2 * Copyright (c) 2011-2018 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 * and 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 * Chains are no-longer delete-duplicated. Instead, the original in-memory
44 * chain will be moved along with its block reference (e.g. for things like
45 * renames, hardlink operations, modifications, etc), and will be indexed
46 * on a secondary list for flush handling instead of propagating a flag
49 * Concurrent front-end operations can still run against backend flushes
50 * as long as they do not cross the current flush boundary. An operation
51 * running above the current flush (in areas not yet flushed) can become
52 * part of the current flush while ano peration running below the current
53 * flush can become part of the next flush.
55 #include <sys/cdefs.h>
56 #include <sys/param.h>
57 #include <sys/systm.h>
58 #include <sys/types.h>
60 #include <sys/kern_syscall.h>
63 #include <crypto/sha2/sha2.h>
67 static hammer2_chain_t *hammer2_chain_create_indirect(
68 hammer2_chain_t *parent,
69 hammer2_key_t key, int keybits,
70 hammer2_tid_t mtid, int for_type, int *errorp);
71 static void hammer2_chain_rename_obref(hammer2_chain_t **parentp,
72 hammer2_chain_t *chain, hammer2_tid_t mtid,
73 int flags, hammer2_blockref_t *obref);
74 static int hammer2_chain_delete_obref(hammer2_chain_t *parent,
75 hammer2_chain_t *chain,
76 hammer2_tid_t mtid, int flags,
77 hammer2_blockref_t *obref);
78 static hammer2_io_t *hammer2_chain_drop_data(hammer2_chain_t *chain);
79 static hammer2_chain_t *hammer2_combined_find(
80 hammer2_chain_t *parent,
81 hammer2_blockref_t *base, int count,
82 hammer2_key_t *key_nextp,
83 hammer2_key_t key_beg, hammer2_key_t key_end,
84 hammer2_blockref_t **bresp);
86 static struct krate krate_h2me = { .freq = 1 };
89 * Basic RBTree for chains (core->rbtree and core->dbtree). Chains cannot
90 * overlap in the RB trees. Deleted chains are moved from rbtree to either
93 * Chains in delete-duplicate sequences can always iterate through core_entry
94 * to locate the live version of the chain.
96 RB_GENERATE(hammer2_chain_tree, hammer2_chain, rbnode, hammer2_chain_cmp);
99 hammer2_chain_cmp(hammer2_chain_t *chain1, hammer2_chain_t *chain2)
101 hammer2_key_t c1_beg;
102 hammer2_key_t c1_end;
103 hammer2_key_t c2_beg;
104 hammer2_key_t c2_end;
107 * Compare chains. Overlaps are not supposed to happen and catch
108 * any software issues early we count overlaps as a match.
110 c1_beg = chain1->bref.key;
111 c1_end = c1_beg + ((hammer2_key_t)1 << chain1->bref.keybits) - 1;
112 c2_beg = chain2->bref.key;
113 c2_end = c2_beg + ((hammer2_key_t)1 << chain2->bref.keybits) - 1;
115 if (c1_end < c2_beg) /* fully to the left */
117 if (c1_beg > c2_end) /* fully to the right */
119 return(0); /* overlap (must not cross edge boundary) */
123 * Assert that a chain has no media data associated with it.
126 hammer2_chain_assert_no_data(hammer2_chain_t *chain)
128 KKASSERT(chain->dio == NULL);
129 if (chain->bref.type != HAMMER2_BREF_TYPE_VOLUME &&
130 chain->bref.type != HAMMER2_BREF_TYPE_FREEMAP &&
132 panic("hammer2_assert_no_data: chain %p still has data", chain);
137 * Make a chain visible to the flusher. The flusher operates using a top-down
138 * recursion based on the ONFLUSH flag. It locates MODIFIED and UPDATE chains,
139 * flushes them, and updates blocks back to the volume root.
141 * This routine sets the ONFLUSH flag upward from the triggering chain until
142 * it hits an inode root or the volume root. Inode chains serve as inflection
143 * points, requiring the flusher to bridge across trees. Inodes include
144 * regular inodes, PFS roots (pmp->iroot), and the media super root
148 hammer2_chain_setflush(hammer2_chain_t *chain)
150 hammer2_chain_t *parent;
152 if ((chain->flags & HAMMER2_CHAIN_ONFLUSH) == 0) {
153 hammer2_spin_sh(&chain->core.spin);
154 while ((chain->flags & HAMMER2_CHAIN_ONFLUSH) == 0) {
155 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONFLUSH);
156 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE)
158 if ((parent = chain->parent) == NULL)
160 hammer2_spin_sh(&parent->core.spin);
161 hammer2_spin_unsh(&chain->core.spin);
164 hammer2_spin_unsh(&chain->core.spin);
169 * Allocate a new disconnected chain element representing the specified
170 * bref. chain->refs is set to 1 and the passed bref is copied to
171 * chain->bref. chain->bytes is derived from the bref.
173 * chain->pmp inherits pmp unless the chain is an inode (other than the
176 * NOTE: Returns a referenced but unlocked (because there is no core) chain.
179 hammer2_chain_alloc(hammer2_dev_t *hmp, hammer2_pfs_t *pmp,
180 hammer2_blockref_t *bref)
182 hammer2_chain_t *chain;
186 * Special case - radix of 0 indicates a chain that does not
187 * need a data reference (context is completely embedded in the
190 if ((int)(bref->data_off & HAMMER2_OFF_MASK_RADIX))
191 bytes = 1U << (int)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
195 atomic_add_long(&hammer2_chain_allocs, 1);
198 * Construct the appropriate system structure.
201 case HAMMER2_BREF_TYPE_DIRENT:
202 case HAMMER2_BREF_TYPE_INODE:
203 case HAMMER2_BREF_TYPE_INDIRECT:
204 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
205 case HAMMER2_BREF_TYPE_DATA:
206 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
208 * Chain's are really only associated with the hmp but we
209 * maintain a pmp association for per-mount memory tracking
210 * purposes. The pmp can be NULL.
212 chain = kmalloc(sizeof(*chain), hmp->mchain, M_WAITOK | M_ZERO);
214 case HAMMER2_BREF_TYPE_VOLUME:
215 case HAMMER2_BREF_TYPE_FREEMAP:
217 * Only hammer2_chain_bulksnap() calls this function with these
220 chain = kmalloc(sizeof(*chain), hmp->mchain, M_WAITOK | M_ZERO);
224 panic("hammer2_chain_alloc: unrecognized blockref type: %d",
229 * Initialize the new chain structure. pmp must be set to NULL for
230 * chains belonging to the super-root topology of a device mount.
232 if (pmp == hmp->spmp)
239 chain->bytes = bytes;
241 chain->flags = HAMMER2_CHAIN_ALLOCATED;
242 lockinit(&chain->diolk, "chdio", 0, 0);
245 * Set the PFS boundary flag if this chain represents a PFS root.
247 if (bref->flags & HAMMER2_BREF_FLAG_PFSROOT)
248 atomic_set_int(&chain->flags, HAMMER2_CHAIN_PFSBOUNDARY);
249 hammer2_chain_core_init(chain);
255 * Initialize a chain's core structure. This structure used to be allocated
256 * but is now embedded.
258 * The core is not locked. No additional refs on the chain are made.
259 * (trans) must not be NULL if (core) is not NULL.
262 hammer2_chain_core_init(hammer2_chain_t *chain)
265 * Fresh core under nchain (no multi-homing of ochain's
268 RB_INIT(&chain->core.rbtree); /* live chains */
269 hammer2_mtx_init(&chain->lock, "h2chain");
273 * Add a reference to a chain element, preventing its destruction.
275 * (can be called with spinlock held)
278 hammer2_chain_ref(hammer2_chain_t *chain)
280 if (atomic_fetchadd_int(&chain->refs, 1) == 0) {
282 * Just flag that the chain was used and should be recycled
283 * on the LRU if it encounters it later.
285 if (chain->flags & HAMMER2_CHAIN_ONLRU)
286 atomic_set_int(&chain->flags, HAMMER2_CHAIN_LRUHINT);
290 * REMOVED - reduces contention, lru_list is more heuristical
293 * 0->non-zero transition must ensure that chain is removed
296 * NOTE: Already holding lru_spin here so we cannot call
297 * hammer2_chain_ref() to get it off lru_list, do
300 if (chain->flags & HAMMER2_CHAIN_ONLRU) {
301 hammer2_pfs_t *pmp = chain->pmp;
302 hammer2_spin_ex(&pmp->lru_spin);
303 if (chain->flags & HAMMER2_CHAIN_ONLRU) {
304 atomic_add_int(&pmp->lru_count, -1);
305 atomic_clear_int(&chain->flags,
306 HAMMER2_CHAIN_ONLRU);
307 TAILQ_REMOVE(&pmp->lru_list, chain, lru_node);
309 hammer2_spin_unex(&pmp->lru_spin);
316 * Ref a locked chain and force the data to be held across an unlock.
317 * Chain must be currently locked. The user of the chain who desires
318 * to release the hold must call hammer2_chain_lock_unhold() to relock
319 * and unhold the chain, then unlock normally, or may simply call
320 * hammer2_chain_drop_unhold() (which is safer against deadlocks).
323 hammer2_chain_ref_hold(hammer2_chain_t *chain)
325 atomic_add_int(&chain->lockcnt, 1);
326 hammer2_chain_ref(chain);
330 * Insert the chain in the core rbtree.
332 * Normal insertions are placed in the live rbtree. Insertion of a deleted
333 * chain is a special case used by the flush code that is placed on the
334 * unstaged deleted list to avoid confusing the live view.
336 #define HAMMER2_CHAIN_INSERT_SPIN 0x0001
337 #define HAMMER2_CHAIN_INSERT_LIVE 0x0002
338 #define HAMMER2_CHAIN_INSERT_RACE 0x0004
342 hammer2_chain_insert(hammer2_chain_t *parent, hammer2_chain_t *chain,
343 int flags, int generation)
345 hammer2_chain_t *xchain;
348 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
349 hammer2_spin_ex(&parent->core.spin);
352 * Interlocked by spinlock, check for race
354 if ((flags & HAMMER2_CHAIN_INSERT_RACE) &&
355 parent->core.generation != generation) {
356 error = HAMMER2_ERROR_EAGAIN;
363 xchain = RB_INSERT(hammer2_chain_tree, &parent->core.rbtree, chain);
364 KASSERT(xchain == NULL,
365 ("hammer2_chain_insert: collision %p %p (key=%016jx)",
366 chain, xchain, chain->bref.key));
367 atomic_set_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
368 chain->parent = parent;
369 ++parent->core.chain_count;
370 ++parent->core.generation; /* XXX incs for _get() too, XXX */
373 * We have to keep track of the effective live-view blockref count
374 * so the create code knows when to push an indirect block.
376 if (flags & HAMMER2_CHAIN_INSERT_LIVE)
377 atomic_add_int(&parent->core.live_count, 1);
379 if (flags & HAMMER2_CHAIN_INSERT_SPIN)
380 hammer2_spin_unex(&parent->core.spin);
385 * Drop the caller's reference to the chain. When the ref count drops to
386 * zero this function will try to disassociate the chain from its parent and
387 * deallocate it, then recursely drop the parent using the implied ref
388 * from the chain's chain->parent.
390 * Nobody should own chain's mutex on the 1->0 transition, unless this drop
391 * races an acquisition by another cpu. Therefore we can loop if we are
392 * unable to acquire the mutex, and refs is unlikely to be 1 unless we again
393 * race against another drop.
395 static hammer2_chain_t *hammer2_chain_lastdrop(hammer2_chain_t *chain,
397 static void hammer2_chain_lru_flush(hammer2_pfs_t *pmp);
400 hammer2_chain_drop(hammer2_chain_t *chain)
404 if (hammer2_debug & 0x200000)
407 KKASSERT(chain->refs > 0);
415 if (hammer2_mtx_ex_try(&chain->lock) == 0)
416 chain = hammer2_chain_lastdrop(chain, 0);
417 /* retry the same chain, or chain from lastdrop */
419 if (atomic_cmpset_int(&chain->refs, refs, refs - 1))
421 /* retry the same chain */
428 * Unhold a held and probably not-locked chain, ensure that the data is
429 * dropped on the 1->0 transition of lockcnt by obtaining an exclusive
430 * lock and then simply unlocking the chain.
433 hammer2_chain_drop_unhold(hammer2_chain_t *chain)
439 lockcnt = chain->lockcnt;
442 if (atomic_cmpset_int(&chain->lockcnt,
443 lockcnt, lockcnt - 1)) {
446 } else if (hammer2_mtx_ex_try(&chain->lock) == 0) {
447 hammer2_chain_unlock(chain);
451 * This situation can easily occur on SMP due to
452 * the gap inbetween the 1->0 transition and the
453 * final unlock. We cannot safely block on the
454 * mutex because lockcnt might go above 1.
456 * XXX Sleep for one tick if it takes too long.
459 if (iter > 1000 + hz) {
460 kprintf("hammer2: h2race1 %p\n", chain);
463 tsleep(&iter, 0, "h2race1", 1);
468 hammer2_chain_drop(chain);
472 * Handles the (potential) last drop of chain->refs from 1->0. Called with
473 * the mutex exclusively locked, refs == 1, and lockcnt 0. SMP races are
474 * possible against refs and lockcnt. We must dispose of the mutex on chain.
476 * This function returns an unlocked chain for recursive drop or NULL. It
477 * can return the same chain if it determines it has raced another ref.
481 * When two chains need to be recursively dropped we use the chain we
482 * would otherwise free to placehold the additional chain. It's a bit
483 * convoluted but we can't just recurse without potentially blowing out
486 * The chain cannot be freed if it has any children.
487 * The chain cannot be freed if flagged MODIFIED unless we can dispose of it.
488 * The chain cannot be freed if flagged UPDATE unless we can dispose of it.
489 * Any dedup registration can remain intact.
491 * The core spinlock is allowed to nest child-to-parent (not parent-to-child).
495 hammer2_chain_lastdrop(hammer2_chain_t *chain, int depth)
499 hammer2_chain_t *parent;
500 hammer2_chain_t *rdrop;
503 * We need chain's spinlock to interlock the sub-tree test.
504 * We already have chain's mutex, protecting chain->parent.
506 * Remember that chain->refs can be in flux.
508 hammer2_spin_ex(&chain->core.spin);
510 if (chain->parent != NULL) {
512 * If the chain has a parent the UPDATE bit prevents scrapping
513 * as the chain is needed to properly flush the parent. Try
514 * to complete the 1->0 transition and return NULL. Retry
515 * (return chain) if we are unable to complete the 1->0
516 * transition, else return NULL (nothing more to do).
518 * If the chain has a parent the MODIFIED bit prevents
521 * Chains with UPDATE/MODIFIED are *not* put on the LRU list!
523 if (chain->flags & (HAMMER2_CHAIN_UPDATE |
524 HAMMER2_CHAIN_MODIFIED)) {
525 if (atomic_cmpset_int(&chain->refs, 1, 0)) {
526 hammer2_spin_unex(&chain->core.spin);
527 hammer2_chain_assert_no_data(chain);
528 hammer2_mtx_unlock(&chain->lock);
531 hammer2_spin_unex(&chain->core.spin);
532 hammer2_mtx_unlock(&chain->lock);
536 /* spinlock still held */
537 } else if (chain->bref.type == HAMMER2_BREF_TYPE_VOLUME ||
538 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP) {
540 * Retain the static vchain and fchain. Clear bits that
541 * are not relevant. Do not clear the MODIFIED bit,
542 * and certainly do not put it on the delayed-flush queue.
544 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_UPDATE);
547 * The chain has no parent and can be flagged for destruction.
548 * Since it has no parent, UPDATE can also be cleared.
550 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DESTROY);
551 if (chain->flags & HAMMER2_CHAIN_UPDATE)
552 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_UPDATE);
555 * If the chain has children we must propagate the DESTROY
556 * flag downward and rip the disconnected topology apart.
557 * This is accomplished by calling hammer2_flush() on the
560 * Any dedup is already handled by the underlying DIO, so
561 * we do not have to specifically flush it here.
563 if (chain->core.chain_count) {
564 hammer2_spin_unex(&chain->core.spin);
565 hammer2_flush(chain, HAMMER2_FLUSH_TOP |
567 hammer2_mtx_unlock(&chain->lock);
569 return(chain); /* retry drop */
573 * Otherwise we can scrap the MODIFIED bit if it is set,
574 * and continue along the freeing path.
576 * Be sure to clean-out any dedup bits. Without a parent
577 * this chain will no longer be visible to the flush code.
578 * Easy check data_off to avoid the volume root.
580 if (chain->flags & HAMMER2_CHAIN_MODIFIED) {
581 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
582 atomic_add_long(&hammer2_count_modified_chains, -1);
584 hammer2_pfs_memory_wakeup(chain->pmp);
586 /* spinlock still held */
589 /* spinlock still held */
592 * If any children exist we must leave the chain intact with refs == 0.
593 * They exist because chains are retained below us which have refs or
594 * may require flushing.
596 * Retry (return chain) if we fail to transition the refs to 0, else
597 * return NULL indication nothing more to do.
599 * Chains with children are NOT put on the LRU list.
601 if (chain->core.chain_count) {
602 if (atomic_cmpset_int(&chain->refs, 1, 0)) {
603 hammer2_spin_unex(&chain->core.spin);
604 hammer2_chain_assert_no_data(chain);
605 hammer2_mtx_unlock(&chain->lock);
608 hammer2_spin_unex(&chain->core.spin);
609 hammer2_mtx_unlock(&chain->lock);
613 /* spinlock still held */
614 /* no chains left under us */
617 * chain->core has no children left so no accessors can get to our
618 * chain from there. Now we have to lock the parent core to interlock
619 * remaining possible accessors that might bump chain's refs before
620 * we can safely drop chain's refs with intent to free the chain.
623 pmp = chain->pmp; /* can be NULL */
626 parent = chain->parent;
629 * WARNING! chain's spin lock is still held here, and other spinlocks
630 * will be acquired and released in the code below. We
631 * cannot be making fancy procedure calls!
635 * We can cache the chain if it is associated with a pmp
636 * and not flagged as being destroyed or requesting a full
637 * release. In this situation the chain is not removed
638 * from its parent, i.e. it can still be looked up.
640 * We intentionally do not cache DATA chains because these
641 * were likely used to load data into the logical buffer cache
642 * and will not be accessed again for some time.
645 (HAMMER2_CHAIN_DESTROY | HAMMER2_CHAIN_RELEASE)) == 0 &&
647 chain->bref.type != HAMMER2_BREF_TYPE_DATA) {
649 hammer2_spin_ex(&parent->core.spin);
650 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) {
652 * 1->0 transition failed, retry. Do not drop
653 * the chain's data yet!
656 hammer2_spin_unex(&parent->core.spin);
657 hammer2_spin_unex(&chain->core.spin);
658 hammer2_mtx_unlock(&chain->lock);
666 hammer2_chain_assert_no_data(chain);
669 * Make sure we are on the LRU list, clean up excessive
670 * LRU entries. We can only really drop one but there might
671 * be other entries that we can remove from the lru_list
674 * NOTE: HAMMER2_CHAIN_ONLRU may only be safely set when
675 * chain->core.spin AND pmp->lru_spin are held, but
676 * can be safely cleared only holding pmp->lru_spin.
678 if ((chain->flags & HAMMER2_CHAIN_ONLRU) == 0) {
679 hammer2_spin_ex(&pmp->lru_spin);
680 if ((chain->flags & HAMMER2_CHAIN_ONLRU) == 0) {
681 atomic_set_int(&chain->flags,
682 HAMMER2_CHAIN_ONLRU);
683 TAILQ_INSERT_TAIL(&pmp->lru_list,
685 atomic_add_int(&pmp->lru_count, 1);
687 if (pmp->lru_count < HAMMER2_LRU_LIMIT)
688 depth = 1; /* disable lru_list flush */
689 hammer2_spin_unex(&pmp->lru_spin);
691 /* disable lru flush */
696 hammer2_spin_unex(&parent->core.spin);
697 parent = NULL; /* safety */
699 hammer2_spin_unex(&chain->core.spin);
700 hammer2_mtx_unlock(&chain->lock);
703 * lru_list hysteresis (see above for depth overrides).
704 * Note that depth also prevents excessive lastdrop recursion.
707 hammer2_chain_lru_flush(pmp);
714 * Make sure we are not on the LRU list.
716 if (chain->flags & HAMMER2_CHAIN_ONLRU) {
717 hammer2_spin_ex(&pmp->lru_spin);
718 if (chain->flags & HAMMER2_CHAIN_ONLRU) {
719 atomic_add_int(&pmp->lru_count, -1);
720 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONLRU);
721 TAILQ_REMOVE(&pmp->lru_list, chain, lru_node);
723 hammer2_spin_unex(&pmp->lru_spin);
727 * Spinlock the parent and try to drop the last ref on chain.
728 * On success determine if we should dispose of the chain
729 * (remove the chain from its parent, etc).
731 * (normal core locks are top-down recursive but we define
732 * core spinlocks as bottom-up recursive, so this is safe).
735 hammer2_spin_ex(&parent->core.spin);
736 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) {
738 * 1->0 transition failed, retry.
740 hammer2_spin_unex(&parent->core.spin);
741 hammer2_spin_unex(&chain->core.spin);
742 hammer2_mtx_unlock(&chain->lock);
748 * 1->0 transition successful, parent spin held to prevent
749 * new lookups, chain spinlock held to protect parent field.
750 * Remove chain from the parent.
752 * If the chain is being removed from the parent's btree but
753 * is not bmapped, we have to adjust live_count downward. If
754 * it is bmapped then the blockref is retained in the parent
755 * as is its associated live_count. This case can occur when
756 * a chain added to the topology is unable to flush and is
757 * then later deleted.
