| blob | 68415cb4f23cab39861119c68838b1b099029df2 |
1 /*
2 * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it would be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write the Free Software Foundation,
16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18 #include <linux/log2.h>
54 /*
55 * Used in xfs_itruncate(). This is the maximum number of extents
56 * freed from a file in a single transaction.
57 */
58 #define XFS_ITRUNC_MAX_EXTENTS 2
65 #ifdef DEBUG
66 /*
67 * Make sure that the extents in the given memory buffer
68 * are valid.
69 */
70 STATIC void
74 xfs_exntfmt_t fmt)
75 {
76 xfs_bmbt_irec_t irec;
77 xfs_bmbt_rec_host_t rec;
87 }
88 }
90 #define xfs_validate_extents(ifp, nrecs, fmt)
93 /*
94 * Check that none of the inode's in the buffer have a next
95 * unlinked field of 0.
96 */
97 #if defined(DEBUG)
98 void
102 {
114 "Detected a bogus zero next_unlinked field in incore inode buffer 0x%p. About to pop an ASSERT.",
115 bp);
117 }
118 }
119 }
120 #endif
122 /*
123 * Find the buffer associated with the given inode map
124 * We do basic validation checks on the buffer once it has been
125 * retrieved from disk.
126 */
127 STATIC int
133 uint buf_flags,
134 uint iget_flags)
135 {
146 "xfs_imap_to_bp: xfs_trans_read_buf()returned "
151 }
153 }
155 /*
156 * Validate the magic number and version of every inode in the buffer
157 * (if DEBUG kernel) or the first inode in the buffer, otherwise.
158 */
159 #ifdef DEBUG
163 #endif
174 XFS_ERRTAG_ITOBP_INOTOBP,
175 XFS_RANDOM_ITOBP_INOTOBP))) {
179 }
182 #ifdef DEBUG
184 "Device %s - bad inode magic/vsn "
189 #endif
192 }
193 }
197 /*
198 * Mark the buffer as an inode buffer now that it looks good
199 */
204 }
206 /*
207 * This routine is called to map an inode number within a file
208 * system to the buffer containing the on-disk version of the
209 * inode. It returns a pointer to the buffer containing the
210 * on-disk inode in the bpp parameter, and in the dip parameter
211 * it returns a pointer to the on-disk inode within that buffer.
212 *
213 * If a non-zero error is returned, then the contents of bpp and
214 * dipp are undefined.
215 *
216 * Use xfs_imap() to determine the size and location of the
217 * buffer to read from disk.
218 */
219 int
223 xfs_ino_t ino,
227 uint imap_flags)
228 {
246 }
249 /*
250 * This routine is called to map an inode to the buffer containing
251 * the on-disk version of the inode. It returns a pointer to the
252 * buffer containing the on-disk inode in the bpp parameter, and in
253 * the dip parameter it returns a pointer to the on-disk inode within
254 * that buffer.
255 *
256 * If a non-zero error is returned, then the contents of bpp and
257 * dipp are undefined.
258 *
259 * The inode is expected to already been mapped to its buffer and read
260 * in once, thus we can use the mapping information stored in the inode
261 * rather than calling xfs_imap(). This allows us to avoid the overhead
262 * of looking at the inode btree for small block file systems
263 * (see xfs_imap()).
264 */
265 int
272 uint buf_flags)
273 {
288 }
293 }
295 /*
296 * Move inode type and inode format specific information from the
297 * on-disk inode to the in-core inode. For fifos, devs, and sockets
298 * this means set if_rdev to the proper value. For files, directories,
299 * and symlinks this means to bring in the in-line data or extent
300 * pointers. For a file in B-tree format, only the root is immediately
301 * brought in-core. The rest will be in-lined in if_extents when it
302 * is first referenced (see xfs_iread_extents()).
303 */
304 STATIC int
308 {
312 xfs_fsize_t di_size;
330 }
340 }
350 }
361 }
372 /*
373 * no local regular files yet
374 */
377 "corrupt inode %Lu "
381 XFS_ERRLEVEL_LOW,
384 }
389 "corrupt inode %Lu "
394 XFS_ERRLEVEL_LOW,
397 }
412 }
418 }
421 }
435 "corrupt inode %Lu "
440 XFS_ERRLEVEL_LOW,
443 }
456 }
461 }
463 }
465 /*
466 * The file is in-lined in the on-disk inode.
467 * If it fits into if_inline_data, then copy
468 * it there, otherwise allocate a buffer for it
469 * and copy the data there. Either way, set
470 * if_data to point at the data.
471 * If we allocate a buffer for the data, make
472 * sure that its size is a multiple of 4 and
473 * record the real size in i_real_bytes.
474 */
475 STATIC int
481 {
485 /*
486 * If the size is unreasonable, then something
487 * is wrong and we just bail out rather than crash in
488 * kmem_alloc() or memcpy() below.
489 */
492 "corrupt inode %Lu "
499 }
509 }
517 }
519 /*
520 * The file consists of a set of extents all
521 * of which fit into the on-disk inode.
522 * If there are few enough extents to fit into
523 * the if_inline_ext, then copy them there.
524 * Otherwise allocate a buffer for them and copy
525 * them into it. Either way, set if_extents
526 * to point at the extents.
527 */
528 STATIC int
533 {
544 /*
545 * If the number of extents is unreasonable, then something
546 * is wrong and we just bail out rather than crash in
547 * kmem_alloc() or memcpy() below.
548 */
556 }
563 else
574 }
581 XFS_ERRLEVEL_LOW,
584 }
585 }
588 }
590 /*
591 * The file has too many extents to fit into
592 * the inode, so they are in B-tree format.
593 * Allocate a buffer for the root of the B-tree
594 * and copy the root into it. The i_extents
595 * field will remain NULL until all of the
596 * extents are read in (when they are needed).
597 */
598 STATIC int
603 {
606 /* REFERENCED */
615 /*
616 * blow out if -- fork has less extents than can fit in
617 * fork (fork shouldn't be a btree format), root btree
618 * block has more records than can fit into the fork,
619 * or the number of extents is greater than the number of
620 * blocks.
621 */
632 }
637 /*
638 * Copy and convert from the on-disk structure
639 * to the in-memory structure.
640 */
648 }
650 STATIC void
654 {
683 }
685 void
689 {
718 }
720 STATIC uint
722 __uint16_t di_flags)
723 {
755 }
758 }
760 uint
763 {
768 }
770 uint
773 {
776 }
778 /*
779 * Read the disk inode attributes into the in-core inode structure.
780 */
781 int
786 uint iget_flags)
787 {
792 /*
793 * Fill in the location information in the in-core inode.
794 */
799 /*
800 * Get pointers to the on-disk inode and the buffer containing it.
801 */
808 /*
809 * If we got something that isn't an inode it means someone
810 * (nfs or dmi) has a stale handle.
