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 1.69.2.3 2008/07/30 07:53:01 mneumann 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 hammer_io_init(&volume
->io
, hmp
, HAMMER_STRUCTURE_VOLUME
);
123 volume
->io
.offset
= 0LL;
124 volume
->io
.bytes
= HAMMER_BUFSIZE
;
127 * Get the device vnode
130 error
= nlookup_init(&nd
, volume
->vol_name
, UIO_SYSSPACE
, NLC_FOLLOW
);
132 error
= nlookup(&nd
);
134 error
= cache_vref(&nd
.nl_nch
, nd
.nl_cred
, &volume
->devvp
);
138 volume
->devvp
= devvp
;
142 if (vn_isdisk(volume
->devvp
, &error
)) {
143 error
= vfs_mountedon(volume
->devvp
);
147 count_udev(volume
->devvp
->v_umajor
, volume
->devvp
->v_uminor
) > 0) {
151 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
152 error
= vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
154 error
= VOP_OPEN(volume
->devvp
,
155 (ronly
? FREAD
: FREAD
|FWRITE
),
158 vn_unlock(volume
->devvp
);
161 hammer_free_volume(volume
);
164 volume
->devvp
->v_rdev
->si_mountpoint
= mp
;
168 * Extract the volume number from the volume header and do various
171 error
= bread(volume
->devvp
, 0LL, HAMMER_BUFSIZE
, &bp
);
174 ondisk
= (void *)bp
->b_data
;
175 if (ondisk
->vol_signature
!= HAMMER_FSBUF_VOLUME
) {
176 kprintf("hammer_mount: volume %s has an invalid header\n",
181 volume
->vol_no
= ondisk
->vol_no
;
182 volume
->buffer_base
= ondisk
->vol_buf_beg
;
183 volume
->vol_flags
= ondisk
->vol_flags
;
184 volume
->nblocks
= ondisk
->vol_nblocks
;
185 volume
->maxbuf_off
= HAMMER_ENCODE_RAW_BUFFER(volume
->vol_no
,
186 ondisk
->vol_buf_end
- ondisk
->vol_buf_beg
);
187 volume
->maxraw_off
= ondisk
->vol_buf_end
;
189 if (RB_EMPTY(&hmp
->rb_vols_root
)) {
190 hmp
->fsid
= ondisk
->vol_fsid
;
191 } else if (bcmp(&hmp
->fsid
, &ondisk
->vol_fsid
, sizeof(uuid_t
))) {
192 kprintf("hammer_mount: volume %s's fsid does not match "
193 "other volumes\n", volume
->vol_name
);
199 * Insert the volume structure into the red-black tree.
201 if (RB_INSERT(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
)) {
202 kprintf("hammer_mount: volume %s has a duplicate vol_no %d\n",
203 volume
->vol_name
, volume
->vol_no
);
208 * Set the root volume . HAMMER special cases rootvol the structure.
209 * We do not hold a ref because this would prevent related I/O
210 * from being flushed.
212 if (error
== 0 && ondisk
->vol_rootvol
== ondisk
->vol_no
) {
213 hmp
->rootvol
= volume
;
214 hmp
->nvolumes
= ondisk
->vol_count
;
219 hmp
->mp
->mnt_stat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
220 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
221 hmp
->mp
->mnt_vstat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
222 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
228 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/
230 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
231 VOP_CLOSE(volume
->devvp
, ronly
? FREAD
: FREAD
|FWRITE
);
232 hammer_free_volume(volume
);
238 * This is called for each volume when updating the mount point from
239 * read-write to read-only or vise-versa.
242 hammer_adjust_volume_mode(hammer_volume_t volume
, void *data __unused
)
245 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
246 if (volume
->io
.hmp
->ronly
) {
247 /* do not call vinvalbuf */
248 VOP_OPEN(volume
->devvp
, FREAD
, FSCRED
, NULL
);
249 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
251 /* do not call vinvalbuf */
252 VOP_OPEN(volume
->devvp
, FREAD
|FWRITE
, FSCRED
, NULL
);
253 VOP_CLOSE(volume
->devvp
, FREAD
);
255 vn_unlock(volume
->devvp
);
261 * Unload and free a HAMMER volume. Must return >= 0 to continue scan
262 * so returns -1 on failure.
265 hammer_unload_volume(hammer_volume_t volume
, void *data __unused
)
267 struct hammer_mount
*hmp
= volume
->io
.hmp
;
268 int ronly
= ((hmp
->mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
272 * Clean up the root volume pointer, which is held unlocked in hmp.
