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_transaction_t trans
,
52 hammer_node_t node
, int isnew
);
55 hammer_vol_rb_compare(hammer_volume_t vol1
, hammer_volume_t vol2
)
57 if (vol1
->vol_no
< vol2
->vol_no
)
59 if (vol1
->vol_no
> vol2
->vol_no
)
65 * hammer_buffer structures are indexed via their zoneX_offset, not
69 hammer_buf_rb_compare(hammer_buffer_t buf1
, hammer_buffer_t buf2
)
71 if (buf1
->zoneX_offset
< buf2
->zoneX_offset
)
73 if (buf1
->zoneX_offset
> buf2
->zoneX_offset
)
79 hammer_nod_rb_compare(hammer_node_t node1
, hammer_node_t node2
)
81 if (node1
->node_offset
< node2
->node_offset
)
83 if (node1
->node_offset
> node2
->node_offset
)
88 RB_GENERATE2(hammer_vol_rb_tree
, hammer_volume
, rb_node
,
89 hammer_vol_rb_compare
, int32_t, vol_no
);
90 RB_GENERATE2(hammer_buf_rb_tree
, hammer_buffer
, rb_node
,
91 hammer_buf_rb_compare
, hammer_off_t
, zoneX_offset
);
92 RB_GENERATE2(hammer_nod_rb_tree
, hammer_node
, rb_node
,
93 hammer_nod_rb_compare
, hammer_off_t
, node_offset
);
95 /************************************************************************
97 ************************************************************************
99 * Load a HAMMER volume by name. Returns 0 on success or a positive error
100 * code on failure. Volumes must be loaded at mount time, get_volume() will
101 * not load a new volume.
103 * Calls made to hammer_load_volume() or single-threaded
106 hammer_install_volume(struct hammer_mount
*hmp
, const char *volname
,
110 hammer_volume_t volume
;
111 struct hammer_volume_ondisk
*ondisk
;
112 struct nlookupdata nd
;
113 struct buf
*bp
= NULL
;
119 ronly
= ((mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
122 * Allocate a volume structure
124 ++hammer_count_volumes
;
125 volume
= kmalloc(sizeof(*volume
), hmp
->m_misc
, M_WAITOK
|M_ZERO
);
126 volume
->vol_name
= kstrdup(volname
, hmp
->m_misc
);
127 volume
->io
.hmp
= hmp
; /* bootstrap */
128 hammer_io_init(&volume
->io
, volume
, HAMMER_STRUCTURE_VOLUME
);
129 volume
->io
.offset
= 0LL;
130 volume
->io
.bytes
= HAMMER_BUFSIZE
;
133 * Get the device vnode
136 error
= nlookup_init(&nd
, volume
->vol_name
, UIO_SYSSPACE
, NLC_FOLLOW
);
138 error
= nlookup(&nd
);
140 error
= cache_vref(&nd
.nl_nch
, nd
.nl_cred
, &volume
->devvp
);
144 volume
->devvp
= devvp
;
148 if (vn_isdisk(volume
->devvp
, &error
)) {
149 error
= vfs_mountedon(volume
->devvp
);
153 count_udev(volume
->devvp
->v_umajor
, volume
->devvp
->v_uminor
) > 0) {
157 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
158 error
= vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
160 error
= VOP_OPEN(volume
->devvp
,
161 (ronly
? FREAD
: FREAD
|FWRITE
),
164 vn_unlock(volume
->devvp
);
167 hammer_free_volume(volume
);
170 volume
->devvp
->v_rdev
->si_mountpoint
= mp
;
174 * Extract the volume number from the volume header and do various
177 error
= bread(volume
->devvp
, 0LL, HAMMER_BUFSIZE
, &bp
);
180 ondisk
= (void *)bp
->b_data
;
181 if (ondisk
->vol_signature
!= HAMMER_FSBUF_VOLUME
) {
182 kprintf("hammer_mount: volume %s has an invalid header\n",
187 volume
->vol_no
= ondisk
->vol_no
;
188 volume
->buffer_base
= ondisk
->vol_buf_beg
;
189 volume
->vol_flags
= ondisk
->vol_flags
;
190 volume
->nblocks
= ondisk
->vol_nblocks
;
191 volume
->maxbuf_off
= HAMMER_ENCODE_RAW_BUFFER(volume
->vol_no
,
192 ondisk
->vol_buf_end
- ondisk
->vol_buf_beg
);
193 volume
->maxraw_off
= ondisk
->vol_buf_end
;
195 if (RB_EMPTY(&hmp
->rb_vols_root
)) {
196 hmp
->fsid
= ondisk
->vol_fsid
;
197 } else if (bcmp(&hmp
->fsid
, &ondisk
->vol_fsid
, sizeof(uuid_t
))) {
198 kprintf("hammer_mount: volume %s's fsid does not match "
199 "other volumes\n", volume
->vol_name
);
205 * Insert the volume structure into the red-black tree.
207 if (RB_INSERT(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
)) {
208 kprintf("hammer_mount: volume %s has a duplicate vol_no %d\n",
209 volume
->vol_name
, volume
->vol_no
);
214 * Set the root volume . HAMMER special cases rootvol the structure.
215 * We do not hold a ref because this would prevent related I/O
216 * from being flushed.
