2 * Copyright (c) 2011-2015 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@dragonflybsd.org>
6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * TRANSACTION AND FLUSH HANDLING
38 * Deceptively simple but actually fairly difficult to implement properly is
39 * how I would describe it.
41 * Flushing generally occurs bottom-up but requires a top-down scan to
42 * locate chains with MODIFIED and/or UPDATE bits set. The ONFLUSH flag
43 * tells how to recurse downward to find these chains.
46 #include <sys/cdefs.h>
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/types.h>
57 #define HAMMER2_FLUSH_DEPTH_LIMIT 10 /* stack recursion limit */
61 * Recursively flush the specified chain. The chain is locked and
62 * referenced by the caller and will remain so on return. The chain
63 * will remain referenced throughout but can temporarily lose its
64 * lock during the recursion to avoid unnecessarily stalling user
67 struct hammer2_flush_info
{
68 hammer2_chain_t
*parent
;
73 struct h2_flush_list flushq
;
74 hammer2_chain_t
*debug
;
77 typedef struct hammer2_flush_info hammer2_flush_info_t
;
79 static void hammer2_flush_core(hammer2_flush_info_t
*info
,
80 hammer2_chain_t
*chain
, int flags
);
81 static int hammer2_flush_recurse(hammer2_chain_t
*child
, void *data
);
84 * Any per-pfs transaction initialization goes here.
87 hammer2_trans_manage_init(hammer2_pfs_t
*pmp
)
92 * Transaction support for any modifying operation. Transactions are used
93 * in the pmp layer by the frontend and in the spmp layer by the backend.
95 * 0 - Normal transaction, interlocked against flush
98 * TRANS_ISFLUSH - Flush transaction, interlocked against normal
101 * TRANS_BUFCACHE - Buffer cache transaction, no interlock.
103 * Initializing a new transaction allocates a transaction ID. Typically
104 * passed a pmp (hmp passed as NULL), indicating a cluster transaction. Can
105 * be passed a NULL pmp and non-NULL hmp to indicate a transaction on a single
106 * media target. The latter mode is used by the recovery code.
108 * TWO TRANSACTION IDs can run concurrently, where one is a flush and the
109 * other is a set of any number of concurrent filesystem operations. We
110 * can either have <running_fs_ops> + <waiting_flush> + <blocked_fs_ops>
111 * or we can have <running_flush> + <concurrent_fs_ops>.
113 * During a flush, new fs_ops are only blocked until the fs_ops prior to
114 * the flush complete. The new fs_ops can then run concurrent with the flush.
116 * Buffer-cache transactions operate as fs_ops but never block. A
117 * buffer-cache flush will run either before or after the current pending
118 * flush depending on its state.
121 hammer2_trans_init(hammer2_pfs_t
*pmp
, uint32_t flags
)
128 oflags
= pmp
->trans
.flags
;
132 if (flags
& HAMMER2_TRANS_ISFLUSH
) {
134 * Requesting flush transaction. Wait for all
135 * currently running transactions to finish.
136 * Afterwords, normal transactions will be
139 if (oflags
& HAMMER2_TRANS_MASK
) {
140 nflags
= oflags
| HAMMER2_TRANS_FPENDING
|
141 HAMMER2_TRANS_WAITING
;
144 nflags
= (oflags
| flags
) + 1;
146 } else if (flags
& HAMMER2_TRANS_BUFCACHE
) {
148 * Requesting strategy transaction from buffer-cache,
149 * or a VM getpages/putpages through the buffer cache.
150 * We must allow such transactions in all situations
151 * to avoid deadlocks.
153 nflags
= (oflags
| flags
) + 1;
156 * (old) previous code interlocked against the main
159 if ((oflags
& (HAMMER2_TRANS_ISFLUSH
|
160 HAMMER2_TRANS_PREFLUSH
)) ==
161 HAMMER2_TRANS_ISFLUSH
) {
162 nflags
= oflags
| HAMMER2_TRANS_WAITING
;
165 nflags
= (oflags
| flags
) + 1;
170 * Requesting normal modifying transaction (read-only
171 * operations do not use transactions). Waits for
172 * any flush to finish before allowing. Multiple
173 * modifying transactions can run concurrently.
175 if (oflags
& HAMMER2_TRANS_ISFLUSH
) {
176 nflags
= oflags
| HAMMER2_TRANS_WAITING
;
179 nflags
= (oflags
| flags
) + 1;
183 tsleep_interlock(&pmp
->trans
.sync_wait
, 0);
184 if (atomic_cmpset_int(&pmp
->trans
.flags
, oflags
, nflags
)) {
187 tsleep(&pmp
->trans
.sync_wait
, PINTERLOCKED
,
197 * Start a sub-transaction, there is no 'subdone' function. This will
198 * issue a new modify_tid (mtid) for the current transaction, which is a
199 * CLC (cluster level change) id and not a per-node id.
201 * This function must be called for each XOP when multiple XOPs are run in
202 * sequence within a transaction.
204 * Callers typically update the inode with the transaction mtid manually
205 * to enforce sequencing.
208 hammer2_trans_sub(hammer2_pfs_t
*pmp
)
212 mtid
= atomic_fetchadd_64(&pmp
->modify_tid
, 1);
218 hammer2_trans_done(hammer2_pfs_t
*pmp
)
224 oflags
= pmp
->trans
.flags
;
226 KKASSERT(oflags
& HAMMER2_TRANS_MASK
);
227 if ((oflags
& HAMMER2_TRANS_MASK
) == 1) {
229 * This was the last transaction
231 nflags
= (oflags
- 1) & ~(HAMMER2_TRANS_ISFLUSH
|
232 HAMMER2_TRANS_BUFCACHE
|
233 HAMMER2_TRANS_FPENDING
|
234 HAMMER2_TRANS_WAITING
);
237 * Still transactions pending
241 if (atomic_cmpset_int(&pmp
->trans
.flags
, oflags
, nflags
)) {
242 if ((nflags
& HAMMER2_TRANS_MASK
) == 0 &&
243 (oflags
& HAMMER2_TRANS_WAITING
)) {
244 wakeup(&pmp
->trans
.sync_wait
);
255 * Obtain new, unique inode number (not serialized by caller).
