2 * Copyright (c) 2011-2013 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 * This subsystem implements most of the core support functions for
37 * the hammer2_chain structure.
39 * Chains are the in-memory version on media objects (volume header, inodes,
40 * indirect blocks, data blocks, etc). Chains represent a portion of the
43 * A chain is topologically stable once it has been inserted into the
44 * in-memory topology. Modifications which copy, move, or resize the chain
45 * are handled via the DELETE-DUPLICATE mechanic where the original chain
46 * stays intact but is marked deleted and a new chain is allocated which
47 * shares the old chain's children.
49 * This sharing is handled via the hammer2_chain_core structure.
51 * The DELETE-DUPLICATE mechanism allows the same topological level to contain
52 * many overloadings. However, our RBTREE mechanics require that there be
53 * no overlaps so we accomplish the overloading by moving conflicting chains
54 * with smaller or equal radii into a sub-RBTREE under the chain being
57 * DELETE-DUPLICATE is also used when a modification to a chain crosses a
58 * flush synchronization boundary, allowing the flush code to continue flushing
59 * the older version of the topology and not be disrupted by new frontend
64 * All lookup and iterate operations and most modifications are done on the
65 * live view. During flushes lookups are not normally done and modifications
66 * may be run on the flush view. However, flushes often needs to allocate
67 * blocks and the freemap_alloc/free code issues lookups. This code is
68 * special cased to use the live view when called from a flush.
70 * General chain lookup/iteration functions are NOT aware of the flush view,
71 * they only know about live views.
73 #include <sys/cdefs.h>
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/types.h>
78 #include <sys/kern_syscall.h>
83 static int hammer2_indirect_optimize; /* XXX SYSCTL */
85 static hammer2_chain_t *hammer2_chain_create_indirect(
86 hammer2_trans_t *trans, hammer2_chain_t *parent,
87 hammer2_key_t key, int keybits, int for_type, int *errorp);
88 static void hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop);
89 static void adjreadcounter(hammer2_blockref_t *bref, size_t bytes);
90 static hammer2_chain_t *hammer2_combined_find(
91 hammer2_chain_t *parent,
92 hammer2_blockref_t *base, int count,
93 int *cache_indexp, hammer2_key_t *key_nextp,
94 hammer2_key_t key_beg, hammer2_key_t key_end,
95 hammer2_blockref_t **bresp);
98 * Basic RBTree for chains. Chains cannot overlap within any given
99 * core->rbtree without recursing through chain->rbtree. We effectively
100 * guarantee this by checking the full range rather than just the first
101 * key element. By matching on the full range callers can detect when
102 * recursrion through chain->rbtree is needed.
104 * NOTE: This also means the a delete-duplicate on the same key will
105 * overload by placing the deleted element in the new element's
106 * chain->rbtree (when doing a direct replacement).
108 RB_GENERATE(hammer2_chain_tree, hammer2_chain, rbnode, hammer2_chain_cmp);
111 hammer2_chain_cmp(hammer2_chain_t *chain1, hammer2_chain_t *chain2)
113 hammer2_key_t c1_beg;
114 hammer2_key_t c1_end;
115 hammer2_key_t c2_beg;
116 hammer2_key_t c2_end;
118 c1_beg = chain1->bref.key;
119 c1_end = c1_beg + ((hammer2_key_t)1 << chain1->bref.keybits) - 1;
120 c2_beg = chain2->bref.key;
121 c2_end = c2_beg + ((hammer2_key_t)1 << chain2->bref.keybits) - 1;
123 if (c1_end < c2_beg) /* fully to the left */
125 if (c1_beg > c2_end) /* fully to the right */
127 return(0); /* overlap (must not cross edge boundary) */
132 hammer2_isclusterable(hammer2_chain_t *chain)
134 if (hammer2_cluster_enable) {
135 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
136 chain->bref.type == HAMMER2_BREF_TYPE_INODE ||
137 chain->bref.type == HAMMER2_BREF_TYPE_DATA) {
145 * Recursively set the update_hi flag up to the root starting at chain's
146 * parent->core. update_hi is not set in chain's core.
148 * This controls top-down visibility for flushes. The child has just one
149 * 'above' core, but the core itself can be multi-homed with parents iterated
152 * This function is not used during a flush (except when the flush is
153 * allocating which requires the live tree). The flush keeps track of its
156 * XXX needs to be optimized to use roll-up TIDs. update_hi is only really
157 * compared against bref.mirror_tid which itself is only updated by a flush.
160 hammer2_chain_setsubmod(hammer2_trans_t *trans, hammer2_chain_t *chain)
162 hammer2_chain_core_t *above;
166 (HAMMER2_TRANS_ISFLUSH | HAMMER2_TRANS_ISALLOCATING)) ==
167 HAMMER2_TRANS_ISFLUSH) {
172 while ((above = chain->above) != NULL) {
173 spin_lock(&above->cst.spin);
175 if (above->update_hi < trans->sync_tid)
176 above->update_hi = trans->sync_tid;
177 chain = TAILQ_LAST(&above->ownerq, h2_core_list);
179 TAILQ_FOREACH_REVERSE(chain, &above->ownerq,
180 h2_core_list, core_entry) {
181 if (trans->sync_tid >= chain->modify_tid &&
182 trans->sync_tid <= chain->delete_tid) {
187 spin_unlock(&above->cst.spin);
192 * Allocate a new disconnected chain element representing the specified
193 * bref. chain->refs is set to 1 and the passed bref is copied to
194 * chain->bref. chain->bytes is derived from the bref.
196 * chain->core is NOT allocated and the media data and bp pointers are left
197 * NULL. The caller must call chain_core_alloc() to allocate or associate
198 * a core with the chain.
200 * NOTE: Returns a referenced but unlocked (because there is no core) chain.
203 hammer2_chain_alloc(hammer2_mount_t *hmp, hammer2_pfsmount_t *pmp,
204 hammer2_trans_t *trans, hammer2_blockref_t *bref)
206 hammer2_chain_t *chain;
207 u_int bytes = 1U << (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
210 * Construct the appropriate system structure.
213 case HAMMER2_BREF_TYPE_INODE:
214 case HAMMER2_BREF_TYPE_INDIRECT:
215 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
216 case HAMMER2_BREF_TYPE_DATA:
217 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
219 * Chain's are really only associated with the hmp but we
220 * maintain a pmp association for per-mount memory tracking
221 * purposes. The pmp can be NULL.
223 chain = kmalloc(sizeof(*chain), hmp->mchain, M_WAITOK | M_ZERO);
226 atomic_add_long(&pmp->inmem_chains, 1);
229 case HAMMER2_BREF_TYPE_VOLUME:
230 case HAMMER2_BREF_TYPE_FREEMAP:
232 panic("hammer2_chain_alloc volume type illegal for op");
235 panic("hammer2_chain_alloc: unrecognized blockref type: %d",
241 chain->bytes = bytes;
243 chain->flags = HAMMER2_CHAIN_ALLOCATED;
244 chain->delete_tid = HAMMER2_MAX_TID;
247 * Set modify_tid if a transaction is creating the chain. When
248 * loading a chain from backing store trans is passed as NULL and
249 * modify_tid is left set to 0.
252 chain->modify_tid = trans->sync_tid;
258 * Associate an existing core with the chain or allocate a new core.
260 * The core is not locked. No additional refs on the chain are made.
261 * (trans) must not be NULL if (core) is not NULL.
263 * When chains are delete-duplicated during flushes we insert nchain on
264 * the ownerq after ochain instead of at the end in order to give the
265 * drop code visibility in the correct order, otherwise drops can be missed.
268 hammer2_chain_core_alloc(hammer2_trans_t *trans,
269 hammer2_chain_t *nchain, hammer2_chain_t *ochain)
271 hammer2_chain_core_t *core;
273 KKASSERT(nchain->core == NULL);
275 if (ochain == NULL) {
277 * Fresh core under nchain (no multi-homing of ochain's
280 core = kmalloc(sizeof(*core), nchain->hmp->mchain,
282 TAILQ_INIT(&core->layerq);
283 TAILQ_INIT(&core->ownerq);
287 core->update_hi = trans->sync_tid;
289 core->update_hi = nchain->bref.mirror_tid;
291 ccms_cst_init(&core->cst, nchain);
292 TAILQ_INSERT_TAIL(&core->ownerq, nchain, core_entry);
295 * Propagate the PFSROOT flag which we set on all subdirs
296 * under the super-root.
298 atomic_set_int(&nchain->flags,
299 ochain->flags & HAMMER2_CHAIN_PFSROOT);
302 * Duplicating ochain -> nchain. Set the DUPLICATED flag on
303 * ochain if nchain is not a snapshot.
305 * It is possible for the DUPLICATED flag to already be
306 * set when called via a flush operation because flush
307 * operations may have to work on elements with delete_tid's
308 * beyond the flush sync_tid. In this situation we must
309 * ensure that nchain is placed just after ochain in the
310 * ownerq and that the DUPLICATED flag is set on nchain so
311 * 'live' operations skip past it to the correct chain.
313 * The flusher understands the blockref synchronization state
314 * for any stale chains by observing bref.mirror_tid, which
315 * delete-duplicate replicates.
317 * WARNING! However, the case is disallowed when the flusher
318 * is allocating freemap space because this entails
319 * more than just adjusting a block table.
321 if (ochain->flags & HAMMER2_CHAIN_DUPLICATED) {
322 KKASSERT((trans->flags &
323 (HAMMER2_TRANS_ISFLUSH |
324 HAMMER2_TRANS_ISALLOCATING)) ==
325 HAMMER2_TRANS_ISFLUSH);
326 atomic_set_int(&nchain->flags,
327 HAMMER2_CHAIN_DUPLICATED);
329 if ((nchain->flags & HAMMER2_CHAIN_SNAPSHOT) == 0) {
330 atomic_set_int(&ochain->flags,
331 HAMMER2_CHAIN_DUPLICATED);
334 atomic_add_int(&core->sharecnt, 1);
336 spin_lock(&core->cst.spin);
340 if (core->update_hi < trans->sync_tid)
341 core->update_hi = trans->sync_tid;
345 * Maintain ordering for refactor test so we don't skip over
346 * a snapshot. Also, during flushes, delete-duplications
347 * for block-table updates can occur on blocks already
348 * deleted (delete-duplicated by a later transaction). We
349 * must insert nchain after ochain but before the later
350 * transaction's copy.
352 TAILQ_INSERT_AFTER(&core->ownerq, ochain, nchain, core_entry);
354 spin_unlock(&core->cst.spin);
359 * Add a reference to a chain element, preventing its destruction.
362 hammer2_chain_ref(hammer2_chain_t *chain)
364 atomic_add_int(&chain->refs, 1);
368 * Insert the chain in the core rbtree at the first layer
369 * which accepts it (for now we don't sort layers by the transaction tid)
371 #define HAMMER2_CHAIN_INSERT_SPIN 0x0001
372 #define HAMMER2_CHAIN_INSERT_LIVE 0x0002
373 #define HAMMER2_CHAIN_INSERT_RACE 0x0004
377 hammer2_chain_insert(hammer2_chain_core_t *above, hammer2_chain_layer_t *layer,
378 hammer2_chain_t *chain, int flags)
380 hammer2_chain_t *xchain;
381 hammer2_chain_layer_t *nlayer;
383 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
384 spin_lock(&above->cst.spin);
385 chain->above = above;
388 * Special case, place chain in a more recent layer than the specified
392 nlayer = TAILQ_PREV(layer, h2_layer_list, entry);
393 if (nlayer && RB_INSERT(hammer2_chain_tree,
394 &nlayer->rbtree, chain) == NULL) {
399 spin_unlock(&above->cst.spin);
400 KKASSERT((flags & HAMMER2_CHAIN_INSERT_LIVE) == 0);
401 nlayer = kmalloc(sizeof(*nlayer), chain->hmp->mchain,
403 RB_INIT(&nlayer->rbtree);
404 nlayer->good = 0xABCD;
405 spin_lock(&above->cst.spin);
407 TAILQ_INSERT_BEFORE(layer, nlayer, entry);
408 RB_INSERT(hammer2_chain_tree, &nlayer->rbtree, chain);
413 layer = TAILQ_FIRST(&above->layerq);
420 (xchain = RB_INSERT(hammer2_chain_tree,
421 &layer->rbtree, chain)) != NULL) {
423 * Either no layers have been allocated or the insertion
424 * failed. This is fatal if the conflicted xchain is not
425 * flagged as deleted. Caller may or may allow the failure.
427 if ((flags & HAMMER2_CHAIN_INSERT_RACE) &&
428 xchain && (xchain->flags & HAMMER2_CHAIN_DELETED) == 0) {
430 chain->inlayer = NULL;
431 kprintf("insertion race against %p\n", xchain);
436 * Allocate a new layer to resolve the issue.
438 spin_unlock(&above->cst.spin);
439 layer = kmalloc(sizeof(*layer), chain->hmp->mchain,
441 RB_INIT(&layer->rbtree);
442 layer->good = 0xABCD;
443 spin_lock(&above->cst.spin);
444 TAILQ_INSERT_HEAD(&above->layerq, layer, entry);
445 RB_INSERT(hammer2_chain_tree, &layer->rbtree, chain);
448 chain->inlayer = layer;
449 ++above->chain_count;
452 if ((flags & HAMMER2_CHAIN_INSERT_LIVE) &&
453 (chain->flags & HAMMER2_CHAIN_DELETED) == 0) {
454 atomic_add_int(&above->live_count, 1);
456 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
458 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
459 spin_unlock(&above->cst.spin);
463 * Drop the caller's reference to the chain. When the ref count drops to
464 * zero this function will disassociate the chain from its parent and
465 * deallocate it, then recursely drop the parent using the implied ref
466 * from the chain's chain->parent.
468 * WARNING! Just because we are able to deallocate a chain doesn't mean
469 * that chain->core->rbtree is empty. There can still be a sharecnt
470 * on chain->core and RBTREE entries that refer to different parents.
472 static hammer2_chain_t *hammer2_chain_lastdrop(hammer2_chain_t *chain,
473 struct h2_core_list *delayq);
476 hammer2_chain_drop(hammer2_chain_t *chain)
478 struct h2_core_list delayq;
479 hammer2_chain_t *scan;
483 if (hammer2_debug & 0x200000)
486 if (chain->flags & HAMMER2_CHAIN_MOVED)
488 if (chain->flags & HAMMER2_CHAIN_MODIFIED)
490 KKASSERT(chain->refs > need);
500 chain = hammer2_chain_lastdrop(chain, &delayq);
502 if (atomic_cmpset_int(&chain->refs, refs, refs - 1))
504 /* retry the same chain */
508 * When we've exhausted lastdrop chaining pull off of delayq.
509 * chains on delayq are dead but are used to placehold other
510 * chains which we added a ref to for the purpose of dropping.
513 hammer2_mount_t *hmp;
515 if ((scan = TAILQ_FIRST(&delayq)) != NULL) {
516 chain = (void *)scan->data;
517 TAILQ_REMOVE(&delayq, scan, core_entry);
518 scan->flags &= ~HAMMER2_CHAIN_ALLOCATED;
521 kfree(scan, hmp->mchain);
528 * Safe handling of the 1->0 transition on chain. Returns a chain for
529 * recursive drop or NULL, possibly returning the same chain if the atomic
532 * Whem two chains need to be recursively dropped we use the chain
533 * we would otherwise free to placehold the additional chain. It's a bit
534 * convoluted but we can't just recurse without potentially blowing out
537 * The cst spinlock is allowed nest child-to-parent (not parent-to-child).
