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 1.69.2.2 2008/07/18 00:21:09 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
)
104 hammer_volume_t volume
;
105 struct hammer_volume_ondisk
*ondisk
;
106 struct nlookupdata nd
;
107 struct buf
*bp
= NULL
;
113 ronly
= ((mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
116 * Allocate a volume structure
118 ++hammer_count_volumes
;
119 volume
= kmalloc(sizeof(*volume
), M_HAMMER
, M_WAITOK
|M_ZERO
);
120 volume
->vol_name
= kstrdup(volname
, M_HAMMER
);
121 hammer_io_init(&volume
->io
, hmp
, HAMMER_STRUCTURE_VOLUME
);
122 volume
->io
.offset
= 0LL;
123 volume
->io
.bytes
= HAMMER_BUFSIZE
;
126 * Get the device vnode
128 error
= nlookup_init(&nd
, volume
->vol_name
, UIO_SYSSPACE
, NLC_FOLLOW
);
130 error
= nlookup(&nd
);
132 error
= cache_vref(&nd
.nl_nch
, nd
.nl_cred
, &volume
->devvp
);
135 if (vn_isdisk(volume
->devvp
, &error
)) {
136 error
= vfs_mountedon(volume
->devvp
);
140 count_udev(volume
->devvp
->v_umajor
, volume
->devvp
->v_uminor
) > 0) {
144 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
145 error
= vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
147 error
= VOP_OPEN(volume
->devvp
,
148 (ronly
? FREAD
: FREAD
|FWRITE
),
151 vn_unlock(volume
->devvp
);
154 hammer_free_volume(volume
);
157 volume
->devvp
->v_rdev
->si_mountpoint
= mp
;
161 * Extract the volume number from the volume header and do various
164 error
= bread(volume
->devvp
, 0LL, HAMMER_BUFSIZE
, &bp
);
167 ondisk
= (void *)bp
->b_data
;
168 if (ondisk
->vol_signature
!= HAMMER_FSBUF_VOLUME
) {
169 kprintf("hammer_mount: volume %s has an invalid header\n",
174 volume
->vol_no
= ondisk
->vol_no
;
175 volume
->buffer_base
= ondisk
->vol_buf_beg
;
176 volume
->vol_flags
= ondisk
->vol_flags
;
177 volume
->nblocks
= ondisk
->vol_nblocks
;
178 volume
->maxbuf_off
= HAMMER_ENCODE_RAW_BUFFER(volume
->vol_no
,
179 ondisk
->vol_buf_end
- ondisk
->vol_buf_beg
);
180 volume
->maxraw_off
= ondisk
->vol_buf_end
;
182 if (RB_EMPTY(&hmp
->rb_vols_root
)) {
183 hmp
->fsid
= ondisk
->vol_fsid
;
184 } else if (bcmp(&hmp
->fsid
, &ondisk
->vol_fsid
, sizeof(uuid_t
))) {
185 kprintf("hammer_mount: volume %s's fsid does not match "
186 "other volumes\n", volume
->vol_name
);
192 * Insert the volume structure into the red-black tree.
194 if (RB_INSERT(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
)) {
195 kprintf("hammer_mount: volume %s has a duplicate vol_no %d\n",
196 volume
->vol_name
, volume
->vol_no
);
201 * Set the root volume . HAMMER special cases rootvol the structure.
202 * We do not hold a ref because this would prevent related I/O
203 * from being flushed.
205 if (error
== 0 && ondisk
->vol_rootvol
== ondisk
->vol_no
) {
206 hmp
->rootvol
= volume
;
207 hmp
->nvolumes
= ondisk
->vol_count
;
212 hmp
->mp
->mnt_stat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
213 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
214 hmp
->mp
->mnt_vstat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
215 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
221 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/
223 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
224 VOP_CLOSE(volume
->devvp
, ronly
? FREAD
: FREAD
|FWRITE
);
225 hammer_free_volume(volume
);
231 * This is called for each volume when updating the mount point from
232 * read-write to read-only or vise-versa.
235 hammer_adjust_volume_mode(hammer_volume_t volume
, void *data __unused
)
238 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
239 if (volume
->io
.hmp
->ronly
) {
240 /* do not call vinvalbuf */
241 VOP_OPEN(volume
->devvp
, FREAD
, FSCRED
, NULL
);
242 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
244 /* do not call vinvalbuf */
245 VOP_OPEN(volume
->devvp
, FREAD
|FWRITE
, FSCRED
, NULL
);
246 VOP_CLOSE(volume
->devvp
, FREAD
);
248 vn_unlock(volume
->devvp
);
254 * Unload and free a HAMMER volume. Must return >= 0 to continue scan
255 * so returns -1 on failure.
