2 * Copyright (c) 2011-2013 The DragonFly Project. All rights reserved.
4 * This code is derived from software contributed to The DragonFly Project
5 * by Matthew Dillon <dillon@dragonflybsd.org>
6 * by Venkatesh Srinivas <vsrinivas@dragonflybsd.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * This subsystem implements most of the core support functions for
37 * the hammer2_chain structure.
39 * Chains are the in-memory version on media objects (volume header, inodes,
40 * indirect blocks, data blocks, etc). Chains represent a portion of the
43 * A chain is topologically stable once it has been inserted into the
44 * in-memory topology. Modifications which copy, move, or resize the chain
45 * are handled via the DELETE-DUPLICATE mechanic where the original chain
46 * stays intact but is marked deleted and a new chain is allocated which
47 * shares the old chain's children.
49 * This sharing is handled via the hammer2_chain_core structure.
51 * The DELETE-DUPLICATE mechanism allows the same topological level to contain
52 * many overloadings. However, our RBTREE mechanics require that there be
53 * no overlaps so we accomplish the overloading by moving conflicting chains
54 * with smaller or equal radii into a sub-RBTREE under the chain being
57 * DELETE-DUPLICATE is also used when a modification to a chain crosses a
58 * flush synchronization boundary, allowing the flush code to continue flushing
59 * the older version of the topology and not be disrupted by new frontend
64 * All lookup and iterate operations and most modifications are done on the
65 * live view. During flushes lookups are not normally done and modifications
66 * may be run on the flush view. However, flushes often needs to allocate
67 * blocks and the freemap_alloc/free code issues lookups. This code is
68 * special cased to use the live view when called from a flush.
70 * General chain lookup/iteration functions are NOT aware of the flush view,
71 * they only know about live views.
73 #include <sys/cdefs.h>
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/types.h>
78 #include <sys/kern_syscall.h>
83 static int hammer2_indirect_optimize; /* XXX SYSCTL */
85 static hammer2_chain_t *hammer2_chain_create_indirect(
86 hammer2_trans_t *trans, hammer2_chain_t *parent,
87 hammer2_key_t key, int keybits, int for_type, int *errorp);
88 static void hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop);
89 static void adjreadcounter(hammer2_blockref_t *bref, size_t bytes);
90 static hammer2_chain_t *hammer2_combined_find(
91 hammer2_chain_t *parent,
92 hammer2_blockref_t *base, int count,
93 int *cache_indexp, hammer2_key_t *key_nextp,
94 hammer2_key_t key_beg, hammer2_key_t key_end,
95 hammer2_blockref_t **bresp);
98 * Basic RBTree for chains. Chains cannot overlap within any given
99 * core->rbtree without recursing through chain->rbtree. We effectively
100 * guarantee this by checking the full range rather than just the first
101 * key element. By matching on the full range callers can detect when
102 * recursrion through chain->rbtree is needed.
104 * NOTE: This also means the a delete-duplicate on the same key will
105 * overload by placing the deleted element in the new element's
106 * chain->rbtree (when doing a direct replacement).
108 RB_GENERATE(hammer2_chain_tree, hammer2_chain, rbnode, hammer2_chain_cmp);
111 hammer2_chain_cmp(hammer2_chain_t *chain1, hammer2_chain_t *chain2)
113 hammer2_key_t c1_beg;
114 hammer2_key_t c1_end;
115 hammer2_key_t c2_beg;
116 hammer2_key_t c2_end;
118 c1_beg = chain1->bref.key;
119 c1_end = c1_beg + ((hammer2_key_t)1 << chain1->bref.keybits) - 1;
120 c2_beg = chain2->bref.key;
121 c2_end = c2_beg + ((hammer2_key_t)1 << chain2->bref.keybits) - 1;
123 if (c1_end < c2_beg) /* fully to the left */
125 if (c1_beg > c2_end) /* fully to the right */
127 return(0); /* overlap (must not cross edge boundary) */
132 hammer2_isclusterable(hammer2_chain_t *chain)
134 if (hammer2_cluster_enable) {
135 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
136 chain->bref.type == HAMMER2_BREF_TYPE_INODE ||
137 chain->bref.type == HAMMER2_BREF_TYPE_DATA) {
145 * Recursively set the update_hi flag up to the root starting at chain's
146 * parent->core. update_hi is not set in chain's core.
148 * This controls top-down visibility for flushes. The child has just one
149 * 'above' core, but the core itself can be multi-homed with parents iterated
152 * This function is not used during a flush (except when the flush is
153 * allocating which requires the live tree). The flush keeps track of its
156 * XXX needs to be optimized to use roll-up TIDs. update_hi is only really
157 * compared against bref.mirror_tid which itself is only updated by a flush.
160 hammer2_chain_setsubmod(hammer2_trans_t *trans, hammer2_chain_t *chain)
162 hammer2_chain_core_t *above;
166 (HAMMER2_TRANS_ISFLUSH | HAMMER2_TRANS_ISALLOCATING)) ==
167 HAMMER2_TRANS_ISFLUSH) {
172 while ((above = chain->above) != NULL) {
173 spin_lock(&above->cst.spin);
175 if (above->update_hi < trans->sync_tid)
176 above->update_hi = trans->sync_tid;
177 chain = TAILQ_LAST(&above->ownerq, h2_core_list);
179 TAILQ_FOREACH_REVERSE(chain, &above->ownerq,
180 h2_core_list, core_entry) {
181 if (trans->sync_tid >= chain->modify_tid &&
182 trans->sync_tid <= chain->delete_tid) {
187 spin_unlock(&above->cst.spin);
192 * Allocate a new disconnected chain element representing the specified
193 * bref. chain->refs is set to 1 and the passed bref is copied to
194 * chain->bref. chain->bytes is derived from the bref.
196 * chain->core is NOT allocated and the media data and bp pointers are left
197 * NULL. The caller must call chain_core_alloc() to allocate or associate
198 * a core with the chain.
200 * NOTE: Returns a referenced but unlocked (because there is no core) chain.
203 hammer2_chain_alloc(hammer2_mount_t *hmp, hammer2_pfsmount_t *pmp,
204 hammer2_trans_t *trans, hammer2_blockref_t *bref)
206 hammer2_chain_t *chain;
207 u_int bytes = 1U << (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
210 * Construct the appropriate system structure.
213 case HAMMER2_BREF_TYPE_INODE:
214 case HAMMER2_BREF_TYPE_INDIRECT:
215 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
216 case HAMMER2_BREF_TYPE_DATA:
217 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
219 * Chain's are really only associated with the hmp but we
220 * maintain a pmp association for per-mount memory tracking
221 * purposes. The pmp can be NULL.
223 chain = kmalloc(sizeof(*chain), hmp->mchain, M_WAITOK | M_ZERO);
226 atomic_add_long(&pmp->inmem_chains, 1);
229 case HAMMER2_BREF_TYPE_VOLUME:
230 case HAMMER2_BREF_TYPE_FREEMAP:
232 panic("hammer2_chain_alloc volume type illegal for op");
235 panic("hammer2_chain_alloc: unrecognized blockref type: %d",
241 chain->bytes = bytes;
243 chain->flags = HAMMER2_CHAIN_ALLOCATED;
244 chain->delete_tid = HAMMER2_MAX_TID;
247 * Set modify_tid if a transaction is creating the chain. When
248 * loading a chain from backing store trans is passed as NULL and
249 * modify_tid is left set to 0.
252 chain->modify_tid = trans->sync_tid;
258 * Associate an existing core with the chain or allocate a new core.
260 * The core is not locked. No additional refs on the chain are made.
261 * (trans) must not be NULL if (core) is not NULL.
263 * When chains are delete-duplicated during flushes we insert nchain on
264 * the ownerq after ochain instead of at the end in order to give the
265 * drop code visibility in the correct order, otherwise drops can be missed.
268 hammer2_chain_core_alloc(hammer2_trans_t *trans,
269 hammer2_chain_t *nchain, hammer2_chain_t *ochain)
271 hammer2_chain_core_t *core;
273 KKASSERT(nchain->core == NULL);
275 if (ochain == NULL) {
277 * Fresh core under nchain (no multi-homing of ochain's
280 core = kmalloc(sizeof(*core), nchain->hmp->mchain,
282 TAILQ_INIT(&core->layerq);
283 TAILQ_INIT(&core->ownerq);
287 core->update_hi = trans->sync_tid;
289 core->update_hi = nchain->bref.mirror_tid;
291 ccms_cst_init(&core->cst, nchain);
292 TAILQ_INSERT_TAIL(&core->ownerq, nchain, core_entry);
295 * Propagate the PFSROOT flag which we set on all subdirs
296 * under the super-root.
298 atomic_set_int(&nchain->flags,
299 ochain->flags & HAMMER2_CHAIN_PFSROOT);
302 * Duplicating ochain -> nchain. Set the DUPLICATED flag on
303 * ochain if nchain is not a snapshot.
305 * It is possible for the DUPLICATED flag to already be
306 * set when called via a flush operation because flush
307 * operations may have to work on elements with delete_tid's
308 * beyond the flush sync_tid. In this situation we must
309 * ensure that nchain is placed just after ochain in the
310 * ownerq and that the DUPLICATED flag is set on nchain so
311 * 'live' operations skip past it to the correct chain.
313 * The flusher understands the blockref synchronization state
314 * for any stale chains by observing bref.mirror_tid, which
315 * delete-duplicate replicates.
317 * WARNING! However, the case is disallowed when the flusher
318 * is allocating freemap space because this entails
319 * more than just adjusting a block table.
321 if (ochain->flags & HAMMER2_CHAIN_DUPLICATED) {
322 KKASSERT((trans->flags &
323 (HAMMER2_TRANS_ISFLUSH |
324 HAMMER2_TRANS_ISALLOCATING)) ==
325 HAMMER2_TRANS_ISFLUSH);
326 atomic_set_int(&nchain->flags,
327 HAMMER2_CHAIN_DUPLICATED);
329 if ((nchain->flags & HAMMER2_CHAIN_SNAPSHOT) == 0) {
330 atomic_set_int(&ochain->flags,
331 HAMMER2_CHAIN_DUPLICATED);
334 atomic_add_int(&core->sharecnt, 1);
336 spin_lock(&core->cst.spin);
340 if (core->update_hi < trans->sync_tid)
341 core->update_hi = trans->sync_tid;
345 * Maintain ordering for refactor test so we don't skip over
346 * a snapshot. Also, during flushes, delete-duplications
347 * for block-table updates can occur on blocks already
348 * deleted (delete-duplicated by a later transaction). We
349 * must insert nchain after ochain but before the later
350 * transaction's copy.
352 TAILQ_INSERT_AFTER(&core->ownerq, ochain, nchain, core_entry);
354 spin_unlock(&core->cst.spin);
359 * Add a reference to a chain element, preventing its destruction.
362 hammer2_chain_ref(hammer2_chain_t *chain)
364 atomic_add_int(&chain->refs, 1);
368 * Insert the chain in the core rbtree at the first layer
369 * which accepts it (for now we don't sort layers by the transaction tid)
371 #define HAMMER2_CHAIN_INSERT_SPIN 0x0001
372 #define HAMMER2_CHAIN_INSERT_LIVE 0x0002
373 #define HAMMER2_CHAIN_INSERT_RACE 0x0004
377 hammer2_chain_insert(hammer2_chain_core_t *above, hammer2_chain_layer_t *layer,
378 hammer2_chain_t *chain, int flags)
380 hammer2_chain_t *xchain;
381 hammer2_chain_layer_t *nlayer;
383 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
384 spin_lock(&above->cst.spin);
385 chain->above = above;
388 * Special case, place chain in a more recent layer than the specified
392 nlayer = TAILQ_PREV(layer, h2_layer_list, entry);
393 if (nlayer && RB_INSERT(hammer2_chain_tree,
394 &nlayer->rbtree, chain) == NULL) {
399 spin_unlock(&above->cst.spin);
400 KKASSERT((flags & HAMMER2_CHAIN_INSERT_LIVE) == 0);
401 nlayer = kmalloc(sizeof(*nlayer), chain->hmp->mchain,
403 RB_INIT(&nlayer->rbtree);
404 nlayer->good = 0xABCD;
405 spin_lock(&above->cst.spin);
407 TAILQ_INSERT_BEFORE(layer, nlayer, entry);
408 RB_INSERT(hammer2_chain_tree, &nlayer->rbtree, chain);
413 layer = TAILQ_FIRST(&above->layerq);
420 (xchain = RB_INSERT(hammer2_chain_tree,
421 &layer->rbtree, chain)) != NULL) {
423 * Either no layers have been allocated or the insertion
424 * failed. This is fatal if the conflicted xchain is not
425 * flagged as deleted. Caller may or may allow the failure.
427 if ((flags & HAMMER2_CHAIN_INSERT_RACE) &&
428 xchain && (xchain->flags & HAMMER2_CHAIN_DELETED) == 0) {
430 chain->inlayer = NULL;
431 kprintf("insertion race against %p\n", xchain);
436 * Allocate a new layer to resolve the issue.
438 spin_unlock(&above->cst.spin);
439 layer = kmalloc(sizeof(*layer), chain->hmp->mchain,
441 RB_INIT(&layer->rbtree);
442 layer->good = 0xABCD;
443 spin_lock(&above->cst.spin);
444 TAILQ_INSERT_HEAD(&above->layerq, layer, entry);
445 RB_INSERT(hammer2_chain_tree, &layer->rbtree, chain);
448 chain->inlayer = layer;
449 ++above->chain_count;
452 if ((flags & HAMMER2_CHAIN_INSERT_LIVE) &&
453 (chain->flags & HAMMER2_CHAIN_DELETED) == 0) {
454 atomic_add_int(&above->live_count, 1);
456 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
458 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
459 spin_unlock(&above->cst.spin);
463 * Drop the caller's reference to the chain. When the ref count drops to
464 * zero this function will disassociate the chain from its parent and
465 * deallocate it, then recursely drop the parent using the implied ref
466 * from the chain's chain->parent.
468 * WARNING! Just because we are able to deallocate a chain doesn't mean
469 * that chain->core->rbtree is empty. There can still be a sharecnt
470 * on chain->core and RBTREE entries that refer to different parents.
472 static hammer2_chain_t *hammer2_chain_lastdrop(hammer2_chain_t *chain,
473 struct h2_core_list *delayq);
476 hammer2_chain_drop(hammer2_chain_t *chain)
478 struct h2_core_list delayq;
479 hammer2_chain_t *scan;
483 if (hammer2_debug & 0x200000)
486 if (chain->flags & HAMMER2_CHAIN_MOVED)
488 if (chain->flags & HAMMER2_CHAIN_MODIFIED)
490 KKASSERT(chain->refs > need);
500 chain = hammer2_chain_lastdrop(chain, &delayq);
502 if (atomic_cmpset_int(&chain->refs, refs, refs - 1))
504 /* retry the same chain */
508 * When we've exhausted lastdrop chaining pull off of delayq.
509 * chains on delayq are dead but are used to placehold other
510 * chains which we added a ref to for the purpose of dropping.