759 if (chain->flags & HAMMER2_CHAIN_ONRBTREE) {
760 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) &&
761 (chain->flags & HAMMER2_CHAIN_BMAPPED) == 0) {
762 atomic_add_int(&parent->core.live_count, -1);
764 RB_REMOVE(hammer2_chain_tree,
765 &parent->core.rbtree, chain);
766 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
767 --parent->core.chain_count;
768 chain->parent = NULL;
772 * If our chain was the last chain in the parent's core the
773 * core is now empty and its parent might have to be
774 * re-dropped if it has 0 refs.
776 if (parent->core.chain_count == 0) {
778 atomic_add_int(&rdrop->refs, 1);
780 if (atomic_cmpset_int(&rdrop->refs, 0, 1) == 0)
784 hammer2_spin_unex(&parent->core.spin);
785 parent = NULL; /* safety */
791 if (atomic_cmpset_int(&chain->refs, 1, 0) == 0) {
793 * 1->0 transition failed, retry.
795 hammer2_spin_unex(&parent->core.spin);
796 hammer2_spin_unex(&chain->core.spin);
797 hammer2_mtx_unlock(&chain->lock);
804 * Successful 1->0 transition, no parent, no children... no way for
805 * anyone to ref this chain any more. We can clean-up and free it.
807 * We still have the core spinlock, and core's chain_count is 0.
808 * Any parent spinlock is gone.
810 hammer2_spin_unex(&chain->core.spin);
811 hammer2_chain_assert_no_data(chain);
812 hammer2_mtx_unlock(&chain->lock);
813 KKASSERT(RB_EMPTY(&chain->core.rbtree) &&
814 chain->core.chain_count == 0);
817 * All locks are gone, no pointers remain to the chain, finish
820 KKASSERT((chain->flags & (HAMMER2_CHAIN_UPDATE |
821 HAMMER2_CHAIN_MODIFIED)) == 0);
824 * Once chain resources are gone we can use the now dead chain
825 * structure to placehold what might otherwise require a recursive
826 * drop, because we have potentially two things to drop and can only
827 * return one directly.
829 if (chain->flags & HAMMER2_CHAIN_ALLOCATED) {
830 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ALLOCATED);
832 kfree(chain, hmp->mchain);
836 * Possible chaining loop when parent re-drop needed.
842 * Heuristical flush of the LRU, try to reduce the number of entries
843 * on the LRU to (HAMMER2_LRU_LIMIT * 2 / 3). This procedure is called
844 * only when lru_count exceeds HAMMER2_LRU_LIMIT.
848 hammer2_chain_lru_flush(hammer2_pfs_t *pmp)
850 hammer2_chain_t *chain;
854 hammer2_spin_ex(&pmp->lru_spin);
855 while (pmp->lru_count > HAMMER2_LRU_LIMIT * 2 / 3) {
857 * Pick a chain off the lru_list, just recycle it quickly
858 * if LRUHINT is set (the chain was ref'd but left on
859 * the lru_list, so cycle to the end).
861 chain = TAILQ_FIRST(&pmp->lru_list);
862 TAILQ_REMOVE(&pmp->lru_list, chain, lru_node);
864 if (chain->flags & HAMMER2_CHAIN_LRUHINT) {
865 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_LRUHINT);
866 TAILQ_INSERT_TAIL(&pmp->lru_list, chain, lru_node);
872 * Ok, we are off the LRU. We must adjust refs before we
873 * can safely clear the ONLRU flag.
875 atomic_add_int(&pmp->lru_count, -1);
876 if (atomic_cmpset_int(&chain->refs, 0, 1)) {
877 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONLRU);
878 atomic_set_int(&chain->flags, HAMMER2_CHAIN_RELEASE);
881 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONLRU);
884 hammer2_spin_unex(&pmp->lru_spin);
889 * If we picked a chain off the lru list we may be able to lastdrop
890 * it. Use a depth of 1 to prevent excessive lastdrop recursion.
900 if (hammer2_mtx_ex_try(&chain->lock) == 0)
901 chain = hammer2_chain_lastdrop(chain, 1);
902 /* retry the same chain, or chain from lastdrop */
904 if (atomic_cmpset_int(&chain->refs, refs, refs - 1))
906 /* retry the same chain */
914 * On last lock release.
916 static hammer2_io_t *
917 hammer2_chain_drop_data(hammer2_chain_t *chain)
921 if ((dio = chain->dio) != NULL) {
925 switch(chain->bref.type) {
926 case HAMMER2_BREF_TYPE_VOLUME:
927 case HAMMER2_BREF_TYPE_FREEMAP:
930 if (chain->data != NULL) {
931 hammer2_spin_unex(&chain->core.spin);
932 panic("chain data not null: "
933 "chain %p bref %016jx.%02x "
934 "refs %d parent %p dio %p data %p",
935 chain, chain->bref.data_off,
936 chain->bref.type, chain->refs,
938 chain->dio, chain->data);
940 KKASSERT(chain->data == NULL);
948 * Lock a referenced chain element, acquiring its data with I/O if necessary,
949 * and specify how you would like the data to be resolved.
951 * If an I/O or other fatal error occurs, chain->error will be set to non-zero.
953 * The lock is allowed to recurse, multiple locking ops will aggregate
954 * the requested resolve types. Once data is assigned it will not be
955 * removed until the last unlock.
957 * HAMMER2_RESOLVE_NEVER - Do not resolve the data element.
958 * (typically used to avoid device/logical buffer
961 * HAMMER2_RESOLVE_MAYBE - Do not resolve data elements for chains in
962 * the INITIAL-create state (indirect blocks only).
964 * Do not resolve data elements for DATA chains.
965 * (typically used to avoid device/logical buffer
968 * HAMMER2_RESOLVE_ALWAYS- Always resolve the data element.
970 * HAMMER2_RESOLVE_SHARED- (flag) The chain is locked shared, otherwise
971 * it will be locked exclusive.
973 * HAMMER2_RESOLVE_NONBLOCK- (flag) The chain is locked non-blocking. If
974 * the lock fails, EAGAIN is returned.
976 * NOTE: Embedded elements (volume header, inodes) are always resolved
979 * NOTE: Specifying HAMMER2_RESOLVE_ALWAYS on a newly-created non-embedded
980 * element will instantiate and zero its buffer, and flush it on
983 * NOTE: (data) elements are normally locked RESOLVE_NEVER or RESOLVE_MAYBE
984 * so as not to instantiate a device buffer, which could alias against
985 * a logical file buffer. However, if ALWAYS is specified the
986 * device buffer will be instantiated anyway.
988 * NOTE: The return value is always 0 unless NONBLOCK is specified, in which
989 * case it can be either 0 or EAGAIN.
991 * WARNING! This function blocks on I/O if data needs to be fetched. This
992 * blocking can run concurrent with other compatible lock holders
993 * who do not need data returning. The lock is not upgraded to
994 * exclusive during a data fetch, a separate bit is used to
995 * interlock I/O. However, an exclusive lock holder can still count
996 * on being interlocked against an I/O fetch managed by a shared
1000 hammer2_chain_lock(hammer2_chain_t *chain, int how)
1002 KKASSERT(chain->refs > 0);
1004 if (how & HAMMER2_RESOLVE_NONBLOCK) {
1006 * We still have to bump lockcnt before acquiring the lock,
1007 * even for non-blocking operation, because the unlock code
1008 * live-loops on lockcnt == 1 when dropping the last lock.
1010 * If the non-blocking operation fails we have to use a
1011 * ref+drop+unhold sequence to undo the mess (or write a
1012 * hammer2_chain_unhold() function that doesn't drop).
1014 * NOTE: LOCKAGAIN must always succeed without blocking,
1015 * even if NONBLOCK is specified.
1017 atomic_add_int(&chain->lockcnt, 1);
1018 if (how & HAMMER2_RESOLVE_SHARED) {
1019 if (how & HAMMER2_RESOLVE_LOCKAGAIN) {
1020 hammer2_mtx_sh_again(&chain->lock);
1022 if (hammer2_mtx_sh_try(&chain->lock) != 0) {
1023 hammer2_chain_ref(chain);
1024 hammer2_chain_drop_unhold(chain);
1029 if (hammer2_mtx_ex_try(&chain->lock) != 0) {
1030 hammer2_chain_ref(chain);
1031 hammer2_chain_drop_unhold(chain);
1035 ++curthread->td_tracker;
1038 * Get the appropriate lock. If LOCKAGAIN is flagged with
1039 * SHARED the caller expects a shared lock to already be
1040 * present and we are giving it another ref. This case must
1041 * importantly not block if there is a pending exclusive lock
1044 atomic_add_int(&chain->lockcnt, 1);
1045 if (how & HAMMER2_RESOLVE_SHARED) {
1046 if (how & HAMMER2_RESOLVE_LOCKAGAIN) {
1047 hammer2_mtx_sh_again(&chain->lock);
1049 hammer2_mtx_sh(&chain->lock);
1052 hammer2_mtx_ex(&chain->lock);
1054 ++curthread->td_tracker;
1058 * If we already have a valid data pointer make sure the data is
1059 * synchronized to the current cpu, and then no further action is
1064 hammer2_io_bkvasync(chain->dio);
1069 * Do we have to resolve the data? This is generally only
1070 * applicable to HAMMER2_BREF_TYPE_DATA which is special-cased.
1071 * Other BREF types expects the data to be there.
1073 switch(how & HAMMER2_RESOLVE_MASK) {
1074 case HAMMER2_RESOLVE_NEVER:
1076 case HAMMER2_RESOLVE_MAYBE:
1077 if (chain->flags & HAMMER2_CHAIN_INITIAL)
1079 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA)
1082 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE)
1084 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF)
1088 case HAMMER2_RESOLVE_ALWAYS:
1094 * Caller requires data
1096 hammer2_chain_load_data(chain);
1102 * Lock the chain, retain the hold, and drop the data persistence count.
1103 * The data should remain valid because we never transitioned lockcnt
1107 hammer2_chain_lock_unhold(hammer2_chain_t *chain, int how)
1109 hammer2_chain_lock(chain, how);
1110 atomic_add_int(&chain->lockcnt, -1);
1115 * Downgrade an exclusive chain lock to a shared chain lock.
1117 * NOTE: There is no upgrade equivalent due to the ease of
1118 * deadlocks in that direction.
1121 hammer2_chain_lock_downgrade(hammer2_chain_t *chain)
1123 hammer2_mtx_downgrade(&chain->lock);
1128 * Issue I/O and install chain->data. Caller must hold a chain lock, lock
1129 * may be of any type.
1131 * Once chain->data is set it cannot be disposed of until all locks are
1134 * Make sure the data is synchronized to the current cpu.
1137 hammer2_chain_load_data(hammer2_chain_t *chain)
1139 hammer2_blockref_t *bref;
1146 * Degenerate case, data already present, or chain has no media
1147 * reference to load.
1149 KKASSERT(chain->lock.mtx_lock & MTX_MASK);
1152 hammer2_io_bkvasync(chain->dio);
1155 if ((chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX) == 0)
1159 KKASSERT(hmp != NULL);
1162 * Gain the IOINPROG bit, interlocked block.
1168 oflags = chain->flags;
1170 if (oflags & HAMMER2_CHAIN_IOINPROG) {
1171 nflags = oflags | HAMMER2_CHAIN_IOSIGNAL;
1172 tsleep_interlock(&chain->flags, 0);
1173 if (atomic_cmpset_int(&chain->flags, oflags, nflags)) {
1174 tsleep(&chain->flags, PINTERLOCKED,
1179 nflags = oflags | HAMMER2_CHAIN_IOINPROG;
1180 if (atomic_cmpset_int(&chain->flags, oflags, nflags)) {
1188 * We own CHAIN_IOINPROG
1190 * Degenerate case if we raced another load.
1194 hammer2_io_bkvasync(chain->dio);
1199 * We must resolve to a device buffer, either by issuing I/O or
1200 * by creating a zero-fill element. We do not mark the buffer
1201 * dirty when creating a zero-fill element (the hammer2_chain_modify()
1202 * API must still be used to do that).
1204 * The device buffer is variable-sized in powers of 2 down
1205 * to HAMMER2_MIN_ALLOC (typically 1K). A 64K physical storage
1206 * chunk always contains buffers of the same size. (XXX)
1208 * The minimum physical IO size may be larger than the variable
1211 bref = &chain->bref;
1214 * The getblk() optimization can only be used on newly created
1215 * elements if the physical block size matches the request.
1217 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
1218 error = hammer2_io_new(hmp, bref->type,
1219 bref->data_off, chain->bytes,
1222 error = hammer2_io_bread(hmp, bref->type,
1223 bref->data_off, chain->bytes,
1225 hammer2_adjreadcounter(&chain->bref, chain->bytes);
1228 chain->error = HAMMER2_ERROR_EIO;
1229 kprintf("hammer2_chain_lock: I/O error %016jx: %d\n",
1230 (intmax_t)bref->data_off, error);
1231 hammer2_io_bqrelse(&chain->dio);
1237 * This isn't perfect and can be ignored on OSs which do not have
1238 * an indication as to whether a buffer is coming from cache or
1239 * if I/O was actually issued for the read. TESTEDGOOD will work
1240 * pretty well without the B_IOISSUED logic because chains are
1241 * cached, but in that situation (without B_IOISSUED) it will not
1242 * detect whether a re-read via I/O is corrupted verses the original
1245 * We can't re-run the CRC on every fresh lock. That would be
1246 * insanely expensive.
1248 * If the underlying kernel buffer covers the entire chain we can
1249 * use the B_IOISSUED indication to determine if we have to re-run
1250 * the CRC on chain data for chains that managed to stay cached
1251 * across the kernel disposal of the original buffer.
1253 if ((dio = chain->dio) != NULL && dio->bp) {
1254 struct buf *bp = dio->bp;
1256 if (dio->psize == chain->bytes &&
1257 (bp->b_flags & B_IOISSUED)) {
1258 atomic_clear_int(&chain->flags,
1259 HAMMER2_CHAIN_TESTEDGOOD);
1260 bp->b_flags &= ~B_IOISSUED;
1265 * NOTE: A locked chain's data cannot be modified without first
1266 * calling hammer2_chain_modify().
1270 * Clear INITIAL. In this case we used io_new() and the buffer has
1271 * been zero'd and marked dirty.
1273 * NOTE: hammer2_io_data() call issues bkvasync()
1275 bdata = hammer2_io_data(chain->dio, chain->bref.data_off);
1277 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
1278 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1279 chain->bref.flags |= HAMMER2_BREF_FLAG_ZERO;
1280 } else if (chain->flags & HAMMER2_CHAIN_MODIFIED) {
1282 * check data not currently synchronized due to
1283 * modification. XXX assumes data stays in the buffer
1284 * cache, which might not be true (need biodep on flush
1285 * to calculate crc? or simple crc?).
1287 } else if ((chain->flags & HAMMER2_CHAIN_TESTEDGOOD) == 0) {
1288 if (hammer2_chain_testcheck(chain, bdata) == 0) {
1289 chain->error = HAMMER2_ERROR_CHECK;
1291 atomic_set_int(&chain->flags, HAMMER2_CHAIN_TESTEDGOOD);
1296 * Setup the data pointer, either pointing it to an embedded data
1297 * structure and copying the data from the buffer, or pointing it
1300 * The buffer is not retained when copying to an embedded data
1301 * structure in order to avoid potential deadlocks or recursions
1302 * on the same physical buffer.
1304 * WARNING! Other threads can start using the data the instant we
1305 * set chain->data non-NULL.
1307 switch (bref->type) {
1308 case HAMMER2_BREF_TYPE_VOLUME:
1309 case HAMMER2_BREF_TYPE_FREEMAP:
1311 * Copy data from bp to embedded buffer
1313 panic("hammer2_chain_load_data: unresolved volume header");
1315 case HAMMER2_BREF_TYPE_DIRENT:
1316 KKASSERT(chain->bytes != 0);
1318 case HAMMER2_BREF_TYPE_INODE:
1319 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1320 case HAMMER2_BREF_TYPE_INDIRECT:
1321 case HAMMER2_BREF_TYPE_DATA:
1322 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1325 * Point data at the device buffer and leave dio intact.
1327 chain->data = (void *)bdata;
1332 * Release HAMMER2_CHAIN_IOINPROG and signal waiters if requested.
1339 oflags = chain->flags;
1340 nflags = oflags & ~(HAMMER2_CHAIN_IOINPROG |
1341 HAMMER2_CHAIN_IOSIGNAL);
1342 KKASSERT(oflags & HAMMER2_CHAIN_IOINPROG);
1343 if (atomic_cmpset_int(&chain->flags, oflags, nflags)) {
1344 if (oflags & HAMMER2_CHAIN_IOSIGNAL)
1345 wakeup(&chain->flags);
1352 * Unlock and deref a chain element.
1354 * Remember that the presence of children under chain prevent the chain's
1355 * destruction but do not add additional references, so the dio will still
1359 hammer2_chain_unlock(hammer2_chain_t *chain)
1365 --curthread->td_tracker;
1368 * If multiple locks are present (or being attempted) on this
1369 * particular chain we can just unlock, drop refs, and return.
1371 * Otherwise fall-through on the 1->0 transition.
1374 lockcnt = chain->lockcnt;
1375 KKASSERT(lockcnt > 0);
1378 if (atomic_cmpset_int(&chain->lockcnt,
1379 lockcnt, lockcnt - 1)) {
1380 hammer2_mtx_unlock(&chain->lock);
1383 } else if (hammer2_mtx_upgrade_try(&chain->lock) == 0) {
1384 /* while holding the mutex exclusively */
1385 if (atomic_cmpset_int(&chain->lockcnt, 1, 0))
1389 * This situation can easily occur on SMP due to
1390 * the gap inbetween the 1->0 transition and the
1391 * final unlock. We cannot safely block on the
1392 * mutex because lockcnt might go above 1.
1394 * XXX Sleep for one tick if it takes too long.
1396 if (++iter > 1000) {
1397 if (iter > 1000 + hz) {
1398 kprintf("hammer2: h2race2 %p\n", chain);
1401 tsleep(&iter, 0, "h2race2", 1);
1409 * Last unlock / mutex upgraded to exclusive. Drop the data
1412 dio = hammer2_chain_drop_data(chain);
1414 hammer2_io_bqrelse(&dio);
1415 hammer2_mtx_unlock(&chain->lock);
1419 * Unlock and hold chain data intact
1422 hammer2_chain_unlock_hold(hammer2_chain_t *chain)
1424 atomic_add_int(&chain->lockcnt, 1);
1425 hammer2_chain_unlock(chain);
1429 * Helper to obtain the blockref[] array base and count for a chain.
1431 * XXX Not widely used yet, various use cases need to be validated and
1432 * converted to use this function.
1435 hammer2_blockref_t *
1436 hammer2_chain_base_and_count(hammer2_chain_t *parent, int *countp)
1438 hammer2_blockref_t *base;
1441 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
1444 switch(parent->bref.type) {
1445 case HAMMER2_BREF_TYPE_INODE:
1446 count = HAMMER2_SET_COUNT;
1448 case HAMMER2_BREF_TYPE_INDIRECT:
1449 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1450 count = parent->bytes / sizeof(hammer2_blockref_t);
1452 case HAMMER2_BREF_TYPE_VOLUME:
1453 count = HAMMER2_SET_COUNT;
1455 case HAMMER2_BREF_TYPE_FREEMAP:
1456 count = HAMMER2_SET_COUNT;
1459 panic("hammer2_chain_create_indirect: "
1460 "unrecognized blockref type: %d",
1466 switch(parent->bref.type) {
1467 case HAMMER2_BREF_TYPE_INODE:
1468 base = &parent->data->ipdata.u.blockset.blockref[0];
1469 count = HAMMER2_SET_COUNT;
1471 case HAMMER2_BREF_TYPE_INDIRECT:
1472 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1473 base = &parent->data->npdata[0];
1474 count = parent->bytes / sizeof(hammer2_blockref_t);
1476 case HAMMER2_BREF_TYPE_VOLUME:
1477 base = &parent->data->voldata.
1478 sroot_blockset.blockref[0];
1479 count = HAMMER2_SET_COUNT;
1481 case HAMMER2_BREF_TYPE_FREEMAP:
1482 base = &parent->data->blkset.blockref[0];
1483 count = HAMMER2_SET_COUNT;
1486 panic("hammer2_chain_create_indirect: "
1487 "unrecognized blockref type: %d",
1499 * This counts the number of live blockrefs in a block array and
1500 * also calculates the point at which all remaining blockrefs are empty.
1501 * This routine can only be called on a live chain.
1503 * Caller holds the chain locked, but possibly with a shared lock. We
1504 * must use an exclusive spinlock to prevent corruption.
1506 * NOTE: Flag is not set until after the count is complete, allowing
1507 * callers to test the flag without holding the spinlock.
1509 * NOTE: If base is NULL the related chain is still in the INITIAL
1510 * state and there are no blockrefs to count.
1512 * NOTE: live_count may already have some counts accumulated due to
1513 * creation and deletion and could even be initially negative.
1516 hammer2_chain_countbrefs(hammer2_chain_t *chain,
1517 hammer2_blockref_t *base, int count)
1519 hammer2_spin_ex(&chain->core.spin);
1520 if ((chain->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0) {
1522 while (--count >= 0) {
1523 if (base[count].type)
1526 chain->core.live_zero = count + 1;
1527 while (count >= 0) {
1528 if (base[count].type)
1529 atomic_add_int(&chain->core.live_count,
1534 chain->core.live_zero = 0;
1536 /* else do not modify live_count */
1537 atomic_set_int(&chain->flags, HAMMER2_CHAIN_COUNTEDBREFS);
1539 hammer2_spin_unex(&chain->core.spin);
1543 * Resize the chain's physical storage allocation in-place. This function does
1544 * not usually adjust the data pointer and must be followed by (typically) a
1545 * hammer2_chain_modify() call to copy any old data over and adjust the
1548 * Chains can be resized smaller without reallocating the storage. Resizing
1549 * larger will reallocate the storage. Excess or prior storage is reclaimed
1550 * asynchronously at a later time.