258 hammer_unload_volume(hammer_volume_t volume
, void *data __unused
)
260 struct hammer_mount
*hmp
= volume
->io
.hmp
;
261 int ronly
= ((hmp
->mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
265 * Clean up the root volume pointer, which is held unlocked in hmp.
267 if (hmp
->rootvol
== volume
)
271 * We must not flush a dirty buffer to disk on umount. It should
272 * have already been dealt with by the flusher, or we may be in
273 * catastrophic failure.
275 hammer_io_clear_modify(&volume
->io
, 1);
276 volume
->io
.waitdep
= 1;
277 bp
= hammer_io_release(&volume
->io
, 1);
280 * Clean up the persistent ref ioerror might have on the volume
282 if (volume
->io
.ioerror
) {
283 volume
->io
.ioerror
= 0;
284 hammer_unref(&volume
->io
.lock
);
288 * There should be no references on the volume, no clusters, and
291 KKASSERT(volume
->io
.lock
.refs
== 0);
295 volume
->ondisk
= NULL
;
297 if (volume
->devvp
->v_rdev
&&
298 volume
->devvp
->v_rdev
->si_mountpoint
== hmp
->mp
300 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
304 * Make sure we don't sync anything to disk if we
305 * are in read-only mode (1) or critically-errored
306 * (2). Note that there may be dirty buffers in
307 * normal read-only mode from crash recovery.
309 vinvalbuf(volume
->devvp
, 0, 0, 0);
310 VOP_CLOSE(volume
->devvp
, FREAD
);
313 * Normal termination, save any dirty buffers
314 * (XXX there really shouldn't be any).
316 vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
317 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
322 * Destroy the structure
324 RB_REMOVE(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
);
325 hammer_free_volume(volume
);
331 hammer_free_volume(hammer_volume_t volume
)
333 if (volume
->vol_name
) {
334 kfree(volume
->vol_name
, M_HAMMER
);
335 volume
->vol_name
= NULL
;
338 vrele(volume
->devvp
);
339 volume
->devvp
= NULL
;
341 --hammer_count_volumes
;
342 kfree(volume
, M_HAMMER
);
346 * Get a HAMMER volume. The volume must already exist.
349 hammer_get_volume(struct hammer_mount
*hmp
, int32_t vol_no
, int *errorp
)
351 struct hammer_volume
*volume
;
354 * Locate the volume structure
356 volume
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, vol_no
);
357 if (volume
== NULL
) {
361 hammer_ref(&volume
->io
.lock
);
364 * Deal with on-disk info
366 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
367 *errorp
= hammer_load_volume(volume
);
369 hammer_rel_volume(volume
, 1);
379 hammer_ref_volume(hammer_volume_t volume
)
383 hammer_ref(&volume
->io
.lock
);
386 * Deal with on-disk info
388 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
389 error
= hammer_load_volume(volume
);
391 hammer_rel_volume(volume
, 1);
399 hammer_get_root_volume(struct hammer_mount
*hmp
, int *errorp
)
401 hammer_volume_t volume
;
403 volume
= hmp
->rootvol
;
404 KKASSERT(volume
!= NULL
);
405 hammer_ref(&volume
->io
.lock
);
408 * Deal with on-disk info
410 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
411 *errorp
= hammer_load_volume(volume
);
413 hammer_rel_volume(volume
, 1);
423 * Load a volume's on-disk information. The volume must be referenced and
424 * not locked. We temporarily acquire an exclusive lock to interlock
425 * against releases or multiple get's.
428 hammer_load_volume(hammer_volume_t volume
)
432 ++volume
->io
.loading
;
433 hammer_lock_ex(&volume
->io
.lock
);
435 if (volume
->ondisk
== NULL
) {
436 error
= hammer_io_read(volume
->devvp
, &volume
->io
,
439 volume
->ondisk
= (void *)volume
->io
.bp
->b_data
;
443 --volume
->io
.loading
;
444 hammer_unlock(&volume
->io
.lock
);
449 * Release a volume. Call hammer_io_release on the last reference. We have
450 * to acquire an exclusive lock to interlock against volume->ondisk tests
451 * in hammer_load_volume(), and hammer_io_release() also expects an exclusive
454 * Volumes are not unloaded from memory during normal operation.