274 if (hmp
->rootvol
== volume
)
278 * We must not flush a dirty buffer to disk on umount. It should
279 * have already been dealt with by the flusher, or we may be in
280 * catastrophic failure.
282 hammer_io_clear_modify(&volume
->io
, 1);
283 volume
->io
.waitdep
= 1;
284 bp
= hammer_io_release(&volume
->io
, 1);
287 * Clean up the persistent ref ioerror might have on the volume
289 if (volume
->io
.ioerror
) {
290 volume
->io
.ioerror
= 0;
291 hammer_unref(&volume
->io
.lock
);
295 * There should be no references on the volume, no clusters, and
298 KKASSERT(volume
->io
.lock
.refs
== 0);
302 volume
->ondisk
= NULL
;
304 if (volume
->devvp
->v_rdev
&&
305 volume
->devvp
->v_rdev
->si_mountpoint
== hmp
->mp
307 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
311 * Make sure we don't sync anything to disk if we
312 * are in read-only mode (1) or critically-errored
313 * (2). Note that there may be dirty buffers in
314 * normal read-only mode from crash recovery.
316 vinvalbuf(volume
->devvp
, 0, 0, 0);
317 VOP_CLOSE(volume
->devvp
, FREAD
);
320 * Normal termination, save any dirty buffers
321 * (XXX there really shouldn't be any).
323 vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
324 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
329 * Destroy the structure
331 RB_REMOVE(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
);
332 hammer_free_volume(volume
);
338 hammer_free_volume(hammer_volume_t volume
)
340 if (volume
->vol_name
) {
341 kfree(volume
->vol_name
, M_HAMMER
);
342 volume
->vol_name
= NULL
;
345 vrele(volume
->devvp
);
346 volume
->devvp
= NULL
;
348 --hammer_count_volumes
;
349 kfree(volume
, M_HAMMER
);
353 * Get a HAMMER volume. The volume must already exist.
356 hammer_get_volume(struct hammer_mount
*hmp
, int32_t vol_no
, int *errorp
)
358 struct hammer_volume
*volume
;
361 * Locate the volume structure
363 volume
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, vol_no
);
364 if (volume
== NULL
) {
368 hammer_ref(&volume
->io
.lock
);
371 * Deal with on-disk info
373 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
374 *errorp
= hammer_load_volume(volume
);
376 hammer_rel_volume(volume
, 1);
386 hammer_ref_volume(hammer_volume_t volume
)
390 hammer_ref(&volume
->io
.lock
);
393 * Deal with on-disk info
395 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
396 error
= hammer_load_volume(volume
);
398 hammer_rel_volume(volume
, 1);
406 hammer_get_root_volume(struct hammer_mount
*hmp
, int *errorp
)
408 hammer_volume_t volume
;
410 volume
= hmp
->rootvol
;
411 KKASSERT(volume
!= NULL
);
412 hammer_ref(&volume
->io
.lock
);
415 * Deal with on-disk info
417 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
418 *errorp
= hammer_load_volume(volume
);
420 hammer_rel_volume(volume
, 1);
430 * Load a volume's on-disk information. The volume must be referenced and
431 * not locked. We temporarily acquire an exclusive lock to interlock
432 * against releases or multiple get's.
435 hammer_load_volume(hammer_volume_t volume
)
439 ++volume
->io
.loading
;
440 hammer_lock_ex(&volume
->io
.lock
);
442 if (volume
->ondisk
== NULL
) {
443 error
= hammer_io_read(volume
->devvp
, &volume
->io
,
446 volume
->ondisk
= (void *)volume
->io
.bp
->b_data
;
450 --volume
->io
.loading
;
451 hammer_unlock(&volume
->io
.lock
);
456 * Release a volume. Call hammer_io_release on the last reference. We have
457 * to acquire an exclusive lock to interlock against volume->ondisk tests
458 * in hammer_load_volume(), and hammer_io_release() also expects an exclusive
461 * Volumes are not unloaded from memory during normal operation.
