22c22
< * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
---
> * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
118a119,122
> if (sm->sm_pp_root) {
> avl_remove(sm->sm_pp_root, ss_before);
> avl_remove(sm->sm_pp_root, ss_after);
> }
120a125
> ss = ss_after;
122a128,130
> if (sm->sm_pp_root)
> avl_remove(sm->sm_pp_root, ss_before);
> ss = ss_before;
124a133,135
> if (sm->sm_pp_root)
> avl_remove(sm->sm_pp_root, ss_after);
> ss = ss_after;
131a143,145
> if (sm->sm_pp_root)
> avl_add(sm->sm_pp_root, ss);
>
165a180,182
> if (sm->sm_pp_root)
> avl_remove(sm->sm_pp_root, ss);
>
171a189,190
> if (sm->sm_pp_root)
> avl_add(sm->sm_pp_root, newseg);
178a198
> ss = NULL;
180a201,203
> if (sm->sm_pp_root && ss != NULL)
> avl_add(sm->sm_pp_root, ss);
>
184c207
< int
---
> boolean_t
223a247,248
> ASSERT(MUTEX_HELD(sm->sm_lock));
>
228,257d252
< void
< space_map_excise(space_map_t *sm, uint64_t start, uint64_t size)
< {
< avl_tree_t *t = &sm->sm_root;
< avl_index_t where;
< space_seg_t *ss, search;
< uint64_t end = start + size;
< uint64_t rm_start, rm_end;
<
< ASSERT(MUTEX_HELD(sm->sm_lock));
<
< search.ss_start = start;
< search.ss_end = start;
<
< for (;;) {
< ss = avl_find(t, &search, &where);
<
< if (ss == NULL)
< ss = avl_nearest(t, where, AVL_AFTER);
<
< if (ss == NULL || ss->ss_start >= end)
< break;
<
< rm_start = MAX(ss->ss_start, start);
< rm_end = MIN(ss->ss_end, end);
<
< space_map_remove(sm, rm_start, rm_end - rm_start);
< }
< }
<
259,279d253
< * Replace smd with the union of smd and sms.
< */
< void
< space_map_union(space_map_t *smd, space_map_t *sms)
< {
< avl_tree_t *t = &sms->sm_root;
< space_seg_t *ss;
<
< ASSERT(MUTEX_HELD(smd->sm_lock));
<
< /*
< * For each source segment, remove any intersections with the
< * destination, then add the source segment to the destination.
< */
< for (ss = avl_first(t); ss != NULL; ss = AVL_NEXT(t, ss)) {
< space_map_excise(smd, ss->ss_start, ss->ss_end - ss->ss_start);
< space_map_add(smd, ss->ss_start, ss->ss_end - ss->ss_start);
< }
< }
<
< /*
340c314,315
< error = dmu_read(os, smo->smo_object, offset, size, entry_map);
---
> error = dmu_read(os, smo->smo_object, offset, size, entry_map,
> DMU_READ_PREFETCH);
393a369,377
> space_map_maxsize(space_map_t *sm)
> {
> if (sm->sm_loaded && sm->sm_ops != NULL)
> return (sm->sm_ops->smop_max(sm));
> else
> return (-1ULL);
> }
>
> uint64_t
507a492,619
>
> /*
> * Space map reference trees.
> *
> * A space map is a collection of integers. Every integer is either
> * in the map, or it's not. A space map reference tree generalizes
> * the idea: it allows its members to have arbitrary reference counts,
> * as opposed to the implicit reference count of 0 or 1 in a space map.
> * This representation comes in handy when computing the union or
> * intersection of multiple space maps. For example, the union of
> * N space maps is the subset of the reference tree with refcnt >= 1.
> * The intersection of N space maps is the subset with refcnt >= N.
> *
> * [It's very much like a Fourier transform. Unions and intersections
> * are hard to perform in the 'space map domain', so we convert the maps
> * into the 'reference count domain', where it's trivial, then invert.]
> *
> * vdev_dtl_reassess() uses computations of this form to determine
> * DTL_MISSING and DTL_OUTAGE for interior vdevs -- e.g. a RAID-Z vdev
> * has an outage wherever refcnt >= vdev_nparity + 1, and a mirror vdev
> * has an outage wherever refcnt >= vdev_children.
> */
> static int
> space_map_ref_compare(const void *x1, const void *x2)
> {
> const space_ref_t *sr1 = x1;
> const space_ref_t *sr2 = x2;
>
> if (sr1->sr_offset < sr2->sr_offset)
> return (-1);
> if (sr1->sr_offset > sr2->sr_offset)
> return (1);
>
> if (sr1 < sr2)
> return (-1);
> if (sr1 > sr2)
> return (1);
>
> return (0);
> }
>
> void
> space_map_ref_create(avl_tree_t *t)
> {
> avl_create(t, space_map_ref_compare,
> sizeof (space_ref_t), offsetof(space_ref_t, sr_node));
> }
>
> void
> space_map_ref_destroy(avl_tree_t *t)
> {
> space_ref_t *sr;
> void *cookie = NULL;
>
> while ((sr = avl_destroy_nodes(t, &cookie)) != NULL)
> kmem_free(sr, sizeof (*sr));
>
> avl_destroy(t);
> }
>
> static void
> space_map_ref_add_node(avl_tree_t *t, uint64_t offset, int64_t refcnt)
> {
> space_ref_t *sr;
>
> sr = kmem_alloc(sizeof (*sr), KM_SLEEP);
> sr->sr_offset = offset;
> sr->sr_refcnt = refcnt;
>
> avl_add(t, sr);
> }
>
> void
> space_map_ref_add_seg(avl_tree_t *t, uint64_t start, uint64_t end,
> int64_t refcnt)
> {
> space_map_ref_add_node(t, start, refcnt);
> space_map_ref_add_node(t, end, -refcnt);
> }
>
> /*
> * Convert (or add) a space map into a reference tree.
> */
> void
> space_map_ref_add_map(avl_tree_t *t, space_map_t *sm, int64_t refcnt)
> {
> space_seg_t *ss;
>
> ASSERT(MUTEX_HELD(sm->sm_lock));
>
> for (ss = avl_first(&sm->sm_root); ss; ss = AVL_NEXT(&sm->sm_root, ss))
> space_map_ref_add_seg(t, ss->ss_start, ss->ss_end, refcnt);
> }
>
> /*
> * Convert a reference tree into a space map. The space map will contain
> * all members of the reference tree for which refcnt >= minref.
> */
> void
> space_map_ref_generate_map(avl_tree_t *t, space_map_t *sm, int64_t minref)
> {
> uint64_t start = -1ULL;
> int64_t refcnt = 0;
> space_ref_t *sr;
>
> ASSERT(MUTEX_HELD(sm->sm_lock));
>
> space_map_vacate(sm, NULL, NULL);
>
> for (sr = avl_first(t); sr != NULL; sr = AVL_NEXT(t, sr)) {
> refcnt += sr->sr_refcnt;
> if (refcnt >= minref) {
> if (start == -1ULL) {
> start = sr->sr_offset;
> }
> } else {
> if (start != -1ULL) {
> uint64_t end = sr->sr_offset;
> ASSERT(start <= end);
> if (end > start)
> space_map_add(sm, start, end - start);
> start = -1ULL;
> }
> }
> }
> ASSERT(refcnt == 0);
> ASSERT(start == -1ULL);
> }