.h"
  24
  25 /**
  26  * struct nilfs_iget_args - arguments used during comparison between inodes
  27  * @ino: inode number
  28  * @cno: checkpoint number
  29  * @root: pointer on NILFS root object (mounted checkpoint)
  30  * @for_gc: inode for GC flag
  31  */
  32 struct nilfs_iget_args {
  33         u64 ino;
  34         __u64 cno;
  35         struct nilfs_root *root;
  36         int for_gc;
  37 };
  38
  39 static int nilfs_iget_test(struct inode *inode, void *opaque);
  40
  41 void nilfs_inode_add_blocks(struct inode *inode, int n)
  42 {
  43         struct nilfs_root *root = NILFS_I(inode)->i_root;
  44
  45         inode_add_bytes(inode, i_blocksize(inode) * n);
  46         if (root)
  47                 atomic64_add(n, &root->blocks_count);
  48 }
  49
  50 void nilfs_inode_sub_blocks(struct inode *inode, int n)
  51 {
  52         struct nilfs_root *root = NILFS_I(inode)->i_root;
  53
  54         inode_sub_bytes(inode, i_blocksize(inode) * n);
  55         if (root)
  56                 atomic64_sub(n, &root->blocks_count);
  57 }
  58
  59 /**
  60  * nilfs_get_block() - get a file block on the filesystem (callback function)
  61  * @inode - inode struct of the target file
  62  * @blkoff - file block number
  63  * @bh_result - buffer head to be mapped on
  64  * @create - indicate whether allocating the block or not when it has not
  65  *      been allocated yet.
  66  *
  67  * This function does not issue actual read request of the specified data
  68  * block. It is done by VFS.
  69  */
  70 int nilfs_get_block(struct inode *inode, sector_t blkoff,
  71                     struct buffer_head *bh_result, int create)
  72 {
  73         struct nilfs_inode_info *ii = NILFS_I(inode);
  74         struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
  75         __u64 blknum = 0;
  76         int err = 0, ret;
  77         unsigned int maxblocks = bh_result->b_size >> inode->i_blkbits;
  78
  79         down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  80         ret = nilfs_bmap_lookup_contig(ii->i_bmap, blkoff, &blknum, maxblocks);
  81         up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
  82         if (ret >= 0) { /* found */
  83                 map_bh(bh_result, inode->i_sb, blknum);
  84                 if (ret > 0)
  85                         bh_result->b_size = (ret << inode->i_blkbits);
  86                 goto out;
  87         }
  88         /* data block was not found */
  89         if (ret == -ENOENT && create) {
  90                 struct nilfs_transaction_info ti;
  91
  92                 bh_result->b_blocknr = 0;
  93                 err = nilfs_transaction_begin(inode->i_sb, &ti, 1);
  94                 if (unlikely(err))
  95                         goto out;
  96                 err = nilfs_bmap_insert(ii->i_bmap, blkoff,
  97                                         (unsigned long)bh_result);
  98                 if (unlikely(err != 0)) {
  99                         if (err == -EEXIST) {
 100                                 /*
 101                                  * The get_block() function could be called
 102                                  * from multiple callers for an inode.
 103                                  * However, the page having this block must
 104                                  * be locked in this case.
 105                                  */
 106                                 nilfs_msg(inode->i_sb, KERN_WARNING,
 107                                           "%s (ino=%lu): a race condition while inserting a data block at offset=%llu",
 108                                           __func__, inode->i_ino,
 109                                           (unsigned long long)blkoff);
 110                                 err = 0;
 111                         }
 112                         nilfs_transaction_abort(inode->i_sb);
 113                         goto out;
 114                 }
 115                 nilfs_mark_inode_dirty_sync(inode);
 116                 nilfs_transaction_commit(inode->i_sb); /* never fails */
 117                 /* Error handling should be detailed */
 118                 set_buffer_new(bh_result);
 119                 set_buffer_delay(bh_result);
 120                 map_bh(bh_result, inode->i_sb, 0);
 121                 /* Disk block number must be changed to proper value */
 122
 123         } else if (ret == -ENOENT) {
 124                 /*
 125                  * not found is not error (e.g. hole); must return without
 126                  * the mapped state flag.
 127                  */
 128                 ;
 129         } else {
 130                 err = ret;
 131         }
 132
 133  out:
 134         return err;
 135 }
 136
 137 /**
 138  * nilfs_readpage() - implement readpage() method of nilfs_aops {}
 139  * address_space_operations.
 140  * @file - file struct of the file to be read
 141  * @page - the page to be read
 142  */
 143 static int nilfs_readpage(struct file *file, struct page *page)
 144 {
 145         return mpage_readpage(page, nilfs_get_block);
 146 }
 147
 148 /**
 149  * nilfs_readpages() - implement readpages() method of nilfs_aops {}
 150  * address_space_operations.