258 hammer2_trans_newinum(hammer2_pfs_t
*pmp
)
262 tid
= atomic_fetchadd_64(&pmp
->inode_tid
, 1);
268 * Assert that a strategy call is ok here. Currently we allow strategy
269 * calls in all situations, including during flushes. Previously:
270 * (old) (1) In a normal transaction.
271 * (old) (2) In a flush transaction only if PREFLUSH is also set.
274 hammer2_trans_assert_strategy(hammer2_pfs_t
*pmp
)
277 KKASSERT((pmp
->trans
.flags
& HAMMER2_TRANS_ISFLUSH
) == 0 ||
278 (pmp
->trans
.flags
& HAMMER2_TRANS_PREFLUSH
));
284 * Chains undergoing destruction are removed from the in-memory topology.
285 * To avoid getting lost these chains are placed on the delayed flush
286 * queue which will properly dispose of them.
288 * We do this instead of issuing an immediate flush in order to give
289 * recursive deletions (rm -rf, etc) a chance to remove more of the
290 * hierarchy, potentially allowing an enormous amount of write I/O to
294 hammer2_delayed_flush(hammer2_chain_t
*chain
)
296 if ((chain
->flags
& HAMMER2_CHAIN_DELAYED
) == 0) {
297 hammer2_spin_ex(&chain
->hmp
->list_spin
);
298 if ((chain
->flags
& (HAMMER2_CHAIN_DELAYED
|
299 HAMMER2_CHAIN_DEFERRED
)) == 0) {
300 atomic_set_int(&chain
->flags
, HAMMER2_CHAIN_DELAYED
|
301 HAMMER2_CHAIN_DEFERRED
);
302 TAILQ_INSERT_TAIL(&chain
->hmp
->flushq
,
304 hammer2_chain_ref(chain
);
306 hammer2_spin_unex(&chain
->hmp
->list_spin
);
307 hammer2_voldata_modify(chain
->hmp
);
312 * Flush the chain and all modified sub-chains through the specified
313 * synchronization point, propagating blockref updates back up. As
314 * part of this propagation, mirror_tid and inode/data usage statistics
315 * propagates back upward.
317 * modify_tid (clc - cluster level change) is not propagated.
319 * update_tid (clc) is used for validation and is not propagated by this
322 * This routine can be called from several places but the most important
323 * is from VFS_SYNC (frontend) via hammer2_inode_xop_flush (backend).
325 * chain is locked on call and will remain locked on return. The chain's
326 * UPDATE flag indicates that its parent's block table (which is not yet
327 * part of the flush) should be updated.
330 hammer2_flush(hammer2_chain_t
*chain
, int flags
)
332 hammer2_chain_t
*scan
;
333 hammer2_flush_info_t info
;
338 * Execute the recursive flush and handle deferrals.
340 * Chains can be ridiculously long (thousands deep), so to
341 * avoid blowing out the kernel stack the recursive flush has a
342 * depth limit. Elements at the limit are placed on a list
343 * for re-execution after the stack has been popped.
345 bzero(&info
, sizeof(info
));
346 TAILQ_INIT(&info
.flushq
);
347 info
.cache_index
= -1;
348 info
.flags
= flags
& ~HAMMER2_FLUSH_TOP
;
351 * Calculate parent (can be NULL), if not NULL the flush core
352 * expects the parent to be referenced so it can easily lock/unlock
353 * it without it getting ripped up.
355 if ((info
.parent
= chain
->parent
) != NULL
)
356 hammer2_chain_ref(info
.parent
);
359 * Extra ref needed because flush_core expects it when replacing
362 hammer2_chain_ref(chain
);
368 * Move hmp->flushq to info.flushq if non-empty so it can
371 if (TAILQ_FIRST(&hmp
->flushq
) != NULL
) {
372 hammer2_spin_ex(&chain
->hmp
->list_spin
);
373 TAILQ_CONCAT(&info
.flushq
, &hmp
->flushq
, flush_node
);
374 hammer2_spin_unex(&chain
->hmp
->list_spin
);
378 * Unwind deep recursions which had been deferred. This
379 * can leave the FLUSH_* bits set for these chains, which
380 * will be handled when we [re]flush chain after the unwind.
382 while ((scan
= TAILQ_FIRST(&info
.flushq
)) != NULL
) {
383 KKASSERT(scan
->flags
& HAMMER2_CHAIN_DEFERRED
);
384 TAILQ_REMOVE(&info
.flushq
, scan
, flush_node
);
385 atomic_clear_int(&scan
->flags
, HAMMER2_CHAIN_DEFERRED
|
386 HAMMER2_CHAIN_DELAYED
);
389 * Now that we've popped back up we can do a secondary
390 * recursion on the deferred elements.
392 * NOTE: hammer2_flush() may replace scan.
394 if (hammer2_debug
& 0x0040)
395 kprintf("deferred flush %p\n", scan
);
396 hammer2_chain_lock(scan
, HAMMER2_RESOLVE_MAYBE
);
397 hammer2_flush(scan
, flags
& ~HAMMER2_FLUSH_TOP
);
398 hammer2_chain_unlock(scan
);
399 hammer2_chain_drop(scan
); /* ref from deferral */
405 info
.diddeferral
= 0;
406 hammer2_flush_core(&info
, chain
, flags
);
409 * Only loop if deep recursions have been deferred.