1552 * An nradix value of 0 is special-cased to mean that the storage should
1553 * be disassociated, that is the chain is being resized to 0 bytes (not 1
1556 * Must be passed an exclusively locked parent and chain.
1558 * This function is mostly used with DATA blocks locked RESOLVE_NEVER in order
1559 * to avoid instantiating a device buffer that conflicts with the vnode data
1560 * buffer. However, because H2 can compress or encrypt data, the chain may
1561 * have a dio assigned to it in those situations, and they do not conflict.
1563 * XXX return error if cannot resize.
1566 hammer2_chain_resize(hammer2_chain_t *chain,
1567 hammer2_tid_t mtid, hammer2_off_t dedup_off,
1568 int nradix, int flags)
1578 * Only data and indirect blocks can be resized for now.
1579 * (The volu root, inodes, and freemap elements use a fixed size).
1581 KKASSERT(chain != &hmp->vchain);
1582 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA ||
1583 chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
1584 chain->bref.type == HAMMER2_BREF_TYPE_DIRENT);
1587 * Nothing to do if the element is already the proper size
1589 obytes = chain->bytes;
1590 nbytes = (nradix) ? (1U << nradix) : 0;
1591 if (obytes == nbytes)
1592 return (chain->error);
1595 * Make sure the old data is instantiated so we can copy it. If this
1596 * is a data block, the device data may be superfluous since the data
1597 * might be in a logical block, but compressed or encrypted data is
1600 * NOTE: The modify will set BMAPUPD for us if BMAPPED is set.
1602 error = hammer2_chain_modify(chain, mtid, dedup_off, 0);
1607 * Relocate the block, even if making it smaller (because different
1608 * block sizes may be in different regions).
1610 * NOTE: Operation does not copy the data and may only be used
1611 * to resize data blocks in-place, or directory entry blocks
1612 * which are about to be modified in some manner.
1614 error = hammer2_freemap_alloc(chain, nbytes);
1618 chain->bytes = nbytes;
1621 * We don't want the followup chain_modify() to try to copy data
1622 * from the old (wrong-sized) buffer. It won't know how much to
1623 * copy. This case should only occur during writes when the
1624 * originator already has the data to write in-hand.
1627 KKASSERT(chain->bref.type == HAMMER2_BREF_TYPE_DATA ||
1628 chain->bref.type == HAMMER2_BREF_TYPE_DIRENT);
1629 hammer2_io_brelse(&chain->dio);
1632 return (chain->error);
1636 * Set the chain modified so its data can be changed by the caller, or
1637 * install deduplicated data. The caller must call this routine for each
1638 * set of modifications it makes, even if the chain is already flagged
1641 * Sets bref.modify_tid to mtid only if mtid != 0. Note that bref.modify_tid
1642 * is a CLC (cluster level change) field and is not updated by parent
1643 * propagation during a flush.
1645 * Returns an appropriate HAMMER2_ERROR_* code, which will generally reflect
1646 * chain->error except for HAMMER2_ERROR_ENOSPC. If the allocation fails
1647 * due to no space available, HAMMER2_ERROR_ENOSPC is returned and the chain
1648 * remains unmodified with its old data ref intact and chain->error
1653 * If the DEDUPABLE flag is set in the chain the storage must be reallocated
1654 * even if the chain is still flagged MODIFIED. In this case the chain's
1655 * DEDUPABLE flag will be cleared once the new storage has been assigned.
1657 * If the caller passes a non-zero dedup_off we will use it to assign the
1658 * new storage. The MODIFIED flag will be *CLEARED* in this case, and
1659 * DEDUPABLE will be set (NOTE: the UPDATE flag is always set). The caller
1660 * must not modify the data content upon return.
1663 hammer2_chain_modify(hammer2_chain_t *chain, hammer2_tid_t mtid,
1664 hammer2_off_t dedup_off, int flags)
1666 hammer2_blockref_t obref;
1677 obref = chain->bref;
1678 KKASSERT((chain->flags & HAMMER2_CHAIN_FICTITIOUS) == 0);
1679 KKASSERT(chain->lock.mtx_lock & MTX_EXCLUSIVE);
1682 * Data is not optional for freemap chains (we must always be sure
1683 * to copy the data on COW storage allocations).
1685 if (chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
1686 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
1687 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) ||
1688 (flags & HAMMER2_MODIFY_OPTDATA) == 0);
1692 * Data must be resolved if already assigned, unless explicitly
1693 * flagged otherwise. If we cannot safety load the data the
1694 * modification fails and we return early.
1696 if (chain->data == NULL && chain->bytes != 0 &&
1697 (flags & HAMMER2_MODIFY_OPTDATA) == 0 &&
1698 (chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX)) {
1699 hammer2_chain_load_data(chain);
1701 return (chain->error);
1706 * Set MODIFIED to indicate that the chain has been modified. A new
1707 * allocation is required when modifying a chain.
1709 * Set UPDATE to ensure that the blockref is updated in the parent.
1711 * If MODIFIED is already set determine if we can reuse the assigned
1712 * data block or if we need a new data block.
1714 if ((chain->flags & HAMMER2_CHAIN_MODIFIED) == 0) {
1716 * Must set modified bit.
1718 atomic_add_long(&hammer2_count_modified_chains, 1);
1719 atomic_set_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
1720 hammer2_pfs_memory_inc(chain->pmp); /* can be NULL */
1724 * We may be able to avoid a copy-on-write if the chain's
1725 * check mode is set to NONE and the chain's current
1726 * modify_tid is beyond the last explicit snapshot tid.
1728 * This implements HAMMER2's overwrite-in-place feature.
1730 * NOTE! This data-block cannot be used as a de-duplication
1731 * source when the check mode is set to NONE.
1733 if ((chain->bref.type == HAMMER2_BREF_TYPE_DATA ||
1734 chain->bref.type == HAMMER2_BREF_TYPE_DIRENT) &&
1735 (chain->flags & HAMMER2_CHAIN_INITIAL) == 0 &&
1736 (chain->flags & HAMMER2_CHAIN_DEDUPABLE) == 0 &&
1737 HAMMER2_DEC_CHECK(chain->bref.methods) ==
1738 HAMMER2_CHECK_NONE &&
1740 chain->bref.modify_tid >
1741 chain->pmp->iroot->meta.pfs_lsnap_tid) {
1743 * Sector overwrite allowed.
1748 * Sector overwrite not allowed, must copy-on-write.
1752 } else if (chain->flags & HAMMER2_CHAIN_DEDUPABLE) {
1754 * If the modified chain was registered for dedup we need
1755 * a new allocation. This only happens for delayed-flush
1756 * chains (i.e. which run through the front-end buffer
1763 * Already flagged modified, no new allocation is needed.
1770 * Flag parent update required.
1772 if ((chain->flags & HAMMER2_CHAIN_UPDATE) == 0) {
1773 atomic_set_int(&chain->flags, HAMMER2_CHAIN_UPDATE);
1780 * The XOP code returns held but unlocked focus chains. This
1781 * prevents the chain from being destroyed but does not prevent
1782 * it from being modified. diolk is used to interlock modifications
1783 * against XOP frontend accesses to the focus.
1785 * This allows us to theoretically avoid deadlocking the frontend
1786 * if one of the backends lock up by not formally locking the
1787 * focused chain in the frontend. In addition, the synchronization
1788 * code relies on this mechanism to avoid deadlocking concurrent
1789 * synchronization threads.
1791 lockmgr(&chain->diolk, LK_EXCLUSIVE);
1794 * The modification or re-modification requires an allocation and
1795 * possible COW. If an error occurs, the previous content and data
1796 * reference is retained and the modification fails.
1798 * If dedup_off is non-zero, the caller is requesting a deduplication
1799 * rather than a modification. The MODIFIED bit is not set and the
1800 * data offset is set to the deduplication offset. The data cannot
1803 * NOTE: The dedup offset is allowed to be in a partially free state
1804 * and we must be sure to reset it to a fully allocated state
1805 * to force two bulkfree passes to free it again.
1807 * NOTE: Only applicable when chain->bytes != 0.
1809 * XXX can a chain already be marked MODIFIED without a data
1810 * assignment? If not, assert here instead of testing the case.
1812 if (chain != &hmp->vchain && chain != &hmp->fchain &&
1814 if ((chain->bref.data_off & ~HAMMER2_OFF_MASK_RADIX) == 0 ||
1818 * NOTE: We do not have to remove the dedup
1819 * registration because the area is still
1820 * allocated and the underlying DIO will
1824 chain->bref.data_off = dedup_off;
1825 chain->bytes = 1 << (dedup_off &
1826 HAMMER2_OFF_MASK_RADIX);
1828 atomic_clear_int(&chain->flags,
1829 HAMMER2_CHAIN_MODIFIED);
1830 atomic_add_long(&hammer2_count_modified_chains,
1833 hammer2_pfs_memory_wakeup(chain->pmp);
1834 hammer2_freemap_adjust(hmp, &chain->bref,
1835 HAMMER2_FREEMAP_DORECOVER);
1836 atomic_set_int(&chain->flags,
1837 HAMMER2_CHAIN_DEDUPABLE);
1839 error = hammer2_freemap_alloc(chain,
1841 atomic_clear_int(&chain->flags,
1842 HAMMER2_CHAIN_DEDUPABLE);
1848 * Stop here if error. We have to undo any flag bits we might
1853 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_MODIFIED);
1854 atomic_add_long(&hammer2_count_modified_chains, -1);
1856 hammer2_pfs_memory_wakeup(chain->pmp);
1859 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_UPDATE);
1861 lockmgr(&chain->diolk, LK_RELEASE);
1867 * Update mirror_tid and modify_tid. modify_tid is only updated
1868 * if not passed as zero (during flushes, parent propagation passes
1871 * NOTE: chain->pmp could be the device spmp.
1873 chain->bref.mirror_tid = hmp->voldata.mirror_tid + 1;
1875 chain->bref.modify_tid = mtid;
1878 * Set BMAPUPD to tell the flush code that an existing blockmap entry
1879 * requires updating as well as to tell the delete code that the
1880 * chain's blockref might not exactly match (in terms of physical size
1881 * or block offset) the one in the parent's blocktable. The base key
1882 * of course will still match.
1884 if (chain->flags & HAMMER2_CHAIN_BMAPPED)
1885 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPUPD);
1888 * Short-cut data blocks which the caller does not need an actual
1889 * data reference to (aka OPTDATA), as long as the chain does not
1890 * already have a data pointer to the data. This generally means
1891 * that the modifications are being done via the logical buffer cache.
1892 * The INITIAL flag relates only to the device data buffer and thus
1893 * remains unchange in this situation.
1895 * This code also handles bytes == 0 (most dirents).
1897 if (chain->bref.type == HAMMER2_BREF_TYPE_DATA &&
1898 (flags & HAMMER2_MODIFY_OPTDATA) &&
1899 chain->data == NULL) {
1900 KKASSERT(chain->dio == NULL);
1905 * Clearing the INITIAL flag (for indirect blocks) indicates that
1906 * we've processed the uninitialized storage allocation.
1908 * If this flag is already clear we are likely in a copy-on-write
1909 * situation but we have to be sure NOT to bzero the storage if
1910 * no data is present.
1912 if (chain->flags & HAMMER2_CHAIN_INITIAL) {
1913 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
1920 * Instantiate data buffer and possibly execute COW operation
1922 switch(chain->bref.type) {
1923 case HAMMER2_BREF_TYPE_VOLUME:
1924 case HAMMER2_BREF_TYPE_FREEMAP:
1926 * The data is embedded, no copy-on-write operation is
1929 KKASSERT(chain->dio == NULL);
1931 case HAMMER2_BREF_TYPE_DIRENT:
1933 * The data might be fully embedded.
1935 if (chain->bytes == 0) {
1936 KKASSERT(chain->dio == NULL);
1940 case HAMMER2_BREF_TYPE_INODE:
1941 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
1942 case HAMMER2_BREF_TYPE_DATA:
1943 case HAMMER2_BREF_TYPE_INDIRECT:
1944 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
1946 * Perform the copy-on-write operation
1948 * zero-fill or copy-on-write depending on whether
1949 * chain->data exists or not and set the dirty state for
1950 * the new buffer. hammer2_io_new() will handle the
1953 * If a dedup_off was supplied this is an existing block
1954 * and no COW, copy, or further modification is required.
1956 KKASSERT(chain != &hmp->vchain && chain != &hmp->fchain);
1958 if (wasinitial && dedup_off == 0) {
1959 error = hammer2_io_new(hmp, chain->bref.type,
1960 chain->bref.data_off,
1961 chain->bytes, &dio);
1963 error = hammer2_io_bread(hmp, chain->bref.type,
1964 chain->bref.data_off,
1965 chain->bytes, &dio);
1967 hammer2_adjreadcounter(&chain->bref, chain->bytes);
1970 * If an I/O error occurs make sure callers cannot accidently
1971 * modify the old buffer's contents and corrupt the filesystem.
1973 * NOTE: hammer2_io_data() call issues bkvasync()
1976 kprintf("hammer2_chain_modify: hmp=%p I/O error\n",
1978 chain->error = HAMMER2_ERROR_EIO;
1979 hammer2_io_brelse(&dio);
1980 hammer2_io_brelse(&chain->dio);
1985 bdata = hammer2_io_data(dio, chain->bref.data_off);
1989 * COW (unless a dedup).
1991 KKASSERT(chain->dio != NULL);
1992 if (chain->data != (void *)bdata && dedup_off == 0) {
1993 bcopy(chain->data, bdata, chain->bytes);
1995 } else if (wasinitial == 0) {
1997 * We have a problem. We were asked to COW but
1998 * we don't have any data to COW with!
2000 panic("hammer2_chain_modify: having a COW %p\n",
2005 * Retire the old buffer, replace with the new. Dirty or
2006 * redirty the new buffer.
2008 * WARNING! The system buffer cache may have already flushed
2009 * the buffer, so we must be sure to [re]dirty it
2010 * for further modification.
2012 * If dedup_off was supplied, the caller is not
2013 * expected to make any further modification to the
2016 * WARNING! hammer2_get_gdata() assumes dio never transitions
2017 * through NULL in order to optimize away unnecessary
2023 if ((tio = chain->dio) != NULL)
2024 hammer2_io_bqrelse(&tio);
2025 chain->data = (void *)bdata;
2028 hammer2_io_setdirty(dio);
2032 panic("hammer2_chain_modify: illegal non-embedded type %d",
2039 * setflush on parent indicating that the parent must recurse down
2040 * to us. Do not call on chain itself which might already have it
2044 hammer2_chain_setflush(chain->parent);
2045 lockmgr(&chain->diolk, LK_RELEASE);
2047 return (chain->error);
2051 * Modify the chain associated with an inode.
2054 hammer2_chain_modify_ip(hammer2_inode_t *ip, hammer2_chain_t *chain,
2055 hammer2_tid_t mtid, int flags)
2059 hammer2_inode_modify(ip);
2060 error = hammer2_chain_modify(chain, mtid, 0, flags);
2066 * Volume header data locks
2069 hammer2_voldata_lock(hammer2_dev_t *hmp)
2071 lockmgr(&hmp->vollk, LK_EXCLUSIVE);
2075 hammer2_voldata_unlock(hammer2_dev_t *hmp)
2077 lockmgr(&hmp->vollk, LK_RELEASE);
2081 hammer2_voldata_modify(hammer2_dev_t *hmp)
2083 if ((hmp->vchain.flags & HAMMER2_CHAIN_MODIFIED) == 0) {
2084 atomic_add_long(&hammer2_count_modified_chains, 1);
2085 atomic_set_int(&hmp->vchain.flags, HAMMER2_CHAIN_MODIFIED);
2086 hammer2_pfs_memory_inc(hmp->vchain.pmp);
2091 * This function returns the chain at the nearest key within the specified
2092 * range. The returned chain will be referenced but not locked.
2094 * This function will recurse through chain->rbtree as necessary and will
2095 * return a *key_nextp suitable for iteration. *key_nextp is only set if
2096 * the iteration value is less than the current value of *key_nextp.
2098 * The caller should use (*key_nextp) to calculate the actual range of
2099 * the returned element, which will be (key_beg to *key_nextp - 1), because
2100 * there might be another element which is superior to the returned element
2103 * (*key_nextp) can be passed as key_beg in an iteration only while non-NULL
2104 * chains continue to be returned. On EOF (*key_nextp) may overflow since
2105 * it will wind up being (key_end + 1).
2107 * WARNING! Must be called with child's spinlock held. Spinlock remains
2108 * held through the operation.
2110 struct hammer2_chain_find_info {
2111 hammer2_chain_t *best;
2112 hammer2_key_t key_beg;
2113 hammer2_key_t key_end;
2114 hammer2_key_t key_next;
2117 static int hammer2_chain_find_cmp(hammer2_chain_t *child, void *data);
2118 static int hammer2_chain_find_callback(hammer2_chain_t *child, void *data);
2122 hammer2_chain_find(hammer2_chain_t *parent, hammer2_key_t *key_nextp,
2123 hammer2_key_t key_beg, hammer2_key_t key_end)
2125 struct hammer2_chain_find_info info;
2128 info.key_beg = key_beg;
2129 info.key_end = key_end;
2130 info.key_next = *key_nextp;
2132 RB_SCAN(hammer2_chain_tree, &parent->core.rbtree,
2133 hammer2_chain_find_cmp, hammer2_chain_find_callback,
2135 *key_nextp = info.key_next;
2137 kprintf("chain_find %p %016jx:%016jx next=%016jx\n",
2138 parent, key_beg, key_end, *key_nextp);
2146 hammer2_chain_find_cmp(hammer2_chain_t *child, void *data)
2148 struct hammer2_chain_find_info *info = data;
2149 hammer2_key_t child_beg;
2150 hammer2_key_t child_end;
2152 child_beg = child->bref.key;
2153 child_end = child_beg + ((hammer2_key_t)1 << child->bref.keybits) - 1;
2155 if (child_end < info->key_beg)
2157 if (child_beg > info->key_end)
2164 hammer2_chain_find_callback(hammer2_chain_t *child, void *data)
2166 struct hammer2_chain_find_info *info = data;
2167 hammer2_chain_t *best;
2168 hammer2_key_t child_end;
2171 * WARNING! Layerq is scanned forwards, exact matches should keep
2172 * the existing info->best.
2174 if ((best = info->best) == NULL) {
2176 * No previous best. Assign best
2179 } else if (best->bref.key <= info->key_beg &&
2180 child->bref.key <= info->key_beg) {
2185 /*info->best = child;*/
2186 } else if (child->bref.key < best->bref.key) {
2188 * Child has a nearer key and best is not flush with key_beg.
2189 * Set best to child. Truncate key_next to the old best key.
2192 if (info->key_next > best->bref.key || info->key_next == 0)
2193 info->key_next = best->bref.key;
2194 } else if (child->bref.key == best->bref.key) {
2196 * If our current best is flush with the child then this
2197 * is an illegal overlap.
2199 * key_next will automatically be limited to the smaller of
2200 * the two end-points.
2206 * Keep the current best but truncate key_next to the child's
2209 * key_next will also automatically be limited to the smaller
2210 * of the two end-points (probably not necessary for this case
2211 * but we do it anyway).
2213 if (info->key_next > child->bref.key || info->key_next == 0)
2214 info->key_next = child->bref.key;
2218 * Always truncate key_next based on child's end-of-range.
2220 child_end = child->bref.key + ((hammer2_key_t)1 << child->bref.keybits);
2221 if (child_end && (info->key_next > child_end || info->key_next == 0))
2222 info->key_next = child_end;
2228 * Retrieve the specified chain from a media blockref, creating the
2229 * in-memory chain structure which reflects it. The returned chain is
2230 * held and locked according to (how) (HAMMER2_RESOLVE_*). The caller must
2231 * handle crc-checks and so forth, and should check chain->error before
2232 * assuming that the data is good.
2234 * To handle insertion races pass the INSERT_RACE flag along with the
2235 * generation number of the core. NULL will be returned if the generation
2236 * number changes before we have a chance to insert the chain. Insert
2237 * races can occur because the parent might be held shared.
2239 * Caller must hold the parent locked shared or exclusive since we may
2240 * need the parent's bref array to find our block.
2242 * WARNING! chain->pmp is always set to NULL for any chain representing
2243 * part of the super-root topology.
2246 hammer2_chain_get(hammer2_chain_t *parent, int generation,
2247 hammer2_blockref_t *bref, int how)
2249 hammer2_dev_t *hmp = parent->hmp;
2250 hammer2_chain_t *chain;
2254 * Allocate a chain structure representing the existing media
2255 * entry. Resulting chain has one ref and is not locked.
2257 if (bref->flags & HAMMER2_BREF_FLAG_PFSROOT)
2258 chain = hammer2_chain_alloc(hmp, NULL, bref);
2260 chain = hammer2_chain_alloc(hmp, parent->pmp, bref);
2261 /* ref'd chain returned */
2264 * Flag that the chain is in the parent's blockmap so delete/flush
2265 * knows what to do with it.
2267 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPPED);
2270 * chain must be locked to avoid unexpected ripouts
2272 hammer2_chain_lock(chain, how);
2275 * Link the chain into its parent. A spinlock is required to safely
2276 * access the RBTREE, and it is possible to collide with another
2277 * hammer2_chain_get() operation because the caller might only hold
2278 * a shared lock on the parent.
2280 * NOTE: Get races can occur quite often when we distribute
2281 * asynchronous read-aheads across multiple threads.