 151  * @file - file struct of the file to be read
 152  * @mapping - address_space struct used for reading multiple pages
 153  * @pages - the pages to be read
 154  * @nr_pages - number of pages to be read
 155  */
 156 static int nilfs_readpages(struct file *file, struct address_space *mapping,
 157                            struct list_head *pages, unsigned int nr_pages)
 158 {
 159         return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
 160 }
 161
 162 static int nilfs_writepages(struct address_space *mapping,
 163                             struct writeback_control *wbc)
 164 {
 165         struct inode *inode = mapping->host;
 166         int err = 0;
 167
 168         if (sb_rdonly(inode->i_sb)) {
 169                 nilfs_clear_dirty_pages(mapping, false);
 170                 return -EROFS;
 171         }
 172
 173         if (wbc->sync_mode == WB_SYNC_ALL)
 174                 err = nilfs_construct_dsync_segment(inode->i_sb, inode,
 175                                                     wbc->range_start,
 176                                                     wbc->range_end);
 177         return err;
 178 }
 179
 180 static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
 181 {
 182         struct inode *inode = page->mapping->host;
 183         int err;
 184
 185         if (sb_rdonly(inode->i_sb)) {
 186                 /*
 187                  * It means that filesystem was remounted in read-only
 188                  * mode because of error or metadata corruption. But we
 189                  * have dirty pages that try to be flushed in background.
 190                  * So, here we simply discard this dirty page.
 191                  */
 192                 nilfs_clear_dirty_page(page, false);
 193                 unlock_page(page);
 194                 return -EROFS;
 195         }
 196
 197         redirty_page_for_writepage(wbc, page);
 198         unlock_page(page);
 199
 200         if (wbc->sync_mode == WB_SYNC_ALL) {
 201                 err = nilfs_construct_segment(inode->i_sb);
 202                 if (unlikely(err))
 203                         return err;
 204         } else if (wbc->for_reclaim)
 205                 nilfs_flush_segment(inode->i_sb, inode->i_ino);
 206
 207         return 0;
 208 }
 209
 210 static int nilfs_set_page_dirty(struct page *page)
 211 {
 212         struct inode *inode = page->mapping->host;
 213         int ret = __set_page_dirty_nobuffers(page);
 214
 215         if (page_has_buffers(page)) {
 216                 unsigned int nr_dirty = 0;
 217                 struct buffer_head *bh, *head;
 218
 219                 /*
 220                  * This page is locked by callers, and no other thread
 221                  * concurrently marks its buffers dirty since they are
 222                  * only dirtied through routines in fs/buffer.c in
 223                  * which call sites of mark_buffer_dirty are protected
 224                  * by page lock.
 225                  */
 226                 bh = head = page_buffers(page);
 227                 do {
 228                         /* Do not mark hole blocks dirty */
 229                         if (buffer_dirty(bh) || !buffer_mapped(bh))
 230                                 continue;
 231
 232                         set_buffer_dirty(bh);
 233                         nr_dirty++;
 234                 } while (bh = bh->b_this_page, bh != head);
 235
 236                 if (nr_dirty)
 237                         nilfs_set_file_dirty(inode, nr_dirty);
 238         } else if (ret) {
 239                 unsigned int nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
 240
 241                 nilfs_set_file_dirty(inode, nr_dirty);
 242         }
 243         return ret;
 244 }
 245
 246 void nilfs_write_failed(struct address_space *mapping, loff_t to)
 247 {
 248         struct inode *inode = mapping->host;
 249
 250         if (to > inode->i_size) {
 251                 truncate_pagecache(inode, inode->i_size);
 252                 nilfs_truncate(inode);
 253         }
 254 }
 255
 256 static int nilfs_write_begin(struct file *file, struct address_space *mapping,
 257                              loff_t pos, unsigned len, unsigned flags,
 258                              struct page **pagep, void **fsdata)
 259
 260 {
 261         struct inode *inode = mapping->host;
 262         int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
 263
 264         if (unlikely(err))
 265                 return err;
 266
 267         err = block_write_begin(mapping, pos, len, flags, pagep,
 268                                 nilfs_get_block);
 269         if (unlikely(err)) {
 270                 nilfs_write_failed(mapping, pos + len);
 271                 nilfs_transaction_abort(inode->i_sb);
 272         }
 273         return err;
 274 }
 275
 276 static int nilfs_write_end(struct file *file, struct address_space *mapping,
 277                            loff_t pos, unsigned len, unsigned copied,
 278                            struct page *page, void *fsdata)
 279 {
 280         struct inode *inode = mapping->host;
 281         unsigned int start = pos & (PAGE_SIZE - 1);
 282         unsigned int nr_dirty;
 283         int err;
 284
 285         nr_dirty = nilfs_page_count_clean_buffers(page, start,
 286                                                   start + copied);
 287         copied = generic_write_end(file, mapping, pos, len, copied, page,
 288                                    fsdata);
 289         nilfs_set_file_dirty(inode, nr_dirty);
 290         err = nilfs_transaction_commit(inode->i_sb);
 291         return err ? : copied;
 292 }
 293
 294 static ssize_t
 295 nilfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 296 {
 297         struct inode *inode = file_inode(iocb->ki_filp);
 298
 299         if (iov_iter_rw(iter) == WRITE)
 300                 return 0;
 301
 302         /* Needs synchronization with the cleaner */
 303         return blockdev_direct_IO(iocb, inode, iter, nilfs_get_block);
 304 }
 305
 306 const struct address_space_operations nilfs_aops = {
 307         .writepage              = nilfs_writepage,
