2 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
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.
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.
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
20 #include "xfs_types.h"
24 #include "xfs_trans.h"
28 #include "xfs_dmapi.h"
29 #include "xfs_mount.h"
30 #include "xfs_bmap_btree.h"
31 #include "xfs_alloc_btree.h"
32 #include "xfs_ialloc_btree.h"
33 #include "xfs_dir2_sf.h"
34 #include "xfs_attr_sf.h"
35 #include "xfs_dinode.h"
36 #include "xfs_inode.h"
37 #include "xfs_btree.h"
38 #include "xfs_ialloc.h"
39 #include "xfs_alloc.h"
40 #include "xfs_rtalloc.h"
42 #include "xfs_error.h"
44 #include "xfs_quota.h"
45 #include "xfs_fsops.h"
46 #include "xfs_utils.h"
48 STATIC int xfs_mount_log_sb(xfs_mount_t *, __int64_t);
49 STATIC int xfs_uuid_mount(xfs_mount_t *);
50 STATIC void xfs_unmountfs_wait(xfs_mount_t *);
54 STATIC void xfs_icsb_destroy_counters(xfs_mount_t *);
55 STATIC void xfs_icsb_balance_counter(xfs_mount_t *, xfs_sb_field_t,
57 STATIC void xfs_icsb_balance_counter_locked(xfs_mount_t *, xfs_sb_field_t,
59 STATIC int xfs_icsb_modify_counters(xfs_mount_t *, xfs_sb_field_t,
61 STATIC void xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
65 #define xfs_icsb_destroy_counters(mp) do { } while (0)
66 #define xfs_icsb_balance_counter(mp, a, b) do { } while (0)
67 #define xfs_icsb_balance_counter_locked(mp, a, b) do { } while (0)
68 #define xfs_icsb_modify_counters(mp, a, b, c) do { } while (0)
74 short type; /* 0 = integer
75 * 1 = binary / string (no translation)
78 { offsetof(xfs_sb_t, sb_magicnum), 0 },
79 { offsetof(xfs_sb_t, sb_blocksize), 0 },
80 { offsetof(xfs_sb_t, sb_dblocks), 0 },
81 { offsetof(xfs_sb_t, sb_rblocks), 0 },
82 { offsetof(xfs_sb_t, sb_rextents), 0 },
83 { offsetof(xfs_sb_t, sb_uuid), 1 },
84 { offsetof(xfs_sb_t, sb_logstart), 0 },
85 { offsetof(xfs_sb_t, sb_rootino), 0 },
86 { offsetof(xfs_sb_t, sb_rbmino), 0 },
87 { offsetof(xfs_sb_t, sb_rsumino), 0 },
88 { offsetof(xfs_sb_t, sb_rextsize), 0 },
89 { offsetof(xfs_sb_t, sb_agblocks), 0 },
90 { offsetof(xfs_sb_t, sb_agcount), 0 },
91 { offsetof(xfs_sb_t, sb_rbmblocks), 0 },
92 { offsetof(xfs_sb_t, sb_logblocks), 0 },
93 { offsetof(xfs_sb_t, sb_versionnum), 0 },
94 { offsetof(xfs_sb_t, sb_sectsize), 0 },
95 { offsetof(xfs_sb_t, sb_inodesize), 0 },
96 { offsetof(xfs_sb_t, sb_inopblock), 0 },
97 { offsetof(xfs_sb_t, sb_fname[0]), 1 },
98 { offsetof(xfs_sb_t, sb_blocklog), 0 },
99 { offsetof(xfs_sb_t, sb_sectlog), 0 },
100 { offsetof(xfs_sb_t, sb_inodelog), 0 },
101 { offsetof(xfs_sb_t, sb_inopblog), 0 },
102 { offsetof(xfs_sb_t, sb_agblklog), 0 },
103 { offsetof(xfs_sb_t, sb_rextslog), 0 },
104 { offsetof(xfs_sb_t, sb_inprogress), 0 },
105 { offsetof(xfs_sb_t, sb_imax_pct), 0 },
106 { offsetof(xfs_sb_t, sb_icount), 0 },
107 { offsetof(xfs_sb_t, sb_ifree), 0 },
108 { offsetof(xfs_sb_t, sb_fdblocks), 0 },
109 { offsetof(xfs_sb_t, sb_frextents), 0 },
110 { offsetof(xfs_sb_t, sb_uquotino), 0 },
111 { offsetof(xfs_sb_t, sb_gquotino), 0 },
112 { offsetof(xfs_sb_t, sb_qflags), 0 },
113 { offsetof(xfs_sb_t, sb_flags), 0 },
114 { offsetof(xfs_sb_t, sb_shared_vn), 0 },
115 { offsetof(xfs_sb_t, sb_inoalignmt), 0 },
116 { offsetof(xfs_sb_t, sb_unit), 0 },
117 { offsetof(xfs_sb_t, sb_width), 0 },
118 { offsetof(xfs_sb_t, sb_dirblklog), 0 },
119 { offsetof(xfs_sb_t, sb_logsectlog), 0 },
120 { offsetof(xfs_sb_t, sb_logsectsize),0 },
121 { offsetof(xfs_sb_t, sb_logsunit), 0 },
122 { offsetof(xfs_sb_t, sb_features2), 0 },
123 { offsetof(xfs_sb_t, sb_bad_features2), 0 },
124 { sizeof(xfs_sb_t), 0 }
128 * Return a pointer to an initialized xfs_mount structure.
135 mp = kmem_zalloc(sizeof(xfs_mount_t), KM_SLEEP);
137 if (xfs_icsb_init_counters(mp)) {
138 mp->m_flags |= XFS_MOUNT_NO_PERCPU_SB;
141 spin_lock_init(&mp->m_sb_lock);
142 mutex_init(&mp->m_ilock);
143 mutex_init(&mp->m_growlock);
144 atomic_set(&mp->m_active_trans, 0);
150 * Free up the resources associated with a mount structure. Assume that
151 * the structure was initially zeroed, so we can tell which fields got
161 for (agno = 0; agno < mp->m_maxagi; agno++)
162 if (mp->m_perag[agno].pagb_list)
163 kmem_free(mp->m_perag[agno].pagb_list);
164 kmem_free(mp->m_perag);
167 spinlock_destroy(&mp->m_ail_lock);
168 spinlock_destroy(&mp->m_sb_lock);
169 mutex_destroy(&mp->m_ilock);
170 mutex_destroy(&mp->m_growlock);
174 if (mp->m_fsname != NULL)
175 kmem_free(mp->m_fsname);
176 if (mp->m_rtname != NULL)
177 kmem_free(mp->m_rtname);
178 if (mp->m_logname != NULL)
179 kmem_free(mp->m_logname);
181 xfs_icsb_destroy_counters(mp);
185 * Check size of device based on the (data/realtime) block count.
186 * Note: this check is used by the growfs code as well as mount.
189 xfs_sb_validate_fsb_count(
193 ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
194 ASSERT(sbp->sb_blocklog >= BBSHIFT);
196 #if XFS_BIG_BLKNOS /* Limited by ULONG_MAX of page cache index */
197 if (nblocks >> (PAGE_CACHE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
199 #else /* Limited by UINT_MAX of sectors */
200 if (nblocks << (sbp->sb_blocklog - BBSHIFT) > UINT_MAX)
207 * Check the validity of the SB found.
210 xfs_mount_validate_sb(
216 * If the log device and data device have the
217 * same device number, the log is internal.
218 * Consequently, the sb_logstart should be non-zero. If
219 * we have a zero sb_logstart in this case, we may be trying to mount
220 * a volume filesystem in a non-volume manner.
222 if (sbp->sb_magicnum != XFS_SB_MAGIC) {
223 xfs_fs_mount_cmn_err(flags, "bad magic number");
224 return XFS_ERROR(EWRONGFS);
227 if (!xfs_sb_good_version(sbp)) {
228 xfs_fs_mount_cmn_err(flags, "bad version");
229 return XFS_ERROR(EWRONGFS);
233 sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
234 xfs_fs_mount_cmn_err(flags,
235 "filesystem is marked as having an external log; "
236 "specify logdev on the\nmount command line.");
237 return XFS_ERROR(EINVAL);
241 sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
242 xfs_fs_mount_cmn_err(flags,
243 "filesystem is marked as having an internal log; "
244 "do not specify logdev on\nthe mount command line.");
245 return XFS_ERROR(EINVAL);
249 * More sanity checking. These were stolen directly from
253 sbp->sb_agcount <= 0 ||
254 sbp->sb_sectsize < XFS_MIN_SECTORSIZE ||
255 sbp->sb_sectsize > XFS_MAX_SECTORSIZE ||
256 sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG ||
257 sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG ||
258 sbp->sb_blocksize < XFS_MIN_BLOCKSIZE ||
259 sbp->sb_blocksize > XFS_MAX_BLOCKSIZE ||
260 sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG ||
261 sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG ||
262 sbp->sb_inodesize < XFS_DINODE_MIN_SIZE ||
263 sbp->sb_inodesize > XFS_DINODE_MAX_SIZE ||
264 sbp->sb_inodelog < XFS_DINODE_MIN_LOG ||
265 sbp->sb_inodelog > XFS_DINODE_MAX_LOG ||
266 (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) ||
267 (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) ||
268 (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) ||
269 (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */))) {
270 xfs_fs_mount_cmn_err(flags, "SB sanity check 1 failed");
271 return XFS_ERROR(EFSCORRUPTED);
275 * Sanity check AG count, size fields against data size field
278 sbp->sb_dblocks == 0 ||
280 (xfs_drfsbno_t)sbp->sb_agcount * sbp->sb_agblocks ||
281 sbp->sb_dblocks < (xfs_drfsbno_t)(sbp->sb_agcount - 1) *
282 sbp->sb_agblocks + XFS_MIN_AG_BLOCKS)) {
283 xfs_fs_mount_cmn_err(flags, "SB sanity check 2 failed");
284 return XFS_ERROR(EFSCORRUPTED);
287 if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) ||
288 xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) {
289 xfs_fs_mount_cmn_err(flags,
290 "file system too large to be mounted on this system.");
291 return XFS_ERROR(E2BIG);
294 if (unlikely(sbp->sb_inprogress)) {
295 xfs_fs_mount_cmn_err(flags, "file system busy");
296 return XFS_ERROR(EFSCORRUPTED);
300 * Version 1 directory format has never worked on Linux.