541 hammer2_chain_lastdrop(hammer2_chain_t *chain, struct h2_core_list *delayq)
543 hammer2_pfsmount_t *pmp;
544 hammer2_mount_t *hmp;
545 hammer2_chain_core_t *above;
546 hammer2_chain_core_t *core;
547 hammer2_chain_layer_t *layer;
548 hammer2_chain_t *rdrop1;
549 hammer2_chain_t *rdrop2;
552 * Spinlock the core and check to see if it is empty. If it is
553 * not empty we leave chain intact with refs == 0. The elements
554 * in core->rbtree are associated with other chains contemporary
555 * with ours but not with our chain directly.
557 if ((core = chain->core) != NULL) {
558 spin_lock(&core->cst.spin);
561 * We can't free chains with children because there might
562 * be a flush dependency.
564 * NOTE: We return (chain) on failure to retry.
566 if (core->chain_count) {
567 if (atomic_cmpset_int(&chain->refs, 1, 0))
568 chain = NULL; /* success */
569 spin_unlock(&core->cst.spin);
572 /* no chains left under us */
575 * Because various parts of the code, including the inode
576 * structure, might be holding a stale chain and need to
577 * iterate to a non-stale sibling, we cannot remove siblings
578 * unless they are at the head of chain.
580 * We can't free a live chain unless it is a the head
581 * of its ownerq. If we were to then the go-to chain
582 * would revert to the prior deleted chain.
584 if (TAILQ_FIRST(&core->ownerq) != chain) {
585 if (atomic_cmpset_int(&chain->refs, 1, 0))
586 chain = NULL; /* success */
587 spin_unlock(&core->cst.spin);
593 * chain->core has no children left so no accessors can get to our
594 * chain from there. Now we have to lock the above core to interlock
595 * remaining possible accessors that might bump chain's refs before
596 * we can safely drop chain's refs with intent to free the chain.
599 pmp = chain->pmp; /* can be NULL */
605 * Spinlock the parent and try to drop the last ref on chain.
606 * On success remove chain from its parent, otherwise return NULL.
608 * (normal core locks are top-down recursive but we define core
609 * spinlocks as bottom-up recursive, so this is safe).
611 if ((above = chain->above) != NULL) {
612 spin_lock(&above->cst.spin);
613 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) {
614 /* 1->0 transition failed */
615 spin_unlock(&above->cst.spin);
617 spin_unlock(&core->cst.spin);
618 return(chain); /* retry */
622 * 1->0 transition successful, remove chain from its
623 * above core. Track layer for removal/freeing.
625 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
626 layer = chain->inlayer;
627 RB_REMOVE(hammer2_chain_tree, &layer->rbtree, chain);
628 --above->chain_count;
629 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
631 chain->inlayer = NULL;
633 if (RB_EMPTY(&layer->rbtree) && layer->refs == 0) {
634 TAILQ_REMOVE(&above->layerq, layer, entry);
640 * If our chain was the last chain in the parent's core the
641 * core is now empty and its parents might now be droppable.
642 * Try to drop the first multi-homed parent by gaining a
643 * ref on it here and then dropping it below.
645 if (above->chain_count == 0) {
646 rdrop1 = TAILQ_FIRST(&above->ownerq);
648 atomic_cmpset_int(&rdrop1->refs, 0, 1) == 0) {
652 spin_unlock(&above->cst.spin);
653 above = NULL; /* safety */
657 * Successful 1->0 transition and the chain can be destroyed now.
659 * We still have the core spinlock (if core is non-NULL), and core's
660 * chain_count is 0. The above spinlock is gone.
662 * Remove chain from ownerq. Once core has no more owners (and no
663 * children which is already the case) we can destroy core.
665 * If core has more owners we may be able to continue a bottom-up
666 * drop with our next sibling.
671 TAILQ_REMOVE(&core->ownerq, chain, core_entry);
672 rdrop2 = TAILQ_FIRST(&core->ownerq);
673 if (rdrop2 && atomic_cmpset_int(&rdrop2->refs, 0, 1) == 0)
675 spin_unlock(&core->cst.spin);
678 * We can do the final 1->0 transition with an atomic op
679 * after releasing core's spinlock.
681 if (atomic_fetchadd_int(&core->sharecnt, -1) == 1) {
683 * On the 1->0 transition of core we can destroy
684 * it. Any remaining layers should no longer be
685 * referenced or visibile to other threads.
687 KKASSERT(TAILQ_EMPTY(&core->ownerq));
689 layer->good = 0xEF00;
690 kfree(layer, hmp->mchain);
692 while ((layer = TAILQ_FIRST(&core->layerq)) != NULL) {
693 KKASSERT(layer->refs == 0 &&
694 RB_EMPTY(&layer->rbtree));
695 TAILQ_REMOVE(&core->layerq, layer, entry);
696 layer->good = 0xEF01;
697 kfree(layer, hmp->mchain);
700 KKASSERT(core->cst.count == 0);
701 KKASSERT(core->cst.upgrade == 0);
703 kfree(core, hmp->mchain);
705 core = NULL; /* safety */
709 * All spin locks are gone, finish freeing stuff.
711 KKASSERT((chain->flags & (HAMMER2_CHAIN_MOVED |
712 HAMMER2_CHAIN_MODIFIED)) == 0);
713 hammer2_chain_drop_data(chain, 1);
715 KKASSERT(chain->dio == NULL);
718 * Free saved empty layer and return chained drop.
721 layer->good = 0xEF02;
722 kfree(layer, hmp->mchain);
726 * Once chain resources are gone we can use the now dead chain
727 * structure to placehold what might otherwise require a recursive
728 * drop, because we have potentially two things to drop and can only
729 * return one directly.
731 if (rdrop1 && rdrop2) {
732 KKASSERT(chain->flags & HAMMER2_CHAIN_ALLOCATED);
733 chain->data = (void *)rdrop1;
734 TAILQ_INSERT_TAIL(delayq, chain, core_entry);
736 } else if (chain->flags & HAMMER2_CHAIN_ALLOCATED) {
737 chain->flags &= ~HAMMER2_CHAIN_ALLOCATED;
739 kfree(chain, hmp->mchain);
742 atomic_add_long(&pmp->inmem_chains, -1);
743 hammer2_chain_memory_wakeup(pmp);
747 * Either or both can be NULL. We already handled the case where
748 * both might not have been NULL.
757 * On either last lock release or last drop
760 hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop)
762 hammer2_mount_t *hmp = chain->hmp;
764 switch(chain->bref.type) {
765 case HAMMER2_BREF_TYPE_VOLUME:
766 case HAMMER2_BREF_TYPE_FREEMAP:
770 case HAMMER2_BREF_TYPE_INODE:
772 kfree(chain->data, hmp->mchain);
776 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
778 kfree(chain->data, hmp->mchain);
783 KKASSERT(chain->data == NULL);
789 * Ref and lock a chain element, acquiring its data with I/O if necessary,
790 * and specify how you would like the data to be resolved.
792 * Returns 0 on success or an error code if the data could not be acquired.
793 * The chain element is locked on return regardless of whether an error
796 * The lock is allowed to recurse, multiple locking ops will aggregate
797 * the requested resolve types. Once data is assigned it will not be
798 * removed until the last unlock.
800 * HAMMER2_RESOLVE_NEVER - Do not resolve the data element.
801 * (typically used to avoid device/logical buffer
804 * HAMMER2_RESOLVE_MAYBE - Do not resolve data elements for chains in
805 * the INITIAL-create state (indirect blocks only).
807 * Do not resolve data elements for DATA chains.
808 * (typically used to avoid device/logical buffer
811 * HAMMER2_RESOLVE_ALWAYS- Always resolve the data element.
813 * HAMMER2_RESOLVE_SHARED- (flag) The chain is locked shared, otherwise
814 * it will be locked exclusive.
816 * NOTE: Embedded elements (volume header, inodes) are always resolved
819 * NOTE: Specifying HAMMER2_RESOLVE_ALWAYS on a newly-created non-embedded
820 * element will instantiate and zero its buffer, and flush it on
823 * NOTE: (data) elements are normally locked RESOLVE_NEVER or RESOLVE_MAYBE
824 * so as not to instantiate a device buffer, which could alias against
825 * a logical file buffer. However, if ALWAYS is specified the
826 * device buffer will be instantiated anyway.
828 * WARNING! If data must be fetched a shared lock will temporarily be
829 * upgraded to exclusive. However, a deadlock can occur if
830 * the caller owns more than one shared lock.
833 hammer2_chain_lock(hammer2_chain_t *chain, int how)
835 hammer2_mount_t *hmp;
836 hammer2_chain_core_t *core;
837 hammer2_blockref_t *bref;
843 * Ref and lock the element. Recursive locks are allowed.
845 if ((how & HAMMER2_RESOLVE_NOREF) == 0)
846 hammer2_chain_ref(chain);
847 atomic_add_int(&chain->lockcnt, 1);
850 KKASSERT(hmp != NULL);
853 * Get the appropriate lock.
856 if (how & HAMMER2_RESOLVE_SHARED)
857 ccms_thread_lock(&core->cst, CCMS_STATE_SHARED);
859 ccms_thread_lock(&core->cst, CCMS_STATE_EXCLUSIVE);
862 * If we already have a valid data pointer no further action is
869 * Do we have to resolve the data?
871 switch(how & HAMMER2_RESOLVE_MASK) {
872 case HAMMER2_RESOLVE_NEVER:
874 case HAMMER2_RESOLVE_MAYBE:
875 if (chain->flags & HAMMER2_CHAIN_INITIAL)
877 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA)
880 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE)
883 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF)
886 case HAMMER2_RESOLVE_ALWAYS:
891 * Upgrade to an exclusive lock so we can safely manipulate the
892 * buffer cache. If another thread got to it before us we
895 ostate = ccms_thread_lock_upgrade(&core->cst);
897 ccms_thread_lock_downgrade(&core->cst, ostate);
902 * We must resolve to a device buffer, either by issuing I/O or
903 * by creating a zero-fill element. We do not mark the buffer
904 * dirty when creating a zero-fill element (the hammer2_chain_modify()
905 * API must still be used to do that).
907 * The device buffer is variable-sized in powers of 2 down
908 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
909 * chunk always contains buffers of the same size. (XXX)
911 * The minimum physical IO size may be larger than the variable
917 * The getblk() optimization can only be used on newly created
918 * elements if the physical block size matches the request.
920 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
921 error = hammer2_io_new(hmp, bref->data_off, chain->bytes,
924 error = hammer2_io_bread(hmp, bref->data_off, chain->bytes,
926 adjreadcounter(&chain->bref, chain->bytes);
930 kprintf("hammer2_chain_lock: I/O error %016jx: %d\n",
931 (intmax_t)bref->data_off, error);
932 hammer2_io_bqrelse(&chain->dio);
933 ccms_thread_lock_downgrade(&core->cst, ostate);
938 * We can clear the INITIAL state now, we've resolved the buffer
939 * to zeros and marked it dirty with hammer2_io_new().
941 bdata = hammer2_io_data(chain->dio, chain->bref.data_off);
942 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
943 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
947 * Setup the data pointer, either pointing it to an embedded data
948 * structure and copying the data from the buffer, or pointing it
951 * The buffer is not retained when copying to an embedded data
952 * structure in order to avoid potential deadlocks or recursions
953 * on the same physical buffer.
955 switch (bref->type) {
956 case HAMMER2_BREF_TYPE_VOLUME:
957 case HAMMER2_BREF_TYPE_FREEMAP:
959 * Copy data from bp to embedded buffer
961 panic("hammer2_chain_lock: called on unresolved volume header");
963 case HAMMER2_BREF_TYPE_INODE:
965 * Copy data from dio to embedded buffer, do not retain the
968 KKASSERT(chain->bytes == sizeof(chain->data->ipdata));
969 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
970 chain->data = kmalloc(sizeof(chain->data->ipdata),
971 hmp->mchain, M_WAITOK | M_ZERO);
972 bcopy(bdata, &chain->data->ipdata, chain->bytes);
973 hammer2_io_bqrelse(&chain->dio);
975 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
976 KKASSERT(chain->bytes == sizeof(chain->data->bmdata));
977 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
978 chain->data = kmalloc(sizeof(chain->data->bmdata),
979 hmp->mchain, M_WAITOK | M_ZERO);
980 bcopy(bdata, &chain->data->bmdata, chain->bytes);
981 hammer2_io_bqrelse(&chain->dio);
983 case HAMMER2_BREF_TYPE_INDIRECT:
984 case HAMMER2_BREF_TYPE_DATA:
985 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
988 * Point data at the device buffer and leave bp intact.
990 chain->data = (void *)bdata;
993 ccms_thread_lock_downgrade(&core->cst, ostate);
998 * This basically calls hammer2_io_breadcb() but does some pre-processing
999 * of the chain first to handle certain cases.
1002 hammer2_chain_load_async(hammer2_chain_t *chain,
1003 void (*callback)(hammer2_io_t *dio,
1004 hammer2_chain_t *chain,
1005 void *arg_p, off_t arg_o),
1006 void *arg_p, off_t arg_o)
1008 hammer2_mount_t *hmp;
1009 struct hammer2_io *dio;
1010 hammer2_blockref_t *bref;
1014 callback(NULL, chain, arg_p, arg_o);
1019 * We must resolve to a device buffer, either by issuing I/O or
1020 * by creating a zero-fill element. We do not mark the buffer
1021 * dirty when creating a zero-fill element (the hammer2_chain_modify()
1022 * API must still be used to do that).
1024 * The device buffer is variable-sized in powers of 2 down
1025 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
1026 * chunk always contains buffers of the same size. (XXX)
1028 * The minimum physical IO size may be larger than the variable
1031 bref = &chain->bref;
1035 * The getblk() optimization can only be used on newly created
1036 * elements if the physical block size matches the request.
1038 if ((chain->flags & HAMMER2_CHAIN_INITIAL) &&
1039 chain->bytes == hammer2_devblksize(chain->bytes)) {
1040 error = hammer2_io_new(hmp, bref->data_off, chain->bytes, &dio);
1041 KKASSERT(error == 0);
1042 callback(dio, chain, arg_p, arg_o);
1047 * Otherwise issue a read
1049 adjreadcounter(&chain->bref, chain->bytes);
1050 hammer2_io_breadcb(hmp, bref->data_off, chain->bytes,
1051 callback, chain, arg_p, arg_o);
1055 * Unlock and deref a chain element.
1057 * On the last lock release any non-embedded data (chain->dio) will be
1061 hammer2_chain_unlock(hammer2_chain_t *chain)
1063 hammer2_chain_core_t *core = chain->core;
1064 ccms_state_t ostate;
1069 * The core->cst lock can be shared across several chains so we
1070 * need to track the per-chain lockcnt separately.
1072 * If multiple locks are present (or being attempted) on this
1073 * particular chain we can just unlock, drop refs, and return.
1075 * Otherwise fall-through on the 1->0 transition.