811 */
813 #ifdef DEBUG
815 "dip->di_magic (0x%x) != "
818 XFS_DINODE_MAGIC);
822 }
824 /*
825 * If the on-disk inode is already linked to a directory
826 * entry, copy all of the inode into the in-core inode.
827 * xfs_iformat() handles copying in the inode format
828 * specific information.
829 * Otherwise, just get the truly permanent information.
830 */
835 #ifdef DEBUG
838 error);
841 }
847 /*
848 * Make sure to pull in the mode here as well in
849 * case the inode is released without being used.
850 * This ensures that xfs_inactive() will see that
851 * the inode is already free and not try to mess
852 * with the uninitialized part of it.
853 */
855 /*
856 * Initialize the per-fork minima and maxima for a new
857 * inode here. xfs_iformat will do it for old inodes.
858 */
861 }
863 /*
864 * The inode format changed when we moved the link count and
865 * made it 32 bits long. If this is an old format inode,
866 * convert it in memory to look like a new one. If it gets
867 * flushed to disk we will convert back before flushing or
868 * logging it. We zero out the new projid field and the old link
869 * count field. We'll handle clearing the pad field (the remains
870 * of the old uuid field) when we actually convert the inode to
871 * the new format. We don't change the version number so that we
872 * can distinguish this from a real new format inode.
873 */
878 }
883 /*
884 * Mark the buffer containing the inode as something to keep
885 * around for a while. This helps to keep recently accessed
886 * meta-data in-core longer.
887 */
890 /*
891 * Use xfs_trans_brelse() to release the buffer containing the
892 * on-disk inode, because it was acquired with xfs_trans_read_buf()
893 * in xfs_itobp() above. If tp is NULL, this is just a normal
894 * brelse(). If we're within a transaction, then xfs_trans_brelse()
895 * will only release the buffer if it is not dirty within the
896 * transaction. It will be OK to release the buffer in this case,
897 * because inodes on disk are never destroyed and we will be
898 * locking the new in-core inode before putting it in the hash
899 * table where other processes can find it. Thus we don't have
900 * to worry about the inode being changed just because we released
901 * the buffer.
902 */
903 out_brelse:
906 }
908 /*
909 * Read in extents from a btree-format inode.
910 * Allocate and fill in if_extents. Real work is done in xfs_bmap.c.
911 */
912 int
917 {
920 xfs_extnum_t nextents;
926 }
930 /*
931 * We know that the size is valid (it's checked in iformat_btree)
932 */
942 }
945 }
947 /*
948 * Allocate an inode on disk and return a copy of its in-core version.
949 * The in-core inode is locked exclusively. Set mode, nlink, and rdev
950 * appropriately within the inode. The uid and gid for the inode are
951 * set according to the contents of the given cred structure.
952 *
953 * Use xfs_dialloc() to allocate the on-disk inode. If xfs_dialloc()
954 * has a free inode available, call xfs_iget()
955 * to obtain the in-core version of the allocated inode. Finally,
956 * fill in the inode and log its initial contents. In this case,
957 * ialloc_context would be set to NULL and call_again set to false.
958 *
959 * If xfs_dialloc() does not have an available inode,
960 * it will replenish its supply by doing an allocation. Since we can
961 * only do one allocation within a transaction without deadlocks, we
962 * must commit the current transaction before returning the inode itself.
963 * In this case, therefore, we will set call_again to true and return.
964 * The caller should then commit the current transaction, start a new
965 * transaction, and call xfs_ialloc() again to actually get the inode.
966 *
967 * To ensure that some other process does not grab the inode that
968 * was allocated during the first call to xfs_ialloc(), this routine
969 * also returns the [locked] bp pointing to the head of the freelist
970 * as ialloc_context. The caller should hold this buffer across
971 * the commit and pass it back into this routine on the second call.
972 *
973 * If we are allocating quota inodes, we do not have a parent inode
974 * to attach to or associate with (i.e. pip == NULL) because they
975 * are not linked into the directory structure - they are attached
976 * directly to the superblock - and so have no parent.
977 */
978 int
982 mode_t mode,
983 xfs_nlink_t nlink,
984 xfs_dev_t rdev,
986 xfs_prid_t prid,
991 {
992 xfs_ino_t ino;
994 uint flags;
996 timespec_t tv;
999 /*
1000 * Call the space management code to pick
1001 * the on-disk inode to be allocated.
1002 */
1010 }
1013 /*
1014 * Get the in-core inode with the lock held exclusively.
1015 * This is because we're setting fields here we need
1016 * to prevent others from looking at until we're done.
1017 */
1033 /*
1034 * If the superblock version is up to where we support new format
1035 * inodes and this is currently an old format inode, then change
1036 * the inode version number now. This way we only do the conversion
1037 * here rather than here and in the flush/logging code.
1038 */
1042 /*
1043 * We've already zeroed the old link count, the projid field,
1044 * and the pad field.
1045 */
1046 }
1048 /*
1049 * Project ids won't be stored on disk if we are using a version 1 inode.
1050 */
1058 }
1059 }
1061 /*
1062 * If the group ID of the new file does not match the effective group
1063 * ID or one of the supplementary group IDs, the S_ISGID bit is cleared
1064 * (and only if the irix_sgid_inherit compatibility variable is set).
1065 */
1070 }
1083 /*
1084 * di_gen will have been taken care of in xfs_iread.
1085 */
1102 /*
1103 * we can't set up filestreams until after the VFS inode
1104 * is set up properly.
1105 */
1108 /* fall through */
1119 }
1126 }
1127 }
1129 xfs_inherit_noatime)
1132 xfs_inherit_nodump)
1135 xfs_inherit_sync)
1138 xfs_inherit_nosymlinks)
1143 xfs_inherit_nodefrag)
1148 }
1149 /* FALLTHROUGH */
1158 }
1159 /*
1160 * Attribute fork settings for new inode.
1161 */
1165 /*
1166 * Log the new values stuffed into the inode.
1167 */
1170 /* now that we have an i_mode we can setup inode ops and unlock */
1173 /* now we have set up the vfs inode we can associate the filestream */
1180 }
1184 }
1186 /*
1187 * Check to make sure that there are no blocks allocated to the
1188 * file beyond the size of the file. We don't check this for
1189 * files with fixed size extents or real time extents, but we
1190 * at least do it for regular files.
1191 */
1192 #ifdef DEBUG
1193 void
1197 xfs_fsize_t isize)
1198 {
1199 xfs_fileoff_t map_first;
1214 /*
1215 * The filesystem could be shutting down, so bmapi may return
1216 * an error.
1217 */
1221 map_first),
1223 NULL))
1227 }
1230 /*
1231 * Calculate the last possible buffered byte in a file. This must
1232 * include data that was buffered beyond the EOF by the write code.
1233 * This also needs to deal with overflowing the xfs_fsize_t type
1234 * which can happen for sizes near the limit.