464 hammer_rel_volume(hammer_volume_t volume
, int flush
)
466 struct buf
*bp
= NULL
;
469 if (volume
->io
.lock
.refs
== 1) {
470 ++volume
->io
.loading
;
471 hammer_lock_ex(&volume
->io
.lock
);
472 if (volume
->io
.lock
.refs
== 1) {
473 volume
->ondisk
= NULL
;
474 bp
= hammer_io_release(&volume
->io
, flush
);
476 --volume
->io
.loading
;
477 hammer_unlock(&volume
->io
.lock
);
479 hammer_unref(&volume
->io
.lock
);
486 hammer_mountcheck_volumes(struct hammer_mount
*hmp
)
491 for (i
= 0; i
< hmp
->nvolumes
; ++i
) {
492 vol
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, i
);
499 /************************************************************************
501 ************************************************************************
503 * Manage buffers. Currently all blockmap-backed zones are translated
504 * to zone-2 buffer offsets.
507 hammer_get_buffer(hammer_mount_t hmp
, hammer_off_t buf_offset
,
508 int bytes
, int isnew
, int *errorp
)
510 hammer_buffer_t buffer
;
511 hammer_volume_t volume
;
512 hammer_off_t zone2_offset
;
513 hammer_io_type_t iotype
;
517 buf_offset
&= ~HAMMER_BUFMASK64
;
520 * Shortcut if the buffer is already cached
522 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buf_offset
);
524 if (buffer
->io
.lock
.refs
== 0)
525 ++hammer_count_refedbufs
;
526 hammer_ref(&buffer
->io
.lock
);
529 * Onced refed the ondisk field will not be cleared by
532 if (buffer
->ondisk
&& buffer
->io
.loading
== 0) {
538 * The buffer is no longer loose if it has a ref, and
539 * cannot become loose once it gains a ref. Loose
540 * buffers will never be in a modified state. This should
541 * only occur on the 0->1 transition of refs.
543 * lose_list can be modified via a biodone() interrupt.
545 if (buffer
->io
.mod_list
== &hmp
->lose_list
) {
546 crit_enter(); /* biodone race against list */
547 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
,
550 buffer
->io
.mod_list
= NULL
;
551 KKASSERT(buffer
->io
.modified
== 0);
557 * What is the buffer class?
559 zone
= HAMMER_ZONE_DECODE(buf_offset
);
562 case HAMMER_ZONE_LARGE_DATA_INDEX
:
563 case HAMMER_ZONE_SMALL_DATA_INDEX
:
564 iotype
= HAMMER_STRUCTURE_DATA_BUFFER
;
566 case HAMMER_ZONE_UNDO_INDEX
:
567 iotype
= HAMMER_STRUCTURE_UNDO_BUFFER
;
569 case HAMMER_ZONE_META_INDEX
:
572 * NOTE: inode data and directory entries are placed in this
573 * zone. inode atime/mtime is updated in-place and thus
574 * buffers containing inodes must be synchronized as
575 * meta-buffers, same as buffers containing B-Tree info.
577 iotype
= HAMMER_STRUCTURE_META_BUFFER
;
582 * Handle blockmap offset translations
584 if (zone
>= HAMMER_ZONE_BTREE_INDEX
) {
585 zone2_offset
= hammer_blockmap_lookup(hmp
, buf_offset
, errorp
);
586 } else if (zone
== HAMMER_ZONE_UNDO_INDEX
) {
587 zone2_offset
= hammer_undo_lookup(hmp
, buf_offset
, errorp
);
589 KKASSERT(zone
== HAMMER_ZONE_RAW_BUFFER_INDEX
);
590 zone2_offset
= buf_offset
;
597 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset
600 KKASSERT((zone2_offset
& HAMMER_OFF_ZONE_MASK
) ==
601 HAMMER_ZONE_RAW_BUFFER
);
602 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
603 volume
= hammer_get_volume(hmp
, vol_no
, errorp
);
607 KKASSERT(zone2_offset
< volume
->maxbuf_off
);
610 * Allocate a new buffer structure. We will check for races later.
612 ++hammer_count_buffers
;
613 buffer
= kmalloc(sizeof(*buffer
), M_HAMMER
,
614 M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
615 buffer
->zone2_offset
= zone2_offset
;
616 buffer
->zoneX_offset
= buf_offset
;
617 buffer
->volume
= volume
;
619 hammer_io_init(&buffer
->io
, hmp
, 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 hammer
657 * buffers must be fully synced to disk before we can issue the direct-read.
659 * This code path is not considered critical as only the rebocker and
660 * mirror-write code will create large-data buffers via the HAMMER buffer
661 * subsystem. They do that because they operate at the B-Tree level and
662 * do not access the vnode/inode structures.
