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) {
395 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
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);
409 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
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);
447 chain->inlayer = layer;
448 ++above->chain_count;
451 if ((flags & HAMMER2_CHAIN_INSERT_LIVE) &&
452 (chain->flags & HAMMER2_CHAIN_DELETED) == 0) {
453 atomic_add_int(&above->live_count, 1);
455 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
457 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
458 spin_unlock(&above->cst.spin);
462 * Drop the caller's reference to the chain. When the ref count drops to
463 * zero this function will disassociate the chain from its parent and
464 * deallocate it, then recursely drop the parent using the implied ref
465 * from the chain's chain->parent.
467 * WARNING! Just because we are able to deallocate a chain doesn't mean
468 * that chain->core->rbtree is empty. There can still be a sharecnt
469 * on chain->core and RBTREE entries that refer to different parents.
471 static hammer2_chain_t *hammer2_chain_lastdrop(hammer2_chain_t *chain,
472 struct h2_core_list *delayq);
475 hammer2_chain_drop(hammer2_chain_t *chain)
477 struct h2_core_list delayq;
478 hammer2_chain_t *scan;
482 if (hammer2_debug & 0x200000)
485 if (chain->flags & HAMMER2_CHAIN_MOVED)
487 if (chain->flags & HAMMER2_CHAIN_MODIFIED)
489 KKASSERT(chain->refs > need);
499 chain = hammer2_chain_lastdrop(chain, &delayq);
501 if (atomic_cmpset_int(&chain->refs, refs, refs - 1))
503 /* retry the same chain */
507 * When we've exhausted lastdrop chaining pull off of delayq.
508 * chains on delayq are dead but are used to placehold other
509 * chains which we added a ref to for the purpose of dropping.
512 hammer2_mount_t *hmp;
514 if ((scan = TAILQ_FIRST(&delayq)) != NULL) {
515 chain = (void *)scan->data;
516 TAILQ_REMOVE(&delayq, scan, core_entry);
517 scan->flags &= ~HAMMER2_CHAIN_ALLOCATED;
520 kfree(scan, hmp->mchain);
527 * Safe handling of the 1->0 transition on chain. Returns a chain for
528 * recursive drop or NULL, possibly returning the same chain if the atomic
531 * Whem two chains need to be recursively dropped we use the chain
532 * we would otherwise free to placehold the additional chain. It's a bit
533 * convoluted but we can't just recurse without potentially blowing out
536 * The cst spinlock is allowed nest child-to-parent (not parent-to-child).
540 hammer2_chain_lastdrop(hammer2_chain_t *chain, struct h2_core_list *delayq)
542 hammer2_pfsmount_t *pmp;
543 hammer2_mount_t *hmp;
544 hammer2_chain_core_t *above;
545 hammer2_chain_core_t *core;
546 hammer2_chain_layer_t *layer;
547 hammer2_chain_t *rdrop1;
548 hammer2_chain_t *rdrop2;
551 * Spinlock the core and check to see if it is empty. If it is
552 * not empty we leave chain intact with refs == 0. The elements
553 * in core->rbtree are associated with other chains contemporary
554 * with ours but not with our chain directly.
556 if ((core = chain->core) != NULL) {
557 spin_lock(&core->cst.spin);
560 * We can't free chains with children because there might
561 * be a flush dependency.
563 * NOTE: We return (chain) on failure to retry.
565 if (core->chain_count) {
566 if (atomic_cmpset_int(&chain->refs, 1, 0))
567 chain = NULL; /* success */
568 spin_unlock(&core->cst.spin);
571 /* no chains left under us */
574 * Because various parts of the code, including the inode
575 * structure, might be holding a stale chain and need to
576 * iterate to a non-stale sibling, we cannot remove siblings
577 * unless they are at the head of chain.
579 * We can't free a live chain unless it is a the head
580 * of its ownerq. If we were to then the go-to chain
581 * would revert to the prior deleted chain.
583 if (TAILQ_FIRST(&core->ownerq) != chain) {
584 if (atomic_cmpset_int(&chain->refs, 1, 0))
585 chain = NULL; /* success */
586 spin_unlock(&core->cst.spin);
592 * chain->core has no children left so no accessors can get to our
593 * chain from there. Now we have to lock the above core to interlock
594 * remaining possible accessors that might bump chain's refs before
595 * we can safely drop chain's refs with intent to free the chain.
598 pmp = chain->pmp; /* can be NULL */
604 * Spinlock the parent and try to drop the last ref on chain.
605 * On success remove chain from its parent, otherwise return NULL.
607 * (normal core locks are top-down recursive but we define core
608 * spinlocks as bottom-up recursive, so this is safe).
610 if ((above = chain->above) != NULL) {
611 spin_lock(&above->cst.spin);
612 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) {
613 /* 1->0 transition failed */
614 spin_unlock(&above->cst.spin);
616 spin_unlock(&core->cst.spin);
617 return(chain); /* retry */
621 * 1->0 transition successful, remove chain from its
622 * above core. Track layer for removal/freeing.
624 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
625 layer = chain->inlayer;
626 RB_REMOVE(hammer2_chain_tree, &layer->rbtree, chain);
627 --above->chain_count;
628 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
630 chain->inlayer = NULL;
632 if (RB_EMPTY(&layer->rbtree) && layer->refs == 0) {
633 TAILQ_REMOVE(&above->layerq, layer, entry);
639 * If our chain was the last chain in the parent's core the
640 * core is now empty and its parents might now be droppable.
641 * Try to drop the first multi-homed parent by gaining a
642 * ref on it here and then dropping it below.
644 if (above->chain_count == 0) {
645 rdrop1 = TAILQ_FIRST(&above->ownerq);
647 atomic_cmpset_int(&rdrop1->refs, 0, 1) == 0) {
651 spin_unlock(&above->cst.spin);
652 above = NULL; /* safety */
656 * Successful 1->0 transition and the chain can be destroyed now.
658 * We still have the core spinlock (if core is non-NULL), and core's
659 * chain_count is 0. The above spinlock is gone.
661 * Remove chain from ownerq. Once core has no more owners (and no
662 * children which is already the case) we can destroy core.
664 * If core has more owners we may be able to continue a bottom-up
665 * drop with our next sibling.
670 TAILQ_REMOVE(&core->ownerq, chain, core_entry);
671 rdrop2 = TAILQ_FIRST(&core->ownerq);
672 if (rdrop2 && atomic_cmpset_int(&rdrop2->refs, 0, 1) == 0)
674 spin_unlock(&core->cst.spin);
677 * We can do the final 1->0 transition with an atomic op
678 * after releasing core's spinlock.
680 if (atomic_fetchadd_int(&core->sharecnt, -1) == 1) {
682 * On the 1->0 transition of core we can destroy
683 * it. Any remaining layers should no longer be
684 * referenced or visibile to other threads.
686 KKASSERT(TAILQ_EMPTY(&core->ownerq));
688 layer->good = 0xEF00;
689 kfree(layer, hmp->mchain);
691 while ((layer = TAILQ_FIRST(&core->layerq)) != NULL) {
692 KKASSERT(layer->refs == 0 &&
693 RB_EMPTY(&layer->rbtree));
694 TAILQ_REMOVE(&core->layerq, layer, entry);
695 layer->good = 0xEF01;
696 kfree(layer, hmp->mchain);
699 KKASSERT(core->cst.count == 0);
700 KKASSERT(core->cst.upgrade == 0);
702 kfree(core, hmp->mchain);
704 core = NULL; /* safety */
708 * All spin locks are gone, finish freeing stuff.
710 KKASSERT((chain->flags & (HAMMER2_CHAIN_MOVED |
711 HAMMER2_CHAIN_MODIFIED)) == 0);
712 hammer2_chain_drop_data(chain, 1);
714 KKASSERT(chain->dio == NULL);
717 * Free saved empty layer and return chained drop.
720 layer->good = 0xEF02;
721 kfree(layer, hmp->mchain);
725 * Once chain resources are gone we can use the now dead chain
726 * structure to placehold what might otherwise require a recursive
727 * drop, because we have potentially two things to drop and can only
728 * return one directly.
730 if (rdrop1 && rdrop2) {
731 KKASSERT(chain->flags & HAMMER2_CHAIN_ALLOCATED);
732 chain->data = (void *)rdrop1;
733 TAILQ_INSERT_TAIL(delayq, chain, core_entry);
735 } else if (chain->flags & HAMMER2_CHAIN_ALLOCATED) {
736 chain->flags &= ~HAMMER2_CHAIN_ALLOCATED;
738 kfree(chain, hmp->mchain);
741 atomic_add_long(&pmp->inmem_chains, -1);
742 hammer2_chain_memory_wakeup(pmp);
746 * Either or both can be NULL. We already handled the case where
747 * both might not have been NULL.
756 * On either last lock release or last drop
759 hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop)
761 hammer2_mount_t *hmp = chain->hmp;
763 switch(chain->bref.type) {
764 case HAMMER2_BREF_TYPE_VOLUME:
765 case HAMMER2_BREF_TYPE_FREEMAP:
769 case HAMMER2_BREF_TYPE_INODE:
771 kfree(chain->data, hmp->mchain);
775 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
777 kfree(chain->data, hmp->mchain);
782 KKASSERT(chain->data == NULL);
788 * Ref and lock a chain element, acquiring its data with I/O if necessary,
789 * and specify how you would like the data to be resolved.
791 * Returns 0 on success or an error code if the data could not be acquired.
792 * The chain element is locked on return regardless of whether an error
795 * The lock is allowed to recurse, multiple locking ops will aggregate
796 * the requested resolve types. Once data is assigned it will not be
797 * removed until the last unlock.
799 * HAMMER2_RESOLVE_NEVER - Do not resolve the data element.
800 * (typically used to avoid device/logical buffer
803 * HAMMER2_RESOLVE_MAYBE - Do not resolve data elements for chains in
804 * the INITIAL-create state (indirect blocks only).
806 * Do not resolve data elements for DATA chains.
807 * (typically used to avoid device/logical buffer
810 * HAMMER2_RESOLVE_ALWAYS- Always resolve the data element.
812 * HAMMER2_RESOLVE_SHARED- (flag) The chain is locked shared, otherwise
813 * it will be locked exclusive.
815 * NOTE: Embedded elements (volume header, inodes) are always resolved
818 * NOTE: Specifying HAMMER2_RESOLVE_ALWAYS on a newly-created non-embedded
819 * element will instantiate and zero its buffer, and flush it on
822 * NOTE: (data) elements are normally locked RESOLVE_NEVER or RESOLVE_MAYBE
823 * so as not to instantiate a device buffer, which could alias against
824 * a logical file buffer. However, if ALWAYS is specified the
825 * device buffer will be instantiated anyway.
827 * WARNING! If data must be fetched a shared lock will temporarily be
828 * upgraded to exclusive. However, a deadlock can occur if
829 * the caller owns more than one shared lock.
832 hammer2_chain_lock(hammer2_chain_t *chain, int how)
834 hammer2_mount_t *hmp;
835 hammer2_chain_core_t *core;
836 hammer2_blockref_t *bref;
842 * Ref and lock the element. Recursive locks are allowed.
844 if ((how & HAMMER2_RESOLVE_NOREF) == 0)
845 hammer2_chain_ref(chain);
846 atomic_add_int(&chain->lockcnt, 1);
849 KKASSERT(hmp != NULL);
852 * Get the appropriate lock.
855 if (how & HAMMER2_RESOLVE_SHARED)
856 ccms_thread_lock(&core->cst, CCMS_STATE_SHARED);
858 ccms_thread_lock(&core->cst, CCMS_STATE_EXCLUSIVE);
861 * If we already have a valid data pointer no further action is
868 * Do we have to resolve the data?
870 switch(how & HAMMER2_RESOLVE_MASK) {
871 case HAMMER2_RESOLVE_NEVER:
873 case HAMMER2_RESOLVE_MAYBE:
874 if (chain->flags & HAMMER2_CHAIN_INITIAL)
876 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA)
879 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE)
882 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF)
885 case HAMMER2_RESOLVE_ALWAYS:
890 * Upgrade to an exclusive lock so we can safely manipulate the
891 * buffer cache. If another thread got to it before us we
894 ostate = ccms_thread_lock_upgrade(&core->cst);
896 ccms_thread_lock_downgrade(&core->cst, ostate);
901 * We must resolve to a device buffer, either by issuing I/O or
902 * by creating a zero-fill element. We do not mark the buffer
903 * dirty when creating a zero-fill element (the hammer2_chain_modify()
904 * API must still be used to do that).
906 * The device buffer is variable-sized in powers of 2 down
907 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
908 * chunk always contains buffers of the same size. (XXX)
910 * The minimum physical IO size may be larger than the variable
916 * The getblk() optimization can only be used on newly created
917 * elements if the physical block size matches the request.
919 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
920 error = hammer2_io_new(hmp, bref->data_off, chain->bytes,
923 error = hammer2_io_bread(hmp, bref->data_off, chain->bytes,
925 adjreadcounter(&chain->bref, chain->bytes);
929 kprintf("hammer2_chain_lock: I/O error %016jx: %d\n",
930 (intmax_t)bref->data_off, error);
931 hammer2_io_bqrelse(&chain->dio);
932 ccms_thread_lock_downgrade(&core->cst, ostate);
937 * We can clear the INITIAL state now, we've resolved the buffer
938 * to zeros and marked it dirty with hammer2_io_new().
940 bdata = hammer2_io_data(chain->dio, chain->bref.data_off);
941 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
942 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
946 * Setup the data pointer, either pointing it to an embedded data
947 * structure and copying the data from the buffer, or pointing it
950 * The buffer is not retained when copying to an embedded data
951 * structure in order to avoid potential deadlocks or recursions
952 * on the same physical buffer.
