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
), hmp
->m_misc
, M_WAITOK
|M_ZERO
);
121 volume
->vol_name
= kstrdup(volname
, hmp
->m_misc
);
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 hammer_mount_t 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 hammer_mount_t hmp
= volume
->io
.hmp
;
343 if (volume
->vol_name
) {
344 kfree(volume
->vol_name
, hmp
->m_misc
);
345 volume
->vol_name
= NULL
;
348 vrele(volume
->devvp
);
349 volume
->devvp
= NULL
;
351 --hammer_count_volumes
;
352 kfree(volume
, hmp
->m_misc
);
356 * Get a HAMMER volume. The volume must already exist.
359 hammer_get_volume(struct hammer_mount
*hmp
, int32_t vol_no
, int *errorp
)
361 struct hammer_volume
*volume
;
364 * Locate the volume structure
366 volume
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, vol_no
);
367 if (volume
== NULL
) {
371 hammer_ref(&volume
->io
.lock
);
374 * Deal with on-disk info
376 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
377 *errorp
= hammer_load_volume(volume
);
379 hammer_rel_volume(volume
, 1);
389 hammer_ref_volume(hammer_volume_t volume
)
393 hammer_ref(&volume
->io
.lock
);
396 * Deal with on-disk info
398 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
399 error
= hammer_load_volume(volume
);
401 hammer_rel_volume(volume
, 1);
409 hammer_get_root_volume(struct hammer_mount
*hmp
, int *errorp
)
411 hammer_volume_t volume
;
413 volume
= hmp
->rootvol
;
414 KKASSERT(volume
!= NULL
);
415 hammer_ref(&volume
->io
.lock
);
418 * Deal with on-disk info
420 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
421 *errorp
= hammer_load_volume(volume
);
423 hammer_rel_volume(volume
, 1);
433 * Load a volume's on-disk information. The volume must be referenced and
434 * not locked. We temporarily acquire an exclusive lock to interlock
435 * against releases or multiple get's.
438 hammer_load_volume(hammer_volume_t volume
)
442 ++volume
->io
.loading
;
443 hammer_lock_ex(&volume
->io
.lock
);
445 if (volume
->ondisk
== NULL
) {
446 error
= hammer_io_read(volume
->devvp
, &volume
->io
,
449 volume
->ondisk
= (void *)volume
->io
.bp
->b_data
;
453 --volume
->io
.loading
;
454 hammer_unlock(&volume
->io
.lock
);
459 * Release a volume. Call hammer_io_release on the last reference. We have
460 * to acquire an exclusive lock to interlock against volume->ondisk tests
461 * in hammer_load_volume(), and hammer_io_release() also expects an exclusive
464 * Volumes are not unloaded from memory during normal operation.
467 hammer_rel_volume(hammer_volume_t volume
, int flush
)
469 struct buf
*bp
= NULL
;
472 if (volume
->io
.lock
.refs
== 1) {
473 ++volume
->io
.loading
;
474 hammer_lock_ex(&volume
->io
.lock
);
475 if (volume
->io
.lock
.refs
== 1) {
476 volume
->ondisk
= NULL
;
477 bp
= hammer_io_release(&volume
->io
, flush
);
479 --volume
->io
.loading
;
480 hammer_unlock(&volume
->io
.lock
);
482 hammer_unref(&volume
->io
.lock
);
489 hammer_mountcheck_volumes(struct hammer_mount
*hmp
)
494 for (i
= 0; i
< hmp
->nvolumes
; ++i
) {
495 vol
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, i
);
502 /************************************************************************
504 ************************************************************************
506 * Manage buffers. Currently all blockmap-backed zones are translated
507 * to zone-2 buffer offsets.
