2 * Copyright (c) 2007-2008 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@backplane.com>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * 3. Neither the name of The DragonFly Project nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific, prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * $DragonFly: src/sys/vfs/hammer/hammer_ondisk.c,v 1.76 2008/08/29 20:19:08 dillon Exp $
37 * Manage HAMMER's on-disk structures. These routines are primarily
38 * responsible for interfacing with the kernel's I/O subsystem and for
39 * managing in-memory structures.
43 #include <sys/fcntl.h>
44 #include <sys/nlookup.h>
48 static void hammer_free_volume(hammer_volume_t volume
);
49 static int hammer_load_volume(hammer_volume_t volume
);
50 static int hammer_load_buffer(hammer_buffer_t buffer
, int isnew
);
51 static int hammer_load_node(hammer_node_t node
, int isnew
);
54 hammer_vol_rb_compare(hammer_volume_t vol1
, hammer_volume_t vol2
)
56 if (vol1
->vol_no
< vol2
->vol_no
)
58 if (vol1
->vol_no
> vol2
->vol_no
)
64 hammer_buf_rb_compare(hammer_buffer_t buf1
, hammer_buffer_t buf2
)
66 if (buf1
->zoneX_offset
< buf2
->zoneX_offset
)
68 if (buf1
->zoneX_offset
> buf2
->zoneX_offset
)
74 hammer_nod_rb_compare(hammer_node_t node1
, hammer_node_t node2
)
76 if (node1
->node_offset
< node2
->node_offset
)
78 if (node1
->node_offset
> node2
->node_offset
)
83 RB_GENERATE2(hammer_vol_rb_tree
, hammer_volume
, rb_node
,
84 hammer_vol_rb_compare
, int32_t, vol_no
);
85 RB_GENERATE2(hammer_buf_rb_tree
, hammer_buffer
, rb_node
,
86 hammer_buf_rb_compare
, hammer_off_t
, zoneX_offset
);
87 RB_GENERATE2(hammer_nod_rb_tree
, hammer_node
, rb_node
,
88 hammer_nod_rb_compare
, hammer_off_t
, node_offset
);
90 /************************************************************************
92 ************************************************************************
94 * Load a HAMMER volume by name. Returns 0 on success or a positive error
95 * code on failure. Volumes must be loaded at mount time, get_volume() will
96 * not load a new volume.
98 * Calls made to hammer_load_volume() or single-threaded
101 hammer_install_volume(struct hammer_mount
*hmp
, const char *volname
,
105 hammer_volume_t volume
;
106 struct hammer_volume_ondisk
*ondisk
;
107 struct nlookupdata nd
;
108 struct buf
*bp
= NULL
;
114 ronly
= ((mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
117 * Allocate a volume structure
119 ++hammer_count_volumes
;
120 volume
= kmalloc(sizeof(*volume
), M_HAMMER
, M_WAITOK
|M_ZERO
);
121 volume
->vol_name
= kstrdup(volname
, M_HAMMER
);
122 volume
->io
.hmp
= hmp
; /* bootstrap */
123 hammer_io_init(&volume
->io
, volume
, HAMMER_STRUCTURE_VOLUME
);
124 volume
->io
.offset
= 0LL;
125 volume
->io
.bytes
= HAMMER_BUFSIZE
;
128 * Get the device vnode
131 error
= nlookup_init(&nd
, volume
->vol_name
, UIO_SYSSPACE
, NLC_FOLLOW
);
133 error
= nlookup(&nd
);
135 error
= cache_vref(&nd
.nl_nch
, nd
.nl_cred
, &volume
->devvp
);
139 volume
->devvp
= devvp
;
143 if (vn_isdisk(volume
->devvp
, &error
)) {
144 error
= vfs_mountedon(volume
->devvp
);
148 count_udev(volume
->devvp
->v_umajor
, volume
->devvp
->v_uminor
) > 0) {
152 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
153 error
= vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
155 error
= VOP_OPEN(volume
->devvp
,
156 (ronly
? FREAD
: FREAD
|FWRITE
),
159 vn_unlock(volume
->devvp
);
162 hammer_free_volume(volume
);
165 volume
->devvp
->v_rdev
->si_mountpoint
= mp
;
169 * Extract the volume number from the volume header and do various
172 error
= bread(volume
->devvp
, 0LL, HAMMER_BUFSIZE
, &bp
);
175 ondisk
= (void *)bp
->b_data
;
176 if (ondisk
->vol_signature
!= HAMMER_FSBUF_VOLUME
) {
177 kprintf("hammer_mount: volume %s has an invalid header\n",
182 volume
->vol_no
= ondisk
->vol_no
;
183 volume
->buffer_base
= ondisk
->vol_buf_beg
;
184 volume
->vol_flags
= ondisk
->vol_flags
;
185 volume
->nblocks
= ondisk
->vol_nblocks
;
186 volume
->maxbuf_off
= HAMMER_ENCODE_RAW_BUFFER(volume
->vol_no
,
187 ondisk
->vol_buf_end
- ondisk
->vol_buf_beg
);
188 volume
->maxraw_off
= ondisk
->vol_buf_end
;
190 if (RB_EMPTY(&hmp
->rb_vols_root
)) {
191 hmp
->fsid
= ondisk
->vol_fsid
;
192 } else if (bcmp(&hmp
->fsid
, &ondisk
->vol_fsid
, sizeof(uuid_t
))) {
193 kprintf("hammer_mount: volume %s's fsid does not match "
194 "other volumes\n", volume
->vol_name
);
200 * Insert the volume structure into the red-black tree.