954 switch (bref->type) {
955 case HAMMER2_BREF_TYPE_VOLUME:
956 case HAMMER2_BREF_TYPE_FREEMAP:
958 * Copy data from bp to embedded buffer
960 panic("hammer2_chain_lock: called on unresolved volume header");
962 case HAMMER2_BREF_TYPE_INODE:
964 * Copy data from dio to embedded buffer, do not retain the
967 KKASSERT(chain->bytes == sizeof(chain->data->ipdata));
968 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
969 chain->data = kmalloc(sizeof(chain->data->ipdata),
970 hmp->mchain, M_WAITOK | M_ZERO);
971 bcopy(bdata, &chain->data->ipdata, chain->bytes);
972 hammer2_io_bqrelse(&chain->dio);
974 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
975 KKASSERT(chain->bytes == sizeof(chain->data->bmdata));
976 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
977 chain->data = kmalloc(sizeof(chain->data->bmdata),
978 hmp->mchain, M_WAITOK | M_ZERO);
979 bcopy(bdata, &chain->data->bmdata, chain->bytes);
980 hammer2_io_bqrelse(&chain->dio);
982 case HAMMER2_BREF_TYPE_INDIRECT:
983 case HAMMER2_BREF_TYPE_DATA:
984 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
987 * Point data at the device buffer and leave bp intact.
989 chain->data = (void *)bdata;
992 ccms_thread_lock_downgrade(&core->cst, ostate);
997 * This basically calls hammer2_io_breadcb() but does some pre-processing
998 * of the chain first to handle certain cases.
1001 hammer2_chain_load_async(hammer2_chain_t *chain,
1002 void (*callback)(hammer2_io_t *dio,
1003 hammer2_chain_t *chain,
1004 void *arg_p, off_t arg_o),
1005 void *arg_p, off_t arg_o)
1007 hammer2_mount_t *hmp;
1008 struct hammer2_io *dio;
1009 hammer2_blockref_t *bref;
1013 callback(NULL, chain, arg_p, arg_o);
1018 * We must resolve to a device buffer, either by issuing I/O or
1019 * by creating a zero-fill element. We do not mark the buffer
1020 * dirty when creating a zero-fill element (the hammer2_chain_modify()
1021 * API must still be used to do that).
1023 * The device buffer is variable-sized in powers of 2 down
1024 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
1025 * chunk always contains buffers of the same size. (XXX)
1027 * The minimum physical IO size may be larger than the variable
1030 bref = &chain->bref;
1034 * The getblk() optimization can only be used on newly created
1035 * elements if the physical block size matches the request.
1037 if ((chain->flags & HAMMER2_CHAIN_INITIAL) &&
1038 chain->bytes == hammer2_devblksize(chain->bytes)) {
1039 error = hammer2_io_new(hmp, bref->data_off, chain->bytes, &dio);
1040 KKASSERT(error == 0);
1041 callback(dio, chain, arg_p, arg_o);
1046 * Otherwise issue a read
1048 adjreadcounter(&chain->bref, chain->bytes);
1049 hammer2_io_breadcb(hmp, bref->data_off, chain->bytes,
1050 callback, chain, arg_p, arg_o);
1054 * Unlock and deref a chain element.
1056 * On the last lock release any non-embedded data (chain->dio) will be
1060 hammer2_chain_unlock(hammer2_chain_t *chain)
1062 hammer2_chain_core_t *core = chain->core;
1063 ccms_state_t ostate;
1068 * The core->cst lock can be shared across several chains so we
1069 * need to track the per-chain lockcnt separately.
1071 * If multiple locks are present (or being attempted) on this
1072 * particular chain we can just unlock, drop refs, and return.
1074 * Otherwise fall-through on the 1->0 transition.
1077 lockcnt = chain->lockcnt;
1078 KKASSERT(lockcnt > 0);
1081 if (atomic_cmpset_int(&chain->lockcnt,
1082 lockcnt, lockcnt - 1)) {
1083 ccms_thread_unlock(&core->cst);
1084 hammer2_chain_drop(chain);
1088 if (atomic_cmpset_int(&chain->lockcnt, 1, 0))
1095 * On the 1->0 transition we upgrade the core lock (if necessary)
1096 * to exclusive for terminal processing. If after upgrading we find
1097 * that lockcnt is non-zero, another thread is racing us and will
1098 * handle the unload for us later on, so just cleanup and return
1099 * leaving the data/io intact
1101 * Otherwise if lockcnt is still 0 it is possible for it to become
1102 * non-zero and race, but since we hold the core->cst lock
1103 * exclusively all that will happen is that the chain will be
1104 * reloaded after we unload it.
1106 ostate = ccms_thread_lock_upgrade(&core->cst);
1107 if (chain->lockcnt) {
1108 ccms_thread_unlock_upgraded(&core->cst, ostate);
1109 hammer2_chain_drop(chain);
1114 * Shortcut the case if the data is embedded or not resolved.
1116 * Do NOT NULL out chain->data (e.g. inode data), it might be
1119 if (chain->dio == NULL) {
1120 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0)
1121 hammer2_chain_drop_data(chain, 0);
1122 ccms_thread_unlock_upgraded(&core->cst, ostate);
1123 hammer2_chain_drop(chain);
1130 if (hammer2_io_isdirty(chain->dio) == 0) {
1132 } else if (chain->flags & HAMMER2_CHAIN_IOFLUSH) {
1133 switch(chain->bref.type) {
1134 case HAMMER2_BREF_TYPE_DATA:
1135 counterp = &hammer2_ioa_file_write;
1137 case HAMMER2_BREF_TYPE_INODE:
1138 counterp = &hammer2_ioa_meta_write;
1140 case HAMMER2_BREF_TYPE_INDIRECT:
1141 counterp = &hammer2_ioa_indr_write;
1143 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1144 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1145 counterp = &hammer2_ioa_fmap_write;
1148 counterp = &hammer2_ioa_volu_write;
1151 *counterp += chain->bytes;
1153 switch(chain->bref.type) {
1154 case HAMMER2_BREF_TYPE_DATA:
1155 counterp = &hammer2_iod_file_write;
1157 case HAMMER2_BREF_TYPE_INODE:
1158 counterp = &hammer2_iod_meta_write;
1160 case HAMMER2_BREF_TYPE_INDIRECT:
1161 counterp = &hammer2_iod_indr_write;
1163 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1164 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1165 counterp = &hammer2_iod_fmap_write;
1168 counterp = &hammer2_iod_volu_write;
1171 *counterp += chain->bytes;
1175 * Clean out the dio.
1177 * If a device buffer was used for data be sure to destroy the
1178 * buffer when we are done to avoid aliases (XXX what about the
1179 * underlying VM pages?).
1181 * NOTE: Freemap leaf's use reserved blocks and thus no aliasing
1184 * NOTE: The isdirty check tracks whether we have to bdwrite() the
1185 * buffer or not. The buffer might already be dirty. The
1186 * flag is re-set when chain_modify() is called, even if
1187 * MODIFIED is already set, allowing the OS to retire the
1188 * buffer independent of a hammer2 flush.
1191 if ((chain->flags & HAMMER2_CHAIN_IOFLUSH) &&
1192 hammer2_io_isdirty(chain->dio)) {
1193 hammer2_io_bawrite(&chain->dio);
1195 hammer2_io_bqrelse(&chain->dio);
1197 ccms_thread_unlock_upgraded(&core->cst, ostate);
1198 hammer2_chain_drop(chain);
1202 * This counts the number of live blockrefs in a block array and
1203 * also calculates the point at which all remaining blockrefs are empty.
1205 * NOTE: Flag is not set until after the count is complete, allowing
1206 * callers to test the flag without holding the spinlock.
1208 * NOTE: If base is NULL the related chain is still in the INITIAL
1209 * state and there are no blockrefs to count.
1211 * NOTE: live_count may already have some counts accumulated due to
1212 * creation and deletion and could even be initially negative.
1215 hammer2_chain_countbrefs(hammer2_chain_t *chain,
1216 hammer2_blockref_t *base, int count)
1218 hammer2_chain_core_t *core = chain->core;
1220 spin_lock(&core->cst.spin);
1221 if ((core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0) {
1223 while (--count >= 0) {
1224 if (base[count].type)
1227 core->live_zero = count + 1;
1228 while (count >= 0) {
1229 if (base[count].type)
1230 atomic_add_int(&core->live_count, 1);
1234 core->live_zero = 0;
1236 /* else do not modify live_count */
1237 atomic_set_int(&core->flags, HAMMER2_CORE_COUNTEDBREFS);
1239 spin_unlock(&core->cst.spin);
1243 * Resize the chain's physical storage allocation in-place. This may
1244 * replace the passed-in chain with a new chain.
1246 * Chains can be resized smaller without reallocating the storage.
1247 * Resizing larger will reallocate the storage.
1249 * Must be passed an exclusively locked parent and chain, returns a new
1250 * exclusively locked chain at the same index and unlocks the old chain.
1251 * Flushes the buffer if necessary.
1253 * This function is mostly used with DATA blocks locked RESOLVE_NEVER in order
1254 * to avoid instantiating a device buffer that conflicts with the vnode
1255 * data buffer. That is, the passed-in bp is a logical buffer, whereas
1256 * any chain-oriented bp would be a device buffer.
1258 * XXX return error if cannot resize.
1261 hammer2_chain_resize(hammer2_trans_t *trans, hammer2_inode_t *ip,
1262 hammer2_chain_t *parent, hammer2_chain_t **chainp,
1263 int nradix, int flags)
1265 hammer2_mount_t *hmp;
1266 hammer2_chain_t *chain;
1274 * Only data and indirect blocks can be resized for now.
1275 * (The volu root, inodes, and freemap elements use a fixed size).
1277 KKASSERT(chain != &hmp->vchain);
1278 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA ||
1279 chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT);
1282 * Nothing to do if the element is already the proper size
1284 obytes = chain->bytes;
1285 nbytes = 1U << nradix;
1286 if (obytes == nbytes)
1290 * Delete the old chain and duplicate it at the same (parent, index),
1291 * returning a new chain. This allows the old chain to still be
1292 * used by the flush code. The new chain will be returned in a
1295 * The parent does not have to be locked for the delete/duplicate call,
1296 * but is in this particular code path.
1298 * NOTE: If we are not crossing a synchronization point the
1299 * duplication code will simply reuse the existing chain
1302 hammer2_chain_delete_duplicate(trans, &chain, 0);
1305 * Relocate the block, even if making it smaller (because different
1306 * block sizes may be in different regions).
1308 hammer2_freemap_alloc(trans, chain->hmp, &chain->bref, nbytes);
1309 chain->bytes = nbytes;
1310 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
1311 /*ip->delta_dcount += (ssize_t)(nbytes - obytes);*/ /* XXX atomic */
1314 * For now just support it on DATA chains (and not on indirect
1317 KKASSERT(chain->dio == NULL);
1321 * Make sure the chain is marked MOVED and propagate the update
1322 * to the root for flush.
1324 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
1325 hammer2_chain_ref(chain);
1326 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
1328 hammer2_chain_setsubmod(trans, chain);
1334 * Set a chain modified, making it read-write and duplicating it if necessary.
1335 * This function will assign a new physical block to the chain if necessary
1337 * Duplication of already-modified chains is possible when the modification
1338 * crosses a flush synchronization boundary.
1340 * Non-data blocks - The chain should be locked to at least the RESOLVE_MAYBE
1341 * level or the COW operation will not work.
1343 * Data blocks - The chain is usually locked RESOLVE_NEVER so as not to
1344 * run the data through the device buffers.
1346 * This function may return a different chain than was passed, in which case
1347 * the old chain will be unlocked and the new chain will be locked.
1349 * ip->chain may be adjusted by hammer2_chain_modify_ip().
1351 hammer2_inode_data_t *
1352 hammer2_chain_modify_ip(hammer2_trans_t *trans, hammer2_inode_t *ip,
1353 hammer2_chain_t **chainp, int flags)
1355 atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
1356 hammer2_chain_modify(trans, chainp, flags);
1357 if (ip->chain != *chainp)
1358 hammer2_inode_repoint(ip, NULL, *chainp);
1360 vsetisdirty(ip->vp);
1361 return(&ip->chain->data->ipdata);
1365 hammer2_chain_modify(hammer2_trans_t *trans, hammer2_chain_t **chainp,
1368 hammer2_mount_t *hmp;
1369 hammer2_chain_t *chain;
1379 kprintf("MODIFY %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1382 * Data must be resolved if already assigned unless explicitly
1383 * flagged otherwise.
1385 if (chain->data == NULL && (flags & HAMMER2_MODIFY_OPTDATA) == 0 &&
1386 (chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX)) {
1387 hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
1388 hammer2_chain_unlock(chain);
1392 * data is not optional for freemap chains (we must always be sure
1393 * to copy the data on COW storage allocations).
1395 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
1396 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
1397 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) ||
1398 (flags & HAMMER2_MODIFY_OPTDATA) == 0);
1402 * Determine if a delete-duplicate is needed.
1404 * (a) Modify_tid is part of a prior flush
1405 * (b) Transaction is concurrent with a flush (has higher tid)
1406 * (c) and chain is not in the initial state (freshly created)
1407 * (d) and caller didn't request an in-place modification.
1409 * The freemap and volume header special chains are never D-Dd.