1078 lockcnt = chain->lockcnt;
1079 KKASSERT(lockcnt > 0);
1082 if (atomic_cmpset_int(&chain->lockcnt,
1083 lockcnt, lockcnt - 1)) {
1084 ccms_thread_unlock(&core->cst);
1085 hammer2_chain_drop(chain);
1089 if (atomic_cmpset_int(&chain->lockcnt, 1, 0))
1096 * On the 1->0 transition we upgrade the core lock (if necessary)
1097 * to exclusive for terminal processing. If after upgrading we find
1098 * that lockcnt is non-zero, another thread is racing us and will
1099 * handle the unload for us later on, so just cleanup and return
1100 * leaving the data/io intact
1102 * Otherwise if lockcnt is still 0 it is possible for it to become
1103 * non-zero and race, but since we hold the core->cst lock
1104 * exclusively all that will happen is that the chain will be
1105 * reloaded after we unload it.
1107 ostate = ccms_thread_lock_upgrade(&core->cst);
1108 if (chain->lockcnt) {
1109 ccms_thread_unlock_upgraded(&core->cst, ostate);
1110 hammer2_chain_drop(chain);
1115 * Shortcut the case if the data is embedded or not resolved.
1117 * Do NOT NULL out chain->data (e.g. inode data), it might be
1120 if (chain->dio == NULL) {
1121 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0)
1122 hammer2_chain_drop_data(chain, 0);
1123 ccms_thread_unlock_upgraded(&core->cst, ostate);
1124 hammer2_chain_drop(chain);
1131 if (hammer2_io_isdirty(chain->dio) == 0) {
1133 } else if (chain->flags & HAMMER2_CHAIN_IOFLUSH) {
1134 switch(chain->bref.type) {
1135 case HAMMER2_BREF_TYPE_DATA:
1136 counterp = &hammer2_ioa_file_write;
1138 case HAMMER2_BREF_TYPE_INODE:
1139 counterp = &hammer2_ioa_meta_write;
1141 case HAMMER2_BREF_TYPE_INDIRECT:
1142 counterp = &hammer2_ioa_indr_write;
1144 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1145 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1146 counterp = &hammer2_ioa_fmap_write;
1149 counterp = &hammer2_ioa_volu_write;
1152 *counterp += chain->bytes;
1154 switch(chain->bref.type) {
1155 case HAMMER2_BREF_TYPE_DATA:
1156 counterp = &hammer2_iod_file_write;
1158 case HAMMER2_BREF_TYPE_INODE:
1159 counterp = &hammer2_iod_meta_write;
1161 case HAMMER2_BREF_TYPE_INDIRECT:
1162 counterp = &hammer2_iod_indr_write;
1164 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1165 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1166 counterp = &hammer2_iod_fmap_write;
1169 counterp = &hammer2_iod_volu_write;
1172 *counterp += chain->bytes;
1176 * Clean out the dio.
1178 * If a device buffer was used for data be sure to destroy the
1179 * buffer when we are done to avoid aliases (XXX what about the
1180 * underlying VM pages?).
1182 * NOTE: Freemap leaf's use reserved blocks and thus no aliasing
1185 * NOTE: The isdirty check tracks whether we have to bdwrite() the
1186 * buffer or not. The buffer might already be dirty. The
1187 * flag is re-set when chain_modify() is called, even if
1188 * MODIFIED is already set, allowing the OS to retire the
1189 * buffer independent of a hammer2 flush.
1192 if ((chain->flags & HAMMER2_CHAIN_IOFLUSH) &&
1193 hammer2_io_isdirty(chain->dio)) {
1194 hammer2_io_bawrite(&chain->dio);
1196 hammer2_io_bqrelse(&chain->dio);
1198 ccms_thread_unlock_upgraded(&core->cst, ostate);
1199 hammer2_chain_drop(chain);
1203 * This counts the number of live blockrefs in a block array and
1204 * also calculates the point at which all remaining blockrefs are empty.
1205 * This routine can only be called on a live chain (DUPLICATED flag not set).
1207 * NOTE: Flag is not set until after the count is complete, allowing
1208 * callers to test the flag without holding the spinlock.
1210 * NOTE: If base is NULL the related chain is still in the INITIAL
1211 * state and there are no blockrefs to count.
1213 * NOTE: live_count may already have some counts accumulated due to
1214 * creation and deletion and could even be initially negative.
1217 hammer2_chain_countbrefs(hammer2_chain_t *chain,
1218 hammer2_blockref_t *base, int count)
1220 hammer2_chain_core_t *core = chain->core;
1222 KKASSERT((chain->flags & HAMMER2_CHAIN_DUPLICATED) == 0);
1224 spin_lock(&core->cst.spin);
1225 if ((core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0) {
1227 while (--count >= 0) {
1228 if (base[count].type)
1231 core->live_zero = count + 1;
1232 while (count >= 0) {
1233 if (base[count].type)
1234 atomic_add_int(&core->live_count, 1);
1238 core->live_zero = 0;
1240 /* else do not modify live_count */
1241 atomic_set_int(&core->flags, HAMMER2_CORE_COUNTEDBREFS);
1243 spin_unlock(&core->cst.spin);
1247 * Resize the chain's physical storage allocation in-place. This may
1248 * replace the passed-in chain with a new chain.
1250 * Chains can be resized smaller without reallocating the storage.
1251 * Resizing larger will reallocate the storage.
1253 * Must be passed an exclusively locked parent and chain, returns a new
1254 * exclusively locked chain at the same index and unlocks the old chain.
1255 * Flushes the buffer if necessary.
1257 * This function is mostly used with DATA blocks locked RESOLVE_NEVER in order
1258 * to avoid instantiating a device buffer that conflicts with the vnode
1259 * data buffer. That is, the passed-in bp is a logical buffer, whereas
1260 * any chain-oriented bp would be a device buffer.
1262 * XXX return error if cannot resize.
1265 hammer2_chain_resize(hammer2_trans_t *trans, hammer2_inode_t *ip,
1266 hammer2_chain_t *parent, hammer2_chain_t **chainp,
1267 int nradix, int flags)
1269 hammer2_mount_t *hmp;
1270 hammer2_chain_t *chain;
1278 * Only data and indirect blocks can be resized for now.
1279 * (The volu root, inodes, and freemap elements use a fixed size).
1281 KKASSERT(chain != &hmp->vchain);
1282 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA ||
1283 chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT);
1286 * Nothing to do if the element is already the proper size
1288 obytes = chain->bytes;
1289 nbytes = 1U << nradix;
1290 if (obytes == nbytes)
1294 * Delete the old chain and duplicate it at the same (parent, index),
1295 * returning a new chain. This allows the old chain to still be
1296 * used by the flush code. The new chain will be returned in a
1299 * The parent does not have to be locked for the delete/duplicate call,
1300 * but is in this particular code path.
1302 * NOTE: If we are not crossing a synchronization point the
1303 * duplication code will simply reuse the existing chain
1306 hammer2_chain_delete_duplicate(trans, &chain, 0);
1309 * Relocate the block, even if making it smaller (because different
1310 * block sizes may be in different regions).
1312 hammer2_freemap_alloc(trans, chain->hmp, &chain->bref, nbytes);
1313 chain->bytes = nbytes;
1314 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
1315 /*ip->delta_dcount += (ssize_t)(nbytes - obytes);*/ /* XXX atomic */
1318 * For now just support it on DATA chains (and not on indirect
1321 KKASSERT(chain->dio == NULL);
1325 * Make sure the chain is marked MOVED and propagate the update
1326 * to the root for flush.
1328 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
1329 hammer2_chain_ref(chain);
1330 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
1332 hammer2_chain_setsubmod(trans, chain);
1338 * Set a chain modified, making it read-write and duplicating it if necessary.
1339 * This function will assign a new physical block to the chain if necessary
1341 * Duplication of already-modified chains is possible when the modification
1342 * crosses a flush synchronization boundary.
1344 * Non-data blocks - The chain should be locked to at least the RESOLVE_MAYBE
1345 * level or the COW operation will not work.
1347 * Data blocks - The chain is usually locked RESOLVE_NEVER so as not to
1348 * run the data through the device buffers.
1350 * This function may return a different chain than was passed, in which case
1351 * the old chain will be unlocked and the new chain will be locked.
1353 * ip->chain may be adjusted by hammer2_chain_modify_ip().
1355 hammer2_inode_data_t *
1356 hammer2_chain_modify_ip(hammer2_trans_t *trans, hammer2_inode_t *ip,
1357 hammer2_chain_t **chainp, int flags)
1359 atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
1360 hammer2_chain_modify(trans, chainp, flags);
1361 if (ip->chain != *chainp)
1362 hammer2_inode_repoint(ip, NULL, *chainp);
1364 vsetisdirty(ip->vp);
1365 return(&ip->chain->data->ipdata);
1369 hammer2_chain_modify(hammer2_trans_t *trans, hammer2_chain_t **chainp,
1372 hammer2_mount_t *hmp;
1373 hammer2_chain_t *chain;
1383 kprintf("MODIFY %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1386 * Data must be resolved if already assigned unless explicitly
1387 * flagged otherwise.
1389 if (chain->data == NULL && (flags & HAMMER2_MODIFY_OPTDATA) == 0 &&
1390 (chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX)) {
1391 hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
1392 hammer2_chain_unlock(chain);
1396 * data is not optional for freemap chains (we must always be sure
1397 * to copy the data on COW storage allocations).
1399 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
1400 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
1401 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) ||
1402 (flags & HAMMER2_MODIFY_OPTDATA) == 0);
1406 * Determine if a delete-duplicate is needed.
1408 * (a) Modify_tid is part of a prior flush
1409 * (b) Transaction is concurrent with a flush (has higher tid)
1410 * (c) and chain is not in the initial state (freshly created)
1411 * (d) and caller didn't request an in-place modification.
1413 * The freemap and volume header special chains are never D-Dd.
1415 if (chain->modify_tid != trans->sync_tid && /* cross boundary */
1416 (flags & HAMMER2_MODIFY_INPLACE) == 0) { /* from d-d */
1417 if (chain != &hmp->fchain && chain != &hmp->vchain) {
1418 KKASSERT((flags & HAMMER2_MODIFY_ASSERTNOCOPY) == 0);
1419 hammer2_chain_delete_duplicate(trans, chainp, 0);
1421 kprintf("RET1A %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1425 kprintf("RET1B %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1431 * Fall through if fchain or vchain, clearing the CHAIN_FLUSHED
1432 * flag. Basically other chains are delete-duplicated and so
1433 * the duplicated chains of course will not have the FLUSHED
1434 * flag set, but fchain and vchain are special-cased and the
1435 * flag must be cleared when changing modify_tid.
1437 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FLUSHED);
1441 * Otherwise do initial-chain handling
1443 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) {
1444 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
1445 hammer2_chain_ref(chain);
1449 * The modification or re-modification requires an allocation and
1452 * We normally always allocate new storage here. If storage exists
1453 * and MODIFY_NOREALLOC is passed in, we do not allocate new storage.
1455 if (chain != &hmp->vchain && chain != &hmp->fchain) {
1456 if ((chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX) == 0 ||
1457 ((flags & HAMMER2_MODIFY_NOREALLOC) == 0 &&
1458 chain->modify_tid != trans->sync_tid)
1460 hammer2_freemap_alloc(trans, chain->hmp,
1461 &chain->bref, chain->bytes);
1462 /* XXX failed allocation */
1463 } else if (chain->flags & HAMMER2_CHAIN_FORCECOW) {
1464 hammer2_freemap_alloc(trans, chain->hmp,
1465 &chain->bref, chain->bytes);
1466 /* XXX failed allocation */
1468 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
1471 chain->modify_tid = trans->sync_tid;
1472 if ((flags & HAMMER2_MODIFY_NO_MODIFY_TID) == 0)
1473 chain->bref.modify_tid = trans->sync_tid;
1476 * Do not COW if OPTDATA is set. INITIAL flag remains unchanged.
1477 * (OPTDATA does not prevent [re]allocation of storage, only the
1478 * related copy-on-write op).
1480 if (flags & HAMMER2_MODIFY_OPTDATA)
1484 * Clearing the INITIAL flag (for indirect blocks) indicates that
1485 * we've processed the uninitialized storage allocation.
1487 * If this flag is already clear we are likely in a copy-on-write
1488 * situation but we have to be sure NOT to bzero the storage if
1489 * no data is present.
1491 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
1492 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1499 * Instantiate data buffer and possibly execute COW operation
1501 switch(chain->bref.type) {
1502 case HAMMER2_BREF_TYPE_VOLUME:
1503 case HAMMER2_BREF_TYPE_FREEMAP:
1504 case HAMMER2_BREF_TYPE_INODE:
1505 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1507 * The data is embedded, no copy-on-write operation is
1510 KKASSERT(chain->dio == NULL);
1512 case HAMMER2_BREF_TYPE_DATA:
1513 case HAMMER2_BREF_TYPE_INDIRECT:
1514 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1516 * Perform the copy-on-write operation
1518 KKASSERT(chain != &hmp->vchain && chain != &hmp->fchain);
1521 error = hammer2_io_new(hmp, chain->bref.data_off,
1522 chain->bytes, &dio);
1524 error = hammer2_io_bread(hmp, chain->bref.data_off,
1525 chain->bytes, &dio);
1527 adjreadcounter(&chain->bref, chain->bytes);
1528 KKASSERT(error == 0);
1530 bdata = hammer2_io_data(dio, chain->bref.data_off);
1533 * Copy or zero-fill on write depending on whether
1534 * chain->data exists or not and set the dirty state for
1535 * the new buffer. Retire the existing buffer.
1538 KKASSERT(chain->dio != NULL);
1539 if (chain->data != (void *)bdata) {
1540 bcopy(chain->data, bdata, chain->bytes);
1542 } else if (wasinitial == 0) {
1544 * We have a problem. We were asked to COW but
1545 * we don't have any data to COW with!
1547 panic("hammer2_chain_modify: having a COW %p\n",
1550 hammer2_io_brelse(&chain->dio);
1551 chain->data = (void *)bdata;
1553 hammer2_io_setdirty(dio); /* modified by bcopy above */
1556 panic("hammer2_chain_modify: illegal non-embedded type %d",
1563 kprintf("RET2 %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1565 hammer2_chain_setsubmod(trans, chain);
1569 * Mark the volume as having been modified. This short-cut version
1570 * does not have to lock the volume's chain, which allows the ioctl
1571 * code to make adjustments to connections without deadlocking. XXX
1573 * No ref is made on vchain when flagging it MODIFIED.
1576 hammer2_modify_volume(hammer2_mount_t *hmp)
1578 hammer2_voldata_lock(hmp);
1579 hammer2_voldata_unlock(hmp, 1);
1583 * This function returns the chain at the nearest key within the specified
1584 * range with the highest delete_tid. The core spinlock must be held on
1585 * call and the returned chain will be referenced but not locked.
1587 * The returned chain may or may not be in a deleted state. Note that
1588 * live chains have a delete_tid = MAX_TID.
1590 * This function will recurse through chain->rbtree as necessary and will
1591 * return a *key_nextp suitable for iteration. *key_nextp is only set if
1592 * the iteration value is less than the current value of *key_nextp.
1594 * The caller should use (*key_nextp) to calculate the actual range of
1595 * the returned element, which will be (key_beg to *key_nextp - 1), because
1596 * there might be another element which is superior to the returned element
1599 * (*key_nextp) can be passed as key_beg in an iteration only while non-NULL
1600 * chains continue to be returned. On EOF (*key_nextp) may overflow since
1601 * it will wind up being (key_end + 1).