411 if (TAILQ_EMPTY(&info
.flushq
))
414 if (++loops
% 1000 == 0) {
415 kprintf("hammer2_flush: excessive loops on %p\n",
417 if (hammer2_debug
& 0x100000)
421 hammer2_chain_drop(chain
);
423 hammer2_chain_drop(info
.parent
);
427 * This is the core of the chain flushing code. The chain is locked by the
428 * caller and must also have an extra ref on it by the caller, and remains
429 * locked and will have an extra ref on return. info.parent is referenced
432 * Upon return, the caller can test the UPDATE bit on the chain to determine
433 * if the parent needs updating.
435 * (1) Determine if this node is a candidate for the flush, return if it is
436 * not. fchain and vchain are always candidates for the flush.
438 * (2) If we recurse too deep the chain is entered onto the deferral list and
439 * the current flush stack is aborted until after the deferral list is
442 * (3) Recursively flush live children (rbtree). This can create deferrals.
443 * A successful flush clears the MODIFIED and UPDATE bits on the children
444 * and typically causes the parent to be marked MODIFIED as the children
445 * update the parent's block table. A parent might already be marked
446 * MODIFIED due to a deletion (whos blocktable update in the parent is
447 * handled by the frontend), or if the parent itself is modified by the
448 * frontend for other reasons.
450 * (4) Permanently disconnected sub-trees are cleaned up by the front-end.
451 * Deleted-but-open inodes can still be individually flushed via the
454 * (5) Delete parents on the way back up if they are normal indirect blocks
455 * and have no children.
457 * (6) Note that an unmodified child may still need the block table in its
458 * parent updated (e.g. rename/move). The child will have UPDATE set
461 * WARNING ON BREF MODIFY_TID/MIRROR_TID
463 * blockref.modify_tid is consistent only within a PFS, and will not be
464 * consistent during synchronization. mirror_tid is consistent across the
465 * block device regardless of the PFS.
468 hammer2_flush_core(hammer2_flush_info_t
*info
, hammer2_chain_t
*chain
,
471 hammer2_chain_t
*parent
;
476 * (1) Optimize downward recursion to locate nodes needing action.
477 * Nothing to do if none of these flags are set.
479 if ((chain
->flags
& HAMMER2_CHAIN_FLUSH_MASK
) == 0) {
480 if (hammer2_debug
& 0x200) {
481 if (info
->debug
== NULL
)
489 diddeferral
= info
->diddeferral
;
490 parent
= info
->parent
; /* can be NULL */
491 KKASSERT(chain
->parent
== parent
);
494 * Downward search recursion
496 if (chain
->flags
& (HAMMER2_CHAIN_DEFERRED
| HAMMER2_CHAIN_DELAYED
)) {
501 } else if ((chain
->flags
& HAMMER2_CHAIN_PFSBOUNDARY
) &&
502 (flags
& HAMMER2_FLUSH_ALL
) == 0 &&
503 (flags
& HAMMER2_FLUSH_TOP
) == 0) {
505 * If FLUSH_ALL is not specified the caller does not want
506 * to recurse through PFS roots. The typical sequence is
507 * to flush dirty PFS's starting at their root downward,
508 * then flush the device root (vchain). It is this second
509 * flush that typically leaves out the ALL flag.
511 * However we must still process the PFSROOT chains for block
512 * table updates in their parent (which IS part of our flush).
514 * NOTE: The volume root, vchain, does not set PFSBOUNDARY.
516 * NOTE: This test must be done before the depth-limit test,
517 * else it might become the top on a flushq iteration.
519 * NOTE: We must re-set ONFLUSH in the parent to retain if
520 * this chain (that we are skipping) requires work.
522 if (chain
->flags
& (HAMMER2_CHAIN_ONFLUSH
|
523 HAMMER2_CHAIN_DESTROY
|
524 HAMMER2_CHAIN_MODIFIED
)) {
525 hammer2_chain_setflush(parent
);
527 } else if (info
->depth
== HAMMER2_FLUSH_DEPTH_LIMIT
) {
529 * Recursion depth reached.
531 KKASSERT((chain
->flags
& HAMMER2_CHAIN_DELAYED
) == 0);
532 hammer2_chain_ref(chain
);
533 TAILQ_INSERT_TAIL(&info
->flushq
, chain
, flush_node
);
534 atomic_set_int(&chain
->flags
, HAMMER2_CHAIN_DEFERRED
);
536 } else if (chain
->flags
& (HAMMER2_CHAIN_ONFLUSH
|
537 HAMMER2_CHAIN_DESTROY
)) {
539 * Downward recursion search (actual flush occurs bottom-up).
540 * pre-clear ONFLUSH. It can get set again due to races,
541 * which we want so the scan finds us again in the next flush.
543 * We must also recurse if DESTROY is set so we can finally
544 * get rid of the related children, otherwise the node will
545 * just get re-flushed on lastdrop.
547 * WARNING! The recursion will unlock/relock info->parent
548 * (which is 'chain'), potentially allowing it
551 atomic_clear_int(&chain
->flags
, HAMMER2_CHAIN_ONFLUSH
);
552 info
->parent
= chain
;
553 hammer2_spin_ex(&chain
->core
.spin
);
554 RB_SCAN(hammer2_chain_tree
, &chain
->core
.rbtree
,
555 NULL
, hammer2_flush_recurse
, info
);
556 hammer2_spin_unex(&chain
->core
.spin
);
557 info
->parent
= parent
;
558 if (info
->diddeferral
)
559 hammer2_chain_setflush(chain
);
562 * If we lost the parent->chain association we have to
563 * stop processing this chain because it is no longer
564 * in this recursion. If it moved, it will be handled
565 * by the ONFLUSH flag elsewhere.