1411 if (chain->modify_tid != trans->sync_tid && /* cross boundary */
1412 (flags & HAMMER2_MODIFY_INPLACE) == 0) { /* from d-d */
1413 if (chain != &hmp->fchain && chain != &hmp->vchain) {
1414 KKASSERT((flags & HAMMER2_MODIFY_ASSERTNOCOPY) == 0);
1415 hammer2_chain_delete_duplicate(trans, chainp, 0);
1417 kprintf("RET1A %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1421 kprintf("RET1B %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1425 /* fall through if fchain or vchain */
1429 * Otherwise do initial-chain handling
1431 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) {
1432 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
1433 hammer2_chain_ref(chain);
1437 * The modification or re-modification requires an allocation and
1440 * We normally always allocate new storage here. If storage exists
1441 * and MODIFY_NOREALLOC is passed in, we do not allocate new storage.
1443 if (chain != &hmp->vchain && chain != &hmp->fchain) {
1444 if ((chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX) == 0 ||
1445 ((flags & HAMMER2_MODIFY_NOREALLOC) == 0 &&
1446 chain->modify_tid != trans->sync_tid)
1448 hammer2_freemap_alloc(trans, chain->hmp,
1449 &chain->bref, chain->bytes);
1450 /* XXX failed allocation */
1451 } else if (chain->flags & HAMMER2_CHAIN_FORCECOW) {
1452 hammer2_freemap_alloc(trans, chain->hmp,
1453 &chain->bref, chain->bytes);
1454 /* XXX failed allocation */
1456 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
1459 chain->modify_tid = trans->sync_tid;
1460 if ((flags & HAMMER2_MODIFY_NO_MODIFY_TID) == 0)
1461 chain->bref.modify_tid = trans->sync_tid;
1464 * Do not COW if OPTDATA is set. INITIAL flag remains unchanged.
1465 * (OPTDATA does not prevent [re]allocation of storage, only the
1466 * related copy-on-write op).
1468 if (flags & HAMMER2_MODIFY_OPTDATA)
1472 * Clearing the INITIAL flag (for indirect blocks) indicates that
1473 * we've processed the uninitialized storage allocation.
1475 * If this flag is already clear we are likely in a copy-on-write
1476 * situation but we have to be sure NOT to bzero the storage if
1477 * no data is present.
1479 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
1480 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1487 * Instantiate data buffer and possibly execute COW operation
1489 switch(chain->bref.type) {
1490 case HAMMER2_BREF_TYPE_VOLUME:
1491 case HAMMER2_BREF_TYPE_FREEMAP:
1492 case HAMMER2_BREF_TYPE_INODE:
1493 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1495 * The data is embedded, no copy-on-write operation is
1498 KKASSERT(chain->dio == NULL);
1500 case HAMMER2_BREF_TYPE_DATA:
1501 case HAMMER2_BREF_TYPE_INDIRECT:
1502 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1504 * Perform the copy-on-write operation
1506 KKASSERT(chain != &hmp->vchain && chain != &hmp->fchain);
1509 error = hammer2_io_new(hmp, chain->bref.data_off,
1510 chain->bytes, &dio);
1512 error = hammer2_io_bread(hmp, chain->bref.data_off,
1513 chain->bytes, &dio);
1515 adjreadcounter(&chain->bref, chain->bytes);
1516 KKASSERT(error == 0);
1518 bdata = hammer2_io_data(dio, chain->bref.data_off);
1521 * Copy or zero-fill on write depending on whether
1522 * chain->data exists or not and set the dirty state for
1523 * the new buffer. Retire the existing buffer.
1526 KKASSERT(chain->dio != NULL);
1527 if (chain->data != (void *)bdata) {
1528 bcopy(chain->data, bdata, chain->bytes);
1530 } else if (wasinitial == 0) {
1532 * We have a problem. We were asked to COW but
1533 * we don't have any data to COW with!
1535 panic("hammer2_chain_modify: having a COW %p\n",
1538 hammer2_io_brelse(&chain->dio);
1539 chain->data = (void *)bdata;
1541 hammer2_io_setdirty(dio); /* modified by bcopy above */
1544 panic("hammer2_chain_modify: illegal non-embedded type %d",
1551 kprintf("RET2 %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1553 hammer2_chain_setsubmod(trans, chain);
1557 * Mark the volume as having been modified. This short-cut version
1558 * does not have to lock the volume's chain, which allows the ioctl
1559 * code to make adjustments to connections without deadlocking. XXX
1561 * No ref is made on vchain when flagging it MODIFIED.
1564 hammer2_modify_volume(hammer2_mount_t *hmp)
1566 hammer2_voldata_lock(hmp);
1567 hammer2_voldata_unlock(hmp, 1);
1571 * This function returns the chain at the nearest key within the specified
1572 * range with the highest delete_tid. The core spinlock must be held on
1573 * call and the returned chain will be referenced but not locked.
1575 * The returned chain may or may not be in a deleted state. Note that
1576 * live chains have a delete_tid = MAX_TID.
1578 * This function will recurse through chain->rbtree as necessary and will
1579 * return a *key_nextp suitable for iteration. *key_nextp is only set if
1580 * the iteration value is less than the current value of *key_nextp.
1582 * The caller should use (*key_nextp) to calculate the actual range of
1583 * the returned element, which will be (key_beg to *key_nextp - 1), because
1584 * there might be another element which is superior to the returned element
1587 * (*key_nextp) can be passed as key_beg in an iteration only while non-NULL
1588 * chains continue to be returned. On EOF (*key_nextp) may overflow since
1589 * it will wind up being (key_end + 1).
1591 struct hammer2_chain_find_info {
1592 hammer2_chain_t *best;
1593 hammer2_key_t key_beg;
1594 hammer2_key_t key_end;
1595 hammer2_key_t key_next;
1598 static int hammer2_chain_find_cmp(hammer2_chain_t *child, void *data);
1599 static int hammer2_chain_find_callback(hammer2_chain_t *child, void *data);
1603 hammer2_chain_find(hammer2_chain_t *parent, hammer2_key_t *key_nextp,
1604 hammer2_key_t key_beg, hammer2_key_t key_end)
1606 struct hammer2_chain_find_info info;
1607 hammer2_chain_layer_t *layer;
1610 info.key_beg = key_beg;
1611 info.key_end = key_end;
1612 info.key_next = *key_nextp;
1614 KKASSERT(parent->core->good == 0x1234);
1615 TAILQ_FOREACH(layer, &parent->core->layerq, entry) {
1616 KKASSERT(layer->good == 0xABCD);
1617 RB_SCAN(hammer2_chain_tree, &layer->rbtree,
1618 hammer2_chain_find_cmp, hammer2_chain_find_callback,
1621 *key_nextp = info.key_next;
1623 kprintf("chain_find %p %016jx:%016jx next=%016jx\n",
1624 parent, key_beg, key_end, *key_nextp);
1632 hammer2_chain_find_cmp(hammer2_chain_t *child, void *data)
1634 struct hammer2_chain_find_info *info = data;
1635 hammer2_key_t child_beg;
1636 hammer2_key_t child_end;
1638 child_beg = child->bref.key;
1639 child_end = child_beg + ((hammer2_key_t)1 << child->bref.keybits) - 1;
1641 if (child_end < info->key_beg)
1643 if (child_beg > info->key_end)
1650 hammer2_chain_find_callback(hammer2_chain_t *child, void *data)
1652 struct hammer2_chain_find_info *info = data;
1653 hammer2_chain_t *best;
1654 hammer2_key_t child_end;
1658 * Skip deleted chains which have been flushed (MOVED no longer set),
1659 * causes caller to check blockref array.
1661 if ((child->flags & (HAMMER2_CHAIN_DELETED | HAMMER2_CHAIN_MOVED)) ==
1662 HAMMER2_CHAIN_DELETED) {
1671 if ((best = info->best) == NULL) {
1673 * No previous best. Assign best
1676 } else if (best->bref.key <= info->key_beg &&
1677 child->bref.key <= info->key_beg) {
1679 * If our current best is flush with key_beg and child is
1680 * also flush with key_beg choose based on delete_tid.
1682 * key_next will automatically be limited to the smaller of
1683 * the two end-points.
1685 if (child->delete_tid > best->delete_tid)
1687 } else if (child->bref.key < best->bref.key) {
1689 * Child has a nearer key and best is not flush with key_beg.
1690 * Truncate key_next to the old best key iff it had a better
1694 if (best->delete_tid >= child->delete_tid &&
1695 (info->key_next > best->bref.key || info->key_next == 0))
1696 info->key_next = best->bref.key;
1697 } else if (child->bref.key == best->bref.key) {
1699 * If our current best is flush with the child then choose
1700 * based on delete_tid.
1702 * key_next will automatically be limited to the smaller of
1703 * the two end-points.
1705 if (child->delete_tid > best->delete_tid)
1709 * Keep the current best but truncate key_next to the child's
1710 * base iff the child has a higher delete_tid.
1712 * key_next will also automatically be limited to the smaller
1713 * of the two end-points (probably not necessary for this case
1714 * but we do it anyway).
1716 if (child->delete_tid >= best->delete_tid &&
1717 (info->key_next > child->bref.key || info->key_next == 0))
1718 info->key_next = child->bref.key;
1722 * Always truncate key_next based on child's end-of-range.
1724 child_end = child->bref.key + ((hammer2_key_t)1 << child->bref.keybits);
1725 if (child_end && (info->key_next > child_end || info->key_next == 0))
1726 info->key_next = child_end;
1732 * Retrieve the specified chain from a media blockref, creating the
1733 * in-memory chain structure which reflects it. modify_tid will be
1734 * left 0 which forces any modifications to issue a delete-duplicate.
1736 * NULL is returned if the insertion races.
1738 * Caller must hold the parent locked shared or exclusive since we may
1739 * need the parent's bref array to find our block.
1742 hammer2_chain_get(hammer2_chain_t *parent, hammer2_blockref_t *bref)
1744 hammer2_mount_t *hmp = parent->hmp;
1745 hammer2_chain_core_t *above = parent->core;
1746 hammer2_chain_t *chain;
1749 * Allocate a chain structure representing the existing media
1750 * entry. Resulting chain has one ref and is not locked.
1752 chain = hammer2_chain_alloc(hmp, parent->pmp, NULL, bref);
1753 hammer2_chain_core_alloc(NULL, chain, NULL);
1754 /* ref'd chain returned */
1755 chain->modify_tid = chain->bref.mirror_tid;
1758 * Link the chain into its parent. A spinlock is required to safely
1759 * access the RBTREE, and it is possible to collide with another
1760 * hammer2_chain_get() operation because the caller might only hold
1761 * a shared lock on the parent.
1763 KKASSERT(parent->refs > 0);
1764 hammer2_chain_insert(above, NULL, chain,
1765 HAMMER2_CHAIN_INSERT_SPIN |
1766 HAMMER2_CHAIN_INSERT_RACE);
1767 if ((chain->flags & HAMMER2_CHAIN_ONRBTREE) == 0) {
1768 kprintf("chain %p not on RBTREE\n", chain);
1769 hammer2_chain_drop(chain);
1774 * Return our new chain referenced but not locked.
1780 * Lookup initialization/completion API
1783 hammer2_chain_lookup_init(hammer2_chain_t *parent, int flags)
1785 if (flags & HAMMER2_LOOKUP_SHARED) {
1786 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS |
1787 HAMMER2_RESOLVE_SHARED);
1789 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
1795 hammer2_chain_lookup_done(hammer2_chain_t *parent)
1798 hammer2_chain_unlock(parent);
1803 hammer2_chain_getparent(hammer2_chain_t **parentp, int how)
1805 hammer2_chain_t *oparent;
1806 hammer2_chain_t *bparent;
1807 hammer2_chain_t *nparent;
1808 hammer2_chain_core_t *above;
1811 above = oparent->above;
1813 spin_lock(&above->cst.spin);
1814 bparent = TAILQ_FIRST(&above->ownerq);
1815 hammer2_chain_ref(bparent);
1819 while (nparent->flags & HAMMER2_CHAIN_DUPLICATED)
1820 nparent = TAILQ_NEXT(nparent, core_entry);
1821 hammer2_chain_ref(nparent);
1822 spin_unlock(&above->cst.spin);
1825 * Be careful of order
1827 hammer2_chain_unlock(oparent);
1828 hammer2_chain_lock(nparent, how | HAMMER2_RESOLVE_NOREF);
1829 hammer2_chain_drop(bparent);
1832 * We might have raced a delete-duplicate.
1834 if (nparent->flags & HAMMER2_CHAIN_DUPLICATED) {
1835 spin_lock(&above->cst.spin);
1836 if (nparent->flags & HAMMER2_CHAIN_DUPLICATED) {
1837 spin_unlock(&above->cst.spin);
1838 hammer2_chain_ref(nparent);
1839 hammer2_chain_unlock(nparent);
1841 spin_lock(&above->cst.spin);
1842 continue; /* retry */
1844 spin_unlock(&above->cst.spin);
1854 * Locate the first chain whos key range overlaps (key_beg, key_end) inclusive.
1855 * (*parentp) typically points to an inode but can also point to a related
1856 * indirect block and this function will recurse upwards and find the inode
1859 * (*parentp) must be exclusively locked and referenced and can be an inode
1860 * or an existing indirect block within the inode.
1862 * On return (*parentp) will be modified to point at the deepest parent chain
1863 * element encountered during the search, as a helper for an insertion or
1864 * deletion. The new (*parentp) will be locked and referenced and the old
1865 * will be unlocked and dereferenced (no change if they are both the same).
1867 * The matching chain will be returned exclusively locked. If NOLOCK is
1868 * requested the chain will be returned only referenced.
1870 * NULL is returned if no match was found, but (*parentp) will still
1871 * potentially be adjusted.
1873 * On return (*key_nextp) will point to an iterative value for key_beg.