510 hammer_get_buffer(hammer_mount_t hmp
, hammer_off_t buf_offset
,
511 int bytes
, int isnew
, int *errorp
)
513 hammer_buffer_t buffer
;
514 hammer_volume_t volume
;
515 hammer_off_t zone2_offset
;
516 hammer_io_type_t iotype
;
520 buf_offset
&= ~HAMMER_BUFMASK64
;
523 * Shortcut if the buffer is already cached
525 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buf_offset
);
527 if (buffer
->io
.lock
.refs
== 0)
528 ++hammer_count_refedbufs
;
529 hammer_ref(&buffer
->io
.lock
);
532 * Once refed the ondisk field will not be cleared by
535 if (buffer
->ondisk
&& buffer
->io
.loading
== 0) {
541 * The buffer is no longer loose if it has a ref, and
542 * cannot become loose once it gains a ref. Loose
543 * buffers will never be in a modified state. This should
544 * only occur on the 0->1 transition of refs.
546 * lose_list can be modified via a biodone() interrupt.
548 if (buffer
->io
.mod_list
== &hmp
->lose_list
) {
549 crit_enter(); /* biodone race against list */
550 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
,
553 buffer
->io
.mod_list
= NULL
;
554 KKASSERT(buffer
->io
.modified
== 0);
560 * What is the buffer class?
562 zone
= HAMMER_ZONE_DECODE(buf_offset
);
565 case HAMMER_ZONE_LARGE_DATA_INDEX
:
566 case HAMMER_ZONE_SMALL_DATA_INDEX
:
567 iotype
= HAMMER_STRUCTURE_DATA_BUFFER
;
569 case HAMMER_ZONE_UNDO_INDEX
:
570 iotype
= HAMMER_STRUCTURE_UNDO_BUFFER
;
572 case HAMMER_ZONE_META_INDEX
:
575 * NOTE: inode data and directory entries are placed in this
576 * zone. inode atime/mtime is updated in-place and thus
577 * buffers containing inodes must be synchronized as
578 * meta-buffers, same as buffers containing B-Tree info.
580 iotype
= HAMMER_STRUCTURE_META_BUFFER
;
585 * Handle blockmap offset translations
587 if (zone
>= HAMMER_ZONE_BTREE_INDEX
) {
588 zone2_offset
= hammer_blockmap_lookup(hmp
, buf_offset
, errorp
);
589 } else if (zone
== HAMMER_ZONE_UNDO_INDEX
) {
590 zone2_offset
= hammer_undo_lookup(hmp
, buf_offset
, errorp
);
592 KKASSERT(zone
== HAMMER_ZONE_RAW_BUFFER_INDEX
);
593 zone2_offset
= buf_offset
;
600 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset
603 KKASSERT((zone2_offset
& HAMMER_OFF_ZONE_MASK
) ==
604 HAMMER_ZONE_RAW_BUFFER
);
605 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
606 volume
= hammer_get_volume(hmp
, vol_no
, errorp
);
610 KKASSERT(zone2_offset
< volume
->maxbuf_off
);
613 * Allocate a new buffer structure. We will check for races later.
615 ++hammer_count_buffers
;
616 buffer
= kmalloc(sizeof(*buffer
), hmp
->m_misc
,
617 M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
618 buffer
->zone2_offset
= zone2_offset
;
619 buffer
->zoneX_offset
= buf_offset
;
621 hammer_io_init(&buffer
->io
, volume
, iotype
);
622 buffer
->io
.offset
= volume
->ondisk
->vol_buf_beg
+
623 (zone2_offset
& HAMMER_OFF_SHORT_MASK
);
624 buffer
->io
.bytes
= bytes
;
625 TAILQ_INIT(&buffer
->clist
);
626 hammer_ref(&buffer
->io
.lock
);
629 * Insert the buffer into the RB tree and handle late collisions.
631 if (RB_INSERT(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buffer
)) {
632 hammer_unref(&buffer
->io
.lock
);
633 --hammer_count_buffers
;
634 kfree(buffer
, hmp
->m_misc
);
637 ++hammer_count_refedbufs
;
641 * Deal with on-disk info and loading races.