202 if (RB_INSERT(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
)) {
203 kprintf("hammer_mount: volume %s has a duplicate vol_no %d\n",
204 volume
->vol_name
, volume
->vol_no
);
209 * Set the root volume . HAMMER special cases rootvol the structure.
210 * We do not hold a ref because this would prevent related I/O
211 * from being flushed.
213 if (error
== 0 && ondisk
->vol_rootvol
== ondisk
->vol_no
) {
214 hmp
->rootvol
= volume
;
215 hmp
->nvolumes
= ondisk
->vol_count
;
220 hmp
->mp
->mnt_stat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
221 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
222 hmp
->mp
->mnt_vstat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
223 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
229 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/
231 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
232 VOP_CLOSE(volume
->devvp
, ronly
? FREAD
: FREAD
|FWRITE
);
233 hammer_free_volume(volume
);
239 * This is called for each volume when updating the mount point from
240 * read-write to read-only or vise-versa.
243 hammer_adjust_volume_mode(hammer_volume_t volume
, void *data __unused
)
246 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
247 if (volume
->io
.hmp
->ronly
) {
248 /* do not call vinvalbuf */
249 VOP_OPEN(volume
->devvp
, FREAD
, FSCRED
, NULL
);
250 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
252 /* do not call vinvalbuf */
253 VOP_OPEN(volume
->devvp
, FREAD
|FWRITE
, FSCRED
, NULL
);
254 VOP_CLOSE(volume
->devvp
, FREAD
);
256 vn_unlock(volume
->devvp
);
262 * Unload and free a HAMMER volume. Must return >= 0 to continue scan
263 * so returns -1 on failure.
266 hammer_unload_volume(hammer_volume_t volume
, void *data __unused
)
268 struct hammer_mount
*hmp
= volume
->io
.hmp
;
269 int ronly
= ((hmp
->mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
273 * Clean up the root volume pointer, which is held unlocked in hmp.
275 if (hmp
->rootvol
== volume
)
279 * We must not flush a dirty buffer to disk on umount. It should
280 * have already been dealt with by the flusher, or we may be in
281 * catastrophic failure.
283 hammer_io_clear_modify(&volume
->io
, 1);
284 volume
->io
.waitdep
= 1;
285 bp
= hammer_io_release(&volume
->io
, 1);
288 * Clean up the persistent ref ioerror might have on the volume
290 if (volume
->io
.ioerror
) {
291 volume
->io
.ioerror
= 0;
292 hammer_unref(&volume
->io
.lock
);
296 * There should be no references on the volume, no clusters, and
299 KKASSERT(volume
->io
.lock
.refs
== 0);
303 volume
->ondisk
= NULL
;
305 if (volume
->devvp
->v_rdev
&&
306 volume
->devvp
->v_rdev
->si_mountpoint
== hmp
->mp
308 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
312 * Make sure we don't sync anything to disk if we
313 * are in read-only mode (1) or critically-errored
314 * (2). Note that there may be dirty buffers in
315 * normal read-only mode from crash recovery.
317 vinvalbuf(volume
->devvp
, 0, 0, 0);
318 VOP_CLOSE(volume
->devvp
, FREAD
);
321 * Normal termination, save any dirty buffers
322 * (XXX there really shouldn't be any).
324 vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
325 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
330 * Destroy the structure
332 RB_REMOVE(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
);
333 hammer_free_volume(volume
);
339 hammer_free_volume(hammer_volume_t volume
)
341 if (volume
->vol_name
) {
342 kfree(volume
->vol_name
, M_HAMMER
);
343 volume
->vol_name
= NULL
;
346 vrele(volume
->devvp
);
347 volume
->devvp
= NULL
;
349 --hammer_count_volumes
;
350 kfree(volume
, M_HAMMER
);
354 * Get a HAMMER volume. The volume must already exist.