302 if (unlikely(!xfs_sb_version_hasdirv2(sbp))) {
303 xfs_fs_mount_cmn_err(flags,
304 "file system using version 1 directory format");
305 return XFS_ERROR(ENOSYS);
309 * Until this is fixed only page-sized or smaller data blocks work.
311 if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) {
312 xfs_fs_mount_cmn_err(flags,
313 "file system with blocksize %d bytes",
315 xfs_fs_mount_cmn_err(flags,
316 "only pagesize (%ld) or less will currently work.",
318 return XFS_ERROR(ENOSYS);
325 xfs_initialize_perag_icache(
328 if (!pag->pag_ici_init) {
329 rwlock_init(&pag->pag_ici_lock);
330 INIT_RADIX_TREE(&pag->pag_ici_root, GFP_ATOMIC);
331 pag->pag_ici_init = 1;
336 xfs_initialize_perag(
338 xfs_agnumber_t agcount)
340 xfs_agnumber_t index, max_metadata;
344 xfs_sb_t *sbp = &mp->m_sb;
345 xfs_ino_t max_inum = XFS_MAXINUMBER_32;
347 /* Check to see if the filesystem can overflow 32 bit inodes */
348 agino = XFS_OFFBNO_TO_AGINO(mp, sbp->sb_agblocks - 1, 0);
349 ino = XFS_AGINO_TO_INO(mp, agcount - 1, agino);
351 /* Clear the mount flag if no inode can overflow 32 bits
352 * on this filesystem, or if specifically requested..
354 if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && ino > max_inum) {
355 mp->m_flags |= XFS_MOUNT_32BITINODES;
357 mp->m_flags &= ~XFS_MOUNT_32BITINODES;
360 /* If we can overflow then setup the ag headers accordingly */
361 if (mp->m_flags & XFS_MOUNT_32BITINODES) {
362 /* Calculate how much should be reserved for inodes to
363 * meet the max inode percentage.
365 if (mp->m_maxicount) {
368 icount = sbp->sb_dblocks * sbp->sb_imax_pct;
370 icount += sbp->sb_agblocks - 1;
371 do_div(icount, sbp->sb_agblocks);
372 max_metadata = icount;
374 max_metadata = agcount;
376 for (index = 0; index < agcount; index++) {
377 ino = XFS_AGINO_TO_INO(mp, index, agino);
378 if (ino > max_inum) {
383 /* This ag is preferred for inodes */
384 pag = &mp->m_perag[index];
385 pag->pagi_inodeok = 1;
386 if (index < max_metadata)
387 pag->pagf_metadata = 1;
388 xfs_initialize_perag_icache(pag);
391 /* Setup default behavior for smaller filesystems */
392 for (index = 0; index < agcount; index++) {
393 pag = &mp->m_perag[index];
394 pag->pagi_inodeok = 1;
395 xfs_initialize_perag_icache(pag);
406 to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
407 to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
408 to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
409 to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
410 to->sb_rextents = be64_to_cpu(from->sb_rextents);
411 memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
412 to->sb_logstart = be64_to_cpu(from->sb_logstart);
413 to->sb_rootino = be64_to_cpu(from->sb_rootino);
414 to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
415 to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
416 to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
417 to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
418 to->sb_agcount = be32_to_cpu(from->sb_agcount);
419 to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
420 to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
421 to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
422 to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
423 to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
424 to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
425 memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
426 to->sb_blocklog = from->sb_blocklog;
427 to->sb_sectlog = from->sb_sectlog;
428 to->sb_inodelog = from->sb_inodelog;
429 to->sb_inopblog = from->sb_inopblog;
430 to->sb_agblklog = from->sb_agblklog;
431 to->sb_rextslog = from->sb_rextslog;
432 to->sb_inprogress = from->sb_inprogress;
433 to->sb_imax_pct = from->sb_imax_pct;
434 to->sb_icount = be64_to_cpu(from->sb_icount);
435 to->sb_ifree = be64_to_cpu(from->sb_ifree);
436 to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
437 to->sb_frextents = be64_to_cpu(from->sb_frextents);
438 to->sb_uquotino = be64_to_cpu(from->sb_uquotino);
439 to->sb_gquotino = be64_to_cpu(from->sb_gquotino);
440 to->sb_qflags = be16_to_cpu(from->sb_qflags);
441 to->sb_flags = from->sb_flags;
442 to->sb_shared_vn = from->sb_shared_vn;
443 to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt);
444 to->sb_unit = be32_to_cpu(from->sb_unit);
445 to->sb_width = be32_to_cpu(from->sb_width);
446 to->sb_dirblklog = from->sb_dirblklog;
447 to->sb_logsectlog = from->sb_logsectlog;
448 to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize);
449 to->sb_logsunit = be32_to_cpu(from->sb_logsunit);
450 to->sb_features2 = be32_to_cpu(from->sb_features2);
451 to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2);
455 * Copy in core superblock to ondisk one.
457 * The fields argument is mask of superblock fields to copy.
465 xfs_caddr_t to_ptr = (xfs_caddr_t)to;
466 xfs_caddr_t from_ptr = (xfs_caddr_t)from;
476 f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
477 first = xfs_sb_info[f].offset;
478 size = xfs_sb_info[f + 1].offset - first;
480 ASSERT(xfs_sb_info[f].type == 0 || xfs_sb_info[f].type == 1);
482 if (size == 1 || xfs_sb_info[f].type == 1) {
483 memcpy(to_ptr + first, from_ptr + first, size);
487 *(__be16 *)(to_ptr + first) =
488 cpu_to_be16(*(__u16 *)(from_ptr + first));
491 *(__be32 *)(to_ptr + first) =
492 cpu_to_be32(*(__u32 *)(from_ptr + first));
495 *(__be64 *)(to_ptr + first) =
496 cpu_to_be64(*(__u64 *)(from_ptr + first));
503 fields &= ~(1LL << f);
510 * Does the initial read of the superblock.
513 xfs_readsb(xfs_mount_t *mp, int flags)
515 unsigned int sector_size;
516 unsigned int extra_flags;
520 ASSERT(mp->m_sb_bp == NULL);
521 ASSERT(mp->m_ddev_targp != NULL);
524 * Allocate a (locked) buffer to hold the superblock.
525 * This will be kept around at all times to optimize
526 * access to the superblock.
528 sector_size = xfs_getsize_buftarg(mp->m_ddev_targp);
529 extra_flags = XFS_BUF_LOCK | XFS_BUF_MANAGE | XFS_BUF_MAPPED;
531 bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR,
532 BTOBB(sector_size), extra_flags);
533 if (!bp || XFS_BUF_ISERROR(bp)) {
534 xfs_fs_mount_cmn_err(flags, "SB read failed");
535 error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
538 ASSERT(XFS_BUF_ISBUSY(bp));
539 ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
542 * Initialize the mount structure from the superblock.
543 * But first do some basic consistency checking.
545 xfs_sb_from_disk(&mp->m_sb, XFS_BUF_TO_SBP(bp));
547 error = xfs_mount_validate_sb(mp, &(mp->m_sb), flags);
549 xfs_fs_mount_cmn_err(flags, "SB validate failed");
554 * We must be able to do sector-sized and sector-aligned IO.
556 if (sector_size > mp->m_sb.sb_sectsize) {
557 xfs_fs_mount_cmn_err(flags,
558 "device supports only %u byte sectors (not %u)",
559 sector_size, mp->m_sb.sb_sectsize);
565 * If device sector size is smaller than the superblock size,
566 * re-read the superblock so the buffer is correctly sized.