218 if (error
== 0 && ondisk
->vol_rootvol
== ondisk
->vol_no
) {
219 hmp
->rootvol
= volume
;
220 hmp
->nvolumes
= ondisk
->vol_count
;
225 hmp
->mp
->mnt_stat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
226 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
227 hmp
->mp
->mnt_vstat
.f_blocks
+= ondisk
->vol0_stat_bigblocks
*
228 (HAMMER_LARGEBLOCK_SIZE
/ HAMMER_BUFSIZE
);
234 /*vinvalbuf(volume->devvp, V_SAVE, 0, 0);*/
236 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
237 VOP_CLOSE(volume
->devvp
, ronly
? FREAD
: FREAD
|FWRITE
);
238 hammer_free_volume(volume
);
244 * This is called for each volume when updating the mount point from
245 * read-write to read-only or vise-versa.
248 hammer_adjust_volume_mode(hammer_volume_t volume
, void *data __unused
)
251 vn_lock(volume
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
252 if (volume
->io
.hmp
->ronly
) {
253 /* do not call vinvalbuf */
254 VOP_OPEN(volume
->devvp
, FREAD
, FSCRED
, NULL
);
255 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
257 /* do not call vinvalbuf */
258 VOP_OPEN(volume
->devvp
, FREAD
|FWRITE
, FSCRED
, NULL
);
259 VOP_CLOSE(volume
->devvp
, FREAD
);
261 vn_unlock(volume
->devvp
);
267 * Unload and free a HAMMER volume. Must return >= 0 to continue scan
268 * so returns -1 on failure.
271 hammer_unload_volume(hammer_volume_t volume
, void *data __unused
)
273 hammer_mount_t hmp
= volume
->io
.hmp
;
274 int ronly
= ((hmp
->mp
->mnt_flag
& MNT_RDONLY
) ? 1 : 0);
278 * Clean up the root volume pointer, which is held unlocked in hmp.
280 if (hmp
->rootvol
== volume
)
284 * We must not flush a dirty buffer to disk on umount. It should
285 * have already been dealt with by the flusher, or we may be in
286 * catastrophic failure.
288 hammer_io_clear_modify(&volume
->io
, 1);
289 volume
->io
.waitdep
= 1;
290 bp
= hammer_io_release(&volume
->io
, 1);
293 * Clean up the persistent ref ioerror might have on the volume
295 if (volume
->io
.ioerror
) {
296 volume
->io
.ioerror
= 0;
297 hammer_unref(&volume
->io
.lock
);
301 * There should be no references on the volume, no clusters, and
304 KKASSERT(volume
->io
.lock
.refs
== 0);
308 volume
->ondisk
= NULL
;
310 if (volume
->devvp
->v_rdev
&&
311 volume
->devvp
->v_rdev
->si_mountpoint
== hmp
->mp
313 volume
->devvp
->v_rdev
->si_mountpoint
= NULL
;
317 * Make sure we don't sync anything to disk if we
318 * are in read-only mode (1) or critically-errored
319 * (2). Note that there may be dirty buffers in
320 * normal read-only mode from crash recovery.
322 vinvalbuf(volume
->devvp
, 0, 0, 0);
323 VOP_CLOSE(volume
->devvp
, FREAD
);
326 * Normal termination, save any dirty buffers
327 * (XXX there really shouldn't be any).
329 vinvalbuf(volume
->devvp
, V_SAVE
, 0, 0);
330 VOP_CLOSE(volume
->devvp
, FREAD
|FWRITE
);
335 * Destroy the structure
337 RB_REMOVE(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, volume
);
338 hammer_free_volume(volume
);
344 hammer_free_volume(hammer_volume_t volume
)
346 hammer_mount_t hmp
= volume
->io
.hmp
;
348 if (volume
->vol_name
) {
349 kfree(volume
->vol_name
, hmp
->m_misc
);
350 volume
->vol_name
= NULL
;
353 vrele(volume
->devvp
);
354 volume
->devvp
= NULL
;
356 --hammer_count_volumes
;
357 kfree(volume
, hmp
->m_misc
);
361 * Get a HAMMER volume. The volume must already exist.
364 hammer_get_volume(struct hammer_mount
*hmp
, int32_t vol_no
, int *errorp
)
366 struct hammer_volume
*volume
;
369 * Locate the volume structure
371 volume
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, vol_no
);
372 if (volume
== NULL
) {
376 hammer_ref(&volume
->io
.lock
);
379 * Deal with on-disk info
381 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
382 *errorp
= hammer_load_volume(volume
);
384 hammer_rel_volume(volume
, 1);
394 hammer_ref_volume(hammer_volume_t volume
)
398 hammer_ref(&volume
->io
.lock
);
401 * Deal with on-disk info
403 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
404 error
= hammer_load_volume(volume
);
406 hammer_rel_volume(volume
, 1);
414 hammer_get_root_volume(struct hammer_mount
*hmp
, int *errorp
)
416 hammer_volume_t volume
;
418 volume
= hmp
->rootvol
;
419 KKASSERT(volume
!= NULL
);
420 hammer_ref(&volume
->io
.lock
);
423 * Deal with on-disk info
425 if (volume
->ondisk
== NULL
|| volume
->io
.loading
) {
426 *errorp
= hammer_load_volume(volume
);
428 hammer_rel_volume(volume
, 1);
438 * Load a volume's on-disk information. The volume must be referenced and
439 * not locked. We temporarily acquire an exclusive lock to interlock
440 * against releases or multiple get's.