357 hammer_get_volume(struct hammer_mount
*hmp
, int32_t vol_no
, int *errorp
)
359 struct hammer_volume
*volume
;
362 * Locate the volume structure
364 volume
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, vol_no
);
365 if (volume
== NULL
) {
369 hammer_ref(&volume
->io
.lock
);
372 * Deal with on-disk info
374 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
375 *errorp
= hammer_load_volume(volume
);
377 hammer_rel_volume(volume
, 1);
387 hammer_ref_volume(hammer_volume_t volume
)
391 hammer_ref(&volume
->io
.lock
);
394 * Deal with on-disk info
396 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
397 error
= hammer_load_volume(volume
);
399 hammer_rel_volume(volume
, 1);
407 hammer_get_root_volume(struct hammer_mount
*hmp
, int *errorp
)
409 hammer_volume_t volume
;
411 volume
= hmp
->rootvol
;
412 KKASSERT(volume
!= NULL
);
413 hammer_ref(&volume
->io
.lock
);
416 * Deal with on-disk info
418 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
419 *errorp
= hammer_load_volume(volume
);
421 hammer_rel_volume(volume
, 1);
431 * Load a volume's on-disk information. The volume must be referenced and
432 * not locked. We temporarily acquire an exclusive lock to interlock
433 * against releases or multiple get's.
436 hammer_load_volume(hammer_volume_t volume
)
440 ++volume
->io
.loading
;
441 hammer_lock_ex(&volume
->io
.lock
);
443 if (volume
->ondisk
== NULL
) {
444 error
= hammer_io_read(volume
->devvp
, &volume
->io
,
447 volume
->ondisk
= (void *)volume
->io
.bp
->b_data
;
451 --volume
->io
.loading
;
452 hammer_unlock(&volume
->io
.lock
);
457 * Release a volume. Call hammer_io_release on the last reference. We have
458 * to acquire an exclusive lock to interlock against volume->ondisk tests
459 * in hammer_load_volume(), and hammer_io_release() also expects an exclusive
462 * Volumes are not unloaded from memory during normal operation.
465 hammer_rel_volume(hammer_volume_t volume
, int flush
)
467 struct buf
*bp
= NULL
;
470 if (volume
->io
.lock
.refs
== 1) {
471 ++volume
->io
.loading
;
472 hammer_lock_ex(&volume
->io
.lock
);
473 if (volume
->io
.lock
.refs
== 1) {
474 volume
->ondisk
= NULL
;
475 bp
= hammer_io_release(&volume
->io
, flush
);
477 --volume
->io
.loading
;
478 hammer_unlock(&volume
->io
.lock
);
480 hammer_unref(&volume
->io
.lock
);
487 hammer_mountcheck_volumes(struct hammer_mount
*hmp
)
492 for (i
= 0; i
< hmp
->nvolumes
; ++i
) {
493 vol
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, i
);
500 /************************************************************************
502 ************************************************************************
504 * Manage buffers. Currently all blockmap-backed zones are translated
505 * to zone-2 buffer offsets.
508 hammer_get_buffer(hammer_mount_t hmp
, hammer_off_t buf_offset
,
509 int bytes
, int isnew
, int *errorp
)
511 hammer_buffer_t buffer
;
512 hammer_volume_t volume
;
513 hammer_off_t zone2_offset
;
514 hammer_io_type_t iotype
;
518 buf_offset
&= ~HAMMER_BUFMASK64
;
521 * Shortcut if the buffer is already cached
523 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buf_offset
);
525 if (buffer
->io
.lock
.refs
== 0)
526 ++hammer_count_refedbufs
;
527 hammer_ref(&buffer
->io
.lock
);
530 * Once refed the ondisk field will not be cleared by
533 if (buffer
->ondisk
&& buffer
->io
.loading
== 0) {
539 * The buffer is no longer loose if it has a ref, and
540 * cannot become loose once it gains a ref. Loose
541 * buffers will never be in a modified state. This should
542 * only occur on the 0->1 transition of refs.
544 * lose_list can be modified via a biodone() interrupt.
546 if (buffer
->io
.mod_list
== &hmp
->lose_list
) {
547 crit_enter(); /* biodone race against list */
548 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
,
551 buffer
->io
.mod_list
= NULL
;
552 KKASSERT(buffer
->io
.modified
== 0);
558 * What is the buffer class?
560 zone
= HAMMER_ZONE_DECODE(buf_offset
);
563 case HAMMER_ZONE_LARGE_DATA_INDEX
:
564 case HAMMER_ZONE_SMALL_DATA_INDEX
:
565 iotype
= HAMMER_STRUCTURE_DATA_BUFFER
;
567 case HAMMER_ZONE_UNDO_INDEX
:
568 iotype
= HAMMER_STRUCTURE_UNDO_BUFFER
;
570 case HAMMER_ZONE_META_INDEX
:
573 * NOTE: inode data and directory entries are placed in this
574 * zone. inode atime/mtime is updated in-place and thus
575 * buffers containing inodes must be synchronized as
576 * meta-buffers, same as buffers containing B-Tree info.
