* Use is subject to license terms.
*/
/*
- * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
#include <sys/dmu.h>
+#include <sys/dmu_tx.h>
+#include <sys/dnode.h>
+#include <sys/dsl_pool.h>
#include <sys/zio.h>
#include <sys/space_map.h>
-
-static kmem_cache_t *space_seg_cache;
-
-void
-space_map_init(void)
-{
- ASSERT(space_seg_cache == NULL);
- space_seg_cache = kmem_cache_create("space_seg_cache",
- sizeof (space_seg_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
-}
-
-void
-space_map_fini(void)
-{
- kmem_cache_destroy(space_seg_cache);
- space_seg_cache = NULL;
-}
-
-/*
- * Space map routines.
- * NOTE: caller is responsible for all locking.
- */
-static int
-space_map_seg_compare(const void *x1, const void *x2)
-{
- const space_seg_t *s1 = x1;
- const space_seg_t *s2 = x2;
-
- if (s1->ss_start < s2->ss_start) {
- if (s1->ss_end > s2->ss_start)
- return (0);
- return (-1);
- }
- if (s1->ss_start > s2->ss_start) {
- if (s1->ss_start < s2->ss_end)
- return (0);
- return (1);
- }
- return (0);
-}
-
-void
-space_map_create(space_map_t *sm, uint64_t start, uint64_t size, uint8_t shift,
- kmutex_t *lp)
-{
- bzero(sm, sizeof (*sm));
-
- cv_init(&sm->sm_load_cv, NULL, CV_DEFAULT, NULL);
-
- avl_create(&sm->sm_root, space_map_seg_compare,
- sizeof (space_seg_t), offsetof(struct space_seg, ss_node));
-
- sm->sm_start = start;
- sm->sm_size = size;
- sm->sm_shift = shift;
- sm->sm_lock = lp;
-}
-
-void
-space_map_destroy(space_map_t *sm)
-{
- ASSERT(!sm->sm_loaded && !sm->sm_loading);
- VERIFY0(sm->sm_space);
- avl_destroy(&sm->sm_root);
- cv_destroy(&sm->sm_load_cv);
-}
-
-void
-space_map_add(space_map_t *sm, uint64_t start, uint64_t size)
-{
- avl_index_t where;
- space_seg_t *ss_before, *ss_after, *ss;
- uint64_t end = start + size;
- int merge_before, merge_after;
-
- ASSERT(MUTEX_HELD(sm->sm_lock));
- VERIFY(!sm->sm_condensing);
- VERIFY(size != 0);
- VERIFY3U(start, >=, sm->sm_start);
- VERIFY3U(end, <=, sm->sm_start + sm->sm_size);
- VERIFY(sm->sm_space + size <= sm->sm_size);
- VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0);
- VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0);
-
- ss = space_map_find(sm, start, size, &where);
- if (ss != NULL) {
- zfs_panic_recover("zfs: allocating allocated segment"
- "(offset=%llu size=%llu)\n",
- (longlong_t)start, (longlong_t)size);
- return;
- }
-
- /* Make sure we don't overlap with either of our neighbors */
- VERIFY(ss == NULL);
-
- ss_before = avl_nearest(&sm->sm_root, where, AVL_BEFORE);
- ss_after = avl_nearest(&sm->sm_root, where, AVL_AFTER);
-
- merge_before = (ss_before != NULL && ss_before->ss_end == start);
- merge_after = (ss_after != NULL && ss_after->ss_start == end);
-
- if (merge_before && merge_after) {
- avl_remove(&sm->sm_root, ss_before);
- if (sm->sm_pp_root) {
- avl_remove(sm->sm_pp_root, ss_before);
- avl_remove(sm->sm_pp_root, ss_after);
- }
- ss_after->ss_start = ss_before->ss_start;
- kmem_cache_free(space_seg_cache, ss_before);
- ss = ss_after;
- } else if (merge_before) {
- ss_before->ss_end = end;
- if (sm->sm_pp_root)
- avl_remove(sm->sm_pp_root, ss_before);
- ss = ss_before;
- } else if (merge_after) {
- ss_after->ss_start = start;
- if (sm->sm_pp_root)