567 if (chain
->parent
!= parent
) {
568 kprintf("LOST CHILD2 %p->%p (actual parent %p)\n",
569 parent
, chain
, chain
->parent
);
575 * Now we are in the bottom-up part of the recursion.
577 * Do not update chain if lower layers were deferred.
579 if (info
->diddeferral
)
583 * Both parent and chain must be locked in order to flush chain,
584 * in order to properly update the parent under certain conditions.
586 * In addition, we can't safely unlock/relock the chain once we
587 * start flushing the chain itself, which we would have to do later
588 * on in order to lock the parent if we didn't do that now.
590 hammer2_chain_unlock(chain
);
592 hammer2_chain_lock(parent
, HAMMER2_RESOLVE_ALWAYS
);
593 hammer2_chain_lock(chain
, HAMMER2_RESOLVE_MAYBE
);
594 if (chain
->parent
!= parent
) {
595 kprintf("LOST CHILD3 %p->%p (actual parent %p)\n",
596 parent
, chain
, chain
->parent
);
597 KKASSERT(parent
!= NULL
);
598 hammer2_chain_unlock(parent
);
599 if ((chain
->flags
& HAMMER2_CHAIN_DELAYED
) == 0) {
600 hammer2_chain_ref(chain
);
601 TAILQ_INSERT_TAIL(&info
->flushq
, chain
, flush_node
);
602 atomic_set_int(&chain
->flags
, HAMMER2_CHAIN_DEFERRED
);
609 * Propagate the DESTROY flag downwards. This dummies up the flush
610 * code and tries to invalidate related buffer cache buffers to
611 * avoid the disk write.
613 if (parent
&& (parent
->flags
& HAMMER2_CHAIN_DESTROY
))
614 atomic_set_int(&chain
->flags
, HAMMER2_CHAIN_DESTROY
);
617 * Chain was already modified or has become modified, flush it out.
619 if ((hammer2_debug
& 0x200) &&
621 (chain
->flags
& (HAMMER2_CHAIN_MODIFIED
| HAMMER2_CHAIN_UPDATE
))) {
622 hammer2_chain_t
*scan
= chain
;
624 kprintf("DISCONNECTED FLUSH %p->%p\n", info
->debug
, chain
);
626 kprintf(" chain %p [%08x] bref=%016jx:%02x\n",
628 scan
->bref
.key
, scan
->bref
.type
);
629 if (scan
== info
->debug
)
635 if (chain
->flags
& HAMMER2_CHAIN_MODIFIED
) {
637 * Dispose of the modified bit.
639 * If parent is present, the UPDATE bit should already be set.
640 * UPDATE should already be set.
641 * bref.mirror_tid should already be set.
643 KKASSERT((chain
->flags
& HAMMER2_CHAIN_UPDATE
) ||
644 chain
->parent
== NULL
);
645 if (hammer2_debug
& 0x800000) {
648 for (pp
= chain
; pp
->parent
; pp
= pp
->parent
)
650 kprintf("FLUSH CHAIN %p (p=%p pp=%p/%d) TYPE %d FLAGS %08x (%s)\n",
651 chain
, chain
->parent
, pp
, pp
->bref
.type
,
652 chain
->bref
.type
, chain
->flags
,
653 (chain
->bref
.type
== 1 ? (const char *)chain
->data
->ipdata
.filename
: "?")
658 atomic_clear_int(&chain
->flags
, HAMMER2_CHAIN_MODIFIED
);
659 atomic_add_long(&hammer2_count_modified_chains
, -1);
662 * Manage threads waiting for excessive dirty memory to
666 hammer2_pfs_memory_wakeup(chain
->pmp
);
669 if ((chain
->flags
& HAMMER2_CHAIN_UPDATE
) == 0 &&
670 chain
!= &hmp
->vchain
&&
671 chain
!= &hmp
->fchain
) {
673 * Set UPDATE bit indicating that the parent block
674 * table requires updating.
676 atomic_set_int(&chain
->flags
, HAMMER2_CHAIN_UPDATE
);
681 * Issue the flush. This is indirect via the DIO.
683 * NOTE: A DELETED node that reaches this point must be
684 * flushed for synchronization point consistency.
686 * NOTE: Even though MODIFIED was already set, the related DIO
687 * might not be dirty due to a system buffer cache
688 * flush and must be set dirty if we are going to make
689 * further modifications to the buffer. Chains with
690 * embedded data don't need this.
692 if (hammer2_debug
& 0x1000) {
693 kprintf("Flush %p.%d %016jx/%d data=%016jx\n",
694 chain
, chain
->bref
.type
,
695 (uintmax_t)chain
->bref
.key
,
697 (uintmax_t)chain
->bref
.data_off
);
699 if (hammer2_debug
& 0x2000) {
700 Debugger("Flush hell");
704 * Update chain CRCs for flush.
706 * NOTE: Volume headers are NOT flushed here as they require
707 * special processing.
709 switch(chain
->bref
.type
) {
710 case HAMMER2_BREF_TYPE_FREEMAP
:
712 * Update the volume header's freemap_tid to the
713 * freemap's flushing mirror_tid.
715 * (note: embedded data, do not call setdirty)
717 KKASSERT(hmp
->vchain
.flags
& HAMMER2_CHAIN_MODIFIED
);
718 KKASSERT(chain
== &hmp
->fchain
);
719 hmp
->voldata
.freemap_tid
= chain
->bref
.mirror_tid
;
720 if (hammer2_debug
& 0x8000) {
721 /* debug only, avoid syslogd loop */
722 kprintf("sync freemap mirror_tid %08jx\n",
723 (intmax_t)chain
->bref
.mirror_tid
);
727 * The freemap can be flushed independently of the
728 * main topology, but for the case where it is
729 * flushed in the same transaction, and flushed
730 * before vchain (a case we want to allow for
731 * performance reasons), make sure modifications
732 * made during the flush under vchain use a new
735 * Otherwise the mount recovery code will get confused.