457 hammer_rel_volume(hammer_volume_t volume
, int flush
)
459 struct buf
*bp
= NULL
;
462 if (volume
->io
.lock
.refs
== 1) {
463 ++volume
->io
.loading
;
464 hammer_lock_ex(&volume
->io
.lock
);
465 if (volume
->io
.lock
.refs
== 1) {
466 volume
->ondisk
= NULL
;
467 bp
= hammer_io_release(&volume
->io
, flush
);
469 --volume
->io
.loading
;
470 hammer_unlock(&volume
->io
.lock
);
472 hammer_unref(&volume
->io
.lock
);
479 hammer_mountcheck_volumes(struct hammer_mount
*hmp
)
484 for (i
= 0; i
< hmp
->nvolumes
; ++i
) {
485 vol
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, i
);
492 /************************************************************************
494 ************************************************************************
496 * Manage buffers. Currently all blockmap-backed zones are translated
497 * to zone-2 buffer offsets.
500 hammer_get_buffer(hammer_mount_t hmp
, hammer_off_t buf_offset
,
501 int bytes
, int isnew
, int *errorp
)
503 hammer_buffer_t buffer
;
504 hammer_volume_t volume
;
505 hammer_off_t zone2_offset
;
506 hammer_io_type_t iotype
;
510 buf_offset
&= ~HAMMER_BUFMASK64
;
513 * Shortcut if the buffer is already cached
515 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buf_offset
);
517 if (buffer
->io
.lock
.refs
== 0)
518 ++hammer_count_refedbufs
;
519 hammer_ref(&buffer
->io
.lock
);
522 * Onced refed the ondisk field will not be cleared by
525 if (buffer
->ondisk
&& buffer
->io
.loading
== 0) {
531 * The buffer is no longer loose if it has a ref, and
532 * cannot become loose once it gains a ref. Loose
533 * buffers will never be in a modified state. This should
534 * only occur on the 0->1 transition of refs.
536 * lose_list can be modified via a biodone() interrupt.
538 if (buffer
->io
.mod_list
== &hmp
->lose_list
) {
539 crit_enter(); /* biodone race against list */
540 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
,
543 buffer
->io
.mod_list
= NULL
;
544 KKASSERT(buffer
->io
.modified
== 0);
550 * What is the buffer class?
552 zone
= HAMMER_ZONE_DECODE(buf_offset
);
555 case HAMMER_ZONE_LARGE_DATA_INDEX
:
556 case HAMMER_ZONE_SMALL_DATA_INDEX
:
557 iotype
= HAMMER_STRUCTURE_DATA_BUFFER
;
559 case HAMMER_ZONE_UNDO_INDEX
:
560 iotype
= HAMMER_STRUCTURE_UNDO_BUFFER
;
562 case HAMMER_ZONE_META_INDEX
:
565 * NOTE: inode data and directory entries are placed in this
566 * zone. inode atime/mtime is updated in-place and thus
567 * buffers containing inodes must be synchronized as
568 * meta-buffers, same as buffers containing B-Tree info.
570 iotype
= HAMMER_STRUCTURE_META_BUFFER
;
575 * Handle blockmap offset translations
577 if (zone
>= HAMMER_ZONE_BTREE_INDEX
) {
578 zone2_offset
= hammer_blockmap_lookup(hmp
, buf_offset
, errorp
);
579 } else if (zone
== HAMMER_ZONE_UNDO_INDEX
) {
580 zone2_offset
= hammer_undo_lookup(hmp
, buf_offset
, errorp
);
582 KKASSERT(zone
== HAMMER_ZONE_RAW_BUFFER_INDEX
);
583 zone2_offset
= buf_offset
;
590 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset
593 KKASSERT((zone2_offset
& HAMMER_OFF_ZONE_MASK
) ==
594 HAMMER_ZONE_RAW_BUFFER
);
595 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
596 volume
= hammer_get_volume(hmp
, vol_no
, errorp
);
600 KKASSERT(zone2_offset
< volume
->maxbuf_off
);
603 * Allocate a new buffer structure. We will check for races later.
605 ++hammer_count_buffers
;
606 buffer
= kmalloc(sizeof(*buffer
), M_HAMMER
,
607 M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
608 buffer
->zone2_offset
= zone2_offset
;
609 buffer
->zoneX_offset
= buf_offset
;
610 buffer
->volume
= volume
;
612 hammer_io_init(&buffer
->io
, hmp
, iotype
);
613 buffer
->io
.offset
= volume
->ondisk
->vol_buf_beg
+
614 (zone2_offset
& HAMMER_OFF_SHORT_MASK
);
615 buffer
->io
.bytes
= bytes
;
616 TAILQ_INIT(&buffer
->clist
);
617 hammer_ref(&buffer
->io
.lock
);
620 * Insert the buffer into the RB tree and handle late collisions.
