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-rw-r--r--sys/cddl/contrib/opensolaris/uts/common/fs/zfs/space_map.c603
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diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/space_map.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/space_map.c
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+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/space_map.c
@@ -0,0 +1,603 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+/*
+ * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+/*
+ * 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>
+#include <sys/refcount.h>
+#include <sys/zfeature.h>
+
+/*
+ * This value controls how the space map's block size is allowed to grow.
+ * If the value is set to the same size as SPACE_MAP_INITIAL_BLOCKSIZE then
+ * the space map block size will remain fixed. Setting this value to something
+ * greater than SPACE_MAP_INITIAL_BLOCKSIZE will allow the space map to
+ * increase its block size as needed. To maintain backwards compatibilty the
+ * space map's block size must be a power of 2 and SPACE_MAP_INITIAL_BLOCKSIZE
+ * or larger.
+ */
+int space_map_max_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, range_tree_t *rt, maptype_t maptype)
+{
+ uint64_t *entry, *entry_map, *entry_map_end;
+ uint64_t bufsize, size, offset, end, space;
+ int error = 0;
+
+ ASSERT(MUTEX_HELD(sm->sm_lock));
+
+ end = space_map_length(sm);
+ space = space_map_allocated(sm);
+
+ VERIFY0(range_tree_space(rt));
+
+ if (maptype == SM_FREE) {
+ range_tree_add(rt, sm->sm_start, sm->sm_size);
+ space = sm->sm_size - space;
+ }
+
+ bufsize = MAX(sm->sm_blksz, SPA_MINBLOCKSIZE);
+ entry_map = zio_buf_alloc(bufsize);
+
+ mutex_exit(sm->sm_lock);
+ 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",
+ space_map_object(sm), offset, size);
+
+ mutex_exit(sm->sm_lock);
+ 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;
+
+ 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(range_tree_space(rt), ==, space);
+ else
+ range_tree_vacate(rt, NULL, NULL);
+
+ zio_buf_free(entry_map, bufsize);
+ return (error);
+}
+
+void
+space_map_histogram_clear(space_map_t *sm)
+{
+ if (sm->sm_dbuf->db_size != sizeof (space_map_phys_t))
+ return;
+
+ bzero(sm->sm_phys->smp_histogram, sizeof (sm->sm_phys->smp_histogram));
+}
+
+boolean_t
+space_map_histogram_verify(space_map_t *sm, range_tree_t *rt)
+{
+ /*
+ * Verify that the in-core range tree does not have any
+ * ranges smaller than our sm_shift size.
+ */
+ for (int i = 0; i < sm->sm_shift; i++) {
+ if (rt->rt_histogram[i] != 0)
+ return (B_FALSE);
+ }
+ return (B_TRUE);
+}
+
+void
+space_map_histogram_add(space_map_t *sm, range_tree_t *rt, dmu_tx_t *tx)
+{
+ int idx = 0;
+
+ 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 (int 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(sm) - 1) {
+ ASSERT3U(idx + sm->sm_shift, ==, i);
+ idx++;
+ ASSERT3U(idx, <, SPACE_MAP_HISTOGRAM_SIZE(sm));
+ }
+ }
+}
+
+uint64_t
+space_map_entries(space_map_t *sm, range_tree_t *rt)
+{
+ 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);
+}
+
+void
+space_map_set_blocksize(space_map_t *sm, uint64_t size, dmu_tx_t *tx)
+{
+ uint32_t blksz;
+ u_longlong_t blocks;
+
+ ASSERT3U(sm->sm_blksz, !=, 0);
+ ASSERT3U(space_map_object(sm), !=, 0);
+ ASSERT(sm->sm_dbuf != NULL);
+ VERIFY(ISP2(space_map_max_blksz));
+
+ if (sm->sm_blksz >= space_map_max_blksz)
+ return;
+
+ /*
+ * The object contains more than one block so we can't adjust
+ * its size.