2283 KKASSERT(parent->refs > 0);
2284 error = hammer2_chain_insert(parent, chain,
2285 HAMMER2_CHAIN_INSERT_SPIN |
2286 HAMMER2_CHAIN_INSERT_RACE,
2289 KKASSERT((chain->flags & HAMMER2_CHAIN_ONRBTREE) == 0);
2290 /*kprintf("chain %p get race\n", chain);*/
2291 hammer2_chain_unlock(chain);
2292 hammer2_chain_drop(chain);
2295 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
2299 * Return our new chain referenced but not locked, or NULL if
2306 * Lookup initialization/completion API
2309 hammer2_chain_lookup_init(hammer2_chain_t *parent, int flags)
2311 hammer2_chain_ref(parent);
2312 if (flags & HAMMER2_LOOKUP_SHARED) {
2313 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS |
2314 HAMMER2_RESOLVE_SHARED);
2316 hammer2_chain_lock(parent, HAMMER2_RESOLVE_ALWAYS);
2322 hammer2_chain_lookup_done(hammer2_chain_t *parent)
2325 hammer2_chain_unlock(parent);
2326 hammer2_chain_drop(parent);
2331 * Take the locked chain and return a locked parent. The chain remains
2332 * locked on return, but may have to be temporarily unlocked to acquire
2333 * the parent. Because of this, (chain) must be stable and cannot be
2334 * deleted while it was temporarily unlocked (typically means that (chain)
2337 * Pass HAMMER2_RESOLVE_* flags in flags.
2339 * This will work even if the chain is errored, and the caller can check
2340 * parent->error on return if desired since the parent will be locked.
2342 * This function handles the lock order reversal.
2345 hammer2_chain_getparent(hammer2_chain_t *chain, int flags)
2347 hammer2_chain_t *parent;
2350 * Be careful of order, chain must be unlocked before parent
2351 * is locked below to avoid a deadlock. Try it trivially first.
2353 parent = chain->parent;
2355 panic("hammer2_chain_getparent: no parent");
2356 hammer2_chain_ref(parent);
2357 if (hammer2_chain_lock(parent, flags|HAMMER2_RESOLVE_NONBLOCK) == 0)
2361 hammer2_chain_unlock(chain);
2362 hammer2_chain_lock(parent, flags);
2363 hammer2_chain_lock(chain, flags);
2366 * Parent relinking races are quite common. We have to get
2367 * it right or we will blow up the block table.
2369 if (chain->parent == parent)
2371 hammer2_chain_unlock(parent);
2372 hammer2_chain_drop(parent);
2374 parent = chain->parent;
2376 panic("hammer2_chain_getparent: no parent");
2377 hammer2_chain_ref(parent);
2383 * Take the locked chain and return a locked parent. The chain is unlocked
2384 * and dropped. *chainp is set to the returned parent as a convenience.
2385 * Pass HAMMER2_RESOLVE_* flags in flags.
2387 * This will work even if the chain is errored, and the caller can check
2388 * parent->error on return if desired since the parent will be locked.
2390 * The chain does NOT need to be stable. We use a tracking structure
2391 * to track the expected parent if the chain is deleted out from under us.
2393 * This function handles the lock order reversal.
2396 hammer2_chain_repparent(hammer2_chain_t **chainp, int flags)
2398 hammer2_chain_t *chain;
2399 hammer2_chain_t *parent;
2400 struct hammer2_reptrack reptrack;
2401 struct hammer2_reptrack **repp;
2404 * Be careful of order, chain must be unlocked before parent
2405 * is locked below to avoid a deadlock. Try it trivially first.
2408 parent = chain->parent;
2409 if (parent == NULL) {
2410 hammer2_spin_unex(&chain->core.spin);
2411 panic("hammer2_chain_repparent: no parent");
2413 hammer2_chain_ref(parent);
2414 if (hammer2_chain_lock(parent, flags|HAMMER2_RESOLVE_NONBLOCK) == 0) {
2415 hammer2_chain_unlock(chain);
2416 hammer2_chain_drop(chain);
2423 * Ok, now it gets a bit nasty. There are multiple situations where
2424 * the parent might be in the middle of a deletion, or where the child
2425 * (chain) might be deleted the instant we let go of its lock.
2426 * We can potentially end up in a no-win situation!
2428 * In particular, the indirect_maintenance() case can cause these
2431 * To deal with this we install a reptrack structure in the parent
2432 * This reptrack structure 'owns' the parent ref and will automatically
2433 * migrate to the parent's parent if the parent is deleted permanently.
2435 hammer2_spin_init(&reptrack.spin, "h2reptrk");
2436 reptrack.chain = parent;
2437 hammer2_chain_ref(parent); /* for the reptrack */
2439 hammer2_spin_ex(&parent->core.spin);
2440 reptrack.next = parent->core.reptrack;
2441 parent->core.reptrack = &reptrack;
2442 hammer2_spin_unex(&parent->core.spin);
2444 hammer2_chain_unlock(chain);
2445 hammer2_chain_drop(chain);
2446 chain = NULL; /* gone */
2449 * At the top of this loop, chain is gone and parent is refd both
2450 * by us explicitly AND via our reptrack. We are attempting to
2454 hammer2_chain_lock(parent, flags);
2456 if (reptrack.chain == parent)
2458 hammer2_chain_unlock(parent);
2459 hammer2_chain_drop(parent);
2461 kprintf("hammer2: debug REPTRACK %p->%p\n",
2462 parent, reptrack.chain);
2463 hammer2_spin_ex(&reptrack.spin);
2464 parent = reptrack.chain;
2465 hammer2_chain_ref(parent);
2466 hammer2_spin_unex(&reptrack.spin);
2470 * Once parent is locked and matches our reptrack, our reptrack
2471 * will be stable and we have our parent. We can unlink our
2474 * WARNING! Remember that the chain lock might be shared. Chains
2475 * locked shared have stable parent linkages.
2477 hammer2_spin_ex(&parent->core.spin);
2478 repp = &parent->core.reptrack;
2479 while (*repp != &reptrack)
2480 repp = &(*repp)->next;
2481 *repp = reptrack.next;
2482 hammer2_spin_unex(&parent->core.spin);
2484 hammer2_chain_drop(parent); /* reptrack ref */
2485 *chainp = parent; /* return parent lock+ref */
2491 * Dispose of any linked reptrack structures in (chain) by shifting them to
2492 * (parent). Both (chain) and (parent) must be exclusively locked.
2494 * This is interlocked against any children of (chain) on the other side.
2495 * No children so remain as-of when this is called so we can test
2496 * core.reptrack without holding the spin-lock.
2498 * Used whenever the caller intends to permanently delete chains related
2499 * to topological recursions (BREF_TYPE_INDIRECT, BREF_TYPE_FREEMAP_NODE),
2500 * where the chains underneath the node being deleted are given a new parent
2501 * above the node being deleted.
2505 hammer2_chain_repchange(hammer2_chain_t *parent, hammer2_chain_t *chain)
2507 struct hammer2_reptrack *reptrack;
2509 KKASSERT(chain->core.live_count == 0 && RB_EMPTY(&chain->core.rbtree));
2510 while (chain->core.reptrack) {
2511 hammer2_spin_ex(&parent->core.spin);
2512 hammer2_spin_ex(&chain->core.spin);
2513 reptrack = chain->core.reptrack;
2514 if (reptrack == NULL) {
2515 hammer2_spin_unex(&chain->core.spin);
2516 hammer2_spin_unex(&parent->core.spin);
2519 hammer2_spin_ex(&reptrack->spin);
2520 chain->core.reptrack = reptrack->next;
2521 reptrack->chain = parent;
2522 reptrack->next = parent->core.reptrack;
2523 parent->core.reptrack = reptrack;
2524 hammer2_chain_ref(parent); /* reptrack */
2526 hammer2_spin_unex(&chain->core.spin);
2527 hammer2_spin_unex(&parent->core.spin);
2528 kprintf("hammer2: debug repchange %p %p->%p\n",
2529 reptrack, chain, parent);
2530 hammer2_chain_drop(chain); /* reptrack */
2535 * Locate the first chain whos key range overlaps (key_beg, key_end) inclusive.
2536 * (*parentp) typically points to an inode but can also point to a related
2537 * indirect block and this function will recurse upwards and find the inode
2538 * or the nearest undeleted indirect block covering the key range.
2540 * This function unconditionally sets *errorp, replacing any previous value.
2542 * (*parentp) must be exclusive or shared locked (depending on flags) and
2543 * referenced and can be an inode or an existing indirect block within the
2546 * If (*parent) is errored out, this function will not attempt to recurse
2547 * the radix tree and will return NULL along with an appropriate *errorp.
2548 * If NULL is returned and *errorp is 0, the requested lookup could not be
2551 * On return (*parentp) will be modified to point at the deepest parent chain
2552 * element encountered during the search, as a helper for an insertion or
2555 * The new (*parentp) will be locked shared or exclusive (depending on flags),
2556 * and referenced, and the old will be unlocked and dereferenced (no change
2557 * if they are both the same). This is particularly important if the caller
2558 * wishes to insert a new chain, (*parentp) will be set properly even if NULL
2559 * is returned, as long as no error occurred.
2561 * The matching chain will be returned locked according to flags.
2565 * NULL is returned if no match was found, but (*parentp) will still
2566 * potentially be adjusted.
2568 * On return (*key_nextp) will point to an iterative value for key_beg.
2569 * (If NULL is returned (*key_nextp) is set to (key_end + 1)).
2571 * This function will also recurse up the chain if the key is not within the
2572 * current parent's range. (*parentp) can never be set to NULL. An iteration
2573 * can simply allow (*parentp) to float inside the loop.
2575 * NOTE! chain->data is not always resolved. By default it will not be
2576 * resolved for BREF_TYPE_DATA, FREEMAP_NODE, or FREEMAP_LEAF. Use
2577 * HAMMER2_LOOKUP_ALWAYS to force resolution (but be careful w/
2578 * BREF_TYPE_DATA as the device buffer can alias the logical file
2583 hammer2_chain_lookup(hammer2_chain_t **parentp, hammer2_key_t *key_nextp,
2584 hammer2_key_t key_beg, hammer2_key_t key_end,
2585 int *errorp, int flags)
2588 hammer2_chain_t *parent;
2589 hammer2_chain_t *chain;
2590 hammer2_blockref_t *base;
2591 hammer2_blockref_t *bref;
2592 hammer2_blockref_t bcopy;
2593 hammer2_key_t scan_beg;
2594 hammer2_key_t scan_end;
2596 int how_always = HAMMER2_RESOLVE_ALWAYS;
2597 int how_maybe = HAMMER2_RESOLVE_MAYBE;
2600 int maxloops = 300000;
2601 volatile hammer2_mtx_t save_mtx;
2603 if (flags & HAMMER2_LOOKUP_ALWAYS) {
2604 how_maybe = how_always;
2605 how = HAMMER2_RESOLVE_ALWAYS;
2606 } else if (flags & HAMMER2_LOOKUP_NODATA) {
2607 how = HAMMER2_RESOLVE_NEVER;
2609 how = HAMMER2_RESOLVE_MAYBE;
2611 if (flags & HAMMER2_LOOKUP_SHARED) {
2612 how_maybe |= HAMMER2_RESOLVE_SHARED;
2613 how_always |= HAMMER2_RESOLVE_SHARED;
2614 how |= HAMMER2_RESOLVE_SHARED;
2618 * Recurse (*parentp) upward if necessary until the parent completely
2619 * encloses the key range or we hit the inode.
2621 * Handle races against the flusher deleting indirect nodes on its
2622 * way back up by continuing to recurse upward past the deletion.
2628 while (parent->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
2629 parent->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2630 scan_beg = parent->bref.key;
2631 scan_end = scan_beg +
2632 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
2633 if ((parent->flags & HAMMER2_CHAIN_DELETED) == 0) {
2634 if (key_beg >= scan_beg && key_end <= scan_end)
2637 parent = hammer2_chain_repparent(parentp, how_maybe);
2640 if (--maxloops == 0)
2641 panic("hammer2_chain_lookup: maxloops");
2643 * Locate the blockref array. Currently we do a fully associative
2644 * search through the array.
2646 switch(parent->bref.type) {
2647 case HAMMER2_BREF_TYPE_INODE:
2649 * Special shortcut for embedded data returns the inode
2650 * itself. Callers must detect this condition and access
2651 * the embedded data (the strategy code does this for us).
2653 * This is only applicable to regular files and softlinks.
2655 * We need a second lock on parent. Since we already have
2656 * a lock we must pass LOCKAGAIN to prevent unexpected
2657 * blocking (we don't want to block on a second shared
2658 * ref if an exclusive lock is pending)
2660 if (parent->data->ipdata.meta.op_flags &
2661 HAMMER2_OPFLAG_DIRECTDATA) {
2662 if (flags & HAMMER2_LOOKUP_NODIRECT) {
2664 *key_nextp = key_end + 1;
2667 hammer2_chain_ref(parent);
2668 hammer2_chain_lock(parent, how_always |
2669 HAMMER2_RESOLVE_LOCKAGAIN);
2670 *key_nextp = key_end + 1;
2673 base = &parent->data->ipdata.u.blockset.blockref[0];
2674 count = HAMMER2_SET_COUNT;
2676 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
2677 case HAMMER2_BREF_TYPE_INDIRECT:
2679 * Handle MATCHIND on the parent
2681 if (flags & HAMMER2_LOOKUP_MATCHIND) {
2682 scan_beg = parent->bref.key;
2683 scan_end = scan_beg +
2684 ((hammer2_key_t)1 << parent->bref.keybits) - 1;
2685 if (key_beg == scan_beg && key_end == scan_end) {
2687 hammer2_chain_ref(chain);
2688 hammer2_chain_lock(chain, how_maybe);
2689 *key_nextp = scan_end + 1;
2695 * Optimize indirect blocks in the INITIAL state to avoid
2698 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
2701 if (parent->data == NULL) {
2702 kprintf("parent->data is NULL %p\n", parent);
2704 tsleep(parent, 0, "xxx", 0);
2706 base = &parent->data->npdata[0];
2708 count = parent->bytes / sizeof(hammer2_blockref_t);
2710 case HAMMER2_BREF_TYPE_VOLUME:
2711 base = &parent->data->voldata.sroot_blockset.blockref[0];
2712 count = HAMMER2_SET_COUNT;
2714 case HAMMER2_BREF_TYPE_FREEMAP:
2715 base = &parent->data->blkset.blockref[0];
2716 count = HAMMER2_SET_COUNT;
2719 kprintf("hammer2_chain_lookup: unrecognized "
2720 "blockref(B) type: %d",
2723 tsleep(&base, 0, "dead", 0);
2724 panic("hammer2_chain_lookup: unrecognized "
2725 "blockref(B) type: %d",
2727 base = NULL; /* safety */
2728 count = 0; /* safety */
2732 * No lookup is possible if the parent is errored. We delayed
2733 * this check as long as we could to ensure that the parent backup,
2734 * embedded data, and MATCHIND code could still execute.
2736 if (parent->error) {
2737 *errorp = parent->error;
2742 * Merged scan to find next candidate.
2744 * hammer2_base_*() functions require the parent->core.live_* fields
2745 * to be synchronized.
2747 * We need to hold the spinlock to access the block array and RB tree
2748 * and to interlock chain creation.
2750 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0)
2751 hammer2_chain_countbrefs(parent, base, count);
2756 hammer2_spin_ex(&parent->core.spin);
2757 chain = hammer2_combined_find(parent, base, count,
2761 generation = parent->core.generation;
2764 * Exhausted parent chain, iterate.
2767 KKASSERT(chain == NULL);
2768 hammer2_spin_unex(&parent->core.spin);
2769 if (key_beg == key_end) /* short cut single-key case */
2773 * Stop if we reached the end of the iteration.
2775 if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT &&
2776 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2781 * Calculate next key, stop if we reached the end of the
2782 * iteration, otherwise go up one level and loop.
2784 key_beg = parent->bref.key +
2785 ((hammer2_key_t)1 << parent->bref.keybits);
2786 if (key_beg == 0 || key_beg > key_end)
2788 parent = hammer2_chain_repparent(parentp, how_maybe);
2793 * Selected from blockref or in-memory chain.
2796 if (chain == NULL) {
2797 hammer2_spin_unex(&parent->core.spin);
2798 if (bcopy.type == HAMMER2_BREF_TYPE_INDIRECT ||
2799 bcopy.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2800 chain = hammer2_chain_get(parent, generation,
2803 chain = hammer2_chain_get(parent, generation,
2809 hammer2_chain_ref(chain);
2810 hammer2_spin_unex(&parent->core.spin);
2813 * chain is referenced but not locked. We must lock the
2814 * chain to obtain definitive state.
2816 if (bcopy.type == HAMMER2_BREF_TYPE_INDIRECT ||
2817 bcopy.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2818 hammer2_chain_lock(chain, how_maybe);
2820 hammer2_chain_lock(chain, how);
2822 KKASSERT(chain->parent == parent);
2824 if (bcmp(&bcopy, &chain->bref, sizeof(bcopy)) ||
2825 chain->parent != parent) {
2826 hammer2_chain_unlock(chain);
2827 hammer2_chain_drop(chain);
2828 chain = NULL; /* SAFETY */
2834 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX)
2836 * NOTE: Chain's key range is not relevant as there might be
2837 * one-offs within the range that are not deleted.
2839 * NOTE: Lookups can race delete-duplicate because
2840 * delete-duplicate does not lock the parent's core
2841 * (they just use the spinlock on the core).
2843 if (chain->flags & HAMMER2_CHAIN_DELETED) {
2844 kprintf("skip deleted chain %016jx.%02x key=%016jx\n",
2845 chain->bref.data_off, chain->bref.type,
2847 hammer2_chain_unlock(chain);
2848 hammer2_chain_drop(chain);
2849 chain = NULL; /* SAFETY */
2850 key_beg = *key_nextp;
2851 if (key_beg == 0 || key_beg > key_end)
2857 * If the chain element is an indirect block it becomes the new
2858 * parent and we loop on it. We must maintain our top-down locks
2859 * to prevent the flusher from interfering (i.e. doing a
2860 * delete-duplicate and leaving us recursing down a deleted chain).
2862 * The parent always has to be locked with at least RESOLVE_MAYBE
2863 * so we can access its data. It might need a fixup if the caller
2864 * passed incompatible flags. Be careful not to cause a deadlock
2865 * as a data-load requires an exclusive lock.
2867 * If HAMMER2_LOOKUP_MATCHIND is set and the indirect block's key
2868 * range is within the requested key range we return the indirect
2869 * block and do NOT loop. This is usually only used to acquire
2872 if (chain->bref.type == HAMMER2_BREF_TYPE_INDIRECT ||
2873 chain->bref.type == HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2874 save_mtx = parent->lock;
2875 hammer2_chain_unlock(parent);
2876 hammer2_chain_drop(parent);
2877 *parentp = parent = chain;
2878 chain = NULL; /* SAFETY */
2883 * All done, return the locked chain.
2885 * If the caller does not want a locked chain, replace the lock with
2886 * a ref. Perhaps this can eventually be optimized to not obtain the
2887 * lock in the first place for situations where the data does not
2888 * need to be resolved.
2890 * NOTE! A chain->error must be tested by the caller upon return.
2891 * *errorp is only set based on issues which occur while
2892 * trying to reach the chain.
2898 * After having issued a lookup we can iterate all matching keys.
2900 * If chain is non-NULL we continue the iteration from just after it's index.
2902 * If chain is NULL we assume the parent was exhausted and continue the
2903 * iteration at the next parent.
2905 * If a fatal error occurs (typically an I/O error), a dummy chain is
2906 * returned with chain->error and error-identifying information set. This
2907 * chain will assert if you try to do anything fancy with it.
2909 * XXX Depending on where the error occurs we should allow continued iteration.
2911 * parent must be locked on entry and remains locked throughout. chain's
2912 * lock status must match flags. Chain is always at least referenced.
2914 * WARNING! The MATCHIND flag does not apply to this function.
2917 hammer2_chain_next(hammer2_chain_t **parentp, hammer2_chain_t *chain,
2918 hammer2_key_t *key_nextp,
2919 hammer2_key_t key_beg, hammer2_key_t key_end,
2920 int *errorp, int flags)
2922 hammer2_chain_t *parent;
2926 * Calculate locking flags for upward recursion.
2928 how_maybe = HAMMER2_RESOLVE_MAYBE;
2929 if (flags & HAMMER2_LOOKUP_SHARED)
2930 how_maybe |= HAMMER2_RESOLVE_SHARED;
2936 * Calculate the next index and recalculate the parent if necessary.
2939 key_beg = chain->bref.key +
2940 ((hammer2_key_t)1 << chain->bref.keybits);
2941 hammer2_chain_unlock(chain);
2942 hammer2_chain_drop(chain);
2945 * chain invalid past this point, but we can still do a
2946 * pointer comparison w/parent.
2948 * Any scan where the lookup returned degenerate data embedded
2949 * in the inode has an invalid index and must terminate.
2951 if (chain == parent)
2953 if (key_beg == 0 || key_beg > key_end)
2956 } else if (parent->bref.type != HAMMER2_BREF_TYPE_INDIRECT &&
2957 parent->bref.type != HAMMER2_BREF_TYPE_FREEMAP_NODE) {
2959 * We reached the end of the iteration.
2964 * Continue iteration with next parent unless the current
2965 * parent covers the range.
2967 * (This also handles the case of a deleted, empty indirect
2970 key_beg = parent->bref.key +
2971 ((hammer2_key_t)1 << parent->bref.keybits);
2972 if (key_beg == 0 || key_beg > key_end)
2974 parent = hammer2_chain_repparent(parentp, how_maybe);
2980 return (hammer2_chain_lookup(parentp, key_nextp,
2986 * Caller wishes to iterate chains under parent, loading new chains into
2987 * chainp. Caller must initialize *chainp to NULL and *firstp to 1, and
2988 * then call hammer2_chain_scan() repeatedly until a non-zero return.
2989 * During the scan, *firstp will be set to 0 and (*chainp) will be replaced
2990 * with the returned chain for the scan. The returned *chainp will be
2991 * locked and referenced. Any prior contents will be unlocked and dropped.
2993 * Caller should check the return value. A normal scan EOF will return
2994 * exactly HAMMER2_ERROR_EOF. Any other non-zero value indicates an
2995 * error trying to access parent data. Any error in the returned chain
2996 * must be tested separately by the caller.