- avl_remove(sm->sm_pp_root, ss_after);
- ss = ss_after;
- } else {
- ss = kmem_cache_alloc(space_seg_cache, KM_PUSHPAGE);
- ss->ss_start = start;
- ss->ss_end = end;
- avl_insert(&sm->sm_root, ss, where);
- }
-
- if (sm->sm_pp_root)
- avl_add(sm->sm_pp_root, ss);
-
- sm->sm_space += size;
-}
-
-void
-space_map_remove(space_map_t *sm, uint64_t start, uint64_t size)
-{
- avl_index_t where;
- space_seg_t *ss, *newseg;
- uint64_t end = start + size;
- int left_over, right_over;
-
- VERIFY(!sm->sm_condensing);
- ss = space_map_find(sm, start, size, &where);
-
- /* Make sure we completely overlap with someone */
- if (ss == NULL) {
- zfs_panic_recover("zfs: freeing free segment "
- "(offset=%llu size=%llu)",
- (longlong_t)start, (longlong_t)size);
- return;
- }
- VERIFY3U(ss->ss_start, <=, start);
- VERIFY3U(ss->ss_end, >=, end);
- VERIFY(sm->sm_space - size <= sm->sm_size);
-
- left_over = (ss->ss_start != start);
- right_over = (ss->ss_end != end);
-
- if (sm->sm_pp_root)
- avl_remove(sm->sm_pp_root, ss);
-
- if (left_over && right_over) {
- newseg = kmem_cache_alloc(space_seg_cache, KM_PUSHPAGE);
- newseg->ss_start = end;
- newseg->ss_end = ss->ss_end;
- ss->ss_end = start;
- avl_insert_here(&sm->sm_root, newseg, ss, AVL_AFTER);
- if (sm->sm_pp_root)
- avl_add(sm->sm_pp_root, newseg);
- } else if (left_over) {
- ss->ss_end = start;
- } else if (right_over) {
- ss->ss_start = end;
- } else {
- avl_remove(&sm->sm_root, ss);
- kmem_cache_free(space_seg_cache, ss);
- ss = NULL;
- }
-
- if (sm->sm_pp_root && ss != NULL)
- avl_add(sm->sm_pp_root, ss);
-
- sm->sm_space -= size;
-}
-
-space_seg_t *
-space_map_find(space_map_t *sm, uint64_t start, uint64_t size,
- avl_index_t *wherep)
-{
- space_seg_t ssearch, *ss;
-
- ASSERT(MUTEX_HELD(sm->sm_lock));
- VERIFY(size != 0);
- VERIFY(P2PHASE(start, 1ULL << sm->sm_shift) == 0);
- VERIFY(P2PHASE(size, 1ULL << sm->sm_shift) == 0);
-
- ssearch.ss_start = start;
- ssearch.ss_end = start + size;
- ss = avl_find(&sm->sm_root, &ssearch, wherep);
-
- if (ss != NULL && ss->ss_start <= start && ss->ss_end >= start + size)
- return (ss);
- return (NULL);
-}
-
-boolean_t
-space_map_contains(space_map_t *sm, uint64_t start, uint64_t size)
-{
- avl_index_t where;
-
- return (space_map_find(sm, start, size, &where) != 0);
-}
-
-void
-space_map_swap(space_map_t **msrc, space_map_t **mdst)
-{
- space_map_t *sm;
-
- ASSERT(MUTEX_HELD((*msrc)->sm_lock));
- ASSERT0((*mdst)->sm_space);
- ASSERT0(avl_numnodes(&(*mdst)->sm_root));
-
- sm = *msrc;
- *msrc = *mdst;
- *mdst = sm;
-}
-
-void
-space_map_vacate(space_map_t *sm, space_map_func_t *func, space_map_t *mdest)
-{
- space_seg_t *ss;
- void *cookie = NULL;
-
- ASSERT(MUTEX_HELD(sm->sm_lock));
-
- while ((ss = avl_destroy_nodes(&sm->sm_root, &cookie)) != NULL) {
- if (func != NULL)
- func(mdest, ss->ss_start, ss->ss_end - ss->ss_start);
- kmem_cache_free(space_seg_cache, ss);
- }
- sm->sm_space = 0;
-}
-
-void
-space_map_walk(space_map_t *sm, space_map_func_t *func, space_map_t *mdest)
-{
- 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))
- func(mdest, ss->ss_start, ss->ss_end - ss->ss_start);
-}
+#include <sys/refcount.h>
+#include <sys/zfeature.h>
/*
- * Wait for any in-progress space_map_load() to complete.