+ */
+ if (sm->sm_phys->smp_objsize > sm->sm_blksz)
+ return;
+
+ if (size > sm->sm_blksz) {
+ uint64_t newsz;
+
+ /*
+ * Older software versions treat space map blocks as fixed
+ * entities. The DMU is capable of handling different block
+ * sizes making it possible for us to increase the
+ * block size and maintain backwards compatibility. The
+ * caveat is that the new block sizes must be a
+ * power of 2 so that old software can append to the file,
+ * adding more blocks. The block size can grow until it
+ * reaches space_map_max_blksz.
+ */
+ newsz = ISP2(size) ? size : 1ULL << highbit64(size);
+ if (newsz > space_map_max_blksz)
+ newsz = space_map_max_blksz;
+
+ VERIFY0(dmu_object_set_blocksize(sm->sm_os,
+ space_map_object(sm), newsz, 0, tx));
+ dmu_object_size_from_db(sm->sm_dbuf, &blksz, &blocks);
+
+ zfs_dbgmsg("txg %llu, spa %s, increasing blksz from %d to %d",
+ dmu_tx_get_txg(tx), spa_name(dmu_objset_spa(sm->sm_os)),
+ sm->sm_blksz, blksz);
+
+ VERIFY3U(newsz, ==, blksz);
+ VERIFY3U(sm->sm_blksz, <, blksz);
+ sm->sm_blksz = blksz;
+ }
+}
+
+/*
+ * Note: space_map_write() will drop sm_lock across dmu_write() calls.
+ */
+void
+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 = &rt->rt_root;
+ range_seg_t *rs;
+ uint64_t size, total, rt_space, nodes;
+ uint64_t *entry, *entry_map, *entry_map_end;
+ uint64_t newsz, expected_entries, actual_entries = 1;
+
+ 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);
+
+ /*
+ * 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;
+
+ if (range_tree_space(rt) == 0) {
+ VERIFY3U(sm->sm_object, ==, sm->sm_phys->smp_object);
+ return;
+ }
+
+ if (maptype == SM_ALLOC)
+ sm->sm_phys->smp_alloc += range_tree_space(rt);
+ else
+ sm->sm_phys->smp_alloc -= range_tree_space(rt);
+
+ expected_entries = space_map_entries(sm, rt);
+
+ /*
+ * Calculate the new size for the space map on-disk and see if
+ * we can grow the block size to accommodate the new size.
+ */
+ newsz = sm->sm_phys->smp_objsize + expected_entries * sizeof (uint64_t);
+ space_map_set_blocksize(sm, newsz, tx);
+
+ 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_ACTION_ENCODE(maptype) |
+ SM_DEBUG_SYNCPASS_ENCODE(spa_sync_pass(spa)) |
+ SM_DEBUG_TXG_ENCODE(dmu_tx_get_txg(tx));
+
+ total = 0;
+ 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 << sm->sm_shift;
+
+ while (size != 0) {
+ uint64_t run_len;
+
+ run_len = MIN(size, SM_RUN_MAX);
+
+ if (entry == entry_map_end) {
+ 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;
+ }
+
+ *entry++ = SM_OFFSET_ENCODE(start) |
+ SM_TYPE_ENCODE(maptype) |
+ SM_RUN_ENCODE(run_len);
+
+ start += run_len;
+ size -= run_len;
+ actual_entries++;
+ }
+ }
+
+ if (entry != entry_map) {
+ size = (entry - entry_map) * sizeof (uint64_t);
+ mutex_exit(rt->rt_lock);
+ dmu_write(os, space_map_object(sm), sm->sm_phys->smp_objsize,
+ size, entry_map, tx);
+ 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(&rt->rt_root));
+ VERIFY3U(range_tree_space(rt), ==, rt_space);
+ VERIFY3U(range_tree_space(rt), ==, total);
+
+ zio_buf_free(entry_map, sm->sm_blksz);
+}
+
+static int