578 iotype
= HAMMER_STRUCTURE_META_BUFFER
;
583 * Handle blockmap offset translations
585 if (zone
>= HAMMER_ZONE_BTREE_INDEX
) {
586 zone2_offset
= hammer_blockmap_lookup(hmp
, buf_offset
, errorp
);
587 } else if (zone
== HAMMER_ZONE_UNDO_INDEX
) {
588 zone2_offset
= hammer_undo_lookup(hmp
, buf_offset
, errorp
);
590 KKASSERT(zone
== HAMMER_ZONE_RAW_BUFFER_INDEX
);
591 zone2_offset
= buf_offset
;
598 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset
601 KKASSERT((zone2_offset
& HAMMER_OFF_ZONE_MASK
) ==
602 HAMMER_ZONE_RAW_BUFFER
);
603 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
604 volume
= hammer_get_volume(hmp
, vol_no
, errorp
);
608 KKASSERT(zone2_offset
< volume
->maxbuf_off
);
611 * Allocate a new buffer structure. We will check for races later.
613 ++hammer_count_buffers
;
614 buffer
= kmalloc(sizeof(*buffer
), M_HAMMER
,
615 M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
616 buffer
->zone2_offset
= zone2_offset
;
617 buffer
->zoneX_offset
= buf_offset
;
619 hammer_io_init(&buffer
->io
, volume
, iotype
);
620 buffer
->io
.offset
= volume
->ondisk
->vol_buf_beg
+
621 (zone2_offset
& HAMMER_OFF_SHORT_MASK
);
622 buffer
->io
.bytes
= bytes
;
623 TAILQ_INIT(&buffer
->clist
);
624 hammer_ref(&buffer
->io
.lock
);
627 * Insert the buffer into the RB tree and handle late collisions.
629 if (RB_INSERT(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buffer
)) {
630 hammer_unref(&buffer
->io
.lock
);
631 --hammer_count_buffers
;
632 kfree(buffer
, M_HAMMER
);
635 ++hammer_count_refedbufs
;
639 * Deal with on-disk info and loading races.
641 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
642 *errorp
= hammer_load_buffer(buffer
, isnew
);
644 hammer_rel_buffer(buffer
, 1);
654 * This is used by the direct-read code to deal with large-data buffers
655 * created by the reblocker and mirror-write code. The direct-read code
656 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write-
657 * running hammer buffers must be fully synced to disk before we can issue
660 * This code path is not considered critical as only the rebocker and
661 * mirror-write code will create large-data buffers via the HAMMER buffer
662 * subsystem. They do that because they operate at the B-Tree level and
663 * do not access the vnode/inode structures.
666 hammer_sync_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
, int bytes
)
668 hammer_buffer_t buffer
;
671 KKASSERT((base_offset
& HAMMER_OFF_ZONE_MASK
) ==
672 HAMMER_ZONE_LARGE_DATA
);
675 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
677 if (buffer
&& (buffer
->io
.modified
|| buffer
->io
.running
)) {
678 error
= hammer_ref_buffer(buffer
);
680 hammer_io_wait(&buffer
->io
);
681 if (buffer
->io
.modified
) {
682 hammer_io_write_interlock(&buffer
->io
);
683 hammer_io_flush(&buffer
->io
);
684 hammer_io_done_interlock(&buffer
->io
);
685 hammer_io_wait(&buffer
->io
);
687 hammer_rel_buffer(buffer
, 0);
690 base_offset
+= HAMMER_BUFSIZE
;
691 bytes
-= HAMMER_BUFSIZE
;
696 * Destroy all buffers covering the specified zoneX offset range. This
697 * is called when the related blockmap layer2 entry is freed or when
698 * a direct write bypasses our buffer/buffer-cache subsystem.
700 * The buffers may be referenced by the caller itself. Setting reclaim
701 * will cause the buffer to be destroyed when it's ref count reaches zero.
704 hammer_del_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
,
705 hammer_off_t zone2_offset
, int bytes
)
707 hammer_buffer_t buffer
;
708 hammer_volume_t volume
;
712 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
713 volume
= hammer_get_volume(hmp
, vol_no
, &error
);
714 KKASSERT(error
== 0);
717 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
720 error
= hammer_ref_buffer(buffer
);
722 KKASSERT(buffer
->zone2_offset
== zone2_offset
);
723 hammer_io_clear_modify(&buffer
->io
, 1);
724 buffer
->io
.reclaim
= 1;
725 buffer
->io
.waitdep
= 1;
726 KKASSERT(buffer
->io
.volume
== volume
);
727 hammer_rel_buffer(buffer
, 0);
730 hammer_io_inval(volume
, zone2_offset
);
732 base_offset
+= HAMMER_BUFSIZE
;
733 zone2_offset
+= HAMMER_BUFSIZE
;
734 bytes
-= HAMMER_BUFSIZE
;
736 hammer_rel_volume(volume
, 0);
740 hammer_load_buffer(hammer_buffer_t buffer
, int isnew
)
742 hammer_volume_t volume
;
746 * Load the buffer's on-disk info
748 volume
= buffer
->io
.volume
;
749 ++buffer
->io
.loading
;
750 hammer_lock_ex(&buffer
->io
.lock
);
752 if (hammer_debug_io
& 0x0001) {
753 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n",
754 buffer
->zoneX_offset
, buffer
->zone2_offset
, isnew
,
758 if (buffer
->ondisk
== NULL
) {
760 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
762 error
= hammer_io_read(volume
->devvp
, &buffer
->io
,
766 buffer
->ondisk
= (void *)buffer
->io
.bp
->b_data
;
768 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
772 --buffer
->io
.loading
;
773 hammer_unlock(&buffer
->io
.lock
);
778 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue.