+ * The data for a given space map can be kept on blocks of any size.
+ * Larger blocks entail fewer i/o operations, but they also cause the
+ * DMU to keep more data in-core, and also to waste more i/o bandwidth
+ * when only a few blocks have changed since the last transaction group.
*/
-void
-space_map_load_wait(space_map_t *sm)
-{
- ASSERT(MUTEX_HELD(sm->sm_lock));
-
- while (sm->sm_loading) {
- ASSERT(!sm->sm_loaded);
- cv_wait(&sm->sm_load_cv, sm->sm_lock);
- }
-}
+int space_map_blksz = (1 << 12);
/*
+ * Load the space map disk into the specified range tree. Segments of maptype
+ * are added to the range tree, other segment types are removed.
+ *
* Note: space_map_load() will drop sm_lock across dmu_read() calls.
* The caller must be OK with this.
*/
int
-space_map_load(space_map_t *sm, space_map_ops_t *ops, uint8_t maptype,
- space_map_obj_t *smo, objset_t *os)
+space_map_load(space_map_t *sm, range_tree_t *rt, maptype_t maptype)
{
uint64_t *entry, *entry_map, *entry_map_end;
uint64_t bufsize, size, offset, end, space;
- uint64_t mapstart = sm->sm_start;
int error = 0;
ASSERT(MUTEX_HELD(sm->sm_lock));
- ASSERT(!sm->sm_loaded);
- ASSERT(!sm->sm_loading);
- sm->sm_loading = B_TRUE;
- end = smo->smo_objsize;
- space = smo->smo_alloc;
+ end = space_map_length(sm);
+ space = space_map_allocated(sm);
- ASSERT(sm->sm_ops == NULL);
- VERIFY0(sm->sm_space);
+ VERIFY0(range_tree_space(rt));
if (maptype == SM_FREE) {
- space_map_add(sm, sm->sm_start, sm->sm_size);
+ range_tree_add(rt, sm->sm_start, sm->sm_size);
space = sm->sm_size - space;
}
- bufsize = 1ULL << SPACE_MAP_BLOCKSHIFT;
+ bufsize = MAX(sm->sm_blksz, SPA_MINBLOCKSIZE);
entry_map = zio_buf_alloc(bufsize);
mutex_exit(sm->sm_lock);
- if (end > bufsize)
- dmu_prefetch(os, smo->smo_object, bufsize, end - bufsize);
+ if (end > bufsize) {
+ dmu_prefetch(sm->sm_os, space_map_object(sm), bufsize,
+ end - bufsize);
+ }
mutex_enter(sm->sm_lock);
for (offset = 0; offset < end; offset += bufsize) {
size = MIN(end - offset, bufsize);
VERIFY(P2PHASE(size, sizeof (uint64_t)) == 0);
VERIFY(size != 0);
+ ASSERT3U(sm->sm_blksz, !=, 0);
dprintf("object=%llu offset=%llx size=%llx\n",
- smo->smo_object, offset, size);
+ space_map_object(sm), offset, size);
mutex_exit(sm->sm_lock);
- error = dmu_read(os, smo->smo_object, offset, size, entry_map,
- DMU_READ_PREFETCH);
+ error = dmu_read(sm->sm_os, space_map_object(sm), offset, size,
+ entry_map, DMU_READ_PREFETCH);
mutex_enter(sm->sm_lock);
if (error != 0)
break;
entry_map_end = entry_map + (size / sizeof (uint64_t));
for (entry = entry_map; entry < entry_map_end; entry++) {
uint64_t e = *entry;
+ uint64_t offset, size;
if (SM_DEBUG_DECODE(e)) /* Skip debug entries */
continue;
- (SM_TYPE_DECODE(e) == maptype ?