643 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
644 *errorp
= hammer_load_buffer(buffer
, isnew
);
646 hammer_rel_buffer(buffer
, 1);
656 * This is used by the direct-read code to deal with large-data buffers
657 * created by the reblocker and mirror-write code. The direct-read code
658 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write-
659 * running hammer buffers must be fully synced to disk before we can issue
662 * This code path is not considered critical as only the rebocker and
663 * mirror-write code will create large-data buffers via the HAMMER buffer
664 * subsystem. They do that because they operate at the B-Tree level and
665 * do not access the vnode/inode structures.
668 hammer_sync_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
, int bytes
)
670 hammer_buffer_t buffer
;
673 KKASSERT((base_offset
& HAMMER_OFF_ZONE_MASK
) ==
674 HAMMER_ZONE_LARGE_DATA
);
677 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
679 if (buffer
&& (buffer
->io
.modified
|| buffer
->io
.running
)) {
680 error
= hammer_ref_buffer(buffer
);
682 hammer_io_wait(&buffer
->io
);
683 if (buffer
->io
.modified
) {
684 hammer_io_write_interlock(&buffer
->io
);
685 hammer_io_flush(&buffer
->io
);
686 hammer_io_done_interlock(&buffer
->io
);
687 hammer_io_wait(&buffer
->io
);
689 hammer_rel_buffer(buffer
, 0);
692 base_offset
+= HAMMER_BUFSIZE
;
693 bytes
-= HAMMER_BUFSIZE
;
698 * Destroy all buffers covering the specified zoneX offset range. This
699 * is called when the related blockmap layer2 entry is freed or when
700 * a direct write bypasses our buffer/buffer-cache subsystem.
702 * The buffers may be referenced by the caller itself. Setting reclaim
703 * will cause the buffer to be destroyed when it's ref count reaches zero.
706 hammer_del_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
,
707 hammer_off_t zone2_offset
, int bytes
)
709 hammer_buffer_t buffer
;
710 hammer_volume_t volume
;
714 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
715 volume
= hammer_get_volume(hmp
, vol_no
, &error
);
716 KKASSERT(error
== 0);
719 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
722 error
= hammer_ref_buffer(buffer
);
724 KKASSERT(buffer
->zone2_offset
== zone2_offset
);
725 hammer_io_clear_modify(&buffer
->io
, 1);
726 buffer
->io
.reclaim
= 1;
727 buffer
->io
.waitdep
= 1;
728 KKASSERT(buffer
->io
.volume
== volume
);
729 hammer_rel_buffer(buffer
, 0);
732 hammer_io_inval(volume
, zone2_offset
);
734 base_offset
+= HAMMER_BUFSIZE
;
735 zone2_offset
+= HAMMER_BUFSIZE
;
736 bytes
-= HAMMER_BUFSIZE
;
738 hammer_rel_volume(volume
, 0);
742 hammer_load_buffer(hammer_buffer_t buffer
, int isnew
)
744 hammer_volume_t volume
;
748 * Load the buffer's on-disk info
750 volume
= buffer
->io
.volume
;
751 ++buffer
->io
.loading
;
752 hammer_lock_ex(&buffer
->io
.lock
);
754 if (hammer_debug_io
& 0x0001) {
755 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n",
756 buffer
->zoneX_offset
, buffer
->zone2_offset
, isnew
,
760 if (buffer
->ondisk
== NULL
) {
762 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
764 error
= hammer_io_read(volume
->devvp
, &buffer
->io
,
768 buffer
->ondisk
= (void *)buffer
->io
.bp
->b_data
;
770 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
774 --buffer
->io
.loading
;
775 hammer_unlock(&buffer
->io
.lock
);
780 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue.
781 * This routine is only called during unmount.