665 hammer_sync_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
, int bytes
)
667 hammer_buffer_t buffer
;
670 KKASSERT((base_offset
& HAMMER_OFF_ZONE_MASK
) ==
671 HAMMER_ZONE_LARGE_DATA
);
674 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
676 if (buffer
&& buffer
->io
.modified
) {
677 error
= hammer_ref_buffer(buffer
);
678 if (error
== 0 && buffer
->io
.modified
) {
679 hammer_io_write_interlock(&buffer
->io
);
680 hammer_io_flush(&buffer
->io
);
681 hammer_io_done_interlock(&buffer
->io
);
682 hammer_io_wait(&buffer
->io
);
683 hammer_rel_buffer(buffer
, 0);
686 base_offset
+= HAMMER_BUFSIZE
;
687 bytes
-= HAMMER_BUFSIZE
;
692 * Destroy all buffers covering the specified zoneX offset range. This
693 * is called when the related blockmap layer2 entry is freed or when
694 * a direct write bypasses our buffer/buffer-cache subsystem.
696 * The buffers may be referenced by the caller itself. Setting reclaim
697 * will cause the buffer to be destroyed when it's ref count reaches zero.
700 hammer_del_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
,
701 hammer_off_t zone2_offset
, int bytes
)
703 hammer_buffer_t buffer
;
704 hammer_volume_t volume
;
708 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
709 volume
= hammer_get_volume(hmp
, vol_no
, &error
);
710 KKASSERT(error
== 0);
713 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
716 error
= hammer_ref_buffer(buffer
);
718 KKASSERT(buffer
->zone2_offset
== zone2_offset
);
719 hammer_io_clear_modify(&buffer
->io
, 1);
720 buffer
->io
.reclaim
= 1;
721 KKASSERT(buffer
->volume
== volume
);
722 hammer_rel_buffer(buffer
, 0);
725 hammer_io_inval(volume
, zone2_offset
);
727 base_offset
+= HAMMER_BUFSIZE
;
728 zone2_offset
+= HAMMER_BUFSIZE
;
729 bytes
-= HAMMER_BUFSIZE
;
731 hammer_rel_volume(volume
, 0);
735 hammer_load_buffer(hammer_buffer_t buffer
, int isnew
)
737 hammer_volume_t volume
;
741 * Load the buffer's on-disk info
743 volume
= buffer
->volume
;
744 ++buffer
->io
.loading
;
745 hammer_lock_ex(&buffer
->io
.lock
);
747 if (hammer_debug_io
& 0x0001) {
748 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n",
749 buffer
->zoneX_offset
, buffer
->zone2_offset
, isnew
,
753 if (buffer
->ondisk
== NULL
) {
755 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
757 error
= hammer_io_read(volume
->devvp
, &buffer
->io
,
761 buffer
->ondisk
= (void *)buffer
->io
.bp
->b_data
;
763 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
767 --buffer
->io
.loading
;
768 hammer_unlock(&buffer
->io
.lock
);
773 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue.
774 * This routine is only called during unmount.
777 hammer_unload_buffer(hammer_buffer_t buffer
, void *data __unused
)
780 * Clean up the persistent ref ioerror might have on the buffer
781 * and acquire a ref (steal ioerror's if we can).
783 if (buffer
->io
.ioerror
) {
784 buffer
->io
.ioerror
= 0;
786 if (buffer
->io
.lock
.refs
== 0)
787 ++hammer_count_refedbufs
;
788 hammer_ref(&buffer
->io
.lock
);
792 * We must not flush a dirty buffer to disk on umount. It should
793 * have already been dealt with by the flusher, or we may be in
794 * catastrophic failure.
796 hammer_io_clear_modify(&buffer
->io
, 1);
797 hammer_flush_buffer_nodes(buffer
);
798 KKASSERT(buffer
->io
.lock
.refs
== 1);
799 hammer_rel_buffer(buffer
, 2);
804 * Reference a buffer that is either already referenced or via a specially
805 * handled pointer (aka cursor->buffer).
808 hammer_ref_buffer(hammer_buffer_t buffer
)
812 if (buffer
->io
.lock
.refs
== 0)
813 ++hammer_count_refedbufs
;
814 hammer_ref(&buffer
->io
.lock
);
817 * At this point a biodone() will not touch the buffer other then
818 * incidental bits. However, lose_list can be modified via
819 * a biodone() interrupt.