443 hammer_load_volume(hammer_volume_t volume
)
447 ++volume
->io
.loading
;
448 hammer_lock_ex(&volume
->io
.lock
);
450 if (volume
->ondisk
== NULL
) {
451 error
= hammer_io_read(volume
->devvp
, &volume
->io
,
454 volume
->ondisk
= (void *)volume
->io
.bp
->b_data
;
458 --volume
->io
.loading
;
459 hammer_unlock(&volume
->io
.lock
);
464 * Release a volume. Call hammer_io_release on the last reference. We have
465 * to acquire an exclusive lock to interlock against volume->ondisk tests
466 * in hammer_load_volume(), and hammer_io_release() also expects an exclusive
469 * Volumes are not unloaded from memory during normal operation.
472 hammer_rel_volume(hammer_volume_t volume
, int flush
)
474 struct buf
*bp
= NULL
;
477 if (volume
->io
.lock
.refs
== 1) {
478 ++volume
->io
.loading
;
479 hammer_lock_ex(&volume
->io
.lock
);
480 if (volume
->io
.lock
.refs
== 1) {
481 volume
->ondisk
= NULL
;
482 bp
= hammer_io_release(&volume
->io
, flush
);
484 --volume
->io
.loading
;
485 hammer_unlock(&volume
->io
.lock
);
487 hammer_unref(&volume
->io
.lock
);
494 hammer_mountcheck_volumes(struct hammer_mount
*hmp
)
499 for (i
= 0; i
< hmp
->nvolumes
; ++i
) {
500 vol
= RB_LOOKUP(hammer_vol_rb_tree
, &hmp
->rb_vols_root
, i
);
507 /************************************************************************
509 ************************************************************************
511 * Manage buffers. Currently all blockmap-backed zones are direct-mapped
512 * to zone-2 buffer offsets, without a translation stage. However, the
513 * hammer_buffer structure is indexed by its zoneX_offset, not its
516 * The proper zone must be maintained throughout the code-base all the way
517 * through to the big-block allocator, or routines like hammer_del_buffers()
518 * will not be able to locate all potentially conflicting buffers.
521 hammer_get_buffer(hammer_mount_t hmp
, hammer_off_t buf_offset
,
522 int bytes
, int isnew
, int *errorp
)
524 hammer_buffer_t buffer
;
525 hammer_volume_t volume
;
526 hammer_off_t zone2_offset
;
527 hammer_io_type_t iotype
;
531 buf_offset
&= ~HAMMER_BUFMASK64
;
534 * Shortcut if the buffer is already cached
536 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buf_offset
);
538 if (buffer
->io
.lock
.refs
== 0)
539 ++hammer_count_refedbufs
;
540 hammer_ref(&buffer
->io
.lock
);
543 * Once refed the ondisk field will not be cleared by
546 if (buffer
->ondisk
&& buffer
->io
.loading
== 0) {
552 * The buffer is no longer loose if it has a ref, and
553 * cannot become loose once it gains a ref. Loose
554 * buffers will never be in a modified state. This should
555 * only occur on the 0->1 transition of refs.
557 * lose_list can be modified via a biodone() interrupt.
559 if (buffer
->io
.mod_list
== &hmp
->lose_list
) {
560 crit_enter(); /* biodone race against list */
561 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
,
564 buffer
->io
.mod_list
= NULL
;
565 KKASSERT(buffer
->io
.modified
== 0);
571 * What is the buffer class?
573 zone
= HAMMER_ZONE_DECODE(buf_offset
);
576 case HAMMER_ZONE_LARGE_DATA_INDEX
:
577 case HAMMER_ZONE_SMALL_DATA_INDEX
:
578 iotype
= HAMMER_STRUCTURE_DATA_BUFFER
;
580 case HAMMER_ZONE_UNDO_INDEX
:
581 iotype
= HAMMER_STRUCTURE_UNDO_BUFFER
;
583 case HAMMER_ZONE_META_INDEX
:
586 * NOTE: inode data and directory entries are placed in this
587 * zone. inode atime/mtime is updated in-place and thus
588 * buffers containing inodes must be synchronized as
589 * meta-buffers, same as buffers containing B-Tree info.
591 iotype
= HAMMER_STRUCTURE_META_BUFFER
;
596 * Handle blockmap offset translations
598 if (zone
>= HAMMER_ZONE_BTREE_INDEX
) {
599 zone2_offset
= hammer_blockmap_lookup(hmp
, buf_offset
, errorp
);
600 } else if (zone
== HAMMER_ZONE_UNDO_INDEX
) {
601 zone2_offset
= hammer_undo_lookup(hmp
, buf_offset
, errorp
);
603 KKASSERT(zone
== HAMMER_ZONE_RAW_BUFFER_INDEX
);
604 zone2_offset
= buf_offset
;
611 * NOTE: zone2_offset and maxbuf_off are both full zone-2 offset
614 KKASSERT((zone2_offset
& HAMMER_OFF_ZONE_MASK
) ==
615 HAMMER_ZONE_RAW_BUFFER
);
616 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
617 volume
= hammer_get_volume(hmp
, vol_no
, errorp
);
621 KKASSERT(zone2_offset
< volume
->maxbuf_off
);
624 * Allocate a new buffer structure. We will check for races later.
626 ++hammer_count_buffers
;
627 buffer
= kmalloc(sizeof(*buffer
), hmp
->m_misc
,
628 M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
629 buffer
->zone2_offset
= zone2_offset
;
630 buffer
->zoneX_offset
= buf_offset
;
632 hammer_io_init(&buffer
->io
, volume
, iotype
);
633 buffer
->io
.offset
= volume
->ondisk
->vol_buf_beg
+
634 (zone2_offset
& HAMMER_OFF_SHORT_MASK
);
635 buffer
->io
.bytes
= bytes
;
636 TAILQ_INIT(&buffer
->clist
);
637 hammer_ref(&buffer
->io
.lock
);
640 * Insert the buffer into the RB tree and handle late collisions.