622 if (RB_INSERT(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buffer
)) {
623 hammer_unref(&buffer
->io
.lock
);
624 --hammer_count_buffers
;
625 kfree(buffer
, M_HAMMER
);
628 ++hammer_count_refedbufs
;
632 * Deal with on-disk info and loading races.
634 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
635 *errorp
= hammer_load_buffer(buffer
, isnew
);
637 hammer_rel_buffer(buffer
, 1);
647 * This is used by the direct-read code to deal with large-data buffers
648 * created by the reblocker and mirror-write code. The direct-read code
649 * bypasses the HAMMER buffer subsystem and so any aliased dirty hammer
650 * buffers must be fully synced to disk before we can issue the direct-read.
652 * This code path is not considered critical as only the rebocker and
653 * mirror-write code will create large-data buffers via the HAMMER buffer
654 * subsystem. They do that because they operate at the B-Tree level and
655 * do not access the vnode/inode structures.
658 hammer_sync_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
, int bytes
)
660 hammer_buffer_t buffer
;
663 KKASSERT((base_offset
& HAMMER_OFF_ZONE_MASK
) ==
664 HAMMER_ZONE_LARGE_DATA
);
667 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
669 if (buffer
&& buffer
->io
.modified
) {
670 error
= hammer_ref_buffer(buffer
);
671 if (error
== 0 && buffer
->io
.modified
) {
672 hammer_io_write_interlock(&buffer
->io
);
673 hammer_io_flush(&buffer
->io
);
674 hammer_io_done_interlock(&buffer
->io
);
675 hammer_io_wait(&buffer
->io
);
676 hammer_rel_buffer(buffer
, 0);
679 base_offset
+= HAMMER_BUFSIZE
;
680 bytes
-= HAMMER_BUFSIZE
;
685 * Destroy all buffers covering the specified zoneX offset range. This
686 * is called when the related blockmap layer2 entry is freed or when
687 * a direct write bypasses our buffer/buffer-cache subsystem.
689 * The buffers may be referenced by the caller itself. Setting reclaim
690 * will cause the buffer to be destroyed when it's ref count reaches zero.
693 hammer_del_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
,
694 hammer_off_t zone2_offset
, int bytes
)
696 hammer_buffer_t buffer
;
697 hammer_volume_t volume
;
701 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
702 volume
= hammer_get_volume(hmp
, vol_no
, &error
);
703 KKASSERT(error
== 0);
706 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
709 error
= hammer_ref_buffer(buffer
);
711 KKASSERT(buffer
->zone2_offset
== zone2_offset
);
712 hammer_io_clear_modify(&buffer
->io
, 1);
713 buffer
->io
.reclaim
= 1;
714 KKASSERT(buffer
->volume
== volume
);
715 hammer_rel_buffer(buffer
, 0);
718 hammer_io_inval(volume
, zone2_offset
);
720 base_offset
+= HAMMER_BUFSIZE
;
721 zone2_offset
+= HAMMER_BUFSIZE
;
722 bytes
-= HAMMER_BUFSIZE
;
724 hammer_rel_volume(volume
, 0);
728 hammer_load_buffer(hammer_buffer_t buffer
, int isnew
)
730 hammer_volume_t volume
;
734 * Load the buffer's on-disk info
736 volume
= buffer
->volume
;
737 ++buffer
->io
.loading
;
738 hammer_lock_ex(&buffer
->io
.lock
);
740 if (hammer_debug_io
& 0x0001) {
741 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n",
742 buffer
->zoneX_offset
, buffer
->zone2_offset
, isnew
,
746 if (buffer
->ondisk
== NULL
) {
748 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
750 error
= hammer_io_read(volume
->devvp
, &buffer
->io
,
754 buffer
->ondisk
= (void *)buffer
->io
.bp
->b_data
;
756 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
760 --buffer
->io
.loading
;
761 hammer_unlock(&buffer
->io
.lock
);
766 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue.
767 * This routine is only called during unmount.
770 hammer_unload_buffer(hammer_buffer_t buffer
, void *data __unused
)
773 * Clean up the persistent ref ioerror might have on the buffer
774 * and acquire a ref (steal ioerror's if we can).
776 if (buffer
->io
.ioerror
) {
777 buffer
->io
.ioerror
= 0;
779 if (buffer
->io
.lock
.refs
== 0)
780 ++hammer_count_refedbufs
;
781 hammer_ref(&buffer
->io
.lock
);
785 * We must not flush a dirty buffer to disk on umount. It should
786 * have already been dealt with by the flusher, or we may be in
787 * catastrophic failure.