779 * This routine is only called during unmount.
782 hammer_unload_buffer(hammer_buffer_t buffer
, void *data __unused
)
785 * Clean up the persistent ref ioerror might have on the buffer
786 * and acquire a ref (steal ioerror's if we can).
788 if (buffer
->io
.ioerror
) {
789 buffer
->io
.ioerror
= 0;
791 if (buffer
->io
.lock
.refs
== 0)
792 ++hammer_count_refedbufs
;
793 hammer_ref(&buffer
->io
.lock
);
797 * We must not flush a dirty buffer to disk on umount. It should
798 * have already been dealt with by the flusher, or we may be in
799 * catastrophic failure.
801 hammer_io_clear_modify(&buffer
->io
, 1);
802 hammer_flush_buffer_nodes(buffer
);
803 KKASSERT(buffer
->io
.lock
.refs
== 1);
804 hammer_rel_buffer(buffer
, 2);
809 * Reference a buffer that is either already referenced or via a specially
810 * handled pointer (aka cursor->buffer).
813 hammer_ref_buffer(hammer_buffer_t buffer
)
817 if (buffer
->io
.lock
.refs
== 0)
818 ++hammer_count_refedbufs
;
819 hammer_ref(&buffer
->io
.lock
);
822 * At this point a biodone() will not touch the buffer other then
823 * incidental bits. However, lose_list can be modified via
824 * a biodone() interrupt.
828 if (buffer
->io
.mod_list
== &buffer
->io
.hmp
->lose_list
) {
830 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
, mod_entry
);
831 buffer
->io
.mod_list
= NULL
;
835 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
836 error
= hammer_load_buffer(buffer
, 0);
838 hammer_rel_buffer(buffer
, 1);
840 * NOTE: buffer pointer can become stale after
851 * Release a buffer. We have to deal with several places where
852 * another thread can ref the buffer.
854 * Only destroy the structure itself if the related buffer cache buffer
855 * was disassociated from it. This ties the management of the structure
856 * to the buffer cache subsystem. buffer->ondisk determines whether the
857 * embedded io is referenced or not.
860 hammer_rel_buffer(hammer_buffer_t buffer
, int flush
)
862 hammer_volume_t volume
;
863 struct buf
*bp
= NULL
;
867 if (buffer
->io
.lock
.refs
== 1) {
868 ++buffer
->io
.loading
; /* force interlock check */
869 hammer_lock_ex(&buffer
->io
.lock
);
870 if (buffer
->io
.lock
.refs
== 1) {
871 bp
= hammer_io_release(&buffer
->io
, flush
);
873 if (buffer
->io
.lock
.refs
== 1)
874 --hammer_count_refedbufs
;
876 if (buffer
->io
.bp
== NULL
&&
877 buffer
->io
.lock
.refs
== 1) {
881 * NOTE: It is impossible for any associated
882 * B-Tree nodes to have refs if the buffer
883 * has no additional refs.
885 RB_REMOVE(hammer_buf_rb_tree
,
886 &buffer
->io
.hmp
->rb_bufs_root
,
888 volume
= buffer
->io
.volume
;
889 buffer
->io
.volume
= NULL
; /* sanity */
890 hammer_rel_volume(volume
, 0);
891 hammer_io_clear_modlist(&buffer
->io
);
892 hammer_flush_buffer_nodes(buffer
);
893 KKASSERT(TAILQ_EMPTY(&buffer
->clist
));
897 --buffer
->io
.loading
;
898 hammer_unlock(&buffer
->io
.lock
);
900 hammer_unref(&buffer
->io
.lock
);
905 --hammer_count_buffers
;
906 kfree(buffer
, M_HAMMER
);
911 * Access the filesystem buffer containing the specified hammer offset.
912 * buf_offset is a conglomeration of the volume number and vol_buf_beg
913 * relative buffer offset. It must also have bit 55 set to be valid.
914 * (see hammer_off_t in hammer_disk.h).
916 * Any prior buffer in *bufferp will be released and replaced by the
921 _hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
922 int *errorp
, struct hammer_buffer
**bufferp
)
924 hammer_buffer_t buffer
;
925 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
927 buf_offset
&= ~HAMMER_BUFMASK64
;
928 KKASSERT((buf_offset
& HAMMER_OFF_ZONE_MASK
) != 0);
931 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
932 buffer
->zoneX_offset
!= buf_offset
)) {
934 hammer_rel_buffer(buffer
, 0);
935 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 0, errorp
);
942 * Return a pointer to the buffer data.