823 if (buffer
->io
.mod_list
== &buffer
->io
.hmp
->lose_list
) {
825 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
, mod_entry
);
826 buffer
->io
.mod_list
= NULL
;
830 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
831 error
= hammer_load_buffer(buffer
, 0);
833 hammer_rel_buffer(buffer
, 1);
835 * NOTE: buffer pointer can become stale after
846 * Release a buffer. We have to deal with several places where
847 * another thread can ref the buffer.
849 * Only destroy the structure itself if the related buffer cache buffer
850 * was disassociated from it. This ties the management of the structure
851 * to the buffer cache subsystem. buffer->ondisk determines whether the
852 * embedded io is referenced or not.
855 hammer_rel_buffer(hammer_buffer_t buffer
, int flush
)
857 hammer_volume_t volume
;
858 struct buf
*bp
= NULL
;
862 if (buffer
->io
.lock
.refs
== 1) {
863 ++buffer
->io
.loading
; /* force interlock check */
864 hammer_lock_ex(&buffer
->io
.lock
);
865 if (buffer
->io
.lock
.refs
== 1) {
866 bp
= hammer_io_release(&buffer
->io
, flush
);
868 if (buffer
->io
.lock
.refs
== 1)
869 --hammer_count_refedbufs
;
871 if (buffer
->io
.bp
== NULL
&&
872 buffer
->io
.lock
.refs
== 1) {
876 * NOTE: It is impossible for any associated
877 * B-Tree nodes to have refs if the buffer
878 * has no additional refs.
880 RB_REMOVE(hammer_buf_rb_tree
,
881 &buffer
->io
.hmp
->rb_bufs_root
,
883 volume
= buffer
->volume
;
884 buffer
->volume
= NULL
; /* sanity */
885 hammer_rel_volume(volume
, 0);
886 hammer_io_clear_modlist(&buffer
->io
);
887 hammer_flush_buffer_nodes(buffer
);
888 KKASSERT(TAILQ_EMPTY(&buffer
->clist
));
892 --buffer
->io
.loading
;
893 hammer_unlock(&buffer
->io
.lock
);
895 hammer_unref(&buffer
->io
.lock
);
900 --hammer_count_buffers
;
901 kfree(buffer
, M_HAMMER
);
906 * Access the filesystem buffer containing the specified hammer offset.
907 * buf_offset is a conglomeration of the volume number and vol_buf_beg
908 * relative buffer offset. It must also have bit 55 set to be valid.
909 * (see hammer_off_t in hammer_disk.h).
911 * Any prior buffer in *bufferp will be released and replaced by the
916 _hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
917 int *errorp
, struct hammer_buffer
**bufferp
)
919 hammer_buffer_t buffer
;
920 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
922 buf_offset
&= ~HAMMER_BUFMASK64
;
923 KKASSERT((buf_offset
& HAMMER_OFF_ZONE_MASK
) != 0);
926 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
927 buffer
->zoneX_offset
!= buf_offset
)) {
929 hammer_rel_buffer(buffer
, 0);
930 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 0, errorp
);
937 * Return a pointer to the buffer data.
942 return((char *)buffer
->ondisk
+ xoff
);
946 hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
,
947 int *errorp
, struct hammer_buffer
**bufferp
)
949 return(_hammer_bread(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
953 hammer_bread_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
954 int *errorp
, struct hammer_buffer
**bufferp
)
956 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
957 return(_hammer_bread(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
961 * Access the filesystem buffer containing the specified hammer offset.
962 * No disk read operation occurs. The result buffer may contain garbage.
964 * Any prior buffer in *bufferp will be released and replaced by the
967 * This function marks the buffer dirty but does not increment its
972 _hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
973 int *errorp
, struct hammer_buffer
**bufferp
)
975 hammer_buffer_t buffer
;
976 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
978 buf_offset
&= ~HAMMER_BUFMASK64
;
981 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
982 buffer
->zoneX_offset
!= buf_offset
)) {
984 hammer_rel_buffer(buffer
, 0);
985 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 1, errorp
);
992 * Return a pointer to the buffer data.
997 return((char *)buffer
->ondisk
+ xoff
);
1001 hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
,
1002 int *errorp
, struct hammer_buffer
**bufferp
)
1004 return(_hammer_bnew(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
1008 hammer_bnew_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
1009 int *errorp
, struct hammer_buffer
**bufferp
)
1011 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
1012 return(_hammer_bnew(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
1015 /************************************************************************
1017 ************************************************************************
1019 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing
1020 * method used by the HAMMER filesystem.