1235 *
1236 * We also need to take into account any blocks beyond the EOF. It
1237 * may be the case that they were buffered by a write which failed.
1238 * In that case the pages will still be in memory, but the inode size
1239 * will never have been updated.
1240 */
1241 STATIC xfs_fsize_t
1244 {
1246 xfs_fsize_t last_byte;
1247 xfs_fileoff_t last_block;
1248 xfs_fileoff_t size_last_block;
1254 /*
1255 * Only check for blocks beyond the EOF if the extents have
1256 * been read in. This eliminates the need for the inode lock,
1257 * and it also saves us from looking when it really isn't
1258 * necessary.
1259 */
1263 XFS_DATA_FORK);
1267 }
1270 }
1277 }
1281 }
1283 }
1285 /*
1286 * Start the truncation of the file to new_size. The new size
1287 * must be smaller than the current size. This routine will
1288 * clear the buffer and page caches of file data in the removed
1289 * range, and xfs_itruncate_finish() will remove the underlying
1290 * disk blocks.
1291 *
1292 * The inode must have its I/O lock locked EXCLUSIVELY, and it
1293 * must NOT have the inode lock held at all. This is because we're
1294 * calling into the buffer/page cache code and we can't hold the
1295 * inode lock when we do so.
1296 *
1297 * We need to wait for any direct I/Os in flight to complete before we
1298 * proceed with the truncate. This is needed to prevent the extents
1299 * being read or written by the direct I/Os from being removed while the
1300 * I/O is in flight as there is no other method of synchronising
1301 * direct I/O with the truncate operation. Also, because we hold
1302 * the IOLOCK in exclusive mode, we prevent new direct I/Os from being
1303 * started until the truncate completes and drops the lock. Essentially,
1304 * the xfs_ioend_wait() call forms an I/O barrier that provides strict
1305 * ordering between direct I/Os and the truncate operation.
1306 *
1307 * The flags parameter can have either the value XFS_ITRUNC_DEFINITE
1308 * or XFS_ITRUNC_MAYBE. The XFS_ITRUNC_MAYBE value should be used
1309 * in the case that the caller is locking things out of order and
1310 * may not be able to call xfs_itruncate_finish() with the inode lock
1311 * held without dropping the I/O lock. If the caller must drop the
1312 * I/O lock before calling xfs_itruncate_finish(), then xfs_itruncate_start()
1313 * must be called again with all the same restrictions as the initial
1314 * call.
1315 */
1316 int
1319 uint flags,
1320 xfs_fsize_t new_size)
1321 {
1322 xfs_fsize_t last_byte;
1323 xfs_off_t toss_start;
1334 /* wait for the completion of any pending DIOs */
1338 /*
1339 * Call toss_pages or flushinval_pages to get rid of pages
1340 * overlapping the region being removed. We have to use
1341 * the less efficient flushinval_pages in the case that the
1342 * caller may not be able to finish the truncate without
1343 * dropping the inode's I/O lock. Make sure
1344 * to catch any pages brought in by buffers overlapping
1345 * the EOF by searching out beyond the isize by our
1346 * block size. We round new_size up to a block boundary
1347 * so that we don't toss things on the same block as
1348 * new_size but before it.
1349 *
1350 * Before calling toss_page or flushinval_pages, make sure to
1351 * call remapf() over the same region if the file is mapped.
1352 * This frees up mapped file references to the pages in the
1353 * given range and for the flushinval_pages case it ensures
1354 * that we get the latest mapped changes flushed out.
1355 */
1359 /*
1360 * The place to start tossing is beyond our maximum
1361 * file size, so there is no way that the data extended
1362 * out there.
1363 */
1365 }
1375 }
1376 }
1378 #ifdef DEBUG
1381 }
1382 #endif
1384 }
1386 /*
1387 * Shrink the file to the given new_size. The new size must be smaller than
1388 * the current size. This will free up the underlying blocks in the removed
1389 * range after a call to xfs_itruncate_start() or xfs_atruncate_start().
1390 *
1391 * The transaction passed to this routine must have made a permanent log
1392 * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the
1393 * given transaction and start new ones, so make sure everything involved in
1394 * the transaction is tidy before calling here. Some transaction will be
1395 * returned to the caller to be committed. The incoming transaction must
1396 * already include the inode, and both inode locks must be held exclusively.
1397 * The inode must also be "held" within the transaction. On return the inode
1398 * will be "held" within the returned transaction. This routine does NOT
1399 * require any disk space to be reserved for it within the transaction.
1400 *
1401 * The fork parameter must be either xfs_attr_fork or xfs_data_fork, and it
1402 * indicates the fork which is to be truncated. For the attribute fork we only
1403 * support truncation to size 0.
1404 *
1405 * We use the sync parameter to indicate whether or not the first transaction
1406 * we perform might have to be synchronous. For the attr fork, it needs to be
1407 * so if the unlink of the inode is not yet known to be permanent in the log.
1408 * This keeps us from freeing and reusing the blocks of the attribute fork
1409 * before the unlink of the inode becomes permanent.
1410 *
1411 * For the data fork, we normally have to run synchronously if we're being
1412 * called out of the inactive path or we're being called out of the create path
1413 * where we're truncating an existing file. Either way, the truncate needs to
1414 * be sync so blocks don't reappear in the file with altered data in case of a
1415 * crash. wsync filesystems can run the first case async because anything that
1416 * shrinks the inode has to run sync so by the time we're called here from
1417 * inactive, the inode size is permanently set to 0.
1418 *
1419 * Calls from the truncate path always need to be sync unless we're in a wsync
1420 * filesystem and the file has already been unlinked.
1421 *
1422 * The caller is responsible for correctly setting the sync parameter. It gets
1423 * too hard for us to guess here which path we're being called out of just
1424 * based on inode state.
1425 *
1426 * If we get an error, we must return with the inode locked and linked into the
1427 * current transaction. This keeps things simple for the higher level code,
1428 * because it always knows that the inode is locked and held in the transaction
1429 * that returns to it whether errors occur or not. We don't mark the inode
1430 * dirty on error so that transactions can be easily aborted if possible.
1431 */
1432 int
1436 xfs_fsize_t new_size,
1439 {
1440 xfs_fsblock_t first_block;
1441 xfs_fileoff_t first_unmap_block;
1442 xfs_fileoff_t last_block;
1448 xfs_bmap_free_t free_list;
1464 /*
1465 * We only support truncating the entire attribute fork.
1466 */
1469 }
1473 /*
1474 * The first thing we do is set the size to new_size permanently
1475 * on disk. This way we don't have to worry about anyone ever
1476 * being able to look at the data being freed even in the face
1477 * of a crash. What we're getting around here is the case where
1478 * we free a block, it is allocated to another file, it is written
1479 * to, and then we crash. If the new data gets written to the
1480 * file but the log buffers containing the free and reallocation
1481 * don't, then we'd end up with garbage in the blocks being freed.