947 return((char *)buffer
->ondisk
+ xoff
);
951 hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
,
952 int *errorp
, struct hammer_buffer
**bufferp
)
954 return(_hammer_bread(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
958 hammer_bread_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
959 int *errorp
, struct hammer_buffer
**bufferp
)
961 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
962 return(_hammer_bread(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
966 * Access the filesystem buffer containing the specified hammer offset.
967 * No disk read operation occurs. The result buffer may contain garbage.
969 * Any prior buffer in *bufferp will be released and replaced by the
972 * This function marks the buffer dirty but does not increment its
977 _hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
978 int *errorp
, struct hammer_buffer
**bufferp
)
980 hammer_buffer_t buffer
;
981 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
983 buf_offset
&= ~HAMMER_BUFMASK64
;
986 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
987 buffer
->zoneX_offset
!= buf_offset
)) {
989 hammer_rel_buffer(buffer
, 0);
990 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 1, errorp
);
997 * Return a pointer to the buffer data.
1002 return((char *)buffer
->ondisk
+ xoff
);
1006 hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
,
1007 int *errorp
, struct hammer_buffer
**bufferp
)
1009 return(_hammer_bnew(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
1013 hammer_bnew_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
1014 int *errorp
, struct hammer_buffer
**bufferp
)
1016 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
1017 return(_hammer_bnew(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
1020 /************************************************************************
1022 ************************************************************************
1024 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing
1025 * method used by the HAMMER filesystem.
1027 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY
1028 * associated with its buffer, and will only referenced the buffer while
1029 * the node itself is referenced.
1031 * A hammer_node can also be passively associated with other HAMMER
1032 * structures, such as inodes, while retaining 0 references. These
1033 * associations can be cleared backwards using a pointer-to-pointer in
1036 * This allows the HAMMER implementation to cache hammer_nodes long-term
1037 * and short-cut a great deal of the infrastructure's complexity. In
1038 * most cases a cached node can be reacquired without having to dip into
1039 * either the buffer or cluster management code.
1041 * The caller must pass a referenced cluster on call and will retain
1042 * ownership of the reference on return. The node will acquire its own
1043 * additional references, if necessary.
1046 hammer_get_node(hammer_mount_t hmp
, hammer_off_t node_offset
,
1047 int isnew
, int *errorp
)
1051 KKASSERT((node_offset
& HAMMER_OFF_ZONE_MASK
) == HAMMER_ZONE_BTREE
);
1054 * Locate the structure, allocating one if necessary.
1057 node
= RB_LOOKUP(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node_offset
);
1059 ++hammer_count_nodes
;
1060 node
= kmalloc(sizeof(*node
), M_HAMMER
, M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
1061 node
->node_offset
= node_offset
;
1063 TAILQ_INIT(&node
->cursor_list
);
1064 TAILQ_INIT(&node
->cache_list
);
1065 if (RB_INSERT(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node
)) {
1066 --hammer_count_nodes
;
1067 kfree(node
, M_HAMMER
);
1071 hammer_ref(&node
->lock
);
1075 *errorp
= hammer_load_node(node
, isnew
);
1077 hammer_rel_node(node
);
1084 * Reference an already-referenced node.
1087 hammer_ref_node(hammer_node_t node
)
1089 KKASSERT(node
->lock
.refs
> 0 && node
->ondisk
!= NULL
);
1090 hammer_ref(&node
->lock
);
1094 * Load a node's on-disk data reference.
1097 hammer_load_node(hammer_node_t node
, int isnew
)
1099 hammer_buffer_t buffer
;
1100 hammer_off_t buf_offset
;
1105 hammer_lock_ex(&node
->lock
);
1106 if (node
->ondisk
== NULL
) {
1108 * This is a little confusing but the jist is that
1109 * node->buffer determines whether the node is on
1110 * the buffer's clist and node->ondisk determines
1111 * whether the buffer is referenced.
1113 * We could be racing a buffer release, in which case
1114 * node->buffer may become NULL while we are blocked
1115 * referencing the buffer.
1117 if ((buffer
= node
->buffer
) != NULL
) {
1118 error
= hammer_ref_buffer(buffer
);
1119 if (error
== 0 && node
->buffer
== NULL
) {
1120 TAILQ_INSERT_TAIL(&buffer
->clist
,
1122 node
->buffer
= buffer
;
1125 buf_offset
= node
->node_offset
& ~HAMMER_BUFMASK64
;
1126 buffer
= hammer_get_buffer(node
->hmp
, buf_offset
,
1127 HAMMER_BUFSIZE
, 0, &error
);
1129 KKASSERT(error
== 0);
1130 TAILQ_INSERT_TAIL(&buffer
->clist
,
1132 node
->buffer
= buffer
;
1137 node
->ondisk
= (void *)((char *)buffer
->ondisk
+
1138 (node
->node_offset
& HAMMER_BUFMASK
));
1140 (node
->flags
& HAMMER_NODE_CRCGOOD
) == 0) {
1141 if (hammer_crc_test_btree(node
->ondisk
) == 0)
1142 Debugger("CRC FAILED: B-TREE NODE");
1143 node
->flags
|= HAMMER_NODE_CRCGOOD
;
1148 hammer_unlock(&node
->lock
);
1153 * Safely reference a node, interlock against flushes via the IO subsystem.