- space_map_add : space_map_remove)(sm,
- (SM_OFFSET_DECODE(e) << sm->sm_shift) + mapstart,
- SM_RUN_DECODE(e) << sm->sm_shift);
+ offset = (SM_OFFSET_DECODE(e) << sm->sm_shift) +
+ sm->sm_start;
+ size = SM_RUN_DECODE(e) << sm->sm_shift;
+
+ VERIFY0(P2PHASE(offset, 1ULL << sm->sm_shift));
+ VERIFY0(P2PHASE(size, 1ULL << sm->sm_shift));
+ VERIFY3U(offset, >=, sm->sm_start);
+ VERIFY3U(offset + size, <=, sm->sm_start + sm->sm_size);
+ if (SM_TYPE_DECODE(e) == maptype) {
+ VERIFY3U(range_tree_space(rt) + size, <=,
+ sm->sm_size);
+ range_tree_add(rt, offset, size);
+ } else {
+ range_tree_remove(rt, offset, size);
+ }
}
}
- if (error == 0) {
- VERIFY3U(sm->sm_space, ==, space);
-
- sm->sm_loaded = B_TRUE;
- sm->sm_ops = ops;
- if (ops != NULL)
- ops->smop_load(sm);
- } else {
- space_map_vacate(sm, NULL, NULL);
- }
+ if (error == 0)
+ VERIFY3U(range_tree_space(rt), ==, space);
+ else
+ range_tree_vacate(rt, NULL, NULL);
zio_buf_free(entry_map, bufsize);
-
- sm->sm_loading = B_FALSE;
-
- cv_broadcast(&sm->sm_load_cv);
-
return (error);
}
void
-space_map_unload(space_map_t *sm)
+space_map_histogram_clear(space_map_t *sm)
{
- ASSERT(MUTEX_HELD(sm->sm_lock));
-
- if (sm->sm_loaded && sm->sm_ops != NULL)
- sm->sm_ops->smop_unload(sm);
-
- sm->sm_loaded = B_FALSE;
- sm->sm_ops = NULL;
-
- space_map_vacate(sm, NULL, NULL);
-}
+ if (sm->sm_dbuf->db_size != sizeof (space_map_phys_t))
+ return;
-uint64_t
-space_map_maxsize(space_map_t *sm)
-{
- ASSERT(sm->sm_ops != NULL);
- return (sm->sm_ops->smop_max(sm));
+ bzero(sm->sm_phys->smp_histogram, sizeof (sm->sm_phys->smp_histogram));
}
-uint64_t
-space_map_alloc(space_map_t *sm, uint64_t size)
+boolean_t
+space_map_histogram_verify(space_map_t *sm, range_tree_t *rt)
{
- uint64_t start;
+ int i;
- start = sm->sm_ops->smop_alloc(sm, size);
- if (start != -1ULL)
- space_map_remove(sm, start, size);
- return (start);
+ /*
+ * Verify that the in-core range tree does not have any
+ * ranges smaller than our sm_shift size.
+ */
+ for (i = 0; i < sm->sm_shift; i++) {
+ if (rt->rt_histogram[i] != 0)
+ return (B_FALSE);
+ }
+ return (B_TRUE);
}
void
-space_map_claim(space_map_t *sm, uint64_t start, uint64_t size)
+space_map_histogram_add(space_map_t *sm, range_tree_t *rt, dmu_tx_t *tx)
{
- sm->sm_ops->smop_claim(sm, start, size);
- space_map_remove(sm, start, size);
+ int idx = 0;
+ int i;
+
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ ASSERT(dmu_tx_is_syncing(tx));
+ VERIFY3U(space_map_object(sm), !=, 0);
+
+ if (sm->sm_dbuf->db_size != sizeof (space_map_phys_t))
+ return;
+
+ dmu_buf_will_dirty(sm->sm_dbuf, tx);
+
+ ASSERT(space_map_histogram_verify(sm, rt));
+
+ /*
+ * Transfer the content of the range tree histogram to the space
+ * map histogram. The space map histogram contains 32 buckets ranging
+ * between 2^sm_shift to 2^(32+sm_shift-1). The range tree,
+ * however, can represent ranges from 2^0 to 2^63. Since the space
+ * map only cares about allocatable blocks (minimum of sm_shift) we
+ * can safely ignore all ranges in the range tree smaller than sm_shift.