 308         .readpage               = nilfs_readpage,
 309         .writepages             = nilfs_writepages,
 310         .set_page_dirty         = nilfs_set_page_dirty,
 311         .readpages              = nilfs_readpages,
 312         .write_begin            = nilfs_write_begin,
 313         .write_end              = nilfs_write_end,
 314         /* .releasepage         = nilfs_releasepage, */
 315         .invalidatepage         = block_invalidatepage,
 316         .direct_IO              = nilfs_direct_IO,
 317         .is_partially_uptodate  = block_is_partially_uptodate,
 318 };
 319
 320 static int nilfs_insert_inode_locked(struct inode *inode,
 321                                      struct nilfs_root *root,
 322                                      unsigned long ino)
 323 {
 324         struct nilfs_iget_args args = {
 325                 .ino = ino, .root = root, .cno = 0, .for_gc = 0
 326         };
 327
 328         return insert_inode_locked4(inode, ino, nilfs_iget_test, &args);
 329 }
 330
 331 struct inode *nilfs_new_inode(struct inode *dir, umode_t mode)
 332 {
 333         struct super_block *sb = dir->i_sb;
 334         struct the_nilfs *nilfs = sb->s_fs_info;
 335         struct inode *inode;
 336         struct nilfs_inode_info *ii;
 337         struct nilfs_root *root;
 338         int err = -ENOMEM;
 339         ino_t ino;
 340
 341         inode = new_inode(sb);
 342         if (unlikely(!inode))
 343                 goto failed;
 344
 345         mapping_set_gfp_mask(inode->i_mapping,
 346                            mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 347
 348         root = NILFS_I(dir)->i_root;
 349         ii = NILFS_I(inode);
 350         ii->i_state = BIT(NILFS_I_NEW);
 351         ii->i_root = root;
 352
 353         err = nilfs_ifile_create_inode(root->ifile, &ino, &ii->i_bh);
 354         if (unlikely(err))
 355                 goto failed_ifile_create_inode;
 356         /* reference count of i_bh inherits from nilfs_mdt_read_block() */
 357
 358         atomic64_inc(&root->inodes_count);
 359         inode_init_owner(inode, dir, mode);
 360         inode->i_ino = ino;
 361         inode->i_mtime = inode->i_atime = inode->i_ctime = current_time(inode);
 362
 363         if (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode)) {
 364                 err = nilfs_bmap_read(ii->i_bmap, NULL);
 365                 if (err < 0)
 366                         goto failed_after_creation;
 367
 368                 set_bit(NILFS_I_BMAP, &ii->i_state);
 369                 /* No lock is needed; iget() ensures it. */
 370         }
 371
 372         ii->i_flags = nilfs_mask_flags(
 373                 mode, NILFS_I(dir)->i_flags & NILFS_FL_INHERITED);
 374
 375         /* ii->i_file_acl = 0; */
 376         /* ii->i_dir_acl = 0; */
 377         ii->i_dir_start_lookup = 0;
 378         nilfs_set_inode_flags(inode);
 379         spin_lock(&nilfs->ns_next_gen_lock);
 380         inode->i_generation = nilfs->ns_next_generation++;
 381         spin_unlock(&nilfs->ns_next_gen_lock);
 382         if (nilfs_insert_inode_locked(inode, root, ino) < 0) {
 383                 err = -EIO;
 384                 goto failed_after_creation;
 385         }
 386
 387         err = nilfs_init_acl(inode, dir);
 388         if (unlikely(err))
 389                 /*
 390                  * Never occur.  When supporting nilfs_init_acl(),
 391                  * proper cancellation of above jobs should be considered.
 392                  */
 393                 goto failed_after_creation;
 394
 395         return inode;
 396
 397  failed_after_creation:
 398         clear_nlink(inode);
 399         unlock_new_inode(inode);
 400         iput(inode);  /*
 401                        * raw_inode will be deleted through
 402                        * nilfs_evict_inode().
 403                        */
 404         goto failed;
 405
 406  failed_ifile_create_inode:
 407         make_bad_inode(inode);
 408         iput(inode);
 409  failed:
 410         return ERR_PTR(err);
 411 }
 412
 413 void nilfs_set_inode_flags(struct inode *inode)
 414 {
 415         unsigned int flags = NILFS_I(inode)->i_flags;
 416         unsigned int new_fl = 0;
 417
 418         if (flags & FS_SYNC_FL)
 419                 new_fl |= S_SYNC;
 420         if (flags & FS_APPEND_FL)
 421                 new_fl |= S_APPEND;
 422         if (flags & FS_IMMUTABLE_FL)
 423                 new_fl |= S_IMMUTABLE;
 424         if (flags & FS_NOATIME_FL)
 425                 new_fl |= S_NOATIME;
 426         if (flags & FS_DIRSYNC_FL)
 427                 new_fl |= S_DIRSYNC;
 428         inode_set_flags(inode, new_fl, S_SYNC | S_APPEND | S_IMMUTABLE |
 429                         S_NOATIME | S_DIRSYNC);
 430 }
 431
 432 int nilfs_read_inode_common(struct inode *inode,
 433                             struct nilfs_inode *raw_inode)
 434 {
 435         struct nilfs_inode_info *ii = NILFS_I(inode);
 436         int err;
 437
 438         inode->i_mode = le16_to_cpu(raw_inode->i_mode);
 439         i_uid_write(inode, le32_to_cpu(raw_inode->i_uid));
 440         i_gid_write(inode, le32_to_cpu(raw_inode->i_gid));
 441         set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
 442         inode->i_size = le64_to_cpu(raw_inode->i_size);
 443         inode->i_atime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 444         inode->i_ctime.tv_sec = le64_to_cpu(raw_inode->i_ctime);
 445         inode->i_mtime.tv_sec = le64_to_cpu(raw_inode->i_mtime);
 446         inode->i_atime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 447         inode->i_ctime.tv_nsec = le32_to_cpu(raw_inode->i_ctime_nsec);
 448         inode->i_mtime.tv_nsec = le32_to_cpu(raw_inode->i_mtime_nsec);
 449         if (inode->i_nlink == 0)
 450                 return -ESTALE; /* this inode is deleted */
 451
 452         inode->i_blocks = le64_to_cpu(raw_inode->i_blocks);
 453         ii->i_flags = le32_to_cpu(raw_inode->i_flags);
 454 #if 0
 455         ii->i_file_acl = le32_to_cpu(raw_inode->i_file_acl);
 456         ii->i_dir_acl = S_ISREG(inode->i_mode) ?