789 hammer_io_clear_modify(&buffer
->io
, 1);
790 hammer_flush_buffer_nodes(buffer
);
791 KKASSERT(buffer
->io
.lock
.refs
== 1);
792 hammer_rel_buffer(buffer
, 2);
797 * Reference a buffer that is either already referenced or via a specially
798 * handled pointer (aka cursor->buffer).
801 hammer_ref_buffer(hammer_buffer_t buffer
)
805 if (buffer
->io
.lock
.refs
== 0)
806 ++hammer_count_refedbufs
;
807 hammer_ref(&buffer
->io
.lock
);
810 * At this point a biodone() will not touch the buffer other then
811 * incidental bits. However, lose_list can be modified via
812 * a biodone() interrupt.
816 if (buffer
->io
.mod_list
== &buffer
->io
.hmp
->lose_list
) {
818 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
, mod_entry
);
819 buffer
->io
.mod_list
= NULL
;
823 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
824 error
= hammer_load_buffer(buffer
, 0);
826 hammer_rel_buffer(buffer
, 1);
828 * NOTE: buffer pointer can become stale after
839 * Release a buffer. We have to deal with several places where
840 * another thread can ref the buffer.
842 * Only destroy the structure itself if the related buffer cache buffer
843 * was disassociated from it. This ties the management of the structure
844 * to the buffer cache subsystem. buffer->ondisk determines whether the
845 * embedded io is referenced or not.
848 hammer_rel_buffer(hammer_buffer_t buffer
, int flush
)
850 hammer_volume_t volume
;
851 struct buf
*bp
= NULL
;
855 if (buffer
->io
.lock
.refs
== 1) {
856 ++buffer
->io
.loading
; /* force interlock check */
857 hammer_lock_ex(&buffer
->io
.lock
);
858 if (buffer
->io
.lock
.refs
== 1) {
859 bp
= hammer_io_release(&buffer
->io
, flush
);
861 if (buffer
->io
.lock
.refs
== 1)
862 --hammer_count_refedbufs
;
864 if (buffer
->io
.bp
== NULL
&&
865 buffer
->io
.lock
.refs
== 1) {
869 * NOTE: It is impossible for any associated
870 * B-Tree nodes to have refs if the buffer
871 * has no additional refs.
873 RB_REMOVE(hammer_buf_rb_tree
,
874 &buffer
->io
.hmp
->rb_bufs_root
,
876 volume
= buffer
->volume
;
877 buffer
->volume
= NULL
; /* sanity */
878 hammer_rel_volume(volume
, 0);
879 hammer_io_clear_modlist(&buffer
->io
);
880 hammer_flush_buffer_nodes(buffer
);
881 KKASSERT(TAILQ_EMPTY(&buffer
->clist
));
885 --buffer
->io
.loading
;
886 hammer_unlock(&buffer
->io
.lock
);
888 hammer_unref(&buffer
->io
.lock
);
893 --hammer_count_buffers
;
894 kfree(buffer
, M_HAMMER
);
899 * Access the filesystem buffer containing the specified hammer offset.
900 * buf_offset is a conglomeration of the volume number and vol_buf_beg
901 * relative buffer offset. It must also have bit 55 set to be valid.
902 * (see hammer_off_t in hammer_disk.h).
904 * Any prior buffer in *bufferp will be released and replaced by the
909 _hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
910 int *errorp
, struct hammer_buffer
**bufferp
)
912 hammer_buffer_t buffer
;
913 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
915 buf_offset
&= ~HAMMER_BUFMASK64
;
916 KKASSERT((buf_offset
& HAMMER_OFF_ZONE_MASK
) != 0);
919 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
920 buffer
->zoneX_offset
!= buf_offset
)) {
922 hammer_rel_buffer(buffer
, 0);
923 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 0, errorp
);
930 * Return a pointer to the buffer data.
935 return((char *)buffer
->ondisk
+ xoff
);
939 hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
,
940 int *errorp
, struct hammer_buffer
**bufferp
)
942 return(_hammer_bread(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
946 hammer_bread_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
947 int *errorp
, struct hammer_buffer
**bufferp
)
949 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
950 return(_hammer_bread(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
954 * Access the filesystem buffer containing the specified hammer offset.
955 * No disk read operation occurs. The result buffer may contain garbage.
957 * Any prior buffer in *bufferp will be released and replaced by the
960 * This function marks the buffer dirty but does not increment its
965 _hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
966 int *errorp
, struct hammer_buffer
**bufferp
)
968 hammer_buffer_t buffer
;
969 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
971 buf_offset
&= ~HAMMER_BUFMASK64
;
974 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
975 buffer
->zoneX_offset
!= buf_offset
)) {
977 hammer_rel_buffer(buffer
, 0);
978 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 1, errorp
);
985 * Return a pointer to the buffer data.