+ */
+ for (i = sm->sm_shift; i < RANGE_TREE_HISTOGRAM_SIZE; i++) {
+
+ /*
+ * Since the largest histogram bucket in the space map is
+ * 2^(32+sm_shift-1), we need to normalize the values in
+ * the range tree for any bucket larger than that size. For
+ * example given an sm_shift of 9, ranges larger than 2^40
+ * would get normalized as if they were 1TB ranges. Assume
+ * the range tree had a count of 5 in the 2^44 (16TB) bucket,
+ * the calculation below would normalize this to 5 * 2^4 (16).
+ */
+ ASSERT3U(i, >=, idx + sm->sm_shift);
+ sm->sm_phys->smp_histogram[idx] +=
+ rt->rt_histogram[i] << (i - idx - sm->sm_shift);
+
+ /*
+ * Increment the space map's index as long as we haven't
+ * reached the maximum bucket size. Accumulate all ranges
+ * larger than the max bucket size into the last bucket.
+ */
+ if (idx < SPACE_MAP_HISTOGRAM_SIZE - 1) {
+ ASSERT3U(idx + sm->sm_shift, ==, i);
+ idx++;
+ ASSERT3U(idx, <, SPACE_MAP_HISTOGRAM_SIZE);
+ }
+ }
}
-void
-space_map_free(space_map_t *sm, uint64_t start, uint64_t size)
+uint64_t
+space_map_entries(space_map_t *sm, range_tree_t *rt)
{
- space_map_add(sm, start, size);
- sm->sm_ops->smop_free(sm, start, size);
+ avl_tree_t *t = &rt->rt_root;
+ range_seg_t *rs;
+ uint64_t size, entries;
+
+ /*
+ * All space_maps always have a debug entry so account for it here.
+ */
+ entries = 1;
+
+ /*
+ * Traverse the range tree and calculate the number of space map
+ * entries that would be required to write out the range tree.
+ */
+ for (rs = avl_first(t); rs != NULL; rs = AVL_NEXT(t, rs)) {
+ size = (rs->rs_end - rs->rs_start) >> sm->sm_shift;
+ entries += howmany(size, SM_RUN_MAX);
+ }
+ return (entries);
}
/*
- * Note: space_map_sync() will drop sm_lock across dmu_write() calls.
+ * Note: space_map_write() will drop sm_lock across dmu_write() calls.
*/
void
-space_map_sync(space_map_t *sm, uint8_t maptype,
- space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx)
+space_map_write(space_map_t *sm, range_tree_t *rt, maptype_t maptype,
+ dmu_tx_t *tx)
{
+ objset_t *os = sm->sm_os;
spa_t *spa = dmu_objset_spa(os);
- avl_tree_t *t = &sm->sm_root;
- space_seg_t *ss;
- uint64_t bufsize, start, size, run_len, total, sm_space, nodes;
+ avl_tree_t *t = &rt->rt_root;
+ range_seg_t *rs;
+ uint64_t size, total, rt_space, nodes;
uint64_t *entry, *entry_map, *entry_map_end;
+ uint64_t expected_entries, actual_entries = 1;
- ASSERT(MUTEX_HELD(sm->sm_lock));
+ ASSERT(MUTEX_HELD(rt->rt_lock));
+ ASSERT(dsl_pool_sync_context(dmu_objset_pool(os)));
+ VERIFY3U(space_map_object(sm), !=, 0);
+ dmu_buf_will_dirty(sm->sm_dbuf, tx);
- if (sm->sm_space == 0)
- return;
+ /*
+ * This field is no longer necessary since the in-core space map
+ * now contains the object number but is maintained for backwards
+ * compatibility.