1874 * (If NULL is returned (*key_nextp) is set to key_end).
1876 * This function will also recurse up the chain if the key is not within the
1877 * current parent's range. (*parentp) can never be set to NULL. An iteration
1878 * can simply allow (*parentp) to float inside the loop.
1880 * NOTE! chain->data is not always resolved. By default it will not be
1881 * resolved for BREF_TYPE_DATA, FREEMAP_NODE, or FREEMAP_LEAF. Use
1882 * HAMMER2_LOOKUP_ALWAYS to force resolution (but be careful w/
1883 * BREF_TYPE_DATA as the device buffer can alias the logical file
1887 hammer2_chain_lookup(hammer2_chain_t **parentp, hammer2_key_t *key_nextp,
1888 hammer2_key_t key_beg, hammer2_key_t key_end,
1889 int *cache_indexp, int flags)
1891 hammer2_mount_t *hmp;
1892 hammer2_chain_t *parent;
1893 hammer2_chain_t *chain;
1894 hammer2_blockref_t *base;
1895 hammer2_blockref_t *bref;
1896 hammer2_blockref_t bcopy;
1897 hammer2_key_t scan_beg;
1898 hammer2_key_t scan_end;
1899 hammer2_chain_core_t *above;
1901 int how_always = HAMMER2_RESOLVE_ALWAYS;
1902 int how_maybe = HAMMER2_RESOLVE_MAYBE;
1905 if (flags & HAMMER2_LOOKUP_ALWAYS) {
1906 how_maybe = how_always;
1907 how = HAMMER2_RESOLVE_ALWAYS;
1908 } else if (flags & (HAMMER2_LOOKUP_NODATA | HAMMER2_LOOKUP_NOLOCK)) {
1909 how = HAMMER2_RESOLVE_NEVER;
1911 how = HAMMER2_RESOLVE_MAYBE;
1913 if (flags & (HAMMER2_LOOKUP_SHARED | HAMMER2_LOOKUP_NOLOCK)) {
1914 how_maybe |= HAMMER2_RESOLVE_SHARED;
1915 how_always |= HAMMER2_RESOLVE_SHARED;
1916 how |= HAMMER2_RESOLVE_SHARED;
1920 * Recurse (*parentp) upward if necessary until the parent completely
1921 * encloses the key range or we hit the inode.
1923 * This function handles races against the flusher doing a delete-
1924 * duplicate above us and re-homes the parent to the duplicate in
1925 * that case, otherwise we'd wind up recursing down a stale chain.
1930 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
1931 parent->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
1932 scan_beg = parent->bref.key;
1933 scan_end = scan_beg +
1934 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
1935 if (key_beg >= scan_beg && key_end <= scan_end)
1937 parent = hammer2_chain_getparent(parentp, how_maybe);
1942 * Locate the blockref array. Currently we do a fully associative
1943 * search through the array.
1945 switch(parent->bref.type) {
1946 case HAMMER2_BREF_TYPE_INODE:
1948 * Special shortcut for embedded data returns the inode
1949 * itself. Callers must detect this condition and access
1950 * the embedded data (the strategy code does this for us).
1952 * This is only applicable to regular files and softlinks.
1954 if (parent->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
1955 if (flags & HAMMER2_LOOKUP_NOLOCK)
1956 hammer2_chain_ref(parent);
1958 hammer2_chain_lock(parent, how_always);
1959 *key_nextp = key_end + 1;
1962 base = &parent->data->ipdata.u.blockset.blockref[0];
1963 count = HAMMER2_SET_COUNT;
1965 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1966 case HAMMER2_BREF_TYPE_INDIRECT:
1968 * Handle MATCHIND on the parent
1970 if (flags & HAMMER2_LOOKUP_MATCHIND) {
1971 scan_beg = parent->bref.key;
1972 scan_end = scan_beg +
1973 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
1974 if (key_beg == scan_beg && key_end == scan_end) {
1976 hammer2_chain_lock(chain, how_maybe);
1977 *key_nextp = scan_end + 1;
1982 * Optimize indirect blocks in the INITIAL state to avoid
1985 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
1988 if (parent->data == NULL)
1989 panic("parent->data is NULL");
1990 base = &parent->data->npdata[0];
1992 count = parent->bytes / sizeof(hammer2_blockref_t);
1994 case HAMMER2_BREF_TYPE_VOLUME:
1995 base = &hmp->voldata.sroot_blockset.blockref[0];
1996 count = HAMMER2_SET_COUNT;
1998 case HAMMER2_BREF_TYPE_FREEMAP:
1999 base = &hmp->voldata.freemap_blockset.blockref[0];
2000 count = HAMMER2_SET_COUNT;
2003 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
2005 base = NULL; /* safety */
2006 count = 0; /* safety */
2010 * Merged scan to find next candidate.
2012 * hammer2_base_*() functions require the above->live_* fields
2013 * to be synchronized.
2015 * We need to hold the spinlock to access the block array and RB tree
2016 * and to interlock chain creation.
2018 above = parent->core;
2019 if ((parent->core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0)
2020 hammer2_chain_countbrefs(parent, base, count);
2025 spin_lock(&above->cst.spin);
2026 chain = hammer2_combined_find(parent, base, count,
2027 cache_indexp, key_nextp,
2028 key_beg, key_end, &bref);
2031 * Exhausted parent chain, iterate.
2034 spin_unlock(&above->cst.spin);
2035 if (key_beg == key_end) /* short cut single-key case */
2037 return (hammer2_chain_next(parentp, NULL, key_nextp,
2039 cache_indexp, flags));
2043 * Selected from blockref or in-memory chain.
2045 if (chain == NULL) {
2047 spin_unlock(&above->cst.spin);
2048 chain = hammer2_chain_get(parent, &bcopy);
2049 if (chain == NULL) {
2050 kprintf("retry lookup parent %p keys %016jx:%016jx\n",
2051 parent, key_beg, key_end);
2054 if (bcmp(&bcopy, bref, sizeof(bcopy))) {
2055 hammer2_chain_drop(chain);
2059 hammer2_chain_ref(chain);
2060 spin_unlock(&above->cst.spin);
2062 /* chain is referenced but not locked */
2065 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX)
2067 * NOTE: chain's key range is not relevant as there might be
2068 * one-offs within the range that are not deleted.
2070 if (chain->flags & HAMMER2_CHAIN_DELETED) {
2071 hammer2_chain_drop(chain);
2072 key_beg = *key_nextp;
2073 if (key_beg == 0 || key_beg > key_end)
2079 * If the chain element is an indirect block it becomes the new
2080 * parent and we loop on it. We must maintain our top-down locks
2081 * to prevent the flusher from interfering (i.e. doing a
2082 * delete-duplicate and leaving us recursing down a deleted chain).
2084 * The parent always has to be locked with at least RESOLVE_MAYBE
2085 * so we can access its data. It might need a fixup if the caller
2086 * passed incompatible flags. Be careful not to cause a deadlock
2087 * as a data-load requires an exclusive lock.
2089 * If HAMMER2_LOOKUP_MATCHIND is set and the indirect block's key
2090 * range is within the requested key range we return the indirect
2091 * block and do NOT loop. This is usually only used to acquire
2094 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
2095 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2096 hammer2_chain_lock(chain, how_maybe | HAMMER2_RESOLVE_NOREF);
2097 hammer2_chain_unlock(parent);
2098 *parentp = parent = chain;
2102 hammer2_chain_lock(chain, how | HAMMER2_RESOLVE_NOREF);
2105 * All done, return the chain
2111 * After having issued a lookup we can iterate all matching keys.
2113 * If chain is non-NULL we continue the iteration from just after it's index.
2115 * If chain is NULL we assume the parent was exhausted and continue the
2116 * iteration at the next parent.
2118 * parent must be locked on entry and remains locked throughout. chain's
2119 * lock status must match flags. Chain is always at least referenced.
2121 * WARNING! The MATCHIND flag does not apply to this function.
2124 hammer2_chain_next(hammer2_chain_t **parentp, hammer2_chain_t *chain,
2125 hammer2_key_t *key_nextp,
2126 hammer2_key_t key_beg, hammer2_key_t key_end,
2127 int *cache_indexp, int flags)
2129 hammer2_chain_t *parent;
2133 * Calculate locking flags for upward recursion.
2135 how_maybe = HAMMER2_RESOLVE_MAYBE;
2136 if (flags & (HAMMER2_LOOKUP_SHARED | HAMMER2_LOOKUP_NOLOCK))
2137 how_maybe |= HAMMER2_RESOLVE_SHARED;
2142 * Calculate the next index and recalculate the parent if necessary.
2145 key_beg = chain->bref.key +
2146 ((hammer2_key_t)1 << chain->bref.keybits);
2147 if (flags & HAMMER2_LOOKUP_NOLOCK)
2148 hammer2_chain_drop(chain);
2150 hammer2_chain_unlock(chain);
2153 * Any scan where the lookup returned degenerate data embedded
2154 * in the inode has an invalid index and must terminate.
2156 if (chain == parent)
2158 if (key_beg == 0 || key_beg > key_end)
2161 } else if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT &&
2162 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2164 * We reached the end of the iteration.
2169 * Continue iteration with next parent unless the current
2170 * parent covers the range.
2172 key_beg = parent->bref.key +
2173 ((hammer2_key_t)1 << parent->bref.keybits);
2174 if (key_beg == 0 || key_beg > key_end)
2176 parent = hammer2_chain_getparent(parentp, how_maybe);
2182 return (hammer2_chain_lookup(parentp, key_nextp,
2184 cache_indexp, flags));
2188 * Create and return a new hammer2 system memory structure of the specified
2189 * key, type and size and insert it under (*parentp). This is a full
2190 * insertion, based on the supplied key/keybits, and may involve creating
2191 * indirect blocks and moving other chains around via delete/duplicate.
2193 * (*parentp) must be exclusive locked and may be replaced on return
2194 * depending on how much work the function had to do.
2196 * (*chainp) usually starts out NULL and returns the newly created chain,
2197 * but if the caller desires the caller may allocate a disconnected chain
2198 * and pass it in instead. (It is also possible for the caller to use
2199 * chain_duplicate() to create a disconnected chain, manipulate it, then
2200 * pass it into this function to insert it).
2202 * This function should NOT be used to insert INDIRECT blocks. It is
2203 * typically used to create/insert inodes and data blocks.
2205 * Caller must pass-in an exclusively locked parent the new chain is to
2206 * be inserted under, and optionally pass-in a disconnected, exclusively
2207 * locked chain to insert (else we create a new chain). The function will
2208 * adjust (*parentp) as necessary, create or connect the chain, and
2209 * return an exclusively locked chain in *chainp.
2212 hammer2_chain_create(hammer2_trans_t *trans, hammer2_chain_t **parentp,
2213 hammer2_chain_t **chainp,
2214 hammer2_key_t key, int keybits, int type, size_t bytes)
2216 hammer2_mount_t *hmp;
2217 hammer2_chain_t *chain;
2218 hammer2_chain_t *parent = *parentp;
2219 hammer2_chain_core_t *above;
2220 hammer2_blockref_t *base;
2221 hammer2_blockref_t dummy;
2226 above = parent->core;
2227 KKASSERT(ccms_thread_lock_owned(&above->cst));
2231 if (chain == NULL) {
2233 * First allocate media space and construct the dummy bref,
2234 * then allocate the in-memory chain structure. Set the
2235 * INITIAL flag for fresh chains which do not have embedded
2238 bzero(&dummy, sizeof(dummy));
2241 dummy.keybits = keybits;
2242 dummy.data_off = hammer2_getradix(bytes);
2243 dummy.methods = parent->bref.methods;
2244 chain = hammer2_chain_alloc(hmp, parent->pmp, trans, &dummy);
2245 hammer2_chain_core_alloc(trans, chain, NULL);
2248 * Lock the chain manually, chain_lock will load the chain
2249 * which we do NOT want to do. (note: chain->refs is set
2250 * to 1 by chain_alloc() for us, but lockcnt is not).
2253 ccms_thread_lock(&chain->core->cst, CCMS_STATE_EXCLUSIVE);
2257 * We do NOT set INITIAL here (yet). INITIAL is only
2258 * used for indirect blocks.
2260 * Recalculate bytes to reflect the actual media block
2263 bytes = (hammer2_off_t)1 <<
2264 (int)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
2265 chain->bytes = bytes;
2268 case HAMMER2_BREF_TYPE_VOLUME:
2269 case HAMMER2_BREF_TYPE_FREEMAP:
2270 panic("hammer2_chain_create: called with volume type");
2272 case HAMMER2_BREF_TYPE_INODE:
2273 KKASSERT(bytes == HAMMER2_INODE_BYTES);
2274 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
2275 chain->data = kmalloc(sizeof(chain->data->ipdata),
2276 hmp->mchain, M_WAITOK | M_ZERO);
2278 case HAMMER2_BREF_TYPE_INDIRECT:
2279 panic("hammer2_chain_create: cannot be used to"
2280 "create indirect block");
2282 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2283 panic("hammer2_chain_create: cannot be used to"
2284 "create freemap root or node");
2286 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2287 KKASSERT(bytes == sizeof(chain->data->bmdata));
2288 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
2289 chain->data = kmalloc(sizeof(chain->data->bmdata),
2290 hmp->mchain, M_WAITOK | M_ZERO);
2292 case HAMMER2_BREF_TYPE_DATA:
2295 * leave chain->data NULL, set INITIAL
2297 KKASSERT(chain->data == NULL);
2298 atomic_set_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
2303 * Potentially update the existing chain's key/keybits.
2305 * Do NOT mess with the current state of the INITIAL flag.