568 if (sector_size < mp->m_sb.sb_sectsize) {
569 XFS_BUF_UNMANAGE(bp);
571 sector_size = mp->m_sb.sb_sectsize;
572 bp = xfs_buf_read_flags(mp->m_ddev_targp, XFS_SB_DADDR,
573 BTOBB(sector_size), extra_flags);
574 if (!bp || XFS_BUF_ISERROR(bp)) {
575 xfs_fs_mount_cmn_err(flags, "SB re-read failed");
576 error = bp ? XFS_BUF_GETERROR(bp) : ENOMEM;
579 ASSERT(XFS_BUF_ISBUSY(bp));
580 ASSERT(XFS_BUF_VALUSEMA(bp) <= 0);
583 /* Initialize per-cpu counters */
584 xfs_icsb_reinit_counters(mp);
588 ASSERT(XFS_BUF_VALUSEMA(bp) > 0);
593 XFS_BUF_UNMANAGE(bp);
603 * Mount initialization code establishing various mount
604 * fields from the superblock associated with the given
608 xfs_mount_common(xfs_mount_t *mp, xfs_sb_t *sbp)
612 mp->m_agfrotor = mp->m_agirotor = 0;
613 spin_lock_init(&mp->m_agirotor_lock);
614 mp->m_maxagi = mp->m_sb.sb_agcount;
615 mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
616 mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
617 mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
618 mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
619 mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
620 mp->m_litino = sbp->sb_inodesize -
621 ((uint)sizeof(xfs_dinode_core_t) + (uint)sizeof(xfs_agino_t));
622 mp->m_blockmask = sbp->sb_blocksize - 1;
623 mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
624 mp->m_blockwmask = mp->m_blockwsize - 1;
625 INIT_LIST_HEAD(&mp->m_del_inodes);
628 * Setup for attributes, in case they get created.
629 * This value is for inodes getting attributes for the first time,
630 * the per-inode value is for old attribute values.
632 ASSERT(sbp->sb_inodesize >= 256 && sbp->sb_inodesize <= 2048);
633 switch (sbp->sb_inodesize) {
635 mp->m_attroffset = XFS_LITINO(mp) -
636 XFS_BMDR_SPACE_CALC(MINABTPTRS);
641 mp->m_attroffset = XFS_BMDR_SPACE_CALC(6 * MINABTPTRS);
646 ASSERT(mp->m_attroffset < XFS_LITINO(mp));
648 for (i = 0; i < 2; i++) {
649 mp->m_alloc_mxr[i] = XFS_BTREE_BLOCK_MAXRECS(sbp->sb_blocksize,
651 mp->m_alloc_mnr[i] = XFS_BTREE_BLOCK_MINRECS(sbp->sb_blocksize,
654 for (i = 0; i < 2; i++) {
655 mp->m_bmap_dmxr[i] = XFS_BTREE_BLOCK_MAXRECS(sbp->sb_blocksize,
657 mp->m_bmap_dmnr[i] = XFS_BTREE_BLOCK_MINRECS(sbp->sb_blocksize,
660 for (i = 0; i < 2; i++) {
661 mp->m_inobt_mxr[i] = XFS_BTREE_BLOCK_MAXRECS(sbp->sb_blocksize,
663 mp->m_inobt_mnr[i] = XFS_BTREE_BLOCK_MINRECS(sbp->sb_blocksize,
667 mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
668 mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
670 mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog;
674 * xfs_initialize_perag_data
676 * Read in each per-ag structure so we can count up the number of
677 * allocated inodes, free inodes and used filesystem blocks as this
678 * information is no longer persistent in the superblock. Once we have
679 * this information, write it into the in-core superblock structure.
682 xfs_initialize_perag_data(xfs_mount_t *mp, xfs_agnumber_t agcount)
684 xfs_agnumber_t index;
686 xfs_sb_t *sbp = &mp->m_sb;
690 uint64_t bfreelst = 0;
694 for (index = 0; index < agcount; index++) {
696 * read the agf, then the agi. This gets us
697 * all the inforamtion we need and populates the
698 * per-ag structures for us.
700 error = xfs_alloc_pagf_init(mp, NULL, index, 0);
704 error = xfs_ialloc_pagi_init(mp, NULL, index);
707 pag = &mp->m_perag[index];
708 ifree += pag->pagi_freecount;
709 ialloc += pag->pagi_count;
710 bfree += pag->pagf_freeblks;
711 bfreelst += pag->pagf_flcount;
712 btree += pag->pagf_btreeblks;
715 * Overwrite incore superblock counters with just-read data
717 spin_lock(&mp->m_sb_lock);
718 sbp->sb_ifree = ifree;
719 sbp->sb_icount = ialloc;
720 sbp->sb_fdblocks = bfree + bfreelst + btree;
721 spin_unlock(&mp->m_sb_lock);
723 /* Fixup the per-cpu counters as well. */
724 xfs_icsb_reinit_counters(mp);
730 * Update alignment values based on mount options and sb values
733 xfs_update_alignment(xfs_mount_t *mp, int mfsi_flags, __uint64_t *update_flags)
735 xfs_sb_t *sbp = &(mp->m_sb);
737 if (mp->m_dalign && !(mfsi_flags & XFS_MFSI_SECOND)) {
739 * If stripe unit and stripe width are not multiples
740 * of the fs blocksize turn off alignment.
742 if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
743 (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
744 if (mp->m_flags & XFS_MOUNT_RETERR) {
746 "XFS: alignment check 1 failed");
747 return XFS_ERROR(EINVAL);
749 mp->m_dalign = mp->m_swidth = 0;
752 * Convert the stripe unit and width to FSBs.
754 mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
755 if (mp->m_dalign && (sbp->sb_agblocks % mp->m_dalign)) {
756 if (mp->m_flags & XFS_MOUNT_RETERR) {
757 return XFS_ERROR(EINVAL);
759 xfs_fs_cmn_err(CE_WARN, mp,
760 "stripe alignment turned off: sunit(%d)/swidth(%d) incompatible with agsize(%d)",
761 mp->m_dalign, mp->m_swidth,
766 } else if (mp->m_dalign) {
767 mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
769 if (mp->m_flags & XFS_MOUNT_RETERR) {
770 xfs_fs_cmn_err(CE_WARN, mp,
771 "stripe alignment turned off: sunit(%d) less than bsize(%d)",
774 return XFS_ERROR(EINVAL);
781 * Update superblock with new values
784 if (xfs_sb_version_hasdalign(sbp)) {
785 if (sbp->sb_unit != mp->m_dalign) {
786 sbp->sb_unit = mp->m_dalign;
787 *update_flags |= XFS_SB_UNIT;
789 if (sbp->sb_width != mp->m_swidth) {
790 sbp->sb_width = mp->m_swidth;
791 *update_flags |= XFS_SB_WIDTH;
794 } else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
795 xfs_sb_version_hasdalign(&mp->m_sb)) {
796 mp->m_dalign = sbp->sb_unit;
797 mp->m_swidth = sbp->sb_width;
804 * Set the maximum inode count for this filesystem
807 xfs_set_maxicount(xfs_mount_t *mp)
809 xfs_sb_t *sbp = &(mp->m_sb);
812 if (sbp->sb_imax_pct) {
814 * Make sure the maximum inode count is a multiple
815 * of the units we allocate inodes in.
817 icount = sbp->sb_dblocks * sbp->sb_imax_pct;
819 do_div(icount, mp->m_ialloc_blks);
820 mp->m_maxicount = (icount * mp->m_ialloc_blks) <<
828 * Set the default minimum read and write sizes unless
829 * already specified in a mount option.
830 * We use smaller I/O sizes when the file system
831 * is being used for NFS service (wsync mount option).
834 xfs_set_rw_sizes(xfs_mount_t *mp)
836 xfs_sb_t *sbp = &(mp->m_sb);
837 int readio_log, writeio_log;
839 if (!(mp->m_flags & XFS_MOUNT_DFLT_IOSIZE)) {
840 if (mp->m_flags & XFS_MOUNT_WSYNC) {
841 readio_log = XFS_WSYNC_READIO_LOG;
842 writeio_log = XFS_WSYNC_WRITEIO_LOG;
844 readio_log = XFS_READIO_LOG_LARGE;
845 writeio_log = XFS_WRITEIO_LOG_LARGE;
848 readio_log = mp->m_readio_log;
849 writeio_log = mp->m_writeio_log;
852 if (sbp->sb_blocklog > readio_log) {
853 mp->m_readio_log = sbp->sb_blocklog;
855 mp->m_readio_log = readio_log;
857 mp->m_readio_blocks = 1 << (mp->m_readio_log - sbp->sb_blocklog);
858 if (sbp->sb_blocklog > writeio_log) {
859 mp->m_writeio_log = sbp->sb_blocklog;
861 mp->m_writeio_log = writeio_log;
863 mp->m_writeio_blocks = 1 << (mp->m_writeio_log - sbp->sb_blocklog);
867 * Set whether we're using inode alignment.
870 xfs_set_inoalignment(xfs_mount_t *mp)
872 if (xfs_sb_version_hasalign(&mp->m_sb) &&
873 mp->m_sb.sb_inoalignmt >=
874 XFS_B_TO_FSBT(mp, mp->m_inode_cluster_size))
875 mp->m_inoalign_mask = mp->m_sb.sb_inoalignmt - 1;
877 mp->m_inoalign_mask = 0;
879 * If we are using stripe alignment, check whether
880 * the stripe unit is a multiple of the inode alignment
882 if (mp->m_dalign && mp->m_inoalign_mask &&
883 !(mp->m_dalign & mp->m_inoalign_mask))
884 mp->m_sinoalign = mp->m_dalign;
890 * Check that the data (and log if separate) are an ok size.