+ */
+ sm->sm_phys->smp_object = sm->sm_object;
- dprintf("object %4llu, txg %llu, pass %d, %c, count %lu, space %llx\n",
- smo->smo_object, dmu_tx_get_txg(tx), spa_sync_pass(spa),
- maptype == SM_ALLOC ? 'A' : 'F', avl_numnodes(&sm->sm_root),
- sm->sm_space);
+ if (range_tree_space(rt) == 0) {
+ VERIFY3U(sm->sm_object, ==, sm->sm_phys->smp_object);
+ return;
+ }
if (maptype == SM_ALLOC)
- smo->smo_alloc += sm->sm_space;
+ sm->sm_phys->smp_alloc += range_tree_space(rt);
else
- smo->smo_alloc -= sm->sm_space;
+ sm->sm_phys->smp_alloc -= range_tree_space(rt);
- bufsize = (8 + avl_numnodes(&sm->sm_root)) * sizeof (uint64_t);
- bufsize = MIN(bufsize, 1ULL << SPACE_MAP_BLOCKSHIFT);
- entry_map = zio_buf_alloc(bufsize);
- entry_map_end = entry_map + (bufsize / sizeof (uint64_t));
+ expected_entries = space_map_entries(sm, rt);
+
+ entry_map = zio_buf_alloc(sm->sm_blksz);
+ entry_map_end = entry_map + (sm->sm_blksz / sizeof (uint64_t));
entry = entry_map;
*entry++ = SM_DEBUG_ENCODE(1) |
SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx));
total = 0;
- nodes = avl_numnodes(&sm->sm_root);
- sm_space = sm->sm_space;
- for (ss = avl_first(t); ss != NULL; ss = AVL_NEXT(t, ss)) {
- size = ss->ss_end - ss->ss_start;
- start = (ss->ss_start - sm->sm_start) >> sm->sm_shift;
+ nodes = avl_numnodes(&rt->rt_root);
+ rt_space = range_tree_space(rt);
+ for (rs = avl_first(t); rs != NULL; rs = AVL_NEXT(t, rs)) {
+ uint64_t start;
+
+ size = (rs->rs_end - rs->rs_start) >> sm->sm_shift;
+ start = (rs->rs_start - sm->sm_start) >> sm->sm_shift;
- total += size;
- size >>= sm->sm_shift;
+ total += size << sm->sm_shift;
+
+ while (size != 0) {
+ uint64_t run_len;
- while (size) {
run_len = MIN(size, SM_RUN_MAX);
if (entry == entry_map_end) {
- mutex_exit(sm->sm_lock);
- dmu_write(os, smo->smo_object, smo->smo_objsize,
- bufsize, entry_map, tx);
- mutex_enter(sm->sm_lock);
- smo->smo_objsize += bufsize;
+ mutex_exit(rt->rt_lock);
+ dmu_write(os, space_map_object(sm),
+ sm->sm_phys->smp_objsize, sm->sm_blksz,
+ entry_map, tx);
+ mutex_enter(rt->rt_lock);
+ sm->sm_phys->smp_objsize += sm->sm_blksz;
entry = entry_map;
}
start += run_len;
size -= run_len;
+ actual_entries++;
}
}
if (entry != entry_map) {
size = (entry - entry_map) * sizeof (uint64_t);
- mutex_exit(sm->sm_lock);
- dmu_write(os, smo->smo_object, smo->smo_objsize,
+ mutex_exit(rt->rt_lock);
+ dmu_write(os, space_map_object(sm), sm->sm_phys->smp_objsize,
size, entry_map, tx);
- mutex_enter(sm->sm_lock);
- smo->smo_objsize += size;
+ mutex_enter(rt->rt_lock);
+ sm->sm_phys->smp_objsize += size;
}
+ ASSERT3U(expected_entries, ==, actual_entries);
/*
* Ensure that the space_map's accounting wasn't changed
* while we were in the middle of writing it out.