1603 struct hammer2_chain_find_info {
1604 hammer2_chain_t *best;
1605 hammer2_key_t key_beg;
1606 hammer2_key_t key_end;
1607 hammer2_key_t key_next;
1610 static int hammer2_chain_find_cmp(hammer2_chain_t *child, void *data);
1611 static int hammer2_chain_find_callback(hammer2_chain_t *child, void *data);
1615 hammer2_chain_find(hammer2_chain_t *parent, hammer2_key_t *key_nextp,
1616 hammer2_key_t key_beg, hammer2_key_t key_end)
1618 struct hammer2_chain_find_info info;
1619 hammer2_chain_layer_t *layer;
1622 info.key_beg = key_beg;
1623 info.key_end = key_end;
1624 info.key_next = *key_nextp;
1626 KKASSERT(parent->core->good == 0x1234);
1627 TAILQ_FOREACH(layer, &parent->core->layerq, entry) {
1628 KKASSERT(layer->good == 0xABCD);
1629 RB_SCAN(hammer2_chain_tree, &layer->rbtree,
1630 hammer2_chain_find_cmp, hammer2_chain_find_callback,
1633 *key_nextp = info.key_next;
1635 kprintf("chain_find %p %016jx:%016jx next=%016jx\n",
1636 parent, key_beg, key_end, *key_nextp);
1644 hammer2_chain_find_cmp(hammer2_chain_t *child, void *data)
1646 struct hammer2_chain_find_info *info = data;
1647 hammer2_key_t child_beg;
1648 hammer2_key_t child_end;
1650 child_beg = child->bref.key;
1651 child_end = child_beg + ((hammer2_key_t)1 << child->bref.keybits) - 1;
1653 if (child_end < info->key_beg)
1655 if (child_beg > info->key_end)
1662 hammer2_chain_find_callback(hammer2_chain_t *child, void *data)
1664 struct hammer2_chain_find_info *info = data;
1665 hammer2_chain_t *best;
1666 hammer2_key_t child_end;
1670 * Skip deleted chains which have been flushed (MOVED no longer set),
1671 * causes caller to check blockref array.
1673 if ((child->flags & (HAMMER2_CHAIN_DELETED | HAMMER2_CHAIN_MOVED)) ==
1674 HAMMER2_CHAIN_DELETED) {
1683 if ((best = info->best) == NULL) {
1685 * No previous best. Assign best
1688 } else if (best->bref.key <= info->key_beg &&
1689 child->bref.key <= info->key_beg) {
1691 * If our current best is flush with key_beg and child is
1692 * also flush with key_beg choose based on delete_tid.
1694 * key_next will automatically be limited to the smaller of
1695 * the two end-points.
1697 if (child->delete_tid > best->delete_tid)
1699 } else if (child->bref.key < best->bref.key) {
1701 * Child has a nearer key and best is not flush with key_beg.
1702 * Truncate key_next to the old best key iff it had a better
1706 if (best->delete_tid >= child->delete_tid &&
1707 (info->key_next > best->bref.key || info->key_next == 0))
1708 info->key_next = best->bref.key;
1709 } else if (child->bref.key == best->bref.key) {
1711 * If our current best is flush with the child then choose
1712 * based on delete_tid.
1714 * key_next will automatically be limited to the smaller of
1715 * the two end-points.
1717 if (child->delete_tid > best->delete_tid)
1721 * Keep the current best but truncate key_next to the child's
1722 * base iff the child has a higher delete_tid.
1724 * key_next will also automatically be limited to the smaller
1725 * of the two end-points (probably not necessary for this case
1726 * but we do it anyway).
1728 if (child->delete_tid >= best->delete_tid &&
1729 (info->key_next > child->bref.key || info->key_next == 0))
1730 info->key_next = child->bref.key;
1734 * Always truncate key_next based on child's end-of-range.
1736 child_end = child->bref.key + ((hammer2_key_t)1 << child->bref.keybits);
1737 if (child_end && (info->key_next > child_end || info->key_next == 0))
1738 info->key_next = child_end;
1744 * Retrieve the specified chain from a media blockref, creating the
1745 * in-memory chain structure which reflects it. modify_tid will be
1746 * left 0 which forces any modifications to issue a delete-duplicate.
1748 * NULL is returned if the insertion races.
1750 * Caller must hold the parent locked shared or exclusive since we may
1751 * need the parent's bref array to find our block.
1754 hammer2_chain_get(hammer2_chain_t *parent, hammer2_blockref_t *bref)
1756 hammer2_mount_t *hmp = parent->hmp;
1757 hammer2_chain_core_t *above = parent->core;
1758 hammer2_chain_t *chain;
1761 * Allocate a chain structure representing the existing media
1762 * entry. Resulting chain has one ref and is not locked.
1764 chain = hammer2_chain_alloc(hmp, parent->pmp, NULL, bref);
1765 hammer2_chain_core_alloc(NULL, chain, NULL);
1766 /* ref'd chain returned */
1767 chain->modify_tid = chain->bref.mirror_tid;
1770 * Link the chain into its parent. A spinlock is required to safely
1771 * access the RBTREE, and it is possible to collide with another
1772 * hammer2_chain_get() operation because the caller might only hold
1773 * a shared lock on the parent.
1775 KKASSERT(parent->refs > 0);
1776 hammer2_chain_insert(above, NULL, chain,
1777 HAMMER2_CHAIN_INSERT_SPIN |
1778 HAMMER2_CHAIN_INSERT_RACE);
1779 if ((chain->flags & HAMMER2_CHAIN_ONRBTREE) == 0) {
1780 kprintf("chain %p not on RBTREE\n", chain);
1781 hammer2_chain_drop(chain);
1786 * Return our new chain referenced but not locked.
1792 * Lookup initialization/completion API
1795 hammer2_chain_lookup_init(hammer2_chain_t *parent, int flags)
1797 if (flags & HAMMER2_LOOKUP_SHARED) {
1798 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS |
1799 HAMMER2_RESOLVE_SHARED);
1801 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
1807 hammer2_chain_lookup_done(hammer2_chain_t *parent)
1810 hammer2_chain_unlock(parent);
1815 hammer2_chain_getparent(hammer2_chain_t **parentp, int how)
1817 hammer2_chain_t *oparent;
1818 hammer2_chain_t *bparent;
1819 hammer2_chain_t *nparent;
1820 hammer2_chain_core_t *above;
1823 above = oparent->above;
1825 spin_lock(&above->cst.spin);
1826 bparent = TAILQ_FIRST(&above->ownerq);
1827 hammer2_chain_ref(bparent);
1830 * Be careful of order, oparent must be unlocked before nparent
1831 * is locked below to avoid a deadlock. We might as well delay its
1832 * unlocking until we conveniently no longer have the spinlock (instead
1833 * of cycling the spinlock).
1835 * Theoretically our ref on bparent should prevent elements of the
1836 * following chain from going away and prevent above from going away,
1837 * but we still need the spinlock to safely scan the list.
1841 while (nparent->flags & HAMMER2_CHAIN_DUPLICATED)
1842 nparent = TAILQ_NEXT(nparent, core_entry);
1843 hammer2_chain_ref(nparent);
1844 spin_unlock(&above->cst.spin);
1847 hammer2_chain_unlock(oparent);
1850 hammer2_chain_lock(nparent, how | HAMMER2_RESOLVE_NOREF);
1851 hammer2_chain_drop(bparent);
1854 * We might have raced a delete-duplicate.
1856 if ((nparent->flags & HAMMER2_CHAIN_DUPLICATED) == 0)
1859 hammer2_chain_ref(bparent);
1860 hammer2_chain_unlock(nparent);
1861 spin_lock(&above->cst.spin);
1870 * Locate the first chain whos key range overlaps (key_beg, key_end) inclusive.
1871 * (*parentp) typically points to an inode but can also point to a related
1872 * indirect block and this function will recurse upwards and find the inode
1875 * (*parentp) must be exclusively locked and referenced and can be an inode
1876 * or an existing indirect block within the inode.
1878 * On return (*parentp) will be modified to point at the deepest parent chain
1879 * element encountered during the search, as a helper for an insertion or
1880 * deletion. The new (*parentp) will be locked and referenced and the old
1881 * will be unlocked and dereferenced (no change if they are both the same).
1883 * The matching chain will be returned exclusively locked. If NOLOCK is
1884 * requested the chain will be returned only referenced.
1886 * NULL is returned if no match was found, but (*parentp) will still
1887 * potentially be adjusted.
1889 * On return (*key_nextp) will point to an iterative value for key_beg.
1890 * (If NULL is returned (*key_nextp) is set to key_end).
1892 * This function will also recurse up the chain if the key is not within the
1893 * current parent's range. (*parentp) can never be set to NULL. An iteration
1894 * can simply allow (*parentp) to float inside the loop.
1896 * NOTE! chain->data is not always resolved. By default it will not be
1897 * resolved for BREF_TYPE_DATA, FREEMAP_NODE, or FREEMAP_LEAF. Use
1898 * HAMMER2_LOOKUP_ALWAYS to force resolution (but be careful w/
1899 * BREF_TYPE_DATA as the device buffer can alias the logical file
1903 hammer2_chain_lookup(hammer2_chain_t **parentp, hammer2_key_t *key_nextp,
1904 hammer2_key_t key_beg, hammer2_key_t key_end,
1905 int *cache_indexp, int flags)
1907 hammer2_mount_t *hmp;
1908 hammer2_chain_t *parent;
1909 hammer2_chain_t *chain;
1910 hammer2_blockref_t *base;
1911 hammer2_blockref_t *bref;
1912 hammer2_blockref_t bcopy;
1913 hammer2_key_t scan_beg;
1914 hammer2_key_t scan_end;
1915 hammer2_chain_core_t *above;
1917 int how_always = HAMMER2_RESOLVE_ALWAYS;
1918 int how_maybe = HAMMER2_RESOLVE_MAYBE;
1921 if (flags & HAMMER2_LOOKUP_ALWAYS) {
1922 how_maybe = how_always;
1923 how = HAMMER2_RESOLVE_ALWAYS;
1924 } else if (flags & (HAMMER2_LOOKUP_NODATA | HAMMER2_LOOKUP_NOLOCK)) {
1925 how = HAMMER2_RESOLVE_NEVER;
1927 how = HAMMER2_RESOLVE_MAYBE;
1929 if (flags & (HAMMER2_LOOKUP_SHARED | HAMMER2_LOOKUP_NOLOCK)) {
1930 how_maybe |= HAMMER2_RESOLVE_SHARED;
1931 how_always |= HAMMER2_RESOLVE_SHARED;
1932 how |= HAMMER2_RESOLVE_SHARED;
1936 * Recurse (*parentp) upward if necessary until the parent completely
1937 * encloses the key range or we hit the inode.
1939 * This function handles races against the flusher doing a delete-
1940 * duplicate above us and re-homes the parent to the duplicate in
1941 * that case, otherwise we'd wind up recursing down a stale chain.
1946 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
1947 parent->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
1948 scan_beg = parent->bref.key;
1949 scan_end = scan_beg +
1950 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
1951 if (key_beg >= scan_beg && key_end <= scan_end)
1953 parent = hammer2_chain_getparent(parentp, how_maybe);
1958 * Locate the blockref array. Currently we do a fully associative
1959 * search through the array.
1961 switch(parent->bref.type) {
1962 case HAMMER2_BREF_TYPE_INODE:
1964 * Special shortcut for embedded data returns the inode
1965 * itself. Callers must detect this condition and access
1966 * the embedded data (the strategy code does this for us).
1968 * This is only applicable to regular files and softlinks.
1970 if (parent->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
1971 if (flags & HAMMER2_LOOKUP_NOLOCK)
1972 hammer2_chain_ref(parent);
1974 hammer2_chain_lock(parent, how_always);
1975 *key_nextp = key_end + 1;
1978 base = &parent->data->ipdata.u.blockset.blockref[0];
1979 count = HAMMER2_SET_COUNT;
1981 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1982 case HAMMER2_BREF_TYPE_INDIRECT:
1984 * Handle MATCHIND on the parent
1986 if (flags & HAMMER2_LOOKUP_MATCHIND) {
1987 scan_beg = parent->bref.key;
1988 scan_end = scan_beg +
1989 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
1990 if (key_beg == scan_beg && key_end == scan_end) {
1992 hammer2_chain_lock(chain, how_maybe);
1993 *key_nextp = scan_end + 1;
1998 * Optimize indirect blocks in the INITIAL state to avoid
2001 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
2004 if (parent->data == NULL)
2005 panic("parent->data is NULL");
2006 base = &parent->data->npdata[0];
2008 count = parent->bytes / sizeof(hammer2_blockref_t);
2010 case HAMMER2_BREF_TYPE_VOLUME:
2011 base = &hmp->voldata.sroot_blockset.blockref[0];
2012 count = HAMMER2_SET_COUNT;
2014 case HAMMER2_BREF_TYPE_FREEMAP:
2015 base = &hmp->voldata.freemap_blockset.blockref[0];
2016 count = HAMMER2_SET_COUNT;
2019 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
2021 base = NULL; /* safety */
2022 count = 0; /* safety */
2026 * Merged scan to find next candidate.
2028 * hammer2_base_*() functions require the above->live_* fields
2029 * to be synchronized.
2031 * We need to hold the spinlock to access the block array and RB tree
2032 * and to interlock chain creation.
2034 above = parent->core;
2035 if ((parent->core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0)
2036 hammer2_chain_countbrefs(parent, base, count);
2041 spin_lock(&above->cst.spin);
2042 chain = hammer2_combined_find(parent, base, count,
2043 cache_indexp, key_nextp,
2044 key_beg, key_end, &bref);
2047 * Exhausted parent chain, iterate.
2050 spin_unlock(&above->cst.spin);
2051 if (key_beg == key_end) /* short cut single-key case */
2053 return (hammer2_chain_next(parentp, NULL, key_nextp,
2055 cache_indexp, flags));
2059 * Selected from blockref or in-memory chain.
2061 if (chain == NULL) {
2063 spin_unlock(&above->cst.spin);
2064 chain = hammer2_chain_get(parent, &bcopy);
2065 if (chain == NULL) {
2066 kprintf("retry lookup parent %p keys %016jx:%016jx\n",
2067 parent, key_beg, key_end);
2070 if (bcmp(&bcopy, bref, sizeof(bcopy))) {
2071 hammer2_chain_drop(chain);
2075 hammer2_chain_ref(chain);
2076 spin_unlock(&above->cst.spin);
2078 /* chain is referenced but not locked */
2081 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX)
2083 * NOTE: chain's key range is not relevant as there might be
2084 * one-offs within the range that are not deleted.
2086 if (chain->flags & HAMMER2_CHAIN_DELETED) {
2087 hammer2_chain_drop(chain);
2088 key_beg = *key_nextp;
2089 if (key_beg == 0 || key_beg > key_end)
2095 * If the chain element is an indirect block it becomes the new
2096 * parent and we loop on it. We must maintain our top-down locks
2097 * to prevent the flusher from interfering (i.e. doing a
2098 * delete-duplicate and leaving us recursing down a deleted chain).
2100 * The parent always has to be locked with at least RESOLVE_MAYBE
2101 * so we can access its data. It might need a fixup if the caller
2102 * passed incompatible flags. Be careful not to cause a deadlock
2103 * as a data-load requires an exclusive lock.
2105 * If HAMMER2_LOOKUP_MATCHIND is set and the indirect block's key
2106 * range is within the requested key range we return the indirect
2107 * block and do NOT loop. This is usually only used to acquire
2110 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
2111 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2112 hammer2_chain_lock(chain, how_maybe | HAMMER2_RESOLVE_NOREF);
2113 hammer2_chain_unlock(parent);
2114 *parentp = parent = chain;
2118 hammer2_chain_lock(chain, how | HAMMER2_RESOLVE_NOREF);
2121 * All done, return the chain
2127 * After having issued a lookup we can iterate all matching keys.