2998 * (*chainp) is dropped on each scan, but will only be set if the returned
2999 * element itself can recurse. Leaf elements are NOT resolved, loaded, or
3000 * returned via *chainp. The caller will get their bref only.
3002 * The raw scan function is similar to lookup/next but does not seek to a key.
3003 * Blockrefs are iterated via first_bref = (parent, NULL) and
3004 * next_chain = (parent, bref).
3006 * The passed-in parent must be locked and its data resolved. The function
3007 * nominally returns a locked and referenced *chainp != NULL for chains
3008 * the caller might need to recurse on (and will dipose of any *chainp passed
3009 * in). The caller must check the chain->bref.type either way.
3012 hammer2_chain_scan(hammer2_chain_t *parent, hammer2_chain_t **chainp,
3013 hammer2_blockref_t *bref, int *firstp,
3017 hammer2_blockref_t *base;
3018 hammer2_blockref_t *bref_ptr;
3020 hammer2_key_t next_key;
3021 hammer2_chain_t *chain = NULL;
3023 int how_always = HAMMER2_RESOLVE_ALWAYS;
3024 int how_maybe = HAMMER2_RESOLVE_MAYBE;
3027 int maxloops = 300000;
3034 * Scan flags borrowed from lookup.
3036 if (flags & HAMMER2_LOOKUP_ALWAYS) {
3037 how_maybe = how_always;
3038 how = HAMMER2_RESOLVE_ALWAYS;
3039 } else if (flags & HAMMER2_LOOKUP_NODATA) {
3040 how = HAMMER2_RESOLVE_NEVER;
3042 how = HAMMER2_RESOLVE_MAYBE;
3044 if (flags & HAMMER2_LOOKUP_SHARED) {
3045 how_maybe |= HAMMER2_RESOLVE_SHARED;
3046 how_always |= HAMMER2_RESOLVE_SHARED;
3047 how |= HAMMER2_RESOLVE_SHARED;
3051 * Calculate key to locate first/next element, unlocking the previous
3052 * element as we go. Be careful, the key calculation can overflow.
3054 * (also reset bref to NULL)
3060 key = bref->key + ((hammer2_key_t)1 << bref->keybits);
3061 if ((chain = *chainp) != NULL) {
3063 hammer2_chain_unlock(chain);
3064 hammer2_chain_drop(chain);
3068 error |= HAMMER2_ERROR_EOF;
3074 if (parent->error) {
3075 error = parent->error;
3078 if (--maxloops == 0)
3079 panic("hammer2_chain_scan: maxloops");
3082 * Locate the blockref array. Currently we do a fully associative
3083 * search through the array.
3085 switch(parent->bref.type) {
3086 case HAMMER2_BREF_TYPE_INODE:
3088 * An inode with embedded data has no sub-chains.
3090 * WARNING! Bulk scan code may pass a static chain marked
3091 * as BREF_TYPE_INODE with a copy of the volume
3092 * root blockset to snapshot the volume.
3094 if (parent->data->ipdata.meta.op_flags &
3095 HAMMER2_OPFLAG_DIRECTDATA) {
3096 error |= HAMMER2_ERROR_EOF;
3099 base = &parent->data->ipdata.u.blockset.blockref[0];
3100 count = HAMMER2_SET_COUNT;
3102 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3103 case HAMMER2_BREF_TYPE_INDIRECT:
3105 * Optimize indirect blocks in the INITIAL state to avoid
3108 if (parent->flags & HAMMER2_CHAIN_INITIAL) {
3111 if (parent->data == NULL)
3112 panic("parent->data is NULL");
3113 base = &parent->data->npdata[0];
3115 count = parent->bytes / sizeof(hammer2_blockref_t);
3117 case HAMMER2_BREF_TYPE_VOLUME:
3118 base = &parent->data->voldata.sroot_blockset.blockref[0];
3119 count = HAMMER2_SET_COUNT;
3121 case HAMMER2_BREF_TYPE_FREEMAP:
3122 base = &parent->data->blkset.blockref[0];
3123 count = HAMMER2_SET_COUNT;
3126 panic("hammer2_chain_lookup: unrecognized blockref type: %d",
3128 base = NULL; /* safety */
3129 count = 0; /* safety */
3133 * Merged scan to find next candidate.
3135 * hammer2_base_*() functions require the parent->core.live_* fields
3136 * to be synchronized.
3138 * We need to hold the spinlock to access the block array and RB tree
3139 * and to interlock chain creation.
3141 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0)
3142 hammer2_chain_countbrefs(parent, base, count);
3146 hammer2_spin_ex(&parent->core.spin);
3147 chain = hammer2_combined_find(parent, base, count,
3149 key, HAMMER2_KEY_MAX,
3151 generation = parent->core.generation;
3154 * Exhausted parent chain, we're done.
3156 if (bref_ptr == NULL) {
3157 hammer2_spin_unex(&parent->core.spin);
3158 KKASSERT(chain == NULL);
3159 error |= HAMMER2_ERROR_EOF;
3164 * Copy into the supplied stack-based blockref.
3169 * Selected from blockref or in-memory chain.
3171 if (chain == NULL) {
3172 switch(bref->type) {
3173 case HAMMER2_BREF_TYPE_INODE:
3174 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3175 case HAMMER2_BREF_TYPE_INDIRECT:
3176 case HAMMER2_BREF_TYPE_VOLUME:
3177 case HAMMER2_BREF_TYPE_FREEMAP:
3179 * Recursion, always get the chain
3181 hammer2_spin_unex(&parent->core.spin);
3182 chain = hammer2_chain_get(parent, generation,
3189 * No recursion, do not waste time instantiating
3190 * a chain, just iterate using the bref.
3192 hammer2_spin_unex(&parent->core.spin);
3197 * Recursion or not we need the chain in order to supply
3200 hammer2_chain_ref(chain);
3201 hammer2_spin_unex(&parent->core.spin);
3202 hammer2_chain_lock(chain, how);
3205 (bcmp(bref, &chain->bref, sizeof(*bref)) ||
3206 chain->parent != parent)) {
3207 hammer2_chain_unlock(chain);
3208 hammer2_chain_drop(chain);
3214 * Skip deleted chains (XXX cache 'i' end-of-block-array? XXX)
3216 * NOTE: chain's key range is not relevant as there might be
3217 * one-offs within the range that are not deleted.
3219 * NOTE: XXX this could create problems with scans used in
3220 * situations other than mount-time recovery.
3222 * NOTE: Lookups can race delete-duplicate because
3223 * delete-duplicate does not lock the parent's core
3224 * (they just use the spinlock on the core).
3226 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
3227 hammer2_chain_unlock(chain);
3228 hammer2_chain_drop(chain);
3233 error |= HAMMER2_ERROR_EOF;
3241 * All done, return the bref or NULL, supply chain if necessary.
3249 * Create and return a new hammer2 system memory structure of the specified
3250 * key, type and size and insert it under (*parentp). This is a full
3251 * insertion, based on the supplied key/keybits, and may involve creating
3252 * indirect blocks and moving other chains around via delete/duplicate.
3254 * This call can be made with parent == NULL as long as a non -1 methods
3255 * is supplied. hmp must also be supplied in this situation (otherwise
3256 * hmp is extracted from the supplied parent). The chain will be detached
3257 * from the topology. A later call with both parent and chain can be made
3260 * THE CALLER MUST HAVE ALREADY PROPERLY SEEKED (*parentp) TO THE INSERTION
3261 * POINT SANS ANY REQUIRED INDIRECT BLOCK CREATIONS DUE TO THE ARRAY BEING
3262 * FULL. This typically means that the caller is creating the chain after
3263 * doing a hammer2_chain_lookup().
3265 * (*parentp) must be exclusive locked and may be replaced on return
3266 * depending on how much work the function had to do.
3268 * (*parentp) must not be errored or this function will assert.
3270 * (*chainp) usually starts out NULL and returns the newly created chain,
3271 * but if the caller desires the caller may allocate a disconnected chain
3272 * and pass it in instead.
3274 * This function should NOT be used to insert INDIRECT blocks. It is
3275 * typically used to create/insert inodes and data blocks.
3277 * Caller must pass-in an exclusively locked parent the new chain is to
3278 * be inserted under, and optionally pass-in a disconnected, exclusively
3279 * locked chain to insert (else we create a new chain). The function will
3280 * adjust (*parentp) as necessary, create or connect the chain, and
3281 * return an exclusively locked chain in *chainp.
3283 * When creating a PFSROOT inode under the super-root, pmp is typically NULL
3284 * and will be reassigned.
3286 * NOTE: returns HAMMER_ERROR_* flags
3289 hammer2_chain_create(hammer2_chain_t **parentp, hammer2_chain_t **chainp,
3290 hammer2_dev_t *hmp, hammer2_pfs_t *pmp, int methods,
3291 hammer2_key_t key, int keybits, int type, size_t bytes,
3292 hammer2_tid_t mtid, hammer2_off_t dedup_off, int flags)
3294 hammer2_chain_t *chain;
3295 hammer2_chain_t *parent;
3296 hammer2_blockref_t *base;
3297 hammer2_blockref_t dummy;
3301 int maxloops = 300000;
3304 * Topology may be crossing a PFS boundary.
3308 KKASSERT(hammer2_mtx_owned(&parent->lock));
3309 KKASSERT(parent->error == 0);
3314 if (chain == NULL) {
3316 * First allocate media space and construct the dummy bref,
3317 * then allocate the in-memory chain structure. Set the
3318 * INITIAL flag for fresh chains which do not have embedded
3321 * XXX for now set the check mode of the child based on
3322 * the parent or, if the parent is an inode, the
3323 * specification in the inode.
3325 bzero(&dummy, sizeof(dummy));
3328 dummy.keybits = keybits;
3329 dummy.data_off = hammer2_getradix(bytes);
3332 * Inherit methods from parent by default. Primarily used
3333 * for BREF_TYPE_DATA. Non-data types *must* be set to
3334 * a non-NONE check algorithm.
3337 dummy.methods = parent->bref.methods;
3339 dummy.methods = (uint8_t)methods;
3341 if (type != HAMMER2_BREF_TYPE_DATA &&
3342 HAMMER2_DEC_CHECK(dummy.methods) == HAMMER2_CHECK_NONE) {
3344 HAMMER2_ENC_CHECK(HAMMER2_CHECK_DEFAULT);
3347 chain = hammer2_chain_alloc(hmp, pmp, &dummy);
3350 * Lock the chain manually, chain_lock will load the chain
3351 * which we do NOT want to do. (note: chain->refs is set
3352 * to 1 by chain_alloc() for us, but lockcnt is not).
3355 hammer2_mtx_ex(&chain->lock);
3357 ++curthread->td_tracker;
3360 * Set INITIAL to optimize I/O. The flag will generally be
3361 * processed when we call hammer2_chain_modify().
3363 * Recalculate bytes to reflect the actual media block
3364 * allocation. Handle special case radix 0 == 0 bytes.
3366 bytes = (size_t)(chain->bref.data_off & HAMMER2_OFF_MASK_RADIX);
3368 bytes = (hammer2_off_t)1 << bytes;
3369 chain->bytes = bytes;
3372 case HAMMER2_BREF_TYPE_VOLUME:
3373 case HAMMER2_BREF_TYPE_FREEMAP:
3374 panic("hammer2_chain_create: called with volume type");
3376 case HAMMER2_BREF_TYPE_INDIRECT:
3377 panic("hammer2_chain_create: cannot be used to"
3378 "create indirect block");
3380 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3381 panic("hammer2_chain_create: cannot be used to"
3382 "create freemap root or node");
3384 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
3385 KKASSERT(bytes == sizeof(chain->data->bmdata));
3387 case HAMMER2_BREF_TYPE_DIRENT:
3388 case HAMMER2_BREF_TYPE_INODE:
3389 case HAMMER2_BREF_TYPE_DATA:
3392 * leave chain->data NULL, set INITIAL
3394 KKASSERT(chain->data == NULL);
3395 atomic_set_int(&chain->flags, HAMMER2_CHAIN_INITIAL);
3400 * We are reattaching a previously deleted chain, possibly
3401 * under a new parent and possibly with a new key/keybits.
3402 * The chain does not have to be in a modified state. The
3403 * UPDATE flag will be set later on in this routine.
3405 * Do NOT mess with the current state of the INITIAL flag.
3407 chain->bref.key = key;
3408 chain->bref.keybits = keybits;
3409 if (chain->flags & HAMMER2_CHAIN_DELETED)
3410 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3411 KKASSERT(chain->parent == NULL);
3415 * Set the appropriate bref flag if requested.
3417 * NOTE! Callers can call this function to move chains without
3418 * knowing about special flags, so don't clear bref flags
3421 if (flags & HAMMER2_INSERT_PFSROOT)
3422 chain->bref.flags |= HAMMER2_BREF_FLAG_PFSROOT;
3428 * Calculate how many entries we have in the blockref array and
3429 * determine if an indirect block is required when inserting into
3433 if (--maxloops == 0)
3434 panic("hammer2_chain_create: maxloops");
3436 switch(parent->bref.type) {
3437 case HAMMER2_BREF_TYPE_INODE:
3438 if ((parent->data->ipdata.meta.op_flags &
3439 HAMMER2_OPFLAG_DIRECTDATA) != 0) {
3440 kprintf("hammer2: parent set for direct-data! "
3441 "pkey=%016jx ckey=%016jx\n",
3445 KKASSERT((parent->data->ipdata.meta.op_flags &
3446 HAMMER2_OPFLAG_DIRECTDATA) == 0);
3447 KKASSERT(parent->data != NULL);
3448 base = &parent->data->ipdata.u.blockset.blockref[0];
3449 count = HAMMER2_SET_COUNT;
3451 case HAMMER2_BREF_TYPE_INDIRECT:
3452 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3453 if (parent->flags & HAMMER2_CHAIN_INITIAL)
3456 base = &parent->data->npdata[0];
3457 count = parent->bytes / sizeof(hammer2_blockref_t);
3459 case HAMMER2_BREF_TYPE_VOLUME:
3460 KKASSERT(parent->data != NULL);
3461 base = &parent->data->voldata.sroot_blockset.blockref[0];
3462 count = HAMMER2_SET_COUNT;
3464 case HAMMER2_BREF_TYPE_FREEMAP:
3465 KKASSERT(parent->data != NULL);
3466 base = &parent->data->blkset.blockref[0];
3467 count = HAMMER2_SET_COUNT;
3470 panic("hammer2_chain_create: unrecognized blockref type: %d",
3478 * Make sure we've counted the brefs
3480 if ((parent->flags & HAMMER2_CHAIN_COUNTEDBREFS) == 0)
3481 hammer2_chain_countbrefs(parent, base, count);
3483 KASSERT(parent->core.live_count >= 0 &&
3484 parent->core.live_count <= count,
3485 ("bad live_count %d/%d (%02x, %d)",
3486 parent->core.live_count, count,
3487 parent->bref.type, parent->bytes));
3490 * If no free blockref could be found we must create an indirect
3491 * block and move a number of blockrefs into it. With the parent
3492 * locked we can safely lock each child in order to delete+duplicate
3493 * it without causing a deadlock.
3495 * This may return the new indirect block or the old parent depending
3496 * on where the key falls. NULL is returned on error.
3498 if (parent->core.live_count == count) {
3499 hammer2_chain_t *nparent;
3501 KKASSERT((flags & HAMMER2_INSERT_SAMEPARENT) == 0);
3503 nparent = hammer2_chain_create_indirect(parent, key, keybits,
3504 mtid, type, &error);
3505 if (nparent == NULL) {
3507 hammer2_chain_drop(chain);
3511 if (parent != nparent) {
3512 hammer2_chain_unlock(parent);
3513 hammer2_chain_drop(parent);
3514 parent = *parentp = nparent;
3520 * fall through if parent, or skip to here if no parent.
3523 if (chain->flags & HAMMER2_CHAIN_DELETED)
3524 kprintf("Inserting deleted chain @%016jx\n",
3528 * Link the chain into its parent.
3530 if (chain->parent != NULL)
3531 panic("hammer2: hammer2_chain_create: chain already connected");
3532 KKASSERT(chain->parent == NULL);
3534 KKASSERT(parent->core.live_count < count);
3535 hammer2_chain_insert(parent, chain,
3536 HAMMER2_CHAIN_INSERT_SPIN |
3537 HAMMER2_CHAIN_INSERT_LIVE,
3543 * Mark the newly created chain modified. This will cause
3544 * UPDATE to be set and process the INITIAL flag.
3546 * Device buffers are not instantiated for DATA elements
3547 * as these are handled by logical buffers.
3549 * Indirect and freemap node indirect blocks are handled
3550 * by hammer2_chain_create_indirect() and not by this
3553 * Data for all other bref types is expected to be
3554 * instantiated (INODE, LEAF).
3556 switch(chain->bref.type) {
3557 case HAMMER2_BREF_TYPE_DATA:
3558 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
3559 case HAMMER2_BREF_TYPE_DIRENT:
3560 case HAMMER2_BREF_TYPE_INODE:
3561 error = hammer2_chain_modify(chain, mtid, dedup_off,
3562 HAMMER2_MODIFY_OPTDATA);
3566 * Remaining types are not supported by this function.
3567 * In particular, INDIRECT and LEAF_NODE types are
3568 * handled by create_indirect().
3570 panic("hammer2_chain_create: bad type: %d",
3577 * When reconnecting a chain we must set UPDATE and
3578 * setflush so the flush recognizes that it must update
3579 * the bref in the parent.
3581 if ((chain->flags & HAMMER2_CHAIN_UPDATE) == 0)
3582 atomic_set_int(&chain->flags, HAMMER2_CHAIN_UPDATE);
3586 * We must setflush(parent) to ensure that it recurses through to
3587 * chain. setflush(chain) might not work because ONFLUSH is possibly
3588 * already set in the chain (so it won't recurse up to set it in the
3592 hammer2_chain_setflush(parent);
3601 * Move the chain from its old parent to a new parent. The chain must have
3602 * already been deleted or already disconnected (or never associated) with
3603 * a parent. The chain is reassociated with the new parent and the deleted
3604 * flag will be cleared (no longer deleted). The chain's modification state
3607 * THE CALLER MUST HAVE ALREADY PROPERLY SEEKED (parent) TO THE INSERTION
3608 * POINT SANS ANY REQUIRED INDIRECT BLOCK CREATIONS DUE TO THE ARRAY BEING
3609 * FULL. This typically means that the caller is creating the chain after
3610 * doing a hammer2_chain_lookup().
3612 * Neither (parent) or (chain) can be errored.
3614 * If (parent) is non-NULL then the chain is inserted under the parent.
3616 * If (parent) is NULL then the newly duplicated chain is not inserted
3617 * anywhere, similar to if it had just been chain_alloc()'d (suitable for
3618 * passing into hammer2_chain_create() after this function returns).
3620 * WARNING! This function calls create which means it can insert indirect
3621 * blocks. This can cause other unrelated chains in the parent to
3622 * be moved to a newly inserted indirect block in addition to the
3626 hammer2_chain_rename(hammer2_chain_t **parentp, hammer2_chain_t *chain,
3627 hammer2_tid_t mtid, int flags)
3629 hammer2_blockref_t *bref;
3631 hammer2_chain_t *parent;
3635 * WARNING! We should never resolve DATA to device buffers
3636 * (XXX allow it if the caller did?), and since
3637 * we currently do not have the logical buffer cache
3638 * buffer in-hand to fix its cached physical offset
3639 * we also force the modify code to not COW it. XXX
3641 * NOTE! We allow error'd chains to be renamed. The bref itself
3642 * is good and can be renamed. The content, however, may
3646 KKASSERT(chain->parent == NULL);
3647 /*KKASSERT(chain->error == 0); allow */
3650 * Now create a duplicate of the chain structure, associating
3651 * it with the same core, making it the same size, pointing it
3652 * to the same bref (the same media block).
3654 * NOTE: Handle special radix == 0 case (means 0 bytes).
3656 bref = &chain->bref;
3657 bytes = (size_t)(bref->data_off & HAMMER2_OFF_MASK_RADIX);
3659 bytes = (hammer2_off_t)1 << bytes;
3662 * If parent is not NULL the duplicated chain will be entered under
3663 * the parent and the UPDATE bit set to tell flush to update
3666 * We must setflush(parent) to ensure that it recurses through to
3667 * chain. setflush(chain) might not work because ONFLUSH is possibly
3668 * already set in the chain (so it won't recurse up to set it in the
3671 * Having both chains locked is extremely important for atomicy.
3673 if (parentp && (parent = *parentp) != NULL) {
3674 KKASSERT(hammer2_mtx_owned(&parent->lock));
3675 KKASSERT(parent->refs > 0);
3676 KKASSERT(parent->error == 0);
3678 hammer2_chain_create(parentp, &chain, NULL, chain->pmp,
3679 HAMMER2_METH_DEFAULT,
3680 bref->key, bref->keybits, bref->type,
3681 chain->bytes, mtid, 0, flags);
3682 KKASSERT(chain->flags & HAMMER2_CHAIN_UPDATE);
3683 hammer2_chain_setflush(*parentp);
3688 * This works in tandem with delete_obref() to install a blockref in
3689 * (typically) an indirect block that is associated with the chain being
3690 * moved to *parentp.
3692 * The reason we need this function is that the caller needs to maintain
3693 * the blockref as it was, and not generate a new blockref for what might
3694 * be a modified chain. Otherwise stuff will leak into the flush that
3695 * the flush code's FLUSH_INODE_STOP flag is unable to catch.
3697 * It is EXTREMELY important that we properly set CHAIN_BMAPUPD and
3698 * CHAIN_UPDATE. We must set BMAPUPD if the bref does not match, and
3699 * we must clear CHAIN_UPDATE (that was likely set by the chain_rename) if
3700 * it does. Otherwise we can end up in a situation where H2 is unable to
3701 * clean up the in-memory chain topology.