2307 chain->bref.key = key;
2308 chain->bref.keybits = keybits;
2309 KKASSERT(chain->above == NULL);
2313 * Calculate how many entries we have in the blockref array and
2314 * determine if an indirect block is required.
2317 above = parent->core;
2319 switch(parent->bref.type) {
2320 case HAMMER2_BREF_TYPE_INODE:
2321 KKASSERT((parent->data->ipdata.op_flags &
2322 HAMMER2_OPFLAG_DIRECTDATA) == 0);
2323 KKASSERT(parent->data != NULL);
2324 base = &parent->data->ipdata.u.blockset.blockref[0];
2325 count = HAMMER2_SET_COUNT;
2327 case HAMMER2_BREF_TYPE_INDIRECT:
2328 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2329 if (parent->flags & HAMMER2_CHAIN_INITIAL)
2332 base = &parent->data->npdata[0];
2333 count = parent->bytes / sizeof(hammer2_blockref_t);
2335 case HAMMER2_BREF_TYPE_VOLUME:
2336 KKASSERT(parent->data != NULL);
2337 base = &hmp->voldata.sroot_blockset.blockref[0];
2338 count = HAMMER2_SET_COUNT;
2340 case HAMMER2_BREF_TYPE_FREEMAP:
2341 KKASSERT(parent->data != NULL);
2342 base = &hmp->voldata.freemap_blockset.blockref[0];
2343 count = HAMMER2_SET_COUNT;
2346 panic("hammer2_chain_create: unrecognized blockref type: %d",
2354 * Make sure we've counted the brefs
2356 if ((parent->core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0)
2357 hammer2_chain_countbrefs(parent, base, count);
2359 KKASSERT(above->live_count >= 0 && above->live_count <= count);
2362 * If no free blockref could be found we must create an indirect
2363 * block and move a number of blockrefs into it. With the parent
2364 * locked we can safely lock each child in order to delete+duplicate
2365 * it without causing a deadlock.
2367 * This may return the new indirect block or the old parent depending
2368 * on where the key falls. NULL is returned on error.
2370 if (above->live_count == count) {
2371 hammer2_chain_t *nparent;
2373 nparent = hammer2_chain_create_indirect(trans, parent,
2376 if (nparent == NULL) {
2378 hammer2_chain_drop(chain);
2382 if (parent != nparent) {
2383 hammer2_chain_unlock(parent);
2384 parent = *parentp = nparent;
2390 * Link the chain into its parent. Later on we will have to set
2391 * the MOVED bit in situations where we don't mark the new chain
2392 * as being modified.
2394 if (chain->above != NULL)
2395 panic("hammer2: hammer2_chain_create: chain already connected");
2396 KKASSERT(chain->above == NULL);
2397 KKASSERT((chain->flags & HAMMER2_CHAIN_DELETED) == 0);
2398 hammer2_chain_insert(above, NULL, chain,
2399 HAMMER2_CHAIN_INSERT_SPIN |
2400 HAMMER2_CHAIN_INSERT_LIVE);
2404 * Mark the newly created chain modified.
2406 * Device buffers are not instantiated for DATA elements
2407 * as these are handled by logical buffers.
2409 * Indirect and freemap node indirect blocks are handled
2410 * by hammer2_chain_create_indirect() and not by this
2413 * Data for all other bref types is expected to be
2414 * instantiated (INODE, LEAF).
2416 switch(chain->bref.type) {
2417 case HAMMER2_BREF_TYPE_DATA:
2418 hammer2_chain_modify(trans, &chain,
2419 HAMMER2_MODIFY_OPTDATA |
2420 HAMMER2_MODIFY_ASSERTNOCOPY);
2422 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2423 case HAMMER2_BREF_TYPE_INODE:
2424 hammer2_chain_modify(trans, &chain,
2425 HAMMER2_MODIFY_ASSERTNOCOPY);
2429 * Remaining types are not supported by this function.
2430 * In particular, INDIRECT and LEAF_NODE types are
2431 * handled by create_indirect().
2433 panic("hammer2_chain_create: bad type: %d",
2440 * When reconnecting a chain we must set MOVED and setsubmod
2441 * so the flush recognizes that it must update the bref in
2444 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2445 hammer2_chain_ref(chain);
2446 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
2449 hammer2_chain_setsubmod(trans, chain);
2458 * Replace (*chainp) with a duplicate in-memory chain structure which shares
2459 * the same core and media state as the orignal. The original *chainp is
2460 * unlocked and the replacement will be returned locked.
2462 * The old chain may or may not be in a DELETED state. This new chain will
2463 * be live (not deleted).
2465 * The new chain will be marked modified for the current transaction.
2467 * If (parent) is non-NULL then the new duplicated chain is inserted under
2470 * If (parent) is NULL then the new duplicated chain is not inserted anywhere,
2471 * similar to if it had just been chain_alloc()'d (suitable for passing into
2472 * hammer2_chain_create() after this function returns).
2474 * WARNING! This is not a snapshot. Changes made underneath either the old
2475 * or new chain will affect both.
2477 static void hammer2_chain_dup_fixup(hammer2_chain_t *ochain,
2478 hammer2_chain_t *nchain);
2481 hammer2_chain_duplicate(hammer2_trans_t *trans, hammer2_chain_t **parentp,
2482 hammer2_chain_t **chainp, hammer2_blockref_t *bref,
2485 hammer2_mount_t *hmp;
2486 hammer2_chain_t *parent;
2487 hammer2_chain_t *ochain;
2488 hammer2_chain_t *nchain;
2489 hammer2_chain_core_t *above;
2493 * We want nchain to be our go-to live chain, but ochain may be in
2494 * a MODIFIED state within the current flush synchronization segment.
2495 * Force any further modifications of ochain to do another COW
2496 * operation even if modify_tid indicates that one is not needed.
2498 * WARNING! We should never resolve DATA to device buffers
2499 * (XXX allow it if the caller did?), and since
2500 * we currently do not have the logical buffer cache
2501 * buffer in-hand to fix its cached physical offset
2502 * we also force the modify code to not COW it. XXX
2507 ochain->debug_reason += 0x10000;
2509 ochain->debug_reason += 0x100000;
2512 if (ochain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2513 hammer2_chain_modify(trans, &ochain,
2514 HAMMER2_MODIFY_OPTDATA |
2515 HAMMER2_MODIFY_NOREALLOC);
2516 } else if (ochain->flags & HAMMER2_CHAIN_INITIAL) {
2517 hammer2_chain_modify(trans, &ochain,
2518 HAMMER2_MODIFY_OPTDATA);
2520 hammer2_chain_modify(trans, &ochain, 0);
2523 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_FORCECOW);
2526 * Now create a duplicate of the chain structure, associating
2527 * it with the same core, making it the same size, pointing it
2528 * to the same bref (the same media block).
2530 * Give the duplicate the same modify_tid that we previously
2531 * ensured was sufficiently advanced to trigger a block table
2532 * insertion on flush.
2534 * NOTE: bref.mirror_tid duplicated by virtue of bref copy in
2535 * hammer2_chain_alloc()
2538 bref = &ochain->bref;
2540 nchain = hammer2_chain_alloc(hmp, NULL, trans, bref);
2541 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_SNAPSHOT);
2543 nchain = hammer2_chain_alloc(hmp, ochain->pmp, trans, bref);
2545 hammer2_chain_core_alloc(trans, nchain, ochain);
2546 bytes = (hammer2_off_t)1 <<
2547 (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
2548 nchain->bytes = bytes;
2549 nchain->modify_tid = ochain->modify_tid;
2550 if (ochain->flags & HAMMER2_CHAIN_INITIAL)
2551 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_INITIAL);
2554 * Fixup (copy) any embedded data. Non-embedded data relies on the
2555 * media block. We must unlock ochain before we can access nchain's
2556 * media block because they might share the same bp and deadlock if
2559 hammer2_chain_lock(nchain, HAMMER2_RESOLVE_NEVER |
2560 HAMMER2_RESOLVE_NOREF);
2561 hammer2_chain_dup_fixup(ochain, nchain);
2562 /* nchain has 1 ref */
2563 hammer2_chain_unlock(ochain);
2564 KKASSERT((ochain->flags & HAMMER2_CHAIN_EMBEDDED) ||
2565 ochain->data == NULL);
2568 * Place nchain in the modified state, instantiate media data
2569 * if necessary. Because modify_tid is already completely
2570 * synchronized this should not result in a delete-duplicate.
2572 * We want nchain at the target to look like a new insertion.
2573 * Forcing the modification to be INPLACE accomplishes this
2574 * because we get the same nchain with an updated modify_tid.
2576 if (nchain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2577 hammer2_chain_modify(trans, &nchain,
2578 HAMMER2_MODIFY_OPTDATA |
2579 HAMMER2_MODIFY_NOREALLOC |
2580 HAMMER2_MODIFY_INPLACE);
2581 } else if (nchain->flags & HAMMER2_CHAIN_INITIAL) {
2582 hammer2_chain_modify(trans, &nchain,
2583 HAMMER2_MODIFY_OPTDATA |
2584 HAMMER2_MODIFY_INPLACE);
2586 hammer2_chain_modify(trans, &nchain,
2587 HAMMER2_MODIFY_INPLACE);
2591 * If parent is not NULL the duplicated chain will be entered under
2592 * the parent and the MOVED bit set.
2594 * Having both chains locked is extremely important for atomicy.
2596 if (parentp && (parent = *parentp) != NULL) {
2597 above = parent->core;
2598 KKASSERT(ccms_thread_lock_owned(&above->cst));
2599 KKASSERT((nchain->flags & HAMMER2_CHAIN_DELETED) == 0);
2600 KKASSERT(parent->refs > 0);
2602 hammer2_chain_create(trans, parentp, &nchain,
2603 nchain->bref.key, nchain->bref.keybits,
2604 nchain->bref.type, nchain->bytes);
2607 if ((nchain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2608 hammer2_chain_ref(nchain);
2609 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_MOVED);
2611 hammer2_chain_setsubmod(trans, nchain);
2616 * Unconditionally set MOVED to force the parent blockrefs to
2617 * update, and adjust update_hi below nchain so nchain's
2618 * blockrefs are updated with the new attachment.
2620 if (nchain->core->update_hi < trans->sync_tid) {
2621 spin_lock(&nchain->core->cst.spin);
2622 if (nchain->core->update_hi < trans->sync_tid)
2623 nchain->core->update_hi = trans->sync_tid;
2624 spin_unlock(&nchain->core->cst.spin);
2632 * Special in-place delete-duplicate sequence which does not require a
2633 * locked parent. (*chainp) is marked DELETED and atomically replaced
2634 * with a duplicate. Atomicy is at the very-fine spin-lock level in
2635 * order to ensure that lookups do not race us.
2637 * If the old chain is already marked deleted the new chain will also be
2638 * marked deleted. This case can occur when an inode is removed from the
2639 * filesystem but programs still have an open descriptor to it, and during
2640 * flushes when the flush needs to operate on a chain that is deleted in
2641 * the live view but still alive in the flush view.
2643 * The new chain will be marked modified for the current transaction.
2646 hammer2_chain_delete_duplicate(hammer2_trans_t *trans, hammer2_chain_t **chainp,
2649 hammer2_mount_t *hmp;
2650 hammer2_chain_t *ochain;
2651 hammer2_chain_t *nchain;
2652 hammer2_chain_core_t *above;
2655 if (hammer2_debug & 0x20000)
2659 * Note that we do not have to call setsubmod on ochain, calling it
2660 * on nchain is sufficient.
2665 ochain->debug_reason += 0x1000;
2666 if ((ochain->debug_reason & 0xF000) > 0x4000) {
2667 kprintf("ochain %p\n", ochain);
2670 if (ochain->bref.type == HAMMER2_BREF_TYPE_INODE) {
2671 KKASSERT(ochain->data);
2675 * First create a duplicate of the chain structure.
2676 * (nchain is allocated with one ref).
2678 * In the case where nchain inherits ochains core, nchain is
2679 * effectively locked due to ochain being locked (and sharing the
2680 * core), until we can give nchain its own official ock.
2682 nchain = hammer2_chain_alloc(hmp, ochain->pmp, trans, &ochain->bref);
2683 if (flags & HAMMER2_DELDUP_RECORE)
2684 hammer2_chain_core_alloc(trans, nchain, NULL);
2686 hammer2_chain_core_alloc(trans, nchain, ochain);
2687 above = ochain->above;
2689 bytes = (hammer2_off_t)1 <<
2690 (int)(ochain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
2691 nchain->bytes = bytes;
2694 * Duplicate inherits ochain's live state including its modification
2695 * state. This function disposes of the original. Because we are
2696 * doing this in-place under the same parent the block array
2697 * inserted/deleted state does not change.
2699 * The caller isn't expected to make further modifications of ochain
2700 * but set the FORCECOW bit anyway, just in case it does. If ochain
2701 * was previously marked FORCECOW we also flag nchain FORCECOW
2702 * (used during hardlink splits).
2704 * NOTE: bref.mirror_tid duplicated by virtue of bref copy in
2705 * hammer2_chain_alloc()
2707 nchain->data_count += ochain->data_count;
2708 nchain->inode_count += ochain->inode_count;
2709 atomic_set_int(&nchain->flags,
2710 ochain->flags & (HAMMER2_CHAIN_INITIAL |
2711 HAMMER2_CHAIN_FORCECOW));
2712 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_FORCECOW);
2715 * Lock nchain so both chains are now locked (extremely important
2716 * for atomicy). Mark ochain deleted and reinsert into the topology
2717 * and insert nchain all in one go.