893 xfs_check_sizes(xfs_mount_t *mp, int mfsi_flags)
899 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_dblocks);
900 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_dblocks) {
901 cmn_err(CE_WARN, "XFS: size check 1 failed");
902 return XFS_ERROR(E2BIG);
904 error = xfs_read_buf(mp, mp->m_ddev_targp,
905 d - XFS_FSS_TO_BB(mp, 1),
906 XFS_FSS_TO_BB(mp, 1), 0, &bp);
910 cmn_err(CE_WARN, "XFS: size check 2 failed");
912 error = XFS_ERROR(E2BIG);
916 if (((mfsi_flags & XFS_MFSI_CLIENT) == 0) &&
917 mp->m_logdev_targp != mp->m_ddev_targp) {
918 d = (xfs_daddr_t)XFS_FSB_TO_BB(mp, mp->m_sb.sb_logblocks);
919 if (XFS_BB_TO_FSB(mp, d) != mp->m_sb.sb_logblocks) {
920 cmn_err(CE_WARN, "XFS: size check 3 failed");
921 return XFS_ERROR(E2BIG);
923 error = xfs_read_buf(mp, mp->m_logdev_targp,
924 d - XFS_FSB_TO_BB(mp, 1),
925 XFS_FSB_TO_BB(mp, 1), 0, &bp);
929 cmn_err(CE_WARN, "XFS: size check 3 failed");
931 error = XFS_ERROR(E2BIG);
941 * This function does the following on an initial mount of a file system:
942 * - reads the superblock from disk and init the mount struct
943 * - if we're a 32-bit kernel, do a size check on the superblock
944 * so we don't mount terabyte filesystems
945 * - init mount struct realtime fields
946 * - allocate inode hash table for fs
947 * - init directory manager
948 * - perform recovery and init the log manager
955 xfs_sb_t *sbp = &(mp->m_sb);
958 __int64_t update_flags = 0LL;
959 uint quotamount, quotaflags;
961 int uuid_mounted = 0;
964 xfs_mount_common(mp, sbp);
967 * Check for a mismatched features2 values. Older kernels
968 * read & wrote into the wrong sb offset for sb_features2
969 * on some platforms due to xfs_sb_t not being 64bit size aligned
970 * when sb_features2 was added, which made older superblock
971 * reading/writing routines swap it as a 64-bit value.
973 * For backwards compatibility, we make both slots equal.
975 * If we detect a mismatched field, we OR the set bits into the
976 * existing features2 field in case it has already been modified; we
977 * don't want to lose any features. We then update the bad location
978 * with the ORed value so that older kernels will see any features2
979 * flags, and mark the two fields as needing updates once the
980 * transaction subsystem is online.
982 if (xfs_sb_has_mismatched_features2(sbp)) {
984 "XFS: correcting sb_features alignment problem");
985 sbp->sb_features2 |= sbp->sb_bad_features2;
986 sbp->sb_bad_features2 = sbp->sb_features2;
987 update_flags |= XFS_SB_FEATURES2 | XFS_SB_BAD_FEATURES2;
990 * Re-check for ATTR2 in case it was found in bad_features2
993 if (xfs_sb_version_hasattr2(&mp->m_sb) &&
994 !(mp->m_flags & XFS_MOUNT_NOATTR2))
995 mp->m_flags |= XFS_MOUNT_ATTR2;
998 if (xfs_sb_version_hasattr2(&mp->m_sb) &&
999 (mp->m_flags & XFS_MOUNT_NOATTR2)) {
1000 xfs_sb_version_removeattr2(&mp->m_sb);
1001 update_flags |= XFS_SB_FEATURES2;
1003 /* update sb_versionnum for the clearing of the morebits */
1004 if (!sbp->sb_features2)
1005 update_flags |= XFS_SB_VERSIONNUM;
1009 * Check if sb_agblocks is aligned at stripe boundary
1010 * If sb_agblocks is NOT aligned turn off m_dalign since
1011 * allocator alignment is within an ag, therefore ag has
1012 * to be aligned at stripe boundary.
1014 error = xfs_update_alignment(mp, mfsi_flags, &update_flags);
1018 xfs_alloc_compute_maxlevels(mp);
1019 xfs_bmap_compute_maxlevels(mp, XFS_DATA_FORK);
1020 xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
1021 xfs_ialloc_compute_maxlevels(mp);
1023 xfs_set_maxicount(mp);
1025 mp->m_maxioffset = xfs_max_file_offset(sbp->sb_blocklog);
1028 * XFS uses the uuid from the superblock as the unique
1029 * identifier for fsid. We can not use the uuid from the volume
1030 * since a single partition filesystem is identical to a single
1031 * partition volume/filesystem.
1033 if ((mfsi_flags & XFS_MFSI_SECOND) == 0 &&
1034 (mp->m_flags & XFS_MOUNT_NOUUID) == 0) {
1035 if (xfs_uuid_mount(mp)) {
1036 error = XFS_ERROR(EINVAL);
1043 * Set the minimum read and write sizes
1045 xfs_set_rw_sizes(mp);
1048 * Set the inode cluster size.
1049 * This may still be overridden by the file system
1050 * block size if it is larger than the chosen cluster size.
1052 mp->m_inode_cluster_size = XFS_INODE_BIG_CLUSTER_SIZE;
1055 * Set inode alignment fields
1057 xfs_set_inoalignment(mp);
1060 * Check that the data (and log if separate) are an ok size.
1062 error = xfs_check_sizes(mp, mfsi_flags);
1067 * Initialize realtime fields in the mount structure
1069 error = xfs_rtmount_init(mp);
1071 cmn_err(CE_WARN, "XFS: RT mount failed");
1076 * For client case we are done now
1078 if (mfsi_flags & XFS_MFSI_CLIENT) {
1083 * Copies the low order bits of the timestamp and the randomly
1084 * set "sequence" number out of a UUID.
1086 uuid_getnodeuniq(&sbp->sb_uuid, mp->m_fixedfsid);
1088 mp->m_dmevmask = 0; /* not persistent; set after each mount */
1093 * Initialize the attribute manager's entries.
1095 mp->m_attr_magicpct = (mp->m_sb.sb_blocksize * 37) / 100;
1098 * Initialize the precomputed transaction reservations values.
1103 * Allocate and initialize the per-ag data.
1105 init_rwsem(&mp->m_peraglock);
1107 kmem_zalloc(sbp->sb_agcount * sizeof(xfs_perag_t), KM_SLEEP);
1109 mp->m_maxagi = xfs_initialize_perag(mp, sbp->sb_agcount);
1112 * log's mount-time initialization. Perform 1st part recovery if needed
1114 if (likely(sbp->sb_logblocks > 0)) { /* check for volume case */
1115 error = xfs_log_mount(mp, mp->m_logdev_targp,
1116 XFS_FSB_TO_DADDR(mp, sbp->sb_logstart),
1117 XFS_FSB_TO_BB(mp, sbp->sb_logblocks));
1119 cmn_err(CE_WARN, "XFS: log mount failed");
1122 } else { /* No log has been defined */
1123 cmn_err(CE_WARN, "XFS: no log defined");
1124 XFS_ERROR_REPORT("xfs_mountfs_int(1)", XFS_ERRLEVEL_LOW, mp);
1125 error = XFS_ERROR(EFSCORRUPTED);
1130 * Now the log is mounted, we know if it was an unclean shutdown or
1131 * not. If it was, with the first phase of recovery has completed, we
1132 * have consistent AG blocks on disk. We have not recovered EFIs yet,
1133 * but they are recovered transactionally in the second recovery phase
1136 * Hence we can safely re-initialise incore superblock counters from
1137 * the per-ag data. These may not be correct if the filesystem was not
1138 * cleanly unmounted, so we need to wait for recovery to finish before
1141 * If the filesystem was cleanly unmounted, then we can trust the
1142 * values in the superblock to be correct and we don't need to do
1145 * If we are currently making the filesystem, the initialisation will
1146 * fail as the perag data is in an undefined state.
1149 if (xfs_sb_version_haslazysbcount(&mp->m_sb) &&
1150 !XFS_LAST_UNMOUNT_WAS_CLEAN(mp) &&
1151 !mp->m_sb.sb_inprogress) {
1152 error = xfs_initialize_perag_data(mp, sbp->sb_agcount);
1158 * Get and sanity-check the root inode.
1159 * Save the pointer to it in the mount structure.
1161 error = xfs_iget(mp, NULL, sbp->sb_rootino, 0, XFS_ILOCK_EXCL, &rip, 0);
1163 cmn_err(CE_WARN, "XFS: failed to read root inode");
1167 ASSERT(rip != NULL);
1169 if (unlikely((rip->i_d.di_mode & S_IFMT) != S_IFDIR)) {
1170 cmn_err(CE_WARN, "XFS: corrupted root inode");
1171 cmn_err(CE_WARN, "Device %s - root %llu is not a directory",
1172 XFS_BUFTARG_NAME(mp->m_ddev_targp),
1173 (unsigned long long)rip->i_ino);
1174 xfs_iunlock(rip, XFS_ILOCK_EXCL);
1175 XFS_ERROR_REPORT("xfs_mountfs_int(2)", XFS_ERRLEVEL_LOW,
1177 error = XFS_ERROR(EFSCORRUPTED);
1180 mp->m_rootip = rip; /* save it */
1182 xfs_iunlock(rip, XFS_ILOCK_EXCL);
1185 * Initialize realtime inode pointers in the mount structure
1187 error = xfs_rtmount_inodes(mp);
1190 * Free up the root inode.
1192 cmn_err(CE_WARN, "XFS: failed to read RT inodes");
1197 * If fs is not mounted readonly, then update the superblock changes.