642 if (RB_INSERT(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
, buffer
)) {
643 hammer_unref(&buffer
->io
.lock
); /* safety */
644 --hammer_count_buffers
;
645 hammer_rel_volume(volume
, 0);
646 buffer
->io
.volume
= NULL
; /* safety */
647 kfree(buffer
, hmp
->m_misc
);
650 ++hammer_count_refedbufs
;
654 * Deal with on-disk info and loading races.
656 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
657 *errorp
= hammer_load_buffer(buffer
, isnew
);
659 hammer_rel_buffer(buffer
, 1);
669 * This is used by the direct-read code to deal with large-data buffers
670 * created by the reblocker and mirror-write code. The direct-read code
671 * bypasses the HAMMER buffer subsystem and so any aliased dirty or write-
672 * running hammer buffers must be fully synced to disk before we can issue
675 * This code path is not considered critical as only the rebocker and
676 * mirror-write code will create large-data buffers via the HAMMER buffer
677 * subsystem. They do that because they operate at the B-Tree level and
678 * do not access the vnode/inode structures.
681 hammer_sync_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
, int bytes
)
683 hammer_buffer_t buffer
;
686 KKASSERT((base_offset
& HAMMER_OFF_ZONE_MASK
) ==
687 HAMMER_ZONE_LARGE_DATA
);
690 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
692 if (buffer
&& (buffer
->io
.modified
|| buffer
->io
.running
)) {
693 error
= hammer_ref_buffer(buffer
);
695 hammer_io_wait(&buffer
->io
);
696 if (buffer
->io
.modified
) {
697 hammer_io_write_interlock(&buffer
->io
);
698 hammer_io_flush(&buffer
->io
);
699 hammer_io_done_interlock(&buffer
->io
);
700 hammer_io_wait(&buffer
->io
);
702 hammer_rel_buffer(buffer
, 0);
705 base_offset
+= HAMMER_BUFSIZE
;
706 bytes
-= HAMMER_BUFSIZE
;
711 * Destroy all buffers covering the specified zoneX offset range. This
712 * is called when the related blockmap layer2 entry is freed or when
713 * a direct write bypasses our buffer/buffer-cache subsystem.
715 * The buffers may be referenced by the caller itself. Setting reclaim
716 * will cause the buffer to be destroyed when it's ref count reaches zero.
718 * Return 0 on success, EAGAIN if some buffers could not be destroyed due
719 * to additional references held by other threads, or some other (typically
723 hammer_del_buffers(hammer_mount_t hmp
, hammer_off_t base_offset
,
724 hammer_off_t zone2_offset
, int bytes
,
725 int report_conflicts
)
727 hammer_buffer_t buffer
;
728 hammer_volume_t volume
;
733 vol_no
= HAMMER_VOL_DECODE(zone2_offset
);
734 volume
= hammer_get_volume(hmp
, vol_no
, &ret_error
);
735 KKASSERT(ret_error
== 0);
738 buffer
= RB_LOOKUP(hammer_buf_rb_tree
, &hmp
->rb_bufs_root
,
741 error
= hammer_ref_buffer(buffer
);
742 if (error
== 0 && buffer
->io
.lock
.refs
!= 1) {
744 hammer_rel_buffer(buffer
, 0);
747 KKASSERT(buffer
->zone2_offset
== zone2_offset
);
748 hammer_io_clear_modify(&buffer
->io
, 1);
749 buffer
->io
.reclaim
= 1;
750 buffer
->io
.waitdep
= 1;
751 KKASSERT(buffer
->io
.volume
== volume
);
752 hammer_rel_buffer(buffer
, 0);
755 error
= hammer_io_inval(volume
, zone2_offset
);
759 if (report_conflicts
||
760 (hammer_debug_general
& 0x8000)) {
761 kprintf("hammer_del_buffers: unable to "
762 "invalidate %016llx buffer=%p rep=%d\n",
763 (long long)base_offset
,
764 buffer
, report_conflicts
);
767 base_offset
+= HAMMER_BUFSIZE
;
768 zone2_offset
+= HAMMER_BUFSIZE
;
769 bytes
-= HAMMER_BUFSIZE
;
771 hammer_rel_volume(volume
, 0);
776 hammer_load_buffer(hammer_buffer_t buffer
, int isnew
)
778 hammer_volume_t volume
;
782 * Load the buffer's on-disk info
784 volume
= buffer
->io
.volume
;
785 ++buffer
->io
.loading
;
786 hammer_lock_ex(&buffer
->io
.lock
);
788 if (hammer_debug_io
& 0x0001) {
789 kprintf("load_buffer %016llx %016llx isnew=%d od=%p\n",
790 (long long)buffer
->zoneX_offset
,
791 (long long)buffer
->zone2_offset
,
792 isnew
, buffer
->ondisk
);
795 if (buffer
->ondisk
== NULL
) {
797 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
799 error
= hammer_io_read(volume
->devvp
, &buffer
->io
,
803 buffer
->ondisk
= (void *)buffer
->io
.bp
->b_data
;
805 error
= hammer_io_new(volume
->devvp
, &buffer
->io
);
809 --buffer
->io
.loading
;
810 hammer_unlock(&buffer
->io
.lock
);
815 * NOTE: Called from RB_SCAN, must return >= 0 for scan to continue.
816 * This routine is only called during unmount.