2719 * If the ochain is already deleted it is left alone and nchain
2720 * is inserted into the topology as a deleted chain. This is
2721 * important because it allows ongoing operations to be executed
2722 * on a deleted inode which still has open descriptors.
2724 * The deleted case can also occur when a flush delete-duplicates
2725 * a node which is being concurrently modified by ongoing operations
2726 * in a later transaction. This creates a problem because the flush
2727 * is intended to update blockrefs which then propagate, allowing
2728 * the original covering in-memory chains to be freed up. In this
2729 * situation the flush code does NOT free the original covering
2730 * chains and will re-apply them to successive copies.
2732 hammer2_chain_lock(nchain, HAMMER2_RESOLVE_NEVER);
2733 hammer2_chain_dup_fixup(ochain, nchain);
2734 /* extra ref still present from original allocation */
2736 KKASSERT(ochain->flags & HAMMER2_CHAIN_ONRBTREE);
2737 spin_lock(&above->cst.spin);
2738 KKASSERT(ochain->flags & HAMMER2_CHAIN_ONRBTREE);
2741 * Ultimately nchain->modify_tid will be set to trans->sync_tid,
2742 * but we can't do that here because we want to call
2743 * hammer2_chain_modify() to reallocate the block (if necessary).
2745 nchain->modify_tid = ochain->modify_tid;
2747 if (ochain->flags & HAMMER2_CHAIN_DELETED) {
2748 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_DELETED);
2749 if (ochain->delete_tid > trans->sync_tid) {
2751 * delete-duplicate a chain deleted in a later
2752 * transaction. Only allowed on chains created
2753 * before or during the current transaction (flush
2754 * code should filter out chains created after the
2755 * current transaction).
2757 * To make this work is a bit of a hack. We convert
2758 * ochain's delete_tid to the current sync_tid and
2759 * create a nchain which sets up ochains original
2762 * This effectively forces ochain to flush as a
2763 * deletion and nchain as a creation. Thus MOVED
2764 * must be set in ochain (it should already be
2765 * set since it's original delete_tid could not
2766 * have been flushed yet). Since ochain's delete_tid
2767 * has been moved down to sync_tid, a re-flush at
2768 * sync_tid won't try to delete-duplicate ochain
2771 KKASSERT(ochain->modify_tid <= trans->sync_tid);
2772 nchain->delete_tid = ochain->delete_tid;
2773 ochain->delete_tid = trans->sync_tid;
2774 KKASSERT(ochain->flags & HAMMER2_CHAIN_MOVED);
2775 } else if (ochain->delete_tid == trans->sync_tid) {
2777 * ochain was deleted in the current transaction
2779 nchain->delete_tid = trans->sync_tid;
2782 * ochain was deleted in a prior transaction.
2783 * create and delete nchain in the current
2786 nchain->delete_tid = trans->sync_tid;
2788 hammer2_chain_insert(above, ochain->inlayer, nchain, 0);
2790 KKASSERT(trans->sync_tid >= ochain->modify_tid);
2791 ochain->delete_tid = trans->sync_tid;
2792 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_DELETED);
2793 atomic_add_int(&above->live_count, -1);
2794 hammer2_chain_insert(above, NULL, nchain,
2795 HAMMER2_CHAIN_INSERT_LIVE);
2798 if ((ochain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2799 hammer2_chain_ref(ochain);
2800 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_MOVED);
2802 spin_unlock(&above->cst.spin);
2805 * ochain must be unlocked because ochain and nchain might share
2806 * a buffer cache buffer, so we need to release it so nchain can
2807 * potentially obtain it.
2809 hammer2_chain_unlock(ochain);
2812 * Finishing fixing up nchain. A new block will be allocated if
2813 * crossing a synchronization point (meta-data only).
2815 if (nchain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2816 hammer2_chain_modify(trans, &nchain,
2817 HAMMER2_MODIFY_OPTDATA |
2818 HAMMER2_MODIFY_NOREALLOC |
2819 HAMMER2_MODIFY_INPLACE);
2820 } else if (nchain->flags & HAMMER2_CHAIN_INITIAL) {
2821 hammer2_chain_modify(trans, &nchain,
2822 HAMMER2_MODIFY_OPTDATA |
2823 HAMMER2_MODIFY_INPLACE);
2825 hammer2_chain_modify(trans, &nchain,
2826 HAMMER2_MODIFY_INPLACE);
2828 hammer2_chain_drop(nchain);
2831 * Unconditionally set MOVED to force the parent blockrefs to
2832 * update as the chain_modify() above won't necessarily do it.
2834 * Adjust update_hi below nchain so nchain's blockrefs are updated
2835 * with the new attachment.
2837 if ((nchain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2838 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_MOVED);
2839 hammer2_chain_ref(nchain);
2842 if (nchain->core->update_hi < trans->sync_tid) {
2843 spin_lock(&nchain->core->cst.spin);
2844 if (nchain->core->update_hi < trans->sync_tid)
2845 nchain->core->update_hi = trans->sync_tid;
2846 spin_unlock(&nchain->core->cst.spin);
2849 hammer2_chain_setsubmod(trans, nchain);
2854 * Helper function to fixup inodes. The caller procedure stack may hold
2855 * multiple locks on ochain if it represents an inode, preventing our
2856 * unlock from retiring its state to the buffer cache.
2858 * In this situation any attempt to access the buffer cache could result
2859 * either in stale data or a deadlock. Work around the problem by copying
2860 * the embedded data directly.
2864 hammer2_chain_dup_fixup(hammer2_chain_t *ochain, hammer2_chain_t *nchain)
2866 if (ochain->data == NULL)
2868 switch(ochain->bref.type) {
2869 case HAMMER2_BREF_TYPE_INODE:
2870 KKASSERT(nchain->data == NULL);
2871 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_EMBEDDED);
2872 nchain->data = kmalloc(sizeof(nchain->data->ipdata),
2873 ochain->hmp->mchain, M_WAITOK | M_ZERO);
2874 nchain->data->ipdata = ochain->data->ipdata;
2876 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2877 KKASSERT(nchain->data == NULL);
2878 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_EMBEDDED);
2879 nchain->data = kmalloc(sizeof(nchain->data->bmdata),
2880 ochain->hmp->mchain, M_WAITOK | M_ZERO);
2881 bcopy(ochain->data->bmdata,
2882 nchain->data->bmdata,
2883 sizeof(nchain->data->bmdata));
2891 * Create a snapshot of the specified {parent, ochain} with the specified
2892 * label. The originating hammer2_inode must be exclusively locked for
2895 * The ioctl code has already synced the filesystem.
2898 hammer2_chain_snapshot(hammer2_trans_t *trans, hammer2_chain_t **ochainp,
2899 hammer2_ioc_pfs_t *pfs)
2901 hammer2_mount_t *hmp;
2902 hammer2_chain_t *ochain = *ochainp;
2903 hammer2_chain_t *nchain;
2904 hammer2_inode_data_t *ipdata;
2905 hammer2_inode_t *nip;
2912 kprintf("snapshot %s ochain->refs %d ochain->flags %08x\n",
2913 pfs->name, ochain->refs, ochain->flags);
2915 name_len = strlen(pfs->name);
2916 lhc = hammer2_dirhash(pfs->name, name_len);
2919 opfs_clid = ochain->data->ipdata.pfs_clid;
2924 * Create the snapshot directory under the super-root
2926 * Set PFS type, generate a unique filesystem id, and generate
2927 * a cluster id. Use the same clid when snapshotting a PFS root,
2928 * which theoretically allows the snapshot to be used as part of
2929 * the same cluster (perhaps as a cache).
2931 * Copy the (flushed) ochain's blockref array. Theoretically we
2932 * could use chain_duplicate() but it becomes difficult to disentangle
2933 * the shared core so for now just brute-force it.
2939 nip = hammer2_inode_create(trans, hmp->sroot, &vat, proc0.p_ucred,
2940 pfs->name, name_len, &nchain, &error);
2943 ipdata = hammer2_chain_modify_ip(trans, nip, &nchain, 0);
2944 ipdata->pfs_type = HAMMER2_PFSTYPE_SNAPSHOT;
2945 kern_uuidgen(&ipdata->pfs_fsid, 1);
2946 if (ochain->flags & HAMMER2_CHAIN_PFSROOT)
2947 ipdata->pfs_clid = opfs_clid;
2949 kern_uuidgen(&ipdata->pfs_clid, 1);
2950 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_PFSROOT);
2951 ipdata->u.blockset = ochain->data->ipdata.u.blockset;
2953 hammer2_inode_unlock_ex(nip, nchain);
2959 * Create an indirect block that covers one or more of the elements in the
2960 * current parent. Either returns the existing parent with no locking or
2961 * ref changes or returns the new indirect block locked and referenced
2962 * and leaving the original parent lock/ref intact as well.
2964 * If an error occurs, NULL is returned and *errorp is set to the error.
2966 * The returned chain depends on where the specified key falls.
2968 * The key/keybits for the indirect mode only needs to follow three rules:
2970 * (1) That all elements underneath it fit within its key space and
2972 * (2) That all elements outside it are outside its key space.
2974 * (3) When creating the new indirect block any elements in the current
2975 * parent that fit within the new indirect block's keyspace must be
2976 * moved into the new indirect block.
2978 * (4) The keyspace chosen for the inserted indirect block CAN cover a wider
2979 * keyspace the the current parent, but lookup/iteration rules will
2980 * ensure (and must ensure) that rule (2) for all parents leading up
2981 * to the nearest inode or the root volume header is adhered to. This
2982 * is accomplished by always recursing through matching keyspaces in
2983 * the hammer2_chain_lookup() and hammer2_chain_next() API.
2985 * The current implementation calculates the current worst-case keyspace by
2986 * iterating the current parent and then divides it into two halves, choosing
2987 * whichever half has the most elements (not necessarily the half containing
2988 * the requested key).
2990 * We can also opt to use the half with the least number of elements. This
2991 * causes lower-numbered keys (aka logical file offsets) to recurse through
2992 * fewer indirect blocks and higher-numbered keys to recurse through more.
2993 * This also has the risk of not moving enough elements to the new indirect
2994 * block and being forced to create several indirect blocks before the element
2997 * Must be called with an exclusively locked parent.
2999 static int hammer2_chain_indkey_freemap(hammer2_chain_t *parent,
3000 hammer2_key_t *keyp, int keybits,
3001 hammer2_blockref_t *base, int count);
3002 static int hammer2_chain_indkey_normal(hammer2_chain_t *parent,
3003 hammer2_key_t *keyp, int keybits,
3004 hammer2_blockref_t *base, int count);
3007 hammer2_chain_create_indirect(hammer2_trans_t *trans, hammer2_chain_t *parent,
3008 hammer2_key_t create_key, int create_bits,
3009 int for_type, int *errorp)
3011 hammer2_mount_t *hmp;
3012 hammer2_chain_core_t *above;
3013 hammer2_chain_core_t *icore;
3014 hammer2_blockref_t *base;
3015 hammer2_blockref_t *bref;
3016 hammer2_blockref_t bcopy;
3017 hammer2_chain_t *chain;
3018 hammer2_chain_t *ichain;
3019 hammer2_chain_t dummy;
3020 hammer2_key_t key = create_key;
3021 hammer2_key_t key_beg;
3022 hammer2_key_t key_end;
3023 hammer2_key_t key_next;
3024 int keybits = create_bits;
3031 * Calculate the base blockref pointer or NULL if the chain
3032 * is known to be empty. We need to calculate the array count
3033 * for RB lookups either way.
3037 KKASSERT(ccms_thread_lock_owned(&parent->core->cst));
3038 above = parent->core;
3040 /*hammer2_chain_modify(trans, &parent, HAMMER2_MODIFY_OPTDATA);*/
3041 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
3044 switch(parent->bref.type) {
3045 case HAMMER2_BREF_TYPE_INODE:
3046 count = HAMMER2_SET_COUNT;
3048 case HAMMER2_BREF_TYPE_INDIRECT:
3049 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3050 count = parent->bytes / sizeof(hammer2_blockref_t);
3052 case HAMMER2_BREF_TYPE_VOLUME:
3053 count = HAMMER2_SET_COUNT;
3055 case HAMMER2_BREF_TYPE_FREEMAP:
3056 count = HAMMER2_SET_COUNT;
3059 panic("hammer2_chain_create_indirect: "
3060 "unrecognized blockref type: %d",
3066 switch(parent->bref.type) {
3067 case HAMMER2_BREF_TYPE_INODE:
3068 base = &parent->data->ipdata.u.blockset.blockref[0];
3069 count = HAMMER2_SET_COUNT;
3071 case HAMMER2_BREF_TYPE_INDIRECT:
3072 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3073 base = &parent->data->npdata[0];
3074 count = parent->bytes / sizeof(hammer2_blockref_t);
3076 case HAMMER2_BREF_TYPE_VOLUME:
3077 base = &hmp->voldata.sroot_blockset.blockref[0];
3078 count = HAMMER2_SET_COUNT;
3080 case HAMMER2_BREF_TYPE_FREEMAP:
3081 base = &hmp->voldata.freemap_blockset.blockref[0];
3082 count = HAMMER2_SET_COUNT;
3085 panic("hammer2_chain_create_indirect: "
3086 "unrecognized blockref type: %d",
3094 * dummy used in later chain allocation (no longer used for lookups).
3096 bzero(&dummy, sizeof(dummy));
3097 dummy.delete_tid = HAMMER2_MAX_TID;
3100 * When creating an indirect block for a freemap node or leaf
3101 * the key/keybits must be fitted to static radix levels because
3102 * particular radix levels use particular reserved blocks in the
3105 * This routine calculates the key/radix of the indirect block
3106 * we need to create, and whether it is on the high-side or the
3109 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
3110 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
3111 keybits = hammer2_chain_indkey_freemap(parent, &key, keybits,
3114 keybits = hammer2_chain_indkey_normal(parent, &key, keybits,
3119 * Normalize the key for the radix being represented, keeping the
3120 * high bits and throwing away the low bits.