1199 if (update_flags && !(mp->m_flags & XFS_MOUNT_RDONLY)) {
1200 error = xfs_mount_log_sb(mp, update_flags);
1202 cmn_err(CE_WARN, "XFS: failed to write sb changes");
1208 * Initialise the XFS quota management subsystem for this mount
1210 error = XFS_QM_INIT(mp, "amount, "aflags);
1215 * Finish recovering the file system. This part needed to be
1216 * delayed until after the root and real-time bitmap inodes
1217 * were consistently read in.
1219 error = xfs_log_mount_finish(mp, mfsi_flags);
1221 cmn_err(CE_WARN, "XFS: log mount finish failed");
1226 * Complete the quota initialisation, post-log-replay component.
1228 error = XFS_QM_MOUNT(mp, quotamount, quotaflags, mfsi_flags);
1233 * Now we are mounted, reserve a small amount of unused space for
1234 * privileged transactions. This is needed so that transaction
1235 * space required for critical operations can dip into this pool
1236 * when at ENOSPC. This is needed for operations like create with
1237 * attr, unwritten extent conversion at ENOSPC, etc. Data allocations
1238 * are not allowed to use this reserved space.
1240 * We default to 5% or 1024 fsbs of space reserved, whichever is smaller.
1241 * This may drive us straight to ENOSPC on mount, but that implies
1242 * we were already there on the last unmount. Warn if this occurs.
1244 resblks = mp->m_sb.sb_dblocks;
1245 do_div(resblks, 20);
1246 resblks = min_t(__uint64_t, resblks, 1024);
1247 error = xfs_reserve_blocks(mp, &resblks, NULL);
1249 cmn_err(CE_WARN, "XFS: Unable to allocate reserve blocks. "
1250 "Continuing without a reserve pool.");
1256 * Free up the root inode.
1260 xfs_log_unmount_dealloc(mp);
1262 for (agno = 0; agno < sbp->sb_agcount; agno++)
1263 if (mp->m_perag[agno].pagb_list)
1264 kmem_free(mp->m_perag[agno].pagb_list);
1265 kmem_free(mp->m_perag);
1270 uuid_table_remove(&mp->m_sb.sb_uuid);
1277 * This flushes out the inodes,dquots and the superblock, unmounts the
1278 * log and makes sure that incore structures are freed.
1281 xfs_unmountfs(xfs_mount_t *mp, struct cred *cr)
1287 * We can potentially deadlock here if we have an inode cluster
1288 * that has been freed has it's buffer still pinned in memory because
1289 * the transaction is still sitting in a iclog. The stale inodes
1290 * on that buffer will have their flush locks held until the
1291 * transaction hits the disk and the callbacks run. the inode
1292 * flush takes the flush lock unconditionally and with nothing to
1293 * push out the iclog we will never get that unlocked. hence we
1294 * need to force the log first.
1296 xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE | XFS_LOG_SYNC);
1299 XFS_QM_DQPURGEALL(mp, XFS_QMOPT_QUOTALL | XFS_QMOPT_UMOUNTING);
1302 * Flush out the log synchronously so that we know for sure
1303 * that nothing is pinned. This is important because bflush()
1304 * will skip pinned buffers.
1306 xfs_log_force(mp, (xfs_lsn_t)0, XFS_LOG_FORCE | XFS_LOG_SYNC);
1308 xfs_binval(mp->m_ddev_targp);
1309 if (mp->m_rtdev_targp) {
1310 xfs_binval(mp->m_rtdev_targp);
1314 * Unreserve any blocks we have so that when we unmount we don't account
1315 * the reserved free space as used. This is really only necessary for
1316 * lazy superblock counting because it trusts the incore superblock
1317 * counters to be aboslutely correct on clean unmount.
1319 * We don't bother correcting this elsewhere for lazy superblock
1320 * counting because on mount of an unclean filesystem we reconstruct the
1321 * correct counter value and this is irrelevant.
1323 * For non-lazy counter filesystems, this doesn't matter at all because
1324 * we only every apply deltas to the superblock and hence the incore
1325 * value does not matter....
1328 error = xfs_reserve_blocks(mp, &resblks, NULL);
1330 cmn_err(CE_WARN, "XFS: Unable to free reserved block pool. "
1331 "Freespace may not be correct on next mount.");
1333 error = xfs_log_sbcount(mp, 1);
1335 cmn_err(CE_WARN, "XFS: Unable to update superblock counters. "
1336 "Freespace may not be correct on next mount.");
1337 xfs_unmountfs_writesb(mp);
1338 xfs_unmountfs_wait(mp); /* wait for async bufs */
1339 xfs_log_unmount(mp); /* Done! No more fs ops. */
1344 * All inodes from this mount point should be freed.
1346 ASSERT(mp->m_inodes == NULL);
1348 xfs_unmountfs_close(mp, cr);
1349 if ((mp->m_flags & XFS_MOUNT_NOUUID) == 0)
1350 uuid_table_remove(&mp->m_sb.sb_uuid);
1352 #if defined(DEBUG) || defined(INDUCE_IO_ERROR)
1353 xfs_errortag_clearall(mp, 0);
1360 xfs_unmountfs_close(xfs_mount_t *mp, struct cred *cr)
1362 if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
1363 xfs_free_buftarg(mp->m_logdev_targp, 1);
1364 if (mp->m_rtdev_targp)
1365 xfs_free_buftarg(mp->m_rtdev_targp, 1);
1366 xfs_free_buftarg(mp->m_ddev_targp, 0);
1370 xfs_unmountfs_wait(xfs_mount_t *mp)
1372 if (mp->m_logdev_targp != mp->m_ddev_targp)
1373 xfs_wait_buftarg(mp->m_logdev_targp);
1374 if (mp->m_rtdev_targp)
1375 xfs_wait_buftarg(mp->m_rtdev_targp);
1376 xfs_wait_buftarg(mp->m_ddev_targp);
1380 xfs_fs_writable(xfs_mount_t *mp)
1382 return !(xfs_test_for_freeze(mp) || XFS_FORCED_SHUTDOWN(mp) ||
1383 (mp->m_flags & XFS_MOUNT_RDONLY));
1389 * Called either periodically to keep the on disk superblock values
1390 * roughly up to date or from unmount to make sure the values are
1391 * correct on a clean unmount.
1393 * Note this code can be called during the process of freezing, so
1394 * we may need to use the transaction allocator which does not not
1395 * block when the transaction subsystem is in its frozen state.
1405 if (!xfs_fs_writable(mp))
1408 xfs_icsb_sync_counters(mp, 0);
1411 * we don't need to do this if we are updating the superblock
1412 * counters on every modification.
1414 if (!xfs_sb_version_haslazysbcount(&mp->m_sb))
1417 tp = _xfs_trans_alloc(mp, XFS_TRANS_SB_COUNT);
1418 error = xfs_trans_reserve(tp, 0, mp->m_sb.sb_sectsize + 128, 0, 0,
1419 XFS_DEFAULT_LOG_COUNT);
1421 xfs_trans_cancel(tp, 0);
1425 xfs_mod_sb(tp, XFS_SB_IFREE | XFS_SB_ICOUNT | XFS_SB_FDBLOCKS);
1427 xfs_trans_set_sync(tp);
1428 error = xfs_trans_commit(tp, 0);
1437 xfs_dsb_t *sb = XFS_BUF_TO_SBP(bp);
1440 if (!(sb->sb_flags & XFS_SBF_READONLY))
1441 sb->sb_flags |= XFS_SBF_READONLY;
1443 version = be16_to_cpu(sb->sb_versionnum);
1444 if ((version & XFS_SB_VERSION_NUMBITS) != XFS_SB_VERSION_4 ||
1445 !(version & XFS_SB_VERSION_SHAREDBIT))
1446 version |= XFS_SB_VERSION_SHAREDBIT;
1447 sb->sb_versionnum = cpu_to_be16(version);
1451 xfs_unmountfs_writesb(xfs_mount_t *mp)
1457 * skip superblock write if fs is read-only, or
1458 * if we are doing a forced umount.
1460 if (!((mp->m_flags & XFS_MOUNT_RDONLY) ||
1461 XFS_FORCED_SHUTDOWN(mp))) {
1463 sbp = xfs_getsb(mp, 0);
1466 * mark shared-readonly if desired
1468 if (mp->m_mk_sharedro)
1469 xfs_mark_shared_ro(mp, sbp);
1471 XFS_BUF_UNDONE(sbp);
1472 XFS_BUF_UNREAD(sbp);
1473 XFS_BUF_UNDELAYWRITE(sbp);
1475 XFS_BUF_UNASYNC(sbp);
1476 ASSERT(XFS_BUF_TARGET(sbp) == mp->m_ddev_targp);
1477 xfsbdstrat(mp, sbp);
1478 error = xfs_iowait(sbp);
1480 xfs_ioerror_alert("xfs_unmountfs_writesb",
1481 mp, sbp, XFS_BUF_ADDR(sbp));
1482 if (error && mp->m_mk_sharedro)
1483 xfs_fs_cmn_err(CE_ALERT, mp, "Superblock write error detected while unmounting. Filesystem may not be marked shared readonly");
1490 * xfs_mod_sb() can be used to copy arbitrary changes to the
1491 * in-core superblock into the superblock buffer to be logged.