2129 * If chain is non-NULL we continue the iteration from just after it's index.
2131 * If chain is NULL we assume the parent was exhausted and continue the
2132 * iteration at the next parent.
2134 * parent must be locked on entry and remains locked throughout. chain's
2135 * lock status must match flags. Chain is always at least referenced.
2137 * WARNING! The MATCHIND flag does not apply to this function.
2140 hammer2_chain_next(hammer2_chain_t **parentp, hammer2_chain_t *chain,
2141 hammer2_key_t *key_nextp,
2142 hammer2_key_t key_beg, hammer2_key_t key_end,
2143 int *cache_indexp, int flags)
2145 hammer2_chain_t *parent;
2149 * Calculate locking flags for upward recursion.
2151 how_maybe = HAMMER2_RESOLVE_MAYBE;
2152 if (flags & (HAMMER2_LOOKUP_SHARED | HAMMER2_LOOKUP_NOLOCK))
2153 how_maybe |= HAMMER2_RESOLVE_SHARED;
2158 * Calculate the next index and recalculate the parent if necessary.
2161 key_beg = chain->bref.key +
2162 ((hammer2_key_t)1 << chain->bref.keybits);
2163 if (flags & HAMMER2_LOOKUP_NOLOCK)
2164 hammer2_chain_drop(chain);
2166 hammer2_chain_unlock(chain);
2169 * Any scan where the lookup returned degenerate data embedded
2170 * in the inode has an invalid index and must terminate.
2172 if (chain == parent)
2174 if (key_beg == 0 || key_beg > key_end)
2177 } else if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT &&
2178 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2180 * We reached the end of the iteration.
2185 * Continue iteration with next parent unless the current
2186 * parent covers the range.
2188 key_beg = parent->bref.key +
2189 ((hammer2_key_t)1 << parent->bref.keybits);
2190 if (key_beg == 0 || key_beg > key_end)
2192 parent = hammer2_chain_getparent(parentp, how_maybe);
2198 return (hammer2_chain_lookup(parentp, key_nextp,
2200 cache_indexp, flags));
2204 * Create and return a new hammer2 system memory structure of the specified
2205 * key, type and size and insert it under (*parentp). This is a full
2206 * insertion, based on the supplied key/keybits, and may involve creating
2207 * indirect blocks and moving other chains around via delete/duplicate.
2209 * (*parentp) must be exclusive locked and may be replaced on return
2210 * depending on how much work the function had to do.
2212 * (*chainp) usually starts out NULL and returns the newly created chain,
2213 * but if the caller desires the caller may allocate a disconnected chain
2214 * and pass it in instead. (It is also possible for the caller to use
2215 * chain_duplicate() to create a disconnected chain, manipulate it, then
2216 * pass it into this function to insert it).
2218 * This function should NOT be used to insert INDIRECT blocks. It is
2219 * typically used to create/insert inodes and data blocks.
2221 * Caller must pass-in an exclusively locked parent the new chain is to
2222 * be inserted under, and optionally pass-in a disconnected, exclusively
2223 * locked chain to insert (else we create a new chain). The function will
2224 * adjust (*parentp) as necessary, create or connect the chain, and
2225 * return an exclusively locked chain in *chainp.
2228 hammer2_chain_create(hammer2_trans_t *trans, hammer2_chain_t **parentp,
2229 hammer2_chain_t **chainp,
2230 hammer2_key_t key, int keybits, int type, size_t bytes)
2232 hammer2_mount_t *hmp;
2233 hammer2_chain_t *chain;
2234 hammer2_chain_t *parent = *parentp;
2235 hammer2_chain_core_t *above;
2236 hammer2_blockref_t *base;
2237 hammer2_blockref_t dummy;
2242 above = parent->core;
2243 KKASSERT(ccms_thread_lock_owned(&above->cst));
2247 if (chain == NULL) {
2249 * First allocate media space and construct the dummy bref,
2250 * then allocate the in-memory chain structure. Set the
2251 * INITIAL flag for fresh chains which do not have embedded
2254 bzero(&dummy, sizeof(dummy));
2257 dummy.keybits = keybits;
2258 dummy.data_off = hammer2_getradix(bytes);
2259 dummy.methods = parent->bref.methods;
2260 chain = hammer2_chain_alloc(hmp, parent->pmp, trans, &dummy);
2261 hammer2_chain_core_alloc(trans, chain, NULL);
2264 * Lock the chain manually, chain_lock will load the chain
2265 * which we do NOT want to do. (note: chain->refs is set
2266 * to 1 by chain_alloc() for us, but lockcnt is not).
2269 ccms_thread_lock(&chain->core->cst, CCMS_STATE_EXCLUSIVE);
2273 * We do NOT set INITIAL here (yet). INITIAL is only
2274 * used for indirect blocks.
2276 * Recalculate bytes to reflect the actual media block
2279 bytes = (hammer2_off_t)1 <<
2280 (int)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
2281 chain->bytes = bytes;
2284 case HAMMER2_BREF_TYPE_VOLUME:
2285 case HAMMER2_BREF_TYPE_FREEMAP:
2286 panic("hammer2_chain_create: called with volume type");
2288 case HAMMER2_BREF_TYPE_INODE:
2289 KKASSERT(bytes == HAMMER2_INODE_BYTES);
2290 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
2291 chain->data = kmalloc(sizeof(chain->data->ipdata),
2292 hmp->mchain, M_WAITOK | M_ZERO);
2294 case HAMMER2_BREF_TYPE_INDIRECT:
2295 panic("hammer2_chain_create: cannot be used to"
2296 "create indirect block");
2298 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2299 panic("hammer2_chain_create: cannot be used to"
2300 "create freemap root or node");
2302 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2303 KKASSERT(bytes == sizeof(chain->data->bmdata));
2304 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
2305 chain->data = kmalloc(sizeof(chain->data->bmdata),
2306 hmp->mchain, M_WAITOK | M_ZERO);
2308 case HAMMER2_BREF_TYPE_DATA:
2311 * leave chain->data NULL, set INITIAL
2313 KKASSERT(chain->data == NULL);
2314 atomic_set_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
2319 * Potentially update the existing chain's key/keybits.
2321 * Do NOT mess with the current state of the INITIAL flag.
2323 chain->bref.key = key;
2324 chain->bref.keybits = keybits;
2325 KKASSERT(chain->above == NULL);
2329 * Calculate how many entries we have in the blockref array and
2330 * determine if an indirect block is required.
2333 above = parent->core;
2335 switch(parent->bref.type) {
2336 case HAMMER2_BREF_TYPE_INODE:
2337 KKASSERT((parent->data->ipdata.op_flags &
2338 HAMMER2_OPFLAG_DIRECTDATA) == 0);
2339 KKASSERT(parent->data != NULL);
2340 base = &parent->data->ipdata.u.blockset.blockref[0];
2341 count = HAMMER2_SET_COUNT;
2343 case HAMMER2_BREF_TYPE_INDIRECT:
2344 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2345 if (parent->flags & HAMMER2_CHAIN_INITIAL)
2348 base = &parent->data->npdata[0];
2349 count = parent->bytes / sizeof(hammer2_blockref_t);
2351 case HAMMER2_BREF_TYPE_VOLUME:
2352 KKASSERT(parent->data != NULL);
2353 base = &hmp->voldata.sroot_blockset.blockref[0];
2354 count = HAMMER2_SET_COUNT;
2356 case HAMMER2_BREF_TYPE_FREEMAP:
2357 KKASSERT(parent->data != NULL);
2358 base = &hmp->voldata.freemap_blockset.blockref[0];
2359 count = HAMMER2_SET_COUNT;
2362 panic("hammer2_chain_create: unrecognized blockref type: %d",
2370 * Make sure we've counted the brefs
2372 if ((parent->core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0)
2373 hammer2_chain_countbrefs(parent, base, count);
2375 KKASSERT(above->live_count >= 0 && above->live_count <= count);
2378 * If no free blockref could be found we must create an indirect
2379 * block and move a number of blockrefs into it. With the parent
2380 * locked we can safely lock each child in order to delete+duplicate
2381 * it without causing a deadlock.
2383 * This may return the new indirect block or the old parent depending
2384 * on where the key falls. NULL is returned on error.
2386 if (above->live_count == count) {
2387 hammer2_chain_t *nparent;
2389 nparent = hammer2_chain_create_indirect(trans, parent,
2392 if (nparent == NULL) {
2394 hammer2_chain_drop(chain);
2398 if (parent != nparent) {
2399 hammer2_chain_unlock(parent);
2400 parent = *parentp = nparent;
2406 * Link the chain into its parent. Later on we will have to set
2407 * the MOVED bit in situations where we don't mark the new chain
2408 * as being modified.
2410 if (chain->above != NULL)
2411 panic("hammer2: hammer2_chain_create: chain already connected");
2412 KKASSERT(chain->above == NULL);
2413 KKASSERT((chain->flags & HAMMER2_CHAIN_DELETED) == 0);
2414 hammer2_chain_insert(above, NULL, chain,
2415 HAMMER2_CHAIN_INSERT_SPIN |
2416 HAMMER2_CHAIN_INSERT_LIVE);
2420 * Mark the newly created chain modified.
2422 * Device buffers are not instantiated for DATA elements
2423 * as these are handled by logical buffers.
2425 * Indirect and freemap node indirect blocks are handled
2426 * by hammer2_chain_create_indirect() and not by this
2429 * Data for all other bref types is expected to be
2430 * instantiated (INODE, LEAF).
2432 switch(chain->bref.type) {
2433 case HAMMER2_BREF_TYPE_DATA:
2434 hammer2_chain_modify(trans, &chain,
2435 HAMMER2_MODIFY_OPTDATA |
2436 HAMMER2_MODIFY_ASSERTNOCOPY);
2438 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2439 case HAMMER2_BREF_TYPE_INODE:
2440 hammer2_chain_modify(trans, &chain,
2441 HAMMER2_MODIFY_ASSERTNOCOPY);
2445 * Remaining types are not supported by this function.
2446 * In particular, INDIRECT and LEAF_NODE types are
2447 * handled by create_indirect().
2449 panic("hammer2_chain_create: bad type: %d",
2456 * When reconnecting a chain we must set MOVED and setsubmod
2457 * so the flush recognizes that it must update the bref in
2460 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2461 hammer2_chain_ref(chain);
2462 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
2465 hammer2_chain_setsubmod(trans, chain);
2474 * Replace (*chainp) with a duplicate in-memory chain structure which shares
2475 * the same core and media state as the orignal. The original *chainp is
2476 * unlocked and the replacement will be returned locked.
2478 * The old chain may or may not be in a DELETED state. This new chain will
2479 * be live (not deleted).
2481 * The new chain will be marked modified for the current transaction.
2483 * If (parent) is non-NULL then the new duplicated chain is inserted under
2486 * If (parent) is NULL then the new duplicated chain is not inserted anywhere,
2487 * similar to if it had just been chain_alloc()'d (suitable for passing into
2488 * hammer2_chain_create() after this function returns).
2490 * WARNING! This is not a snapshot. Changes made underneath either the old
2491 * or new chain will affect both.
2493 static void hammer2_chain_dup_fixup(hammer2_chain_t *ochain,
2494 hammer2_chain_t *nchain);
2497 hammer2_chain_duplicate(hammer2_trans_t *trans, hammer2_chain_t **parentp,
2498 hammer2_chain_t **chainp, hammer2_blockref_t *bref,
2501 hammer2_mount_t *hmp;
2502 hammer2_chain_t *parent;
2503 hammer2_chain_t *ochain;
2504 hammer2_chain_t *nchain;
2505 hammer2_chain_core_t *above;
2509 * We want nchain to be our go-to live chain, but ochain may be in
2510 * a MODIFIED state within the current flush synchronization segment.
2511 * Force any further modifications of ochain to do another COW
2512 * operation even if modify_tid indicates that one is not needed.
2514 * WARNING! We should never resolve DATA to device buffers
2515 * (XXX allow it if the caller did?), and since
2516 * we currently do not have the logical buffer cache
2517 * buffer in-hand to fix its cached physical offset
2518 * we also force the modify code to not COW it. XXX
2523 ochain->debug_reason += 0x10000;
2525 ochain->debug_reason += 0x100000;
2528 if (ochain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2529 hammer2_chain_modify(trans, &ochain,
2530 HAMMER2_MODIFY_OPTDATA |
2531 HAMMER2_MODIFY_NOREALLOC);
2532 } else if (ochain->flags & HAMMER2_CHAIN_INITIAL) {
2533 hammer2_chain_modify(trans, &ochain,
2534 HAMMER2_MODIFY_OPTDATA);
2536 hammer2_chain_modify(trans, &ochain, 0);
2539 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_FORCECOW);
2542 * Now create a duplicate of the chain structure, associating
2543 * it with the same core, making it the same size, pointing it
2544 * to the same bref (the same media block).
2546 * Give the duplicate the same modify_tid that we previously
2547 * ensured was sufficiently advanced to trigger a block table
2548 * insertion on flush.
2550 * NOTE: bref.mirror_tid duplicated by virtue of bref copy in
2551 * hammer2_chain_alloc()
2554 bref = &ochain->bref;
2556 nchain = hammer2_chain_alloc(hmp, NULL, trans, bref);
2557 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_SNAPSHOT);
2559 nchain = hammer2_chain_alloc(hmp, ochain->pmp, trans, bref);
2561 hammer2_chain_core_alloc(trans, nchain, ochain);
2562 bytes = (hammer2_off_t)1 <<
2563 (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
2564 nchain->bytes = bytes;
2565 nchain->modify_tid = ochain->modify_tid;
2566 if (ochain->flags & HAMMER2_CHAIN_INITIAL)
2567 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_INITIAL);
2570 * Fixup (copy) any embedded data. Non-embedded data relies on the
2571 * media block. We must unlock ochain before we can access nchain's
2572 * media block because they might share the same bp and deadlock if
2575 hammer2_chain_lock(nchain, HAMMER2_RESOLVE_NEVER |
2576 HAMMER2_RESOLVE_NOREF);
2577 hammer2_chain_dup_fixup(ochain, nchain);
2578 /* nchain has 1 ref */
2579 hammer2_chain_unlock(ochain);
2580 KKASSERT((ochain->flags & HAMMER2_CHAIN_EMBEDDED) ||
2581 ochain->data == NULL);
2584 * Place nchain in the modified state, instantiate media data
2585 * if necessary. Because modify_tid is already completely
2586 * synchronized this should not result in a delete-duplicate.
2588 * We want nchain at the target to look like a new insertion.
2589 * Forcing the modification to be INPLACE accomplishes this
2590 * because we get the same nchain with an updated modify_tid.
2592 if (nchain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2593 hammer2_chain_modify(trans, &nchain,
2594 HAMMER2_MODIFY_OPTDATA |
2595 HAMMER2_MODIFY_NOREALLOC |
2596 HAMMER2_MODIFY_INPLACE);
2597 } else if (nchain->flags & HAMMER2_CHAIN_INITIAL) {
2598 hammer2_chain_modify(trans, &nchain,
2599 HAMMER2_MODIFY_OPTDATA |
2600 HAMMER2_MODIFY_INPLACE);
2602 hammer2_chain_modify(trans, &nchain,
2603 HAMMER2_MODIFY_INPLACE);
2607 * If parent is not NULL the duplicated chain will be entered under
2608 * the parent and the MOVED bit set.