+space_map_open_impl(space_map_t *sm)
+{
+ int error;
+ u_longlong_t blocks;
+
+ error = dmu_bonus_hold(sm->sm_os, sm->sm_object, sm, &sm->sm_dbuf);
+ if (error)
+ return (error);
+
+ dmu_object_size_from_db(sm->sm_dbuf, &sm->sm_blksz, &blocks);
+ sm->sm_phys = sm->sm_dbuf->db_data;
+ return (0);
+}
+
+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)
+{
+ space_map_t *sm;
+ int error;
+
+ ASSERT(*smp == NULL);
+ ASSERT(os != NULL);
+ ASSERT(object != 0);
+
+ sm = kmem_zalloc(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;
+
+ error = space_map_open_impl(sm);
+ if (error != 0) {
+ space_map_close(sm);
+ return (error);
+ }
+
+ *smp = sm;
+
+ return (0);
+}
+
+void
+space_map_close(space_map_t *sm)
+{
+ 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));
+}
+
+static void
+space_map_reallocate(space_map_t *sm, dmu_tx_t *tx)
+{
+ ASSERT(dmu_tx_is_syncing(tx));
+
+ 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));
+}
+
+void
+space_map_truncate(space_map_t *sm, dmu_tx_t *tx)
+{
+ objset_t *os = sm->sm_os;
+ spa_t *spa = dmu_objset_spa(os);
+ dmu_object_info_t doi;
+ int bonuslen;
+
+ ASSERT(dsl_pool_sync_context(dmu_objset_pool(os)));
+ ASSERT(dmu_tx_is_syncing(tx));
+
+ VERIFY0(dmu_free_range(os, space_map_object(sm), 0, -1ULL, tx));
+ dmu_object_info_from_db(sm->sm_dbuf, &doi);
+
+ if (spa_feature_is_enabled(spa, SPA_FEATURE_SPACEMAP_HISTOGRAM)) {
+ bonuslen = sizeof (space_map_phys_t);
+ ASSERT3U(bonuslen, <=, dmu_bonus_max());
+ } else {
+ bonuslen = SPACE_MAP_SIZE_V0;
+ }
+
+ if (bonuslen != doi.doi_bonus_size ||
+ doi.doi_data_block_size != SPACE_MAP_INITIAL_BLOCKSIZE) {
+ zfs_dbgmsg("txg %llu, spa %s, reallocating: "
+ "old bonus %u, old blocksz %u", dmu_tx_get_txg(tx),
+ spa_name(spa), doi.doi_bonus_size, doi.doi_data_block_size);
+ space_map_reallocate(sm, tx);
+ VERIFY3U(sm->sm_blksz, ==, SPACE_MAP_INITIAL_BLOCKSIZE);
+ }
+
+ dmu_buf_will_dirty(sm->sm_dbuf, tx);
+ sm->sm_phys->smp_objsize = 0;
+ sm->sm_phys->smp_alloc = 0;
+}
+
+/*
+ * Update the in-core space_map allocation and length values.
+ */
+void
+space_map_update(space_map_t *sm)
+{
+ if (sm == NULL)
+ return;
+
+ ASSERT(MUTEX_HELD(sm->sm_lock));
+
+ sm->sm_alloc = sm->sm_phys->smp_alloc;
+ sm->sm_length = sm->sm_phys->smp_objsize;
+}
+
+uint64_t
+space_map_alloc(objset_t *os, dmu_tx_t *tx)
+{
+ 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_INITIAL_BLOCKSIZE,
+ DMU_OT_SPACE_MAP_HEADER, bonuslen, tx);
+
+ return (object);
+}
+
+void
+space_map_free(space_map_t *sm, dmu_tx_t *tx)
+{
+ spa_t *spa;
+
+ 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);
+ }
+ }
+
+ 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);
+}
+
+/*
+ * Returns the already synced, on-disk allocated space.
+ */
+uint64_t
+space_map_allocated(space_map_t *sm)
+{
+ return (sm != NULL ? sm->sm_alloc : 0);
+}
+
+/*
+ * Returns the already synced, on-disk length;
+ */
+uint64_t
+space_map_length(space_map_t *sm)
+{
+ return (sm != NULL ? sm->sm_length : 0);
+}
+
+/*
+ * 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));
+}
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