513 hammer2_mount_t *hmp;
515 if ((scan = TAILQ_FIRST(&delayq)) != NULL) {
516 chain = (void *)scan->data;
517 TAILQ_REMOVE(&delayq, scan, core_entry);
518 scan->flags &= ~HAMMER2_CHAIN_ALLOCATED;
521 kfree(scan, hmp->mchain);
528 * Safe handling of the 1->0 transition on chain. Returns a chain for
529 * recursive drop or NULL, possibly returning the same chain if the atomic
532 * Whem two chains need to be recursively dropped we use the chain
533 * we would otherwise free to placehold the additional chain. It's a bit
534 * convoluted but we can't just recurse without potentially blowing out
537 * The cst spinlock is allowed nest child-to-parent (not parent-to-child).
541 hammer2_chain_lastdrop(hammer2_chain_t *chain, struct h2_core_list *delayq)
543 hammer2_pfsmount_t *pmp;
544 hammer2_mount_t *hmp;
545 hammer2_chain_core_t *above;
546 hammer2_chain_core_t *core;
547 hammer2_chain_layer_t *layer;
548 hammer2_chain_t *rdrop1;
549 hammer2_chain_t *rdrop2;
552 * Spinlock the core and check to see if it is empty. If it is
553 * not empty we leave chain intact with refs == 0. The elements
554 * in core->rbtree are associated with other chains contemporary
555 * with ours but not with our chain directly.
557 if ((core = chain->core) != NULL) {
558 spin_lock(&core->cst.spin);
561 * We can't free chains with children because there might
562 * be a flush dependency.
564 * NOTE: We return (chain) on failure to retry.
566 if (core->chain_count) {
567 if (atomic_cmpset_int(&chain->refs, 1, 0))
568 chain = NULL; /* success */
569 spin_unlock(&core->cst.spin);
572 /* no chains left under us */
575 * Because various parts of the code, including the inode
576 * structure, might be holding a stale chain and need to
577 * iterate to a non-stale sibling, we cannot remove siblings
578 * unless they are at the head of chain.
580 * We can't free a live chain unless it is a the head
581 * of its ownerq. If we were to then the go-to chain
582 * would revert to the prior deleted chain.
584 if (TAILQ_FIRST(&core->ownerq) != chain) {
585 if (atomic_cmpset_int(&chain->refs, 1, 0))
586 chain = NULL; /* success */
587 spin_unlock(&core->cst.spin);
593 * chain->core has no children left so no accessors can get to our
594 * chain from there. Now we have to lock the above core to interlock
595 * remaining possible accessors that might bump chain's refs before
596 * we can safely drop chain's refs with intent to free the chain.
599 pmp = chain->pmp; /* can be NULL */
605 * Spinlock the parent and try to drop the last ref on chain.
606 * On success remove chain from its parent, otherwise return NULL.
608 * (normal core locks are top-down recursive but we define core
609 * spinlocks as bottom-up recursive, so this is safe).
611 if ((above = chain->above) != NULL) {
612 spin_lock(&above->cst.spin);
613 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) {
614 /* 1->0 transition failed */
615 spin_unlock(&above->cst.spin);
617 spin_unlock(&core->cst.spin);
618 return(chain); /* retry */
622 * 1->0 transition successful, remove chain from its
623 * above core. Track layer for removal/freeing.
625 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
626 layer = chain->inlayer;
627 RB_REMOVE(hammer2_chain_tree, &layer->rbtree, chain);
628 --above->chain_count;
629 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
631 chain->inlayer = NULL;
633 if (RB_EMPTY(&layer->rbtree) && layer->refs == 0) {
634 TAILQ_REMOVE(&above->layerq, layer, entry);
640 * If our chain was the last chain in the parent's core the
641 * core is now empty and its parents might now be droppable.
642 * Try to drop the first multi-homed parent by gaining a
643 * ref on it here and then dropping it below.
645 if (above->chain_count == 0) {
646 rdrop1 = TAILQ_FIRST(&above->ownerq);
648 atomic_cmpset_int(&rdrop1->refs, 0, 1) == 0) {
652 spin_unlock(&above->cst.spin);
653 above = NULL; /* safety */
657 * Successful 1->0 transition and the chain can be destroyed now.
659 * We still have the core spinlock (if core is non-NULL), and core's
660 * chain_count is 0. The above spinlock is gone.
662 * Remove chain from ownerq. Once core has no more owners (and no
663 * children which is already the case) we can destroy core.
665 * If core has more owners we may be able to continue a bottom-up
666 * drop with our next sibling.
671 TAILQ_REMOVE(&core->ownerq, chain, core_entry);
672 rdrop2 = TAILQ_FIRST(&core->ownerq);
673 if (rdrop2 && atomic_cmpset_int(&rdrop2->refs, 0, 1) == 0)
675 spin_unlock(&core->cst.spin);
678 * We can do the final 1->0 transition with an atomic op
679 * after releasing core's spinlock.
681 if (atomic_fetchadd_int(&core->sharecnt, -1) == 1) {
683 * On the 1->0 transition of core we can destroy
684 * it. Any remaining layers should no longer be
685 * referenced or visibile to other threads.
687 KKASSERT(TAILQ_EMPTY(&core->ownerq));
689 layer->good = 0xEF00;
690 kfree(layer, hmp->mchain);
692 while ((layer = TAILQ_FIRST(&core->layerq)) != NULL) {
693 KKASSERT(layer->refs == 0 &&
694 RB_EMPTY(&layer->rbtree));
695 TAILQ_REMOVE(&core->layerq, layer, entry);
696 layer->good = 0xEF01;
697 kfree(layer, hmp->mchain);
700 KKASSERT(core->cst.count == 0);
701 KKASSERT(core->cst.upgrade == 0);
703 kfree(core, hmp->mchain);
705 core = NULL; /* safety */
709 * All spin locks are gone, finish freeing stuff.
711 KKASSERT((chain->flags & (HAMMER2_CHAIN_MOVED |
712 HAMMER2_CHAIN_MODIFIED)) == 0);
713 hammer2_chain_drop_data(chain, 1);
715 KKASSERT(chain->dio == NULL);
718 * Free saved empty layer and return chained drop.
721 layer->good = 0xEF02;
722 kfree(layer, hmp->mchain);
726 * Once chain resources are gone we can use the now dead chain
727 * structure to placehold what might otherwise require a recursive
728 * drop, because we have potentially two things to drop and can only
729 * return one directly.
731 if (rdrop1 && rdrop2) {
732 KKASSERT(chain->flags & HAMMER2_CHAIN_ALLOCATED);
733 chain->data = (void *)rdrop1;
734 TAILQ_INSERT_TAIL(delayq, chain, core_entry);
736 } else if (chain->flags & HAMMER2_CHAIN_ALLOCATED) {
737 chain->flags &= ~HAMMER2_CHAIN_ALLOCATED;
739 kfree(chain, hmp->mchain);
742 atomic_add_long(&pmp->inmem_chains, -1);
743 hammer2_chain_memory_wakeup(pmp);
747 * Either or both can be NULL. We already handled the case where
748 * both might not have been NULL.
757 * On either last lock release or last drop
760 hammer2_chain_drop_data(hammer2_chain_t *chain, int lastdrop)
762 hammer2_mount_t *hmp = chain->hmp;
764 switch(chain->bref.type) {
765 case HAMMER2_BREF_TYPE_VOLUME:
766 case HAMMER2_BREF_TYPE_FREEMAP:
770 case HAMMER2_BREF_TYPE_INODE:
772 kfree(chain->data, hmp->mchain);
776 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
778 kfree(chain->data, hmp->mchain);
783 KKASSERT(chain->data == NULL);
789 * Ref and lock a chain element, acquiring its data with I/O if necessary,
790 * and specify how you would like the data to be resolved.
792 * Returns 0 on success or an error code if the data could not be acquired.
793 * The chain element is locked on return regardless of whether an error
796 * The lock is allowed to recurse, multiple locking ops will aggregate
797 * the requested resolve types. Once data is assigned it will not be
798 * removed until the last unlock.
800 * HAMMER2_RESOLVE_NEVER - Do not resolve the data element.
801 * (typically used to avoid device/logical buffer
804 * HAMMER2_RESOLVE_MAYBE - Do not resolve data elements for chains in
805 * the INITIAL-create state (indirect blocks only).
807 * Do not resolve data elements for DATA chains.
808 * (typically used to avoid device/logical buffer
811 * HAMMER2_RESOLVE_ALWAYS- Always resolve the data element.
813 * HAMMER2_RESOLVE_SHARED- (flag) The chain is locked shared, otherwise
814 * it will be locked exclusive.
816 * NOTE: Embedded elements (volume header, inodes) are always resolved
819 * NOTE: Specifying HAMMER2_RESOLVE_ALWAYS on a newly-created non-embedded
820 * element will instantiate and zero its buffer, and flush it on
823 * NOTE: (data) elements are normally locked RESOLVE_NEVER or RESOLVE_MAYBE
824 * so as not to instantiate a device buffer, which could alias against
825 * a logical file buffer. However, if ALWAYS is specified the
826 * device buffer will be instantiated anyway.
828 * WARNING! If data must be fetched a shared lock will temporarily be
829 * upgraded to exclusive. However, a deadlock can occur if
830 * the caller owns more than one shared lock.
833 hammer2_chain_lock(hammer2_chain_t *chain, int how)
835 hammer2_mount_t *hmp;
836 hammer2_chain_core_t *core;
837 hammer2_blockref_t *bref;
843 * Ref and lock the element. Recursive locks are allowed.
845 if ((how & HAMMER2_RESOLVE_NOREF) == 0)
846 hammer2_chain_ref(chain);
847 atomic_add_int(&chain->lockcnt, 1);
850 KKASSERT(hmp != NULL);
853 * Get the appropriate lock.
856 if (how & HAMMER2_RESOLVE_SHARED)
857 ccms_thread_lock(&core->cst, CCMS_STATE_SHARED);
859 ccms_thread_lock(&core->cst, CCMS_STATE_EXCLUSIVE);
862 * If we already have a valid data pointer no further action is
869 * Do we have to resolve the data?
871 switch(how & HAMMER2_RESOLVE_MASK) {
872 case HAMMER2_RESOLVE_NEVER:
874 case HAMMER2_RESOLVE_MAYBE:
875 if (chain->flags & HAMMER2_CHAIN_INITIAL)
877 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA)
880 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE)
883 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF)
886 case HAMMER2_RESOLVE_ALWAYS:
891 * Upgrade to an exclusive lock so we can safely manipulate the
892 * buffer cache. If another thread got to it before us we
895 ostate = ccms_thread_lock_upgrade(&core->cst);
897 ccms_thread_lock_downgrade(&core->cst, ostate);
902 * We must resolve to a device buffer, either by issuing I/O or
903 * by creating a zero-fill element. We do not mark the buffer
904 * dirty when creating a zero-fill element (the hammer2_chain_modify()
905 * API must still be used to do that).
907 * The device buffer is variable-sized in powers of 2 down
908 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
909 * chunk always contains buffers of the same size. (XXX)
911 * The minimum physical IO size may be larger than the variable
917 * The getblk() optimization can only be used on newly created
918 * elements if the physical block size matches the request.
920 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
921 error = hammer2_io_new(hmp, bref->data_off, chain->bytes,
924 error = hammer2_io_bread(hmp, bref->data_off, chain->bytes,
926 adjreadcounter(&chain->bref, chain->bytes);
930 kprintf("hammer2_chain_lock: I/O error %016jx: %d\n",
931 (intmax_t)bref->data_off, error);
932 hammer2_io_bqrelse(&chain->dio);
933 ccms_thread_lock_downgrade(&core->cst, ostate);
938 * We can clear the INITIAL state now, we've resolved the buffer
939 * to zeros and marked it dirty with hammer2_io_new().
941 bdata = hammer2_io_data(chain->dio, chain->bref.data_off);
942 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
943 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
947 * Setup the data pointer, either pointing it to an embedded data
948 * structure and copying the data from the buffer, or pointing it
951 * The buffer is not retained when copying to an embedded data
952 * structure in order to avoid potential deadlocks or recursions
953 * on the same physical buffer.
955 switch (bref->type) {
956 case HAMMER2_BREF_TYPE_VOLUME:
957 case HAMMER2_BREF_TYPE_FREEMAP:
959 * Copy data from bp to embedded buffer
961 panic("hammer2_chain_lock: called on unresolved volume header");
963 case HAMMER2_BREF_TYPE_INODE:
965 * Copy data from dio to embedded buffer, do not retain the
968 KKASSERT(chain->bytes == sizeof(chain->data->ipdata));
969 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
970 chain->data = kmalloc(sizeof(chain->data->ipdata),
971 hmp->mchain, M_WAITOK | M_ZERO);
972 bcopy(bdata, &chain->data->ipdata, chain->bytes);
973 hammer2_io_bqrelse(&chain->dio);
975 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
976 KKASSERT(chain->bytes == sizeof(chain->data->bmdata));
977 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
978 chain->data = kmalloc(sizeof(chain->data->bmdata),
979 hmp->mchain, M_WAITOK | M_ZERO);
980 bcopy(bdata, &chain->data->bmdata, chain->bytes);
981 hammer2_io_bqrelse(&chain->dio);
983 case HAMMER2_BREF_TYPE_INDIRECT:
984 case HAMMER2_BREF_TYPE_DATA:
985 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
988 * Point data at the device buffer and leave bp intact.
990 chain->data = (void *)bdata;
993 ccms_thread_lock_downgrade(&core->cst, ostate);
998 * This basically calls hammer2_io_breadcb() but does some pre-processing
999 * of the chain first to handle certain cases.
1002 hammer2_chain_load_async(hammer2_chain_t *chain,
1003 void (*callback)(hammer2_io_t *dio,
1004 hammer2_chain_t *chain,
1005 void *arg_p, off_t arg_o),
1006 void *arg_p, off_t arg_o)
1008 hammer2_mount_t *hmp;
1009 struct hammer2_io *dio;
1010 hammer2_blockref_t *bref;
1014 callback(NULL, chain, arg_p, arg_o);
1019 * We must resolve to a device buffer, either by issuing I/O or
1020 * by creating a zero-fill element. We do not mark the buffer
1021 * dirty when creating a zero-fill element (the hammer2_chain_modify()
1022 * API must still be used to do that).
1024 * The device buffer is variable-sized in powers of 2 down
1025 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
1026 * chunk always contains buffers of the same size. (XXX)
1028 * The minimum physical IO size may be larger than the variable
1031 bref = &chain->bref;
1035 * The getblk() optimization can only be used on newly created
1036 * elements if the physical block size matches the request.
1038 if ((chain->flags & HAMMER2_CHAIN_INITIAL) &&
1039 chain->bytes == hammer2_devblksize(chain->bytes)) {
1040 error = hammer2_io_new(hmp, bref->data_off, chain->bytes, &dio);
1041 KKASSERT(error == 0);
1042 callback(dio, chain, arg_p, arg_o);
1047 * Otherwise issue a read
1049 adjreadcounter(&chain->bref, chain->bytes);
1050 hammer2_io_breadcb(hmp, bref->data_off, chain->bytes,
1051 callback, chain, arg_p, arg_o);
1055 * Unlock and deref a chain element.
1057 * On the last lock release any non-embedded data (chain->dio) will be
1061 hammer2_chain_unlock(hammer2_chain_t *chain)
1063 hammer2_chain_core_t *core = chain->core;
1064 ccms_state_t ostate;
1069 * The core->cst lock can be shared across several chains so we
1070 * need to track the per-chain lockcnt separately.
1072 * If multiple locks are present (or being attempted) on this
1073 * particular chain we can just unlock, drop refs, and return.
1075 * Otherwise fall-through on the 1->0 transition.