 457                 0 : le32_to_cpu(raw_inode->i_dir_acl);
 458 #endif
 459         ii->i_dir_start_lookup = 0;
 460         inode->i_generation = le32_to_cpu(raw_inode->i_generation);
 461
 462         if (S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
 463             S_ISLNK(inode->i_mode)) {
 464                 err = nilfs_bmap_read(ii->i_bmap, raw_inode);
 465                 if (err < 0)
 466                         return err;
 467                 set_bit(NILFS_I_BMAP, &ii->i_state);
 468                 /* No lock is needed; iget() ensures it. */
 469         }
 470         return 0;
 471 }
 472
 473 static int __nilfs_read_inode(struct super_block *sb,
 474                               struct nilfs_root *root, unsigned long ino,
 475                               struct inode *inode)
 476 {
 477         struct the_nilfs *nilfs = sb->s_fs_info;
 478         struct buffer_head *bh;
 479         struct nilfs_inode *raw_inode;
 480         int err;
 481
 482         down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 483         err = nilfs_ifile_get_inode_block(root->ifile, ino, &bh);
 484         if (unlikely(err))
 485                 goto bad_inode;
 486
 487         raw_inode = nilfs_ifile_map_inode(root->ifile, ino, bh);
 488
 489         err = nilfs_read_inode_common(inode, raw_inode);
 490         if (err)
 491                 goto failed_unmap;
 492
 493         if (S_ISREG(inode->i_mode)) {
 494                 inode->i_op = &nilfs_file_inode_operations;
 495                 inode->i_fop = &nilfs_file_operations;
 496                 inode->i_mapping->a_ops = &nilfs_aops;
 497         } else if (S_ISDIR(inode->i_mode)) {
 498                 inode->i_op = &nilfs_dir_inode_operations;
 499                 inode->i_fop = &nilfs_dir_operations;
 500                 inode->i_mapping->a_ops = &nilfs_aops;
 501         } else if (S_ISLNK(inode->i_mode)) {
 502                 inode->i_op = &nilfs_symlink_inode_operations;
 503                 inode_nohighmem(inode);
 504                 inode->i_mapping->a_ops = &nilfs_aops;
 505         } else {
 506                 inode->i_op = &nilfs_special_inode_operations;
 507                 init_special_inode(
 508                         inode, inode->i_mode,
 509                         huge_decode_dev(le64_to_cpu(raw_inode->i_device_code)));
 510         }
 511         nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 512         brelse(bh);
 513         up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 514         nilfs_set_inode_flags(inode);
 515         mapping_set_gfp_mask(inode->i_mapping,
 516                            mapping_gfp_constraint(inode->i_mapping, ~__GFP_FS));
 517         return 0;
 518
 519  failed_unmap:
 520         nilfs_ifile_unmap_inode(root->ifile, ino, bh);
 521         brelse(bh);
 522
 523  bad_inode:
 524         up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 525         return err;
 526 }
 527
 528 static int nilfs_iget_test(struct inode *inode, void *opaque)
 529 {
 530         struct nilfs_iget_args *args = opaque;
 531         struct nilfs_inode_info *ii;
 532
 533         if (args->ino != inode->i_ino || args->root != NILFS_I(inode)->i_root)
 534                 return 0;
 535
 536         ii = NILFS_I(inode);
 537         if (!test_bit(NILFS_I_GCINODE, &ii->i_state))
 538                 return !args->for_gc;
 539
 540         return args->for_gc && args->cno == ii->i_cno;
 541 }
 542
 543 static int nilfs_iget_set(struct inode *inode, void *opaque)
 544 {
 545         struct nilfs_iget_args *args = opaque;
 546
 547         inode->i_ino = args->ino;
 548         if (args->for_gc) {
 549                 NILFS_I(inode)->i_state = BIT(NILFS_I_GCINODE);
 550                 NILFS_I(inode)->i_cno = args->cno;
 551                 NILFS_I(inode)->i_root = NULL;
 552         } else {
 553                 if (args->root && args->ino == NILFS_ROOT_INO)
 554                         nilfs_get_root(args->root);
 555                 NILFS_I(inode)->i_root = args->root;
 556         }
 557         return 0;
 558 }
 559
 560 struct inode *nilfs_ilookup(struct super_block *sb, struct nilfs_root *root,
 561                             unsigned long ino)
 562 {
 563         struct nilfs_iget_args args = {
 564                 .ino = ino, .root = root, .cno = 0, .for_gc = 0
 565         };
 566
 567         return ilookup5(sb, ino, nilfs_iget_test, &args);
 568 }
 569
 570 struct inode *nilfs_iget_locked(struct super_block *sb, struct nilfs_root *root,
 571                                 unsigned long ino)
 572 {