3703 * The reason for this is that flushes do not generally flush through
3704 * BREF_TYPE_INODE chains and depend on a hammer2_inode_t queued to syncq
3705 * or sideq to properly flush and dispose of the related inode chain's flags.
3706 * Situations where the inode is not actually modified by the frontend,
3707 * but where we have to move the related chains around as we insert or cleanup
3708 * indirect blocks, can leave us with a 'dirty' (non-disposable) in-memory
3709 * inode chain that does not have a hammer2_inode_t associated with it.
3712 hammer2_chain_rename_obref(hammer2_chain_t **parentp, hammer2_chain_t *chain,
3713 hammer2_tid_t mtid, int flags,
3714 hammer2_blockref_t *obref)
3716 hammer2_chain_rename(parentp, chain, mtid, flags);
3719 hammer2_blockref_t *tbase;
3722 KKASSERT((chain->flags & HAMMER2_CHAIN_BMAPPED) == 0);
3723 hammer2_chain_modify(*parentp, mtid, 0, 0);
3724 tbase = hammer2_chain_base_and_count(*parentp, &tcount);
3725 hammer2_base_insert(*parentp, tbase, tcount, chain, obref);
3726 if (bcmp(obref, &chain->bref, sizeof(chain->bref))) {
3727 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPUPD |
3728 HAMMER2_CHAIN_UPDATE);
3730 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_UPDATE);
3736 * Helper function for deleting chains.
3738 * The chain is removed from the live view (the RBTREE) as well as the parent's
3739 * blockmap. Both chain and its parent must be locked.
3741 * parent may not be errored. chain can be errored.
3744 _hammer2_chain_delete_helper(hammer2_chain_t *parent, hammer2_chain_t *chain,
3745 hammer2_tid_t mtid, int flags,
3746 hammer2_blockref_t *obref)
3751 KKASSERT((chain->flags & (HAMMER2_CHAIN_DELETED |
3752 HAMMER2_CHAIN_FICTITIOUS)) == 0);
3753 KKASSERT(chain->parent == parent);
3756 if (chain->flags & HAMMER2_CHAIN_BMAPPED) {
3758 * Chain is blockmapped, so there must be a parent.
3759 * Atomically remove the chain from the parent and remove
3760 * the blockmap entry. The parent must be set modified
3761 * to remove the blockmap entry.
3763 hammer2_blockref_t *base;
3766 KKASSERT(parent != NULL);
3767 KKASSERT(parent->error == 0);
3768 KKASSERT((parent->flags & HAMMER2_CHAIN_INITIAL) == 0);
3769 error = hammer2_chain_modify(parent, mtid, 0, 0);
3774 * Calculate blockmap pointer
3776 KKASSERT(chain->flags & HAMMER2_CHAIN_ONRBTREE);
3777 hammer2_spin_ex(&chain->core.spin);
3778 hammer2_spin_ex(&parent->core.spin);
3780 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3781 atomic_add_int(&parent->core.live_count, -1);
3782 ++parent->core.generation;
3783 RB_REMOVE(hammer2_chain_tree, &parent->core.rbtree, chain);
3784 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
3785 --parent->core.chain_count;
3786 chain->parent = NULL;
3788 switch(parent->bref.type) {
3789 case HAMMER2_BREF_TYPE_INODE:
3791 * Access the inode's block array. However, there
3792 * is no block array if the inode is flagged
3796 (parent->data->ipdata.meta.op_flags &
3797 HAMMER2_OPFLAG_DIRECTDATA) == 0) {
3799 &parent->data->ipdata.u.blockset.blockref[0];
3803 count = HAMMER2_SET_COUNT;
3805 case HAMMER2_BREF_TYPE_INDIRECT:
3806 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
3808 base = &parent->data->npdata[0];
3811 count = parent->bytes / sizeof(hammer2_blockref_t);
3813 case HAMMER2_BREF_TYPE_VOLUME:
3814 base = &parent->data->voldata.
3815 sroot_blockset.blockref[0];
3816 count = HAMMER2_SET_COUNT;
3818 case HAMMER2_BREF_TYPE_FREEMAP:
3819 base = &parent->data->blkset.blockref[0];
3820 count = HAMMER2_SET_COUNT;
3825 panic("hammer2_flush_pass2: "
3826 "unrecognized blockref type: %d",
3831 * delete blockmapped chain from its parent.
3833 * The parent is not affected by any statistics in chain
3834 * which are pending synchronization. That is, there is
3835 * nothing to undo in the parent since they have not yet
3836 * been incorporated into the parent.
3838 * The parent is affected by statistics stored in inodes.
3839 * Those have already been synchronized, so they must be
3840 * undone. XXX split update possible w/delete in middle?
3843 hammer2_base_delete(parent, base, count, chain, obref);
3845 hammer2_spin_unex(&parent->core.spin);
3846 hammer2_spin_unex(&chain->core.spin);
3847 } else if (chain->flags & HAMMER2_CHAIN_ONRBTREE) {
3849 * Chain is not blockmapped but a parent is present.
3850 * Atomically remove the chain from the parent. There is
3851 * no blockmap entry to remove.
3853 * Because chain was associated with a parent but not
3854 * synchronized, the chain's *_count_up fields contain
3855 * inode adjustment statistics which must be undone.
3857 hammer2_spin_ex(&chain->core.spin);
3858 hammer2_spin_ex(&parent->core.spin);
3859 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3860 atomic_add_int(&parent->core.live_count, -1);
3861 ++parent->core.generation;
3862 RB_REMOVE(hammer2_chain_tree, &parent->core.rbtree, chain);
3863 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_ONRBTREE);
3864 --parent->core.chain_count;
3865 chain->parent = NULL;
3866 hammer2_spin_unex(&parent->core.spin);
3867 hammer2_spin_unex(&chain->core.spin);
3870 * Chain is not blockmapped and has no parent. This
3871 * is a degenerate case.
3873 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DELETED);
3880 * Create an indirect block that covers one or more of the elements in the
3881 * current parent. Either returns the existing parent with no locking or
3882 * ref changes or returns the new indirect block locked and referenced
3883 * and leaving the original parent lock/ref intact as well.
3885 * If an error occurs, NULL is returned and *errorp is set to the H2 error.
3887 * The returned chain depends on where the specified key falls.
3889 * The key/keybits for the indirect mode only needs to follow three rules:
3891 * (1) That all elements underneath it fit within its key space and
3893 * (2) That all elements outside it are outside its key space.
3895 * (3) When creating the new indirect block any elements in the current
3896 * parent that fit within the new indirect block's keyspace must be
3897 * moved into the new indirect block.
3899 * (4) The keyspace chosen for the inserted indirect block CAN cover a wider
3900 * keyspace the the current parent, but lookup/iteration rules will
3901 * ensure (and must ensure) that rule (2) for all parents leading up
3902 * to the nearest inode or the root volume header is adhered to. This
3903 * is accomplished by always recursing through matching keyspaces in
3904 * the hammer2_chain_lookup() and hammer2_chain_next() API.
3906 * The current implementation calculates the current worst-case keyspace by
3907 * iterating the current parent and then divides it into two halves, choosing
3908 * whichever half has the most elements (not necessarily the half containing
3909 * the requested key).
3911 * We can also opt to use the half with the least number of elements. This
3912 * causes lower-numbered keys (aka logical file offsets) to recurse through
3913 * fewer indirect blocks and higher-numbered keys to recurse through more.
3914 * This also has the risk of not moving enough elements to the new indirect
3915 * block and being forced to create several indirect blocks before the element
3918 * Must be called with an exclusively locked parent.
3920 * NOTE: *errorp set to HAMMER_ERROR_* flags
3922 static int hammer2_chain_indkey_freemap(hammer2_chain_t *parent,
3923 hammer2_key_t *keyp, int keybits,
3924 hammer2_blockref_t *base, int count);
3925 static int hammer2_chain_indkey_file(hammer2_chain_t *parent,
3926 hammer2_key_t *keyp, int keybits,
3927 hammer2_blockref_t *base, int count,
3929 static int hammer2_chain_indkey_dir(hammer2_chain_t *parent,
3930 hammer2_key_t *keyp, int keybits,
3931 hammer2_blockref_t *base, int count,
3935 hammer2_chain_create_indirect(hammer2_chain_t *parent,
3936 hammer2_key_t create_key, int create_bits,
3937 hammer2_tid_t mtid, int for_type, int *errorp)
3940 hammer2_blockref_t *base;
3941 hammer2_blockref_t *bref;
3942 hammer2_blockref_t bcopy;
3943 hammer2_chain_t *chain;
3944 hammer2_chain_t *ichain;
3945 hammer2_chain_t dummy;
3946 hammer2_key_t key = create_key;
3947 hammer2_key_t key_beg;
3948 hammer2_key_t key_end;
3949 hammer2_key_t key_next;
3950 int keybits = create_bits;
3958 int maxloops = 300000;
3961 * Calculate the base blockref pointer or NULL if the chain
3962 * is known to be empty. We need to calculate the array count
3963 * for RB lookups either way.
3966 KKASSERT(hammer2_mtx_owned(&parent->lock));
3969 * Pre-modify the parent now to avoid having to deal with error
3970 * processing if we tried to later (in the middle of our loop).
3972 * We are going to be moving bref's around, the indirect blocks
3973 * cannot be in an initial state. Do not pass MODIFY_OPTDATA.
3975 *errorp = hammer2_chain_modify(parent, mtid, 0, 0);
3977 kprintf("hammer2_create_indirect: error %08x %s\n",
3978 *errorp, hammer2_error_str(*errorp));
3981 KKASSERT((parent->flags & HAMMER2_CHAIN_INITIAL) == 0);
3983 /*hammer2_chain_modify(&parent, HAMMER2_MODIFY_OPTDATA);*/
3984 base = hammer2_chain_base_and_count(parent, &count);
3987 * dummy used in later chain allocation (no longer used for lookups).
3989 bzero(&dummy, sizeof(dummy));
3992 * How big should our new indirect block be? It has to be at least
3993 * as large as its parent for splits to work properly.
3995 * The freemap uses a specific indirect block size. The number of
3996 * levels are built dynamically and ultimately depend on the size
3997 * volume. Because freemap blocks are taken from the reserved areas
3998 * of the volume our goal is efficiency (fewer levels) and not so
3999 * much to save disk space.
4001 * The first indirect block level for a directory usually uses
4002 * HAMMER2_IND_BYTES_MIN (4KB = 32 directory entries). Due to
4003 * the hash mechanism, this typically gives us a nominal
4004 * 32 * 4 entries with one level of indirection.
4006 * We use HAMMER2_IND_BYTES_NOM (16KB = 128 blockrefs) for FILE
4007 * indirect blocks. The initial 4 entries in the inode gives us
4008 * 256KB. Up to 4 indirect blocks gives us 32MB. Three levels
4009 * of indirection gives us 137GB, and so forth. H2 can support
4010 * huge file sizes but they are not typical, so we try to stick
4011 * with compactness and do not use a larger indirect block size.
4013 * We could use 64KB (PBUFSIZE), giving us 512 blockrefs, but
4014 * due to the way indirect blocks are created this usually winds
4015 * up being extremely inefficient for small files. Even though
4016 * 16KB requires more levels of indirection for very large files,
4017 * the 16KB records can be ganged together into 64KB DIOs.
4019 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
4020 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
4021 nbytes = HAMMER2_FREEMAP_LEVELN_PSIZE;
4022 } else if (parent->bref.type == HAMMER2_BREF_TYPE_INODE) {
4023 if (parent->data->ipdata.meta.type ==
4024 HAMMER2_OBJTYPE_DIRECTORY)
4025 nbytes = HAMMER2_IND_BYTES_MIN; /* 4KB = 32 entries */
4027 nbytes = HAMMER2_IND_BYTES_NOM; /* 16KB = ~8MB file */
4030 nbytes = HAMMER2_IND_BYTES_NOM;
4032 if (nbytes < count * sizeof(hammer2_blockref_t)) {
4033 KKASSERT(for_type != HAMMER2_BREF_TYPE_FREEMAP_NODE &&
4034 for_type != HAMMER2_BREF_TYPE_FREEMAP_LEAF);
4035 nbytes = count * sizeof(hammer2_blockref_t);
4037 ncount = nbytes / sizeof(hammer2_blockref_t);
4040 * When creating an indirect block for a freemap node or leaf
4041 * the key/keybits must be fitted to static radix levels because
4042 * particular radix levels use particular reserved blocks in the
4045 * This routine calculates the key/radix of the indirect block
4046 * we need to create, and whether it is on the high-side or the
4050 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
4051 case HAMMER2_BREF_TYPE_FREEMAP_LEAF:
4052 keybits = hammer2_chain_indkey_freemap(parent, &key, keybits,
4055 case HAMMER2_BREF_TYPE_DATA:
4056 keybits = hammer2_chain_indkey_file(parent, &key, keybits,
4057 base, count, ncount);
4059 case HAMMER2_BREF_TYPE_DIRENT:
4060 case HAMMER2_BREF_TYPE_INODE:
4061 keybits = hammer2_chain_indkey_dir(parent, &key, keybits,
4062 base, count, ncount);
4065 panic("illegal indirect block for bref type %d", for_type);
4070 * Normalize the key for the radix being represented, keeping the
4071 * high bits and throwing away the low bits.
4073 key &= ~(((hammer2_key_t)1 << keybits) - 1);
4076 * Ok, create our new indirect block
4078 if (for_type == HAMMER2_BREF_TYPE_FREEMAP_NODE ||
4079 for_type == HAMMER2_BREF_TYPE_FREEMAP_LEAF) {
4080 dummy.bref.type = HAMMER2_BREF_TYPE_FREEMAP_NODE;
4082 dummy.bref.type = HAMMER2_BREF_TYPE_INDIRECT;
4084 dummy.bref.key = key;
4085 dummy.bref.keybits = keybits;
4086 dummy.bref.data_off = hammer2_getradix(nbytes);
4087 dummy.bref.methods =
4088 HAMMER2_ENC_CHECK(HAMMER2_DEC_CHECK(parent->bref.methods)) |
4089 HAMMER2_ENC_COMP(HAMMER2_COMP_NONE);
4091 ichain = hammer2_chain_alloc(hmp, parent->pmp, &dummy.bref);
4092 atomic_set_int(&ichain->flags, HAMMER2_CHAIN_INITIAL);
4093 hammer2_chain_lock(ichain, HAMMER2_RESOLVE_MAYBE);
4094 /* ichain has one ref at this point */
4097 * We have to mark it modified to allocate its block, but use
4098 * OPTDATA to allow it to remain in the INITIAL state. Otherwise
4099 * it won't be acted upon by the flush code.
4101 * XXX remove OPTDATA, we need a fully initialized indirect block to
4102 * be able to move the original blockref.
4104 *errorp = hammer2_chain_modify(ichain, mtid, 0, 0);
4106 kprintf("hammer2_alloc_indirect: error %08x %s\n",
4107 *errorp, hammer2_error_str(*errorp));
4108 hammer2_chain_unlock(ichain);
4109 hammer2_chain_drop(ichain);
4112 KKASSERT((ichain->flags & HAMMER2_CHAIN_INITIAL) == 0);
4115 * Iterate the original parent and move the matching brefs into
4116 * the new indirect block.
4118 * XXX handle flushes.
4121 key_end = HAMMER2_KEY_MAX;
4122 key_next = 0; /* avoid gcc warnings */
4123 hammer2_spin_ex(&parent->core.spin);
4129 * Parent may have been modified, relocating its block array.
4130 * Reload the base pointer.
4132 base = hammer2_chain_base_and_count(parent, &count);
4134 if (++loops > 100000) {
4135 hammer2_spin_unex(&parent->core.spin);
4136 panic("excessive loops r=%d p=%p base/count %p:%d %016jx\n",
4137 reason, parent, base, count, key_next);
4141 * NOTE: spinlock stays intact, returned chain (if not NULL)
4142 * is not referenced or locked which means that we
4143 * cannot safely check its flagged / deletion status
4146 chain = hammer2_combined_find(parent, base, count,
4150 generation = parent->core.generation;
4153 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
4156 * Skip keys that are not within the key/radix of the new
4157 * indirect block. They stay in the parent.
4159 if ((~(((hammer2_key_t)1 << keybits) - 1) &
4160 (key ^ bref->key)) != 0) {
4161 goto next_key_spinlocked;
4165 * Load the new indirect block by acquiring the related
4166 * chains (potentially from media as it might not be
4167 * in-memory). Then move it to the new parent (ichain).
4169 * chain is referenced but not locked. We must lock the
4170 * chain to obtain definitive state.
4175 * Use chain already present in the RBTREE
4177 hammer2_chain_ref(chain);
4178 hammer2_spin_unex(&parent->core.spin);
4179 hammer2_chain_lock(chain, HAMMER2_RESOLVE_NEVER);
4182 * Get chain for blockref element. _get returns NULL
4183 * on insertion race.
4185 hammer2_spin_unex(&parent->core.spin);
4186 chain = hammer2_chain_get(parent, generation, &bcopy,
4187 HAMMER2_RESOLVE_NEVER);
4188 if (chain == NULL) {
4190 hammer2_spin_ex(&parent->core.spin);
4196 * This is always live so if the chain has been deleted
4197 * we raced someone and we have to retry.
4199 * NOTE: Lookups can race delete-duplicate because
4200 * delete-duplicate does not lock the parent's core
4201 * (they just use the spinlock on the core).
4203 * (note reversed logic for this one)
4205 if (bcmp(&bcopy, &chain->bref, sizeof(bcopy)) ||
4206 chain->parent != parent ||
4207 (chain->flags & HAMMER2_CHAIN_DELETED)) {
4208 hammer2_chain_unlock(chain);
4209 hammer2_chain_drop(chain);
4210 if (hammer2_debug & 0x0040) {
4211 kprintf("LOST PARENT RETRY "
4212 "RETRY (%p,%p)->%p %08x\n",
4213 parent, chain->parent, chain, chain->flags);
4215 hammer2_spin_ex(&parent->core.spin);
4220 * Shift the chain to the indirect block.
4222 * WARNING! No reason for us to load chain data, pass NOSTATS
4223 * to prevent delete/insert from trying to access
4224 * inode stats (and thus asserting if there is no
4225 * chain->data loaded).
4227 * WARNING! The (parent, chain) deletion may modify the parent
4228 * and invalidate the base pointer.
4230 * WARNING! Parent must already be marked modified, so we
4231 * can assume that chain_delete always suceeds.
4233 * WARNING! hammer2_chain_repchange() does not have to be
4234 * called (and doesn't work anyway because we are
4235 * only doing a partial shift). A recursion that is
4236 * in-progress can continue at the current parent
4237 * and will be able to properly find its next key.
4239 error = hammer2_chain_delete_obref(parent, chain, mtid, 0,
4241 KKASSERT(error == 0);
4242 hammer2_chain_rename_obref(&ichain, chain, mtid, 0, &bcopy);
4243 hammer2_chain_unlock(chain);
4244 hammer2_chain_drop(chain);
4245 KKASSERT(parent->refs > 0);
4247 base = NULL; /* safety */
4248 hammer2_spin_ex(&parent->core.spin);
4249 next_key_spinlocked:
4250 if (--maxloops == 0)
4251 panic("hammer2_chain_create_indirect: maxloops");
4253 if (key_next == 0 || key_next > key_end)
4258 hammer2_spin_unex(&parent->core.spin);
4261 * Insert the new indirect block into the parent now that we've
4262 * cleared out some entries in the parent. We calculated a good
4263 * insertion index in the loop above (ichain->index).
4265 * We don't have to set UPDATE here because we mark ichain
4266 * modified down below (so the normal modified -> flush -> set-moved
4267 * sequence applies).
4269 * The insertion shouldn't race as this is a completely new block
4270 * and the parent is locked.
4272 base = NULL; /* safety, parent modify may change address */
4273 KKASSERT((ichain->flags & HAMMER2_CHAIN_ONRBTREE) == 0);
4274 KKASSERT(parent->core.live_count < count);
4275 hammer2_chain_insert(parent, ichain,
4276 HAMMER2_CHAIN_INSERT_SPIN |
4277 HAMMER2_CHAIN_INSERT_LIVE,
4281 * Make sure flushes propogate after our manual insertion.
4283 hammer2_chain_setflush(ichain);
4284 hammer2_chain_setflush(parent);
4287 * Figure out what to return.
4289 if (~(((hammer2_key_t)1 << keybits) - 1) &
4290 (create_key ^ key)) {
4292 * Key being created is outside the key range,
4293 * return the original parent.
4295 hammer2_chain_unlock(ichain);
4296 hammer2_chain_drop(ichain);
4299 * Otherwise its in the range, return the new parent.
4300 * (leave both the new and old parent locked).
4309 * Do maintenance on an indirect chain. Both parent and chain are locked.
4311 * Returns non-zero if (chain) is deleted, either due to being empty or
4312 * because its children were safely moved into the parent.
4315 hammer2_chain_indirect_maintenance(hammer2_chain_t *parent,
4316 hammer2_chain_t *chain)
4318 hammer2_blockref_t *chain_base;
4319 hammer2_blockref_t *base;
4320 hammer2_blockref_t *bref;
4321 hammer2_blockref_t bcopy;
4322 hammer2_key_t key_next;
4323 hammer2_key_t key_beg;
4324 hammer2_key_t key_end;
4325 hammer2_chain_t *sub;
4332 * Make sure we have an accurate live_count
4334 if ((chain->flags & (HAMMER2_CHAIN_INITIAL |
4335 HAMMER2_CHAIN_COUNTEDBREFS)) == 0) {
4336 base = &chain->data->npdata[0];
4337 count = chain->bytes / sizeof(hammer2_blockref_t);
4338 hammer2_chain_countbrefs(chain, base, count);
4342 * If the indirect block is empty we can delete it.