1078 lockcnt = chain->lockcnt;
1079 KKASSERT(lockcnt > 0);
1082 if (atomic_cmpset_int(&chain->lockcnt,
1083 lockcnt, lockcnt - 1)) {
1084 ccms_thread_unlock(&core->cst);
1085 hammer2_chain_drop(chain);
1089 if (atomic_cmpset_int(&chain->lockcnt, 1, 0))
1096 * On the 1->0 transition we upgrade the core lock (if necessary)
1097 * to exclusive for terminal processing. If after upgrading we find
1098 * that lockcnt is non-zero, another thread is racing us and will
1099 * handle the unload for us later on, so just cleanup and return
1100 * leaving the data/io intact
1102 * Otherwise if lockcnt is still 0 it is possible for it to become
1103 * non-zero and race, but since we hold the core->cst lock
1104 * exclusively all that will happen is that the chain will be
1105 * reloaded after we unload it.
1107 ostate = ccms_thread_lock_upgrade(&core->cst);
1108 if (chain->lockcnt) {
1109 ccms_thread_unlock_upgraded(&core->cst, ostate);
1110 hammer2_chain_drop(chain);
1115 * Shortcut the case if the data is embedded or not resolved.
1117 * Do NOT NULL out chain->data (e.g. inode data), it might be
1120 if (chain->dio == NULL) {
1121 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0)
1122 hammer2_chain_drop_data(chain, 0);
1123 ccms_thread_unlock_upgraded(&core->cst, ostate);
1124 hammer2_chain_drop(chain);
1131 if (hammer2_io_isdirty(chain->dio) == 0) {
1133 } else if (chain->flags & HAMMER2_CHAIN_IOFLUSH) {
1134 switch(chain->bref.type) {
1135 case HAMMER2_BREF_TYPE_DATA:
1136 counterp = &hammer2_ioa_file_write;
1138 case HAMMER2_BREF_TYPE_INODE:
1139 counterp = &hammer2_ioa_meta_write;
1141 case HAMMER2_BREF_TYPE_INDIRECT:
1142 counterp = &hammer2_ioa_indr_write;
1144 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1145 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1146 counterp = &hammer2_ioa_fmap_write;
1149 counterp = &hammer2_ioa_volu_write;
1152 *counterp += chain->bytes;
1154 switch(chain->bref.type) {
1155 case HAMMER2_BREF_TYPE_DATA:
1156 counterp = &hammer2_iod_file_write;
1158 case HAMMER2_BREF_TYPE_INODE:
1159 counterp = &hammer2_iod_meta_write;
1161 case HAMMER2_BREF_TYPE_INDIRECT:
1162 counterp = &hammer2_iod_indr_write;
1164 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1165 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1166 counterp = &hammer2_iod_fmap_write;
1169 counterp = &hammer2_iod_volu_write;
1172 *counterp += chain->bytes;
1176 * Clean out the dio.
1178 * If a device buffer was used for data be sure to destroy the
1179 * buffer when we are done to avoid aliases (XXX what about the
1180 * underlying VM pages?).
1182 * NOTE: Freemap leaf's use reserved blocks and thus no aliasing
1185 * NOTE: The isdirty check tracks whether we have to bdwrite() the
1186 * buffer or not. The buffer might already be dirty. The
1187 * flag is re-set when chain_modify() is called, even if
1188 * MODIFIED is already set, allowing the OS to retire the
1189 * buffer independent of a hammer2 flush.
1192 if ((chain->flags & HAMMER2_CHAIN_IOFLUSH) &&
1193 hammer2_io_isdirty(chain->dio)) {
1194 hammer2_io_bawrite(&chain->dio);
1196 hammer2_io_bqrelse(&chain->dio);
1198 ccms_thread_unlock_upgraded(&core->cst, ostate);
1199 hammer2_chain_drop(chain);
1203 * This counts the number of live blockrefs in a block array and
1204 * also calculates the point at which all remaining blockrefs are empty.
1206 * NOTE: Flag is not set until after the count is complete, allowing
1207 * callers to test the flag without holding the spinlock.
1209 * NOTE: If base is NULL the related chain is still in the INITIAL
1210 * state and there are no blockrefs to count.
1212 * NOTE: live_count may already have some counts accumulated due to
1213 * creation and deletion and could even be initially negative.
1216 hammer2_chain_countbrefs(hammer2_chain_t *chain,
1217 hammer2_blockref_t *base, int count)
1219 hammer2_chain_core_t *core = chain->core;
1221 spin_lock(&core->cst.spin);
1222 if ((core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0) {
1224 while (--count >= 0) {
1225 if (base[count].type)
1228 core->live_zero = count + 1;
1229 while (count >= 0) {
1230 if (base[count].type)
1231 atomic_add_int(&core->live_count, 1);
1235 core->live_zero = 0;
1237 /* else do not modify live_count */
1238 atomic_set_int(&core->flags, HAMMER2_CORE_COUNTEDBREFS);
1240 spin_unlock(&core->cst.spin);
1244 * Resize the chain's physical storage allocation in-place. This may
1245 * replace the passed-in chain with a new chain.
1247 * Chains can be resized smaller without reallocating the storage.
1248 * Resizing larger will reallocate the storage.
1250 * Must be passed an exclusively locked parent and chain, returns a new
1251 * exclusively locked chain at the same index and unlocks the old chain.
1252 * Flushes the buffer if necessary.
1254 * This function is mostly used with DATA blocks locked RESOLVE_NEVER in order
1255 * to avoid instantiating a device buffer that conflicts with the vnode
1256 * data buffer. That is, the passed-in bp is a logical buffer, whereas
1257 * any chain-oriented bp would be a device buffer.
1259 * XXX return error if cannot resize.
1262 hammer2_chain_resize(hammer2_trans_t *trans, hammer2_inode_t *ip,
1263 hammer2_chain_t *parent, hammer2_chain_t **chainp,
1264 int nradix, int flags)
1266 hammer2_mount_t *hmp;
1267 hammer2_chain_t *chain;
1275 * Only data and indirect blocks can be resized for now.
1276 * (The volu root, inodes, and freemap elements use a fixed size).
1278 KKASSERT(chain != &hmp->vchain);
1279 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA ||
1280 chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT);
1283 * Nothing to do if the element is already the proper size
1285 obytes = chain->bytes;
1286 nbytes = 1U << nradix;
1287 if (obytes == nbytes)
1291 * Delete the old chain and duplicate it at the same (parent, index),
1292 * returning a new chain. This allows the old chain to still be
1293 * used by the flush code. The new chain will be returned in a
1296 * The parent does not have to be locked for the delete/duplicate call,
1297 * but is in this particular code path.
1299 * NOTE: If we are not crossing a synchronization point the
1300 * duplication code will simply reuse the existing chain
1303 hammer2_chain_delete_duplicate(trans, &chain, 0);
1306 * Relocate the block, even if making it smaller (because different
1307 * block sizes may be in different regions).
1309 hammer2_freemap_alloc(trans, chain->hmp, &chain->bref, nbytes);
1310 chain->bytes = nbytes;
1311 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
1312 /*ip->delta_dcount += (ssize_t)(nbytes - obytes);*/ /* XXX atomic */
1315 * For now just support it on DATA chains (and not on indirect
1318 KKASSERT(chain->dio == NULL);
1322 * Make sure the chain is marked MOVED and propagate the update
1323 * to the root for flush.
1325 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
1326 hammer2_chain_ref(chain);
1327 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
1329 hammer2_chain_setsubmod(trans, chain);
1335 * Set a chain modified, making it read-write and duplicating it if necessary.
1336 * This function will assign a new physical block to the chain if necessary
1338 * Duplication of already-modified chains is possible when the modification
1339 * crosses a flush synchronization boundary.
1341 * Non-data blocks - The chain should be locked to at least the RESOLVE_MAYBE
1342 * level or the COW operation will not work.
1344 * Data blocks - The chain is usually locked RESOLVE_NEVER so as not to
1345 * run the data through the device buffers.
1347 * This function may return a different chain than was passed, in which case
1348 * the old chain will be unlocked and the new chain will be locked.
1350 * ip->chain may be adjusted by hammer2_chain_modify_ip().
1352 hammer2_inode_data_t *
1353 hammer2_chain_modify_ip(hammer2_trans_t *trans, hammer2_inode_t *ip,
1354 hammer2_chain_t **chainp, int flags)
1356 atomic_set_int(&ip->flags, HAMMER2_INODE_MODIFIED);
1357 hammer2_chain_modify(trans, chainp, flags);
1358 if (ip->chain != *chainp)
1359 hammer2_inode_repoint(ip, NULL, *chainp);
1361 vsetisdirty(ip->vp);
1362 return(&ip->chain->data->ipdata);
1366 hammer2_chain_modify(hammer2_trans_t *trans, hammer2_chain_t **chainp,
1369 hammer2_mount_t *hmp;
1370 hammer2_chain_t *chain;
1380 kprintf("MODIFY %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1383 * Data must be resolved if already assigned unless explicitly
1384 * flagged otherwise.
1386 if (chain->data == NULL && (flags & HAMMER2_MODIFY_OPTDATA) == 0 &&
1387 (chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX)) {
1388 hammer2_chain_lock(chain, HAMMER2_RESOLVE_ALWAYS);
1389 hammer2_chain_unlock(chain);
1393 * data is not optional for freemap chains (we must always be sure
1394 * to copy the data on COW storage allocations).
1396 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
1397 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
1398 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) ||
1399 (flags & HAMMER2_MODIFY_OPTDATA) == 0);
1403 * Determine if a delete-duplicate is needed.
1405 * (a) Modify_tid is part of a prior flush
1406 * (b) Transaction is concurrent with a flush (has higher tid)
1407 * (c) and chain is not in the initial state (freshly created)
1408 * (d) and caller didn't request an in-place modification.
1410 * The freemap and volume header special chains are never D-Dd.
1412 if (chain->modify_tid != trans->sync_tid && /* cross boundary */
1413 (flags & HAMMER2_MODIFY_INPLACE) == 0) { /* from d-d */
1414 if (chain != &hmp->fchain && chain != &hmp->vchain) {
1415 KKASSERT((flags & HAMMER2_MODIFY_ASSERTNOCOPY) == 0);
1416 hammer2_chain_delete_duplicate(trans, chainp, 0);
1418 kprintf("RET1A %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1422 kprintf("RET1B %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1426 /* fall through if fchain or vchain */
1430 * Otherwise do initial-chain handling
1432 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) {
1433 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
1434 hammer2_chain_ref(chain);
1438 * The modification or re-modification requires an allocation and
1441 * We normally always allocate new storage here. If storage exists
1442 * and MODIFY_NOREALLOC is passed in, we do not allocate new storage.
1444 if (chain != &hmp->vchain && chain != &hmp->fchain) {
1445 if ((chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX) == 0 ||
1446 ((flags & HAMMER2_MODIFY_NOREALLOC) == 0 &&
1447 chain->modify_tid != trans->sync_tid)
1449 hammer2_freemap_alloc(trans, chain->hmp,
1450 &chain->bref, chain->bytes);
1451 /* XXX failed allocation */
1452 } else if (chain->flags & HAMMER2_CHAIN_FORCECOW) {
1453 hammer2_freemap_alloc(trans, chain->hmp,
1454 &chain->bref, chain->bytes);
1455 /* XXX failed allocation */
1457 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
1460 chain->modify_tid = trans->sync_tid;
1461 if ((flags & HAMMER2_MODIFY_NO_MODIFY_TID) == 0)
1462 chain->bref.modify_tid = trans->sync_tid;
1465 * Do not COW if OPTDATA is set. INITIAL flag remains unchanged.
1466 * (OPTDATA does not prevent [re]allocation of storage, only the
1467 * related copy-on-write op).
1469 if (flags & HAMMER2_MODIFY_OPTDATA)
1473 * Clearing the INITIAL flag (for indirect blocks) indicates that
1474 * we've processed the uninitialized storage allocation.
1476 * If this flag is already clear we are likely in a copy-on-write
1477 * situation but we have to be sure NOT to bzero the storage if
1478 * no data is present.
1480 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
1481 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1488 * Instantiate data buffer and possibly execute COW operation
1490 switch(chain->bref.type) {
1491 case HAMMER2_BREF_TYPE_VOLUME:
1492 case HAMMER2_BREF_TYPE_FREEMAP:
1493 case HAMMER2_BREF_TYPE_INODE:
1494 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1496 * The data is embedded, no copy-on-write operation is
1499 KKASSERT(chain->dio == NULL);
1501 case HAMMER2_BREF_TYPE_DATA:
1502 case HAMMER2_BREF_TYPE_INDIRECT:
1503 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1505 * Perform the copy-on-write operation
1507 KKASSERT(chain != &hmp->vchain && chain != &hmp->fchain);
1510 error = hammer2_io_new(hmp, chain->bref.data_off,
1511 chain->bytes, &dio);
1513 error = hammer2_io_bread(hmp, chain->bref.data_off,
1514 chain->bytes, &dio);
1516 adjreadcounter(&chain->bref, chain->bytes);
1517 KKASSERT(error == 0);
1519 bdata = hammer2_io_data(dio, chain->bref.data_off);
1522 * Copy or zero-fill on write depending on whether
1523 * chain->data exists or not and set the dirty state for
1524 * the new buffer. Retire the existing buffer.
1527 KKASSERT(chain->dio != NULL);
1528 if (chain->data != (void *)bdata) {
1529 bcopy(chain->data, bdata, chain->bytes);
1531 } else if (wasinitial == 0) {
1533 * We have a problem. We were asked to COW but
1534 * we don't have any data to COW with!
1536 panic("hammer2_chain_modify: having a COW %p\n",
1539 hammer2_io_brelse(&chain->dio);
1540 chain->data = (void *)bdata;
1542 hammer2_io_setdirty(dio); /* modified by bcopy above */
1545 panic("hammer2_chain_modify: illegal non-embedded type %d",
1552 kprintf("RET2 %p.%d flags %08x mod=%016jx del=%016jx\n", chain, chain->bref.type, chain->flags, chain->modify_tid, chain->delete_tid);
1554 hammer2_chain_setsubmod(trans, chain);
1558 * Mark the volume as having been modified. This short-cut version
1559 * does not have to lock the volume's chain, which allows the ioctl
1560 * code to make adjustments to connections without deadlocking. XXX
1562 * No ref is made on vchain when flagging it MODIFIED.
1565 hammer2_modify_volume(hammer2_mount_t *hmp)
1567 hammer2_voldata_lock(hmp);
1568 hammer2_voldata_unlock(hmp, 1);
1572 * This function returns the chain at the nearest key within the specified
1573 * range with the highest delete_tid. The core spinlock must be held on
1574 * call and the returned chain will be referenced but not locked.
1576 * The returned chain may or may not be in a deleted state. Note that
1577 * live chains have a delete_tid = MAX_TID.
1579 * This function will recurse through chain->rbtree as necessary and will
1580 * return a *key_nextp suitable for iteration. *key_nextp is only set if
1581 * the iteration value is less than the current value of *key_nextp.
1583 * The caller should use (*key_nextp) to calculate the actual range of
1584 * the returned element, which will be (key_beg to *key_nextp - 1), because
1585 * there might be another element which is superior to the returned element
1588 * (*key_nextp) can be passed as key_beg in an iteration only while non-NULL
1589 * chains continue to be returned. On EOF (*key_nextp) may overflow since
1590 * it will wind up being (key_end + 1).