1492 * It does not provide the higher level of locking that is
1493 * needed to protect the in-core superblock from concurrent
1497 xfs_mod_sb(xfs_trans_t *tp, __int64_t fields)
1509 bp = xfs_trans_getsb(tp, mp, 0);
1510 first = sizeof(xfs_sb_t);
1513 /* translate/copy */
1515 xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, fields);
1517 /* find modified range */
1519 f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
1520 ASSERT((1LL << f) & XFS_SB_MOD_BITS);
1521 first = xfs_sb_info[f].offset;
1523 f = (xfs_sb_field_t)xfs_highbit64((__uint64_t)fields);
1524 ASSERT((1LL << f) & XFS_SB_MOD_BITS);
1525 last = xfs_sb_info[f + 1].offset - 1;
1527 xfs_trans_log_buf(tp, bp, first, last);
1532 * xfs_mod_incore_sb_unlocked() is a utility routine common used to apply
1533 * a delta to a specified field in the in-core superblock. Simply
1534 * switch on the field indicated and apply the delta to that field.
1535 * Fields are not allowed to dip below zero, so if the delta would
1536 * do this do not apply it and return EINVAL.
1538 * The m_sb_lock must be held when this routine is called.
1541 xfs_mod_incore_sb_unlocked(
1543 xfs_sb_field_t field,
1547 int scounter; /* short counter for 32 bit fields */
1548 long long lcounter; /* long counter for 64 bit fields */
1549 long long res_used, rem;
1552 * With the in-core superblock spin lock held, switch
1553 * on the indicated field. Apply the delta to the
1554 * proper field. If the fields value would dip below
1555 * 0, then do not apply the delta and return EINVAL.
1558 case XFS_SBS_ICOUNT:
1559 lcounter = (long long)mp->m_sb.sb_icount;
1563 return XFS_ERROR(EINVAL);
1565 mp->m_sb.sb_icount = lcounter;
1568 lcounter = (long long)mp->m_sb.sb_ifree;
1572 return XFS_ERROR(EINVAL);
1574 mp->m_sb.sb_ifree = lcounter;
1576 case XFS_SBS_FDBLOCKS:
1577 lcounter = (long long)
1578 mp->m_sb.sb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
1579 res_used = (long long)(mp->m_resblks - mp->m_resblks_avail);
1581 if (delta > 0) { /* Putting blocks back */
1582 if (res_used > delta) {
1583 mp->m_resblks_avail += delta;
1585 rem = delta - res_used;
1586 mp->m_resblks_avail = mp->m_resblks;
1589 } else { /* Taking blocks away */
1594 * If were out of blocks, use any available reserved blocks if
1600 lcounter = (long long)mp->m_resblks_avail + delta;
1602 return XFS_ERROR(ENOSPC);
1604 mp->m_resblks_avail = lcounter;
1606 } else { /* not reserved */
1607 return XFS_ERROR(ENOSPC);
1612 mp->m_sb.sb_fdblocks = lcounter + XFS_ALLOC_SET_ASIDE(mp);
1614 case XFS_SBS_FREXTENTS:
1615 lcounter = (long long)mp->m_sb.sb_frextents;
1618 return XFS_ERROR(ENOSPC);
1620 mp->m_sb.sb_frextents = lcounter;
1622 case XFS_SBS_DBLOCKS:
1623 lcounter = (long long)mp->m_sb.sb_dblocks;
1627 return XFS_ERROR(EINVAL);
1629 mp->m_sb.sb_dblocks = lcounter;
1631 case XFS_SBS_AGCOUNT:
1632 scounter = mp->m_sb.sb_agcount;
1636 return XFS_ERROR(EINVAL);
1638 mp->m_sb.sb_agcount = scounter;
1640 case XFS_SBS_IMAX_PCT:
1641 scounter = mp->m_sb.sb_imax_pct;
1645 return XFS_ERROR(EINVAL);
1647 mp->m_sb.sb_imax_pct = scounter;
1649 case XFS_SBS_REXTSIZE:
1650 scounter = mp->m_sb.sb_rextsize;
1654 return XFS_ERROR(EINVAL);
1656 mp->m_sb.sb_rextsize = scounter;
1658 case XFS_SBS_RBMBLOCKS:
1659 scounter = mp->m_sb.sb_rbmblocks;
1663 return XFS_ERROR(EINVAL);
1665 mp->m_sb.sb_rbmblocks = scounter;
1667 case XFS_SBS_RBLOCKS:
1668 lcounter = (long long)mp->m_sb.sb_rblocks;
1672 return XFS_ERROR(EINVAL);
1674 mp->m_sb.sb_rblocks = lcounter;
1676 case XFS_SBS_REXTENTS:
1677 lcounter = (long long)mp->m_sb.sb_rextents;
1681 return XFS_ERROR(EINVAL);
1683 mp->m_sb.sb_rextents = lcounter;
1685 case XFS_SBS_REXTSLOG:
1686 scounter = mp->m_sb.sb_rextslog;
1690 return XFS_ERROR(EINVAL);
1692 mp->m_sb.sb_rextslog = scounter;
1696 return XFS_ERROR(EINVAL);
1701 * xfs_mod_incore_sb() is used to change a field in the in-core
1702 * superblock structure by the specified delta. This modification
1703 * is protected by the m_sb_lock. Just use the xfs_mod_incore_sb_unlocked()
1704 * routine to do the work.
1709 xfs_sb_field_t field,
1715 /* check for per-cpu counters */
1717 #ifdef HAVE_PERCPU_SB
1718 case XFS_SBS_ICOUNT:
1720 case XFS_SBS_FDBLOCKS:
1721 if (!(mp->m_flags & XFS_MOUNT_NO_PERCPU_SB)) {
1722 status = xfs_icsb_modify_counters(mp, field,
1729 spin_lock(&mp->m_sb_lock);
1730 status = xfs_mod_incore_sb_unlocked(mp, field, delta, rsvd);
1731 spin_unlock(&mp->m_sb_lock);
1739 * xfs_mod_incore_sb_batch() is used to change more than one field
1740 * in the in-core superblock structure at a time. This modification
1741 * is protected by a lock internal to this module. The fields and
1742 * changes to those fields are specified in the array of xfs_mod_sb
1743 * structures passed in.
1745 * Either all of the specified deltas will be applied or none of
1746 * them will. If any modified field dips below 0, then all modifications
1747 * will be backed out and EINVAL will be returned.
1750 xfs_mod_incore_sb_batch(xfs_mount_t *mp, xfs_mod_sb_t *msb, uint nmsb, int rsvd)
1756 * Loop through the array of mod structures and apply each
1757 * individually. If any fail, then back out all those
1758 * which have already been applied. Do all of this within
1759 * the scope of the m_sb_lock so that all of the changes will
1762 spin_lock(&mp->m_sb_lock);
1764 for (msbp = &msbp[0]; msbp < (msb + nmsb); msbp++) {
1766 * Apply the delta at index n. If it fails, break
1767 * from the loop so we'll fall into the undo loop
1770 switch (msbp->msb_field) {
1771 #ifdef HAVE_PERCPU_SB
1772 case XFS_SBS_ICOUNT:
1774 case XFS_SBS_FDBLOCKS:
1775 if (!(mp->m_flags & XFS_MOUNT_NO_PERCPU_SB)) {
1776 spin_unlock(&mp->m_sb_lock);
1777 status = xfs_icsb_modify_counters(mp,
1779 msbp->msb_delta, rsvd);
1780 spin_lock(&mp->m_sb_lock);
1786 status = xfs_mod_incore_sb_unlocked(mp,
1788 msbp->msb_delta, rsvd);
1798 * If we didn't complete the loop above, then back out
1799 * any changes made to the superblock. If you add code
1800 * between the loop above and here, make sure that you
1801 * preserve the value of status. Loop back until
1802 * we step below the beginning of the array. Make sure
1803 * we don't touch anything back there.
1807 while (msbp >= msb) {
1808 switch (msbp->msb_field) {
1809 #ifdef HAVE_PERCPU_SB
1810 case XFS_SBS_ICOUNT:
1812 case XFS_SBS_FDBLOCKS:
1813 if (!(mp->m_flags & XFS_MOUNT_NO_PERCPU_SB)) {
1814 spin_unlock(&mp->m_sb_lock);
1815 status = xfs_icsb_modify_counters(mp,
1819 spin_lock(&mp->m_sb_lock);
1825 status = xfs_mod_incore_sb_unlocked(mp,
1831 ASSERT(status == 0);
1835 spin_unlock(&mp->m_sb_lock);
1840 * xfs_getsb() is called to obtain the buffer for the superblock.
1841 * The buffer is returned locked and read in from disk.
1842 * The buffer should be released with a call to xfs_brelse().
1844 * If the flags parameter is BUF_TRYLOCK, then we'll only return
1845 * the superblock buffer if it can be locked without sleeping.
1846 * If it can't then we'll return NULL.
1855 ASSERT(mp->m_sb_bp != NULL);
1857 if (flags & XFS_BUF_TRYLOCK) {
1858 if (!XFS_BUF_CPSEMA(bp)) {
1862 XFS_BUF_PSEMA(bp, PRIBIO);
1865 ASSERT(XFS_BUF_ISDONE(bp));
1870 * Used to free the superblock along various error paths.
1879 * Use xfs_getsb() so that the buffer will be locked
1880 * when we call xfs_buf_relse().