819 hammer_unload_buffer(hammer_buffer_t buffer
, void *data __unused
)
822 * Clean up the persistent ref ioerror might have on the buffer
823 * and acquire a ref (steal ioerror's if we can).
825 if (buffer
->io
.ioerror
) {
826 buffer
->io
.ioerror
= 0;
828 if (buffer
->io
.lock
.refs
== 0)
829 ++hammer_count_refedbufs
;
830 hammer_ref(&buffer
->io
.lock
);
834 * We must not flush a dirty buffer to disk on umount. It should
835 * have already been dealt with by the flusher, or we may be in
836 * catastrophic failure.
838 hammer_io_clear_modify(&buffer
->io
, 1);
839 hammer_flush_buffer_nodes(buffer
);
840 KKASSERT(buffer
->io
.lock
.refs
== 1);
841 hammer_rel_buffer(buffer
, 2);
846 * Reference a buffer that is either already referenced or via a specially
847 * handled pointer (aka cursor->buffer).
850 hammer_ref_buffer(hammer_buffer_t buffer
)
854 if (buffer
->io
.lock
.refs
== 0)
855 ++hammer_count_refedbufs
;
856 hammer_ref(&buffer
->io
.lock
);
859 * At this point a biodone() will not touch the buffer other then
860 * incidental bits. However, lose_list can be modified via
861 * a biodone() interrupt.
865 if (buffer
->io
.mod_list
== &buffer
->io
.hmp
->lose_list
) {
867 TAILQ_REMOVE(buffer
->io
.mod_list
, &buffer
->io
, mod_entry
);
868 buffer
->io
.mod_list
= NULL
;
872 if (buffer
->ondisk
== NULL
|| buffer
->io
.loading
) {
873 error
= hammer_load_buffer(buffer
, 0);
875 hammer_rel_buffer(buffer
, 1);
877 * NOTE: buffer pointer can become stale after
888 * Release a buffer. We have to deal with several places where
889 * another thread can ref the buffer.
891 * Only destroy the structure itself if the related buffer cache buffer
892 * was disassociated from it. This ties the management of the structure
893 * to the buffer cache subsystem. buffer->ondisk determines whether the
894 * embedded io is referenced or not.
897 hammer_rel_buffer(hammer_buffer_t buffer
, int flush
)
899 hammer_volume_t volume
;
901 struct buf
*bp
= NULL
;
904 hmp
= buffer
->io
.hmp
;
907 if (buffer
->io
.lock
.refs
== 1) {
908 ++buffer
->io
.loading
; /* force interlock check */
909 hammer_lock_ex(&buffer
->io
.lock
);
910 if (buffer
->io
.lock
.refs
== 1) {
911 bp
= hammer_io_release(&buffer
->io
, flush
);
913 if (buffer
->io
.lock
.refs
== 1)
914 --hammer_count_refedbufs
;
916 if (buffer
->io
.bp
== NULL
&&
917 buffer
->io
.lock
.refs
== 1) {
921 * NOTE: It is impossible for any associated
922 * B-Tree nodes to have refs if the buffer
923 * has no additional refs.
925 RB_REMOVE(hammer_buf_rb_tree
,
926 &buffer
->io
.hmp
->rb_bufs_root
,
928 volume
= buffer
->io
.volume
;
929 buffer
->io
.volume
= NULL
; /* sanity */
930 hammer_rel_volume(volume
, 0);
931 hammer_io_clear_modlist(&buffer
->io
);
932 hammer_flush_buffer_nodes(buffer
);
933 KKASSERT(TAILQ_EMPTY(&buffer
->clist
));
937 --buffer
->io
.loading
;
938 hammer_unlock(&buffer
->io
.lock
);
940 hammer_unref(&buffer
->io
.lock
);
945 --hammer_count_buffers
;
946 kfree(buffer
, hmp
->m_misc
);
951 * Access the filesystem buffer containing the specified hammer offset.
952 * buf_offset is a conglomeration of the volume number and vol_buf_beg
953 * relative buffer offset. It must also have bit 55 set to be valid.
954 * (see hammer_off_t in hammer_disk.h).
956 * Any prior buffer in *bufferp will be released and replaced by the
959 * NOTE: The buffer is indexed via its zoneX_offset but we allow the
960 * passed cached *bufferp to match against either zoneX or zone2.
964 _hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
965 int *errorp
, struct hammer_buffer
**bufferp
)
967 hammer_buffer_t buffer
;
968 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
970 buf_offset
&= ~HAMMER_BUFMASK64
;
971 KKASSERT((buf_offset
& HAMMER_OFF_ZONE_MASK
) != 0);
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
, 0, errorp
);
985 * Return a pointer to the buffer data.
990 return((char *)buffer
->ondisk
+ xoff
);
994 hammer_bread(hammer_mount_t hmp
, hammer_off_t buf_offset
,
995 int *errorp
, struct hammer_buffer
**bufferp
)
997 return(_hammer_bread(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
1001 hammer_bread_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_bread(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
1009 * Access the filesystem buffer containing the specified hammer offset.
1010 * No disk read operation occurs. The result buffer may contain garbage.
1012 * Any prior buffer in *bufferp will be released and replaced by the
1015 * This function marks the buffer dirty but does not increment its
1016 * modify_refs count.