1592 struct hammer2_chain_find_info {
1593 hammer2_chain_t *best;
1594 hammer2_key_t key_beg;
1595 hammer2_key_t key_end;
1596 hammer2_key_t key_next;
1599 static int hammer2_chain_find_cmp(hammer2_chain_t *child, void *data);
1600 static int hammer2_chain_find_callback(hammer2_chain_t *child, void *data);
1604 hammer2_chain_find(hammer2_chain_t *parent, hammer2_key_t *key_nextp,
1605 hammer2_key_t key_beg, hammer2_key_t key_end)
1607 struct hammer2_chain_find_info info;
1608 hammer2_chain_layer_t *layer;
1611 info.key_beg = key_beg;
1612 info.key_end = key_end;
1613 info.key_next = *key_nextp;
1615 KKASSERT(parent->core->good == 0x1234);
1616 TAILQ_FOREACH(layer, &parent->core->layerq, entry) {
1617 KKASSERT(layer->good == 0xABCD);
1618 RB_SCAN(hammer2_chain_tree, &layer->rbtree,
1619 hammer2_chain_find_cmp, hammer2_chain_find_callback,
1622 *key_nextp = info.key_next;
1624 kprintf("chain_find %p %016jx:%016jx next=%016jx\n",
1625 parent, key_beg, key_end, *key_nextp);
1633 hammer2_chain_find_cmp(hammer2_chain_t *child, void *data)
1635 struct hammer2_chain_find_info *info = data;
1636 hammer2_key_t child_beg;
1637 hammer2_key_t child_end;
1639 child_beg = child->bref.key;
1640 child_end = child_beg + ((hammer2_key_t)1 << child->bref.keybits) - 1;
1642 if (child_end < info->key_beg)
1644 if (child_beg > info->key_end)
1651 hammer2_chain_find_callback(hammer2_chain_t *child, void *data)
1653 struct hammer2_chain_find_info *info = data;
1654 hammer2_chain_t *best;
1655 hammer2_key_t child_end;
1659 * Skip deleted chains which have been flushed (MOVED no longer set),
1660 * causes caller to check blockref array.
1662 if ((child->flags & (HAMMER2_CHAIN_DELETED | HAMMER2_CHAIN_MOVED)) ==
1663 HAMMER2_CHAIN_DELETED) {
1672 if ((best = info->best) == NULL) {
1674 * No previous best. Assign best
1677 } else if (best->bref.key <= info->key_beg &&
1678 child->bref.key <= info->key_beg) {
1680 * If our current best is flush with key_beg and child is
1681 * also flush with key_beg choose based on delete_tid.
1683 * key_next will automatically be limited to the smaller of
1684 * the two end-points.
1686 if (child->delete_tid > best->delete_tid)
1688 } else if (child->bref.key < best->bref.key) {
1690 * Child has a nearer key and best is not flush with key_beg.
1691 * Truncate key_next to the old best key iff it had a better
1695 if (best->delete_tid >= child->delete_tid &&
1696 (info->key_next > best->bref.key || info->key_next == 0))
1697 info->key_next = best->bref.key;
1698 } else if (child->bref.key == best->bref.key) {
1700 * If our current best is flush with the child then choose
1701 * based on delete_tid.
1703 * key_next will automatically be limited to the smaller of
1704 * the two end-points.
1706 if (child->delete_tid > best->delete_tid)
1710 * Keep the current best but truncate key_next to the child's
1711 * base iff the child has a higher delete_tid.
1713 * key_next will also automatically be limited to the smaller
1714 * of the two end-points (probably not necessary for this case
1715 * but we do it anyway).
1717 if (child->delete_tid >= best->delete_tid &&
1718 (info->key_next > child->bref.key || info->key_next == 0))
1719 info->key_next = child->bref.key;
1723 * Always truncate key_next based on child's end-of-range.
1725 child_end = child->bref.key + ((hammer2_key_t)1 << child->bref.keybits);
1726 if (child_end && (info->key_next > child_end || info->key_next == 0))
1727 info->key_next = child_end;
1733 * Retrieve the specified chain from a media blockref, creating the
1734 * in-memory chain structure which reflects it. modify_tid will be
1735 * left 0 which forces any modifications to issue a delete-duplicate.
1737 * NULL is returned if the insertion races.
1739 * Caller must hold the parent locked shared or exclusive since we may
1740 * need the parent's bref array to find our block.
1743 hammer2_chain_get(hammer2_chain_t *parent, hammer2_blockref_t *bref)
1745 hammer2_mount_t *hmp = parent->hmp;
1746 hammer2_chain_core_t *above = parent->core;
1747 hammer2_chain_t *chain;
1750 * Allocate a chain structure representing the existing media
1751 * entry. Resulting chain has one ref and is not locked.
1753 chain = hammer2_chain_alloc(hmp, parent->pmp, NULL, bref);
1754 hammer2_chain_core_alloc(NULL, chain, NULL);
1755 /* ref'd chain returned */
1756 chain->modify_tid = chain->bref.mirror_tid;
1759 * Link the chain into its parent. A spinlock is required to safely
1760 * access the RBTREE, and it is possible to collide with another
1761 * hammer2_chain_get() operation because the caller might only hold
1762 * a shared lock on the parent.
1764 KKASSERT(parent->refs > 0);
1765 hammer2_chain_insert(above, NULL, chain,
1766 HAMMER2_CHAIN_INSERT_SPIN |
1767 HAMMER2_CHAIN_INSERT_RACE);
1768 if ((chain->flags & HAMMER2_CHAIN_ONRBTREE) == 0) {
1769 kprintf("chain %p not on RBTREE\n", chain);
1770 hammer2_chain_drop(chain);
1775 * Return our new chain referenced but not locked.
1781 * Lookup initialization/completion API
1784 hammer2_chain_lookup_init(hammer2_chain_t *parent, int flags)
1786 if (flags & HAMMER2_LOOKUP_SHARED) {
1787 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS |
1788 HAMMER2_RESOLVE_SHARED);
1790 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
1796 hammer2_chain_lookup_done(hammer2_chain_t *parent)
1799 hammer2_chain_unlock(parent);
1804 hammer2_chain_getparent(hammer2_chain_t **parentp, int how)
1806 hammer2_chain_t *oparent;
1807 hammer2_chain_t *bparent;
1808 hammer2_chain_t *nparent;
1809 hammer2_chain_core_t *above;
1812 above = oparent->above;
1814 spin_lock(&above->cst.spin);
1815 bparent = TAILQ_FIRST(&above->ownerq);
1816 hammer2_chain_ref(bparent);
1819 * Be careful of order, oparent must be unlocked before nparent
1820 * is locked below to avoid a deadlock. We might as well delay its
1821 * unlocking until we conveniently no longer have the spinlock (instead
1822 * of cycling the spinlock).
1824 * Theoretically our ref on bparent should prevent elements of the
1825 * following chain from going away and prevent above from going away,
1826 * but we still need the spinlock to safely scan the list.
1830 while (nparent->flags & HAMMER2_CHAIN_DUPLICATED)
1831 nparent = TAILQ_NEXT(nparent, core_entry);
1832 hammer2_chain_ref(nparent);
1833 spin_unlock(&above->cst.spin);
1836 hammer2_chain_unlock(oparent);
1839 hammer2_chain_lock(nparent, how | HAMMER2_RESOLVE_NOREF);
1840 hammer2_chain_drop(bparent);
1843 * We might have raced a delete-duplicate.
1845 if ((nparent->flags & HAMMER2_CHAIN_DUPLICATED) == 0)
1848 hammer2_chain_ref(bparent);
1849 hammer2_chain_unlock(nparent);
1850 spin_lock(&above->cst.spin);
1859 * Locate the first chain whos key range overlaps (key_beg, key_end) inclusive.
1860 * (*parentp) typically points to an inode but can also point to a related
1861 * indirect block and this function will recurse upwards and find the inode
1864 * (*parentp) must be exclusively locked and referenced and can be an inode
1865 * or an existing indirect block within the inode.
1867 * On return (*parentp) will be modified to point at the deepest parent chain
1868 * element encountered during the search, as a helper for an insertion or
1869 * deletion. The new (*parentp) will be locked and referenced and the old
1870 * will be unlocked and dereferenced (no change if they are both the same).
1872 * The matching chain will be returned exclusively locked. If NOLOCK is
1873 * requested the chain will be returned only referenced.
1875 * NULL is returned if no match was found, but (*parentp) will still
1876 * potentially be adjusted.
1878 * On return (*key_nextp) will point to an iterative value for key_beg.
1879 * (If NULL is returned (*key_nextp) is set to key_end).
1881 * This function will also recurse up the chain if the key is not within the
1882 * current parent's range. (*parentp) can never be set to NULL. An iteration
1883 * can simply allow (*parentp) to float inside the loop.
1885 * NOTE! chain->data is not always resolved. By default it will not be
1886 * resolved for BREF_TYPE_DATA, FREEMAP_NODE, or FREEMAP_LEAF. Use
1887 * HAMMER2_LOOKUP_ALWAYS to force resolution (but be careful w/
1888 * BREF_TYPE_DATA as the device buffer can alias the logical file
1892 hammer2_chain_lookup(hammer2_chain_t **parentp, hammer2_key_t *key_nextp,
1893 hammer2_key_t key_beg, hammer2_key_t key_end,
1894 int *cache_indexp, int flags)
1896 hammer2_mount_t *hmp;
1897 hammer2_chain_t *parent;
1898 hammer2_chain_t *chain;
1899 hammer2_blockref_t *base;
1900 hammer2_blockref_t *bref;
1901 hammer2_blockref_t bcopy;
1902 hammer2_key_t scan_beg;
1903 hammer2_key_t scan_end;
1904 hammer2_chain_core_t *above;
1906 int how_always = HAMMER2_RESOLVE_ALWAYS;
1907 int how_maybe = HAMMER2_RESOLVE_MAYBE;
1910 if (flags & HAMMER2_LOOKUP_ALWAYS) {
1911 how_maybe = how_always;
1912 how = HAMMER2_RESOLVE_ALWAYS;
1913 } else if (flags & (HAMMER2_LOOKUP_NODATA | HAMMER2_LOOKUP_NOLOCK)) {
1914 how = HAMMER2_RESOLVE_NEVER;
1916 how = HAMMER2_RESOLVE_MAYBE;
1918 if (flags & (HAMMER2_LOOKUP_SHARED | HAMMER2_LOOKUP_NOLOCK)) {
1919 how_maybe |= HAMMER2_RESOLVE_SHARED;
1920 how_always |= HAMMER2_RESOLVE_SHARED;
1921 how |= HAMMER2_RESOLVE_SHARED;
1925 * Recurse (*parentp) upward if necessary until the parent completely
1926 * encloses the key range or we hit the inode.
1928 * This function handles races against the flusher doing a delete-
1929 * duplicate above us and re-homes the parent to the duplicate in
1930 * that case, otherwise we'd wind up recursing down a stale chain.
1935 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
1936 parent->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
1937 scan_beg = parent->bref.key;
1938 scan_end = scan_beg +
1939 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
1940 if (key_beg >= scan_beg && key_end <= scan_end)
1942 parent = hammer2_chain_getparent(parentp, how_maybe);
1947 * Locate the blockref array. Currently we do a fully associative
1948 * search through the array.
1950 switch(parent->bref.type) {
1951 case HAMMER2_BREF_TYPE_INODE:
1953 * Special shortcut for embedded data returns the inode
1954 * itself. Callers must detect this condition and access
1955 * the embedded data (the strategy code does this for us).
1957 * This is only applicable to regular files and softlinks.
1959 if (parent->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA) {
1960 if (flags & HAMMER2_LOOKUP_NOLOCK)
1961 hammer2_chain_ref(parent);
1963 hammer2_chain_lock(parent, how_always);
1964 *key_nextp = key_end + 1;
1967 base = &parent->data->ipdata.u.blockset.blockref[0];
1968 count = HAMMER2_SET_COUNT;
1970 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1971 case HAMMER2_BREF_TYPE_INDIRECT:
1973 * Handle MATCHIND on the parent
1975 if (flags & HAMMER2_LOOKUP_MATCHIND) {
1976 scan_beg = parent->bref.key;
1977 scan_end = scan_beg +
1978 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
1979 if (key_beg == scan_beg && key_end == scan_end) {
1981 hammer2_chain_lock(chain, how_maybe);
1982 *key_nextp = scan_end + 1;
1987 * Optimize indirect blocks in the INITIAL state to avoid
1990 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
1993 if (parent->data == NULL)
1994 panic("parent->data is NULL");
1995 base = &parent->data->npdata[0];
1997 count = parent->bytes / sizeof(hammer2_blockref_t);
1999 case HAMMER2_BREF_TYPE_VOLUME:
2000 base = &hmp->voldata.sroot_blockset.blockref[0];
2001 count = HAMMER2_SET_COUNT;
2003 case HAMMER2_BREF_TYPE_FREEMAP:
2004 base = &hmp->voldata.freemap_blockset.blockref[0];
2005 count = HAMMER2_SET_COUNT;
2008 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
2010 base = NULL; /* safety */
2011 count = 0; /* safety */
2015 * Merged scan to find next candidate.
2017 * hammer2_base_*() functions require the above->live_* fields
2018 * to be synchronized.
2020 * We need to hold the spinlock to access the block array and RB tree
2021 * and to interlock chain creation.
2023 above = parent->core;
2024 if ((parent->core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0)
2025 hammer2_chain_countbrefs(parent, base, count);
2030 spin_lock(&above->cst.spin);
2031 chain = hammer2_combined_find(parent, base, count,
2032 cache_indexp, key_nextp,
2033 key_beg, key_end, &bref);
2036 * Exhausted parent chain, iterate.
2039 spin_unlock(&above->cst.spin);
2040 if (key_beg == key_end) /* short cut single-key case */
2042 return (hammer2_chain_next(parentp, NULL, key_nextp,
2044 cache_indexp, flags));
2048 * Selected from blockref or in-memory chain.
2050 if (chain == NULL) {
2052 spin_unlock(&above->cst.spin);
2053 chain = hammer2_chain_get(parent, &bcopy);
2054 if (chain == NULL) {
2055 kprintf("retry lookup parent %p keys %016jx:%016jx\n",
2056 parent, key_beg, key_end);
2059 if (bcmp(&bcopy, bref, sizeof(bcopy))) {
2060 hammer2_chain_drop(chain);
2064 hammer2_chain_ref(chain);
2065 spin_unlock(&above->cst.spin);
2067 /* chain is referenced but not locked */
2070 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX)
2072 * NOTE: chain's key range is not relevant as there might be
2073 * one-offs within the range that are not deleted.
2075 if (chain->flags & HAMMER2_CHAIN_DELETED) {
2076 hammer2_chain_drop(chain);
2077 key_beg = *key_nextp;
2078 if (key_beg == 0 || key_beg > key_end)
2084 * If the chain element is an indirect block it becomes the new
2085 * parent and we loop on it. We must maintain our top-down locks
2086 * to prevent the flusher from interfering (i.e. doing a
2087 * delete-duplicate and leaving us recursing down a deleted chain).
2089 * The parent always has to be locked with at least RESOLVE_MAYBE
2090 * so we can access its data. It might need a fixup if the caller
2091 * passed incompatible flags. Be careful not to cause a deadlock
2092 * as a data-load requires an exclusive lock.