2610 * Having both chains locked is extremely important for atomicy.
2612 if (parentp && (parent = *parentp) != NULL) {
2613 above = parent->core;
2614 KKASSERT(ccms_thread_lock_owned(&above->cst));
2615 KKASSERT((nchain->flags & HAMMER2_CHAIN_DELETED) == 0);
2616 KKASSERT(parent->refs > 0);
2618 hammer2_chain_create(trans, parentp, &nchain,
2619 nchain->bref.key, nchain->bref.keybits,
2620 nchain->bref.type, nchain->bytes);
2623 if ((nchain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2624 hammer2_chain_ref(nchain);
2625 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_MOVED);
2627 hammer2_chain_setsubmod(trans, nchain);
2632 * Unconditionally set MOVED to force the parent blockrefs to
2633 * update, and adjust update_hi below nchain so nchain's
2634 * blockrefs are updated with the new attachment.
2636 if (nchain->core->update_hi < trans->sync_tid) {
2637 spin_lock(&nchain->core->cst.spin);
2638 if (nchain->core->update_hi < trans->sync_tid)
2639 nchain->core->update_hi = trans->sync_tid;
2640 spin_unlock(&nchain->core->cst.spin);
2648 * Special in-place delete-duplicate sequence which does not require a
2649 * locked parent. (*chainp) is marked DELETED and atomically replaced
2650 * with a duplicate. Atomicy is at the very-fine spin-lock level in
2651 * order to ensure that lookups do not race us.
2653 * If the old chain is already marked deleted the new chain will also be
2654 * marked deleted. This case can occur when an inode is removed from the
2655 * filesystem but programs still have an open descriptor to it, and during
2656 * flushes when the flush needs to operate on a chain that is deleted in
2657 * the live view but still alive in the flush view.
2659 * The new chain will be marked modified for the current transaction.
2662 hammer2_chain_delete_duplicate(hammer2_trans_t *trans, hammer2_chain_t **chainp,
2665 hammer2_mount_t *hmp;
2666 hammer2_chain_t *ochain;
2667 hammer2_chain_t *nchain;
2668 hammer2_chain_core_t *above;
2671 if (hammer2_debug & 0x20000)
2675 * Note that we do not have to call setsubmod on ochain, calling it
2676 * on nchain is sufficient.
2681 ochain->debug_reason += 0x1000;
2682 if ((ochain->debug_reason & 0xF000) > 0x4000) {
2683 kprintf("ochain %p\n", ochain);
2686 if (ochain->bref.type == HAMMER2_BREF_TYPE_INODE) {
2687 KKASSERT(ochain->data);
2691 * First create a duplicate of the chain structure.
2692 * (nchain is allocated with one ref).
2694 * In the case where nchain inherits ochains core, nchain is
2695 * effectively locked due to ochain being locked (and sharing the
2696 * core), until we can give nchain its own official ock.
2698 nchain = hammer2_chain_alloc(hmp, ochain->pmp, trans, &ochain->bref);
2699 if (flags & HAMMER2_DELDUP_RECORE)
2700 hammer2_chain_core_alloc(trans, nchain, NULL);
2702 hammer2_chain_core_alloc(trans, nchain, ochain);
2703 above = ochain->above;
2705 bytes = (hammer2_off_t)1 <<
2706 (int)(ochain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
2707 nchain->bytes = bytes;
2710 * Duplicate inherits ochain's live state including its modification
2711 * state. This function disposes of the original. Because we are
2712 * doing this in-place under the same parent the block array
2713 * inserted/deleted state does not change.
2715 * The caller isn't expected to make further modifications of ochain
2716 * but set the FORCECOW bit anyway, just in case it does. If ochain
2717 * was previously marked FORCECOW we also flag nchain FORCECOW
2718 * (used during hardlink splits).
2720 * NOTE: bref.mirror_tid duplicated by virtue of bref copy in
2721 * hammer2_chain_alloc()
2723 nchain->data_count += ochain->data_count;
2724 nchain->inode_count += ochain->inode_count;
2725 atomic_set_int(&nchain->flags,
2726 ochain->flags & (HAMMER2_CHAIN_INITIAL |
2727 HAMMER2_CHAIN_FORCECOW));
2728 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_FORCECOW);
2731 * Lock nchain so both chains are now locked (extremely important
2732 * for atomicy). Mark ochain deleted and reinsert into the topology
2733 * and insert nchain all in one go.
2735 * If the ochain is already deleted it is left alone and nchain
2736 * is inserted into the topology as a deleted chain. This is
2737 * important because it allows ongoing operations to be executed
2738 * on a deleted inode which still has open descriptors.
2740 * The deleted case can also occur when a flush delete-duplicates
2741 * a node which is being concurrently modified by ongoing operations
2742 * in a later transaction. This creates a problem because the flush
2743 * is intended to update blockrefs which then propagate, allowing
2744 * the original covering in-memory chains to be freed up. In this
2745 * situation the flush code does NOT free the original covering
2746 * chains and will re-apply them to successive copies.
2748 hammer2_chain_lock(nchain, HAMMER2_RESOLVE_NEVER);
2749 hammer2_chain_dup_fixup(ochain, nchain);
2750 /* extra ref still present from original allocation */
2752 KKASSERT(ochain->flags & HAMMER2_CHAIN_ONRBTREE);
2753 spin_lock(&above->cst.spin);
2754 KKASSERT(ochain->flags & HAMMER2_CHAIN_ONRBTREE);
2757 * Ultimately nchain->modify_tid will be set to trans->sync_tid,
2758 * but we can't do that here because we want to call
2759 * hammer2_chain_modify() to reallocate the block (if necessary).
2761 nchain->modify_tid = ochain->modify_tid;
2763 if (ochain->flags & HAMMER2_CHAIN_DELETED) {
2764 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_DELETED);
2765 if (ochain->delete_tid > trans->sync_tid) {
2767 * delete-duplicate a chain deleted in a later
2768 * transaction. Only allowed on chains created
2769 * before or during the current transaction (flush
2770 * code should filter out chains created after the
2771 * current transaction).
2773 * To make this work is a bit of a hack. We convert
2774 * ochain's delete_tid to the current sync_tid and
2775 * create a nchain which sets up ochains original
2778 * This effectively forces ochain to flush as a
2779 * deletion and nchain as a creation. Thus MOVED
2780 * must be set in ochain (it should already be
2781 * set since it's original delete_tid could not
2782 * have been flushed yet). Since ochain's delete_tid
2783 * has been moved down to sync_tid, a re-flush at
2784 * sync_tid won't try to delete-duplicate ochain
2787 KKASSERT(ochain->modify_tid <= trans->sync_tid);
2788 nchain->delete_tid = ochain->delete_tid;
2789 ochain->delete_tid = trans->sync_tid;
2790 KKASSERT(ochain->flags & HAMMER2_CHAIN_MOVED);
2791 } else if (ochain->delete_tid == trans->sync_tid) {
2793 * ochain was deleted in the current transaction
2795 nchain->delete_tid = trans->sync_tid;
2798 * ochain was deleted in a prior transaction.
2799 * create and delete nchain in the current
2802 nchain->delete_tid = trans->sync_tid;
2804 hammer2_chain_insert(above, ochain->inlayer, nchain, 0);
2806 KKASSERT(trans->sync_tid >= ochain->modify_tid);
2807 ochain->delete_tid = trans->sync_tid;
2808 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_DELETED);
2809 atomic_add_int(&above->live_count, -1);
2810 hammer2_chain_insert(above, NULL, nchain,
2811 HAMMER2_CHAIN_INSERT_LIVE);
2814 if ((ochain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2815 hammer2_chain_ref(ochain);
2816 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_MOVED);
2818 spin_unlock(&above->cst.spin);
2821 * ochain must be unlocked because ochain and nchain might share
2822 * a buffer cache buffer, so we need to release it so nchain can
2823 * potentially obtain it.
2825 hammer2_chain_unlock(ochain);
2828 * Finishing fixing up nchain. A new block will be allocated if
2829 * crossing a synchronization point (meta-data only).
2831 if (nchain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2832 hammer2_chain_modify(trans, &nchain,
2833 HAMMER2_MODIFY_OPTDATA |
2834 HAMMER2_MODIFY_NOREALLOC |
2835 HAMMER2_MODIFY_INPLACE);
2836 } else if (nchain->flags & HAMMER2_CHAIN_INITIAL) {
2837 hammer2_chain_modify(trans, &nchain,
2838 HAMMER2_MODIFY_OPTDATA |
2839 HAMMER2_MODIFY_INPLACE);
2841 hammer2_chain_modify(trans, &nchain,
2842 HAMMER2_MODIFY_INPLACE);
2844 hammer2_chain_drop(nchain);
2847 * Unconditionally set MOVED to force the parent blockrefs to
2848 * update as the chain_modify() above won't necessarily do it.
2850 * Adjust update_hi below nchain so nchain's blockrefs are updated
2851 * with the new attachment.
2853 if ((nchain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2854 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_MOVED);
2855 hammer2_chain_ref(nchain);
2858 if (nchain->core->update_hi < trans->sync_tid) {
2859 spin_lock(&nchain->core->cst.spin);
2860 if (nchain->core->update_hi < trans->sync_tid)
2861 nchain->core->update_hi = trans->sync_tid;
2862 spin_unlock(&nchain->core->cst.spin);
2865 hammer2_chain_setsubmod(trans, nchain);
2870 * Helper function to fixup inodes. The caller procedure stack may hold
2871 * multiple locks on ochain if it represents an inode, preventing our
2872 * unlock from retiring its state to the buffer cache.
2874 * In this situation any attempt to access the buffer cache could result
2875 * either in stale data or a deadlock. Work around the problem by copying
2876 * the embedded data directly.
2880 hammer2_chain_dup_fixup(hammer2_chain_t *ochain, hammer2_chain_t *nchain)
2882 if (ochain->data == NULL)
2884 switch(ochain->bref.type) {
2885 case HAMMER2_BREF_TYPE_INODE:
2886 KKASSERT(nchain->data == NULL);
2887 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_EMBEDDED);
2888 nchain->data = kmalloc(sizeof(nchain->data->ipdata),
2889 ochain->hmp->mchain, M_WAITOK | M_ZERO);
2890 nchain->data->ipdata = ochain->data->ipdata;
2892 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2893 KKASSERT(nchain->data == NULL);
2894 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_EMBEDDED);
2895 nchain->data = kmalloc(sizeof(nchain->data->bmdata),
2896 ochain->hmp->mchain, M_WAITOK | M_ZERO);
2897 bcopy(ochain->data->bmdata,
2898 nchain->data->bmdata,
2899 sizeof(nchain->data->bmdata));
2907 * Create a snapshot of the specified {parent, ochain} with the specified
2908 * label. The originating hammer2_inode must be exclusively locked for
2911 * The ioctl code has already synced the filesystem.
2914 hammer2_chain_snapshot(hammer2_trans_t *trans, hammer2_chain_t **ochainp,
2915 hammer2_ioc_pfs_t *pfs)
2917 hammer2_mount_t *hmp;
2918 hammer2_chain_t *ochain = *ochainp;
2919 hammer2_chain_t *nchain;
2920 hammer2_inode_data_t *ipdata;
2921 hammer2_inode_t *nip;
2928 kprintf("snapshot %s ochain->refs %d ochain->flags %08x\n",
2929 pfs->name, ochain->refs, ochain->flags);
2931 name_len = strlen(pfs->name);
2932 lhc = hammer2_dirhash(pfs->name, name_len);
2935 opfs_clid = ochain->data->ipdata.pfs_clid;
2940 * Create the snapshot directory under the super-root
2942 * Set PFS type, generate a unique filesystem id, and generate
2943 * a cluster id. Use the same clid when snapshotting a PFS root,
2944 * which theoretically allows the snapshot to be used as part of
2945 * the same cluster (perhaps as a cache).
2947 * Copy the (flushed) ochain's blockref array. Theoretically we
2948 * could use chain_duplicate() but it becomes difficult to disentangle
2949 * the shared core so for now just brute-force it.
2955 nip = hammer2_inode_create(trans, hmp->sroot, &vat, proc0.p_ucred,
2956 pfs->name, name_len, &nchain, &error);
2959 ipdata = hammer2_chain_modify_ip(trans, nip, &nchain, 0);
2960 ipdata->pfs_type = HAMMER2_PFSTYPE_SNAPSHOT;
2961 kern_uuidgen(&ipdata->pfs_fsid, 1);
2962 if (ochain->flags & HAMMER2_CHAIN_PFSROOT)
2963 ipdata->pfs_clid = opfs_clid;
2965 kern_uuidgen(&ipdata->pfs_clid, 1);
2966 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_PFSROOT);
2967 ipdata->u.blockset = ochain->data->ipdata.u.blockset;
2969 hammer2_inode_unlock_ex(nip, nchain);
2975 * Create an indirect block that covers one or more of the elements in the
2976 * current parent. Either returns the existing parent with no locking or
2977 * ref changes or returns the new indirect block locked and referenced
2978 * and leaving the original parent lock/ref intact as well.
2980 * If an error occurs, NULL is returned and *errorp is set to the error.
2982 * The returned chain depends on where the specified key falls.
2984 * The key/keybits for the indirect mode only needs to follow three rules:
2986 * (1) That all elements underneath it fit within its key space and
2988 * (2) That all elements outside it are outside its key space.
2990 * (3) When creating the new indirect block any elements in the current
2991 * parent that fit within the new indirect block's keyspace must be
2992 * moved into the new indirect block.
2994 * (4) The keyspace chosen for the inserted indirect block CAN cover a wider
2995 * keyspace the the current parent, but lookup/iteration rules will
2996 * ensure (and must ensure) that rule (2) for all parents leading up
2997 * to the nearest inode or the root volume header is adhered to. This
2998 * is accomplished by always recursing through matching keyspaces in
2999 * the hammer2_chain_lookup() and hammer2_chain_next() API.
3001 * The current implementation calculates the current worst-case keyspace by
3002 * iterating the current parent and then divides it into two halves, choosing
3003 * whichever half has the most elements (not necessarily the half containing
3004 * the requested key).
3006 * We can also opt to use the half with the least number of elements. This
3007 * causes lower-numbered keys (aka logical file offsets) to recurse through
3008 * fewer indirect blocks and higher-numbered keys to recurse through more.
3009 * This also has the risk of not moving enough elements to the new indirect
3010 * block and being forced to create several indirect blocks before the element
3013 * Must be called with an exclusively locked parent.
3015 static int hammer2_chain_indkey_freemap(hammer2_chain_t *parent,
3016 hammer2_key_t *keyp, int keybits,
3017 hammer2_blockref_t *base, int count);
3018 static int hammer2_chain_indkey_normal(hammer2_chain_t *parent,
3019 hammer2_key_t *keyp, int keybits,
3020 hammer2_blockref_t *base, int count);
3023 hammer2_chain_create_indirect(hammer2_trans_t *trans, hammer2_chain_t *parent,
3024 hammer2_key_t create_key, int create_bits,
3025 int for_type, int *errorp)
3027 hammer2_mount_t *hmp;
3028 hammer2_chain_core_t *above;
3029 hammer2_chain_core_t *icore;
3030 hammer2_blockref_t *base;
3031 hammer2_blockref_t *bref;
3032 hammer2_blockref_t bcopy;
3033 hammer2_chain_t *chain;
3034 hammer2_chain_t *ichain;
3035 hammer2_chain_t dummy;
3036 hammer2_key_t key = create_key;
3037 hammer2_key_t key_beg;
3038 hammer2_key_t key_end;
3039 hammer2_key_t key_next;
3040 int keybits = create_bits;
3047 * Calculate the base blockref pointer or NULL if the chain
3048 * is known to be empty. We need to calculate the array count
3049 * for RB lookups either way.