990 return((char *)buffer
->ondisk
+ xoff
);
994 hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
,
995 int *errorp
, struct hammer_buffer
**bufferp
)
997 return(_hammer_bnew(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
1001 hammer_bnew_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
1002 int *errorp
, struct hammer_buffer
**bufferp
)
1004 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
1005 return(_hammer_bnew(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
1008 /************************************************************************
1010 ************************************************************************
1012 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing
1013 * method used by the HAMMER filesystem.
1015 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY
1016 * associated with its buffer, and will only referenced the buffer while
1017 * the node itself is referenced.
1019 * A hammer_node can also be passively associated with other HAMMER
1020 * structures, such as inodes, while retaining 0 references. These
1021 * associations can be cleared backwards using a pointer-to-pointer in
1024 * This allows the HAMMER implementation to cache hammer_nodes long-term
1025 * and short-cut a great deal of the infrastructure's complexity. In
1026 * most cases a cached node can be reacquired without having to dip into
1027 * either the buffer or cluster management code.
1029 * The caller must pass a referenced cluster on call and will retain
1030 * ownership of the reference on return. The node will acquire its own
1031 * additional references, if necessary.
1034 hammer_get_node(hammer_mount_t hmp
, hammer_off_t node_offset
,
1035 int isnew
, int *errorp
)
1039 KKASSERT((node_offset
& HAMMER_OFF_ZONE_MASK
) == HAMMER_ZONE_BTREE
);
1042 * Locate the structure, allocating one if necessary.
1045 node
= RB_LOOKUP(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node_offset
);
1047 ++hammer_count_nodes
;
1048 node
= kmalloc(sizeof(*node
), M_HAMMER
, M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
1049 node
->node_offset
= node_offset
;
1051 TAILQ_INIT(&node
->cursor_list
);
1052 TAILQ_INIT(&node
->cache_list
);
1053 if (RB_INSERT(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node
)) {
1054 --hammer_count_nodes
;
1055 kfree(node
, M_HAMMER
);
1059 hammer_ref(&node
->lock
);
1063 *errorp
= hammer_load_node(node
, isnew
);
1065 hammer_rel_node(node
);
1072 * Reference an already-referenced node.
1075 hammer_ref_node(hammer_node_t node
)
1077 KKASSERT(node
->lock
.refs
> 0 && node
->ondisk
!= NULL
);
1078 hammer_ref(&node
->lock
);
1082 * Load a node's on-disk data reference.
1085 hammer_load_node(hammer_node_t node
, int isnew
)
1087 hammer_buffer_t buffer
;
1088 hammer_off_t buf_offset
;
1093 hammer_lock_ex(&node
->lock
);
1094 if (node
->ondisk
== NULL
) {
1096 * This is a little confusing but the jist is that
1097 * node->buffer determines whether the node is on
1098 * the buffer's clist and node->ondisk determines
1099 * whether the buffer is referenced.
1101 * We could be racing a buffer release, in which case
1102 * node->buffer may become NULL while we are blocked
1103 * referencing the buffer.
1105 if ((buffer
= node
->buffer
) != NULL
) {
1106 error
= hammer_ref_buffer(buffer
);
1107 if (error
== 0 && node
->buffer
== NULL
) {
1108 TAILQ_INSERT_TAIL(&buffer
->clist
,
1110 node
->buffer
= buffer
;
1113 buf_offset
= node
->node_offset
& ~HAMMER_BUFMASK64
;
1114 buffer
= hammer_get_buffer(node
->hmp
, buf_offset
,
1115 HAMMER_BUFSIZE
, 0, &error
);
1117 KKASSERT(error
== 0);
1118 TAILQ_INSERT_TAIL(&buffer
->clist
,
1120 node
->buffer
= buffer
;
1125 node
->ondisk
= (void *)((char *)buffer
->ondisk
+
1126 (node
->node_offset
& HAMMER_BUFMASK
));
1128 (node
->flags
& HAMMER_NODE_CRCGOOD
) == 0) {
1129 if (hammer_crc_test_btree(node
->ondisk
) == 0)
1130 Debugger("CRC FAILED: B-TREE NODE");
1131 node
->flags
|= HAMMER_NODE_CRCGOOD
;
1136 hammer_unlock(&node
->lock
);
1141 * Safely reference a node, interlock against flushes via the IO subsystem.
1144 hammer_ref_node_safe(struct hammer_mount
*hmp
, hammer_node_cache_t cache
,
1151 hammer_ref(&node
->lock
);
1155 *errorp
= hammer_load_node(node
, 0);
1157 hammer_rel_node(node
);
1167 * Release a hammer_node. On the last release the node dereferences
1168 * its underlying buffer and may or may not be destroyed.