3122 key &= ~(((hammer2_key_t)1 << keybits) - 1);
3125 * How big should our new indirect block be? It has to be at least
3126 * as large as its parent.
3128 if (parent->bref.type == HAMMER2_BREF_TYPE_INODE)
3129 nbytes = HAMMER2_IND_BYTES_MIN;
3131 nbytes = HAMMER2_IND_BYTES_MAX;
3132 if (nbytes < count * sizeof(hammer2_blockref_t))
3133 nbytes = count * sizeof(hammer2_blockref_t);
3136 * Ok, create our new indirect block
3138 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
3139 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
3140 dummy.bref.type = HAMMER2_BREF_TYPE_FREEMAP_NODE;
3142 dummy.bref.type = HAMMER2_BREF_TYPE_INDIRECT;
3144 dummy.bref.key = key;
3145 dummy.bref.keybits = keybits;
3146 dummy.bref.data_off = hammer2_getradix(nbytes);
3147 dummy.bref.methods = parent->bref.methods;
3149 ichain = hammer2_chain_alloc(hmp, parent->pmp, trans, &dummy.bref);
3150 atomic_set_int(&ichain->flags, HAMMER2_CHAIN_INITIAL);
3151 hammer2_chain_core_alloc(trans, ichain, NULL);
3152 icore = ichain->core;
3153 hammer2_chain_lock(ichain, HAMMER2_RESOLVE_MAYBE);
3154 hammer2_chain_drop(ichain); /* excess ref from alloc */
3157 * We have to mark it modified to allocate its block, but use
3158 * OPTDATA to allow it to remain in the INITIAL state. Otherwise
3159 * it won't be acted upon by the flush code.
3161 * XXX leave the node unmodified, depend on the update_hi
3162 * flush to assign and modify parent blocks.
3164 hammer2_chain_modify(trans, &ichain, HAMMER2_MODIFY_OPTDATA);
3167 * Iterate the original parent and move the matching brefs into
3168 * the new indirect block.
3170 * XXX handle flushes.
3173 key_end = HAMMER2_MAX_KEY;
3175 spin_lock(&above->cst.spin);
3179 if (++loops > 8192) {
3180 spin_unlock(&above->cst.spin);
3181 panic("shit parent=%p base/count %p:%d\n",
3182 parent, base, count);
3186 * NOTE: spinlock stays intact, returned chain (if not NULL)
3187 * is not referenced or locked.
3189 chain = hammer2_combined_find(parent, base, count,
3190 &cache_index, &key_next,
3195 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3196 if (key_next == 0 || key_next > key_end)
3203 * Use the full live (not deleted) element for the scan
3204 * iteration. HAMMER2 does not allow partial replacements.
3206 * XXX should be built into hammer2_combined_find().
3208 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3211 * Skip keys that are not within the key/radix of the new
3212 * indirect block. They stay in the parent.
3214 if ((~(((hammer2_key_t)1 << keybits) - 1) &
3215 (key ^ bref->key)) != 0) {
3216 if (key_next == 0 || key_next > key_end)
3223 * Load the new indirect block by acquiring or allocating
3224 * the related chain, then move it to the new parent (ichain)
3225 * via DELETE-DUPLICATE.
3227 * WARNING! above->cst.spin must be held when parent is
3228 * modified, even though we own the full blown lock,
3229 * to deal with setsubmod and rename races.
3230 * (XXX remove this req).
3234 * Use chain already present in the RBTREE
3236 hammer2_chain_ref(chain);
3237 spin_unlock(&above->cst.spin);
3238 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER |
3239 HAMMER2_RESOLVE_NOREF);
3242 * Get chain for blockref element. _get returns NULL
3243 * on insertion race.
3246 spin_unlock(&above->cst.spin);
3247 chain = hammer2_chain_get(parent, bref);
3250 if (bcmp(&bcopy, bref, sizeof(bcopy))) {
3251 hammer2_chain_drop(chain);
3254 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER |
3255 HAMMER2_RESOLVE_NOREF);
3257 hammer2_chain_delete(trans, chain, HAMMER2_DELETE_WILLDUP);
3258 hammer2_chain_duplicate(trans, &ichain, &chain, NULL, 0);
3259 hammer2_chain_unlock(chain);
3260 KKASSERT(parent->refs > 0);
3262 spin_lock(&above->cst.spin);
3263 if (key_next == 0 || key_next > key_end)
3267 spin_unlock(&above->cst.spin);
3270 * Insert the new indirect block into the parent now that we've
3271 * cleared out some entries in the parent. We calculated a good
3272 * insertion index in the loop above (ichain->index).
3274 * We don't have to set MOVED here because we mark ichain modified
3275 * down below (so the normal modified -> flush -> set-moved sequence
3278 * The insertion shouldn't race as this is a completely new block
3279 * and the parent is locked.
3281 KKASSERT((ichain->flags & HAMMER2_CHAIN_ONRBTREE) == 0);
3282 hammer2_chain_insert(above, NULL, ichain,
3283 HAMMER2_CHAIN_INSERT_SPIN |
3284 HAMMER2_CHAIN_INSERT_LIVE);
3287 * Mark the new indirect block modified after insertion, which
3288 * will propagate up through parent all the way to the root and
3289 * also allocate the physical block in ichain for our caller,
3290 * and assign ichain->data to a pre-zero'd space (because there
3291 * is not prior data to copy into it).
3293 * We have to set update_hi in ichain's flags manually so the
3294 * flusher knows it has to recurse through it to get to all of
3295 * our moved blocks, then call setsubmod() to set the bit
3298 /*hammer2_chain_modify(trans, &ichain, HAMMER2_MODIFY_OPTDATA);*/
3299 if (ichain->core->update_hi < trans->sync_tid) {
3300 spin_lock(&ichain->core->cst.spin);
3301 if (ichain->core->update_hi < trans->sync_tid)
3302 ichain->core->update_hi = trans->sync_tid;
3303 spin_unlock(&ichain->core->cst.spin);
3305 hammer2_chain_setsubmod(trans, ichain);
3308 * Figure out what to return.
3310 if (~(((hammer2_key_t)1 << keybits) - 1) &
3311 (create_key ^ key)) {
3313 * Key being created is outside the key range,
3314 * return the original parent.
3316 hammer2_chain_unlock(ichain);
3319 * Otherwise its in the range, return the new parent.
3320 * (leave both the new and old parent locked).
3329 * Calculate the keybits and highside/lowside of the freemap node the
3330 * caller is creating.
3332 * This routine will specify the next higher-level freemap key/radix
3333 * representing the lowest-ordered set. By doing so, eventually all
3334 * low-ordered sets will be moved one level down.
3336 * We have to be careful here because the freemap reserves a limited
3337 * number of blocks for a limited number of levels. So we can't just
3338 * push indiscriminately.
3341 hammer2_chain_indkey_freemap(hammer2_chain_t *parent, hammer2_key_t *keyp,
3342 int keybits, hammer2_blockref_t *base, int count)
3344 hammer2_chain_core_t *above;
3345 hammer2_chain_t *chain;
3346 hammer2_blockref_t *bref;
3348 hammer2_key_t key_beg;
3349 hammer2_key_t key_end;
3350 hammer2_key_t key_next;
3357 above = parent->core;
3363 * Calculate the range of keys in the array being careful to skip
3364 * slots which are overridden with a deletion.
3367 key_end = HAMMER2_MAX_KEY;
3369 spin_lock(&above->cst.spin);
3372 if (++loops == 100000) {
3373 panic("indkey_freemap shit %p %p:%d\n",
3374 parent, base, count);
3376 chain = hammer2_combined_find(parent, base, count,
3377 &cache_index, &key_next,
3378 key_beg, key_end, &bref);
3385 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3386 if (key_next == 0 || key_next > key_end)
3393 * Use the full live (not deleted) element for the scan
3394 * iteration. HAMMER2 does not allow partial replacements.
3396 * XXX should be built into hammer2_combined_find().
3398 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3400 if (keybits > bref->keybits) {
3402 keybits = bref->keybits;
3403 } else if (keybits == bref->keybits && bref->key < key) {
3410 spin_unlock(&above->cst.spin);
3413 * Return the keybits for a higher-level FREEMAP_NODE covering
3417 case HAMMER2_FREEMAP_LEVEL0_RADIX:
3418 keybits = HAMMER2_FREEMAP_LEVEL1_RADIX;
3420 case HAMMER2_FREEMAP_LEVEL1_RADIX:
3421 keybits = HAMMER2_FREEMAP_LEVEL2_RADIX;
3423 case HAMMER2_FREEMAP_LEVEL2_RADIX:
3424 keybits = HAMMER2_FREEMAP_LEVEL3_RADIX;
3426 case HAMMER2_FREEMAP_LEVEL3_RADIX:
3427 keybits = HAMMER2_FREEMAP_LEVEL4_RADIX;
3429 case HAMMER2_FREEMAP_LEVEL4_RADIX:
3430 panic("hammer2_chain_indkey_freemap: level too high");
3433 panic("hammer2_chain_indkey_freemap: bad radix");
3442 * Calculate the keybits and highside/lowside of the indirect block the
3443 * caller is creating.
3446 hammer2_chain_indkey_normal(hammer2_chain_t *parent, hammer2_key_t *keyp,
3447 int keybits, hammer2_blockref_t *base, int count)
3449 hammer2_chain_core_t *above;
3450 hammer2_blockref_t *bref;
3451 hammer2_chain_t *chain;
3452 hammer2_key_t key_beg;
3453 hammer2_key_t key_end;
3454 hammer2_key_t key_next;
3463 above = parent->core;
3468 * Calculate the range of keys in the array being careful to skip
3469 * slots which are overridden with a deletion. Once the scan
3470 * completes we will cut the key range in half and shift half the
3471 * range into the new indirect block.
3474 key_end = HAMMER2_MAX_KEY;
3476 spin_lock(&above->cst.spin);
3479 if (++loops == 100000) {
3480 panic("indkey_freemap shit %p %p:%d\n",
3481 parent, base, count);
3483 chain = hammer2_combined_find(parent, base, count,
3484 &cache_index, &key_next,
3485 key_beg, key_end, &bref);
3492 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3493 if (key_next == 0 || key_next > key_end)
3500 * Use the full live (not deleted) element for the scan
3501 * iteration. HAMMER2 does not allow partial replacements.
3503 * XXX should be built into hammer2_combined_find().
3505 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3508 * Expand our calculated key range (key, keybits) to fit
3509 * the scanned key. nkeybits represents the full range
3510 * that we will later cut in half (two halves @ nkeybits - 1).
3513 if (nkeybits < bref->keybits) {
3514 if (bref->keybits > 64) {
3515 kprintf("bad bref chain %p bref %p\n",
3519 nkeybits = bref->keybits;
3521 while (nkeybits < 64 &&
3522 (~(((hammer2_key_t)1 << nkeybits) - 1) &
3523 (key ^ bref->key)) != 0) {
3528 * If the new key range is larger we have to determine
3529 * which side of the new key range the existing keys fall
3530 * under by checking the high bit, then collapsing the
3531 * locount into the hicount or vise-versa.
3533 if (keybits != nkeybits) {
3534 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) {
3545 * The newly scanned key will be in the lower half or the
3546 * upper half of the (new) key range.
3548 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key)
3557 spin_unlock(&above->cst.spin);
3558 bref = NULL; /* now invalid (safety) */
3561 * Adjust keybits to represent half of the full range calculated
3562 * above (radix 63 max)
3567 * Select whichever half contains the most elements. Theoretically
3568 * we can select either side as long as it contains at least one
3569 * element (in order to ensure that a free slot is present to hold
3570 * the indirect block).
3572 if (hammer2_indirect_optimize) {
3574 * Insert node for least number of keys, this will arrange
3575 * the first few blocks of a large file or the first few
3576 * inodes in a directory with fewer indirect blocks when
3579 if (hicount < locount && hicount != 0)
3580 key |= (hammer2_key_t)1 << keybits;
3582 key &= ~(hammer2_key_t)1 << keybits;
3585 * Insert node for most number of keys, best for heavily
3588 if (hicount > locount)
3589 key |= (hammer2_key_t)1 << keybits;
3591 key &= ~(hammer2_key_t)1 << keybits;
3599 * Sets CHAIN_DELETED and CHAIN_MOVED in the chain being deleted and
3600 * set chain->delete_tid. The chain is not actually marked possibly-free
3601 * in the freemap until the deletion is completely flushed out (because
3602 * a flush which doesn't cover the entire deletion is flushing the deleted
3603 * chain as if it were live).
3605 * This function does NOT generate a modification to the parent. It
3606 * would be nearly impossible to figure out which parent to modify anyway.
3607 * Such modifications are handled top-down by the flush code and are
3608 * properly merged using the flush synchronization point.
3610 * The find/get code will properly overload the RBTREE check on top of
3611 * the bref check to detect deleted entries.
3613 * This function is NOT recursive. Any entity already pushed into the
3614 * chain (such as an inode) may still need visibility into its contents,
3615 * as well as the ability to read and modify the contents. For example,
3616 * for an unlinked file which is still open.
3618 * NOTE: This function does NOT set chain->modify_tid, allowing future
3619 * code to distinguish between live and deleted chains by testing
3620 * trans->sync_tid vs chain->modify_tid and chain->delete_tid.