784 hammer_unload_buffer(hammer_buffer_t buffer
, void *data __unused
)
787 * Clean up the persistent ref ioerror might have on the buffer
788 * and acquire a ref (steal ioerror's if we can).
790 if (buffer
->io
.ioerror
) {
791 buffer
->io
.ioerror
= 0;
793 if (buffer
->io
.lock
.refs
== 0)
794 ++hammer_count_refedbufs
;
795 hammer_ref(&buffer
->io
.lock
);
799 * We must not flush a dirty buffer to disk on umount. It should
800 * have already been dealt with by the flusher, or we may be in
801 * catastrophic failure.
803 hammer_io_clear_modify(&buffer
->io
, 1);
804 hammer_flush_buffer_nodes(buffer
);
805 KKASSERT(buffer
->io
.lock
.refs
== 1);
806 hammer_rel_buffer(buffer
, 2);
811 * Reference a buffer that is either already referenced or via a specially
812 * handled pointer (aka cursor->buffer).
815 hammer_ref_buffer(hammer_buffer_t buffer
)
819 if (buffer
->io
.lock
.refs
== 0)
820 ++hammer_count_refedbufs
;
821 hammer_ref(&buffer
->io
.lock
);
824 * At this point a biodone() will not touch the buffer other then
825 * incidental bits. However, lose_list can be modified via
826 * a biodone() interrupt.
830 if (buffer
->io
.mod_list
== &buffer
->io
.hmp
->lose_list
) {
832 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
, mod_entry
);
833 buffer
->io
.mod_list
= NULL
;
837 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
838 error
= hammer_load_buffer(buffer
, 0);
840 hammer_rel_buffer(buffer
, 1);
842 * NOTE: buffer pointer can become stale after
853 * Release a buffer. We have to deal with several places where
854 * another thread can ref the buffer.
856 * Only destroy the structure itself if the related buffer cache buffer
857 * was disassociated from it. This ties the management of the structure
858 * to the buffer cache subsystem. buffer->ondisk determines whether the
859 * embedded io is referenced or not.
862 hammer_rel_buffer(hammer_buffer_t buffer
, int flush
)
864 hammer_volume_t volume
;
866 struct buf
*bp
= NULL
;
869 hmp
= buffer
->io
.hmp
;
872 if (buffer
->io
.lock
.refs
== 1) {
873 ++buffer
->io
.loading
; /* force interlock check */
874 hammer_lock_ex(&buffer
->io
.lock
);
875 if (buffer
->io
.lock
.refs
== 1) {
876 bp
= hammer_io_release(&buffer
->io
, flush
);
878 if (buffer
->io
.lock
.refs
== 1)
879 --hammer_count_refedbufs
;
881 if (buffer
->io
.bp
== NULL
&&
882 buffer
->io
.lock
.refs
== 1) {
886 * NOTE: It is impossible for any associated
887 * B-Tree nodes to have refs if the buffer
888 * has no additional refs.
890 RB_REMOVE(hammer_buf_rb_tree
,
891 &buffer
->io
.hmp
->rb_bufs_root
,
893 volume
= buffer
->io
.volume
;
894 buffer
->io
.volume
= NULL
; /* sanity */
895 hammer_rel_volume(volume
, 0);
896 hammer_io_clear_modlist(&buffer
->io
);
897 hammer_flush_buffer_nodes(buffer
);
898 KKASSERT(TAILQ_EMPTY(&buffer
->clist
));
902 --buffer
->io
.loading
;
903 hammer_unlock(&buffer
->io
.lock
);
905 hammer_unref(&buffer
->io
.lock
);
910 --hammer_count_buffers
;
911 kfree(buffer
, hmp
->m_misc
);
916 * Access the filesystem buffer containing the specified hammer offset.
917 * buf_offset is a conglomeration of the volume number and vol_buf_beg
918 * relative buffer offset. It must also have bit 55 set to be valid.
919 * (see hammer_off_t in hammer_disk.h).