*/
- VERIFY3U(nodes, ==, avl_numnodes(&sm->sm_root));
- VERIFY3U(sm->sm_space, ==, sm_space);
- VERIFY3U(sm->sm_space, ==, total);
+ VERIFY3U(nodes, ==, avl_numnodes(&rt->rt_root));
+ VERIFY3U(range_tree_space(rt), ==, rt_space);
+ VERIFY3U(range_tree_space(rt), ==, total);
- zio_buf_free(entry_map, bufsize);
+ zio_buf_free(entry_map, sm->sm_blksz);
}
-void
-space_map_truncate(space_map_obj_t *smo, objset_t *os, dmu_tx_t *tx)
+static int
+space_map_open_impl(space_map_t *sm)
{
- VERIFY(dmu_free_range(os, smo->smo_object, 0, -1ULL, tx) == 0);
+ int error;
+ u_longlong_t blocks;
+
+ error = dmu_bonus_hold(sm->sm_os, sm->sm_object, sm, &sm->sm_dbuf);
+ if (error)
+ return (error);
- smo->smo_objsize = 0;
- smo->smo_alloc = 0;
+ dmu_object_size_from_db(sm->sm_dbuf, &sm->sm_blksz, &blocks);
+ sm->sm_phys = sm->sm_dbuf->db_data;
+ return (0);
}
-/*
- * 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)
+int
+space_map_open(space_map_t **smp, objset_t *os, uint64_t object,
+ uint64_t start, uint64_t size, uint8_t shift, kmutex_t *lp)
{
- const space_ref_t *sr1 = x1;
- const space_ref_t *sr2 = x2;
+ space_map_t *sm;
+ int error;
- if (sr1->sr_offset < sr2->sr_offset)
- return (-1);
- if (sr1->sr_offset > sr2->sr_offset)
- return (1);
+ ASSERT(*smp == NULL);
+ ASSERT(os != NULL);
+ ASSERT(object != 0);
- if (sr1 < sr2)
- return (-1);
- if (sr1 > sr2)
- return (1);
+ sm = kmem_alloc(sizeof (space_map_t), KM_SLEEP);
+
+ sm->sm_start = start;
+ sm->sm_size = size;
+ sm->sm_shift = shift;
+ sm->sm_lock = lp;
+ sm->sm_os = os;
+ sm->sm_object = object;
+ sm->sm_length = 0;
+ sm->sm_alloc = 0;
+ sm->sm_blksz = 0;
+ sm->sm_dbuf = NULL;
+ sm->sm_phys = NULL;
+
+ error = space_map_open_impl(sm);
+ if (error != 0) {
+ space_map_close(sm);
+ return (error);
+ }
+
+ *smp = sm;
return (0);
}
void
-space_map_ref_create(avl_tree_t *t)
+space_map_close(space_map_t *sm)
{
- avl_create(t, space_map_ref_compare,
- sizeof (space_ref_t), offsetof(space_ref_t, sr_node));
+ if (sm == NULL)
+ return;
+
+ if (sm->sm_dbuf != NULL)
+ dmu_buf_rele(sm->sm_dbuf, sm);
+ sm->sm_dbuf = NULL;
+ sm->sm_phys = NULL;
+
+ kmem_free(sm, sizeof (*sm));
}
void
-space_map_ref_destroy(avl_tree_t *t)
+space_map_truncate(space_map_t *sm, dmu_tx_t *tx)
{
- space_ref_t *sr;
- void *cookie = NULL;
+ objset_t *os = sm->sm_os;
+ spa_t *spa = dmu_objset_spa(os);
+ dmu_object_info_t doi;
+
+ ASSERT(dsl_pool_sync_context(dmu_objset_pool(os)));
+ ASSERT(dmu_tx_is_syncing(tx));
- while ((sr = avl_destroy_nodes(t, &cookie)) != NULL)
- kmem_free(sr, sizeof (*sr));
+ dmu_object_info_from_db(sm->sm_dbuf, &doi);
+
+ /*
+ * If the space map has the wrong bonus size (because
+ * SPA_FEATURE_SPACEMAP_HISTOGRAM has recently been enabled), or
+ * the wrong block size (because space_map_blksz has changed),
+ * free and re-allocate its object with the updated sizes.
+ *
+ * Otherwise, just truncate the current object.
+ */
+ if ((spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM) &&
+ doi.doi_bonus_size != sizeof (space_map_phys_t)) ||
+ doi.doi_data_block_size != space_map_blksz) {
+ zfs_dbgmsg("txg %llu, spa %s, reallocating: "
+ "old bonus %llu, old blocksz %u", dmu_tx_get_txg(tx),
+ spa_name(spa), doi.doi_bonus_size, doi.doi_data_block_size);
+
+ space_map_free(sm, tx);
+ dmu_buf_rele(sm->sm_dbuf, sm);
+
+ sm->sm_object = space_map_alloc(sm->sm_os, tx);
+ VERIFY0(space_map_open_impl(sm));
+ } else {
+ VERIFY0(dmu_free_range(os, space_map_object(sm), 0, -1ULL, tx));
+
+ /*
+ * If the spacemap is reallocated, its histogram
+ * will be reset. Do the same in the common case so that
+ * bugs related to the uncommon case do not go unnoticed.