1482 * As long as we make the new_size permanent before actually
1483 * freeing any blocks it doesn't matter if they get writtten to.
1484 *
1485 * The callers must signal into us whether or not the size
1486 * setting here must be synchronous. There are a few cases
1487 * where it doesn't have to be synchronous. Those cases
1488 * occur if the file is unlinked and we know the unlink is
1489 * permanent or if the blocks being truncated are guaranteed
1490 * to be beyond the inode eof (regardless of the link count)
1491 * and the eof value is permanent. Both of these cases occur
1492 * only on wsync-mounted filesystems. In those cases, we're
1493 * guaranteed that no user will ever see the data in the blocks
1494 * that are being truncated so the truncate can run async.
1495 * In the free beyond eof case, the file may wind up with
1496 * more blocks allocated to it than it needs if we crash
1497 * and that won't get fixed until the next time the file
1498 * is re-opened and closed but that's ok as that shouldn't
1499 * be too many blocks.
1500 *
1501 * However, we can't just make all wsync xactions run async
1502 * because there's one call out of the create path that needs
1503 * to run sync where it's truncating an existing file to size
1504 * 0 whose size is > 0.
1505 *
1506 * It's probably possible to come up with a test in this
1507 * routine that would correctly distinguish all the above
1508 * cases from the values of the function parameters and the
1509 * inode state but for sanity's sake, I've decided to let the
1510 * layers above just tell us. It's simpler to correctly figure
1511 * out in the layer above exactly under what conditions we
1512 * can run async and I think it's easier for others read and
1513 * follow the logic in case something has to be changed.
1514 * cscope is your friend -- rcc.
1515 *
1516 * The attribute fork is much simpler.
1517 *
1518 * For the attribute fork we allow the caller to tell us whether
1519 * the unlink of the inode that led to this call is yet permanent
1520 * in the on disk log. If it is not and we will be freeing extents
1521 * in this inode then we make the first transaction synchronous
1522 * to make sure that the unlink is permanent by the time we free
1523 * the blocks.
1524 */
1527 /*
1528 * If we are not changing the file size then do
1529 * not update the on-disk file size - we may be
1530 * called from xfs_inactive_free_eofblocks(). If we
1531 * update the on-disk file size and then the system
1532 * crashes before the contents of the file are
1533 * flushed to disk then the files may be full of
1534 * holes (ie NULL files bug).
1535 */
1540 }
1541 }
1546 }
1552 /*
1553 * Since it is possible for space to become allocated beyond
1554 * the end of the file (in a crash where the space is allocated
1555 * but the inode size is not yet updated), simply remove any
1556 * blocks which show up between the new EOF and the maximum
1557 * possible file size. If the first block to be removed is
1558 * beyond the maximum file size (ie it is the same as last_block),
1559 * then there is nothing to do.
1560 */
1568 }
1570 /*
1571 * Free up up to XFS_ITRUNC_MAX_EXTENTS. xfs_bunmapi()
1572 * will tell us whether it freed the entire range or
1573 * not. If this is a synchronous mount (wsync),
1574 * then we can tell bunmapi to keep all the
1575 * transactions asynchronous since the unlink
1576 * transaction that made this inode inactive has
1577 * already hit the disk. There's no danger of
1578 * the freed blocks being reused, there being a
1579 * crash, and the reused blocks suddenly reappearing
1580 * in this file with garbage in them once recovery
1581 * runs.
1582 */
1587 XFS_ITRUNC_MAX_EXTENTS,
1591 /*
1592 * If the bunmapi call encounters an error,
1593 * return to the caller where the transaction
1594 * can be properly aborted. We just need to
1595 * make sure we're not holding any resources
1596 * that we were not when we came in.
1597 */
1600 }
1602 /*
1603 * Duplicate the transaction that has the permanent
1604 * reservation and commit the old transaction.
1605 */
1612 /*
1613 * If the bmap finish call encounters an error, return
1614 * to the caller where the transaction can be properly
1615 * aborted. We just need to make sure we're not
1616 * holding any resources that we were not when we came
1617 * in.
1618 *
1619 * Aborting from this point might lose some blocks in
1620 * the file system, but oh well.
1621 */
1624 }
1627 /*
1628 * Mark the inode dirty so it will be logged and
1629 * moved forward in the log as part of every commit.
1630 */
1632 }
1642 /*
1643 * transaction commit worked ok so we can drop the extra ticket
1644 * reference that we gained in xfs_trans_dup()
1645 */
1649 XFS_TRANS_PERM_LOG_RES,
1650 XFS_ITRUNCATE_LOG_COUNT);
1653 }
1654 /*
1655 * Only update the size in the case of the data fork, but
1656 * always re-log the inode so that our permanent transaction
1657 * can keep on rolling it forward in the log.
1658 */
1661 /*
1662 * If we are not changing the file size then do
1663 * not update the on-disk file size - we may be
1664 * called from xfs_inactive_free_eofblocks(). If we
1665 * update the on-disk file size and then the system
1666 * crashes before the contents of the file are
1667 * flushed to disk then the files may be full of
1668 * holes (ie NULL files bug).
1669 */
1673 }
1674 }
1684 }
1686 /*
1687 * This is called when the inode's link count goes to 0.
1688 * We place the on-disk inode on a list in the AGI. It
1689 * will be pulled from this list when the inode is freed.
1690 */
1691 int
1695 {
1701 xfs_agino_t agino;
1712 /*
1713 * Get the agi buffer first. It ensures lock ordering
1714 * on the list.
1715 */
1721 /*
1722 * Get the index into the agi hash table for the
1723 * list this inode will go on.
1724 */
1732 /*
1733 * There is already another inode in the bucket we need
1734 * to add ourselves to. Add us at the front of the list.
1735 * Here we put the head pointer into our next pointer,
1736 * and then we fall through to point the head at us.
1737 */
1743 /* both on-disk, don't endian flip twice */
1751 }
1753 /*
1754 * Point the bucket head pointer at the inode being inserted.
1755 */
1763 }
1765 /*
1766 * Pull the on-disk inode from the AGI unlinked list.
1767 */
1768 STATIC int
1772 {
1773 xfs_ino_t next_ino;
1779 xfs_agnumber_t agno;
1780 xfs_agino_t agino;
1781 xfs_agino_t next_agino;
1791 /*
1792 * Get the agi buffer first. It ensures lock ordering
1793 * on the list.
1794 */
1801 /*
1802 * Get the index into the agi hash table for the
1803 * list this inode will go on.
1804 */
1812 /*
1813 * We're at the head of the list. Get the inode's
1814 * on-disk buffer to see if there is anyone after us
1815 * on the list. Only modify our next pointer if it
1816 * is not already NULLAGINO. This saves us the overhead
1817 * of dealing with the buffer when there is no need to
1818 * change it.