 573         struct nilfs_iget_args args = {
 574                 .ino = ino, .root = root, .cno = 0, .for_gc = 0
 575         };
 576
 577         return iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 578 }
 579
 580 struct inode *nilfs_iget(struct super_block *sb, struct nilfs_root *root,
 581                          unsigned long ino)
 582 {
 583         struct inode *inode;
 584         int err;
 585
 586         inode = nilfs_iget_locked(sb, root, ino);
 587         if (unlikely(!inode))
 588                 return ERR_PTR(-ENOMEM);
 589         if (!(inode->i_state & I_NEW))
 590                 return inode;
 591
 592         err = __nilfs_read_inode(sb, root, ino, inode);
 593         if (unlikely(err)) {
 594                 iget_failed(inode);
 595                 return ERR_PTR(err);
 596         }
 597         unlock_new_inode(inode);
 598         return inode;
 599 }
 600
 601 struct inode *nilfs_iget_for_gc(struct super_block *sb, unsigned long ino,
 602                                 __u64 cno)
 603 {
 604         struct nilfs_iget_args args = {
 605                 .ino = ino, .root = NULL, .cno = cno, .for_gc = 1
 606         };
 607         struct inode *inode;
 608         int err;
 609
 610         inode = iget5_locked(sb, ino, nilfs_iget_test, nilfs_iget_set, &args);
 611         if (unlikely(!inode))
 612                 return ERR_PTR(-ENOMEM);
 613         if (!(inode->i_state & I_NEW))
 614                 return inode;
 615
 616         err = nilfs_init_gcinode(inode);
 617         if (unlikely(err)) {
 618                 iget_failed(inode);
 619                 return ERR_PTR(err);
 620         }
 621         unlock_new_inode(inode);
 622         return inode;
 623 }
 624
 625 void nilfs_write_inode_common(struct inode *inode,
 626                               struct nilfs_inode *raw_inode, int has_bmap)
 627 {
 628         struct nilfs_inode_info *ii = NILFS_I(inode);
 629
 630         raw_inode->i_mode = cpu_to_le16(inode->i_mode);
 631         raw_inode->i_uid = cpu_to_le32(i_uid_read(inode));
 632         raw_inode->i_gid = cpu_to_le32(i_gid_read(inode));
 633         raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
 634         raw_inode->i_size = cpu_to_le64(inode->i_size);
 635         raw_inode->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec);
 636         raw_inode->i_mtime = cpu_to_le64(inode->i_mtime.tv_sec);
 637         raw_inode->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 638         raw_inode->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
 639         raw_inode->i_blocks = cpu_to_le64(inode->i_blocks);
 640
 641         raw_inode->i_flags = cpu_to_le32(ii->i_flags);
 642         raw_inode->i_generation = cpu_to_le32(inode->i_generation);
 643
 644         if (NILFS_ROOT_METADATA_FILE(inode->i_ino)) {
 645                 struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 646
 647                 /* zero-fill unused portion in the case of super root block */
 648                 raw_inode->i_xattr = 0;
 649                 raw_inode->i_pad = 0;
 650                 memset((void *)raw_inode + sizeof(*raw_inode), 0,
 651                        nilfs->ns_inode_size - sizeof(*raw_inode));
 652         }
 653
 654         if (has_bmap)
 655                 nilfs_bmap_write(ii->i_bmap, raw_inode);
 656         else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
 657                 raw_inode->i_device_code =
 658                         cpu_to_le64(huge_encode_dev(inode->i_rdev));
 659         /*
 660          * When extending inode, nilfs->ns_inode_size should be checked
 661          * for substitutions of appended fields.
 662          */
 663 }
 664
 665 void nilfs_update_inode(struct inode *inode, struct buffer_head *ibh, int flags)
 666 {
 667         ino_t ino = inode->i_ino;
 668         struct nilfs_inode_info *ii = NILFS_I(inode);
 669         struct inode *ifile = ii->i_root->ifile;
 670         struct nilfs_inode *raw_inode;
 671
 672         raw_inode = nilfs_ifile_map_inode(ifile, ino, ibh);
 673
 674         if (test_and_clear_bit(NILFS_I_NEW, &ii->i_state))
 675                 memset(raw_inode, 0, NILFS_MDT(ifile)->mi_entry_size);
 676         if (flags & I_DIRTY_DATASYNC)
 677                 set_bit(NILFS_I_INODE_SYNC, &ii->i_state);
 678
 679         nilfs_write_inode_common(inode, raw_inode, 0);
 680                 /*
 681                  * XXX: call with has_bmap = 0 is a workaround to avoid
 682                  * deadlock of bmap.  This delays update of i_bmap to just
 683                  * before writing.