1020 _hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
1021 int *errorp
, struct hammer_buffer
**bufferp
)
1023 hammer_buffer_t buffer
;
1024 int32_t xoff
= (int32_t)buf_offset
& HAMMER_BUFMASK
;
1026 buf_offset
&= ~HAMMER_BUFMASK64
;
1029 if (buffer
== NULL
|| (buffer
->zone2_offset
!= buf_offset
&&
1030 buffer
->zoneX_offset
!= buf_offset
)) {
1032 hammer_rel_buffer(buffer
, 0);
1033 buffer
= hammer_get_buffer(hmp
, buf_offset
, bytes
, 1, errorp
);
1040 * Return a pointer to the buffer data.
1045 return((char *)buffer
->ondisk
+ xoff
);
1049 hammer_bnew(hammer_mount_t hmp
, hammer_off_t buf_offset
,
1050 int *errorp
, struct hammer_buffer
**bufferp
)
1052 return(_hammer_bnew(hmp
, buf_offset
, HAMMER_BUFSIZE
, errorp
, bufferp
));
1056 hammer_bnew_ext(hammer_mount_t hmp
, hammer_off_t buf_offset
, int bytes
,
1057 int *errorp
, struct hammer_buffer
**bufferp
)
1059 bytes
= (bytes
+ HAMMER_BUFMASK
) & ~HAMMER_BUFMASK
;
1060 return(_hammer_bnew(hmp
, buf_offset
, bytes
, errorp
, bufferp
));
1063 /************************************************************************
1065 ************************************************************************
1067 * Manage B-Tree nodes. B-Tree nodes represent the primary indexing
1068 * method used by the HAMMER filesystem.
1070 * Unlike other HAMMER structures, a hammer_node can be PASSIVELY
1071 * associated with its buffer, and will only referenced the buffer while
1072 * the node itself is referenced.
1074 * A hammer_node can also be passively associated with other HAMMER
1075 * structures, such as inodes, while retaining 0 references. These
1076 * associations can be cleared backwards using a pointer-to-pointer in
1079 * This allows the HAMMER implementation to cache hammer_nodes long-term
1080 * and short-cut a great deal of the infrastructure's complexity. In
1081 * most cases a cached node can be reacquired without having to dip into
1082 * either the buffer or cluster management code.
1084 * The caller must pass a referenced cluster on call and will retain
1085 * ownership of the reference on return. The node will acquire its own
1086 * additional references, if necessary.
1089 hammer_get_node(hammer_transaction_t trans
, hammer_off_t node_offset
,
1090 int isnew
, int *errorp
)
1092 hammer_mount_t hmp
= trans
->hmp
;
1095 KKASSERT((node_offset
& HAMMER_OFF_ZONE_MASK
) == HAMMER_ZONE_BTREE
);
1098 * Locate the structure, allocating one if necessary.
1101 node
= RB_LOOKUP(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node_offset
);
1103 ++hammer_count_nodes
;
1104 node
= kmalloc(sizeof(*node
), hmp
->m_misc
, M_WAITOK
|M_ZERO
|M_USE_RESERVE
);
1105 node
->node_offset
= node_offset
;
1107 TAILQ_INIT(&node
->cursor_list
);
1108 TAILQ_INIT(&node
->cache_list
);
1109 if (RB_INSERT(hammer_nod_rb_tree
, &hmp
->rb_nods_root
, node
)) {
1110 --hammer_count_nodes
;
1111 kfree(node
, hmp
->m_misc
);
1115 hammer_ref(&node
->lock
);
1119 *errorp
= hammer_load_node(trans
, node
, isnew
);
1120 trans
->flags
|= HAMMER_TRANSF_DIDIO
;
1123 hammer_rel_node(node
);
1130 * Reference an already-referenced node.
1133 hammer_ref_node(hammer_node_t node
)
1135 KKASSERT(node
->lock
.refs
> 0 && node
->ondisk
!= NULL
);
1136 hammer_ref(&node
->lock
);
1140 * Load a node's on-disk data reference.
1143 hammer_load_node(hammer_transaction_t trans
, hammer_node_t node
, int isnew
)
1145 hammer_buffer_t buffer
;
1146 hammer_off_t buf_offset
;
1151 hammer_lock_ex(&node
->lock
);
1152 if (node
->ondisk
== NULL
) {
1154 * This is a little confusing but the jist is that
1155 * node->buffer determines whether the node is on
1156 * the buffer's clist and node->ondisk determines
1157 * whether the buffer is referenced.
1159 * We could be racing a buffer release, in which case
1160 * node->buffer may become NULL while we are blocked
1161 * referencing the buffer.
1163 if ((buffer
= node
->buffer
) != NULL
) {
1164 error
= hammer_ref_buffer(buffer
);
1165 if (error
== 0 && node
->buffer
== NULL
) {
1166 TAILQ_INSERT_TAIL(&buffer
->clist
,
1168 node
->buffer
= buffer
;
1171 buf_offset
= node
->node_offset
& ~HAMMER_BUFMASK64
;
1172 buffer
= hammer_get_buffer(node
->hmp
, buf_offset
,
1173 HAMMER_BUFSIZE
, 0, &error
);
1175 KKASSERT(error
== 0);
1176 TAILQ_INSERT_TAIL(&buffer
->clist
,
1178 node
->buffer
= buffer
;
1183 node
->ondisk
= (void *)((char *)buffer
->ondisk
+
1184 (node
->node_offset
& HAMMER_BUFMASK
));
1187 * Check CRC. NOTE: Neither flag is set and the CRC is not
1188 * generated on new B-Tree nodes.