737 ++hmp
->voldata
.mirror_tid
;
739 case HAMMER2_BREF_TYPE_VOLUME
:
741 * The free block table is flushed by
742 * hammer2_vfs_sync() before it flushes vchain.
743 * We must still hold fchain locked while copying
744 * voldata to volsync, however.
746 * (note: embedded data, do not call setdirty)
748 hammer2_chain_lock(&hmp
->fchain
,
749 HAMMER2_RESOLVE_ALWAYS
);
750 hammer2_voldata_lock(hmp
);
751 if (hammer2_debug
& 0x8000) {
752 /* debug only, avoid syslogd loop */
753 kprintf("sync volume mirror_tid %08jx\n",
754 (intmax_t)chain
->bref
.mirror_tid
);
758 * Update the volume header's mirror_tid to the
759 * main topology's flushing mirror_tid. It is
760 * possible that voldata.mirror_tid is already
761 * beyond bref.mirror_tid due to the bump we made
762 * above in BREF_TYPE_FREEMAP.
764 if (hmp
->voldata
.mirror_tid
< chain
->bref
.mirror_tid
) {
765 hmp
->voldata
.mirror_tid
=
766 chain
->bref
.mirror_tid
;
770 * The volume header is flushed manually by the
771 * syncer, not here. All we do here is adjust the
774 KKASSERT(chain
->data
!= NULL
);
775 KKASSERT(chain
->dio
== NULL
);
777 hmp
->voldata
.icrc_sects
[HAMMER2_VOL_ICRC_SECT1
]=
779 (char *)&hmp
->voldata
+
780 HAMMER2_VOLUME_ICRC1_OFF
,
781 HAMMER2_VOLUME_ICRC1_SIZE
);
782 hmp
->voldata
.icrc_sects
[HAMMER2_VOL_ICRC_SECT0
]=
784 (char *)&hmp
->voldata
+
785 HAMMER2_VOLUME_ICRC0_OFF
,
786 HAMMER2_VOLUME_ICRC0_SIZE
);
787 hmp
->voldata
.icrc_volheader
=
789 (char *)&hmp
->voldata
+
790 HAMMER2_VOLUME_ICRCVH_OFF
,
791 HAMMER2_VOLUME_ICRCVH_SIZE
);
793 if (hammer2_debug
& 0x8000) {
794 /* debug only, avoid syslogd loop */
795 kprintf("syncvolhdr %016jx %016jx\n",
796 hmp
->voldata
.mirror_tid
,
797 hmp
->vchain
.bref
.mirror_tid
);
799 hmp
->volsync
= hmp
->voldata
;
800 atomic_set_int(&chain
->flags
, HAMMER2_CHAIN_VOLUMESYNC
);
801 hammer2_voldata_unlock(hmp
);
802 hammer2_chain_unlock(&hmp
->fchain
);
804 case HAMMER2_BREF_TYPE_DATA
:
806 * Data elements have already been flushed via the
807 * logical file buffer cache. Their hash was set in
808 * the bref by the vop_write code. Do not re-dirty.
810 * Make sure any device buffer(s) have been flushed
811 * out here (there aren't usually any to flush) XXX.
814 case HAMMER2_BREF_TYPE_INDIRECT
:
815 case HAMMER2_BREF_TYPE_FREEMAP_NODE
:
816 case HAMMER2_BREF_TYPE_FREEMAP_LEAF
:
818 * Buffer I/O will be cleaned up when the volume is
819 * flushed (but the kernel is free to flush it before
822 KKASSERT((chain
->flags
& HAMMER2_CHAIN_EMBEDDED
) == 0);
823 hammer2_chain_setcheck(chain
, chain
->data
);
825 case HAMMER2_BREF_TYPE_DIRENT
:
827 * A directory entry can use the check area to store
828 * the filename for filenames <= 64 bytes, don't blow
831 KKASSERT((chain
->flags
& HAMMER2_CHAIN_EMBEDDED
) == 0);
833 hammer2_chain_setcheck(chain
, chain
->data
);
835 case HAMMER2_BREF_TYPE_INODE
:
837 * NOTE: We must call io_setdirty() to make any late
838 * changes to the inode data, the system might
839 * have already flushed the buffer.
841 if (chain
->data
->ipdata
.meta
.op_flags
&
842 HAMMER2_OPFLAG_PFSROOT
) {
844 * non-NULL pmp if mounted as a PFS. We must
845 * sync fields cached in the pmp? XXX
847 hammer2_inode_data_t
*ipdata
;
849 hammer2_io_setdirty(chain
->dio
);
850 ipdata
= &chain
->data
->ipdata
;
852 ipdata
->meta
.pfs_inum
=
853 chain
->pmp
->inode_tid
;
856 /* can't be mounted as a PFS */
859 KKASSERT((chain
->flags
& HAMMER2_CHAIN_EMBEDDED
) == 0);
860 hammer2_chain_setcheck(chain
, chain
->data
);
863 KKASSERT(chain
->flags
& HAMMER2_CHAIN_EMBEDDED
);
864 panic("hammer2_flush_core: unsupported "
871 * If the chain was destroyed try to avoid unnecessary I/O
872 * that might not have yet occurred. Remove the data range
873 * from dedup candidacy and attempt to invalidation that
874 * potentially dirty portion of the I/O buffer.