3622 * NOTE: Deletions normally do not occur in the middle of a duplication
3623 * chain but we use a trick for hardlink migration that refactors
3624 * the originating inode without deleting it, so we make no assumptions
3628 hammer2_chain_delete(hammer2_trans_t *trans, hammer2_chain_t *chain, int flags)
3630 KKASSERT(ccms_thread_lock_owned(&chain->core->cst));
3633 * Nothing to do if already marked.
3635 if (chain->flags & HAMMER2_CHAIN_DELETED)
3639 * The setting of DELETED causes finds, lookups, and _next iterations
3640 * to no longer recognize the chain. RB_SCAN()s will still have
3641 * visibility (needed for flush serialization points).
3643 * We need the spinlock on the core whos RBTREE contains chain
3644 * to protect against races.
3646 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
3647 spin_lock(&chain->above->cst.spin);
3649 KKASSERT(trans->sync_tid >= chain->modify_tid);
3650 chain->delete_tid = trans->sync_tid;
3651 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3652 atomic_add_int(&chain->above->live_count, -1);
3653 ++chain->above->generation;
3656 * We must set MOVED along with DELETED for the flush code to
3657 * recognize the operation and properly disconnect the chain
3660 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
3661 hammer2_chain_ref(chain);
3662 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
3664 spin_unlock(&chain->above->cst.spin);
3666 if (flags & HAMMER2_DELETE_WILLDUP)
3667 atomic_set_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
3669 hammer2_chain_setsubmod(trans, chain);
3673 * Called with the core spinlock held to check for freeable layers.
3674 * Used by the flush code. Layers can wind up not being freed due
3675 * to the temporary layer->refs count. This function frees up any
3676 * layers that were missed.
3679 hammer2_chain_layer_check_locked(hammer2_mount_t *hmp,
3680 hammer2_chain_core_t *core)
3682 hammer2_chain_layer_t *layer;
3683 hammer2_chain_layer_t *tmp;
3685 tmp = TAILQ_FIRST(&core->layerq);
3686 while ((layer = tmp) != NULL) {
3687 tmp = TAILQ_NEXT(tmp, entry);
3688 if (layer->refs == 0 && RB_EMPTY(&layer->rbtree)) {
3689 TAILQ_REMOVE(&core->layerq, layer, entry);
3692 spin_unlock(&core->cst.spin);
3693 kfree(layer, hmp->mchain);
3694 spin_lock(&core->cst.spin);
3702 * Returns the index of the nearest element in the blockref array >= elm.
3703 * Returns (count) if no element could be found.
3705 * Sets *key_nextp to the next key for loop purposes but does not modify
3706 * it if the next key would be higher than the current value of *key_nextp.
3707 * Note that *key_nexp can overflow to 0, which should be tested by the
3710 * (*cache_indexp) is a heuristic and can be any value without effecting
3713 * The spin lock on the related chain must be held.
3716 hammer2_base_find(hammer2_chain_t *chain,
3717 hammer2_blockref_t *base, int count,
3718 int *cache_indexp, hammer2_key_t *key_nextp,
3719 hammer2_key_t key_beg, hammer2_key_t key_end)
3721 hammer2_chain_core_t *core = chain->core;
3722 hammer2_blockref_t *scan;
3723 hammer2_key_t scan_end;
3729 KKASSERT(core->flags & HAMMER2_CORE_COUNTEDBREFS);
3730 if (count == 0 || base == NULL)
3734 * Sequential optimization
3738 if (i >= core->live_zero)
3739 i = core->live_zero - 1;
3742 KKASSERT(i < count);
3748 while (i > 0 && (scan->type == 0 || scan->key > key_beg)) {
3755 * Search forwards, stop when we find a scan element which
3756 * encloses the key or until we know that there are no further
3760 if (scan->type != 0) {
3761 if (scan->key > key_beg)
3763 scan_end = scan->key +
3764 ((hammer2_key_t)1 << scan->keybits) - 1;
3765 if (scan_end >= key_beg)
3768 if (i >= core->live_zero)
3775 if (i >= core->live_zero) {
3778 scan_end = scan->key +
3779 ((hammer2_key_t)1 << scan->keybits);
3780 if (scan_end && (*key_nextp > scan_end ||
3782 *key_nextp = scan_end;
3790 * Do a combined search and return the next match either from the blockref
3791 * array or from the in-memory chain. Sets *bresp to the returned bref in
3792 * both cases, or sets it to NULL if the search exhausted. Only returns
3793 * a non-NULL chain if the search matched from the in-memory chain.
3795 * Must be called with above's spinlock held. Spinlock remains held
3796 * through the operation.
3798 * The returned chain is not locked or referenced. Use the returned bref
3799 * to determine if the search exhausted or not.
3801 static hammer2_chain_t *
3802 hammer2_combined_find(hammer2_chain_t *parent,
3803 hammer2_blockref_t *base, int count,
3804 int *cache_indexp, hammer2_key_t *key_nextp,
3805 hammer2_key_t key_beg, hammer2_key_t key_end,
3806 hammer2_blockref_t **bresp)
3808 hammer2_blockref_t *bref;
3809 hammer2_chain_t *chain;
3812 *key_nextp = key_end + 1;
3813 i = hammer2_base_find(parent, base, count, cache_indexp,
3814 key_nextp, key_beg, key_end);
3815 chain = hammer2_chain_find(parent, key_nextp, key_beg, key_end);
3820 if (i == count && chain == NULL) {
3822 return(chain); /* NULL */
3826 * Only chain matched
3829 bref = &chain->bref;
3834 * Only blockref matched.
3836 if (chain == NULL) {
3842 * Both in-memory and blockref match.
3844 * If they are both flush with the left hand side select the chain.
3845 * If their starts match select the chain.
3846 * Otherwise the nearer element wins.
3848 if (chain->bref.key <= key_beg && base[i].key <= key_beg) {
3849 bref = &chain->bref;
3852 if (chain->bref.key <= base[i].key) {
3853 bref = &chain->bref;
3861 * If the bref is out of bounds we've exhausted our search.
3864 if (bref->key > key_end) {
3874 * Locate the specified block array element and delete it. The element
3877 * The spin lock on the related chain must be held.
3879 * NOTE: live_count was adjusted when the chain was deleted, so it does not
3880 * need to be adjusted when we commit the media change.
3883 hammer2_base_delete(hammer2_chain_t *chain,
3884 hammer2_blockref_t *base, int count,
3885 int *cache_indexp, hammer2_chain_t *child)
3887 hammer2_blockref_t *elm = &child->bref;
3888 hammer2_chain_core_t *core = chain->core;
3889 hammer2_key_t key_next;
3893 * Delete element. Expect the element to exist.
3895 * XXX see caller, flush code not yet sophisticated enough to prevent
3896 * re-flushed in some cases.
3898 key_next = 0; /* max range */
3899 i = hammer2_base_find(chain, base, count, cache_indexp,
3900 &key_next, elm->key, elm->key);
3901 if (i == count || base[i].type == 0 ||
3902 base[i].key != elm->key || base[i].keybits != elm->keybits) {
3903 panic("delete base %p element not found at %d/%d elm %p\n",
3904 base, i, count, elm);
3907 bzero(&base[i], sizeof(*base));
3908 if (core->live_zero == i + 1) {
3909 while (--i >= 0 && base[i].type == 0)
3911 core->live_zero = i + 1;
3916 * Insert the specified element. The block array must not already have the
3917 * element and must have space available for the insertion.
3919 * The spin lock on the related chain must be held.
3921 * NOTE: live_count was adjusted when the chain was deleted, so it does not
3922 * need to be adjusted when we commit the media change.
3925 hammer2_base_insert(hammer2_chain_t *parent,
3926 hammer2_blockref_t *base, int count,
3927 int *cache_indexp, hammer2_chain_t *child)
3929 hammer2_blockref_t *elm = &child->bref;
3930 hammer2_chain_core_t *core = parent->core;
3931 hammer2_key_t key_next;
3940 * Insert new element. Expect the element to not already exist
3941 * unless we are replacing it.
3943 * XXX see caller, flush code not yet sophisticated enough to prevent
3944 * re-flushed in some cases.
3946 key_next = 0; /* max range */
3947 i = hammer2_base_find(parent, base, count, cache_indexp,
3948 &key_next, elm->key, elm->key);
3951 * Shortcut fill optimization, typical ordered insertion(s) may not
3954 KKASSERT(i >= 0 && i <= count);
3956 if (i == count && core->live_zero < count) {
3957 i = core->live_zero++;
3962 xkey = elm->key + ((hammer2_key_t)1 << elm->keybits) - 1;
3963 if (i != count && (base[i].key < elm->key || xkey >= base[i].key)) {
3964 panic("insert base %p overlapping elements at %d elm %p\n",
3969 * Try to find an empty slot before or after.
3973 while (j > 0 || k < count) {
3975 if (j >= 0 && base[j].type == 0) {
3979 bcopy(&base[j+1], &base[j],
3980 (i - j - 1) * sizeof(*base));
3986 if (k < count && base[k].type == 0) {
3987 bcopy(&base[i], &base[i+1],
3988 (k - i) * sizeof(hammer2_blockref_t));
3990 if (core->live_zero <= k)
3991 core->live_zero = k + 1;
3996 panic("hammer2_base_insert: no room!");
4003 for (l = 0; l < count; ++l) {
4005 key_next = base[l].key +
4006 ((hammer2_key_t)1 << base[l].keybits) - 1;
4010 while (++l < count) {
4012 if (base[l].key <= key_next)
4013 panic("base_insert %d %d,%d,%d fail %p:%d", u, i, j, k, base, l);
4014 key_next = base[l].key +
4015 ((hammer2_key_t)1 << base[l].keybits) - 1;
4025 * Sort the blockref array for the chain. Used by the flush code to
4026 * sort the blockref[] array.
4028 * The chain must be exclusively locked AND spin-locked.
4030 typedef hammer2_blockref_t *hammer2_blockref_p;
4034 hammer2_base_sort_callback(const void *v1, const void *v2)
4036 hammer2_blockref_p bref1 = *(const hammer2_blockref_p *)v1;
4037 hammer2_blockref_p bref2 = *(const hammer2_blockref_p *)v2;
4040 * Make sure empty elements are placed at the end of the array
4042 if (bref1->type == 0) {
4043 if (bref2->type == 0)
4046 } else if (bref2->type == 0) {
4053 if (bref1->key < bref2->key)
4055 if (bref1->key > bref2->key)
4061 hammer2_base_sort(hammer2_chain_t *chain)
4063 hammer2_blockref_t *base;
4066 switch(chain->bref.type) {
4067 case HAMMER2_BREF_TYPE_INODE:
4069 * Special shortcut for embedded data returns the inode
4070 * itself. Callers must detect this condition and access
4071 * the embedded data (the strategy code does this for us).
4073 * This is only applicable to regular files and softlinks.
4075 if (chain->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA)
4077 base = &chain->data->ipdata.u.blockset.blockref[0];
4078 count = HAMMER2_SET_COUNT;
4080 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4081 case HAMMER2_BREF_TYPE_INDIRECT:
4083 * Optimize indirect blocks in the INITIAL state to avoid
4086 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) == 0);
4087 base = &chain->data->npdata[0];
4088 count = chain->bytes / sizeof(hammer2_blockref_t);
4090 case HAMMER2_BREF_TYPE_VOLUME:
4091 base = &chain->hmp->voldata.sroot_blockset.blockref[0];
4092 count = HAMMER2_SET_COUNT;
4094 case HAMMER2_BREF_TYPE_FREEMAP:
4095 base = &chain->hmp->voldata.freemap_blockset.blockref[0];
4096 count = HAMMER2_SET_COUNT;
4099 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
4101 base = NULL; /* safety */
4102 count = 0; /* safety */
4104 kqsort(base, count, sizeof(*base), hammer2_base_sort_callback);
4110 * Chain memory management
4113 hammer2_chain_wait(hammer2_chain_t *chain)
4115 tsleep(chain, 0, "chnflw", 1);
4119 * Manage excessive memory resource use for chain and related
4123 hammer2_chain_memory_wait(hammer2_pfsmount_t *pmp)
4126 while (pmp->inmem_chains > desiredvnodes / 10 &&
4127 pmp->inmem_chains > pmp->mp->mnt_nvnodelistsize * 2) {
4129 speedup_syncer(pmp->mp);
4130 pmp->inmem_waiting = 1;
4131 tsleep(&pmp->inmem_waiting, 0, "chnmem", hz);
4135 if (pmp->inmem_chains > desiredvnodes / 10 &&
4136 pmp->inmem_chains > pmp->mp->mnt_nvnodelistsize * 7 / 4) {
4137 speedup_syncer(pmp->mp);
4143 hammer2_chain_memory_wakeup(hammer2_pfsmount_t *pmp)
4145 if (pmp->inmem_waiting &&
4146 (pmp->inmem_chains <= desiredvnodes / 10 ||
4147 pmp->inmem_chains <= pmp->mp->mnt_nvnodelistsize * 2)) {
4149 pmp->inmem_waiting = 0;
4150 wakeup(&pmp->inmem_waiting);
4156 adjreadcounter(hammer2_blockref_t *bref, size_t bytes)
4160 switch(bref->type) {
4161 case HAMMER2_BREF_TYPE_DATA:
4162 counterp = &hammer2_iod_file_read;
4164 case HAMMER2_BREF_TYPE_INODE:
4165 counterp = &hammer2_iod_meta_read;
4167 case HAMMER2_BREF_TYPE_INDIRECT:
4168 counterp = &hammer2_iod_indr_read;
4170 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4171 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
4172 counterp = &hammer2_iod_fmap_read;
4175 counterp = &hammer2_iod_volu_read;