921 * Any prior buffer in *bufferp will be released and replaced by the
926 _hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
927 int *errorp
, struct hammer_buffer
**bufferp
)
929 hammer_buffer_t buffer
;
930 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
932 buf_offset
&= ~HAMMER_BUFMASK64
;
933 KKASSERT((buf_offset
& HAMMER_OFF_ZONE_MASK
) != 0);
936 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
937 buffer
->zoneX_offset
!= buf_offset
)) {
939 hammer_rel_buffer(buffer
, 0);
940 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 0, errorp
);
947 * Return a pointer to the buffer data.
952 return((char *)buffer
->ondisk
+ xoff
);
956 hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
,
957 int *errorp
, struct hammer_buffer
**bufferp
)
959 return(_hammer_bread(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
963 hammer_bread_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
964 int *errorp
, struct hammer_buffer
**bufferp
)
966 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
967 return(_hammer_bread(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
971 * Access the filesystem buffer containing the specified hammer offset.
972 * No disk read operation occurs. The result buffer may contain garbage.
974 * Any prior buffer in *bufferp will be released and replaced by the
977 * This function marks the buffer dirty but does not increment its
982 _hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
983 int *errorp
, struct hammer_buffer
**bufferp
)
985 hammer_buffer_t buffer
;
986 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
988 buf_offset
&= ~HAMMER_BUFMASK64
;
991 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
992 buffer
->zoneX_offset
!= buf_offset
)) {
994 hammer_rel_buffer(buffer
, 0);
995 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 1, errorp
);
1002 * Return a pointer to the buffer data.
1007 return((char *)buffer
->ondisk
+ xoff
);
1011 hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
,
1012 int *errorp
, struct hammer_buffer
**bufferp
)
1014 return(_hammer_bnew(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
1018 hammer_bnew_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
1019 int *errorp
, struct hammer_buffer
**bufferp
)
1021 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
1022 return(_hammer_bnew(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
1025 /************************************************************************
1027 ************************************************************************
1029 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing
1030 * method used by the HAMMER filesystem.
1032 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY
1033 * associated with its buffer, and will only referenced the buffer while
1034 * the node itself is referenced.
1036 * A hammer_node can also be passively associated with other HAMMER
1037 * structures, such as inodes, while retaining 0 references. These
1038 * associations can be cleared backwards using a pointer-to-pointer in
1041 * This allows the HAMMER implementation to cache hammer_nodes long-term
1042 * and short-cut a great deal of the infrastructure's complexity. In
1043 * most cases a cached node can be reacquired without having to dip into
1044 * either the buffer or cluster management code.
1046 * The caller must pass a referenced cluster on call and will retain
1047 * ownership of the reference on return. The node will acquire its own
1048 * additional references, if necessary.
1051 hammer_get_node(hammer_mount_t hmp
, hammer_off_t node_offset
,
1052 int isnew
, int *errorp
)
1056 KKASSERT((node_offset
& HAMMER_OFF_ZONE_MASK
) == HAMMER_ZONE_BTREE
);
1059 * Locate the structure, allocating one if necessary.
1062 node
= RB_LOOKUP(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node_offset
);
1064 ++hammer_count_nodes
;
1065 node
= kmalloc(sizeof(*node
), hmp
->m_misc
, M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
1066 node
->node_offset
= node_offset
;
1068 TAILQ_INIT(&node
->cursor_list
);
1069 TAILQ_INIT(&node
->cache_list
);
1070 if (RB_INSERT(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node
)) {
1071 --hammer_count_nodes
;
1072 kfree(node
, hmp
->m_misc
);
1076 hammer_ref(&node
->lock
);
1080 *errorp
= hammer_load_node(node
, isnew
);
1082 hammer_rel_node(node
);
1089 * Reference an already-referenced node.