1819 */
1826 }
1839 }
1840 /*
1841 * Point the bucket head pointer at the next inode.
1842 */
1851 /*
1852 * We need to search the list for the inode being freed.
1853 */
1857 /*
1858 * If the last inode wasn't the one pointing to
1859 * us, then release its buffer since we're not
1860 * going to do anything with it.
1861 */
1864 }
1873 }
1877 }
1878 /*
1879 * Now last_ibp points to the buffer previous to us on
1880 * the unlinked list. Pull us from the list.
1881 */
1888 }
1902 }
1903 /*
1904 * Point the previous inode on the list to the next inode.
1905 */
1913 }
1915 }
1917 STATIC void
1921 xfs_ino_t inum)
1922 {
1928 xfs_daddr_t blkno;
1945 }
1953 /*
1954 * We obtain and lock the backing buffer first in the process
1955 * here, as we have to ensure that any dirty inode that we
1956 * can't get the flush lock on is attached to the buffer.
1957 * If we scan the in-memory inodes first, then buffer IO can
1958 * complete before we get a lock on it, and hence we may fail
1959 * to mark all the active inodes on the buffer stale.
1960 */
1963 XBF_LOCK);
1965 /*
1966 * Walk the inodes already attached to the buffer and mark them
1967 * stale. These will all have the flush locks held, so an
1968 * in-memory inode walk can't lock them.
1969 */
1980 found++;
1981 }
1983 }
1985 /*
1986 * For each inode in memory attempt to add it to the inode
1987 * buffer and set it up for being staled on buffer IO
1988 * completion. This is safe as we've locked out tail pushing
1989 * and flushing by locking the buffer.
1990 *
1991 * We have already marked every inode that was part of a
1992 * transaction stale above, which means there is no point in
1993 * even trying to lock them.
1994 */
2000 /* Inode not in memory or stale, nothing to do */
2004 }
2006 /* don't try to lock/unlock the current inode */
2011 }
2018 }
2026 }
2030 /* inode with unlogged changes only */
2036 }
2037 found++;
2050 }
2055 }
2058 }
2060 /*
2061 * This is called to return an inode to the inode free list.
2062 * The inode should already be truncated to 0 length and have
2063 * no pages associated with it. This routine also assumes that
2064 * the inode is already a part of the transaction.
2065 *
2066 * The on-disk copy of the inode will have been added to the list
2067 * of unlinked inodes in the AGI. We need to remove the inode from
2068 * that list atomically with respect to freeing it here.
2069 */
2070 int
2075 {
2078 xfs_ino_t first_ino;
2091 /*
2092 * Pull the on-disk inode from the AGI unlinked list.
2093 */
2097 }
2102 }
2111 /*
2112 * Bump the generation count so no one will be confused
2113 * by reincarnations of this inode.
2114 */
2123 /*
2124 * Clear the on-disk di_mode. This is to prevent xfs_bulkstat
2125 * from picking up this inode when it is reclaimed (its incore state
2126 * initialzed but not flushed to disk yet). The in-core di_mode is
2127 * already cleared and a corresponding transaction logged.
2128 * The hack here just synchronizes the in-core to on-disk
2129 * di_mode value in advance before the actual inode sync to disk.
2130 * This is OK because the inode is already unlinked and would never
2131 * change its di_mode again for this inode generation.
2132 * This is a temporary hack that would require a proper fix
2133 * in the future.
2134 */
2139 }
2142 }
2144 /*
2145 * Reallocate the space for if_broot based on the number of records
2146 * being added or deleted as indicated in rec_diff. Move the records
2147 * and pointers in if_broot to fit the new size. When shrinking this
2148 * will eliminate holes between the records and pointers created by
2149 * the caller. When growing this will create holes to be filled in
2150 * by the caller.
2151 *
2152 * The caller must not request to add more records than would fit in
2153 * the on-disk inode root. If the if_broot is currently NULL, then
2154 * if we adding records one will be allocated. The caller must also
2155 * not request that the number of records go below zero, although
2156 * it can go to zero.
2157 *
2158 * ip -- the inode whose if_broot area is changing
2159 * ext_diff -- the change in the number of records, positive or negative,
2160 * requested for the if_broot array.
2161 */
2162 void
2167 {
2177 /*
2178 * Handle the degenerate case quietly.
2179 */
2182 }
2186 /*
2187 * If there wasn't any memory allocated before, just
2188 * allocate it now and get out.
2189 */
2195 }
2197 /*
2198 * If there is already an existing if_broot, then we need
2199 * to realloc() it and shift the pointers to their new
2200 * location. The records don't change location because
2201 * they are kept butted up against the btree block header.
2202 */
2218 }
2220 /*
2221 * rec_diff is less than 0. In this case, we are shrinking the
2222 * if_broot buffer. It must already exist. If we go to zero
2223 * records, just get rid of the root and clear the status bit.
2224 */
2231 else
2235 /*
2236 * First copy over the btree block header.
2237 */
2242 }
2244 /*
2245 * Only copy the records and pointers if there are any.
2246 */
2248 /*
2249 * First copy the records.
2250 */
2255 /*
2256 * Then copy the pointers.
2257 */
2263 }
2270 }
2273 /*
2274 * This is called when the amount of space needed for if_data
2275 * is increased or decreased. The change in size is indicated by
2276 * the number of bytes that need to be added or deleted in the
2277 * byte_diff parameter.
2278 *
2279 * If the amount of space needed has decreased below the size of the
2280 * inline buffer, then switch to using the inline buffer. Otherwise,
2281 * use kmem_realloc() or kmem_alloc() to adjust the size of the buffer
2282 * to what is needed.
2283 *
2284 * ip -- the inode whose if_data area is changing
2285 * byte_diff -- the change in the number of bytes, positive or negative,
2286 * requested for the if_data array.
2287 */
2288 void
2293 {
2300 }
2309 }
2313 /*
2314 * If the valid extents/data can fit in if_inline_ext/data,
2315 * copy them from the malloc'd vector and free it.
2316 */
2322 new_size);
2325 }
2328 /*
2329 * Stuck with malloc/realloc.
2330 * For inline data, the underlying buffer must be
2331 * a multiple of 4 bytes in size so that it can be
2332 * logged and stay on word boundaries. We enforce
2333 * that here.
2334 */
2341 /*
2342 * Only do the realloc if the underlying size
2343 * is really changing.
2344 */
2348 real_size,
2351 }
2358 }
2359 }
2363 }
2365 void
2369 {
2376 }
2378 /*
2379 * If the format is local, then we can't have an extents
2380 * array so just look for an inline data array. If we're
2381 * not local then we may or may not have an extents list,
2382 * so check and free it up if we do.
2383 */
2391 }
2398 }
2405 }
2406 }
2408 /*
2409 * This is called to unpin an inode. The caller must have the inode locked
2410 * in at least shared mode so that the buffer cannot be subsequently pinned
2411 * once someone is waiting for it to be unpinned.