4343 * (ignore deletion error)
4345 if (chain->core.live_count == 0 && RB_EMPTY(&chain->core.rbtree)) {
4346 hammer2_chain_delete(parent, chain,
4347 chain->bref.modify_tid,
4348 HAMMER2_DELETE_PERMANENT);
4349 hammer2_chain_repchange(parent, chain);
4353 base = hammer2_chain_base_and_count(parent, &count);
4355 if ((parent->flags & (HAMMER2_CHAIN_INITIAL |
4356 HAMMER2_CHAIN_COUNTEDBREFS)) == 0) {
4357 hammer2_chain_countbrefs(parent, base, count);
4361 * Determine if we can collapse chain into parent, calculate
4362 * hysteresis for chain emptiness.
4364 if (parent->core.live_count + chain->core.live_count - 1 > count)
4366 chain_count = chain->bytes / sizeof(hammer2_blockref_t);
4367 if (chain->core.live_count > chain_count * 3 / 4)
4371 * Ok, theoretically we can collapse chain's contents into
4372 * parent. chain is locked, but any in-memory children of chain
4373 * are not. For this to work, we must be able to dispose of any
4374 * in-memory children of chain.
4376 * For now require that there are no in-memory children of chain.
4378 * WARNING! Both chain and parent must remain locked across this
4383 * Parent must be marked modified. Don't try to collapse it if we
4384 * can't mark it modified. Once modified, destroy chain to make room
4385 * and to get rid of what will be a conflicting key (this is included
4386 * in the calculation above). Finally, move the children of chain
4387 * into chain's parent.
4389 * This order creates an accounting problem for bref.embed.stats
4390 * because we destroy chain before we remove its children. Any
4391 * elements whos blockref is already synchronized will be counted
4392 * twice. To deal with the problem we clean out chain's stats prior
4395 error = hammer2_chain_modify(parent, 0, 0, 0);
4397 krateprintf(&krate_h2me, "hammer2: indirect_maint: %s\n",
4398 hammer2_error_str(error));
4401 error = hammer2_chain_modify(chain, chain->bref.modify_tid, 0, 0);
4403 krateprintf(&krate_h2me, "hammer2: indirect_maint: %s\n",
4404 hammer2_error_str(error));
4408 chain->bref.embed.stats.inode_count = 0;
4409 chain->bref.embed.stats.data_count = 0;
4410 error = hammer2_chain_delete(parent, chain,
4411 chain->bref.modify_tid,
4412 HAMMER2_DELETE_PERMANENT);
4413 KKASSERT(error == 0);
4416 * The combined_find call requires core.spin to be held. One would
4417 * think there wouldn't be any conflicts since we hold chain
4418 * exclusively locked, but the caching mechanism for 0-ref children
4419 * does not require a chain lock.
4421 hammer2_spin_ex(&chain->core.spin);
4425 key_end = HAMMER2_KEY_MAX;
4427 chain_base = &chain->data->npdata[0];
4428 chain_count = chain->bytes / sizeof(hammer2_blockref_t);
4429 sub = hammer2_combined_find(chain, chain_base, chain_count,
4433 generation = chain->core.generation;
4436 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
4440 hammer2_chain_ref(sub);
4441 hammer2_spin_unex(&chain->core.spin);
4442 hammer2_chain_lock(sub, HAMMER2_RESOLVE_NEVER);
4444 hammer2_spin_unex(&chain->core.spin);
4445 sub = hammer2_chain_get(chain, generation, &bcopy,
4446 HAMMER2_RESOLVE_NEVER);
4448 hammer2_spin_ex(&chain->core.spin);
4452 if (bcmp(&bcopy, &sub->bref, sizeof(bcopy)) ||
4453 sub->parent != chain ||
4454 (sub->flags & HAMMER2_CHAIN_DELETED)) {
4455 hammer2_chain_unlock(sub);
4456 hammer2_chain_drop(sub);
4457 hammer2_spin_ex(&chain->core.spin);
4458 sub = NULL; /* safety */
4461 error = hammer2_chain_delete_obref(chain, sub,
4462 sub->bref.modify_tid, 0,
4464 KKASSERT(error == 0);
4465 hammer2_chain_rename_obref(&parent, sub,
4466 sub->bref.modify_tid,
4467 HAMMER2_INSERT_SAMEPARENT, &bcopy);
4468 hammer2_chain_unlock(sub);
4469 hammer2_chain_drop(sub);
4470 hammer2_spin_ex(&chain->core.spin);
4476 hammer2_spin_unex(&chain->core.spin);
4478 hammer2_chain_repchange(parent, chain);
4484 * Freemap indirect blocks
4486 * Calculate the keybits and highside/lowside of the freemap node the
4487 * caller is creating.
4489 * This routine will specify the next higher-level freemap key/radix
4490 * representing the lowest-ordered set. By doing so, eventually all
4491 * low-ordered sets will be moved one level down.
4493 * We have to be careful here because the freemap reserves a limited
4494 * number of blocks for a limited number of levels. So we can't just
4495 * push indiscriminately.
4498 hammer2_chain_indkey_freemap(hammer2_chain_t *parent, hammer2_key_t *keyp,
4499 int keybits, hammer2_blockref_t *base, int count)
4501 hammer2_chain_t *chain;
4502 hammer2_blockref_t *bref;
4504 hammer2_key_t key_beg;
4505 hammer2_key_t key_end;
4506 hammer2_key_t key_next;
4509 int maxloops = 300000;
4517 * Calculate the range of keys in the array being careful to skip
4518 * slots which are overridden with a deletion.
4521 key_end = HAMMER2_KEY_MAX;
4522 hammer2_spin_ex(&parent->core.spin);
4525 if (--maxloops == 0) {
4526 panic("indkey_freemap shit %p %p:%d\n",
4527 parent, base, count);
4529 chain = hammer2_combined_find(parent, base, count,
4541 * Skip deleted chains.
4543 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
4544 if (key_next == 0 || key_next > key_end)
4551 * Use the full live (not deleted) element for the scan
4552 * iteration. HAMMER2 does not allow partial replacements.
4554 * XXX should be built into hammer2_combined_find().
4556 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
4558 if (keybits > bref->keybits) {
4560 keybits = bref->keybits;
4561 } else if (keybits == bref->keybits && bref->key < key) {
4568 hammer2_spin_unex(&parent->core.spin);
4571 * Return the keybits for a higher-level FREEMAP_NODE covering
4575 case HAMMER2_FREEMAP_LEVEL0_RADIX:
4576 keybits = HAMMER2_FREEMAP_LEVEL1_RADIX;
4578 case HAMMER2_FREEMAP_LEVEL1_RADIX:
4579 keybits = HAMMER2_FREEMAP_LEVEL2_RADIX;
4581 case HAMMER2_FREEMAP_LEVEL2_RADIX:
4582 keybits = HAMMER2_FREEMAP_LEVEL3_RADIX;
4584 case HAMMER2_FREEMAP_LEVEL3_RADIX:
4585 keybits = HAMMER2_FREEMAP_LEVEL4_RADIX;
4587 case HAMMER2_FREEMAP_LEVEL4_RADIX:
4588 keybits = HAMMER2_FREEMAP_LEVEL5_RADIX;
4590 case HAMMER2_FREEMAP_LEVEL5_RADIX:
4591 panic("hammer2_chain_indkey_freemap: level too high");
4594 panic("hammer2_chain_indkey_freemap: bad radix");
4603 * File indirect blocks
4605 * Calculate the key/keybits for the indirect block to create by scanning
4606 * existing keys. The key being created is also passed in *keyp and can be
4607 * inside or outside the indirect block. Regardless, the indirect block
4608 * must hold at least two keys in order to guarantee sufficient space.
4610 * We use a modified version of the freemap's fixed radix tree, but taylored
4611 * for file data. Basically we configure an indirect block encompassing the
4615 hammer2_chain_indkey_file(hammer2_chain_t *parent, hammer2_key_t *keyp,
4616 int keybits, hammer2_blockref_t *base, int count,
4619 hammer2_chain_t *chain;
4620 hammer2_blockref_t *bref;
4622 hammer2_key_t key_beg;
4623 hammer2_key_t key_end;
4624 hammer2_key_t key_next;
4628 int maxloops = 300000;
4636 * Calculate the range of keys in the array being careful to skip
4637 * slots which are overridden with a deletion.
4639 * Locate the smallest key.
4642 key_end = HAMMER2_KEY_MAX;
4643 hammer2_spin_ex(&parent->core.spin);
4646 if (--maxloops == 0) {
4647 panic("indkey_freemap shit %p %p:%d\n",
4648 parent, base, count);
4650 chain = hammer2_combined_find(parent, base, count,
4662 * Skip deleted chains.
4664 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
4665 if (key_next == 0 || key_next > key_end)
4672 * Use the full live (not deleted) element for the scan
4673 * iteration. HAMMER2 does not allow partial replacements.
4675 * XXX should be built into hammer2_combined_find().
4677 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
4679 if (keybits > bref->keybits) {
4681 keybits = bref->keybits;
4682 } else if (keybits == bref->keybits && bref->key < key) {
4689 hammer2_spin_unex(&parent->core.spin);
4692 * Calculate the static keybits for a higher-level indirect block
4693 * that contains the key.
4698 case HAMMER2_IND_BYTES_MIN / sizeof(hammer2_blockref_t):
4699 nradix = HAMMER2_IND_RADIX_MIN - HAMMER2_BLOCKREF_RADIX;
4701 case HAMMER2_IND_BYTES_NOM / sizeof(hammer2_blockref_t):
4702 nradix = HAMMER2_IND_RADIX_NOM - HAMMER2_BLOCKREF_RADIX;
4704 case HAMMER2_IND_BYTES_MAX / sizeof(hammer2_blockref_t):
4705 nradix = HAMMER2_IND_RADIX_MAX - HAMMER2_BLOCKREF_RADIX;
4708 panic("bad ncount %d\n", ncount);
4714 * The largest radix that can be returned for an indirect block is
4715 * 63 bits. (The largest practical indirect block radix is actually
4716 * 62 bits because the top-level inode or volume root contains four
4717 * entries, but allow 63 to be returned).
4722 return keybits + nradix;
4728 * Directory indirect blocks.
4730 * Covers both the inode index (directory of inodes), and directory contents
4731 * (filenames hardlinked to inodes).
4733 * Because directory keys are hashed we generally try to cut the space in
4734 * half. We accomodate the inode index (which tends to have linearly
4735 * increasing inode numbers) by ensuring that the keyspace is at least large
4736 * enough to fill up the indirect block being created.
4739 hammer2_chain_indkey_dir(hammer2_chain_t *parent, hammer2_key_t *keyp,
4740 int keybits, hammer2_blockref_t *base, int count,
4743 hammer2_blockref_t *bref;
4744 hammer2_chain_t *chain;
4745 hammer2_key_t key_beg;
4746 hammer2_key_t key_end;
4747 hammer2_key_t key_next;
4752 int maxloops = 300000;
4755 * NOTE: We can't take a shortcut here anymore for inodes because
4756 * the root directory can contain a mix of inodes and directory
4757 * entries (we used to just return 63 if parent->bref.type was
4758 * HAMMER2_BREF_TYPE_INODE.
4765 * Calculate the range of keys in the array being careful to skip
4766 * slots which are overridden with a deletion.
4769 key_end = HAMMER2_KEY_MAX;
4770 hammer2_spin_ex(&parent->core.spin);
4773 if (--maxloops == 0) {
4774 panic("indkey_freemap shit %p %p:%d\n",
4775 parent, base, count);
4777 chain = hammer2_combined_find(parent, base, count,
4791 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
4792 if (key_next == 0 || key_next > key_end)
4799 * Use the full live (not deleted) element for the scan
4800 * iteration. HAMMER2 does not allow partial replacements.
4802 * XXX should be built into hammer2_combined_find().
4804 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
4807 * Expand our calculated key range (key, keybits) to fit
4808 * the scanned key. nkeybits represents the full range
4809 * that we will later cut in half (two halves @ nkeybits - 1).
4812 if (nkeybits < bref->keybits) {
4813 if (bref->keybits > 64) {
4814 kprintf("bad bref chain %p bref %p\n",
4818 nkeybits = bref->keybits;
4820 while (nkeybits < 64 &&
4821 (~(((hammer2_key_t)1 << nkeybits) - 1) &
4822 (key ^ bref->key)) != 0) {
4827 * If the new key range is larger we have to determine
4828 * which side of the new key range the existing keys fall
4829 * under by checking the high bit, then collapsing the
4830 * locount into the hicount or vise-versa.
4832 if (keybits != nkeybits) {
4833 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) {
4844 * The newly scanned key will be in the lower half or the
4845 * upper half of the (new) key range.
4847 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key)
4856 hammer2_spin_unex(&parent->core.spin);
4857 bref = NULL; /* now invalid (safety) */
4860 * Adjust keybits to represent half of the full range calculated
4861 * above (radix 63 max) for our new indirect block.
4866 * Expand keybits to hold at least ncount elements. ncount will be
4867 * a power of 2. This is to try to completely fill leaf nodes (at
4868 * least for keys which are not hashes).
4870 * We aren't counting 'in' or 'out', we are counting 'high side'
4871 * and 'low side' based on the bit at (1LL << keybits). We want
4872 * everything to be inside in these cases so shift it all to
4873 * the low or high side depending on the new high bit.
4875 while (((hammer2_key_t)1 << keybits) < ncount) {
4877 if (key & ((hammer2_key_t)1 << keybits)) {
4886 if (hicount > locount)
4887 key |= (hammer2_key_t)1 << keybits;
4889 key &= ~(hammer2_key_t)1 << keybits;
4899 * Directory indirect blocks.
4901 * Covers both the inode index (directory of inodes), and directory contents
4902 * (filenames hardlinked to inodes).
4904 * Because directory keys are hashed we generally try to cut the space in
4905 * half. We accomodate the inode index (which tends to have linearly
4906 * increasing inode numbers) by ensuring that the keyspace is at least large
4907 * enough to fill up the indirect block being created.
4910 hammer2_chain_indkey_dir(hammer2_chain_t *parent, hammer2_key_t *keyp,
4911 int keybits, hammer2_blockref_t *base, int count,
4914 hammer2_blockref_t *bref;
4915 hammer2_chain_t *chain;
4916 hammer2_key_t key_beg;
4917 hammer2_key_t key_end;
4918 hammer2_key_t key_next;
4923 int maxloops = 300000;
4926 * Shortcut if the parent is the inode. In this situation the
4927 * parent has 4+1 directory entries and we are creating an indirect
4928 * block capable of holding many more.
4930 if (parent->bref.type == HAMMER2_BREF_TYPE_INODE) {
4939 * Calculate the range of keys in the array being careful to skip
4940 * slots which are overridden with a deletion.
4943 key_end = HAMMER2_KEY_MAX;
4944 hammer2_spin_ex(&parent->core.spin);
4947 if (--maxloops == 0) {
4948 panic("indkey_freemap shit %p %p:%d\n",
4949 parent, base, count);
4951 chain = hammer2_combined_find(parent, base, count,
4965 if (chain && (chain->flags & HAMMER2_CHAIN_DELETED)) {
4966 if (key_next == 0 || key_next > key_end)
4973 * Use the full live (not deleted) element for the scan
4974 * iteration. HAMMER2 does not allow partial replacements.
4976 * XXX should be built into hammer2_combined_find().
4978 key_next = bref->key + ((hammer2_key_t)1 << bref->keybits);
4981 * Expand our calculated key range (key, keybits) to fit
4982 * the scanned key. nkeybits represents the full range
4983 * that we will later cut in half (two halves @ nkeybits - 1).
4986 if (nkeybits < bref->keybits) {
4987 if (bref->keybits > 64) {
4988 kprintf("bad bref chain %p bref %p\n",
4992 nkeybits = bref->keybits;
4994 while (nkeybits < 64 &&
4995 (~(((hammer2_key_t)1 << nkeybits) - 1) &
4996 (key ^ bref->key)) != 0) {
5001 * If the new key range is larger we have to determine
5002 * which side of the new key range the existing keys fall
5003 * under by checking the high bit, then collapsing the
5004 * locount into the hicount or vise-versa.
5006 if (keybits != nkeybits) {
5007 if (((hammer2_key_t)1 << (nkeybits - 1)) & key) {
5018 * The newly scanned key will be in the lower half or the
5019 * upper half of the (new) key range.
5021 if (((hammer2_key_t)1 << (nkeybits - 1)) & bref->key)
5030 hammer2_spin_unex(&parent->core.spin);
5031 bref = NULL; /* now invalid (safety) */
5034 * Adjust keybits to represent half of the full range calculated
5035 * above (radix 63 max) for our new indirect block.
5040 * Expand keybits to hold at least ncount elements. ncount will be
5041 * a power of 2. This is to try to completely fill leaf nodes (at
5042 * least for keys which are not hashes).
5044 * We aren't counting 'in' or 'out', we are counting 'high side'
5045 * and 'low side' based on the bit at (1LL << keybits). We want
5046 * everything to be inside in these cases so shift it all to
5047 * the low or high side depending on the new high bit.
5049 while (((hammer2_key_t)1 << keybits) < ncount) {
5051 if (key & ((hammer2_key_t)1 << keybits)) {
5060 if (hicount > locount)
5061 key |= (hammer2_key_t)1 << keybits;
5063 key &= ~(hammer2_key_t)1 << keybits;
5073 * Sets CHAIN_DELETED and remove the chain's blockref from the parent if
5076 * Both parent and chain must be locked exclusively.
5078 * This function will modify the parent if the blockref requires removal
5079 * from the parent's block table.
5081 * This function is NOT recursive. Any entity already pushed into the
5082 * chain (such as an inode) may still need visibility into its contents,
5083 * as well as the ability to read and modify the contents. For example,
5084 * for an unlinked file which is still open.
5086 * Also note that the flusher is responsible for cleaning up empty
5090 hammer2_chain_delete(hammer2_chain_t *parent, hammer2_chain_t *chain,
5091 hammer2_tid_t mtid, int flags)
5095 KKASSERT(hammer2_mtx_owned(&chain->lock));
5098 * Nothing to do if already marked.
5100 * We need the spinlock on the core whos RBTREE contains chain
5101 * to protect against races.
5103 if ((chain->flags & HAMMER2_CHAIN_DELETED) == 0) {
5104 KKASSERT((chain->flags & HAMMER2_CHAIN_DELETED) == 0 &&
5105 chain->parent == parent);
5106 error = _hammer2_chain_delete_helper(parent, chain,
5111 * Permanent deletions mark the chain as destroyed.
5113 * NOTE: We do not setflush the chain unless the deletion is
5114 * permanent, since the deletion of a chain does not actually
5115 * require it to be flushed.
5118 if (flags & HAMMER2_DELETE_PERMANENT) {
5119 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DESTROY);
5120 hammer2_chain_setflush(chain);
5128 hammer2_chain_delete_obref(hammer2_chain_t *parent, hammer2_chain_t *chain,
5129 hammer2_tid_t mtid, int flags,
5130 hammer2_blockref_t *obref)
5134 KKASSERT(hammer2_mtx_owned(&chain->lock));
5137 * Nothing to do if already marked.
5139 * We need the spinlock on the core whos RBTREE contains chain
5140 * to protect against races.
5143 if ((chain->flags & HAMMER2_CHAIN_DELETED) == 0) {
5144 KKASSERT((chain->flags & HAMMER2_CHAIN_DELETED) == 0 &&
5145 chain->parent == parent);
5146 error = _hammer2_chain_delete_helper(parent, chain,
5147 mtid, flags, obref);
5151 * Permanent deletions mark the chain as destroyed.
5153 * NOTE: We do not setflush the chain unless the deletion is
5154 * permanent, since the deletion of a chain does not actually
5155 * require it to be flushed.
5158 if (flags & HAMMER2_DELETE_PERMANENT) {
5159 atomic_set_int(&chain->flags, HAMMER2_CHAIN_DESTROY);
5160 hammer2_chain_setflush(chain);
5168 * Returns the index of the nearest element in the blockref array >= elm.
5169 * Returns (count) if no element could be found.
5171 * Sets *key_nextp to the next key for loop purposes but does not modify
5172 * it if the next key would be higher than the current value of *key_nextp.
5173 * Note that *key_nexp can overflow to 0, which should be tested by the
5176 * WARNING! Must be called with parent's spinlock held. Spinlock remains
5177 * held through the operation.
5180 hammer2_base_find(hammer2_chain_t *parent,
5181 hammer2_blockref_t *base, int count,
5182 hammer2_key_t *key_nextp,
5183 hammer2_key_t key_beg, hammer2_key_t key_end)
5185 hammer2_blockref_t *scan;
5186 hammer2_key_t scan_end;
5191 * Require the live chain's already have their core's counted
5192 * so we can optimize operations.
5194 KKASSERT(parent->flags & HAMMER2_CHAIN_COUNTEDBREFS);
5199 if (count == 0 || base == NULL)
5203 * Sequential optimization using parent->cache_index. This is
5204 * the most likely scenario.
5206 * We can avoid trailing empty entries on live chains, otherwise
5207 * we might have to check the whole block array.
5209 i = parent->cache_index; /* SMP RACE OK */
5211 limit = parent->core.live_zero;
5216 KKASSERT(i < count);
5222 while (i > 0 && (scan->type == 0 || scan->key > key_beg)) {
5226 parent->cache_index = i;
5229 * Search forwards, stop when we find a scan element which
5230 * encloses the key or until we know that there are no further
5234 if (scan->type != 0) {
5235 scan_end = scan->key +
5236 ((hammer2_key_t)1 << scan->keybits) - 1;
5237 if (scan->key > key_beg || scan_end >= key_beg)
5246 parent->cache_index = i;
5250 scan_end = scan->key +
5251 ((hammer2_key_t)1 << scan->keybits);
5252 if (scan_end && (*key_nextp > scan_end ||
5254 *key_nextp = scan_end;
5262 * Do a combined search and return the next match either from the blockref
5263 * array or from the in-memory chain. Sets *bresp to the returned bref in
5264 * both cases, or sets it to NULL if the search exhausted. Only returns
5265 * a non-NULL chain if the search matched from the in-memory chain.