876 if (chain
->flags
& HAMMER2_CHAIN_DESTROY
) {
877 hammer2_io_dedup_delete(hmp
,
879 chain
->bref
.data_off
,
884 hammer2_io_inval(chain
->dio
,
885 chain
->bref
.data_off
,
887 } else if ((dio
= hammer2_io_getquick(hmp
,
888 chain
->bref
.data_off
,
891 hammer2_io_inval(dio
,
892 chain
->bref
.data_off
,
894 hammer2_io_putblk(&dio
);
901 * If UPDATE is set the parent block table may need to be updated.
903 * NOTE: UPDATE may be set on vchain or fchain in which case
904 * parent could be NULL. It's easiest to allow the case
905 * and test for NULL. parent can also wind up being NULL
906 * due to a deletion so we need to handle the case anyway.
908 * If no parent exists we can just clear the UPDATE bit. If the
909 * chain gets reattached later on the bit will simply get set
912 if ((chain
->flags
& HAMMER2_CHAIN_UPDATE
) && parent
== NULL
)
913 atomic_clear_int(&chain
->flags
, HAMMER2_CHAIN_UPDATE
);
916 * The chain may need its blockrefs updated in the parent.
918 if (chain
->flags
& HAMMER2_CHAIN_UPDATE
) {
919 hammer2_blockref_t
*base
;
923 * Clear UPDATE flag, mark parent modified, update its
924 * modify_tid if necessary, and adjust the parent blockmap.
926 if (chain
->flags
& HAMMER2_CHAIN_UPDATE
)
927 atomic_clear_int(&chain
->flags
, HAMMER2_CHAIN_UPDATE
);
932 * Avoid actually modifying and updating the parent if it
933 * was flagged for destruction. This can greatly reduce
934 * disk I/O in large tree removals because the
935 * hammer2_io_setinval() call in the upward recursion
936 * (see MODIFIED code above) can only handle a few cases.
938 if (parent
->flags
& HAMMER2_CHAIN_DESTROY
) {
939 if (parent
->bref
.modify_tid
< chain
->bref
.modify_tid
) {
940 parent
->bref
.modify_tid
=
941 chain
->bref
.modify_tid
;
943 atomic_clear_int(&chain
->flags
, HAMMER2_CHAIN_BMAPPED
|
944 HAMMER2_CHAIN_BMAPUPD
);
949 * (semi-optional code)
951 * The flusher is responsible for deleting empty indirect
952 * blocks at this point. If we don't do this, no major harm
953 * will be done but the empty indirect blocks will stay in
954 * the topology and make it a bit messy.
956 if (chain
->bref
.type
== HAMMER2_BREF_TYPE_INDIRECT
&&
957 chain
->core
.live_count
== 0 &&
958 (chain
->flags
& (HAMMER2_CHAIN_INITIAL
|
959 HAMMER2_CHAIN_COUNTEDBREFS
)) == 0) {
960 base
= &chain
->data
->npdata
[0];
961 count
= chain
->bytes
/ sizeof(hammer2_blockref_t
);
962 hammer2_chain_countbrefs(chain
, base
, count
);
964 if (chain
->bref
.type
== HAMMER2_BREF_TYPE_INDIRECT
&&
965 chain
->core
.live_count
== 0) {
967 kprintf("DELETE CHAIN %016jx.%02x %016jx/%d refs=%d\n",
968 chain
->bref
.data_off
, chain
->bref
.type
,
969 chain
->bref
.key
, chain
->bref
.keybits
,
972 hammer2_chain_delete(parent
, chain
,
973 chain
->bref
.modify_tid
,
974 HAMMER2_DELETE_PERMANENT
);
979 * We are updating the parent's blockmap, the parent must
982 hammer2_chain_modify(parent
, 0, 0, 0);
983 if (parent
->bref
.modify_tid
< chain
->bref
.modify_tid
)
984 parent
->bref
.modify_tid
= chain
->bref
.modify_tid
;
987 * Calculate blockmap pointer
989 switch(parent
->bref
.type
) {
990 case HAMMER2_BREF_TYPE_INODE
:
992 * Access the inode's block array. However, there is
993 * no block array if the inode is flagged DIRECTDATA.
996 (parent
->data
->ipdata
.meta
.op_flags
&
997 HAMMER2_OPFLAG_DIRECTDATA
) == 0) {
998 base
= &parent
->data
->
999 ipdata
.u
.blockset
.blockref
[0];
1003 count
= HAMMER2_SET_COUNT
;
1005 case HAMMER2_BREF_TYPE_INDIRECT
:
1006 case HAMMER2_BREF_TYPE_FREEMAP_NODE
:
1008 base
= &parent
->data
->npdata
[0];
1011 count
= parent
->bytes
/ sizeof(hammer2_blockref_t
);
1013 case HAMMER2_BREF_TYPE_VOLUME
:
1014 base
= &chain
->hmp
->voldata
.sroot_blockset
.blockref
[0];
1015 count
= HAMMER2_SET_COUNT
;
1017 case HAMMER2_BREF_TYPE_FREEMAP
:
1018 base
= &parent
->data
->npdata
[0];
1019 count
= HAMMER2_SET_COUNT
;
1024 panic("hammer2_flush_core: "
1025 "unrecognized blockref type: %d",
1030 * Blocktable updates
1032 * We synchronize pending statistics at this time. Delta
1033 * adjustments designated for the current and upper level
1036 if (base
&& (chain
->flags
& HAMMER2_CHAIN_BMAPUPD
)) {
1037 if (chain
->flags
& HAMMER2_CHAIN_BMAPPED
) {
1038 hammer2_spin_ex(&parent
->core
.spin
);
1039 hammer2_base_delete(parent
, base
, count
,
1040 &info
->cache_index
, chain
);
1041 hammer2_spin_unex(&parent
->core
.spin
);
1042 /* base_delete clears both bits */
1044 atomic_clear_int(&chain
->flags
,
1045 HAMMER2_CHAIN_BMAPUPD
);
1048 if (base
&& (chain
->flags
& HAMMER2_CHAIN_BMAPPED
) == 0) {
1049 hammer2_spin_ex(&parent
->core
.spin
);
1050 hammer2_base_insert(parent
, base
, count
,
1051 &info
->cache_index
, chain
);
1052 hammer2_spin_unex(&parent
->core
.spin
);
1053 /* base_insert sets BMAPPED */
1058 hammer2_chain_unlock(parent
);
1061 * Final cleanup after flush
1064 KKASSERT(chain
->refs
> 0);
1065 if (hammer2_debug
& 0x200) {
1066 if (info
->debug
== chain
)
1072 * Flush recursion helper, called from flush_core, calls flush_core.