2094 * If HAMMER2_LOOKUP_MATCHIND is set and the indirect block's key
2095 * range is within the requested key range we return the indirect
2096 * block and do NOT loop. This is usually only used to acquire
2099 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
2100 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2101 hammer2_chain_lock(chain, how_maybe | HAMMER2_RESOLVE_NOREF);
2102 hammer2_chain_unlock(parent);
2103 *parentp = parent = chain;
2107 hammer2_chain_lock(chain, how | HAMMER2_RESOLVE_NOREF);
2110 * All done, return the chain
2116 * After having issued a lookup we can iterate all matching keys.
2118 * If chain is non-NULL we continue the iteration from just after it's index.
2120 * If chain is NULL we assume the parent was exhausted and continue the
2121 * iteration at the next parent.
2123 * parent must be locked on entry and remains locked throughout. chain's
2124 * lock status must match flags. Chain is always at least referenced.
2126 * WARNING! The MATCHIND flag does not apply to this function.
2129 hammer2_chain_next(hammer2_chain_t **parentp, hammer2_chain_t *chain,
2130 hammer2_key_t *key_nextp,
2131 hammer2_key_t key_beg, hammer2_key_t key_end,
2132 int *cache_indexp, int flags)
2134 hammer2_chain_t *parent;
2138 * Calculate locking flags for upward recursion.
2140 how_maybe = HAMMER2_RESOLVE_MAYBE;
2141 if (flags & (HAMMER2_LOOKUP_SHARED | HAMMER2_LOOKUP_NOLOCK))
2142 how_maybe |= HAMMER2_RESOLVE_SHARED;
2147 * Calculate the next index and recalculate the parent if necessary.
2150 key_beg = chain->bref.key +
2151 ((hammer2_key_t)1 << chain->bref.keybits);
2152 if (flags & HAMMER2_LOOKUP_NOLOCK)
2153 hammer2_chain_drop(chain);
2155 hammer2_chain_unlock(chain);
2158 * Any scan where the lookup returned degenerate data embedded
2159 * in the inode has an invalid index and must terminate.
2161 if (chain == parent)
2163 if (key_beg == 0 || key_beg > key_end)
2166 } else if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT &&
2167 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2169 * We reached the end of the iteration.
2174 * Continue iteration with next parent unless the current
2175 * parent covers the range.
2177 key_beg = parent->bref.key +
2178 ((hammer2_key_t)1 << parent->bref.keybits);
2179 if (key_beg == 0 || key_beg > key_end)
2181 parent = hammer2_chain_getparent(parentp, how_maybe);
2187 return (hammer2_chain_lookup(parentp, key_nextp,
2189 cache_indexp, flags));
2193 * Create and return a new hammer2 system memory structure of the specified
2194 * key, type and size and insert it under (*parentp). This is a full
2195 * insertion, based on the supplied key/keybits, and may involve creating
2196 * indirect blocks and moving other chains around via delete/duplicate.
2198 * (*parentp) must be exclusive locked and may be replaced on return
2199 * depending on how much work the function had to do.
2201 * (*chainp) usually starts out NULL and returns the newly created chain,
2202 * but if the caller desires the caller may allocate a disconnected chain
2203 * and pass it in instead. (It is also possible for the caller to use
2204 * chain_duplicate() to create a disconnected chain, manipulate it, then
2205 * pass it into this function to insert it).
2207 * This function should NOT be used to insert INDIRECT blocks. It is
2208 * typically used to create/insert inodes and data blocks.
2210 * Caller must pass-in an exclusively locked parent the new chain is to
2211 * be inserted under, and optionally pass-in a disconnected, exclusively
2212 * locked chain to insert (else we create a new chain). The function will
2213 * adjust (*parentp) as necessary, create or connect the chain, and
2214 * return an exclusively locked chain in *chainp.
2217 hammer2_chain_create(hammer2_trans_t *trans, hammer2_chain_t **parentp,
2218 hammer2_chain_t **chainp,
2219 hammer2_key_t key, int keybits, int type, size_t bytes)
2221 hammer2_mount_t *hmp;
2222 hammer2_chain_t *chain;
2223 hammer2_chain_t *parent = *parentp;
2224 hammer2_chain_core_t *above;
2225 hammer2_blockref_t *base;
2226 hammer2_blockref_t dummy;
2231 above = parent->core;
2232 KKASSERT(ccms_thread_lock_owned(&above->cst));
2236 if (chain == NULL) {
2238 * First allocate media space and construct the dummy bref,
2239 * then allocate the in-memory chain structure. Set the
2240 * INITIAL flag for fresh chains which do not have embedded
2243 bzero(&dummy, sizeof(dummy));
2246 dummy.keybits = keybits;
2247 dummy.data_off = hammer2_getradix(bytes);
2248 dummy.methods = parent->bref.methods;
2249 chain = hammer2_chain_alloc(hmp, parent->pmp, trans, &dummy);
2250 hammer2_chain_core_alloc(trans, chain, NULL);
2253 * Lock the chain manually, chain_lock will load the chain
2254 * which we do NOT want to do. (note: chain->refs is set
2255 * to 1 by chain_alloc() for us, but lockcnt is not).
2258 ccms_thread_lock(&chain->core->cst, CCMS_STATE_EXCLUSIVE);
2262 * We do NOT set INITIAL here (yet). INITIAL is only
2263 * used for indirect blocks.
2265 * Recalculate bytes to reflect the actual media block
2268 bytes = (hammer2_off_t)1 <<
2269 (int)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
2270 chain->bytes = bytes;
2273 case HAMMER2_BREF_TYPE_VOLUME:
2274 case HAMMER2_BREF_TYPE_FREEMAP:
2275 panic("hammer2_chain_create: called with volume type");
2277 case HAMMER2_BREF_TYPE_INODE:
2278 KKASSERT(bytes == HAMMER2_INODE_BYTES);
2279 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
2280 chain->data = kmalloc(sizeof(chain->data->ipdata),
2281 hmp->mchain, M_WAITOK | M_ZERO);
2283 case HAMMER2_BREF_TYPE_INDIRECT:
2284 panic("hammer2_chain_create: cannot be used to"
2285 "create indirect block");
2287 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2288 panic("hammer2_chain_create: cannot be used to"
2289 "create freemap root or node");
2291 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2292 KKASSERT(bytes == sizeof(chain->data->bmdata));
2293 atomic_set_int(&chain->flags, HAMMER2_CHAIN_EMBEDDED);
2294 chain->data = kmalloc(sizeof(chain->data->bmdata),
2295 hmp->mchain, M_WAITOK | M_ZERO);
2297 case HAMMER2_BREF_TYPE_DATA:
2300 * leave chain->data NULL, set INITIAL
2302 KKASSERT(chain->data == NULL);
2303 atomic_set_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
2308 * Potentially update the existing chain's key/keybits.
2310 * Do NOT mess with the current state of the INITIAL flag.
2312 chain->bref.key = key;
2313 chain->bref.keybits = keybits;
2314 KKASSERT(chain->above == NULL);
2318 * Calculate how many entries we have in the blockref array and
2319 * determine if an indirect block is required.
2322 above = parent->core;
2324 switch(parent->bref.type) {
2325 case HAMMER2_BREF_TYPE_INODE:
2326 KKASSERT((parent->data->ipdata.op_flags &
2327 HAMMER2_OPFLAG_DIRECTDATA) == 0);
2328 KKASSERT(parent->data != NULL);
2329 base = &parent->data->ipdata.u.blockset.blockref[0];
2330 count = HAMMER2_SET_COUNT;
2332 case HAMMER2_BREF_TYPE_INDIRECT:
2333 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2334 if (parent->flags & HAMMER2_CHAIN_INITIAL)
2337 base = &parent->data->npdata[0];
2338 count = parent->bytes / sizeof(hammer2_blockref_t);
2340 case HAMMER2_BREF_TYPE_VOLUME:
2341 KKASSERT(parent->data != NULL);
2342 base = &hmp->voldata.sroot_blockset.blockref[0];
2343 count = HAMMER2_SET_COUNT;
2345 case HAMMER2_BREF_TYPE_FREEMAP:
2346 KKASSERT(parent->data != NULL);
2347 base = &hmp->voldata.freemap_blockset.blockref[0];
2348 count = HAMMER2_SET_COUNT;
2351 panic("hammer2_chain_create: unrecognized blockref type: %d",
2359 * Make sure we've counted the brefs
2361 if ((parent->core->flags & HAMMER2_CORE_COUNTEDBREFS) == 0)
2362 hammer2_chain_countbrefs(parent, base, count);
2364 KKASSERT(above->live_count >= 0 && above->live_count <= count);
2367 * If no free blockref could be found we must create an indirect
2368 * block and move a number of blockrefs into it. With the parent
2369 * locked we can safely lock each child in order to delete+duplicate
2370 * it without causing a deadlock.
2372 * This may return the new indirect block or the old parent depending
2373 * on where the key falls. NULL is returned on error.
2375 if (above->live_count == count) {
2376 hammer2_chain_t *nparent;
2378 nparent = hammer2_chain_create_indirect(trans, parent,
2381 if (nparent == NULL) {
2383 hammer2_chain_drop(chain);
2387 if (parent != nparent) {
2388 hammer2_chain_unlock(parent);
2389 parent = *parentp = nparent;
2395 * Link the chain into its parent. Later on we will have to set
2396 * the MOVED bit in situations where we don't mark the new chain
2397 * as being modified.
2399 if (chain->above != NULL)
2400 panic("hammer2: hammer2_chain_create: chain already connected");
2401 KKASSERT(chain->above == NULL);
2402 KKASSERT((chain->flags & HAMMER2_CHAIN_DELETED) == 0);
2403 hammer2_chain_insert(above, NULL, chain,
2404 HAMMER2_CHAIN_INSERT_SPIN |
2405 HAMMER2_CHAIN_INSERT_LIVE);
2409 * Mark the newly created chain modified.
2411 * Device buffers are not instantiated for DATA elements
2412 * as these are handled by logical buffers.
2414 * Indirect and freemap node indirect blocks are handled
2415 * by hammer2_chain_create_indirect() and not by this
2418 * Data for all other bref types is expected to be
2419 * instantiated (INODE, LEAF).
2421 switch(chain->bref.type) {
2422 case HAMMER2_BREF_TYPE_DATA:
2423 hammer2_chain_modify(trans, &chain,
2424 HAMMER2_MODIFY_OPTDATA |
2425 HAMMER2_MODIFY_ASSERTNOCOPY);
2427 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2428 case HAMMER2_BREF_TYPE_INODE:
2429 hammer2_chain_modify(trans, &chain,
2430 HAMMER2_MODIFY_ASSERTNOCOPY);
2434 * Remaining types are not supported by this function.
2435 * In particular, INDIRECT and LEAF_NODE types are
2436 * handled by create_indirect().
2438 panic("hammer2_chain_create: bad type: %d",
2445 * When reconnecting a chain we must set MOVED and setsubmod
2446 * so the flush recognizes that it must update the bref in
2449 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2450 hammer2_chain_ref(chain);
2451 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
2454 hammer2_chain_setsubmod(trans, chain);
2463 * Replace (*chainp) with a duplicate in-memory chain structure which shares
2464 * the same core and media state as the orignal. The original *chainp is
2465 * unlocked and the replacement will be returned locked.
2467 * The old chain may or may not be in a DELETED state. This new chain will
2468 * be live (not deleted).
2470 * The new chain will be marked modified for the current transaction.
2472 * If (parent) is non-NULL then the new duplicated chain is inserted under
2475 * If (parent) is NULL then the new duplicated chain is not inserted anywhere,
2476 * similar to if it had just been chain_alloc()'d (suitable for passing into
2477 * hammer2_chain_create() after this function returns).
2479 * WARNING! This is not a snapshot. Changes made underneath either the old
2480 * or new chain will affect both.
2482 static void hammer2_chain_dup_fixup(hammer2_chain_t *ochain,
2483 hammer2_chain_t *nchain);
2486 hammer2_chain_duplicate(hammer2_trans_t *trans, hammer2_chain_t **parentp,
2487 hammer2_chain_t **chainp, hammer2_blockref_t *bref,
2490 hammer2_mount_t *hmp;
2491 hammer2_chain_t *parent;
2492 hammer2_chain_t *ochain;
2493 hammer2_chain_t *nchain;
2494 hammer2_chain_core_t *above;
2498 * We want nchain to be our go-to live chain, but ochain may be in
2499 * a MODIFIED state within the current flush synchronization segment.
2500 * Force any further modifications of ochain to do another COW
2501 * operation even if modify_tid indicates that one is not needed.
2503 * WARNING! We should never resolve DATA to device buffers
2504 * (XXX allow it if the caller did?), and since
2505 * we currently do not have the logical buffer cache
2506 * buffer in-hand to fix its cached physical offset
2507 * we also force the modify code to not COW it. XXX
2512 ochain->debug_reason += 0x10000;
2514 ochain->debug_reason += 0x100000;
2517 if (ochain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2518 hammer2_chain_modify(trans, &ochain,
2519 HAMMER2_MODIFY_OPTDATA |
2520 HAMMER2_MODIFY_NOREALLOC);
2521 } else if (ochain->flags & HAMMER2_CHAIN_INITIAL) {
2522 hammer2_chain_modify(trans, &ochain,
2523 HAMMER2_MODIFY_OPTDATA);
2525 hammer2_chain_modify(trans, &ochain, 0);
2528 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_FORCECOW);
2531 * Now create a duplicate of the chain structure, associating
2532 * it with the same core, making it the same size, pointing it
2533 * to the same bref (the same media block).
2535 * Give the duplicate the same modify_tid that we previously
2536 * ensured was sufficiently advanced to trigger a block table
2537 * insertion on flush.
2539 * NOTE: bref.mirror_tid duplicated by virtue of bref copy in
2540 * hammer2_chain_alloc()
2543 bref = &ochain->bref;
2545 nchain = hammer2_chain_alloc(hmp, NULL, trans, bref);
2546 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_SNAPSHOT);
2548 nchain = hammer2_chain_alloc(hmp, ochain->pmp, trans, bref);
2550 hammer2_chain_core_alloc(trans, nchain, ochain);
2551 bytes = (hammer2_off_t)1 <<
2552 (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
2553 nchain->bytes = bytes;
2554 nchain->modify_tid = ochain->modify_tid;
2555 if (ochain->flags & HAMMER2_CHAIN_INITIAL)
2556 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_INITIAL);
2559 * Fixup (copy) any embedded data. Non-embedded data relies on the
2560 * media block. We must unlock ochain before we can access nchain's
2561 * media block because they might share the same bp and deadlock if
2564 hammer2_chain_lock(nchain, HAMMER2_RESOLVE_NEVER |
2565 HAMMER2_RESOLVE_NOREF);
2566 hammer2_chain_dup_fixup(ochain, nchain);
2567 /* nchain has 1 ref */
2568 hammer2_chain_unlock(ochain);
2569 KKASSERT((ochain->flags & HAMMER2_CHAIN_EMBEDDED) ||
2570 ochain->data == NULL);
2573 * Place nchain in the modified state, instantiate media data
2574 * if necessary. Because modify_tid is already completely
2575 * synchronized this should not result in a delete-duplicate.
2577 * We want nchain at the target to look like a new insertion.
2578 * Forcing the modification to be INPLACE accomplishes this
2579 * because we get the same nchain with an updated modify_tid.