1191 (node
->flags
& HAMMER_NODE_CRCANY
) == 0) {
1192 if (hammer_crc_test_btree(node
->ondisk
) == 0) {
1193 if (hammer_debug_debug
& 0x0002)
1194 Debugger("CRC FAILED: B-TREE NODE");
1195 node
->flags
|= HAMMER_NODE_CRCBAD
;
1197 node
->flags
|= HAMMER_NODE_CRCGOOD
;
1201 if (node
->flags
& HAMMER_NODE_CRCBAD
) {
1202 if (trans
->flags
& HAMMER_TRANSF_CRCDOM
)
1209 hammer_unlock(&node
->lock
);
1214 * Safely reference a node, interlock against flushes via the IO subsystem.
1217 hammer_ref_node_safe(hammer_transaction_t trans
, hammer_node_cache_t cache
,
1224 hammer_ref(&node
->lock
);
1226 if (node
->flags
& HAMMER_NODE_CRCBAD
) {
1227 if (trans
->flags
& HAMMER_TRANSF_CRCDOM
)
1235 *errorp
= hammer_load_node(trans
, node
, 0);
1238 hammer_rel_node(node
);
1248 * Release a hammer_node. On the last release the node dereferences
1249 * its underlying buffer and may or may not be destroyed.
1252 hammer_rel_node(hammer_node_t node
)
1254 hammer_buffer_t buffer
;
1257 * If this isn't the last ref just decrement the ref count and
1260 if (node
->lock
.refs
> 1) {
1261 hammer_unref(&node
->lock
);
1266 * If there is no ondisk info or no buffer the node failed to load,
1267 * remove the last reference and destroy the node.
1269 if (node
->ondisk
== NULL
) {
1270 hammer_unref(&node
->lock
);
1271 hammer_flush_node(node
);
1272 /* node is stale now */
1277 * Do not disassociate the node from the buffer if it represents
1278 * a modified B-Tree node that still needs its crc to be generated.
1280 if (node
->flags
& HAMMER_NODE_NEEDSCRC
)
1284 * Do final cleanups and then either destroy the node and leave it
1285 * passively cached. The buffer reference is removed regardless.
1287 buffer
= node
->buffer
;
1288 node
->ondisk
= NULL
;
1290 if ((node
->flags
& HAMMER_NODE_FLUSH
) == 0) {
1291 hammer_unref(&node
->lock
);
1292 hammer_rel_buffer(buffer
, 0);
1299 hammer_unref(&node
->lock
);
1300 hammer_flush_node(node
);
1302 hammer_rel_buffer(buffer
, 0);
1306 * Free space on-media associated with a B-Tree node.
1309 hammer_delete_node(hammer_transaction_t trans
, hammer_node_t node
)
1311 KKASSERT((node
->flags
& HAMMER_NODE_DELETED
) == 0);
1312 node
->flags
|= HAMMER_NODE_DELETED
;
1313 hammer_blockmap_free(trans
, node
->node_offset
, sizeof(*node
->ondisk
));
1317 * Passively cache a referenced hammer_node. The caller may release
1318 * the node on return.
1321 hammer_cache_node(hammer_node_cache_t cache
, hammer_node_t node
)
1324 * If the node doesn't exist, or is being deleted, don't cache it!
1326 * The node can only ever be NULL in the I/O failure path.
1328 if (node
== NULL
|| (node
->flags
& HAMMER_NODE_DELETED
))
1330 if (cache
->node
== node
)
1333 hammer_uncache_node(cache
);
1334 if (node
->flags
& HAMMER_NODE_DELETED
)
1337 TAILQ_INSERT_TAIL(&node
->cache_list
, cache
, entry
);
1341 hammer_uncache_node(hammer_node_cache_t cache
)
1345 if ((node
= cache
->node
) != NULL
) {
1346 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1348 if (TAILQ_EMPTY(&node
->cache_list
))
1349 hammer_flush_node(node
);
1354 * Remove a node's cache references and destroy the node if it has no
1355 * other references or backing store.
1358 hammer_flush_node(hammer_node_t node
)
1360 hammer_node_cache_t cache
;
1361 hammer_buffer_t buffer
;
1362 hammer_mount_t hmp
= node
->hmp
;
1364 while ((cache
= TAILQ_FIRST(&node
->cache_list
)) != NULL
) {
1365 TAILQ_REMOVE(&node
->cache_list
, cache
, entry
);
1368 if (node
->lock
.refs
== 0 && node
->ondisk
== NULL
) {
1369 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1370 RB_REMOVE(hammer_nod_rb_tree
, &node
->hmp
->rb_nods_root
, node
);
1371 if ((buffer
= node
->buffer
) != NULL
) {
1372 node
->buffer
= NULL
;
1373 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1374 /* buffer is unreferenced because ondisk is NULL */
1376 --hammer_count_nodes
;
1377 kfree(node
, hmp
->m_misc
);
1382 * Flush passively cached B-Tree nodes associated with this buffer.
1383 * This is only called when the buffer is about to be destroyed, so
1384 * none of the nodes should have any references. The buffer is locked.
1386 * We may be interlocked with the buffer.
1389 hammer_flush_buffer_nodes(hammer_buffer_t buffer
)
1393 while ((node
= TAILQ_FIRST(&buffer
->clist
)) != NULL
) {
1394 KKASSERT(node
->ondisk
== NULL
);
1395 KKASSERT((node
->flags
& HAMMER_NODE_NEEDSCRC
) == 0);
1397 if (node
->lock
.refs
== 0) {
1398 hammer_ref(&node
->lock
);
1399 node
->flags
|= HAMMER_NODE_FLUSH
;
1400 hammer_rel_node(node
);
1402 KKASSERT(node
->loading
!= 0);
1403 KKASSERT(node
->buffer
!= NULL
);
1404 buffer
= node
->buffer
;
1405 node
->buffer
= NULL
;
1406 TAILQ_REMOVE(&buffer
->clist
, node
, entry
);
1407 /* buffer is unreferenced because ondisk is NULL */
1413 /************************************************************************
1415 ************************************************************************/
1418 * Allocate a B-Tree node.