+ */
+ bzero(sm->sm_phys->smp_histogram,
+ sizeof (sm->sm_phys->smp_histogram));
+ }
- avl_destroy(t);
+ dmu_buf_will_dirty(sm->sm_dbuf, tx);
+ sm->sm_phys->smp_objsize = 0;
+ sm->sm_phys->smp_alloc = 0;
}
-static void
-space_map_ref_add_node(avl_tree_t *t, uint64_t offset, int64_t refcnt)
+/*
+ * Update the in-core space_map allocation and length values.
+ */
+void
+space_map_update(space_map_t *sm)
{
- space_ref_t *sr;
+ if (sm == NULL)
+ return;
- sr = kmem_alloc(sizeof (*sr), KM_PUSHPAGE);
- sr->sr_offset = offset;
- sr->sr_refcnt = refcnt;
+ ASSERT(MUTEX_HELD(sm->sm_lock));
- avl_add(t, sr);
+ sm->sm_alloc = sm->sm_phys->smp_alloc;
+ sm->sm_length = sm->sm_phys->smp_objsize;
}
-void
-space_map_ref_add_seg(avl_tree_t *t, uint64_t start, uint64_t end,
- int64_t refcnt)
+uint64_t
+space_map_alloc(objset_t *os, dmu_tx_t *tx)
{
- space_map_ref_add_node(t, start, refcnt);
- space_map_ref_add_node(t, end, -refcnt);
+ spa_t *spa = dmu_objset_spa(os);
+ uint64_t object;
+ int bonuslen;
+
+ if (spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM)) {
+ spa_feature_incr(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM, tx);
+ bonuslen = sizeof (space_map_phys_t);
+ ASSERT3U(bonuslen, <=, dmu_bonus_max());
+ } else {
+ bonuslen = SPACE_MAP_SIZE_V0;
+ }
+
+ object = dmu_object_alloc(os,
+ DMU_OT_SPACE_MAP, space_map_blksz,
+ DMU_OT_SPACE_MAP_HEADER, bonuslen, tx);
+
+ return (object);
}
-/*
- * 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_map_free(space_map_t *sm, dmu_tx_t *tx)
{
- space_seg_t *ss;
+ spa_t *spa;
- ASSERT(MUTEX_HELD(sm->sm_lock));
+ if (sm == NULL)
+ return;
+
+ spa = dmu_objset_spa(sm->sm_os);
+ if (spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM)) {
+ dmu_object_info_t doi;
+
+ dmu_object_info_from_db(sm->sm_dbuf, &doi);
+ if (doi.doi_bonus_size != SPACE_MAP_SIZE_V0) {
+ VERIFY(spa_feature_is_active(spa,
+ SPA_FEATURE_SPACEMAP_HISTOGRAM));
+ spa_feature_decr(spa,
+ SPA_FEATURE_SPACEMAP_HISTOGRAM, tx);
+ }
+ }
- 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);
+ VERIFY3U(dmu_object_free(sm->sm_os, space_map_object(sm), tx), ==, 0);
+ sm->sm_object = 0;
+}
+
+uint64_t
+space_map_object(space_map_t *sm)
+{
+ return (sm != NULL ? sm->sm_object : 0);
}
/*
- * Convert a reference tree into a space map. The space map will contain
- * all members of the reference tree for which refcnt >= minref.
+ * Returns the already synced, on-disk allocated space.
*/
-void
-space_map_ref_generate_map(avl_tree_t *t, space_map_t *sm, int64_t minref)
+uint64_t
+space_map_allocated(space_map_t *sm)
{
- uint64_t start = -1ULL;
- int64_t refcnt = 0;
- space_ref_t *sr;
-
- ASSERT(MUTEX_HELD(sm->sm_lock));
+ return (sm != NULL ? sm->sm_alloc : 0);
+}
- space_map_vacate(sm, NULL, NULL);
+/*
+ * Returns the already synced, on-disk length;
+ */
+uint64_t
+space_map_length(space_map_t *sm)
+{
+ return (sm != NULL ? sm->sm_length : 0);
+}
- 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);
+/*
+ * Returns the allocated space that is currently syncing.
+ */
+int64_t
+space_map_alloc_delta(space_map_t *sm)
+{
+ if (sm == NULL)
+ return (0);
+ ASSERT(sm->sm_dbuf != NULL);
+ return (sm->sm_phys->smp_alloc - space_map_allocated(sm));
}
projects / mirror_zfs-debian.git / blobdiff