2581 if (nchain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2582 hammer2_chain_modify(trans, &nchain,
2583 HAMMER2_MODIFY_OPTDATA |
2584 HAMMER2_MODIFY_NOREALLOC |
2585 HAMMER2_MODIFY_INPLACE);
2586 } else if (nchain->flags & HAMMER2_CHAIN_INITIAL) {
2587 hammer2_chain_modify(trans, &nchain,
2588 HAMMER2_MODIFY_OPTDATA |
2589 HAMMER2_MODIFY_INPLACE);
2591 hammer2_chain_modify(trans, &nchain,
2592 HAMMER2_MODIFY_INPLACE);
2596 * If parent is not NULL the duplicated chain will be entered under
2597 * the parent and the MOVED bit set.
2599 * Having both chains locked is extremely important for atomicy.
2601 if (parentp && (parent = *parentp) != NULL) {
2602 above = parent->core;
2603 KKASSERT(ccms_thread_lock_owned(&above->cst));
2604 KKASSERT((nchain->flags & HAMMER2_CHAIN_DELETED) == 0);
2605 KKASSERT(parent->refs > 0);
2607 hammer2_chain_create(trans, parentp, &nchain,
2608 nchain->bref.key, nchain->bref.keybits,
2609 nchain->bref.type, nchain->bytes);
2612 if ((nchain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2613 hammer2_chain_ref(nchain);
2614 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_MOVED);
2616 hammer2_chain_setsubmod(trans, nchain);
2621 * Unconditionally set MOVED to force the parent blockrefs to
2622 * update, and adjust update_hi below nchain so nchain's
2623 * blockrefs are updated with the new attachment.
2625 if (nchain->core->update_hi < trans->sync_tid) {
2626 spin_lock(&nchain->core->cst.spin);
2627 if (nchain->core->update_hi < trans->sync_tid)
2628 nchain->core->update_hi = trans->sync_tid;
2629 spin_unlock(&nchain->core->cst.spin);
2637 * Special in-place delete-duplicate sequence which does not require a
2638 * locked parent. (*chainp) is marked DELETED and atomically replaced
2639 * with a duplicate. Atomicy is at the very-fine spin-lock level in
2640 * order to ensure that lookups do not race us.
2642 * If the old chain is already marked deleted the new chain will also be
2643 * marked deleted. This case can occur when an inode is removed from the
2644 * filesystem but programs still have an open descriptor to it, and during
2645 * flushes when the flush needs to operate on a chain that is deleted in
2646 * the live view but still alive in the flush view.
2648 * The new chain will be marked modified for the current transaction.
2651 hammer2_chain_delete_duplicate(hammer2_trans_t *trans, hammer2_chain_t **chainp,
2654 hammer2_mount_t *hmp;
2655 hammer2_chain_t *ochain;
2656 hammer2_chain_t *nchain;
2657 hammer2_chain_core_t *above;
2660 if (hammer2_debug & 0x20000)
2664 * Note that we do not have to call setsubmod on ochain, calling it
2665 * on nchain is sufficient.
2670 ochain->debug_reason += 0x1000;
2671 if ((ochain->debug_reason & 0xF000) > 0x4000) {
2672 kprintf("ochain %p\n", ochain);
2675 if (ochain->bref.type == HAMMER2_BREF_TYPE_INODE) {
2676 KKASSERT(ochain->data);
2680 * First create a duplicate of the chain structure.
2681 * (nchain is allocated with one ref).
2683 * In the case where nchain inherits ochains core, nchain is
2684 * effectively locked due to ochain being locked (and sharing the
2685 * core), until we can give nchain its own official ock.
2687 nchain = hammer2_chain_alloc(hmp, ochain->pmp, trans, &ochain->bref);
2688 if (flags & HAMMER2_DELDUP_RECORE)
2689 hammer2_chain_core_alloc(trans, nchain, NULL);
2691 hammer2_chain_core_alloc(trans, nchain, ochain);
2692 above = ochain->above;
2694 bytes = (hammer2_off_t)1 <<
2695 (int)(ochain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
2696 nchain->bytes = bytes;
2699 * Duplicate inherits ochain's live state including its modification
2700 * state. This function disposes of the original. Because we are
2701 * doing this in-place under the same parent the block array
2702 * inserted/deleted state does not change.
2704 * The caller isn't expected to make further modifications of ochain
2705 * but set the FORCECOW bit anyway, just in case it does. If ochain
2706 * was previously marked FORCECOW we also flag nchain FORCECOW
2707 * (used during hardlink splits).
2709 * NOTE: bref.mirror_tid duplicated by virtue of bref copy in
2710 * hammer2_chain_alloc()
2712 nchain->data_count += ochain->data_count;
2713 nchain->inode_count += ochain->inode_count;
2714 atomic_set_int(&nchain->flags,
2715 ochain->flags & (HAMMER2_CHAIN_INITIAL |
2716 HAMMER2_CHAIN_FORCECOW));
2717 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_FORCECOW);
2720 * Lock nchain so both chains are now locked (extremely important
2721 * for atomicy). Mark ochain deleted and reinsert into the topology
2722 * and insert nchain all in one go.
2724 * If the ochain is already deleted it is left alone and nchain
2725 * is inserted into the topology as a deleted chain. This is
2726 * important because it allows ongoing operations to be executed
2727 * on a deleted inode which still has open descriptors.
2729 * The deleted case can also occur when a flush delete-duplicates
2730 * a node which is being concurrently modified by ongoing operations
2731 * in a later transaction. This creates a problem because the flush
2732 * is intended to update blockrefs which then propagate, allowing
2733 * the original covering in-memory chains to be freed up. In this
2734 * situation the flush code does NOT free the original covering
2735 * chains and will re-apply them to successive copies.
2737 hammer2_chain_lock(nchain, HAMMER2_RESOLVE_NEVER);
2738 hammer2_chain_dup_fixup(ochain, nchain);
2739 /* extra ref still present from original allocation */
2741 KKASSERT(ochain->flags & HAMMER2_CHAIN_ONRBTREE);
2742 spin_lock(&above->cst.spin);
2743 KKASSERT(ochain->flags & HAMMER2_CHAIN_ONRBTREE);
2746 * Ultimately nchain->modify_tid will be set to trans->sync_tid,
2747 * but we can't do that here because we want to call
2748 * hammer2_chain_modify() to reallocate the block (if necessary).
2750 nchain->modify_tid = ochain->modify_tid;
2752 if (ochain->flags & HAMMER2_CHAIN_DELETED) {
2753 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_DELETED);
2754 if (ochain->delete_tid > trans->sync_tid) {
2756 * delete-duplicate a chain deleted in a later
2757 * transaction. Only allowed on chains created
2758 * before or during the current transaction (flush
2759 * code should filter out chains created after the
2760 * current transaction).
2762 * To make this work is a bit of a hack. We convert
2763 * ochain's delete_tid to the current sync_tid and
2764 * create a nchain which sets up ochains original
2767 * This effectively forces ochain to flush as a
2768 * deletion and nchain as a creation. Thus MOVED
2769 * must be set in ochain (it should already be
2770 * set since it's original delete_tid could not
2771 * have been flushed yet). Since ochain's delete_tid
2772 * has been moved down to sync_tid, a re-flush at
2773 * sync_tid won't try to delete-duplicate ochain
2776 KKASSERT(ochain->modify_tid <= trans->sync_tid);
2777 nchain->delete_tid = ochain->delete_tid;
2778 ochain->delete_tid = trans->sync_tid;
2779 KKASSERT(ochain->flags & HAMMER2_CHAIN_MOVED);
2780 } else if (ochain->delete_tid == trans->sync_tid) {
2782 * ochain was deleted in the current transaction
2784 nchain->delete_tid = trans->sync_tid;
2787 * ochain was deleted in a prior transaction.
2788 * create and delete nchain in the current
2791 nchain->delete_tid = trans->sync_tid;
2793 hammer2_chain_insert(above, ochain->inlayer, nchain, 0);
2795 KKASSERT(trans->sync_tid >= ochain->modify_tid);
2796 ochain->delete_tid = trans->sync_tid;
2797 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_DELETED);
2798 atomic_add_int(&above->live_count, -1);
2799 hammer2_chain_insert(above, NULL, nchain,
2800 HAMMER2_CHAIN_INSERT_LIVE);
2803 if ((ochain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2804 hammer2_chain_ref(ochain);
2805 atomic_set_int(&ochain->flags, HAMMER2_CHAIN_MOVED);
2807 spin_unlock(&above->cst.spin);
2810 * ochain must be unlocked because ochain and nchain might share
2811 * a buffer cache buffer, so we need to release it so nchain can
2812 * potentially obtain it.
2814 hammer2_chain_unlock(ochain);
2817 * Finishing fixing up nchain. A new block will be allocated if
2818 * crossing a synchronization point (meta-data only).
2820 if (nchain->bref.type == HAMMER2_BREF_TYPE_DATA) {
2821 hammer2_chain_modify(trans, &nchain,
2822 HAMMER2_MODIFY_OPTDATA |
2823 HAMMER2_MODIFY_NOREALLOC |
2824 HAMMER2_MODIFY_INPLACE);
2825 } else if (nchain->flags & HAMMER2_CHAIN_INITIAL) {
2826 hammer2_chain_modify(trans, &nchain,
2827 HAMMER2_MODIFY_OPTDATA |
2828 HAMMER2_MODIFY_INPLACE);
2830 hammer2_chain_modify(trans, &nchain,
2831 HAMMER2_MODIFY_INPLACE);
2833 hammer2_chain_drop(nchain);
2836 * Unconditionally set MOVED to force the parent blockrefs to
2837 * update as the chain_modify() above won't necessarily do it.
2839 * Adjust update_hi below nchain so nchain's blockrefs are updated
2840 * with the new attachment.
2842 if ((nchain->flags & HAMMER2_CHAIN_MOVED) == 0) {
2843 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_MOVED);
2844 hammer2_chain_ref(nchain);
2847 if (nchain->core->update_hi < trans->sync_tid) {
2848 spin_lock(&nchain->core->cst.spin);
2849 if (nchain->core->update_hi < trans->sync_tid)
2850 nchain->core->update_hi = trans->sync_tid;
2851 spin_unlock(&nchain->core->cst.spin);
2854 hammer2_chain_setsubmod(trans, nchain);
2859 * Helper function to fixup inodes. The caller procedure stack may hold
2860 * multiple locks on ochain if it represents an inode, preventing our
2861 * unlock from retiring its state to the buffer cache.
2863 * In this situation any attempt to access the buffer cache could result
2864 * either in stale data or a deadlock. Work around the problem by copying
2865 * the embedded data directly.
2869 hammer2_chain_dup_fixup(hammer2_chain_t *ochain, hammer2_chain_t *nchain)
2871 if (ochain->data == NULL)
2873 switch(ochain->bref.type) {
2874 case HAMMER2_BREF_TYPE_INODE:
2875 KKASSERT(nchain->data == NULL);
2876 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_EMBEDDED);
2877 nchain->data = kmalloc(sizeof(nchain->data->ipdata),
2878 ochain->hmp->mchain, M_WAITOK | M_ZERO);
2879 nchain->data->ipdata = ochain->data->ipdata;
2881 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
2882 KKASSERT(nchain->data == NULL);
2883 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_EMBEDDED);
2884 nchain->data = kmalloc(sizeof(nchain->data->bmdata),
2885 ochain->hmp->mchain, M_WAITOK | M_ZERO);
2886 bcopy(ochain->data->bmdata,
2887 nchain->data->bmdata,
2888 sizeof(nchain->data->bmdata));
2896 * Create a snapshot of the specified {parent, ochain} with the specified
2897 * label. The originating hammer2_inode must be exclusively locked for
2900 * The ioctl code has already synced the filesystem.
2903 hammer2_chain_snapshot(hammer2_trans_t *trans, hammer2_chain_t **ochainp,
2904 hammer2_ioc_pfs_t *pfs)
2906 hammer2_mount_t *hmp;
2907 hammer2_chain_t *ochain = *ochainp;
2908 hammer2_chain_t *nchain;
2909 hammer2_inode_data_t *ipdata;
2910 hammer2_inode_t *nip;
2917 kprintf("snapshot %s ochain->refs %d ochain->flags %08x\n",
2918 pfs->name, ochain->refs, ochain->flags);
2920 name_len = strlen(pfs->name);
2921 lhc = hammer2_dirhash(pfs->name, name_len);
2924 opfs_clid = ochain->data->ipdata.pfs_clid;
2929 * Create the snapshot directory under the super-root
2931 * Set PFS type, generate a unique filesystem id, and generate
2932 * a cluster id. Use the same clid when snapshotting a PFS root,
2933 * which theoretically allows the snapshot to be used as part of
2934 * the same cluster (perhaps as a cache).
2936 * Copy the (flushed) ochain's blockref array. Theoretically we
2937 * could use chain_duplicate() but it becomes difficult to disentangle
2938 * the shared core so for now just brute-force it.
2944 nip = hammer2_inode_create(trans, hmp->sroot, &vat, proc0.p_ucred,
2945 pfs->name, name_len, &nchain, &error);
2948 ipdata = hammer2_chain_modify_ip(trans, nip, &nchain, 0);
2949 ipdata->pfs_type = HAMMER2_PFSTYPE_SNAPSHOT;
2950 kern_uuidgen(&ipdata->pfs_fsid, 1);
2951 if (ochain->flags & HAMMER2_CHAIN_PFSROOT)
2952 ipdata->pfs_clid = opfs_clid;
2954 kern_uuidgen(&ipdata->pfs_clid, 1);
2955 atomic_set_int(&nchain->flags, HAMMER2_CHAIN_PFSROOT);
2956 ipdata->u.blockset = ochain->data->ipdata.u.blockset;
2958 hammer2_inode_unlock_ex(nip, nchain);
2964 * Create an indirect block that covers one or more of the elements in the
2965 * current parent. Either returns the existing parent with no locking or
2966 * ref changes or returns the new indirect block locked and referenced
2967 * and leaving the original parent lock/ref intact as well.
2969 * If an error occurs, NULL is returned and *errorp is set to the error.
2971 * The returned chain depends on where the specified key falls.
2973 * The key/keybits for the indirect mode only needs to follow three rules:
2975 * (1) That all elements underneath it fit within its key space and
2977 * (2) That all elements outside it are outside its key space.
2979 * (3) When creating the new indirect block any elements in the current
2980 * parent that fit within the new indirect block's keyspace must be
2981 * moved into the new indirect block.
2983 * (4) The keyspace chosen for the inserted indirect block CAN cover a wider
2984 * keyspace the the current parent, but lookup/iteration rules will
2985 * ensure (and must ensure) that rule (2) for all parents leading up
2986 * to the nearest inode or the root volume header is adhered to. This
2987 * is accomplished by always recursing through matching keyspaces in
2988 * the hammer2_chain_lookup() and hammer2_chain_next() API.
2990 * The current implementation calculates the current worst-case keyspace by
2991 * iterating the current parent and then divides it into two halves, choosing
2992 * whichever half has the most elements (not necessarily the half containing
2993 * the requested key).
2995 * We can also opt to use the half with the least number of elements. This
2996 * causes lower-numbered keys (aka logical file offsets) to recurse through
2997 * fewer indirect blocks and higher-numbered keys to recurse through more.
2998 * This also has the risk of not moving enough elements to the new indirect
2999 * block and being forced to create several indirect blocks before the element
3002 * Must be called with an exclusively locked parent.