1092 hammer_ref_node(hammer_node_t node
)
1094 KKASSERT(node
->lock
.refs
> 0 && node
->ondisk
!= NULL
);
1095 hammer_ref(&node
->lock
);
1099 * Load a node's on-disk data reference.
1102 hammer_load_node(hammer_node_t node
, int isnew
)
1104 hammer_buffer_t buffer
;
1105 hammer_off_t buf_offset
;
1110 hammer_lock_ex(&node
->lock
);
1111 if (node
->ondisk
== NULL
) {
1113 * This is a little confusing but the jist is that
1114 * node->buffer determines whether the node is on
1115 * the buffer's clist and node->ondisk determines
1116 * whether the buffer is referenced.
1118 * We could be racing a buffer release, in which case
1119 * node->buffer may become NULL while we are blocked
1120 * referencing the buffer.
1122 if ((buffer
= node
->buffer
) != NULL
) {
1123 error
= hammer_ref_buffer(buffer
);
1124 if (error
== 0 && node
->buffer
== NULL
) {
1125 TAILQ_INSERT_TAIL(&buffer
->clist
,
1127 node
->buffer
= buffer
;
1130 buf_offset
= node
->node_offset
& ~HAMMER_BUFMASK64
;
1131 buffer
= hammer_get_buffer(node
->hmp
, buf_offset
,
1132 HAMMER_BUFSIZE
, 0, &error
);
1134 KKASSERT(error
== 0);
1135 TAILQ_INSERT_TAIL(&buffer
->clist
,
1137 node
->buffer
= buffer
;
1142 node
->ondisk
= (void *)((char *)buffer
->ondisk
+
1143 (node
->node_offset
& HAMMER_BUFMASK
));
1145 (node
->flags
& HAMMER_NODE_CRCGOOD
) == 0) {
1146 if (hammer_crc_test_btree(node
->ondisk
) == 0)
1147 Debugger("CRC FAILED: B-TREE NODE");
1148 node
->flags
|= HAMMER_NODE_CRCGOOD
;
1153 hammer_unlock(&node
->lock
);
1158 * Safely reference a node, interlock against flushes via the IO subsystem.
1161 hammer_ref_node_safe(struct hammer_mount
*hmp
, hammer_node_cache_t cache
,
1168 hammer_ref(&node
->lock
);
1172 *errorp
= hammer_load_node(node
, 0);
1174 hammer_rel_node(node
);
1184 * Release a hammer_node. On the last release the node dereferences
1185 * its underlying buffer and may or may not be destroyed.
1188 hammer_rel_node(hammer_node_t node
)
1190 hammer_buffer_t buffer
;
1193 * If this isn't the last ref just decrement the ref count and
1196 if (node
->lock
.refs
> 1) {
1197 hammer_unref(&node
->lock
);
1202 * If there is no ondisk info or no buffer the node failed to load,
1203 * remove the last reference and destroy the node.
1205 if (node
->ondisk
== NULL
) {
1206 hammer_unref(&node
->lock
);
1207 hammer_flush_node(node
);
1208 /* node is stale now */
1213 * Do not disassociate the node from the buffer if it represents
1214 * a modified B-Tree node that still needs its crc to be generated.
1216 if (node
->flags
& HAMMER_NODE_NEEDSCRC
)
1220 * Do final cleanups and then either destroy the node and leave it
1221 * passively cached. The buffer reference is removed regardless.
1223 buffer
= node
->buffer
;
1224 node
->ondisk
= NULL
;
1226 if ((node
->flags
& HAMMER_NODE_FLUSH
) == 0) {
1227 hammer_unref(&node
->lock
);
1228 hammer_rel_buffer(buffer
, 0);
1235 hammer_unref(&node
->lock
);
1236 hammer_flush_node(node
);
1238 hammer_rel_buffer(buffer
, 0);
1242 * Free space on-media associated with a B-Tree node.