5267 * When no in-memory chain has been found and a non-NULL bref is returned
5271 * The returned chain is not locked or referenced. Use the returned bref
5272 * to determine if the search exhausted or not. Iterate if the base find
5273 * is chosen but matches a deleted chain.
5275 * WARNING! Must be called with parent's spinlock held. Spinlock remains
5276 * held through the operation.
5279 hammer2_combined_find(hammer2_chain_t *parent,
5280 hammer2_blockref_t *base, int count,
5281 hammer2_key_t *key_nextp,
5282 hammer2_key_t key_beg, hammer2_key_t key_end,
5283 hammer2_blockref_t **bresp)
5285 hammer2_blockref_t *bref;
5286 hammer2_chain_t *chain;
5290 * Lookup in block array and in rbtree.
5292 *key_nextp = key_end + 1;
5293 i = hammer2_base_find(parent, base, count, key_nextp,
5295 chain = hammer2_chain_find(parent, key_nextp, key_beg, key_end);
5300 if (i == count && chain == NULL) {
5306 * Only chain matched.
5309 bref = &chain->bref;
5314 * Only blockref matched.
5316 if (chain == NULL) {
5322 * Both in-memory and blockref matched, select the nearer element.
5324 * If both are flush with the left-hand side or both are the
5325 * same distance away, select the chain. In this situation the
5326 * chain must have been loaded from the matching blockmap.
5328 if ((chain->bref.key <= key_beg && base[i].key <= key_beg) ||
5329 chain->bref.key == base[i].key) {
5330 KKASSERT(chain->bref.key == base[i].key);
5331 bref = &chain->bref;
5336 * Select the nearer key
5338 if (chain->bref.key < base[i].key) {
5339 bref = &chain->bref;
5346 * If the bref is out of bounds we've exhausted our search.
5349 if (bref->key > key_end) {
5359 * Locate the specified block array element and delete it. The element
5362 * The spin lock on the related chain must be held.
5364 * NOTE: live_count was adjusted when the chain was deleted, so it does not
5365 * need to be adjusted when we commit the media change.
5368 hammer2_base_delete(hammer2_chain_t *parent,
5369 hammer2_blockref_t *base, int count,
5370 hammer2_chain_t *chain,
5371 hammer2_blockref_t *obref)
5373 hammer2_blockref_t *elm = &chain->bref;
5374 hammer2_blockref_t *scan;
5375 hammer2_key_t key_next;
5379 * Delete element. Expect the element to exist.
5381 * XXX see caller, flush code not yet sophisticated enough to prevent
5382 * re-flushed in some cases.
5384 key_next = 0; /* max range */
5385 i = hammer2_base_find(parent, base, count, &key_next,
5386 elm->key, elm->key);
5388 if (i == count || scan->type == 0 ||
5389 scan->key != elm->key ||
5390 ((chain->flags & HAMMER2_CHAIN_BMAPUPD) == 0 &&
5391 scan->keybits != elm->keybits)) {
5392 hammer2_spin_unex(&parent->core.spin);
5393 panic("delete base %p element not found at %d/%d elm %p\n",
5394 base, i, count, elm);
5399 * Update stats and zero the entry.
5401 * NOTE: Handle radix == 0 (0 bytes) case.
5403 if ((int)(scan->data_off & HAMMER2_OFF_MASK_RADIX)) {
5404 parent->bref.embed.stats.data_count -= (hammer2_off_t)1 <<
5405 (int)(scan->data_off & HAMMER2_OFF_MASK_RADIX);
5407 switch(scan->type) {
5408 case HAMMER2_BREF_TYPE_INODE:
5409 --parent->bref.embed.stats.inode_count;
5411 case HAMMER2_BREF_TYPE_DATA:
5412 if (parent->bref.leaf_count == HAMMER2_BLOCKREF_LEAF_MAX) {
5413 atomic_set_int(&chain->flags,
5414 HAMMER2_CHAIN_HINT_LEAF_COUNT);
5416 if (parent->bref.leaf_count)
5417 --parent->bref.leaf_count;
5420 case HAMMER2_BREF_TYPE_INDIRECT:
5421 if (scan->type != HAMMER2_BREF_TYPE_DATA) {
5422 parent->bref.embed.stats.data_count -=
5423 scan->embed.stats.data_count;
5424 parent->bref.embed.stats.inode_count -=
5425 scan->embed.stats.inode_count;
5427 if (scan->type == HAMMER2_BREF_TYPE_INODE)
5429 if (parent->bref.leaf_count == HAMMER2_BLOCKREF_LEAF_MAX) {
5430 atomic_set_int(&chain->flags,
5431 HAMMER2_CHAIN_HINT_LEAF_COUNT);
5433 if (parent->bref.leaf_count <= scan->leaf_count)
5434 parent->bref.leaf_count = 0;
5436 parent->bref.leaf_count -= scan->leaf_count;
5439 case HAMMER2_BREF_TYPE_DIRENT:
5440 if (parent->bref.leaf_count == HAMMER2_BLOCKREF_LEAF_MAX) {
5441 atomic_set_int(&chain->flags,
5442 HAMMER2_CHAIN_HINT_LEAF_COUNT);
5444 if (parent->bref.leaf_count)
5445 --parent->bref.leaf_count;
5453 bzero(scan, sizeof(*scan));
5456 * We can only optimize parent->core.live_zero for live chains.
5458 if (parent->core.live_zero == i + 1) {
5459 while (--i >= 0 && base[i].type == 0)
5461 parent->core.live_zero = i + 1;
5465 * Clear appropriate blockmap flags in chain.
5467 atomic_clear_int(&chain->flags, HAMMER2_CHAIN_BMAPPED |
5468 HAMMER2_CHAIN_BMAPUPD);
5472 * Insert the specified element. The block array must not already have the
5473 * element and must have space available for the insertion.
5475 * The spin lock on the related chain must be held.
5477 * NOTE: live_count was adjusted when the chain was deleted, so it does not
5478 * need to be adjusted when we commit the media change.
5481 hammer2_base_insert(hammer2_chain_t *parent,
5482 hammer2_blockref_t *base, int count,
5483 hammer2_chain_t *chain, hammer2_blockref_t *elm)
5485 hammer2_key_t key_next;
5494 * Insert new element. Expect the element to not already exist
5495 * unless we are replacing it.
5497 * XXX see caller, flush code not yet sophisticated enough to prevent
5498 * re-flushed in some cases.
5500 key_next = 0; /* max range */
5501 i = hammer2_base_find(parent, base, count, &key_next,
5502 elm->key, elm->key);
5505 * Shortcut fill optimization, typical ordered insertion(s) may not
5508 KKASSERT(i >= 0 && i <= count);
5511 * Set appropriate blockmap flags in chain (if not NULL)
5514 atomic_set_int(&chain->flags, HAMMER2_CHAIN_BMAPPED);
5517 * Update stats and zero the entry
5519 if ((int)(elm->data_off & HAMMER2_OFF_MASK_RADIX)) {
5520 parent->bref.embed.stats.data_count += (hammer2_off_t)1 <<
5521 (int)(elm->data_off & HAMMER2_OFF_MASK_RADIX);
5524 case HAMMER2_BREF_TYPE_INODE:
5525 ++parent->bref.embed.stats.inode_count;
5527 case HAMMER2_BREF_TYPE_DATA:
5528 if (parent->bref.leaf_count != HAMMER2_BLOCKREF_LEAF_MAX)
5529 ++parent->bref.leaf_count;
5531 case HAMMER2_BREF_TYPE_INDIRECT:
5532 if (elm->type != HAMMER2_BREF_TYPE_DATA) {
5533 parent->bref.embed.stats.data_count +=
5534 elm->embed.stats.data_count;
5535 parent->bref.embed.stats.inode_count +=
5536 elm->embed.stats.inode_count;
5538 if (elm->type == HAMMER2_BREF_TYPE_INODE)
5540 if (parent->bref.leaf_count + elm->leaf_count <
5541 HAMMER2_BLOCKREF_LEAF_MAX) {
5542 parent->bref.leaf_count += elm->leaf_count;
5544 parent->bref.leaf_count = HAMMER2_BLOCKREF_LEAF_MAX;
5547 case HAMMER2_BREF_TYPE_DIRENT:
5548 if (parent->bref.leaf_count != HAMMER2_BLOCKREF_LEAF_MAX)
5549 ++parent->bref.leaf_count;
5557 * We can only optimize parent->core.live_zero for live chains.
5559 if (i == count && parent->core.live_zero < count) {
5560 i = parent->core.live_zero++;
5565 xkey = elm->key + ((hammer2_key_t)1 << elm->keybits) - 1;
5566 if (i != count && (base[i].key < elm->key || xkey >= base[i].key)) {
5567 hammer2_spin_unex(&parent->core.spin);
5568 panic("insert base %p overlapping elements at %d elm %p\n",
5573 * Try to find an empty slot before or after.
5577 while (j > 0 || k < count) {
5579 if (j >= 0 && base[j].type == 0) {
5583 bcopy(&base[j+1], &base[j],
5584 (i - j - 1) * sizeof(*base));
5590 if (k < count && base[k].type == 0) {
5591 bcopy(&base[i], &base[i+1],
5592 (k - i) * sizeof(hammer2_blockref_t));
5596 * We can only update parent->core.live_zero for live
5599 if (parent->core.live_zero <= k)
5600 parent->core.live_zero = k + 1;
5605 panic("hammer2_base_insert: no room!");
5612 for (l = 0; l < count; ++l) {
5614 key_next = base[l].key +
5615 ((hammer2_key_t)1 << base[l].keybits) - 1;
5619 while (++l < count) {
5621 if (base[l].key <= key_next)
5622 panic("base_insert %d %d,%d,%d fail %p:%d", u, i, j, k, base, l);
5623 key_next = base[l].key +
5624 ((hammer2_key_t)1 << base[l].keybits) - 1;
5634 * Sort the blockref array for the chain. Used by the flush code to
5635 * sort the blockref[] array.
5637 * The chain must be exclusively locked AND spin-locked.
5639 typedef hammer2_blockref_t *hammer2_blockref_p;
5643 hammer2_base_sort_callback(const void *v1, const void *v2)
5645 hammer2_blockref_p bref1 = *(const hammer2_blockref_p *)v1;
5646 hammer2_blockref_p bref2 = *(const hammer2_blockref_p *)v2;
5649 * Make sure empty elements are placed at the end of the array
5651 if (bref1->type == 0) {
5652 if (bref2->type == 0)
5655 } else if (bref2->type == 0) {
5662 if (bref1->key < bref2->key)
5664 if (bref1->key > bref2->key)
5670 hammer2_base_sort(hammer2_chain_t *chain)
5672 hammer2_blockref_t *base;
5675 switch(chain->bref.type) {
5676 case HAMMER2_BREF_TYPE_INODE:
5678 * Special shortcut for embedded data returns the inode
5679 * itself. Callers must detect this condition and access
5680 * the embedded data (the strategy code does this for us).
5682 * This is only applicable to regular files and softlinks.
5684 if (chain->data->ipdata.meta.op_flags &
5685 HAMMER2_OPFLAG_DIRECTDATA) {
5688 base = &chain->data->ipdata.u.blockset.blockref[0];
5689 count = HAMMER2_SET_COUNT;
5691 case HAMMER2_BREF_TYPE_FREEMAP_NODE:
5692 case HAMMER2_BREF_TYPE_INDIRECT:
5694 * Optimize indirect blocks in the INITIAL state to avoid
5697 KKASSERT((chain->flags & HAMMER2_CHAIN_INITIAL) == 0);
5698 base = &chain->data->npdata[0];
5699 count = chain->bytes / sizeof(hammer2_blockref_t);
5701 case HAMMER2_BREF_TYPE_VOLUME:
5702 base = &chain->data->voldata.sroot_blockset.blockref[0];
5703 count = HAMMER2_SET_COUNT;
5705 case HAMMER2_BREF_TYPE_FREEMAP:
5706 base = &chain->data->blkset.blockref[0];
5707 count = HAMMER2_SET_COUNT;
5710 kprintf("hammer2_chain_lookup: unrecognized "
5711 "blockref(A) type: %d",
5714 tsleep(&base, 0, "dead", 0);
5715 panic("hammer2_chain_lookup: unrecognized "
5716 "blockref(A) type: %d",
5718 base = NULL; /* safety */
5719 count = 0; /* safety */
5721 kqsort(base, count, sizeof(*base), hammer2_base_sort_callback);
5727 * Chain memory management
5730 hammer2_chain_wait(hammer2_chain_t *chain)
5732 tsleep(chain, 0, "chnflw", 1);
5735 const hammer2_media_data_t *
5736 hammer2_chain_rdata(hammer2_chain_t *chain)
5738 KKASSERT(chain->data != NULL);
5739 return (chain->data);
5742 hammer2_media_data_t *
5743 hammer2_chain_wdata(hammer2_chain_t *chain)
5745 KKASSERT(chain->data != NULL);
5746 return (chain->data);
5750 * Set the check data for a chain. This can be a heavy-weight operation
5751 * and typically only runs on-flush. For file data check data is calculated
5752 * when the logical buffers are flushed.
5755 hammer2_chain_setcheck(hammer2_chain_t *chain, void *bdata)
5757 chain->bref.flags &= ~HAMMER2_BREF_FLAG_ZERO;
5759 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) {
5760 case HAMMER2_CHECK_NONE:
5762 case HAMMER2_CHECK_DISABLED:
5764 case HAMMER2_CHECK_ISCSI32:
5765 chain->bref.check.iscsi32.value =
5766 hammer2_icrc32(bdata, chain->bytes);
5768 case HAMMER2_CHECK_XXHASH64:
5769 chain->bref.check.xxhash64.value =
5770 XXH64(bdata, chain->bytes, XXH_HAMMER2_SEED);
5772 case HAMMER2_CHECK_SHA192:
5774 SHA256_CTX hash_ctx;
5776 uint8_t digest[SHA256_DIGEST_LENGTH];
5777 uint64_t digest64[SHA256_DIGEST_LENGTH/8];
5780 SHA256_Init(&hash_ctx);
5781 SHA256_Update(&hash_ctx, bdata, chain->bytes);
5782 SHA256_Final(u.digest, &hash_ctx);
5783 u.digest64[2] ^= u.digest64[3];
5785 chain->bref.check.sha192.data,
5786 sizeof(chain->bref.check.sha192.data));
5789 case HAMMER2_CHECK_FREEMAP:
5790 chain->bref.check.freemap.icrc32 =
5791 hammer2_icrc32(bdata, chain->bytes);
5794 kprintf("hammer2_chain_setcheck: unknown check type %02x\n",
5795 chain->bref.methods);
5801 hammer2_chain_testcheck(hammer2_chain_t *chain, void *bdata)
5807 if (chain->bref.flags & HAMMER2_BREF_FLAG_ZERO)
5810 switch(HAMMER2_DEC_CHECK(chain->bref.methods)) {
5811 case HAMMER2_CHECK_NONE:
5814 case HAMMER2_CHECK_DISABLED:
5817 case HAMMER2_CHECK_ISCSI32:
5818 check32 = hammer2_icrc32(bdata, chain->bytes);
5819 r = (chain->bref.check.iscsi32.value == check32);
5821 kprintf("chain %016jx.%02x meth=%02x CHECK FAIL "
5822 "(flags=%08x, bref/data %08x/%08x)\n",
5823 chain->bref.data_off,
5825 chain->bref.methods,
5827 chain->bref.check.iscsi32.value,
5830 hammer2_process_icrc32 += chain->bytes;
5832 case HAMMER2_CHECK_XXHASH64:
5833 check64 = XXH64(bdata, chain->bytes, XXH_HAMMER2_SEED);
5834 r = (chain->bref.check.xxhash64.value == check64);
5836 kprintf("chain %016jx.%02x key=%016jx "
5837 "meth=%02x CHECK FAIL "
5838 "(flags=%08x, bref/data %016jx/%016jx)\n",
5839 chain->bref.data_off,
5842 chain->bref.methods,
5844 chain->bref.check.xxhash64.value,
5847 hammer2_process_xxhash64 += chain->bytes;
5849 case HAMMER2_CHECK_SHA192:
5851 SHA256_CTX hash_ctx;
5853 uint8_t digest[SHA256_DIGEST_LENGTH];
5854 uint64_t digest64[SHA256_DIGEST_LENGTH/8];
5857 SHA256_Init(&hash_ctx);
5858 SHA256_Update(&hash_ctx, bdata, chain->bytes);
5859 SHA256_Final(u.digest, &hash_ctx);
5860 u.digest64[2] ^= u.digest64[3];
5862 chain->bref.check.sha192.data,
5863 sizeof(chain->bref.check.sha192.data)) == 0) {
5867 kprintf("chain %016jx.%02x meth=%02x "
5869 chain->bref.data_off,
5871 chain->bref.methods);
5875 case HAMMER2_CHECK_FREEMAP:
5876 r = (chain->bref.check.freemap.icrc32 ==
5877 hammer2_icrc32(bdata, chain->bytes));
5879 kprintf("chain %016jx.%02x meth=%02x "
5881 chain->bref.data_off,
5883 chain->bref.methods);
5884 kprintf("freemap.icrc %08x icrc32 %08x (%d)\n",
5885 chain->bref.check.freemap.icrc32,
5886 hammer2_icrc32(bdata, chain->bytes),
5889 kprintf("dio %p buf %016jx,%d bdata %p/%p\n",
5890 chain->dio, chain->dio->bp->b_loffset,
5891 chain->dio->bp->b_bufsize, bdata,
5892 chain->dio->bp->b_data);
5897 kprintf("hammer2_chain_setcheck: unknown check type %02x\n",
5898 chain->bref.methods);
5906 * Acquire the chain and parent representing the specified inode for the
5907 * device at the specified cluster index.
5909 * The flags passed in are LOOKUP flags, not RESOLVE flags.
5911 * If we are unable to locate the inode, HAMMER2_ERROR_EIO is returned and
5912 * *chainp will be NULL. *parentp may still be set error or not, or NULL
5913 * if the parent itself could not be resolved.
5915 * The caller may pass-in a locked *parentp and/or *chainp, or neither.
5916 * They will be unlocked and released by this function. The *parentp and
5917 * *chainp representing the located inode are returned locked.
5920 hammer2_chain_inode_find(hammer2_pfs_t *pmp, hammer2_key_t inum,
5921 int clindex, int flags,
5922 hammer2_chain_t **parentp, hammer2_chain_t **chainp)
5924 hammer2_chain_t *parent;
5925 hammer2_chain_t *rchain;
5926 hammer2_key_t key_dummy;
5927 hammer2_inode_t *ip;
5931 resolve_flags = (flags & HAMMER2_LOOKUP_SHARED) ?
5932 HAMMER2_RESOLVE_SHARED : 0;
5935 * Caller expects us to replace these.
5938 hammer2_chain_unlock(*chainp);
5939 hammer2_chain_drop(*chainp);
5943 hammer2_chain_unlock(*parentp);
5944 hammer2_chain_drop(*parentp);
5949 * Be very careful, this is a backend function and we CANNOT
5950 * lock any frontend inode structure we find. But we have to
5951 * look the inode up this way first in case it exists but is
5952 * detached from the radix tree.
5954 ip = hammer2_inode_lookup(pmp, inum);
5956 *chainp = hammer2_inode_chain_and_parent(ip, clindex,
5959 hammer2_inode_drop(ip);
5962 hammer2_chain_unlock(*chainp);
5963 hammer2_chain_drop(*chainp);
5966 hammer2_chain_unlock(*parentp);
5967 hammer2_chain_drop(*parentp);
5973 * Inodes hang off of the iroot (bit 63 is clear, differentiating
5974 * inodes from root directory entries in the key lookup).
5976 parent = hammer2_inode_chain(pmp->iroot, clindex, resolve_flags);
5979 rchain = hammer2_chain_lookup(&parent, &key_dummy,
5983 error = HAMMER2_ERROR_EIO;
5992 * Used by the bulkscan code to snapshot the synchronized storage for
5993 * a volume, allowing it to be scanned concurrently against normal
5997 hammer2_chain_bulksnap(hammer2_dev_t *hmp)
5999 hammer2_chain_t *copy;
6001 copy = hammer2_chain_alloc(hmp, hmp->spmp, &hmp->vchain.bref);
6002 copy->data = kmalloc(sizeof(copy->data->voldata),
6005 hammer2_voldata_lock(hmp);
6006 copy->data->voldata = hmp->volsync;
6007 hammer2_voldata_unlock(hmp);
6013 hammer2_chain_bulkdrop(hammer2_chain_t *copy)
6015 KKASSERT(copy->bref.type == HAMMER2_BREF_TYPE_VOLUME);
6016 KKASSERT(copy->data);
6017 kfree(copy->data, copy->hmp->mchain);
6019 atomic_add_long(&hammer2_chain_allocs, -1);
6020 hammer2_chain_drop(copy);
6024 * Returns non-zero if the chain (INODE or DIRENT) matches the
6028 hammer2_chain_dirent_test(hammer2_chain_t *chain, const char *name,
6031 const hammer2_inode_data_t *ripdata;
6032 const hammer2_dirent_head_t *den;
6034 if (chain->bref.type == HAMMER2_BREF_TYPE_INODE) {
6035 ripdata = &chain->data->ipdata;
6036 if (ripdata->meta.name_len == name_len &&
6037 bcmp(ripdata->filename, name, name_len) == 0) {
6041 if (chain->bref.type == HAMMER2_BREF_TYPE_DIRENT &&
6042 chain->bref.embed.dirent.namlen == name_len) {
6043 den = &chain->bref.embed.dirent;
6044 if (name_len > sizeof(chain->bref.check.buf) &&
6045 bcmp(chain->data->buf, name, name_len) == 0) {
6048 if (name_len <= sizeof(chain->bref.check.buf) &&
6049 bcmp(chain->bref.check.buf, name, name_len) == 0) {