3053 KKASSERT(ccms_thread_lock_owned(&parent->core->cst));
3054 above = parent->core;
3056 /*hammer2_chain_modify(trans, &parent, HAMMER2_MODIFY_OPTDATA);*/
3057 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
3060 switch(parent->bref.type) {
3061 case HAMMER2_BREF_TYPE_INODE:
3062 count = HAMMER2_SET_COUNT;
3064 case HAMMER2_BREF_TYPE_INDIRECT:
3065 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3066 count = parent->bytes / sizeof(hammer2_blockref_t);
3068 case HAMMER2_BREF_TYPE_VOLUME:
3069 count = HAMMER2_SET_COUNT;
3071 case HAMMER2_BREF_TYPE_FREEMAP:
3072 count = HAMMER2_SET_COUNT;
3075 panic("hammer2_chain_create_indirect: "
3076 "unrecognized blockref type: %d",
3082 switch(parent->bref.type) {
3083 case HAMMER2_BREF_TYPE_INODE:
3084 base = &parent->data->ipdata.u.blockset.blockref[0];
3085 count = HAMMER2_SET_COUNT;
3087 case HAMMER2_BREF_TYPE_INDIRECT:
3088 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3089 base = &parent->data->npdata[0];
3090 count = parent->bytes / sizeof(hammer2_blockref_t);
3092 case HAMMER2_BREF_TYPE_VOLUME:
3093 base = &hmp->voldata.sroot_blockset.blockref[0];
3094 count = HAMMER2_SET_COUNT;
3096 case HAMMER2_BREF_TYPE_FREEMAP:
3097 base = &hmp->voldata.freemap_blockset.blockref[0];
3098 count = HAMMER2_SET_COUNT;
3101 panic("hammer2_chain_create_indirect: "
3102 "unrecognized blockref type: %d",
3110 * dummy used in later chain allocation (no longer used for lookups).
3112 bzero(&dummy, sizeof(dummy));
3113 dummy.delete_tid = HAMMER2_MAX_TID;
3116 * When creating an indirect block for a freemap node or leaf
3117 * the key/keybits must be fitted to static radix levels because
3118 * particular radix levels use particular reserved blocks in the
3121 * This routine calculates the key/radix of the indirect block
3122 * we need to create, and whether it is on the high-side or the
3125 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
3126 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
3127 keybits = hammer2_chain_indkey_freemap(parent, &key, keybits,
3130 keybits = hammer2_chain_indkey_normal(parent, &key, keybits,
3135 * Normalize the key for the radix being represented, keeping the
3136 * high bits and throwing away the low bits.
3138 key &= ~(((hammer2_key_t)1 << keybits) - 1);
3141 * How big should our new indirect block be? It has to be at least
3142 * as large as its parent.
3144 if (parent->bref.type == HAMMER2_BREF_TYPE_INODE)
3145 nbytes = HAMMER2_IND_BYTES_MIN;
3147 nbytes = HAMMER2_IND_BYTES_MAX;
3148 if (nbytes < count * sizeof(hammer2_blockref_t))
3149 nbytes = count * sizeof(hammer2_blockref_t);
3152 * Ok, create our new indirect block
3154 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
3155 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
3156 dummy.bref.type = HAMMER2_BREF_TYPE_FREEMAP_NODE;
3158 dummy.bref.type = HAMMER2_BREF_TYPE_INDIRECT;
3160 dummy.bref.key = key;
3161 dummy.bref.keybits = keybits;
3162 dummy.bref.data_off = hammer2_getradix(nbytes);
3163 dummy.bref.methods = parent->bref.methods;
3165 ichain = hammer2_chain_alloc(hmp, parent->pmp, trans, &dummy.bref);
3166 atomic_set_int(&ichain->flags, HAMMER2_CHAIN_INITIAL);
3167 hammer2_chain_core_alloc(trans, ichain, NULL);
3168 icore = ichain->core;
3169 hammer2_chain_lock(ichain, HAMMER2_RESOLVE_MAYBE);
3170 hammer2_chain_drop(ichain); /* excess ref from alloc */
3173 * We have to mark it modified to allocate its block, but use
3174 * OPTDATA to allow it to remain in the INITIAL state. Otherwise
3175 * it won't be acted upon by the flush code.
3177 * XXX leave the node unmodified, depend on the update_hi
3178 * flush to assign and modify parent blocks.
3180 hammer2_chain_modify(trans, &ichain, HAMMER2_MODIFY_OPTDATA);
3183 * Iterate the original parent and move the matching brefs into
3184 * the new indirect block.
3186 * XXX handle flushes.
3189 key_end = HAMMER2_MAX_KEY;
3191 spin_lock(&above->cst.spin);
3195 if (++loops > 8192) {
3196 spin_unlock(&above->cst.spin);
3197 panic("shit parent=%p base/count %p:%d\n",
3198 parent, base, count);
3202 * NOTE: spinlock stays intact, returned chain (if not NULL)
3203 * is not referenced or locked which means that we
3204 * cannot safely check its flagged / deletion status
3207 chain = hammer2_combined_find(parent, base, count,
3208 &cache_index, &key_next,
3213 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3216 * Skip keys that are not within the key/radix of the new
3217 * indirect block. They stay in the parent.
3219 if ((~(((hammer2_key_t)1 << keybits) - 1) &
3220 (key ^ bref->key)) != 0) {
3221 goto next_key_spinlocked;
3225 * Load the new indirect block by acquiring the related
3226 * chains (potentially from media as it might not be
3227 * in-memory). Then move it to the new parent (ichain)
3228 * via DELETE-DUPLICATE.
3232 * Use chain already present in the RBTREE
3234 hammer2_chain_ref(chain);
3235 spin_unlock(&above->cst.spin);
3236 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER |
3237 HAMMER2_RESOLVE_NOREF);
3240 * Get chain for blockref element. _get returns NULL
3241 * on insertion race.
3244 spin_unlock(&above->cst.spin);
3245 chain = hammer2_chain_get(parent, bref);
3246 if (chain == NULL) {
3247 spin_lock(&above->cst.spin);
3250 if (bcmp(&bcopy, bref, sizeof(bcopy))) {
3251 hammer2_chain_drop(chain);
3252 spin_lock(&above->cst.spin);
3255 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER |
3256 HAMMER2_RESOLVE_NOREF);
3260 * This is always live so if the chain has been delete-
3261 * duplicated we raced someone and we have to retry.
3263 * If a terminal (i.e. not duplicated) chain has been
3264 * deleted we move on to the next key.
3266 if (chain->flags & HAMMER2_CHAIN_DUPLICATED) {
3267 hammer2_chain_unlock(chain);
3268 spin_lock(&above->cst.spin);
3271 if (chain->flags & HAMMER2_CHAIN_DELETED) {
3272 hammer2_chain_unlock(chain);
3277 * Shift the chain to the indirect block.
3279 hammer2_chain_delete(trans, chain, HAMMER2_DELETE_WILLDUP);
3280 hammer2_chain_duplicate(trans, &ichain, &chain, NULL, 0);
3281 hammer2_chain_unlock(chain);
3282 KKASSERT(parent->refs > 0);
3285 spin_lock(&above->cst.spin);
3286 next_key_spinlocked:
3287 if (key_next == 0 || key_next > key_end)
3291 spin_unlock(&above->cst.spin);
3294 * Insert the new indirect block into the parent now that we've
3295 * cleared out some entries in the parent. We calculated a good
3296 * insertion index in the loop above (ichain->index).
3298 * We don't have to set MOVED here because we mark ichain modified
3299 * down below (so the normal modified -> flush -> set-moved sequence
3302 * The insertion shouldn't race as this is a completely new block
3303 * and the parent is locked.
3305 KKASSERT((ichain->flags & HAMMER2_CHAIN_ONRBTREE) == 0);
3306 hammer2_chain_insert(above, NULL, ichain,
3307 HAMMER2_CHAIN_INSERT_SPIN |
3308 HAMMER2_CHAIN_INSERT_LIVE);
3311 * Mark the new indirect block modified after insertion, which
3312 * will propagate up through parent all the way to the root and
3313 * also allocate the physical block in ichain for our caller,
3314 * and assign ichain->data to a pre-zero'd space (because there
3315 * is not prior data to copy into it).
3317 * We have to set update_hi in ichain's flags manually so the
3318 * flusher knows it has to recurse through it to get to all of
3319 * our moved blocks, then call setsubmod() to set the bit
3322 /*hammer2_chain_modify(trans, &ichain, HAMMER2_MODIFY_OPTDATA);*/
3323 if (ichain->core->update_hi < trans->sync_tid) {
3324 spin_lock(&ichain->core->cst.spin);
3325 if (ichain->core->update_hi < trans->sync_tid)
3326 ichain->core->update_hi = trans->sync_tid;
3327 spin_unlock(&ichain->core->cst.spin);
3329 hammer2_chain_setsubmod(trans, ichain);
3332 * Figure out what to return.
3334 if (~(((hammer2_key_t)1 << keybits) - 1) &
3335 (create_key ^ key)) {
3337 * Key being created is outside the key range,
3338 * return the original parent.
3340 hammer2_chain_unlock(ichain);
3343 * Otherwise its in the range, return the new parent.
3344 * (leave both the new and old parent locked).
3353 * Calculate the keybits and highside/lowside of the freemap node the
3354 * caller is creating.
3356 * This routine will specify the next higher-level freemap key/radix
3357 * representing the lowest-ordered set. By doing so, eventually all
3358 * low-ordered sets will be moved one level down.
3360 * We have to be careful here because the freemap reserves a limited
3361 * number of blocks for a limited number of levels. So we can't just
3362 * push indiscriminately.
3365 hammer2_chain_indkey_freemap(hammer2_chain_t *parent, hammer2_key_t *keyp,
3366 int keybits, hammer2_blockref_t *base, int count)
3368 hammer2_chain_core_t *above;
3369 hammer2_chain_t *chain;
3370 hammer2_blockref_t *bref;
3372 hammer2_key_t key_beg;
3373 hammer2_key_t key_end;
3374 hammer2_key_t key_next;
3381 above = parent->core;
3387 * Calculate the range of keys in the array being careful to skip
3388 * slots which are overridden with a deletion.
3391 key_end = HAMMER2_MAX_KEY;
3393 spin_lock(&above->cst.spin);
3396 if (++loops == 100000) {
3397 panic("indkey_freemap shit %p %p:%d\n",
3398 parent, base, count);
3400 chain = hammer2_combined_find(parent, base, count,
3401 &cache_index, &key_next,
3402 key_beg, key_end, &bref);
3409 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3410 if (key_next == 0 || key_next > key_end)
3417 * Use the full live (not deleted) element for the scan
3418 * iteration. HAMMER2 does not allow partial replacements.
3420 * XXX should be built into hammer2_combined_find().
3422 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3424 if (keybits > bref->keybits) {
3426 keybits = bref->keybits;
3427 } else if (keybits == bref->keybits && bref->key < key) {
3434 spin_unlock(&above->cst.spin);
3437 * Return the keybits for a higher-level FREEMAP_NODE covering
3441 case HAMMER2_FREEMAP_LEVEL0_RADIX:
3442 keybits = HAMMER2_FREEMAP_LEVEL1_RADIX;
3444 case HAMMER2_FREEMAP_LEVEL1_RADIX:
3445 keybits = HAMMER2_FREEMAP_LEVEL2_RADIX;
3447 case HAMMER2_FREEMAP_LEVEL2_RADIX:
3448 keybits = HAMMER2_FREEMAP_LEVEL3_RADIX;
3450 case HAMMER2_FREEMAP_LEVEL3_RADIX:
3451 keybits = HAMMER2_FREEMAP_LEVEL4_RADIX;
3453 case HAMMER2_FREEMAP_LEVEL4_RADIX:
3454 panic("hammer2_chain_indkey_freemap: level too high");
3457 panic("hammer2_chain_indkey_freemap: bad radix");
3466 * Calculate the keybits and highside/lowside of the indirect block the
3467 * caller is creating.
3470 hammer2_chain_indkey_normal(hammer2_chain_t *parent, hammer2_key_t *keyp,
3471 int keybits, hammer2_blockref_t *base, int count)
3473 hammer2_chain_core_t *above;
3474 hammer2_blockref_t *bref;
3475 hammer2_chain_t *chain;
3476 hammer2_key_t key_beg;
3477 hammer2_key_t key_end;
3478 hammer2_key_t key_next;
3487 above = parent->core;
3492 * Calculate the range of keys in the array being careful to skip
3493 * slots which are overridden with a deletion. Once the scan
3494 * completes we will cut the key range in half and shift half the
3495 * range into the new indirect block.
3498 key_end = HAMMER2_MAX_KEY;
3500 spin_lock(&above->cst.spin);
3503 if (++loops == 100000) {
3504 panic("indkey_freemap shit %p %p:%d\n",
3505 parent, base, count);
3507 chain = hammer2_combined_find(parent, base, count,
3508 &cache_index, &key_next,
3509 key_beg, key_end, &bref);
3516 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3517 if (key_next == 0 || key_next > key_end)
3524 * Use the full live (not deleted) element for the scan
3525 * iteration. HAMMER2 does not allow partial replacements.
3527 * XXX should be built into hammer2_combined_find().
3529 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3532 * Expand our calculated key range (key, keybits) to fit
3533 * the scanned key. nkeybits represents the full range
3534 * that we will later cut in half (two halves @ nkeybits - 1).
3537 if (nkeybits < bref->keybits) {
3538 if (bref->keybits > 64) {
3539 kprintf("bad bref chain %p bref %p\n",
3543 nkeybits = bref->keybits;
3545 while (nkeybits < 64 &&
3546 (~(((hammer2_key_t)1 << nkeybits) - 1) &
3547 (key ^ bref->key)) != 0) {
3552 * If the new key range is larger we have to determine
3553 * which side of the new key range the existing keys fall
3554 * under by checking the high bit, then collapsing the
3555 * locount into the hicount or vise-versa.
3557 if (keybits != nkeybits) {
3558 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) {
3569 * The newly scanned key will be in the lower half or the
3570 * upper half of the (new) key range.
3572 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key)
3581 spin_unlock(&above->cst.spin);
3582 bref = NULL; /* now invalid (safety) */
3585 * Adjust keybits to represent half of the full range calculated
3586 * above (radix 63 max)
3591 * Select whichever half contains the most elements. Theoretically
3592 * we can select either side as long as it contains at least one
3593 * element (in order to ensure that a free slot is present to hold
3594 * the indirect block).
3596 if (hammer2_indirect_optimize) {
3598 * Insert node for least number of keys, this will arrange
3599 * the first few blocks of a large file or the first few
3600 * inodes in a directory with fewer indirect blocks when
3603 if (hicount < locount && hicount != 0)
3604 key |= (hammer2_key_t)1 << keybits;
3606 key &= ~(hammer2_key_t)1 << keybits;
3609 * Insert node for most number of keys, best for heavily
3612 if (hicount > locount)
3613 key |= (hammer2_key_t)1 << keybits;
3615 key &= ~(hammer2_key_t)1 << keybits;
3623 * Sets CHAIN_DELETED and CHAIN_MOVED in the chain being deleted and
3624 * set chain->delete_tid. The chain is not actually marked possibly-free
3625 * in the freemap until the deletion is completely flushed out (because
3626 * a flush which doesn't cover the entire deletion is flushing the deleted
3627 * chain as if it were live).