3004 static int hammer2_chain_indkey_freemap(hammer2_chain_t *parent,
3005 hammer2_key_t *keyp, int keybits,
3006 hammer2_blockref_t *base, int count);
3007 static int hammer2_chain_indkey_normal(hammer2_chain_t *parent,
3008 hammer2_key_t *keyp, int keybits,
3009 hammer2_blockref_t *base, int count);
3012 hammer2_chain_create_indirect(hammer2_trans_t *trans, hammer2_chain_t *parent,
3013 hammer2_key_t create_key, int create_bits,
3014 int for_type, int *errorp)
3016 hammer2_mount_t *hmp;
3017 hammer2_chain_core_t *above;
3018 hammer2_chain_core_t *icore;
3019 hammer2_blockref_t *base;
3020 hammer2_blockref_t *bref;
3021 hammer2_blockref_t bcopy;
3022 hammer2_chain_t *chain;
3023 hammer2_chain_t *ichain;
3024 hammer2_chain_t dummy;
3025 hammer2_key_t key = create_key;
3026 hammer2_key_t key_beg;
3027 hammer2_key_t key_end;
3028 hammer2_key_t key_next;
3029 int keybits = create_bits;
3036 * Calculate the base blockref pointer or NULL if the chain
3037 * is known to be empty. We need to calculate the array count
3038 * for RB lookups either way.
3042 KKASSERT(ccms_thread_lock_owned(&parent->core->cst));
3043 above = parent->core;
3045 /*hammer2_chain_modify(trans, &parent, HAMMER2_MODIFY_OPTDATA);*/
3046 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
3049 switch(parent->bref.type) {
3050 case HAMMER2_BREF_TYPE_INODE:
3051 count = HAMMER2_SET_COUNT;
3053 case HAMMER2_BREF_TYPE_INDIRECT:
3054 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3055 count = parent->bytes / sizeof(hammer2_blockref_t);
3057 case HAMMER2_BREF_TYPE_VOLUME:
3058 count = HAMMER2_SET_COUNT;
3060 case HAMMER2_BREF_TYPE_FREEMAP:
3061 count = HAMMER2_SET_COUNT;
3064 panic("hammer2_chain_create_indirect: "
3065 "unrecognized blockref type: %d",
3071 switch(parent->bref.type) {
3072 case HAMMER2_BREF_TYPE_INODE:
3073 base = &parent->data->ipdata.u.blockset.blockref[0];
3074 count = HAMMER2_SET_COUNT;
3076 case HAMMER2_BREF_TYPE_INDIRECT:
3077 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3078 base = &parent->data->npdata[0];
3079 count = parent->bytes / sizeof(hammer2_blockref_t);
3081 case HAMMER2_BREF_TYPE_VOLUME:
3082 base = &hmp->voldata.sroot_blockset.blockref[0];
3083 count = HAMMER2_SET_COUNT;
3085 case HAMMER2_BREF_TYPE_FREEMAP:
3086 base = &hmp->voldata.freemap_blockset.blockref[0];
3087 count = HAMMER2_SET_COUNT;
3090 panic("hammer2_chain_create_indirect: "
3091 "unrecognized blockref type: %d",
3099 * dummy used in later chain allocation (no longer used for lookups).
3101 bzero(&dummy, sizeof(dummy));
3102 dummy.delete_tid = HAMMER2_MAX_TID;
3105 * When creating an indirect block for a freemap node or leaf
3106 * the key/keybits must be fitted to static radix levels because
3107 * particular radix levels use particular reserved blocks in the
3110 * This routine calculates the key/radix of the indirect block
3111 * we need to create, and whether it is on the high-side or the
3114 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
3115 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
3116 keybits = hammer2_chain_indkey_freemap(parent, &key, keybits,
3119 keybits = hammer2_chain_indkey_normal(parent, &key, keybits,
3124 * Normalize the key for the radix being represented, keeping the
3125 * high bits and throwing away the low bits.
3127 key &= ~(((hammer2_key_t)1 << keybits) - 1);
3130 * How big should our new indirect block be? It has to be at least
3131 * as large as its parent.
3133 if (parent->bref.type == HAMMER2_BREF_TYPE_INODE)
3134 nbytes = HAMMER2_IND_BYTES_MIN;
3136 nbytes = HAMMER2_IND_BYTES_MAX;
3137 if (nbytes < count * sizeof(hammer2_blockref_t))
3138 nbytes = count * sizeof(hammer2_blockref_t);
3141 * Ok, create our new indirect block
3143 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
3144 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
3145 dummy.bref.type = HAMMER2_BREF_TYPE_FREEMAP_NODE;
3147 dummy.bref.type = HAMMER2_BREF_TYPE_INDIRECT;
3149 dummy.bref.key = key;
3150 dummy.bref.keybits = keybits;
3151 dummy.bref.data_off = hammer2_getradix(nbytes);
3152 dummy.bref.methods = parent->bref.methods;
3154 ichain = hammer2_chain_alloc(hmp, parent->pmp, trans, &dummy.bref);
3155 atomic_set_int(&ichain->flags, HAMMER2_CHAIN_INITIAL);
3156 hammer2_chain_core_alloc(trans, ichain, NULL);
3157 icore = ichain->core;
3158 hammer2_chain_lock(ichain, HAMMER2_RESOLVE_MAYBE);
3159 hammer2_chain_drop(ichain); /* excess ref from alloc */
3162 * We have to mark it modified to allocate its block, but use
3163 * OPTDATA to allow it to remain in the INITIAL state. Otherwise
3164 * it won't be acted upon by the flush code.
3166 * XXX leave the node unmodified, depend on the update_hi
3167 * flush to assign and modify parent blocks.
3169 hammer2_chain_modify(trans, &ichain, HAMMER2_MODIFY_OPTDATA);
3172 * Iterate the original parent and move the matching brefs into
3173 * the new indirect block.
3175 * XXX handle flushes.
3178 key_end = HAMMER2_MAX_KEY;
3180 spin_lock(&above->cst.spin);
3184 if (++loops > 8192) {
3185 spin_unlock(&above->cst.spin);
3186 panic("shit parent=%p base/count %p:%d\n",
3187 parent, base, count);
3191 * NOTE: spinlock stays intact, returned chain (if not NULL)
3192 * is not referenced or locked.
3194 chain = hammer2_combined_find(parent, base, count,
3195 &cache_index, &key_next,
3200 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3201 if (key_next == 0 || key_next > key_end)
3208 * Use the full live (not deleted) element for the scan
3209 * iteration. HAMMER2 does not allow partial replacements.
3211 * XXX should be built into hammer2_combined_find().
3213 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3216 * Skip keys that are not within the key/radix of the new
3217 * indirect block. They stay in the parent.
3219 if ((~(((hammer2_key_t)1 << keybits) - 1) &
3220 (key ^ bref->key)) != 0) {
3221 if (key_next == 0 || key_next > key_end)
3228 * Load the new indirect block by acquiring or allocating
3229 * the related chain, then move it to the new parent (ichain)
3230 * via DELETE-DUPLICATE.
3232 * WARNING! above->cst.spin must be held when parent is
3233 * modified, even though we own the full blown lock,
3234 * to deal with setsubmod and rename races.
3235 * (XXX remove this req).
3239 * Use chain already present in the RBTREE
3241 hammer2_chain_ref(chain);
3242 spin_unlock(&above->cst.spin);
3243 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER |
3244 HAMMER2_RESOLVE_NOREF);
3247 * Get chain for blockref element. _get returns NULL
3248 * on insertion race.
3251 spin_unlock(&above->cst.spin);
3252 chain = hammer2_chain_get(parent, bref);
3255 if (bcmp(&bcopy, bref, sizeof(bcopy))) {
3256 hammer2_chain_drop(chain);
3259 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER |
3260 HAMMER2_RESOLVE_NOREF);
3262 hammer2_chain_delete(trans, chain, HAMMER2_DELETE_WILLDUP);
3263 hammer2_chain_duplicate(trans, &ichain, &chain, NULL, 0);
3264 hammer2_chain_unlock(chain);
3265 KKASSERT(parent->refs > 0);
3267 spin_lock(&above->cst.spin);
3268 if (key_next == 0 || key_next > key_end)
3272 spin_unlock(&above->cst.spin);
3275 * Insert the new indirect block into the parent now that we've
3276 * cleared out some entries in the parent. We calculated a good
3277 * insertion index in the loop above (ichain->index).
3279 * We don't have to set MOVED here because we mark ichain modified
3280 * down below (so the normal modified -> flush -> set-moved sequence
3283 * The insertion shouldn't race as this is a completely new block
3284 * and the parent is locked.
3286 KKASSERT((ichain->flags & HAMMER2_CHAIN_ONRBTREE) == 0);
3287 hammer2_chain_insert(above, NULL, ichain,
3288 HAMMER2_CHAIN_INSERT_SPIN |
3289 HAMMER2_CHAIN_INSERT_LIVE);
3292 * Mark the new indirect block modified after insertion, which
3293 * will propagate up through parent all the way to the root and
3294 * also allocate the physical block in ichain for our caller,
3295 * and assign ichain->data to a pre-zero'd space (because there
3296 * is not prior data to copy into it).
3298 * We have to set update_hi in ichain's flags manually so the
3299 * flusher knows it has to recurse through it to get to all of
3300 * our moved blocks, then call setsubmod() to set the bit
3303 /*hammer2_chain_modify(trans, &ichain, HAMMER2_MODIFY_OPTDATA);*/
3304 if (ichain->core->update_hi < trans->sync_tid) {
3305 spin_lock(&ichain->core->cst.spin);
3306 if (ichain->core->update_hi < trans->sync_tid)
3307 ichain->core->update_hi = trans->sync_tid;
3308 spin_unlock(&ichain->core->cst.spin);
3310 hammer2_chain_setsubmod(trans, ichain);
3313 * Figure out what to return.
3315 if (~(((hammer2_key_t)1 << keybits) - 1) &
3316 (create_key ^ key)) {
3318 * Key being created is outside the key range,
3319 * return the original parent.
3321 hammer2_chain_unlock(ichain);
3324 * Otherwise its in the range, return the new parent.
3325 * (leave both the new and old parent locked).
3334 * Calculate the keybits and highside/lowside of the freemap node the
3335 * caller is creating.
3337 * This routine will specify the next higher-level freemap key/radix
3338 * representing the lowest-ordered set. By doing so, eventually all
3339 * low-ordered sets will be moved one level down.
3341 * We have to be careful here because the freemap reserves a limited
3342 * number of blocks for a limited number of levels. So we can't just
3343 * push indiscriminately.
3346 hammer2_chain_indkey_freemap(hammer2_chain_t *parent, hammer2_key_t *keyp,
3347 int keybits, hammer2_blockref_t *base, int count)
3349 hammer2_chain_core_t *above;
3350 hammer2_chain_t *chain;
3351 hammer2_blockref_t *bref;
3353 hammer2_key_t key_beg;
3354 hammer2_key_t key_end;
3355 hammer2_key_t key_next;
3362 above = parent->core;
3368 * Calculate the range of keys in the array being careful to skip
3369 * slots which are overridden with a deletion.
3372 key_end = HAMMER2_MAX_KEY;
3374 spin_lock(&above->cst.spin);
3377 if (++loops == 100000) {
3378 panic("indkey_freemap shit %p %p:%d\n",
3379 parent, base, count);
3381 chain = hammer2_combined_find(parent, base, count,
3382 &cache_index, &key_next,
3383 key_beg, key_end, &bref);
3390 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3391 if (key_next == 0 || key_next > key_end)
3398 * Use the full live (not deleted) element for the scan
3399 * iteration. HAMMER2 does not allow partial replacements.
3401 * XXX should be built into hammer2_combined_find().
3403 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3405 if (keybits > bref->keybits) {
3407 keybits = bref->keybits;
3408 } else if (keybits == bref->keybits && bref->key < key) {
3415 spin_unlock(&above->cst.spin);
3418 * Return the keybits for a higher-level FREEMAP_NODE covering
3422 case HAMMER2_FREEMAP_LEVEL0_RADIX:
3423 keybits = HAMMER2_FREEMAP_LEVEL1_RADIX;
3425 case HAMMER2_FREEMAP_LEVEL1_RADIX:
3426 keybits = HAMMER2_FREEMAP_LEVEL2_RADIX;
3428 case HAMMER2_FREEMAP_LEVEL2_RADIX:
3429 keybits = HAMMER2_FREEMAP_LEVEL3_RADIX;
3431 case HAMMER2_FREEMAP_LEVEL3_RADIX:
3432 keybits = HAMMER2_FREEMAP_LEVEL4_RADIX;
3434 case HAMMER2_FREEMAP_LEVEL4_RADIX:
3435 panic("hammer2_chain_indkey_freemap: level too high");
3438 panic("hammer2_chain_indkey_freemap: bad radix");
3447 * Calculate the keybits and highside/lowside of the indirect block the
3448 * caller is creating.
3451 hammer2_chain_indkey_normal(hammer2_chain_t *parent, hammer2_key_t *keyp,
3452 int keybits, hammer2_blockref_t *base, int count)
3454 hammer2_chain_core_t *above;
3455 hammer2_blockref_t *bref;
3456 hammer2_chain_t *chain;
3457 hammer2_key_t key_beg;
3458 hammer2_key_t key_end;
3459 hammer2_key_t key_next;
3468 above = parent->core;
3473 * Calculate the range of keys in the array being careful to skip
3474 * slots which are overridden with a deletion. Once the scan
3475 * completes we will cut the key range in half and shift half the
3476 * range into the new indirect block.
3479 key_end = HAMMER2_MAX_KEY;
3481 spin_lock(&above->cst.spin);
3484 if (++loops == 100000) {
3485 panic("indkey_freemap shit %p %p:%d\n",
3486 parent, base, count);
3488 chain = hammer2_combined_find(parent, base, count,
3489 &cache_index, &key_next,
3490 key_beg, key_end, &bref);
3497 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3498 if (key_next == 0 || key_next > key_end)
3505 * Use the full live (not deleted) element for the scan
3506 * iteration. HAMMER2 does not allow partial replacements.
3508 * XXX should be built into hammer2_combined_find().
3510 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
3513 * Expand our calculated key range (key, keybits) to fit
3514 * the scanned key. nkeybits represents the full range
3515 * that we will later cut in half (two halves @ nkeybits - 1).
3518 if (nkeybits < bref->keybits) {
3519 if (bref->keybits > 64) {
3520 kprintf("bad bref chain %p bref %p\n",
3524 nkeybits = bref->keybits;
3526 while (nkeybits < 64 &&
3527 (~(((hammer2_key_t)1 << nkeybits) - 1) &
3528 (key ^ bref->key)) != 0) {
3533 * If the new key range is larger we have to determine
3534 * which side of the new key range the existing keys fall
3535 * under by checking the high bit, then collapsing the
3536 * locount into the hicount or vise-versa.
3538 if (keybits != nkeybits) {
3539 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) {
3550 * The newly scanned key will be in the lower half or the
3551 * upper half of the (new) key range.
3553 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key)
3562 spin_unlock(&above->cst.spin);
3563 bref = NULL; /* now invalid (safety) */
3566 * Adjust keybits to represent half of the full range calculated
3567 * above (radix 63 max)
3572 * Select whichever half contains the most elements. Theoretically
3573 * we can select either side as long as it contains at least one
3574 * element (in order to ensure that a free slot is present to hold
3575 * the indirect block).