1074 * Flushes the children of the caller's chain (info->parent), restricted
1075 * by sync_tid. Set info->domodify if the child's blockref must propagate
1076 * back up to the parent.
1078 * Ripouts can move child from rbtree to dbtree or dbq but the caller's
1079 * flush scan order prevents any chains from being lost. A child can be
1080 * executes more than once.
1082 * WARNING! If we do not call hammer2_flush_core() we must update
1083 * bref.mirror_tid ourselves to indicate that the flush has
1084 * processed the child.
1086 * WARNING! parent->core spinlock is held on entry and return.
1089 hammer2_flush_recurse(hammer2_chain_t
*child
, void *data
)
1091 hammer2_flush_info_t
*info
= data
;
1092 hammer2_chain_t
*parent
= info
->parent
;
1095 * (child can never be fchain or vchain so a special check isn't
1098 * We must ref the child before unlocking the spinlock.
1100 * The caller has added a ref to the parent so we can temporarily
1101 * unlock it in order to lock the child. However, if it no longer
1102 * winds up being the child of the parent we must skip this child.
1104 hammer2_chain_ref(child
);
1105 hammer2_spin_unex(&parent
->core
.spin
);
1107 hammer2_chain_unlock(parent
);
1108 hammer2_chain_lock(child
, HAMMER2_RESOLVE_MAYBE
);
1109 if (child
->parent
!= parent
) {
1110 kprintf("LOST CHILD1 %p->%p (actual parent %p)\n",
1111 parent
, child
, child
->parent
);
1116 * Must propagate the DESTROY flag downwards, otherwise the
1117 * parent could end up never being removed because it will
1118 * be requeued to the flusher if it survives this run due to
1121 if (parent
&& (parent
->flags
& HAMMER2_CHAIN_DESTROY
))
1122 atomic_set_int(&child
->flags
, HAMMER2_CHAIN_DESTROY
);
1125 * Recurse and collect deferral data. We're in the media flush,
1126 * this can cross PFS boundaries.
1128 if (child
->flags
& HAMMER2_CHAIN_FLUSH_MASK
) {
1130 hammer2_flush_core(info
, child
, info
->flags
);
1132 } else if (hammer2_debug
& 0x200) {
1133 if (info
->debug
== NULL
)
1134 info
->debug
= child
;
1136 hammer2_flush_core(info
, child
, info
->flags
);
1138 if (info
->debug
== child
)
1144 * Relock to continue the loop
1146 hammer2_chain_unlock(child
);
1147 hammer2_chain_lock(parent
, HAMMER2_RESOLVE_MAYBE
);
1148 hammer2_chain_drop(child
);
1149 KKASSERT(info
->parent
== parent
);
1150 hammer2_spin_ex(&parent
->core
.spin
);
1157 * Flush helper (direct)
1159 * Quickly flushes any dirty chains for a device and returns a temporary
1160 * out-of-band copy of hmp->vchain that the caller can use as a stable
1163 * This function does not flush the actual volume root and does not flush dirty
1164 * device buffers. We don't care about pending work, per-say. This function
1165 * is primarily used by the bulkfree code to create a stable snapshot of
1169 hammer2_flush_quick(hammer2_dev_t
*hmp
)
1171 hammer2_chain_t
*chain
;
1172 hammer2_chain_t
*copy
;
1174 hammer2_trans_init(hmp
->spmp
, HAMMER2_TRANS_ISFLUSH
);
1176 hammer2_chain_ref(&hmp
->vchain
);
1177 hammer2_chain_lock(&hmp
->vchain
, HAMMER2_RESOLVE_ALWAYS
);
1178 if (hmp
->vchain
.flags
& HAMMER2_CHAIN_FLUSH_MASK
) {
1179 chain
= &hmp
->vchain
;
1180 hammer2_flush(chain
, HAMMER2_FLUSH_TOP
|
1182 KKASSERT(chain
== &hmp
->vchain
);
1184 copy
= hammer2_chain_bulksnap(&hmp
->vchain
);
1185 hammer2_chain_unlock(&hmp
->vchain
);
1186 hammer2_chain_drop(&hmp
->vchain
);
1188 hammer2_trans_done(hmp
->spmp
); /* spmp trans */
1195 * flush helper (backend threaded)
1197 * Flushes core chains, issues disk sync, flushes volume roots.
1199 * Primarily called from vfs_sync().