1882 bp = xfs_getsb(mp, 0);
1883 XFS_BUF_UNMANAGE(bp);
1889 * See if the UUID is unique among mounted XFS filesystems.
1890 * Mount fails if UUID is nil or a FS with the same UUID is already mounted.
1896 if (uuid_is_nil(&mp->m_sb.sb_uuid)) {
1898 "XFS: Filesystem %s has nil UUID - can't mount",
1902 if (!uuid_table_insert(&mp->m_sb.sb_uuid)) {
1904 "XFS: Filesystem %s has duplicate UUID - can't mount",
1912 * Used to log changes to the superblock unit and width fields which could
1913 * be altered by the mount options, as well as any potential sb_features2
1914 * fixup. Only the first superblock is updated.
1924 ASSERT(fields & (XFS_SB_UNIT | XFS_SB_WIDTH | XFS_SB_UUID |
1925 XFS_SB_FEATURES2 | XFS_SB_BAD_FEATURES2 |
1926 XFS_SB_VERSIONNUM));
1928 tp = xfs_trans_alloc(mp, XFS_TRANS_SB_UNIT);
1929 error = xfs_trans_reserve(tp, 0, mp->m_sb.sb_sectsize + 128, 0, 0,
1930 XFS_DEFAULT_LOG_COUNT);
1932 xfs_trans_cancel(tp, 0);
1935 xfs_mod_sb(tp, fields);
1936 error = xfs_trans_commit(tp, 0);
1941 #ifdef HAVE_PERCPU_SB
1943 * Per-cpu incore superblock counters
1945 * Simple concept, difficult implementation
1947 * Basically, replace the incore superblock counters with a distributed per cpu
1948 * counter for contended fields (e.g. free block count).
1950 * Difficulties arise in that the incore sb is used for ENOSPC checking, and
1951 * hence needs to be accurately read when we are running low on space. Hence
1952 * there is a method to enable and disable the per-cpu counters based on how
1953 * much "stuff" is available in them.
1955 * Basically, a counter is enabled if there is enough free resource to justify
1956 * running a per-cpu fast-path. If the per-cpu counter runs out (i.e. a local
1957 * ENOSPC), then we disable the counters to synchronise all callers and
1958 * re-distribute the available resources.
1960 * If, once we redistributed the available resources, we still get a failure,
1961 * we disable the per-cpu counter and go through the slow path.
1963 * The slow path is the current xfs_mod_incore_sb() function. This means that
1964 * when we disable a per-cpu counter, we need to drain it's resources back to
1965 * the global superblock. We do this after disabling the counter to prevent
1966 * more threads from queueing up on the counter.
1968 * Essentially, this means that we still need a lock in the fast path to enable
1969 * synchronisation between the global counters and the per-cpu counters. This
1970 * is not a problem because the lock will be local to a CPU almost all the time
1971 * and have little contention except when we get to ENOSPC conditions.
1973 * Basically, this lock becomes a barrier that enables us to lock out the fast
1974 * path while we do things like enabling and disabling counters and
1975 * synchronising the counters.
1979 * 1. m_sb_lock before picking up per-cpu locks
1980 * 2. per-cpu locks always picked up via for_each_online_cpu() order
1981 * 3. accurate counter sync requires m_sb_lock + per cpu locks
1982 * 4. modifying per-cpu counters requires holding per-cpu lock
1983 * 5. modifying global counters requires holding m_sb_lock
1984 * 6. enabling or disabling a counter requires holding the m_sb_lock
1985 * and _none_ of the per-cpu locks.
1987 * Disabled counters are only ever re-enabled by a balance operation
1988 * that results in more free resources per CPU than a given threshold.
1989 * To ensure counters don't remain disabled, they are rebalanced when
1990 * the global resource goes above a higher threshold (i.e. some hysteresis
1991 * is present to prevent thrashing).
1994 #ifdef CONFIG_HOTPLUG_CPU
1996 * hot-plug CPU notifier support.
1998 * We need a notifier per filesystem as we need to be able to identify
1999 * the filesystem to balance the counters out. This is achieved by
2000 * having a notifier block embedded in the xfs_mount_t and doing pointer
2001 * magic to get the mount pointer from the notifier block address.
2004 xfs_icsb_cpu_notify(
2005 struct notifier_block *nfb,
2006 unsigned long action,
2009 xfs_icsb_cnts_t *cntp;
2012 mp = (xfs_mount_t *)container_of(nfb, xfs_mount_t, m_icsb_notifier);
2013 cntp = (xfs_icsb_cnts_t *)
2014 per_cpu_ptr(mp->m_sb_cnts, (unsigned long)hcpu);
2016 case CPU_UP_PREPARE:
2017 case CPU_UP_PREPARE_FROZEN:
2018 /* Easy Case - initialize the area and locks, and
2019 * then rebalance when online does everything else for us. */
2020 memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
2023 case CPU_ONLINE_FROZEN:
2025 xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0);
2026 xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0);
2027 xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0);
2028 xfs_icsb_unlock(mp);
2031 case CPU_DEAD_FROZEN:
2032 /* Disable all the counters, then fold the dead cpu's
2033 * count into the total on the global superblock and
2034 * re-enable the counters. */
2036 spin_lock(&mp->m_sb_lock);
2037 xfs_icsb_disable_counter(mp, XFS_SBS_ICOUNT);
2038 xfs_icsb_disable_counter(mp, XFS_SBS_IFREE);
2039 xfs_icsb_disable_counter(mp, XFS_SBS_FDBLOCKS);
2041 mp->m_sb.sb_icount += cntp->icsb_icount;
2042 mp->m_sb.sb_ifree += cntp->icsb_ifree;
2043 mp->m_sb.sb_fdblocks += cntp->icsb_fdblocks;
2045 memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
2047 xfs_icsb_balance_counter_locked(mp, XFS_SBS_ICOUNT, 0);
2048 xfs_icsb_balance_counter_locked(mp, XFS_SBS_IFREE, 0);
2049 xfs_icsb_balance_counter_locked(mp, XFS_SBS_FDBLOCKS, 0);
2050 spin_unlock(&mp->m_sb_lock);
2051 xfs_icsb_unlock(mp);
2057 #endif /* CONFIG_HOTPLUG_CPU */
2060 xfs_icsb_init_counters(
2063 xfs_icsb_cnts_t *cntp;
2066 mp->m_sb_cnts = alloc_percpu(xfs_icsb_cnts_t);
2067 if (mp->m_sb_cnts == NULL)
2070 #ifdef CONFIG_HOTPLUG_CPU
2071 mp->m_icsb_notifier.notifier_call = xfs_icsb_cpu_notify;
2072 mp->m_icsb_notifier.priority = 0;
2073 register_hotcpu_notifier(&mp->m_icsb_notifier);
2074 #endif /* CONFIG_HOTPLUG_CPU */
2076 for_each_online_cpu(i) {
2077 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
2078 memset(cntp, 0, sizeof(xfs_icsb_cnts_t));
2081 mutex_init(&mp->m_icsb_mutex);
2084 * start with all counters disabled so that the
2085 * initial balance kicks us off correctly
2087 mp->m_icsb_counters = -1;
2092 xfs_icsb_reinit_counters(
2097 * start with all counters disabled so that the
2098 * initial balance kicks us off correctly
2100 mp->m_icsb_counters = -1;
2101 xfs_icsb_balance_counter(mp, XFS_SBS_ICOUNT, 0);
2102 xfs_icsb_balance_counter(mp, XFS_SBS_IFREE, 0);
2103 xfs_icsb_balance_counter(mp, XFS_SBS_FDBLOCKS, 0);
2104 xfs_icsb_unlock(mp);
2108 xfs_icsb_destroy_counters(
2111 if (mp->m_sb_cnts) {
2112 unregister_hotcpu_notifier(&mp->m_icsb_notifier);
2113 free_percpu(mp->m_sb_cnts);
2115 mutex_destroy(&mp->m_icsb_mutex);
2120 xfs_icsb_cnts_t *icsbp)
2122 while (test_and_set_bit(XFS_ICSB_FLAG_LOCK, &icsbp->icsb_flags)) {
2128 xfs_icsb_unlock_cntr(
2129 xfs_icsb_cnts_t *icsbp)
2131 clear_bit(XFS_ICSB_FLAG_LOCK, &icsbp->icsb_flags);
2136 xfs_icsb_lock_all_counters(
2139 xfs_icsb_cnts_t *cntp;
2142 for_each_online_cpu(i) {
2143 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
2144 xfs_icsb_lock_cntr(cntp);
2149 xfs_icsb_unlock_all_counters(
2152 xfs_icsb_cnts_t *cntp;
2155 for_each_online_cpu(i) {
2156 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
2157 xfs_icsb_unlock_cntr(cntp);
2164 xfs_icsb_cnts_t *cnt,
2167 xfs_icsb_cnts_t *cntp;
2170 memset(cnt, 0, sizeof(xfs_icsb_cnts_t));
2172 if (!(flags & XFS_ICSB_LAZY_COUNT))