 684                  */
 685
 686         nilfs_ifile_unmap_inode(ifile, ino, ibh);
 687 }
 688
 689 #define NILFS_MAX_TRUNCATE_BLOCKS       16384  /* 64MB for 4KB block */
 690
 691 static void nilfs_truncate_bmap(struct nilfs_inode_info *ii,
 692                                 unsigned long from)
 693 {
 694         __u64 b;
 695         int ret;
 696
 697         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 698                 return;
 699 repeat:
 700         ret = nilfs_bmap_last_key(ii->i_bmap, &b);
 701         if (ret == -ENOENT)
 702                 return;
 703         else if (ret < 0)
 704                 goto failed;
 705
 706         if (b < from)
 707                 return;
 708
 709         b -= min_t(__u64, NILFS_MAX_TRUNCATE_BLOCKS, b - from);
 710         ret = nilfs_bmap_truncate(ii->i_bmap, b);
 711         nilfs_relax_pressure_in_lock(ii->vfs_inode.i_sb);
 712         if (!ret || (ret == -ENOMEM &&
 713                      nilfs_bmap_truncate(ii->i_bmap, b) == 0))
 714                 goto repeat;
 715
 716 failed:
 717         nilfs_msg(ii->vfs_inode.i_sb, KERN_WARNING,
 718                   "error %d truncating bmap (ino=%lu)", ret,
 719                   ii->vfs_inode.i_ino);
 720 }
 721
 722 void nilfs_truncate(struct inode *inode)
 723 {
 724         unsigned long blkoff;
 725         unsigned int blocksize;
 726         struct nilfs_transaction_info ti;
 727         struct super_block *sb = inode->i_sb;
 728         struct nilfs_inode_info *ii = NILFS_I(inode);
 729
 730         if (!test_bit(NILFS_I_BMAP, &ii->i_state))
 731                 return;
 732         if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
 733                 return;
 734
 735         blocksize = sb->s_blocksize;
 736         blkoff = (inode->i_size + blocksize - 1) >> sb->s_blocksize_bits;
 737         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 738
 739         block_truncate_page(inode->i_mapping, inode->i_size, nilfs_get_block);
 740
 741         nilfs_truncate_bmap(ii, blkoff);
 742
 743         inode->i_mtime = inode->i_ctime = current_time(inode);
 744         if (IS_SYNC(inode))
 745                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
 746
 747         nilfs_mark_inode_dirty(inode);
 748         nilfs_set_file_dirty(inode, 0);
 749         nilfs_transaction_commit(sb);
 750         /*
 751          * May construct a logical segment and may fail in sync mode.
 752          * But truncate has no return value.
 753          */
 754 }
 755
 756 static void nilfs_clear_inode(struct inode *inode)
 757 {
 758         struct nilfs_inode_info *ii = NILFS_I(inode);
 759
 760         /*
 761          * Free resources allocated in nilfs_read_inode(), here.
 762          */
 763         BUG_ON(!list_empty(&ii->i_dirty));
 764         brelse(ii->i_bh);
 765         ii->i_bh = NULL;
 766
 767         if (nilfs_is_metadata_file_inode(inode))
 768                 nilfs_mdt_clear(inode);
 769
 770         if (test_bit(NILFS_I_BMAP, &ii->i_state))
 771                 nilfs_bmap_clear(ii->i_bmap);
 772
 773         nilfs_btnode_cache_clear(&ii->i_btnode_cache);
 774
 775         if (ii->i_root && inode->i_ino == NILFS_ROOT_INO)
 776                 nilfs_put_root(ii->i_root);
 777 }
 778
 779 void nilfs_evict_inode(struct inode *inode)
 780 {
 781         struct nilfs_transaction_info ti;
 782         struct super_block *sb = inode->i_sb;
 783         struct nilfs_inode_info *ii = NILFS_I(inode);
 784         int ret;
 785
 786         if (inode->i_nlink || !ii->i_root || unlikely(is_bad_inode(inode))) {
 787                 truncate_inode_pages_final(&inode->i_data);
 788                 clear_inode(inode);
 789                 nilfs_clear_inode(inode);
 790                 return;
 791         }
 792         nilfs_transaction_begin(sb, &ti, 0); /* never fails */
 793
 794         truncate_inode_pages_final(&inode->i_data);
 795
 796         /* TODO: some of the following operations may fail.  */
 797         nilfs_truncate_bmap(ii, 0);
 798         nilfs_mark_inode_dirty(inode);
 799         clear_inode(inode);
 800
 801         ret = nilfs_ifile_delete_inode(ii->i_root->ifile, inode->i_ino);
 802         if (!ret)
 803                 atomic64_dec(&ii->i_root->inodes_count);
 804
 805         nilfs_clear_inode(inode);
 806
 807         if (IS_SYNC(inode))
 808                 nilfs_set_transaction_flag(NILFS_TI_SYNC);
 809         nilfs_transaction_commit(sb);
 810         /*
 811          * May construct a logical segment and may fail in sync mode.
 812          * But delete_inode has no return value.