2412 */
2413 static void
2416 {
2421 /* Give the log a push to start the unpinning I/O */
2424 }
2426 void
2429 {
2433 }
2434 }
2436 /*
2437 * xfs_iextents_copy()
2438 *
2439 * This is called to copy the REAL extents (as opposed to the delayed
2440 * allocation extents) from the inode into the given buffer. It
2441 * returns the number of bytes copied into the buffer.
2442 *
2443 * If there are no delayed allocation extents, then we can just
2444 * memcpy() the extents into the buffer. Otherwise, we need to
2445 * examine each extent in turn and skip those which are delayed.
2446 */
2447 int
2452 {
2457 xfs_fsblock_t start_block;
2467 /*
2468 * There are some delayed allocation extents in the
2469 * inode, so copy the extents one at a time and skip
2470 * the delayed ones. There must be at least one
2471 * non-delayed extent.
2472 */
2478 /*
2479 * It's a delayed allocation extent, so skip it.
2480 */
2482 }
2484 /* Translate to on disk format */
2487 dp++;
2488 copied++;
2489 }
2494 }
2496 /*
2497 * Each of the following cases stores data into the same region
2498 * of the on-disk inode, so only one of them can be valid at
2499 * any given time. While it is possible to have conflicting formats
2500 * and log flags, e.g. having XFS_ILOG_?DATA set when the fork is
2501 * in EXTENTS format, this can only happen when the fork has
2502 * changed formats after being modified but before being flushed.
2503 * In these cases, the format always takes precedence, because the
2504 * format indicates the current state of the fork.
2505 */
2506 /*ARGSUSED*/
2507 STATIC void
2514 {
2518 #ifdef XFS_TRANS_DEBUG
2520 #endif
2531 /*
2532 * This can happen if we gave up in iformat in an error path,
2533 * for the attribute fork.
2534 */
2538 }
2548 }
2562 whichfork);
2563 }
2572 XFS_BROOT_SIZE_ADJ));
2576 }
2583 }
2592 }
2598 }
2599 }
2601 STATIC int
2605 {
2629 /* really need a gang lookup range call here */
2639 /* if the inode lies outside this cluster, we're done. */
2642 /*
2643 * Do an un-protected check to see if the inode is dirty and
2644 * is a candidate for flushing. These checks will be repeated
2645 * later after the appropriate locks are acquired.
2646 */
2650 /*
2651 * Try to get locks. If any are unavailable or it is pinned,
2652 * then this inode cannot be flushed and is skipped.
2653 */
2660 }
2665 }
2667 /*
2668 * arriving here means that this inode can be flushed. First
2669 * re-check that it's dirty before flushing.
2670 */
2677 }
2678 clcount++;
2681 }
2683 }
2688 }
2690 out_free:
2693 out_put:
2698 cluster_corrupt_out:
2699 /*
2700 * Corruption detected in the clustering loop. Invalidate the
2701 * inode buffer and shut down the filesystem.
2702 */
2704 /*
2705 * Clean up the buffer. If it was B_DELWRI, just release it --
2706 * brelse can handle it with no problems. If not, shut down the
2707 * filesystem before releasing the buffer.
2708 */
2716 /*
2717 * Just like incore_relse: if we have b_iodone functions,
2718 * mark the buffer as an error and call them. Otherwise
2719 * mark it as stale and brelse.
2720 */
2729 }
2730 }
2732 /*
2733 * Unlocks the flush lock
2734 */
2739 }
2741 /*
2742 * xfs_iflush() will write a modified inode's changes out to the
2743 * inode's on disk home. The caller must have the inode lock held
2744 * in at least shared mode and the inode flush completion must be
2745 * active as well. The inode lock will still be held upon return from
2746 * the call and the caller is free to unlock it.
2747 * The inode flush will be completed when the inode reaches the disk.
2748 * The flags indicate how the inode's buffer should be written out.
2749 */
2750 int
2753 uint flags)
2754 {
2771 /*
2772 * We can't flush the inode until it is unpinned, so wait for it if we
2773 * are allowed to block. We know noone new can pin it, because we are
2774 * holding the inode lock shared and you need to hold it exclusively to
2775 * pin the inode.
2776 *
2777 * If we are not allowed to block, force the log out asynchronously so
2778 * that when we come back the inode will be unpinned. If other inodes
2779 * in the same cluster are dirty, they will probably write the inode
2780 * out for us if they occur after the log force completes.
2781 */
2786 }
2789 /*
2790 * For stale inodes we cannot rely on the backing buffer remaining
2791 * stale in cache for the remaining life of the stale inode and so
2792 * xfs_itobp() below may give us a buffer that no longer contains
2793 * inodes below. We have to check this after ensuring the inode is
2794 * unpinned so that it is safe to reclaim the stale inode after the
2795 * flush call.
2796 */
2800 }
2802 /*
2803 * This may have been unpinned because the filesystem is shutting
2804 * down forcibly. If that's the case we must not write this inode
2805 * to disk, because the log record didn't make it to disk!
2806 */
2813 }
2815 /*
2816 * Get the buffer containing the on-disk inode.
2817 */
2823 }
2825 /*
2826 * First flush out the inode that xfs_iflush was called with.
2827 */
2832 /*
2833 * If the buffer is pinned then push on the log now so we won't
2834 * get stuck waiting in the write for too long.
2835 */
2839 /*
2840 * inode clustering:
2841 * see if other inodes can be gathered into this write
2842 */
2849 else
2853 corrupt_out:
2856 cluster_corrupt_out:
2857 /*
2858 * Unlocks the flush lock
2859 */
2862 }
2865 STATIC int
2869 {
2873 #ifdef XFS_TRANS_DEBUG
2875 #endif
2885 /* set *dip = inode's place in the buffer */
2888 /*
2889 * Clear i_update_core before copying out the data.
2890 * This is for coordination with our timestamp updates
2891 * that don't hold the inode lock. They will always
2892 * update the timestamps BEFORE setting i_update_core,
2893 * so if we clear i_update_core after they set it we
2894 * are guaranteed to see their updates to the timestamps.
2895 * I believe that this depends on strongly ordered memory
2896 * semantics, but we have that. We use the SYNCHRONIZE
2897 * macro to make sure that the compiler does not reorder
2898 * the i_update_core access below the data copy below.
2899 */
2903 /*
2904 * Make sure to get the latest timestamps from the Linux inode.
2905 */
2914 }
2921 }
2931 }
2942 }
2943 }
2946 XFS_RANDOM_IFLUSH_5)) {
2952 ip);
2954 }
2961 }
2962 /*
2963 * bump the flush iteration count, used to detect flushes which
2964 * postdate a log record during recovery.