2173 xfs_icsb_lock_all_counters(mp);
2175 for_each_online_cpu(i) {
2176 cntp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, i);
2177 cnt->icsb_icount += cntp->icsb_icount;
2178 cnt->icsb_ifree += cntp->icsb_ifree;
2179 cnt->icsb_fdblocks += cntp->icsb_fdblocks;
2182 if (!(flags & XFS_ICSB_LAZY_COUNT))
2183 xfs_icsb_unlock_all_counters(mp);
2187 xfs_icsb_counter_disabled(
2189 xfs_sb_field_t field)
2191 ASSERT((field >= XFS_SBS_ICOUNT) && (field <= XFS_SBS_FDBLOCKS));
2192 return test_bit(field, &mp->m_icsb_counters);
2196 xfs_icsb_disable_counter(
2198 xfs_sb_field_t field)
2200 xfs_icsb_cnts_t cnt;
2202 ASSERT((field >= XFS_SBS_ICOUNT) && (field <= XFS_SBS_FDBLOCKS));
2205 * If we are already disabled, then there is nothing to do
2206 * here. We check before locking all the counters to avoid
2207 * the expensive lock operation when being called in the
2208 * slow path and the counter is already disabled. This is
2209 * safe because the only time we set or clear this state is under
2212 if (xfs_icsb_counter_disabled(mp, field))
2215 xfs_icsb_lock_all_counters(mp);
2216 if (!test_and_set_bit(field, &mp->m_icsb_counters)) {
2217 /* drain back to superblock */
2219 xfs_icsb_count(mp, &cnt, XFS_ICSB_LAZY_COUNT);
2221 case XFS_SBS_ICOUNT:
2222 mp->m_sb.sb_icount = cnt.icsb_icount;
2225 mp->m_sb.sb_ifree = cnt.icsb_ifree;
2227 case XFS_SBS_FDBLOCKS:
2228 mp->m_sb.sb_fdblocks = cnt.icsb_fdblocks;
2235 xfs_icsb_unlock_all_counters(mp);
2239 xfs_icsb_enable_counter(
2241 xfs_sb_field_t field,
2245 xfs_icsb_cnts_t *cntp;
2248 ASSERT((field >= XFS_SBS_ICOUNT) && (field <= XFS_SBS_FDBLOCKS));
2250 xfs_icsb_lock_all_counters(mp);
2251 for_each_online_cpu(i) {
2252 cntp = per_cpu_ptr(mp->m_sb_cnts, i);
2254 case XFS_SBS_ICOUNT:
2255 cntp->icsb_icount = count + resid;
2258 cntp->icsb_ifree = count + resid;
2260 case XFS_SBS_FDBLOCKS:
2261 cntp->icsb_fdblocks = count + resid;
2269 clear_bit(field, &mp->m_icsb_counters);
2270 xfs_icsb_unlock_all_counters(mp);
2274 xfs_icsb_sync_counters_locked(
2278 xfs_icsb_cnts_t cnt;
2280 xfs_icsb_count(mp, &cnt, flags);
2282 if (!xfs_icsb_counter_disabled(mp, XFS_SBS_ICOUNT))
2283 mp->m_sb.sb_icount = cnt.icsb_icount;
2284 if (!xfs_icsb_counter_disabled(mp, XFS_SBS_IFREE))
2285 mp->m_sb.sb_ifree = cnt.icsb_ifree;
2286 if (!xfs_icsb_counter_disabled(mp, XFS_SBS_FDBLOCKS))
2287 mp->m_sb.sb_fdblocks = cnt.icsb_fdblocks;
2291 * Accurate update of per-cpu counters to incore superblock
2294 xfs_icsb_sync_counters(
2298 spin_lock(&mp->m_sb_lock);
2299 xfs_icsb_sync_counters_locked(mp, flags);
2300 spin_unlock(&mp->m_sb_lock);
2304 * Balance and enable/disable counters as necessary.
2306 * Thresholds for re-enabling counters are somewhat magic. inode counts are
2307 * chosen to be the same number as single on disk allocation chunk per CPU, and
2308 * free blocks is something far enough zero that we aren't going thrash when we
2309 * get near ENOSPC. We also need to supply a minimum we require per cpu to
2310 * prevent looping endlessly when xfs_alloc_space asks for more than will
2311 * be distributed to a single CPU but each CPU has enough blocks to be
2314 * Note that we can be called when counters are already disabled.
2315 * xfs_icsb_disable_counter() optimises the counter locking in this case to
2316 * prevent locking every per-cpu counter needlessly.
2319 #define XFS_ICSB_INO_CNTR_REENABLE (uint64_t)64
2320 #define XFS_ICSB_FDBLK_CNTR_REENABLE(mp) \
2321 (uint64_t)(512 + XFS_ALLOC_SET_ASIDE(mp))
2323 xfs_icsb_balance_counter_locked(
2325 xfs_sb_field_t field,
2328 uint64_t count, resid;
2329 int weight = num_online_cpus();
2330 uint64_t min = (uint64_t)min_per_cpu;
2332 /* disable counter and sync counter */
2333 xfs_icsb_disable_counter(mp, field);
2335 /* update counters - first CPU gets residual*/
2337 case XFS_SBS_ICOUNT:
2338 count = mp->m_sb.sb_icount;
2339 resid = do_div(count, weight);
2340 if (count < max(min, XFS_ICSB_INO_CNTR_REENABLE))
2344 count = mp->m_sb.sb_ifree;
2345 resid = do_div(count, weight);
2346 if (count < max(min, XFS_ICSB_INO_CNTR_REENABLE))
2349 case XFS_SBS_FDBLOCKS:
2350 count = mp->m_sb.sb_fdblocks;
2351 resid = do_div(count, weight);
2352 if (count < max(min, XFS_ICSB_FDBLK_CNTR_REENABLE(mp)))
2357 count = resid = 0; /* quiet, gcc */
2361 xfs_icsb_enable_counter(mp, field, count, resid);
2365 xfs_icsb_balance_counter(
2367 xfs_sb_field_t fields,
2370 spin_lock(&mp->m_sb_lock);
2371 xfs_icsb_balance_counter_locked(mp, fields, min_per_cpu);
2372 spin_unlock(&mp->m_sb_lock);
2376 xfs_icsb_modify_counters(
2378 xfs_sb_field_t field,
2382 xfs_icsb_cnts_t *icsbp;
2383 long long lcounter; /* long counter for 64 bit fields */
2389 icsbp = (xfs_icsb_cnts_t *)per_cpu_ptr(mp->m_sb_cnts, cpu);
2392 * if the counter is disabled, go to slow path
2394 if (unlikely(xfs_icsb_counter_disabled(mp, field)))
2396 xfs_icsb_lock_cntr(icsbp);
2397 if (unlikely(xfs_icsb_counter_disabled(mp, field))) {
2398 xfs_icsb_unlock_cntr(icsbp);
2403 case XFS_SBS_ICOUNT:
2404 lcounter = icsbp->icsb_icount;
2406 if (unlikely(lcounter < 0))
2407 goto balance_counter;
2408 icsbp->icsb_icount = lcounter;
2412 lcounter = icsbp->icsb_ifree;
2414 if (unlikely(lcounter < 0))
2415 goto balance_counter;
2416 icsbp->icsb_ifree = lcounter;
2419 case XFS_SBS_FDBLOCKS:
2420 BUG_ON((mp->m_resblks - mp->m_resblks_avail) != 0);
2422 lcounter = icsbp->icsb_fdblocks - XFS_ALLOC_SET_ASIDE(mp);
2424 if (unlikely(lcounter < 0))
2425 goto balance_counter;
2426 icsbp->icsb_fdblocks = lcounter + XFS_ALLOC_SET_ASIDE(mp);
2432 xfs_icsb_unlock_cntr(icsbp);
2440 * serialise with a mutex so we don't burn lots of cpu on
2441 * the superblock lock. We still need to hold the superblock
2442 * lock, however, when we modify the global structures.
2447 * Now running atomically.
2449 * If the counter is enabled, someone has beaten us to rebalancing.
2450 * Drop the lock and try again in the fast path....
2452 if (!(xfs_icsb_counter_disabled(mp, field))) {
2453 xfs_icsb_unlock(mp);
2458 * The counter is currently disabled. Because we are
2459 * running atomically here, we know a rebalance cannot
2460 * be in progress. Hence we can go straight to operating
2461 * on the global superblock. We do not call xfs_mod_incore_sb()
2462 * here even though we need to get the m_sb_lock. Doing so
2463 * will cause us to re-enter this function and deadlock.
2464 * Hence we get the m_sb_lock ourselves and then call
2465 * xfs_mod_incore_sb_unlocked() as the unlocked path operates
2466 * directly on the global counters.
2468 spin_lock(&mp->m_sb_lock);
2469 ret = xfs_mod_incore_sb_unlocked(mp, field, delta, rsvd);
2470 spin_unlock(&mp->m_sb_lock);
2473 * Now that we've modified the global superblock, we
2474 * may be able to re-enable the distributed counters
2475 * (e.g. lots of space just got freed). After that
2479 xfs_icsb_balance_counter(mp, field, 0);
2480 xfs_icsb_unlock(mp);
2484 xfs_icsb_unlock_cntr(icsbp);
2488 * We may have multiple threads here if multiple per-cpu
2489 * counters run dry at the same time. This will mean we can
2490 * do more balances than strictly necessary but it is not
2491 * the common slowpath case.
2496 * running atomically.
2498 * This will leave the counter in the correct state for future
2499 * accesses. After the rebalance, we simply try again and our retry
2500 * will either succeed through the fast path or slow path without
2501 * another balance operation being required.
2503 xfs_icsb_balance_counter(mp, field, delta);
2504 xfs_icsb_unlock(mp);