1022 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY
1023 * associated with its buffer, and will only referenced the buffer while
1024 * the node itself is referenced.
1026 * A hammer_node can also be passively associated with other HAMMER
1027 * structures, such as inodes, while retaining 0 references. These
1028 * associations can be cleared backwards using a pointer-to-pointer in
1031 * This allows the HAMMER implementation to cache hammer_nodes long-term
1032 * and short-cut a great deal of the infrastructure's complexity. In
1033 * most cases a cached node can be reacquired without having to dip into
1034 * either the buffer or cluster management code.
1036 * The caller must pass a referenced cluster on call and will retain
1037 * ownership of the reference on return. The node will acquire its own
1038 * additional references, if necessary.
1041 hammer_get_node(hammer_mount_t hmp
, hammer_off_t node_offset
,
1042 int isnew
, int *errorp
)
1046 KKASSERT((node_offset
& HAMMER_OFF_ZONE_MASK
) == HAMMER_ZONE_BTREE
);
1049 * Locate the structure, allocating one if necessary.
1052 node
= RB_LOOKUP(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node_offset
);
1054 ++hammer_count_nodes
;
1055 node
= kmalloc(sizeof(*node
), M_HAMMER
, M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
1056 node
->node_offset
= node_offset
;
1058 TAILQ_INIT(&node
->cursor_list
);
1059 TAILQ_INIT(&node
->cache_list
);
1060 if (RB_INSERT(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node
)) {
1061 --hammer_count_nodes
;
1062 kfree(node
, M_HAMMER
);
1066 hammer_ref(&node
->lock
);
1070 *errorp
= hammer_load_node(node
, isnew
);
1072 hammer_rel_node(node
);
1079 * Reference an already-referenced node.
1082 hammer_ref_node(hammer_node_t node
)
1084 KKASSERT(node
->lock
.refs
> 0 && node
->ondisk
!= NULL
);
1085 hammer_ref(&node
->lock
);
1089 * Load a node's on-disk data reference.
1092 hammer_load_node(hammer_node_t node
, int isnew
)
1094 hammer_buffer_t buffer
;
1095 hammer_off_t buf_offset
;
1100 hammer_lock_ex(&node
->lock
);
1101 if (node
->ondisk
== NULL
) {
1103 * This is a little confusing but the jist is that
1104 * node->buffer determines whether the node is on
1105 * the buffer's clist and node->ondisk determines
1106 * whether the buffer is referenced.
1108 * We could be racing a buffer release, in which case
1109 * node->buffer may become NULL while we are blocked
1110 * referencing the buffer.
1112 if ((buffer
= node
->buffer
) != NULL
) {
1113 error
= hammer_ref_buffer(buffer
);
1114 if (error
== 0 && node
->buffer
== NULL
) {
1115 TAILQ_INSERT_TAIL(&buffer
->clist
,
1117 node
->buffer
= buffer
;
1120 buf_offset
= node
->node_offset
& ~HAMMER_BUFMASK64
;
1121 buffer
= hammer_get_buffer(node
->hmp
, buf_offset
,
1122 HAMMER_BUFSIZE
, 0, &error
);
1124 KKASSERT(error
== 0);
1125 TAILQ_INSERT_TAIL(&buffer
->clist
,
1127 node
->buffer
= buffer
;
1132 node
->ondisk
= (void *)((char *)buffer
->ondisk
+
1133 (node
->node_offset
& HAMMER_BUFMASK
));
1135 (node
->flags
& HAMMER_NODE_CRCGOOD
) == 0) {
1136 if (hammer_crc_test_btree(node
->ondisk
) == 0)
1137 Debugger("CRC FAILED: B-TREE NODE");
1138 node
->flags
|= HAMMER_NODE_CRCGOOD
;
1143 hammer_unlock(&node
->lock
);
1148 * Safely reference a node, interlock against flushes via the IO subsystem.
1151 hammer_ref_node_safe(struct hammer_mount
*hmp
, hammer_node_cache_t cache
,
1158 hammer_ref(&node
->lock
);
1162 *errorp
= hammer_load_node(node
, 0);
1164 hammer_rel_node(node
);
1174 * Release a hammer_node. On the last release the node dereferences
1175 * its underlying buffer and may or may not be destroyed.
1178 hammer_rel_node(hammer_node_t node
)
1180 hammer_buffer_t buffer
;
1183 * If this isn't the last ref just decrement the ref count and
1186 if (node
->lock
.refs
> 1) {
1187 hammer_unref(&node
->lock
);
1192 * If there is no ondisk info or no buffer the node failed to load,
1193 * remove the last reference and destroy the node.