1245 hammer_delete_node(hammer_transaction_t trans
, hammer_node_t node
)
1247 KKASSERT((node
->flags
& HAMMER_NODE_DELETED
) == 0);
1248 node
->flags
|= HAMMER_NODE_DELETED
;
1249 hammer_blockmap_free(trans
, node
->node_offset
, sizeof(*node
->ondisk
));
1253 * Passively cache a referenced hammer_node. The caller may release
1254 * the node on return.
1257 hammer_cache_node(hammer_node_cache_t cache
, hammer_node_t node
)
1260 * If the node doesn't exist, or is being deleted, don't cache it!
1262 * The node can only ever be NULL in the I/O failure path.
1264 if (node
== NULL
|| (node
->flags
& HAMMER_NODE_DELETED
))
1266 if (cache
->node
== node
)
1269 hammer_uncache_node(cache
);
1270 if (node
->flags
& HAMMER_NODE_DELETED
)
1273 TAILQ_INSERT_TAIL(&node
->cache_list
, cache
, entry
);
1277 hammer_uncache_node(hammer_node_cache_t cache
)
1281 if ((node
= cache
->node
) != NULL
) {
1282 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1284 if (TAILQ_EMPTY(&node
->cache_list
))
1285 hammer_flush_node(node
);
1290 * Remove a node's cache references and destroy the node if it has no
1291 * other references or backing store.
1294 hammer_flush_node(hammer_node_t node
)
1296 hammer_node_cache_t cache
;
1297 hammer_buffer_t buffer
;
1298 hammer_mount_t hmp
= node
->hmp
;
1300 while ((cache
= TAILQ_FIRST(&node
->cache_list
)) != NULL
) {
1301 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1304 if (node
->lock
.refs
== 0 && node
->ondisk
== NULL
) {
1305 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1306 RB_REMOVE(hammer_nod_rb_tree
, &node
->hmp
->rb_nods_root
, node
);
1307 if ((buffer
= node
->buffer
) != NULL
) {
1308 node
->buffer
= NULL
;
1309 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1310 /* buffer is unreferenced because ondisk is NULL */
1312 --hammer_count_nodes
;
1313 kfree(node
, hmp
->m_misc
);
1318 * Flush passively cached B-Tree nodes associated with this buffer.
1319 * This is only called when the buffer is about to be destroyed, so
1320 * none of the nodes should have any references. The buffer is locked.
1322 * We may be interlocked with the buffer.
1325 hammer_flush_buffer_nodes(hammer_buffer_t buffer
)
1329 while ((node
= TAILQ_FIRST(&buffer
->clist
)) != NULL
) {
1330 KKASSERT(node
->ondisk
== NULL
);
1331 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1333 if (node
->lock
.refs
== 0) {
1334 hammer_ref(&node
->lock
);
1335 node
->flags
|= HAMMER_NODE_FLUSH
;
1336 hammer_rel_node(node
);
1338 KKASSERT(node
->loading
!= 0);
1339 KKASSERT(node
->buffer
!= NULL
);
1340 buffer
= node
->buffer
;
1341 node
->buffer
= NULL
;
1342 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1343 /* buffer is unreferenced because ondisk is NULL */
1349 /************************************************************************
1351 ************************************************************************/
1354 * Allocate a B-Tree node.