1421 hammer_alloc_btree(hammer_transaction_t trans
, hammer_off_t hint
, int *errorp
)
1423 hammer_buffer_t buffer
= NULL
;
1424 hammer_node_t node
= NULL
;
1425 hammer_off_t node_offset
;
1427 node_offset
= hammer_blockmap_alloc(trans
, HAMMER_ZONE_BTREE_INDEX
,
1428 sizeof(struct hammer_node_ondisk
),
1431 node
= hammer_get_node(trans
, node_offset
, 1, errorp
);
1432 hammer_modify_node_noundo(trans
, node
);
1433 bzero(node
->ondisk
, sizeof(*node
->ondisk
));
1434 hammer_modify_node_done(node
);
1437 hammer_rel_buffer(buffer
, 0);
1442 * Allocate data. If the address of a data buffer is supplied then
1443 * any prior non-NULL *data_bufferp will be released and *data_bufferp
1444 * will be set to the related buffer. The caller must release it when
1445 * finally done. The initial *data_bufferp should be set to NULL by
1448 * The caller is responsible for making hammer_modify*() calls on the
1452 hammer_alloc_data(hammer_transaction_t trans
, int32_t data_len
,
1453 u_int16_t rec_type
, hammer_off_t
*data_offsetp
,
1454 struct hammer_buffer
**data_bufferp
,
1455 hammer_off_t hint
, int *errorp
)
1465 case HAMMER_RECTYPE_INODE
:
1466 case HAMMER_RECTYPE_DIRENTRY
:
1467 case HAMMER_RECTYPE_EXT
:
1468 case HAMMER_RECTYPE_FIX
:
1469 case HAMMER_RECTYPE_PFS
:
1470 zone
= HAMMER_ZONE_META_INDEX
;
1472 case HAMMER_RECTYPE_DATA
:
1473 case HAMMER_RECTYPE_DB
:
1474 if (data_len
<= HAMMER_BUFSIZE
/ 2) {
1475 zone
= HAMMER_ZONE_SMALL_DATA_INDEX
;
1477 data_len
= (data_len
+ HAMMER_BUFMASK
) &
1479 zone
= HAMMER_ZONE_LARGE_DATA_INDEX
;
1483 panic("hammer_alloc_data: rec_type %04x unknown",
1485 zone
= 0; /* NOT REACHED */
1488 *data_offsetp
= hammer_blockmap_alloc(trans
, zone
, data_len
,
1493 if (*errorp
== 0 && data_bufferp
) {
1495 data
= hammer_bread_ext(trans
->hmp
, *data_offsetp
,
1496 data_len
, errorp
, data_bufferp
);
1507 * Sync dirty buffers to the media and clean-up any loose ends.
1509 * These functions do not start the flusher going, they simply
1510 * queue everything up to the flusher.
1512 static int hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
);
1513 static int hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
);
1516 hammer_queue_inodes_flusher(hammer_mount_t hmp
, int waitfor
)
1518 struct hammer_sync_info info
;
1521 info
.waitfor
= waitfor
;
1522 if (waitfor
== MNT_WAIT
) {
1523 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
,
1524 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1526 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_ONEPASS
|VMSC_NOWAIT
,
1527 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1533 * Filesystem sync. If doing a synchronous sync make a second pass on
1534 * the vnodes in case any were already flushing during the first pass,
1535 * and activate the flusher twice (the second time brings the UNDO FIFO's
1536 * start position up to the end position after the first call).
1539 hammer_sync_hmp(hammer_mount_t hmp
, int waitfor
)
1541 struct hammer_sync_info info
;
1544 info
.waitfor
= MNT_NOWAIT
;
1545 vmntvnodescan(hmp
->mp
, VMSC_GETVP
|VMSC_NOWAIT
,
1546 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1547 if (info
.error
== 0 && waitfor
== MNT_WAIT
) {
1548 info
.waitfor
= waitfor
;
1549 vmntvnodescan(hmp
->mp
, VMSC_GETVP
,
1550 hammer_sync_scan1
, hammer_sync_scan2
, &info
);
1552 if (waitfor
== MNT_WAIT
) {
1553 hammer_flusher_sync(hmp
);
1554 hammer_flusher_sync(hmp
);
1556 hammer_flusher_async(hmp
, NULL
);
1557 hammer_flusher_async(hmp
, NULL
);
1563 hammer_sync_scan1(struct mount
*mp
, struct vnode
*vp
, void *data
)
1565 struct hammer_inode
*ip
;
1568 if (vp
->v_type
== VNON
|| ip
== NULL
||
1569 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1570 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1577 hammer_sync_scan2(struct mount
*mp
, struct vnode
*vp
, void *data
)
1579 struct hammer_sync_info
*info
= data
;
1580 struct hammer_inode
*ip
;
1584 if (vp
->v_type
== VNON
|| vp
->v_type
== VBAD
||
1585 ((ip
->flags
& HAMMER_INODE_MODMASK
) == 0 &&
1586 RB_EMPTY(&vp
->v_rbdirty_tree
))) {
1589 error
= VOP_FSYNC(vp
, MNT_NOWAIT
);
1591 info
->error
= error
;