3629 * This function does NOT generate a modification to the parent. It
3630 * would be nearly impossible to figure out which parent to modify anyway.
3631 * Such modifications are handled top-down by the flush code and are
3632 * properly merged using the flush synchronization point.
3634 * The find/get code will properly overload the RBTREE check on top of
3635 * the bref check to detect deleted entries.
3637 * This function is NOT recursive. Any entity already pushed into the
3638 * chain (such as an inode) may still need visibility into its contents,
3639 * as well as the ability to read and modify the contents. For example,
3640 * for an unlinked file which is still open.
3642 * NOTE: This function does NOT set chain->modify_tid, allowing future
3643 * code to distinguish between live and deleted chains by testing
3644 * trans->sync_tid vs chain->modify_tid and chain->delete_tid.
3646 * NOTE: Deletions normally do not occur in the middle of a duplication
3647 * chain but we use a trick for hardlink migration that refactors
3648 * the originating inode without deleting it, so we make no assumptions
3652 hammer2_chain_delete(hammer2_trans_t *trans, hammer2_chain_t *chain, int flags)
3654 KKASSERT(ccms_thread_lock_owned(&chain->core->cst));
3657 * Nothing to do if already marked.
3659 if (chain->flags & HAMMER2_CHAIN_DELETED)
3663 * The setting of DELETED causes finds, lookups, and _next iterations
3664 * to no longer recognize the chain. RB_SCAN()s will still have
3665 * visibility (needed for flush serialization points).
3667 * We need the spinlock on the core whos RBTREE contains chain
3668 * to protect against races.
3670 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
3671 spin_lock(&chain->above->cst.spin);
3673 KKASSERT(trans->sync_tid >= chain->modify_tid);
3674 chain->delete_tid = trans->sync_tid;
3675 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3676 atomic_add_int(&chain->above->live_count, -1);
3677 ++chain->above->generation;
3680 * We must set MOVED along with DELETED for the flush code to
3681 * recognize the operation and properly disconnect the chain
3684 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
3685 hammer2_chain_ref(chain);
3686 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
3688 spin_unlock(&chain->above->cst.spin);
3690 if (flags & HAMMER2_DELETE_WILLDUP)
3691 atomic_set_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
3693 hammer2_chain_setsubmod(trans, chain);
3697 * Called with the core spinlock held to check for freeable layers.
3698 * Used by the flush code. Layers can wind up not being freed due
3699 * to the temporary layer->refs count. This function frees up any
3700 * layers that were missed.
3703 hammer2_chain_layer_check_locked(hammer2_mount_t *hmp,
3704 hammer2_chain_core_t *core)
3706 hammer2_chain_layer_t *layer;
3707 hammer2_chain_layer_t *tmp;
3709 tmp = TAILQ_FIRST(&core->layerq);
3710 while ((layer = tmp) != NULL) {
3711 tmp = TAILQ_NEXT(tmp, entry);
3712 if (layer->refs == 0 && RB_EMPTY(&layer->rbtree)) {
3713 TAILQ_REMOVE(&core->layerq, layer, entry);
3716 spin_unlock(&core->cst.spin);
3717 kfree(layer, hmp->mchain);
3718 spin_lock(&core->cst.spin);
3726 * Returns the index of the nearest element in the blockref array >= elm.
3727 * Returns (count) if no element could be found.
3729 * Sets *key_nextp to the next key for loop purposes but does not modify
3730 * it if the next key would be higher than the current value of *key_nextp.
3731 * Note that *key_nexp can overflow to 0, which should be tested by the
3734 * (*cache_indexp) is a heuristic and can be any value without effecting
3737 * The spin lock on the related chain must be held.
3740 hammer2_base_find(hammer2_chain_t *chain,
3741 hammer2_blockref_t *base, int count,
3742 int *cache_indexp, hammer2_key_t *key_nextp,
3743 hammer2_key_t key_beg, hammer2_key_t key_end)
3745 hammer2_chain_core_t *core = chain->core;
3746 hammer2_blockref_t *scan;
3747 hammer2_key_t scan_end;
3752 * Require the live chain's already have their core's counted
3753 * so we can optimize operations.
3755 KKASSERT((chain->flags & HAMMER2_CHAIN_DUPLICATED) ||
3756 core->flags & HAMMER2_CORE_COUNTEDBREFS);
3761 if (count == 0 || base == NULL)
3765 * Sequential optimization using *cache_indexp. This is the most
3768 * We can avoid trailing empty entries on live chains, otherwise
3769 * we might have to check the whole block array.
3773 if (chain->flags & HAMMER2_CHAIN_DUPLICATED)
3776 limit = core->live_zero;
3781 KKASSERT(i < count);
3787 while (i > 0 && (scan->type == 0 || scan->key > key_beg)) {
3794 * Search forwards, stop when we find a scan element which
3795 * encloses the key or until we know that there are no further
3799 if (scan->type != 0) {
3800 if (scan->key > key_beg)
3802 scan_end = scan->key +
3803 ((hammer2_key_t)1 << scan->keybits) - 1;
3804 if (scan_end >= key_beg)
3817 scan_end = scan->key +
3818 ((hammer2_key_t)1 << scan->keybits);
3819 if (scan_end && (*key_nextp > scan_end ||
3821 *key_nextp = scan_end;
3829 * Do a combined search and return the next match either from the blockref
3830 * array or from the in-memory chain. Sets *bresp to the returned bref in
3831 * both cases, or sets it to NULL if the search exhausted. Only returns
3832 * a non-NULL chain if the search matched from the in-memory chain.
3834 * Must be called with above's spinlock held. Spinlock remains held
3835 * through the operation.
3837 * The returned chain is not locked or referenced. Use the returned bref
3838 * to determine if the search exhausted or not.
3840 static hammer2_chain_t *
3841 hammer2_combined_find(hammer2_chain_t *parent,
3842 hammer2_blockref_t *base, int count,
3843 int *cache_indexp, hammer2_key_t *key_nextp,
3844 hammer2_key_t key_beg, hammer2_key_t key_end,
3845 hammer2_blockref_t **bresp)
3847 hammer2_blockref_t *bref;
3848 hammer2_chain_t *chain;
3851 *key_nextp = key_end + 1;
3852 i = hammer2_base_find(parent, base, count, cache_indexp,
3853 key_nextp, key_beg, key_end);
3854 chain = hammer2_chain_find(parent, key_nextp, key_beg, key_end);
3859 if (i == count && chain == NULL) {
3861 return(chain); /* NULL */
3865 * Only chain matched
3868 bref = &chain->bref;
3873 * Only blockref matched.
3875 if (chain == NULL) {
3881 * Both in-memory and blockref match.
3883 * If they are both flush with the left hand side select the chain.
3884 * If their starts match select the chain.
3885 * Otherwise the nearer element wins.
3887 if (chain->bref.key <= key_beg && base[i].key <= key_beg) {
3888 bref = &chain->bref;
3891 if (chain->bref.key <= base[i].key) {
3892 bref = &chain->bref;
3900 * If the bref is out of bounds we've exhausted our search.
3903 if (bref->key > key_end) {
3913 * Locate the specified block array element and delete it. The element
3916 * The spin lock on the related chain must be held.
3918 * NOTE: live_count was adjusted when the chain was deleted, so it does not
3919 * need to be adjusted when we commit the media change.
3922 hammer2_base_delete(hammer2_chain_t *parent,
3923 hammer2_blockref_t *base, int count,
3924 int *cache_indexp, hammer2_chain_t *child)
3926 hammer2_blockref_t *elm = &child->bref;
3927 hammer2_chain_core_t *core = parent->core;
3928 hammer2_key_t key_next;
3932 * Delete element. Expect the element to exist.
3934 * XXX see caller, flush code not yet sophisticated enough to prevent
3935 * re-flushed in some cases.
3937 key_next = 0; /* max range */
3938 i = hammer2_base_find(parent, base, count, cache_indexp,
3939 &key_next, elm->key, elm->key);
3940 if (i == count || base[i].type == 0 ||
3941 base[i].key != elm->key || base[i].keybits != elm->keybits) {
3942 panic("delete base %p element not found at %d/%d elm %p\n",
3943 base, i, count, elm);
3946 bzero(&base[i], sizeof(*base));
3949 * We can only optimize core->live_zero for live chains.
3951 if ((parent->flags & HAMMER2_CHAIN_DUPLICATED) == 0) {
3952 if (core->live_zero == i + 1) {
3953 while (--i >= 0 && base[i].type == 0)
3955 core->live_zero = i + 1;
3961 * Insert the specified element. The block array must not already have the
3962 * element and must have space available for the insertion.
3964 * The spin lock on the related chain must be held.
3966 * NOTE: live_count was adjusted when the chain was deleted, so it does not
3967 * need to be adjusted when we commit the media change.
3970 hammer2_base_insert(hammer2_chain_t *parent,
3971 hammer2_blockref_t *base, int count,
3972 int *cache_indexp, hammer2_chain_t *child)
3974 hammer2_blockref_t *elm = &child->bref;
3975 hammer2_chain_core_t *core = parent->core;
3976 hammer2_key_t key_next;
3985 * Insert new element. Expect the element to not already exist
3986 * unless we are replacing it.
3988 * XXX see caller, flush code not yet sophisticated enough to prevent
3989 * re-flushed in some cases.
3991 key_next = 0; /* max range */
3992 i = hammer2_base_find(parent, base, count, cache_indexp,
3993 &key_next, elm->key, elm->key);
3996 * Shortcut fill optimization, typical ordered insertion(s) may not
3999 KKASSERT(i >= 0 && i <= count);
4002 * We can only optimize core->live_zero for live chains.
4004 if (i == count && core->live_zero < count) {
4005 if ((parent->flags & HAMMER2_CHAIN_DUPLICATED) == 0) {
4006 i = core->live_zero++;
4012 xkey = elm->key + ((hammer2_key_t)1 << elm->keybits) - 1;
4013 if (i != count && (base[i].key < elm->key || xkey >= base[i].key)) {
4014 panic("insert base %p overlapping elements at %d elm %p\n",
4019 * Try to find an empty slot before or after.
4023 while (j > 0 || k < count) {
4025 if (j >= 0 && base[j].type == 0) {
4029 bcopy(&base[j+1], &base[j],
4030 (i - j - 1) * sizeof(*base));
4036 if (k < count && base[k].type == 0) {
4037 bcopy(&base[i], &base[i+1],
4038 (k - i) * sizeof(hammer2_blockref_t));
4042 * We can only update core->live_zero for live
4045 if ((parent->flags & HAMMER2_CHAIN_DUPLICATED) == 0) {
4046 if (core->live_zero <= k)
4047 core->live_zero = k + 1;
4053 panic("hammer2_base_insert: no room!");
4060 for (l = 0; l < count; ++l) {
4062 key_next = base[l].key +
4063 ((hammer2_key_t)1 << base[l].keybits) - 1;
4067 while (++l < count) {
4069 if (base[l].key <= key_next)
4070 panic("base_insert %d %d,%d,%d fail %p:%d", u, i, j, k, base, l);
4071 key_next = base[l].key +
4072 ((hammer2_key_t)1 << base[l].keybits) - 1;
4082 * Sort the blockref array for the chain. Used by the flush code to
4083 * sort the blockref[] array.
4085 * The chain must be exclusively locked AND spin-locked.
4087 typedef hammer2_blockref_t *hammer2_blockref_p;
4091 hammer2_base_sort_callback(const void *v1, const void *v2)
4093 hammer2_blockref_p bref1 = *(const hammer2_blockref_p *)v1;
4094 hammer2_blockref_p bref2 = *(const hammer2_blockref_p *)v2;
4097 * Make sure empty elements are placed at the end of the array
4099 if (bref1->type == 0) {
4100 if (bref2->type == 0)
4103 } else if (bref2->type == 0) {
4110 if (bref1->key < bref2->key)
4112 if (bref1->key > bref2->key)
4118 hammer2_base_sort(hammer2_chain_t *chain)
4120 hammer2_blockref_t *base;
4123 switch(chain->bref.type) {
4124 case HAMMER2_BREF_TYPE_INODE:
4126 * Special shortcut for embedded data returns the inode
4127 * itself. Callers must detect this condition and access
4128 * the embedded data (the strategy code does this for us).
4130 * This is only applicable to regular files and softlinks.
4132 if (chain->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA)
4134 base = &chain->data->ipdata.u.blockset.blockref[0];
4135 count = HAMMER2_SET_COUNT;
4137 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4138 case HAMMER2_BREF_TYPE_INDIRECT:
4140 * Optimize indirect blocks in the INITIAL state to avoid
4143 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) == 0);
4144 base = &chain->data->npdata[0];
4145 count = chain->bytes / sizeof(hammer2_blockref_t);
4147 case HAMMER2_BREF_TYPE_VOLUME:
4148 base = &chain->hmp->voldata.sroot_blockset.blockref[0];
4149 count = HAMMER2_SET_COUNT;
4151 case HAMMER2_BREF_TYPE_FREEMAP:
4152 base = &chain->hmp->voldata.freemap_blockset.blockref[0];
4153 count = HAMMER2_SET_COUNT;
4156 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
4158 base = NULL; /* safety */
4159 count = 0; /* safety */
4161 kqsort(base, count, sizeof(*base), hammer2_base_sort_callback);
4167 * Chain memory management
4170 hammer2_chain_wait(hammer2_chain_t *chain)
4172 tsleep(chain, 0, "chnflw", 1);
4176 * Manage excessive memory resource use for chain and related
4180 hammer2_chain_memory_wait(hammer2_pfsmount_t *pmp)
4183 while (pmp->inmem_chains > desiredvnodes / 10 &&
4184 pmp->inmem_chains > pmp->mp->mnt_nvnodelistsize * 2) {
4186 speedup_syncer(pmp->mp);
4187 pmp->inmem_waiting = 1;
4188 tsleep(&pmp->inmem_waiting, 0, "chnmem", hz);
4192 if (pmp->inmem_chains > desiredvnodes / 10 &&
4193 pmp->inmem_chains > pmp->mp->mnt_nvnodelistsize * 7 / 4) {
4194 speedup_syncer(pmp->mp);
4200 hammer2_chain_memory_wakeup(hammer2_pfsmount_t *pmp)
4202 if (pmp->inmem_waiting &&
4203 (pmp->inmem_chains <= desiredvnodes / 10 ||
4204 pmp->inmem_chains <= pmp->mp->mnt_nvnodelistsize * 2)) {
4206 pmp->inmem_waiting = 0;
4207 wakeup(&pmp->inmem_waiting);
4213 adjreadcounter(hammer2_blockref_t *bref, size_t bytes)
4217 switch(bref->type) {
4218 case HAMMER2_BREF_TYPE_DATA:
4219 counterp = &hammer2_iod_file_read;
4221 case HAMMER2_BREF_TYPE_INODE:
4222 counterp = &hammer2_iod_meta_read;
4224 case HAMMER2_BREF_TYPE_INDIRECT:
4225 counterp = &hammer2_iod_indr_read;
4227 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4228 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
4229 counterp = &hammer2_iod_fmap_read;
4232 counterp = &hammer2_iod_volu_read;