1195 if (node
->ondisk
== NULL
) {
1196 hammer_unref(&node
->lock
);
1197 hammer_flush_node(node
);
1198 /* node is stale now */
1203 * Do not disassociate the node from the buffer if it represents
1204 * a modified B-Tree node that still needs its crc to be generated.
1206 if (node
->flags
& HAMMER_NODE_NEEDSCRC
)
1210 * Do final cleanups and then either destroy the node and leave it
1211 * passively cached. The buffer reference is removed regardless.
1213 buffer
= node
->buffer
;
1214 node
->ondisk
= NULL
;
1216 if ((node
->flags
& HAMMER_NODE_FLUSH
) == 0) {
1217 hammer_unref(&node
->lock
);
1218 hammer_rel_buffer(buffer
, 0);
1225 hammer_unref(&node
->lock
);
1226 hammer_flush_node(node
);
1228 hammer_rel_buffer(buffer
, 0);
1232 * Free space on-media associated with a B-Tree node.
1235 hammer_delete_node(hammer_transaction_t trans
, hammer_node_t node
)
1237 KKASSERT((node
->flags
& HAMMER_NODE_DELETED
) == 0);
1238 node
->flags
|= HAMMER_NODE_DELETED
;
1239 hammer_blockmap_free(trans
, node
->node_offset
, sizeof(*node
->ondisk
));
1243 * Passively cache a referenced hammer_node. The caller may release
1244 * the node on return.
1247 hammer_cache_node(hammer_node_cache_t cache
, hammer_node_t node
)
1250 * If the node doesn't exist, or is being deleted, don't cache it!
1252 * The node can only ever be NULL in the I/O failure path.
1254 if (node
== NULL
|| (node
->flags
& HAMMER_NODE_DELETED
))
1256 if (cache
->node
== node
)
1259 hammer_uncache_node(cache
);
1260 if (node
->flags
& HAMMER_NODE_DELETED
)
1263 TAILQ_INSERT_TAIL(&node
->cache_list
, cache
, entry
);
1267 hammer_uncache_node(hammer_node_cache_t cache
)
1271 if ((node
= cache
->node
) != NULL
) {
1272 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1274 if (TAILQ_EMPTY(&node
->cache_list
))
1275 hammer_flush_node(node
);
1280 * Remove a node's cache references and destroy the node if it has no
1281 * other references or backing store.
1284 hammer_flush_node(hammer_node_t node
)
1286 hammer_node_cache_t cache
;
1287 hammer_buffer_t buffer
;
1289 while ((cache
= TAILQ_FIRST(&node
->cache_list
)) != NULL
) {
1290 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1293 if (node
->lock
.refs
== 0 && node
->ondisk
== NULL
) {
1294 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1295 RB_REMOVE(hammer_nod_rb_tree
, &node
->hmp
->rb_nods_root
, node
);
1296 if ((buffer
= node
->buffer
) != NULL
) {
1297 node
->buffer
= NULL
;
1298 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1299 /* buffer is unreferenced because ondisk is NULL */
1301 --hammer_count_nodes
;
1302 kfree(node
, M_HAMMER
);
1307 * Flush passively cached B-Tree nodes associated with this buffer.
1308 * This is only called when the buffer is about to be destroyed, so
1309 * none of the nodes should have any references. The buffer is locked.
1311 * We may be interlocked with the buffer.
1314 hammer_flush_buffer_nodes(hammer_buffer_t buffer
)
1318 while ((node
= TAILQ_FIRST(&buffer
->clist
)) != NULL
) {
1319 KKASSERT(node
->ondisk
== NULL
);
1320 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1322 if (node
->lock
.refs
== 0) {
1323 hammer_ref(&node
->lock
);
1324 node
->flags
|= HAMMER_NODE_FLUSH
;
1325 hammer_rel_node(node
);
1327 KKASSERT(node
->loading
!= 0);
1328 KKASSERT(node
->buffer
!= NULL
);
1329 buffer
= node
->buffer
;
1330 node
->buffer
= NULL
;
1331 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1332 /* buffer is unreferenced because ondisk is NULL */
1338 /************************************************************************
1340 ************************************************************************/
1343 * Allocate a B-Tree node.