1156 hammer_ref_node_safe(struct hammer_mount
*hmp
, hammer_node_cache_t cache
,
1163 hammer_ref(&node
->lock
);
1167 *errorp
= hammer_load_node(node
, 0);
1169 hammer_rel_node(node
);
1179 * Release a hammer_node. On the last release the node dereferences
1180 * its underlying buffer and may or may not be destroyed.
1183 hammer_rel_node(hammer_node_t node
)
1185 hammer_buffer_t buffer
;
1188 * If this isn't the last ref just decrement the ref count and
1191 if (node
->lock
.refs
> 1) {
1192 hammer_unref(&node
->lock
);
1197 * If there is no ondisk info or no buffer the node failed to load,
1198 * remove the last reference and destroy the node.
1200 if (node
->ondisk
== NULL
) {
1201 hammer_unref(&node
->lock
);
1202 hammer_flush_node(node
);
1203 /* node is stale now */
1208 * Do not disassociate the node from the buffer if it represents
1209 * a modified B-Tree node that still needs its crc to be generated.
1211 if (node
->flags
& HAMMER_NODE_NEEDSCRC
)
1215 * Do final cleanups and then either destroy the node and leave it
1216 * passively cached. The buffer reference is removed regardless.
1218 buffer
= node
->buffer
;
1219 node
->ondisk
= NULL
;
1221 if ((node
->flags
& HAMMER_NODE_FLUSH
) == 0) {
1222 hammer_unref(&node
->lock
);
1223 hammer_rel_buffer(buffer
, 0);
1230 hammer_unref(&node
->lock
);
1231 hammer_flush_node(node
);
1233 hammer_rel_buffer(buffer
, 0);
1237 * Free space on-media associated with a B-Tree node.
1240 hammer_delete_node(hammer_transaction_t trans
, hammer_node_t node
)
1242 KKASSERT((node
->flags
& HAMMER_NODE_DELETED
) == 0);
1243 node
->flags
|= HAMMER_NODE_DELETED
;
1244 hammer_blockmap_free(trans
, node
->node_offset
, sizeof(*node
->ondisk
));
1248 * Passively cache a referenced hammer_node. The caller may release
1249 * the node on return.
1252 hammer_cache_node(hammer_node_cache_t cache
, hammer_node_t node
)
1255 * If the node doesn't exist, or is being deleted, don't cache it!
1257 * The node can only ever be NULL in the I/O failure path.
1259 if (node
== NULL
|| (node
->flags
& HAMMER_NODE_DELETED
))
1261 if (cache
->node
== node
)
1264 hammer_uncache_node(cache
);
1265 if (node
->flags
& HAMMER_NODE_DELETED
)
1268 TAILQ_INSERT_TAIL(&node
->cache_list
, cache
, entry
);
1272 hammer_uncache_node(hammer_node_cache_t cache
)
1276 if ((node
= cache
->node
) != NULL
) {
1277 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1279 if (TAILQ_EMPTY(&node
->cache_list
))
1280 hammer_flush_node(node
);
1285 * Remove a node's cache references and destroy the node if it has no
1286 * other references or backing store.
1289 hammer_flush_node(hammer_node_t node
)
1291 hammer_node_cache_t cache
;
1292 hammer_buffer_t buffer
;
1294 while ((cache
= TAILQ_FIRST(&node
->cache_list
)) != NULL
) {
1295 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1298 if (node
->lock
.refs
== 0 && node
->ondisk
== NULL
) {
1299 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1300 RB_REMOVE(hammer_nod_rb_tree
, &node
->hmp
->rb_nods_root
, node
);
1301 if ((buffer
= node
->buffer
) != NULL
) {
1302 node
->buffer
= NULL
;
1303 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1304 /* buffer is unreferenced because ondisk is NULL */
1306 --hammer_count_nodes
;
1307 kfree(node
, M_HAMMER
);
1312 * Flush passively cached B-Tree nodes associated with this buffer.
1313 * This is only called when the buffer is about to be destroyed, so
1314 * none of the nodes should have any references. The buffer is locked.
1316 * We may be interlocked with the buffer.
1319 hammer_flush_buffer_nodes(hammer_buffer_t buffer
)
1323 while ((node
= TAILQ_FIRST(&buffer
->clist
)) != NULL
) {
1324 KKASSERT(node
->ondisk
== NULL
);
1325 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1327 if (node
->lock
.refs
== 0) {
1328 hammer_ref(&node
->lock
);
1329 node
->flags
|= HAMMER_NODE_FLUSH
;
1330 hammer_rel_node(node
);
1332 KKASSERT(node
->loading
!= 0);
1333 KKASSERT(node
->buffer
!= NULL
);
1334 buffer
= node
->buffer
;
1335 node
->buffer
= NULL
;
1336 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1337 /* buffer is unreferenced because ondisk is NULL */
1343 /************************************************************************
1345 ************************************************************************/
1348 * Allocate a B-Tree node.