 813          */
 814 }
 815
 816 int nilfs_setattr(struct dentry *dentry, struct iattr *iattr)
 817 {
 818         struct nilfs_transaction_info ti;
 819         struct inode *inode = d_inode(dentry);
 820         struct super_block *sb = inode->i_sb;
 821         int err;
 822
 823         err = setattr_prepare(dentry, iattr);
 824         if (err)
 825                 return err;
 826
 827         err = nilfs_transaction_begin(sb, &ti, 0);
 828         if (unlikely(err))
 829                 return err;
 830
 831         if ((iattr->ia_valid & ATTR_SIZE) &&
 832             iattr->ia_size != i_size_read(inode)) {
 833                 inode_dio_wait(inode);
 834                 truncate_setsize(inode, iattr->ia_size);
 835                 nilfs_truncate(inode);
 836         }
 837
 838         setattr_copy(inode, iattr);
 839         mark_inode_dirty(inode);
 840
 841         if (iattr->ia_valid & ATTR_MODE) {
 842                 err = nilfs_acl_chmod(inode);
 843                 if (unlikely(err))
 844                         goto out_err;
 845         }
 846
 847         return nilfs_transaction_commit(sb);
 848
 849 out_err:
 850         nilfs_transaction_abort(sb);
 851         return err;
 852 }
 853
 854 int nilfs_permission(struct inode *inode, int mask)
 855 {
 856         struct nilfs_root *root = NILFS_I(inode)->i_root;
 857
 858         if ((mask & MAY_WRITE) && root &&
 859             root->cno != NILFS_CPTREE_CURRENT_CNO)
 860                 return -EROFS; /* snapshot is not writable */
 861
 862         return generic_permission(inode, mask);
 863 }
 864
 865 int nilfs_load_inode_block(struct inode *inode, struct buffer_head **pbh)
 866 {
 867         struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 868         struct nilfs_inode_info *ii = NILFS_I(inode);
 869         int err;
 870
 871         spin_lock(&nilfs->ns_inode_lock);
 872         if (ii->i_bh == NULL) {
 873                 spin_unlock(&nilfs->ns_inode_lock);
 874                 err = nilfs_ifile_get_inode_block(ii->i_root->ifile,
 875                                                   inode->i_ino, pbh);
 876                 if (unlikely(err))
 877                         return err;
 878                 spin_lock(&nilfs->ns_inode_lock);
 879                 if (ii->i_bh == NULL)
 880                         ii->i_bh = *pbh;
 881                 else {
 882                         brelse(*pbh);
 883                         *pbh = ii->i_bh;
 884                 }
 885         } else
 886                 *pbh = ii->i_bh;
 887
 888         get_bh(*pbh);
 889         spin_unlock(&nilfs->ns_inode_lock);
 890         return 0;
 891 }
 892
 893 int nilfs_inode_dirty(struct inode *inode)
 894 {
 895         struct nilfs_inode_info *ii = NILFS_I(inode);
 896         struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 897         int ret = 0;
 898
 899         if (!list_empty(&ii->i_dirty)) {
 900                 spin_lock(&nilfs->ns_inode_lock);
 901                 ret = test_bit(NILFS_I_DIRTY, &ii->i_state) ||
 902                         test_bit(NILFS_I_BUSY, &ii->i_state);
 903                 spin_unlock(&nilfs->ns_inode_lock);
 904         }
 905         return ret;
 906 }
 907
 908 int nilfs_set_file_dirty(struct inode *inode, unsigned int nr_dirty)
 909 {
 910         struct nilfs_inode_info *ii = NILFS_I(inode);
 911         struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 912
 913         atomic_add(nr_dirty, &nilfs->ns_ndirtyblks);
 914
 915         if (test_and_set_bit(NILFS_I_DIRTY, &ii->i_state))
 916                 return 0;
 917
 918         spin_lock(&nilfs->ns_inode_lock);
 919         if (!test_bit(NILFS_I_QUEUED, &ii->i_state) &&
 920             !test_bit(NILFS_I_BUSY, &ii->i_state)) {
 921                 /*
 922                  * Because this routine may race with nilfs_dispose_list(),
 923                  * we have to check NILFS_I_QUEUED here, too.
 924                  */
 925                 if (list_empty(&ii->i_dirty) && igrab(inode) == NULL) {
 926                         /*
 927                          * This will happen when somebody is freeing
 928                          * this inode.
 929                          */
 930                         nilfs_msg(inode->i_sb, KERN_WARNING,
 931                                   "cannot set file dirty (ino=%lu): the file is being freed",
 932                                   inode->i_ino);
 933                         spin_unlock(&nilfs->ns_inode_lock);
 934                         return -EINVAL; /*
 935                                          * NILFS_I_DIRTY may remain for
 936                                          * freeing inode.
 937                                          */
 938                 }
 939                 list_move_tail(&ii->i_dirty, &nilfs->ns_dirty_files);
 940                 set_bit(NILFS_I_QUEUED, &ii->i_state);
 941         }
 942         spin_unlock(&nilfs->ns_inode_lock);
 943         return 0;
 944 }
 945
 946 int __nilfs_mark_inode_dirty(struct inode *inode, int flags)
 947 {
 948         struct buffer_head *ibh;
 949         int err;
 950
 951         err = nilfs_load_inode_block(inode, &ibh);
 952         if (unlikely(err)) {
 953                 nilfs_msg(inode->i_sb, KERN_WARNING,
 954                           "cannot mark inode dirty (ino=%lu): error %d loading inode block",
 955                           inode->i_ino, err);
 956                 return err;
 957         }
 958         nilfs_update_inode(inode, ibh, flags);
 959         mark_buffer_dirty(ibh);
 960         nilfs_mdt_mark_dirty(NILFS_I(inode)->i_root->ifile);
 961         brelse(ibh);
 962         return 0;
 963 }
 964
 965 /**
 966  * nilfs_dirty_inode - reflect changes on given inode to an inode block.
 967  * @inode: inode of the file to be registered.
 968  *
 969  * nilfs_dirty_inode() loads a inode block containing the specified
 970  * @inode and copies data from a nilfs_inode to a corresponding inode
 971  * entry in the inode block. This operation is excluded from the segment
 972  * construction. This function can be called both as a single operation
 973  * and as a part of indivisible file operations.