1171 hammer_rel_node(hammer_node_t node
)
1173 hammer_buffer_t buffer
;
1176 * If this isn't the last ref just decrement the ref count and
1179 if (node
->lock
.refs
> 1) {
1180 hammer_unref(&node
->lock
);
1185 * If there is no ondisk info or no buffer the node failed to load,
1186 * remove the last reference and destroy the node.
1188 if (node
->ondisk
== NULL
) {
1189 hammer_unref(&node
->lock
);
1190 hammer_flush_node(node
);
1191 /* node is stale now */
1196 * Do not disassociate the node from the buffer if it represents
1197 * a modified B-Tree node that still needs its crc to be generated.
1199 if (node
->flags
& HAMMER_NODE_NEEDSCRC
)
1203 * Do final cleanups and then either destroy the node and leave it
1204 * passively cached. The buffer reference is removed regardless.
1206 buffer
= node
->buffer
;
1207 node
->ondisk
= NULL
;
1209 if ((node
->flags
& HAMMER_NODE_FLUSH
) == 0) {
1210 hammer_unref(&node
->lock
);
1211 hammer_rel_buffer(buffer
, 0);
1218 hammer_unref(&node
->lock
);
1219 hammer_flush_node(node
);
1221 hammer_rel_buffer(buffer
, 0);
1225 * Free space on-media associated with a B-Tree node.
1228 hammer_delete_node(hammer_transaction_t trans
, hammer_node_t node
)
1230 KKASSERT((node
->flags
& HAMMER_NODE_DELETED
) == 0);
1231 node
->flags
|= HAMMER_NODE_DELETED
;
1232 hammer_blockmap_free(trans
, node
->node_offset
, sizeof(*node
->ondisk
));
1236 * Passively cache a referenced hammer_node. The caller may release
1237 * the node on return.
1240 hammer_cache_node(hammer_node_cache_t cache
, hammer_node_t node
)
1243 * If the node doesn't exist, or is being deleted, don't cache it!
1245 * The node can only ever be NULL in the I/O failure path.
1247 if (node
== NULL
|| (node
->flags
& HAMMER_NODE_DELETED
))
1249 if (cache
->node
== node
)
1252 hammer_uncache_node(cache
);
1253 if (node
->flags
& HAMMER_NODE_DELETED
)
1256 TAILQ_INSERT_TAIL(&node
->cache_list
, cache
, entry
);
1260 hammer_uncache_node(hammer_node_cache_t cache
)
1264 if ((node
= cache
->node
) != NULL
) {
1265 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1267 if (TAILQ_EMPTY(&node
->cache_list
))
1268 hammer_flush_node(node
);
1273 * Remove a node's cache references and destroy the node if it has no
1274 * other references or backing store.
1277 hammer_flush_node(hammer_node_t node
)
1279 hammer_node_cache_t cache
;
1280 hammer_buffer_t buffer
;
1282 while ((cache
= TAILQ_FIRST(&node
->cache_list
)) != NULL
) {
1283 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1286 if (node
->lock
.refs
== 0 && node
->ondisk
== NULL
) {
1287 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1288 RB_REMOVE(hammer_nod_rb_tree
, &node
->hmp
->rb_nods_root
, node
);
1289 if ((buffer
= node
->buffer
) != NULL
) {
1290 node
->buffer
= NULL
;
1291 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1292 /* buffer is unreferenced because ondisk is NULL */
1294 --hammer_count_nodes
;
1295 kfree(node
, M_HAMMER
);
1300 * Flush passively cached B-Tree nodes associated with this buffer.
1301 * This is only called when the buffer is about to be destroyed, so
1302 * none of the nodes should have any references. The buffer is locked.
1304 * We may be interlocked with the buffer.
1307 hammer_flush_buffer_nodes(hammer_buffer_t buffer
)
1311 while ((node
= TAILQ_FIRST(&buffer
->clist
)) != NULL
) {
1312 KKASSERT(node
->ondisk
== NULL
);
1313 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1315 if (node
->lock
.refs
== 0) {
1316 hammer_ref(&node
->lock
);
1317 node
->flags
|= HAMMER_NODE_FLUSH
;
1318 hammer_rel_node(node
);
1320 KKASSERT(node
->loading
!= 0);
1321 KKASSERT(node
->buffer
!= NULL
);
1322 buffer
= node
->buffer
;
1323 node
->buffer
= NULL
;
1324 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1325 /* buffer is unreferenced because ondisk is NULL */
1331 /************************************************************************
1333 ************************************************************************/
1336 * Allocate a B-Tree node.