1351 hammer_alloc_btree(hammer_transaction_t trans
, int *errorp
)
1353 hammer_buffer_t buffer
= NULL
;
1354 hammer_node_t node
= NULL
;
1355 hammer_off_t node_offset
;
1357 node_offset
= hammer_blockmap_alloc(trans
, HAMMER_ZONE_BTREE_INDEX
,
1358 sizeof(struct hammer_node_ondisk
),
1361 node
= hammer_get_node(trans
->hmp
, node_offset
, 1, errorp
);
1362 hammer_modify_node_noundo(trans
, node
);
1363 bzero(node
->ondisk
, sizeof(*node
->ondisk
));
1364 hammer_modify_node_done(node
);
1367 hammer_rel_buffer(buffer
, 0);
1372 * Allocate data. If the address of a data buffer is supplied then
1373 * any prior non-NULL *data_bufferp will be released and *data_bufferp
1374 * will be set to the related buffer. The caller must release it when
1375 * finally done. The initial *data_bufferp should be set to NULL by
1378 * The caller is responsible for making hammer_modify*() calls on the
1382 hammer_alloc_data(hammer_transaction_t trans
, int32_t data_len
,
1383 u_int16_t rec_type
, hammer_off_t
*data_offsetp
,
1384 struct hammer_buffer
**data_bufferp
, int *errorp
)
1394 case HAMMER_RECTYPE_INODE
:
1395 case HAMMER_RECTYPE_DIRENTRY
:
1396 case HAMMER_RECTYPE_EXT
:
1397 case HAMMER_RECTYPE_FIX
:
1398 case HAMMER_RECTYPE_PFS
:
1399 zone
= HAMMER_ZONE_META_INDEX
;
1401 case HAMMER_RECTYPE_DATA
:
1402 case HAMMER_RECTYPE_DB
:
1403 if (data_len
<= HAMMER_BUFSIZE
/ 2) {
1404 zone
= HAMMER_ZONE_SMALL_DATA_INDEX
;
1406 data_len
= (data_len
+ HAMMER_BUFMASK
) &
1408 zone
= HAMMER_ZONE_LARGE_DATA_INDEX
;
1412 panic("hammer_alloc_data: rec_type %04x unknown",
1414 zone
= 0; /* NOT REACHED */
1417 *data_offsetp
= hammer_blockmap_alloc(trans
, zone
,
1422 if (*errorp
== 0 && data_bufferp
) {
1424 data
= hammer_bread_ext(trans
->hmp
, *data_offsetp
,
1425 data_len
, errorp
, data_bufferp
);
1436 * Sync dirty buffers to the media and clean-up any loose ends.
1438 * These functions do not start the flusher going, they simply
1439 * queue everything up to the flusher.
1441 static int hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
);
1442 static int hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
);
1445 hammer_queue_inodes_flusher(hammer_mount_t hmp
, int waitfor
)
1447 struct hammer_sync_info info
;
1450 info
.waitfor
= waitfor
;
1451 if (waitfor
== MNT_WAIT
) {
1452 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
,
1453 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1455 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
|VMSC_NOWAIT
,
1456 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1462 * Filesystem sync. If doing a synchronous sync make a second pass on
1463 * the vnodes in case any were already flushing during the first pass,
1464 * and activate the flusher twice (the second time brings the UNDO FIFO's
1465 * start position up to the end position after the first call).
1468 hammer_sync_hmp(hammer_mount_t hmp
, int waitfor
)
1470 struct hammer_sync_info info
;
1473 info
.waitfor
= MNT_NOWAIT
;
1474 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_NOWAIT
,
1475 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1476 if (info
.error
== 0 && waitfor
== MNT_WAIT
) {
1477 info
.waitfor
= waitfor
;
1478 vmntvnodescan(hmp
->mp
, VMSC_GETVP
,
1479 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1481 if (waitfor
== MNT_WAIT
) {
1482 hammer_flusher_sync(hmp
);
1483 hammer_flusher_sync(hmp
);
1485 hammer_flusher_async(hmp
, NULL
);
1486 hammer_flusher_async(hmp
, NULL
);
1492 hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
)
1494 struct hammer_inode
*ip
;
1497 if (vp
->v_type
== VNON
|| ip
== NULL
||
1498 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1499 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1506 hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
)
1508 struct hammer_sync_info
*info
= data
;
1509 struct hammer_inode
*ip
;
1513 if (vp
->v_type
== VNON
|| vp
->v_type
== VBAD
||
1514 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1515 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1518 error
= VOP_FSYNC(vp
, MNT_NOWAIT
);
1520 info
->error
= error
;