3577 if (hammer2_indirect_optimize) {
3579 * Insert node for least number of keys, this will arrange
3580 * the first few blocks of a large file or the first few
3581 * inodes in a directory with fewer indirect blocks when
3584 if (hicount < locount && hicount != 0)
3585 key |= (hammer2_key_t)1 << keybits;
3587 key &= ~(hammer2_key_t)1 << keybits;
3590 * Insert node for most number of keys, best for heavily
3593 if (hicount > locount)
3594 key |= (hammer2_key_t)1 << keybits;
3596 key &= ~(hammer2_key_t)1 << keybits;
3604 * Sets CHAIN_DELETED and CHAIN_MOVED in the chain being deleted and
3605 * set chain->delete_tid. The chain is not actually marked possibly-free
3606 * in the freemap until the deletion is completely flushed out (because
3607 * a flush which doesn't cover the entire deletion is flushing the deleted
3608 * chain as if it were live).
3610 * This function does NOT generate a modification to the parent. It
3611 * would be nearly impossible to figure out which parent to modify anyway.
3612 * Such modifications are handled top-down by the flush code and are
3613 * properly merged using the flush synchronization point.
3615 * The find/get code will properly overload the RBTREE check on top of
3616 * the bref check to detect deleted entries.
3618 * This function is NOT recursive. Any entity already pushed into the
3619 * chain (such as an inode) may still need visibility into its contents,
3620 * as well as the ability to read and modify the contents. For example,
3621 * for an unlinked file which is still open.
3623 * NOTE: This function does NOT set chain->modify_tid, allowing future
3624 * code to distinguish between live and deleted chains by testing
3625 * trans->sync_tid vs chain->modify_tid and chain->delete_tid.
3627 * NOTE: Deletions normally do not occur in the middle of a duplication
3628 * chain but we use a trick for hardlink migration that refactors
3629 * the originating inode without deleting it, so we make no assumptions
3633 hammer2_chain_delete(hammer2_trans_t *trans, hammer2_chain_t *chain, int flags)
3635 KKASSERT(ccms_thread_lock_owned(&chain->core->cst));
3638 * Nothing to do if already marked.
3640 if (chain->flags & HAMMER2_CHAIN_DELETED)
3644 * The setting of DELETED causes finds, lookups, and _next iterations
3645 * to no longer recognize the chain. RB_SCAN()s will still have
3646 * visibility (needed for flush serialization points).
3648 * We need the spinlock on the core whos RBTREE contains chain
3649 * to protect against races.
3651 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
3652 spin_lock(&chain->above->cst.spin);
3654 KKASSERT(trans->sync_tid >= chain->modify_tid);
3655 chain->delete_tid = trans->sync_tid;
3656 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3657 atomic_add_int(&chain->above->live_count, -1);
3658 ++chain->above->generation;
3661 * We must set MOVED along with DELETED for the flush code to
3662 * recognize the operation and properly disconnect the chain
3665 if ((chain->flags & HAMMER2_CHAIN_MOVED) == 0) {
3666 hammer2_chain_ref(chain);
3667 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MOVED);
3669 spin_unlock(&chain->above->cst.spin);
3671 if (flags & HAMMER2_DELETE_WILLDUP)
3672 atomic_set_int(&chain->flags, HAMMER2_CHAIN_FORCECOW);
3674 hammer2_chain_setsubmod(trans, chain);
3678 * Called with the core spinlock held to check for freeable layers.
3679 * Used by the flush code. Layers can wind up not being freed due
3680 * to the temporary layer->refs count. This function frees up any
3681 * layers that were missed.
3684 hammer2_chain_layer_check_locked(hammer2_mount_t *hmp,
3685 hammer2_chain_core_t *core)
3687 hammer2_chain_layer_t *layer;
3688 hammer2_chain_layer_t *tmp;
3690 tmp = TAILQ_FIRST(&core->layerq);
3691 while ((layer = tmp) != NULL) {
3692 tmp = TAILQ_NEXT(tmp, entry);
3693 if (layer->refs == 0 && RB_EMPTY(&layer->rbtree)) {
3694 TAILQ_REMOVE(&core->layerq, layer, entry);
3697 spin_unlock(&core->cst.spin);
3698 kfree(layer, hmp->mchain);
3699 spin_lock(&core->cst.spin);
3707 * Returns the index of the nearest element in the blockref array >= elm.
3708 * Returns (count) if no element could be found.
3710 * Sets *key_nextp to the next key for loop purposes but does not modify
3711 * it if the next key would be higher than the current value of *key_nextp.
3712 * Note that *key_nexp can overflow to 0, which should be tested by the
3715 * (*cache_indexp) is a heuristic and can be any value without effecting
3718 * The spin lock on the related chain must be held.
3721 hammer2_base_find(hammer2_chain_t *chain,
3722 hammer2_blockref_t *base, int count,
3723 int *cache_indexp, hammer2_key_t *key_nextp,
3724 hammer2_key_t key_beg, hammer2_key_t key_end)
3726 hammer2_chain_core_t *core = chain->core;
3727 hammer2_blockref_t *scan;
3728 hammer2_key_t scan_end;
3734 KKASSERT(core->flags & HAMMER2_CORE_COUNTEDBREFS);
3735 if (count == 0 || base == NULL)
3739 * Sequential optimization
3743 if (i >= core->live_zero)
3744 i = core->live_zero - 1;
3747 KKASSERT(i < count);
3753 while (i > 0 && (scan->type == 0 || scan->key > key_beg)) {
3760 * Search forwards, stop when we find a scan element which
3761 * encloses the key or until we know that there are no further
3765 if (scan->type != 0) {
3766 if (scan->key > key_beg)
3768 scan_end = scan->key +
3769 ((hammer2_key_t)1 << scan->keybits) - 1;
3770 if (scan_end >= key_beg)
3773 if (i >= core->live_zero)
3780 if (i >= core->live_zero) {
3783 scan_end = scan->key +
3784 ((hammer2_key_t)1 << scan->keybits);
3785 if (scan_end && (*key_nextp > scan_end ||
3787 *key_nextp = scan_end;
3795 * Do a combined search and return the next match either from the blockref
3796 * array or from the in-memory chain. Sets *bresp to the returned bref in
3797 * both cases, or sets it to NULL if the search exhausted. Only returns
3798 * a non-NULL chain if the search matched from the in-memory chain.
3800 * Must be called with above's spinlock held. Spinlock remains held
3801 * through the operation.
3803 * The returned chain is not locked or referenced. Use the returned bref
3804 * to determine if the search exhausted or not.
3806 static hammer2_chain_t *
3807 hammer2_combined_find(hammer2_chain_t *parent,
3808 hammer2_blockref_t *base, int count,
3809 int *cache_indexp, hammer2_key_t *key_nextp,
3810 hammer2_key_t key_beg, hammer2_key_t key_end,
3811 hammer2_blockref_t **bresp)
3813 hammer2_blockref_t *bref;
3814 hammer2_chain_t *chain;
3817 *key_nextp = key_end + 1;
3818 i = hammer2_base_find(parent, base, count, cache_indexp,
3819 key_nextp, key_beg, key_end);
3820 chain = hammer2_chain_find(parent, key_nextp, key_beg, key_end);
3825 if (i == count && chain == NULL) {
3827 return(chain); /* NULL */
3831 * Only chain matched
3834 bref = &chain->bref;
3839 * Only blockref matched.
3841 if (chain == NULL) {
3847 * Both in-memory and blockref match.
3849 * If they are both flush with the left hand side select the chain.
3850 * If their starts match select the chain.
3851 * Otherwise the nearer element wins.
3853 if (chain->bref.key <= key_beg && base[i].key <= key_beg) {
3854 bref = &chain->bref;
3857 if (chain->bref.key <= base[i].key) {
3858 bref = &chain->bref;
3866 * If the bref is out of bounds we've exhausted our search.
3869 if (bref->key > key_end) {
3879 * Locate the specified block array element and delete it. The element
3882 * The spin lock on the related chain must be held.
3884 * NOTE: live_count was adjusted when the chain was deleted, so it does not
3885 * need to be adjusted when we commit the media change.
3888 hammer2_base_delete(hammer2_chain_t *chain,
3889 hammer2_blockref_t *base, int count,
3890 int *cache_indexp, hammer2_chain_t *child)
3892 hammer2_blockref_t *elm = &child->bref;
3893 hammer2_chain_core_t *core = chain->core;
3894 hammer2_key_t key_next;
3898 * Delete element. Expect the element to exist.
3900 * XXX see caller, flush code not yet sophisticated enough to prevent
3901 * re-flushed in some cases.
3903 key_next = 0; /* max range */
3904 i = hammer2_base_find(chain, base, count, cache_indexp,
3905 &key_next, elm->key, elm->key);
3906 if (i == count || base[i].type == 0 ||
3907 base[i].key != elm->key || base[i].keybits != elm->keybits) {
3908 panic("delete base %p element not found at %d/%d elm %p\n",
3909 base, i, count, elm);
3912 bzero(&base[i], sizeof(*base));
3913 if (core->live_zero == i + 1) {
3914 while (--i >= 0 && base[i].type == 0)
3916 core->live_zero = i + 1;
3921 * Insert the specified element. The block array must not already have the
3922 * element and must have space available for the insertion.
3924 * The spin lock on the related chain must be held.
3926 * NOTE: live_count was adjusted when the chain was deleted, so it does not
3927 * need to be adjusted when we commit the media change.
3930 hammer2_base_insert(hammer2_chain_t *parent,
3931 hammer2_blockref_t *base, int count,
3932 int *cache_indexp, hammer2_chain_t *child)
3934 hammer2_blockref_t *elm = &child->bref;
3935 hammer2_chain_core_t *core = parent->core;
3936 hammer2_key_t key_next;
3945 * Insert new element. Expect the element to not already exist
3946 * unless we are replacing it.
3948 * XXX see caller, flush code not yet sophisticated enough to prevent
3949 * re-flushed in some cases.
3951 key_next = 0; /* max range */
3952 i = hammer2_base_find(parent, base, count, cache_indexp,
3953 &key_next, elm->key, elm->key);
3956 * Shortcut fill optimization, typical ordered insertion(s) may not
3959 KKASSERT(i >= 0 && i <= count);
3961 if (i == count && core->live_zero < count) {
3962 i = core->live_zero++;
3967 xkey = elm->key + ((hammer2_key_t)1 << elm->keybits) - 1;
3968 if (i != count && (base[i].key < elm->key || xkey >= base[i].key)) {
3969 panic("insert base %p overlapping elements at %d elm %p\n",
3974 * Try to find an empty slot before or after.
3978 while (j > 0 || k < count) {
3980 if (j >= 0 && base[j].type == 0) {
3984 bcopy(&base[j+1], &base[j],
3985 (i - j - 1) * sizeof(*base));
3991 if (k < count && base[k].type == 0) {
3992 bcopy(&base[i], &base[i+1],
3993 (k - i) * sizeof(hammer2_blockref_t));
3995 if (core->live_zero <= k)
3996 core->live_zero = k + 1;
4001 panic("hammer2_base_insert: no room!");
4008 for (l = 0; l < count; ++l) {
4010 key_next = base[l].key +
4011 ((hammer2_key_t)1 << base[l].keybits) - 1;
4015 while (++l < count) {
4017 if (base[l].key <= key_next)
4018 panic("base_insert %d %d,%d,%d fail %p:%d", u, i, j, k, base, l);
4019 key_next = base[l].key +
4020 ((hammer2_key_t)1 << base[l].keybits) - 1;
4030 * Sort the blockref array for the chain. Used by the flush code to
4031 * sort the blockref[] array.
4033 * The chain must be exclusively locked AND spin-locked.
4035 typedef hammer2_blockref_t *hammer2_blockref_p;
4039 hammer2_base_sort_callback(const void *v1, const void *v2)
4041 hammer2_blockref_p bref1 = *(const hammer2_blockref_p *)v1;
4042 hammer2_blockref_p bref2 = *(const hammer2_blockref_p *)v2;
4045 * Make sure empty elements are placed at the end of the array
4047 if (bref1->type == 0) {
4048 if (bref2->type == 0)
4051 } else if (bref2->type == 0) {
4058 if (bref1->key < bref2->key)
4060 if (bref1->key > bref2->key)
4066 hammer2_base_sort(hammer2_chain_t *chain)
4068 hammer2_blockref_t *base;
4071 switch(chain->bref.type) {
4072 case HAMMER2_BREF_TYPE_INODE:
4074 * Special shortcut for embedded data returns the inode
4075 * itself. Callers must detect this condition and access
4076 * the embedded data (the strategy code does this for us).
4078 * This is only applicable to regular files and softlinks.
4080 if (chain->data->ipdata.op_flags & HAMMER2_OPFLAG_DIRECTDATA)
4082 base = &chain->data->ipdata.u.blockset.blockref[0];
4083 count = HAMMER2_SET_COUNT;
4085 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4086 case HAMMER2_BREF_TYPE_INDIRECT:
4088 * Optimize indirect blocks in the INITIAL state to avoid
4091 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) == 0);
4092 base = &chain->data->npdata[0];
4093 count = chain->bytes / sizeof(hammer2_blockref_t);
4095 case HAMMER2_BREF_TYPE_VOLUME:
4096 base = &chain->hmp->voldata.sroot_blockset.blockref[0];
4097 count = HAMMER2_SET_COUNT;
4099 case HAMMER2_BREF_TYPE_FREEMAP:
4100 base = &chain->hmp->voldata.freemap_blockset.blockref[0];
4101 count = HAMMER2_SET_COUNT;
4104 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
4106 base = NULL; /* safety */
4107 count = 0; /* safety */
4109 kqsort(base, count, sizeof(*base), hammer2_base_sort_callback);
4115 * Chain memory management
4118 hammer2_chain_wait(hammer2_chain_t *chain)
4120 tsleep(chain, 0, "chnflw", 1);
4124 * Manage excessive memory resource use for chain and related
4128 hammer2_chain_memory_wait(hammer2_pfsmount_t *pmp)
4131 while (pmp->inmem_chains > desiredvnodes / 10 &&
4132 pmp->inmem_chains > pmp->mp->mnt_nvnodelistsize * 2) {
4134 speedup_syncer(pmp->mp);
4135 pmp->inmem_waiting = 1;
4136 tsleep(&pmp->inmem_waiting, 0, "chnmem", hz);
4140 if (pmp->inmem_chains > desiredvnodes / 10 &&
4141 pmp->inmem_chains > pmp->mp->mnt_nvnodelistsize * 7 / 4) {
4142 speedup_syncer(pmp->mp);
4148 hammer2_chain_memory_wakeup(hammer2_pfsmount_t *pmp)
4150 if (pmp->inmem_waiting &&
4151 (pmp->inmem_chains <= desiredvnodes / 10 ||
4152 pmp->inmem_chains <= pmp->mp->mnt_nvnodelistsize * 2)) {
4154 pmp->inmem_waiting = 0;
4155 wakeup(&pmp->inmem_waiting);
4161 adjreadcounter(hammer2_blockref_t *bref, size_t bytes)
4165 switch(bref->type) {
4166 case HAMMER2_BREF_TYPE_DATA:
4167 counterp = &hammer2_iod_file_read;
4169 case HAMMER2_BREF_TYPE_INODE:
4170 counterp = &hammer2_iod_meta_read;
4172 case HAMMER2_BREF_TYPE_INDIRECT:
4173 counterp = &hammer2_iod_indr_read;
4175 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4176 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
4177 counterp = &hammer2_iod_fmap_read;
4180 counterp = &hammer2_iod_volu_read;