1357 hammer_alloc_btree(hammer_transaction_t trans
, int *errorp
)
1359 hammer_buffer_t buffer
= NULL
;
1360 hammer_node_t node
= NULL
;
1361 hammer_off_t node_offset
;
1363 node_offset
= hammer_blockmap_alloc(trans
, HAMMER_ZONE_BTREE_INDEX
,
1364 sizeof(struct hammer_node_ondisk
),
1367 node
= hammer_get_node(trans
->hmp
, node_offset
, 1, errorp
);
1368 hammer_modify_node_noundo(trans
, node
);
1369 bzero(node
->ondisk
, sizeof(*node
->ondisk
));
1370 hammer_modify_node_done(node
);
1373 hammer_rel_buffer(buffer
, 0);
1378 * Allocate data. If the address of a data buffer is supplied then
1379 * any prior non-NULL *data_bufferp will be released and *data_bufferp
1380 * will be set to the related buffer. The caller must release it when
1381 * finally done. The initial *data_bufferp should be set to NULL by
1384 * The caller is responsible for making hammer_modify*() calls on the
1388 hammer_alloc_data(hammer_transaction_t trans
, int32_t data_len
,
1389 u_int16_t rec_type
, hammer_off_t
*data_offsetp
,
1390 struct hammer_buffer
**data_bufferp
, int *errorp
)
1400 case HAMMER_RECTYPE_INODE
:
1401 case HAMMER_RECTYPE_DIRENTRY
:
1402 case HAMMER_RECTYPE_EXT
:
1403 case HAMMER_RECTYPE_FIX
:
1404 case HAMMER_RECTYPE_PFS
:
1405 zone
= HAMMER_ZONE_META_INDEX
;
1407 case HAMMER_RECTYPE_DATA
:
1408 case HAMMER_RECTYPE_DB
:
1409 if (data_len
<= HAMMER_BUFSIZE
/ 2) {
1410 zone
= HAMMER_ZONE_SMALL_DATA_INDEX
;
1412 data_len
= (data_len
+ HAMMER_BUFMASK
) &
1414 zone
= HAMMER_ZONE_LARGE_DATA_INDEX
;
1418 panic("hammer_alloc_data: rec_type %04x unknown",
1420 zone
= 0; /* NOT REACHED */
1423 *data_offsetp
= hammer_blockmap_alloc(trans
, zone
,
1428 if (*errorp
== 0 && data_bufferp
) {
1430 data
= hammer_bread_ext(trans
->hmp
, *data_offsetp
,
1431 data_len
, errorp
, data_bufferp
);
1442 * Sync dirty buffers to the media and clean-up any loose ends.
1444 * These functions do not start the flusher going, they simply
1445 * queue everything up to the flusher.
1447 static int hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
);
1448 static int hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
);
1451 hammer_queue_inodes_flusher(hammer_mount_t hmp
, int waitfor
)
1453 struct hammer_sync_info info
;
1456 info
.waitfor
= waitfor
;
1457 if (waitfor
== MNT_WAIT
) {
1458 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
,
1459 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1461 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
|VMSC_NOWAIT
,
1462 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1468 * Filesystem sync. If doing a synchronous sync make a second pass on
1469 * the vnodes in case any were already flushing during the first pass,
1470 * and activate the flusher twice (the second time brings the UNDO FIFO's
1471 * start position up to the end position after the first call).
1474 hammer_sync_hmp(hammer_mount_t hmp
, int waitfor
)
1476 struct hammer_sync_info info
;
1479 info
.waitfor
= MNT_NOWAIT
;
1480 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_NOWAIT
,
1481 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1482 if (info
.error
== 0 && waitfor
== MNT_WAIT
) {
1483 info
.waitfor
= waitfor
;
1484 vmntvnodescan(hmp
->mp
, VMSC_GETVP
,
1485 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1487 if (waitfor
== MNT_WAIT
) {
1488 hammer_flusher_sync(hmp
);
1489 hammer_flusher_sync(hmp
);
1491 hammer_flusher_async(hmp
, NULL
);
1492 hammer_flusher_async(hmp
, NULL
);
1498 hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
)
1500 struct hammer_inode
*ip
;
1503 if (vp
->v_type
== VNON
|| ip
== NULL
||
1504 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1505 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1512 hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
)
1514 struct hammer_sync_info
*info
= data
;
1515 struct hammer_inode
*ip
;
1519 if (vp
->v_type
== VNON
|| vp
->v_type
== VBAD
||
1520 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1521 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1524 error
= VOP_FSYNC(vp
, MNT_NOWAIT
);
1526 info
->error
= error
;