1202 hammer2_inode_xop_flush(hammer2_thread_t
*thr
, hammer2_xop_t
*arg
)
1204 hammer2_xop_flush_t
*xop
= &arg
->xop_flush
;
1205 hammer2_chain_t
*chain
;
1206 hammer2_chain_t
*parent
;
1209 int total_error
= 0;
1215 chain
= hammer2_inode_chain(xop
->head
.ip1
, thr
->clindex
,
1216 HAMMER2_RESOLVE_ALWAYS
);
1219 if ((chain
->flags
& HAMMER2_CHAIN_FLUSH_MASK
) ||
1220 TAILQ_FIRST(&hmp
->flushq
) != NULL
) {
1221 hammer2_flush(chain
, HAMMER2_FLUSH_TOP
);
1222 parent
= chain
->parent
;
1223 KKASSERT(chain
->pmp
!= parent
->pmp
);
1224 hammer2_chain_setflush(parent
);
1226 hammer2_chain_unlock(chain
);
1227 hammer2_chain_drop(chain
);
1234 * Flush volume roots. Avoid replication, we only want to
1235 * flush each hammer2_dev (hmp) once.
1237 for (j
= thr
->clindex
- 1; j
>= 0; --j
) {
1238 if ((chain
= xop
->head
.ip1
->cluster
.array
[j
].chain
) != NULL
) {
1239 if (chain
->hmp
== hmp
) {
1240 chain
= NULL
; /* safety */
1245 chain
= NULL
; /* safety */
1248 * spmp transaction. The super-root is never directly mounted so
1249 * there shouldn't be any vnodes, let alone any dirty vnodes
1250 * associated with it, so we shouldn't have to mess around with any
1251 * vnode flushes here.
1253 hammer2_trans_init(hmp
->spmp
, HAMMER2_TRANS_ISFLUSH
);
1256 * Media mounts have two 'roots', vchain for the topology
1257 * and fchain for the free block table. Flush both.
1259 * Note that the topology and free block table are handled
1260 * independently, so the free block table can wind up being
1261 * ahead of the topology. We depend on the bulk free scan
1262 * code to deal with any loose ends.
1264 hammer2_chain_ref(&hmp
->vchain
);
1265 hammer2_chain_lock(&hmp
->vchain
, HAMMER2_RESOLVE_ALWAYS
);
1266 hammer2_chain_ref(&hmp
->fchain
);
1267 hammer2_chain_lock(&hmp
->fchain
, HAMMER2_RESOLVE_ALWAYS
);
1268 if (hmp
->fchain
.flags
& HAMMER2_CHAIN_FLUSH_MASK
) {
1270 * This will also modify vchain as a side effect,
1271 * mark vchain as modified now.
1273 hammer2_voldata_modify(hmp
);
1274 chain
= &hmp
->fchain
;
1275 hammer2_flush(chain
, HAMMER2_FLUSH_TOP
);
1276 KKASSERT(chain
== &hmp
->fchain
);
1278 hammer2_chain_unlock(&hmp
->fchain
);
1279 hammer2_chain_unlock(&hmp
->vchain
);
1280 hammer2_chain_drop(&hmp
->fchain
);
1281 /* vchain dropped down below */
1283 hammer2_chain_lock(&hmp
->vchain
, HAMMER2_RESOLVE_ALWAYS
);
1284 if (hmp
->vchain
.flags
& HAMMER2_CHAIN_FLUSH_MASK
) {
1285 chain
= &hmp
->vchain
;
1286 hammer2_flush(chain
, HAMMER2_FLUSH_TOP
);
1287 KKASSERT(chain
== &hmp
->vchain
);
1289 hammer2_chain_unlock(&hmp
->vchain
);
1290 hammer2_chain_drop(&hmp
->vchain
);
1295 * We can't safely flush the volume header until we have
1296 * flushed any device buffers which have built up.
1298 * XXX this isn't being incremental
1300 vn_lock(hmp
->devvp
, LK_EXCLUSIVE
| LK_RETRY
);
1301 error
= VOP_FSYNC(hmp
->devvp
, MNT_WAIT
, 0);
1302 vn_unlock(hmp
->devvp
);
1305 * The flush code sets CHAIN_VOLUMESYNC to indicate that the
1306 * volume header needs synchronization via hmp->volsync.
1308 * XXX synchronize the flag & data with only this flush XXX
1311 (hmp
->vchain
.flags
& HAMMER2_CHAIN_VOLUMESYNC
)) {
1315 * Synchronize the disk before flushing the volume
1319 bp
->b_bio1
.bio_offset
= 0;
1322 bp
->b_cmd
= BUF_CMD_FLUSH
;
1323 bp
->b_bio1
.bio_done
= biodone_sync
;
1324 bp
->b_bio1
.bio_flags
|= BIO_SYNC
;
1325 vn_strategy(hmp
->devvp
, &bp
->b_bio1
);
1326 biowait(&bp
->b_bio1
, "h2vol");
1330 * Then we can safely flush the version of the
1331 * volume header synchronized by the flush code.
1333 j
= hmp
->volhdrno
+ 1;
1334 if (j
>= HAMMER2_NUM_VOLHDRS
)
1336 if (j
* HAMMER2_ZONE_BYTES64
+ HAMMER2_SEGSIZE
>
1337 hmp
->volsync
.volu_size
) {
1340 if (hammer2_debug
& 0x8000) {
1341 /* debug only, avoid syslogd loop */
1342 kprintf("sync volhdr %d %jd\n",
1343 j
, (intmax_t)hmp
->volsync
.volu_size
);
1345 bp
= getblk(hmp
->devvp
, j
* HAMMER2_ZONE_BYTES64
,
1346 HAMMER2_PBUFSIZE
, 0, 0);
1347 atomic_clear_int(&hmp
->vchain
.flags
,
1348 HAMMER2_CHAIN_VOLUMESYNC
);
1349 bcopy(&hmp
->volsync
, bp
->b_data
, HAMMER2_PBUFSIZE
);
1354 total_error
= error
;
1356 hammer2_trans_done(hmp
->spmp
); /* spmp trans */
1358 error
= hammer2_xop_feed(&xop
->head
, NULL
, thr
->clindex
, total_error
);