2965 */
2969 /*
2970 * Copy the dirty parts of the inode into the on-disk
2971 * inode. We always copy out the core of the inode,
2972 * because if the inode is dirty at all the core must
2973 * be.
2974 */
2977 /* Wrap, we never let the log put out DI_MAX_FLUSH */
2981 /*
2982 * If this is really an old format inode and the superblock version
2983 * has not been updated to support only new format inodes, then
2984 * convert back to the old inode format. If the superblock version
2985 * has been updated, then make the conversion permanent.
2986 */
2990 /*
2991 * Convert it back.
2992 */
2996 /*
2997 * The superblock version has already been bumped,
2998 * so just make the conversion to the new inode
2999 * format permanent.
3000 */
3009 }
3010 }
3017 /*
3018 * We've recorded everything logged in the inode, so we'd
3019 * like to clear the ilf_fields bits so we don't log and
3020 * flush things unnecessarily. However, we can't stop
3021 * logging all this information until the data we've copied
3022 * into the disk buffer is written to disk. If we did we might
3023 * overwrite the copy of the inode in the log with all the
3024 * data after re-logging only part of it, and in the face of
3025 * a crash we wouldn't have all the data we need to recover.
3026 *
3027 * What we do is move the bits to the ili_last_fields field.
3028 * When logging the inode, these bits are moved back to the
3029 * ilf_fields field. In the xfs_iflush_done() routine we
3030 * clear ili_last_fields, since we know that the information
3031 * those bits represent is permanently on disk. As long as
3032 * the flush completes before the inode is logged again, then
3033 * both ilf_fields and ili_last_fields will be cleared.
3034 *
3035 * We can play with the ilf_fields bits here, because the inode
3036 * lock must be held exclusively in order to set bits there
3037 * and the flush lock protects the ili_last_fields bits.
3038 * Set ili_logged so the flush done
3039 * routine can tell whether or not to look in the AIL.
3040 * Also, store the current LSN of the inode so that we can tell
3041 * whether the item has moved in the AIL from xfs_iflush_done().
3042 * In order to read the lsn we need the AIL lock, because
3043 * it is a 64 bit value that cannot be read atomically.
3044 */
3053 /*
3054 * Attach the function xfs_iflush_done to the inode's
3055 * buffer. This will remove the inode from the AIL
3056 * and unlock the inode's flush lock when the inode is
3057 * completely written to disk.
3058 */
3064 /*
3065 * We're flushing an inode which is not in the AIL and has
3066 * not been logged but has i_update_core set. For this
3067 * case we can use a B_DELWRI flush and immediately drop
3068 * the inode flush lock because we can avoid the whole
3069 * AIL state thing. It's OK to drop the flush lock now,
3070 * because we've already locked the buffer and to do anything
3071 * you really need both.
3072 */
3077 }
3079 }
3083 corrupt_out:
3085 }
3087 /*
3088 * Return a pointer to the extent record at file index idx.
3089 */
3090 xfs_bmbt_rec_host_t *
3094 {
3109 }
3110 }
3112 /*
3113 * Insert new item(s) into the extent records for incore inode
3114 * fork 'ifp'. 'count' new items are inserted at index 'idx'.
3115 */
3116 void
3123 {
3133 }
3135 /*
3136 * This is called when the amount of space required for incore file
3137 * extents needs to be increased. The ext_diff parameter stores the
3138 * number of new extents being added and the idx parameter contains
3139 * the extent index where the new extents will be added. If the new
3140 * extents are being appended, then we just need to (re)allocate and
3141 * initialize the space. Otherwise, if the new extents are being
3142 * inserted into the middle of the existing entries, a bit more work
3143 * is required to make room for the new extents to be inserted. The
3144 * caller is responsible for filling in the new extent entries upon
3145 * return.
3146 */
3147 void
3152 {
3161 /*
3162 * If the new number of extents (nextents + ext_diff)
3163 * fits inside the inode, then continue to use the inline
3164 * extent buffer.
3165 */
3172 }
3176 }
3177 /*
3178 * Otherwise use a linear (direct) extent list.
3179 * If the extents are currently inside the inode,
3180 * xfs_iext_realloc_direct will switch us from
3181 * inline to direct extent allocation mode.
3182 */
3190 }
3191 }
3192 /* Indirection array */
3205 }
3206 /* Extents fit in target extent page */
3214 }
3217 }
3218 /* Insert a new extent page */
3222 }
3223 /*
3224 * If extent(s) are being appended to the last page in
3225 * the indirection array and the new extent(s) don't fit
3226 * in the page, then erp is NULL and erp_idx is set to
3227 * the next index needed in the indirection array.
3228 */
3237 erp_idx++;
3238 }
3239 }
3240 }
3241 }
3243 }
3245 /*
3246 * This is called when incore extents are being added to the indirection
3247 * array and the new extents do not fit in the target extent list. The
3248 * erp_idx parameter contains the irec index for the target extent list
3249 * in the indirection array, and the idx parameter contains the extent
3250 * index within the list. The number of extents being added is stored
3251 * in the count parameter.
3252 *
3253 * |-------| |-------|
3254 * | | | | idx - number of extents before idx
3255 * | idx | | count |
3256 * | | | | count - number of extents being inserted at idx
3257 * |-------| |-------|
3258 * | count | | nex2 | nex2 - number of extents after idx + count
3259 * |-------| |-------|
3260 */
3261 void
3267 {
3281 /*
3282 * Save second part of target extent list
3283 * (all extents past */
3291 }
3293 /*
3294 * Add the new extents to the end of the target
3295 * list, then allocate new irec record(s) and
3296 * extent buffer(s) as needed to store the rest
3297 * of the new extents.
3298 */
3305 }
3307 erp_idx++;
3313 }
3315 /* Add nex2 extents back to indirection array */
3317 xfs_extnum_t ext_avail;
3323 /*
3324 * If nex2 extents fit in the current page, append
3325 * nex2_ep after the new extents.
3326 */
3329 }
3330 /*
3331 * Otherwise, check if space is available in the
3332 * next page.
3333 */
3337 erp_idx++;
3338 erp++;
3339 /* Create a hole for nex2 extents */
3342 }
3343 /*
3344 * Final choice, create a new extent page for
3345 * nex2 extents.
3346 */
3348 erp_idx++;
3350 }
3355 }
3356 }
3358 /*
3359 * This is called when the amount of space required for incore file
3360 * extents needs to be decreased. The ext_diff parameter stores the
3361 * number of extents to be removed and the idx parameter contains
3362 * the extent index where the extents will be removed from.
3363 *
3364 * If the amount of space needed has decreased below the linear
3365 * limit, XFS_IEXT_BUFSZ, then switch to using the contiguous
3366 * extent array. Otherwise, use kmem_realloc() to adjust the
3367 * size to what is needed.
3368 */
3369 void
3375 {
3394 }
3396 }
3398 /*
3399 * This removes ext_diff extents from the inline buffer, beginning
3400 * at extent index idx.