1346 hammer_alloc_btree(hammer_transaction_t trans
, int *errorp
)
1348 hammer_buffer_t buffer
= NULL
;
1349 hammer_node_t node
= NULL
;
1350 hammer_off_t node_offset
;
1352 node_offset
= hammer_blockmap_alloc(trans
, HAMMER_ZONE_BTREE_INDEX
,
1353 sizeof(struct hammer_node_ondisk
),
1356 node
= hammer_get_node(trans
->hmp
, node_offset
, 1, errorp
);
1357 hammer_modify_node_noundo(trans
, node
);
1358 bzero(node
->ondisk
, sizeof(*node
->ondisk
));
1359 hammer_modify_node_done(node
);
1362 hammer_rel_buffer(buffer
, 0);
1367 * Allocate data. If the address of a data buffer is supplied then
1368 * any prior non-NULL *data_bufferp will be released and *data_bufferp
1369 * will be set to the related buffer. The caller must release it when
1370 * finally done. The initial *data_bufferp should be set to NULL by
1373 * The caller is responsible for making hammer_modify*() calls on the
1377 hammer_alloc_data(hammer_transaction_t trans
, int32_t data_len
,
1378 u_int16_t rec_type
, hammer_off_t
*data_offsetp
,
1379 struct hammer_buffer
**data_bufferp
, int *errorp
)
1389 case HAMMER_RECTYPE_INODE
:
1390 case HAMMER_RECTYPE_DIRENTRY
:
1391 case HAMMER_RECTYPE_EXT
:
1392 case HAMMER_RECTYPE_FIX
:
1393 case HAMMER_RECTYPE_PFS
:
1394 zone
= HAMMER_ZONE_META_INDEX
;
1396 case HAMMER_RECTYPE_DATA
:
1397 case HAMMER_RECTYPE_DB
:
1398 if (data_len
<= HAMMER_BUFSIZE
/ 2) {
1399 zone
= HAMMER_ZONE_SMALL_DATA_INDEX
;
1401 data_len
= (data_len
+ HAMMER_BUFMASK
) &
1403 zone
= HAMMER_ZONE_LARGE_DATA_INDEX
;
1407 panic("hammer_alloc_data: rec_type %04x unknown",
1409 zone
= 0; /* NOT REACHED */
1412 *data_offsetp
= hammer_blockmap_alloc(trans
, zone
,
1417 if (*errorp
== 0 && data_bufferp
) {
1419 data
= hammer_bread_ext(trans
->hmp
, *data_offsetp
,
1420 data_len
, errorp
, data_bufferp
);
1431 * Sync dirty buffers to the media and clean-up any loose ends.
1433 * These functions do not start the flusher going, they simply
1434 * queue everything up to the flusher.
1436 static int hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
);
1437 static int hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
);
1440 hammer_queue_inodes_flusher(hammer_mount_t hmp
, int waitfor
)
1442 struct hammer_sync_info info
;
1445 info
.waitfor
= waitfor
;
1446 if (waitfor
== MNT_WAIT
) {
1447 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
,
1448 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1450 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
|VMSC_NOWAIT
,
1451 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1457 * Filesystem sync. If doing a synchronous sync make a second pass on
1458 * the vnodes in case any were already flushing during the first pass,
1459 * and activate the flusher twice (the second time brings the UNDO FIFO's
1460 * start position up to the end position after the first call).
1463 hammer_sync_hmp(hammer_mount_t hmp
, int waitfor
)
1465 struct hammer_sync_info info
;
1468 info
.waitfor
= MNT_NOWAIT
;
1469 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_NOWAIT
,
1470 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1471 if (info
.error
== 0 && waitfor
== MNT_WAIT
) {
1472 info
.waitfor
= waitfor
;
1473 vmntvnodescan(hmp
->mp
, VMSC_GETVP
,
1474 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1476 if (waitfor
== MNT_WAIT
) {
1477 hammer_flusher_sync(hmp
);
1478 hammer_flusher_sync(hmp
);
1480 hammer_flusher_async(hmp
, NULL
);
1486 hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
)
1488 struct hammer_inode
*ip
;
1491 if (vp
->v_type
== VNON
|| ip
== NULL
||
1492 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1493 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1500 hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
)
1502 struct hammer_sync_info
*info
= data
;
1503 struct hammer_inode
*ip
;
1507 if (vp
->v_type
== VNON
|| vp
->v_type
== VBAD
||
1508 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1509 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1512 error
= VOP_FSYNC(vp
, MNT_NOWAIT
);
1514 info
->error
= error
;