 974  */
 975 void nilfs_dirty_inode(struct inode *inode, int flags)
 976 {
 977         struct nilfs_transaction_info ti;
 978         struct nilfs_mdt_info *mdi = NILFS_MDT(inode);
 979
 980         if (is_bad_inode(inode)) {
 981                 nilfs_msg(inode->i_sb, KERN_WARNING,
 982                           "tried to mark bad_inode dirty. ignored.");
 983                 dump_stack();
 984                 return;
 985         }
 986         if (mdi) {
 987                 nilfs_mdt_mark_dirty(inode);
 988                 return;
 989         }
 990         nilfs_transaction_begin(inode->i_sb, &ti, 0);
 991         __nilfs_mark_inode_dirty(inode, flags);
 992         nilfs_transaction_commit(inode->i_sb); /* never fails */
 993 }
 994
 995 int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 996                  __u64 start, __u64 len)
 997 {
 998         struct the_nilfs *nilfs = inode->i_sb->s_fs_info;
 999         __u64 logical = 0, phys = 0, size = 0;
1000         __u32 flags = 0;
1001         loff_t isize;
1002         sector_t blkoff, end_blkoff;
1003         sector_t delalloc_blkoff;
1004         unsigned long delalloc_blklen;
1005         unsigned int blkbits = inode->i_blkbits;
1006         int ret, n;
1007
1008         ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1009         if (ret)
1010                 return ret;
1011
1012         inode_lock(inode);
1013
1014         isize = i_size_read(inode);
1015
1016         blkoff = start >> blkbits;
1017         end_blkoff = (start + len - 1) >> blkbits;
1018
1019         delalloc_blklen = nilfs_find_uncommitted_extent(inode, blkoff,
1020                                                         &delalloc_blkoff);
1021
1022         do {
1023                 __u64 blkphy;
1024                 unsigned int maxblocks;
1025
1026                 if (delalloc_blklen && blkoff == delalloc_blkoff) {
1027                         if (size) {
1028                                 /* End of the current extent */
1029                                 ret = fiemap_fill_next_extent(
1030                                         fieinfo, logical, phys, size, flags);
1031                                 if (ret)
1032                                         break;
1033                         }
1034                         if (blkoff > end_blkoff)
1035                                 break;
1036
1037                         flags = FIEMAP_EXTENT_MERGED | FIEMAP_EXTENT_DELALLOC;
1038                         logical = blkoff << blkbits;
1039                         phys = 0;
1040                         size = delalloc_blklen << blkbits;
1041
1042                         blkoff = delalloc_blkoff + delalloc_blklen;
1043                         delalloc_blklen = nilfs_find_uncommitted_extent(
1044                                 inode, blkoff, &delalloc_blkoff);
1045                         continue;
1046                 }
1047
1048                 /*
1049                  * Limit the number of blocks that we look up so as
1050                  * not to get into the next delayed allocation extent.
1051                  */
1052                 maxblocks = INT_MAX;
1053                 if (delalloc_blklen)
1054                         maxblocks = min_t(sector_t, delalloc_blkoff - blkoff,
1055                                           maxblocks);
1056                 blkphy = 0;
1057
1058                 down_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1059                 n = nilfs_bmap_lookup_contig(
1060                         NILFS_I(inode)->i_bmap, blkoff, &blkphy, maxblocks);
1061                 up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
1062
1063                 if (n < 0) {
1064                         int past_eof;
1065
1066                         if (unlikely(n != -ENOENT))
1067                                 break; /* error */
1068
1069                         /* HOLE */
1070                         blkoff++;
1071                         past_eof = ((blkoff << blkbits) >= isize);
1072
1073                         if (size) {
1074                                 /* End of the current extent */
1075
1076                                 if (past_eof)
1077                                         flags |= FIEMAP_EXTENT_LAST;
1078
1079                                 ret = fiemap_fill_next_extent(
1080                                         fieinfo, logical, phys, size, flags);
1081                                 if (ret)
1082                                         break;
1083                                 size = 0;
1084                         }
1085                         if (blkoff > end_blkoff || past_eof)
1086                                 break;
1087                 } else {
1088                         if (size) {
1089                                 if (phys && blkphy << blkbits == phys + size) {
1090                                         /* The current extent goes on */
1091                                         size += n << blkbits;
1092                                 } else {
1093                                         /* Terminate the current extent */
1094                                         ret = fiemap_fill_next_extent(
1095                                                 fieinfo, logical, phys, size,
1096                                                 flags);
1097                                         if (ret || blkoff > end_blkoff)
1098                                                 break;
1099
1100                                         /* Start another extent */
1101                                         flags = FIEMAP_EXTENT_MERGED;
1102                                         logical = blkoff << blkbits;
1103                                         phys = blkphy << blkbits;
1104                                         size = n << blkbits;
1105                                 }
1106                         } else {
1107                                 /* Start a new extent */
1108                                 flags = FIEMAP_EXTENT_MERGED;
1109                                 logical = blkoff << blkbits;
1110                                 phys = blkphy << blkbits;
1111                                 size = n << blkbits;
1112                         }
1113                         blkoff += n;
1114                 }
1115                 cond_resched();
1116         } while (true);
1117
1118         /* If ret is 1 then we just hit the end of the extent array */
1119         if (ret == 1)
1120                 ret = 0;
1121
1122         inode_unlock(inode);
1123         return ret;
1124 }