3401 */
3402 void
3407 {
3426 }
3427 }
3429 /*
3430 * This removes ext_diff extents from a linear (direct) extent list,
3431 * beginning at extent index idx. If the extents are being removed
3432 * from the end of the list (ie. truncate) then we just need to re-
3433 * allocate the list to remove the extra space. Otherwise, if the
3434 * extents are being removed from the middle of the existing extent
3435 * entries, then we first need to move the extent records beginning
3436 * at idx + ext_diff up in the list to overwrite the records being
3437 * removed, then remove the extra space via kmem_realloc.
3438 */
3439 void
3444 {
3456 }
3457 /* Move extents up in the list (if needed) */
3463 }
3466 /*
3467 * Reallocate the direct extent list. If the extents
3468 * will fit inside the inode then xfs_iext_realloc_direct
3469 * will switch from direct to inline extent allocation
3470 * mode for us.
3471 */
3474 }
3476 /*
3477 * This is called when incore extents are being removed from the
3478 * indirection array and the extents being removed span multiple extent
3479 * buffers. The idx parameter contains the file extent index where we
3480 * want to begin removing extents, and the count parameter contains
3481 * how many extents need to be removed.
3482 *
3483 * |-------| |-------|
3484 * | nex1 | | | nex1 - number of extents before idx
3485 * |-------| | count |
3486 * | | | | count - number of extents being removed at idx
3487 * | count | |-------|
3488 * | | | nex2 | nex2 - number of extents after idx + count
3489 * |-------| |-------|
3490 */
3491 void
3496 {
3513 /*
3514 * Check for deletion of entire list;
3515 * xfs_iext_irec_remove() updates extent offsets.
3516 */
3523 XFS_IEXT_BUFSZ);
3529 }
3530 }
3531 /* Move extents up (if needed) */
3536 }
3537 /* Zero out rest of page */
3540 /* Update remaining counters */
3545 erp_idx++;
3546 erp++;
3547 }
3550 }
3552 /*
3553 * Create, destroy, or resize a linear (direct) block of extents.
3554 */
3555 void
3559 {
3568 /* Free extent records */
3571 }
3572 /* Resize direct extent list and zero any new bytes */
3574 /* Check if extents will fit inside the inode */
3580 }
3583 }
3587 rnew_size,
3589 }
3594 }
3595 }
3596 /*
3597 * Switch from the inline extent buffer to a direct
3598 * extent list. Be sure to include the inline extent
3599 * bytes in new_size.
3600 */
3605 }
3607 }
3610 }
3612 /*
3613 * Switch from linear (direct) extent records to inline buffer.
3614 */
3615 void
3619 {
3622 /*
3623 * The inline buffer was zeroed when we switched
3624 * from inline to direct extent allocation mode,
3625 * so we don't need to clear it here.
3626 */
3632 }
3634 /*
3635 * Switch from inline buffer to linear (direct) extent records.
3636 * new_size should already be rounded up to the next power of 2
3637 * by the caller (when appropriate), so use new_size as it is.
3638 * However, since new_size may be rounded up, we can't update
3639 * if_bytes here. It is the caller's responsibility to update
3640 * if_bytes upon return.
3641 */
3642 void
3646 {
3654 }
3656 }
3658 /*
3659 * Resize an extent indirection array to new_size bytes.
3660 */
3661 STATIC void
3665 {
3680 }
3681 }
3683 /*
3684 * Switch from indirection array to linear (direct) extent allocations.
3685 */
3686 STATIC void
3689 {
3709 }
3710 }
3712 /*
3713 * Free incore file extents.
3714 */
3715 void
3718 {
3726 }
3733 }
3737 }
3739 /*
3740 * Return a pointer to the extent record for file system block bno.
3741 */
3747 {
3762 }
3765 /* Find target extent list */
3773 }
3774 /* Binary search extent records */
3785 /* Convert back to file-based extent index */
3788 }
3791 }
3792 }
3793 /* Convert back to file-based extent index */
3796 }
3802 }
3803 }
3806 }
3808 /*
3809 * Return a pointer to the indirection array entry containing the
3810 * extent record for filesystem block bno. Store the index of the
3811 * target irec in *erp_idxp.
3812 */
3818 {
3842 }
3843 }
3846 }
3848 /*
3849 * Return a pointer to the indirection array entry containing the
3850 * extent record at file extent index *idxp. Store the index of the
3851 * target irec in *erp_idxp and store the page index of the target
3852 * extent record in *idxp.
3853 */
3854 xfs_ext_irec_t *
3860 {
3877 /* Binary search extent irec's */
3893 erp_idx++;
3899 }
3900 }
3904 }
3906 /*
3907 * Allocate and initialize an indirection array once the space needed
3908 * for incore extents increases above XFS_IEXT_BUFSZ.
3909 */
3910 void
3913 {
3929 }
3940 }
3942 /*
3943 * Allocate and initialize a new entry in the indirection array.
3944 */
3945 xfs_ext_irec_t *
3949 {
3957 /* Resize indirection array */
3960 /*
3961 * Move records down in the array so the
3962 * new page can use erp_idx.
3963 */
3967 }
3970 /* Initialize new extent record */
3979 }
3981 /*
3982 * Remove a record from the indirection array.
3983 */
3984 void
3988 {
4000 }
4001 /* Compact extent records */
4005 }
4006 /*
4007 * Manually free the last extent record from the indirection
4008 * array. A call to xfs_iext_realloc_indirect() with a size
4009 * of zero would result in a call to xfs_iext_destroy() which
4010 * would in turn call this function again, creating a nasty
4011 * infinite loop.
4012 */
4018 }
4020 }
4022 /*
4023 * This is called to clean up large amounts of unused memory allocated
4024 * by the indirection array. Before compacting anything though, verify
4025 * that the indirection array is still needed and switch back to the
4026 * linear extent list (or even the inline buffer) if possible. The
4027 * compaction policy is as follows:
4028 *
4029 * Full Compaction: Extents fit into a single page (or inline buffer)
4030 * Partial Compaction: Extents occupy less than 50% of allocated space
4031 * No Compaction: Extents occupy at least 50% of allocated space
4032 */
4033 void
4036 {
4053 }
4054 }
4056 /*
4057 * Combine extents from neighboring extent pages.
4058 */
4059 void
4062 {
4078 /*
4079 * Free page before removing extent record
4080 * so er_extoffs don't get modified in
4081 * xfs_iext_irec_remove.
4082 */
4088 erp_idx++;
4089 }
4090 }
4091 }
4093 /*
4094 * This is called to update the er_extoff field in the indirection
4095 * array when extents have been added or removed from one of the
4096 * extent lists. erp_idx contains the irec index to begin updating
4097 * at and ext_diff contains the number of extents that were added
4098 * or removed.
4099 */
4100 void
4105 {
4113 }
4114 }