1339 hammer_alloc_btree(hammer_transaction_t trans
, int *errorp
)
1341 hammer_buffer_t buffer
= NULL
;
1342 hammer_node_t node
= NULL
;
1343 hammer_off_t node_offset
;
1345 node_offset
= hammer_blockmap_alloc(trans
, HAMMER_ZONE_BTREE_INDEX
,
1346 sizeof(struct hammer_node_ondisk
),
1349 node
= hammer_get_node(trans
->hmp
, node_offset
, 1, errorp
);
1350 hammer_modify_node_noundo(trans
, node
);
1351 bzero(node
->ondisk
, sizeof(*node
->ondisk
));
1352 hammer_modify_node_done(node
);
1355 hammer_rel_buffer(buffer
, 0);
1360 * Allocate data. If the address of a data buffer is supplied then
1361 * any prior non-NULL *data_bufferp will be released and *data_bufferp
1362 * will be set to the related buffer. The caller must release it when
1363 * finally done. The initial *data_bufferp should be set to NULL by
1366 * The caller is responsible for making hammer_modify*() calls on the
1370 hammer_alloc_data(hammer_transaction_t trans
, int32_t data_len
,
1371 u_int16_t rec_type
, hammer_off_t
*data_offsetp
,
1372 struct hammer_buffer
**data_bufferp
, int *errorp
)
1382 case HAMMER_RECTYPE_INODE
:
1383 case HAMMER_RECTYPE_DIRENTRY
:
1384 case HAMMER_RECTYPE_EXT
:
1385 case HAMMER_RECTYPE_FIX
:
1386 case HAMMER_RECTYPE_PFS
:
1387 zone
= HAMMER_ZONE_META_INDEX
;
1389 case HAMMER_RECTYPE_DATA
:
1390 case HAMMER_RECTYPE_DB
:
1391 if (data_len
<= HAMMER_BUFSIZE
/ 2) {
1392 zone
= HAMMER_ZONE_SMALL_DATA_INDEX
;
1394 data_len
= (data_len
+ HAMMER_BUFMASK
) &
1396 zone
= HAMMER_ZONE_LARGE_DATA_INDEX
;
1400 panic("hammer_alloc_data: rec_type %04x unknown",
1402 zone
= 0; /* NOT REACHED */
1405 *data_offsetp
= hammer_blockmap_alloc(trans
, zone
,
1410 if (*errorp
== 0 && data_bufferp
) {
1412 data
= hammer_bread_ext(trans
->hmp
, *data_offsetp
,
1413 data_len
, errorp
, data_bufferp
);
1424 * Sync dirty buffers to the media and clean-up any loose ends.
1426 * These functions do not start the flusher going, they simply
1427 * queue everything up to the flusher.
1429 static int hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
);
1430 static int hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
);
1433 hammer_queue_inodes_flusher(hammer_mount_t hmp
, int waitfor
)
1435 struct hammer_sync_info info
;
1438 info
.waitfor
= waitfor
;
1439 if (waitfor
== MNT_WAIT
) {
1440 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
,
1441 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1443 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
|VMSC_NOWAIT
,
1444 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1450 * Filesystem sync. If doing a synchronous sync make a second pass on
1451 * the vnodes in case any were already flushing during the first pass,
1452 * and activate the flusher twice (the second time brings the UNDO FIFO's
1453 * start position up to the end position after the first call).
1456 hammer_sync_hmp(hammer_mount_t hmp
, int waitfor
)
1458 struct hammer_sync_info info
;
1461 info
.waitfor
= MNT_NOWAIT
;
1462 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_NOWAIT
,
1463 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1464 if (info
.error
== 0 && waitfor
== MNT_WAIT
) {
1465 info
.waitfor
= waitfor
;
1466 vmntvnodescan(hmp
->mp
, VMSC_GETVP
,
1467 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1469 if (waitfor
== MNT_WAIT
) {
1470 hammer_flusher_sync(hmp
);
1471 hammer_flusher_sync(hmp
);
1473 hammer_flusher_async(hmp
, NULL
);
1479 hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
)
1481 struct hammer_inode
*ip
;
1484 if (vp
->v_type
== VNON
|| ip
== NULL
||
1485 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1486 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1493 hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
)
1495 struct hammer_sync_info
*info
= data
;
1496 struct hammer_inode
*ip
;
1500 if (vp
->v_type
== VNON
|| vp
->v_type
== VBAD
||
1501 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1502 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1505 error
= VOP_FSYNC(vp
, MNT_NOWAIT
);
1507 info
->error
= error
;