diff options
Diffstat (limited to 'sys/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c')
-rw-r--r-- | sys/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c | 855 |
1 files changed, 855 insertions, 0 deletions
diff --git a/sys/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c b/sys/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c new file mode 100644 index 0000000..9b7e23c --- /dev/null +++ b/sys/contrib/opensolaris/uts/common/fs/zfs/zap_micro.c @@ -0,0 +1,855 @@ +/* + * 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 2006 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <sys/spa.h> +#include <sys/dmu.h> +#include <sys/zfs_context.h> +#include <sys/zap.h> +#include <sys/refcount.h> +#include <sys/zap_impl.h> +#include <sys/zap_leaf.h> +#include <sys/avl.h> + + +static void mzap_upgrade(zap_t *zap, dmu_tx_t *tx); + + +static void +mzap_byteswap(mzap_phys_t *buf, size_t size) +{ + int i, max; + buf->mz_block_type = BSWAP_64(buf->mz_block_type); + buf->mz_salt = BSWAP_64(buf->mz_salt); + max = (size / MZAP_ENT_LEN) - 1; + for (i = 0; i < max; i++) { + buf->mz_chunk[i].mze_value = + BSWAP_64(buf->mz_chunk[i].mze_value); + buf->mz_chunk[i].mze_cd = + BSWAP_32(buf->mz_chunk[i].mze_cd); + } +} + +void +zap_byteswap(void *buf, size_t size) +{ + uint64_t block_type; + + block_type = *(uint64_t *)buf; + + if (block_type == ZBT_MICRO || block_type == BSWAP_64(ZBT_MICRO)) { + /* ASSERT(magic == ZAP_LEAF_MAGIC); */ + mzap_byteswap(buf, size); + } else { + fzap_byteswap(buf, size); + } +} + +static int +mze_compare(const void *arg1, const void *arg2) +{ + const mzap_ent_t *mze1 = arg1; + const mzap_ent_t *mze2 = arg2; + + if (mze1->mze_hash > mze2->mze_hash) + return (+1); + if (mze1->mze_hash < mze2->mze_hash) + return (-1); + if (mze1->mze_phys.mze_cd > mze2->mze_phys.mze_cd) + return (+1); + if (mze1->mze_phys.mze_cd < mze2->mze_phys.mze_cd) + return (-1); + return (0); +} + +static void +mze_insert(zap_t *zap, int chunkid, uint64_t hash, mzap_ent_phys_t *mzep) +{ + mzap_ent_t *mze; + + ASSERT(zap->zap_ismicro); + ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); + ASSERT(mzep->mze_cd < ZAP_MAXCD); + ASSERT3U(zap_hash(zap, mzep->mze_name), ==, hash); + + mze = kmem_alloc(sizeof (mzap_ent_t), KM_SLEEP); + mze->mze_chunkid = chunkid; + mze->mze_hash = hash; + mze->mze_phys = *mzep; + avl_add(&zap->zap_m.zap_avl, mze); +} + +static mzap_ent_t * +mze_find(zap_t *zap, const char *name, uint64_t hash) +{ + mzap_ent_t mze_tofind; + mzap_ent_t *mze; + avl_index_t idx; + avl_tree_t *avl = &zap->zap_m.zap_avl; + + ASSERT(zap->zap_ismicro); + ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); + ASSERT3U(zap_hash(zap, name), ==, hash); + + if (strlen(name) >= sizeof (mze_tofind.mze_phys.mze_name)) + return (NULL); + + mze_tofind.mze_hash = hash; + mze_tofind.mze_phys.mze_cd = 0; + + mze = avl_find(avl, &mze_tofind, &idx); + if (mze == NULL) + mze = avl_nearest(avl, idx, AVL_AFTER); + for (; mze && mze->mze_hash == hash; mze = AVL_NEXT(avl, mze)) { + if (strcmp(name, mze->mze_phys.mze_name) == 0) + return (mze); + } + return (NULL); +} + +static uint32_t +mze_find_unused_cd(zap_t *zap, uint64_t hash) +{ + mzap_ent_t mze_tofind; + mzap_ent_t *mze; + avl_index_t idx; + avl_tree_t *avl = &zap->zap_m.zap_avl; + uint32_t cd; + + ASSERT(zap->zap_ismicro); + ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); + + mze_tofind.mze_hash = hash; + mze_tofind.mze_phys.mze_cd = 0; + + cd = 0; + for (mze = avl_find(avl, &mze_tofind, &idx); + mze && mze->mze_hash == hash; mze = AVL_NEXT(avl, mze)) { + if (mze->mze_phys.mze_cd != cd) + break; + cd++; + } + + return (cd); +} + +static void +mze_remove(zap_t *zap, mzap_ent_t *mze) +{ + ASSERT(zap->zap_ismicro); + ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); + + avl_remove(&zap->zap_m.zap_avl, mze); + kmem_free(mze, sizeof (mzap_ent_t)); +} + +static void +mze_destroy(zap_t *zap) +{ + mzap_ent_t *mze; + void *avlcookie = NULL; + + while (mze = avl_destroy_nodes(&zap->zap_m.zap_avl, &avlcookie)) + kmem_free(mze, sizeof (mzap_ent_t)); + avl_destroy(&zap->zap_m.zap_avl); +} + +static zap_t * +mzap_open(objset_t *os, uint64_t obj, dmu_buf_t *db) +{ + zap_t *winner; + zap_t *zap; + int i; + + ASSERT3U(MZAP_ENT_LEN, ==, sizeof (mzap_ent_phys_t)); + + zap = kmem_zalloc(sizeof (zap_t), KM_SLEEP); + rw_init(&zap->zap_rwlock, NULL, RW_DEFAULT, 0); + rw_enter(&zap->zap_rwlock, RW_WRITER); + zap->zap_objset = os; + zap->zap_object = obj; + zap->zap_dbuf = db; + + if (((uint64_t *)db->db_data)[0] != ZBT_MICRO) { + mutex_init(&zap->zap_f.zap_num_entries_mtx, NULL, + MUTEX_DEFAULT, 0); + zap->zap_f.zap_block_shift = highbit(db->db_size) - 1; + } else { + zap->zap_ismicro = TRUE; + } + + /* + * Make sure that zap_ismicro is set before we let others see + * it, because zap_lockdir() checks zap_ismicro without the lock + * held. + */ + winner = dmu_buf_set_user(db, zap, &zap->zap_m.zap_phys, zap_evict); + + if (winner != NULL) { + if (!zap->zap_ismicro) + mutex_destroy(&zap->zap_f.zap_num_entries_mtx); + kmem_free(zap, sizeof (zap_t)); + return (winner); + } + + if (zap->zap_ismicro) { + zap->zap_salt = zap->zap_m.zap_phys->mz_salt; + zap->zap_m.zap_num_chunks = db->db_size / MZAP_ENT_LEN - 1; + avl_create(&zap->zap_m.zap_avl, mze_compare, + sizeof (mzap_ent_t), offsetof(mzap_ent_t, mze_node)); + + for (i = 0; i < zap->zap_m.zap_num_chunks; i++) { + mzap_ent_phys_t *mze = + &zap->zap_m.zap_phys->mz_chunk[i]; + if (mze->mze_name[0]) { + zap->zap_m.zap_num_entries++; + mze_insert(zap, i, + zap_hash(zap, mze->mze_name), mze); + } + } + } else { + zap->zap_salt = zap->zap_f.zap_phys->zap_salt; + + ASSERT3U(sizeof (struct zap_leaf_header), ==, + 2*ZAP_LEAF_CHUNKSIZE); + + /* + * The embedded pointer table should not overlap the + * other members. + */ + ASSERT3P(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0), >, + &zap->zap_f.zap_phys->zap_salt); + + /* + * The embedded pointer table should end at the end of + * the block + */ + ASSERT3U((uintptr_t)&ZAP_EMBEDDED_PTRTBL_ENT(zap, + 1<<ZAP_EMBEDDED_PTRTBL_SHIFT(zap)) - + (uintptr_t)zap->zap_f.zap_phys, ==, + zap->zap_dbuf->db_size); + } + rw_exit(&zap->zap_rwlock); + return (zap); +} + +int +zap_lockdir(objset_t *os, uint64_t obj, dmu_tx_t *tx, + krw_t lti, int fatreader, zap_t **zapp) +{ + zap_t *zap; + dmu_buf_t *db; + krw_t lt; + int err; + + *zapp = NULL; + + err = dmu_buf_hold(os, obj, 0, NULL, &db); + if (err) + return (err); + +#ifdef ZFS_DEBUG + { + dmu_object_info_t doi; + dmu_object_info_from_db(db, &doi); + ASSERT(dmu_ot[doi.doi_type].ot_byteswap == zap_byteswap); + } +#endif + + zap = dmu_buf_get_user(db); + if (zap == NULL) + zap = mzap_open(os, obj, db); + + /* + * We're checking zap_ismicro without the lock held, in order to + * tell what type of lock we want. Once we have some sort of + * lock, see if it really is the right type. In practice this + * can only be different if it was upgraded from micro to fat, + * and micro wanted WRITER but fat only needs READER. + */ + lt = (!zap->zap_ismicro && fatreader) ? RW_READER : lti; + rw_enter(&zap->zap_rwlock, lt); + if (lt != ((!zap->zap_ismicro && fatreader) ? RW_READER : lti)) { + /* it was upgraded, now we only need reader */ + ASSERT(lt == RW_WRITER); + ASSERT(RW_READER == + (!zap->zap_ismicro && fatreader) ? RW_READER : lti); + rw_downgrade(&zap->zap_rwlock); + lt = RW_READER; + } + + zap->zap_objset = os; + + if (lt == RW_WRITER) + dmu_buf_will_dirty(db, tx); + + ASSERT3P(zap->zap_dbuf, ==, db); + + ASSERT(!zap->zap_ismicro || + zap->zap_m.zap_num_entries <= zap->zap_m.zap_num_chunks); + if (zap->zap_ismicro && tx && + zap->zap_m.zap_num_entries == zap->zap_m.zap_num_chunks) { + uint64_t newsz = db->db_size + SPA_MINBLOCKSIZE; + if (newsz > MZAP_MAX_BLKSZ) { + dprintf("upgrading obj %llu: num_entries=%u\n", + obj, zap->zap_m.zap_num_entries); + mzap_upgrade(zap, tx); + *zapp = zap; + return (0); + } + err = dmu_object_set_blocksize(os, obj, newsz, 0, tx); + ASSERT3U(err, ==, 0); + zap->zap_m.zap_num_chunks = + db->db_size / MZAP_ENT_LEN - 1; + } + + *zapp = zap; + return (0); +} + +void +zap_unlockdir(zap_t *zap) +{ + rw_exit(&zap->zap_rwlock); + dmu_buf_rele(zap->zap_dbuf, NULL); +} + +static void +mzap_upgrade(zap_t *zap, dmu_tx_t *tx) +{ + mzap_phys_t *mzp; + int i, sz, nchunks, err; + + ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); + + sz = zap->zap_dbuf->db_size; + mzp = kmem_alloc(sz, KM_SLEEP); + bcopy(zap->zap_dbuf->db_data, mzp, sz); + nchunks = zap->zap_m.zap_num_chunks; + + err = dmu_object_set_blocksize(zap->zap_objset, zap->zap_object, + 1ULL << fzap_default_block_shift, 0, tx); + ASSERT(err == 0); + + dprintf("upgrading obj=%llu with %u chunks\n", + zap->zap_object, nchunks); + mze_destroy(zap); + + fzap_upgrade(zap, tx); + + for (i = 0; i < nchunks; i++) { + int err; + mzap_ent_phys_t *mze = &mzp->mz_chunk[i]; + if (mze->mze_name[0] == 0) + continue; + dprintf("adding %s=%llu\n", + mze->mze_name, mze->mze_value); + err = fzap_add_cd(zap, + mze->mze_name, 8, 1, &mze->mze_value, + mze->mze_cd, tx); + ASSERT3U(err, ==, 0); + } + kmem_free(mzp, sz); +} + +uint64_t +zap_hash(zap_t *zap, const char *name) +{ + const uint8_t *cp; + uint8_t c; + uint64_t crc = zap->zap_salt; + + ASSERT(crc != 0); + ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY); + for (cp = (const uint8_t *)name; (c = *cp) != '\0'; cp++) + crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ c) & 0xFF]; + + /* + * Only use 28 bits, since we need 4 bits in the cookie for the + * collision differentiator. We MUST use the high bits, since + * those are the onces that we first pay attention to when + * chosing the bucket. + */ + crc &= ~((1ULL << (64 - ZAP_HASHBITS)) - 1); + + return (crc); +} + + +static void +mzap_create_impl(objset_t *os, uint64_t obj, dmu_tx_t *tx) +{ + dmu_buf_t *db; + mzap_phys_t *zp; + + VERIFY(0 == dmu_buf_hold(os, obj, 0, FTAG, &db)); + +#ifdef ZFS_DEBUG + { + dmu_object_info_t doi; + dmu_object_info_from_db(db, &doi); + ASSERT(dmu_ot[doi.doi_type].ot_byteswap == zap_byteswap); + } +#endif + + dmu_buf_will_dirty(db, tx); + zp = db->db_data; + zp->mz_block_type = ZBT_MICRO; + zp->mz_salt = ((uintptr_t)db ^ (uintptr_t)tx ^ (obj << 1)) | 1ULL; + ASSERT(zp->mz_salt != 0); + dmu_buf_rele(db, FTAG); +} + +int +zap_create_claim(objset_t *os, uint64_t obj, dmu_object_type_t ot, + dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) +{ + int err; + + err = dmu_object_claim(os, obj, ot, 0, bonustype, bonuslen, tx); + if (err != 0) + return (err); + mzap_create_impl(os, obj, tx); + return (0); +} + +uint64_t +zap_create(objset_t *os, dmu_object_type_t ot, + dmu_object_type_t bonustype, int bonuslen, dmu_tx_t *tx) +{ + uint64_t obj = dmu_object_alloc(os, ot, 0, bonustype, bonuslen, tx); + + mzap_create_impl(os, obj, tx); + return (obj); +} + +int +zap_destroy(objset_t *os, uint64_t zapobj, dmu_tx_t *tx) +{ + /* + * dmu_object_free will free the object number and free the + * data. Freeing the data will cause our pageout function to be + * called, which will destroy our data (zap_leaf_t's and zap_t). + */ + + return (dmu_object_free(os, zapobj, tx)); +} + +_NOTE(ARGSUSED(0)) +void +zap_evict(dmu_buf_t *db, void *vzap) +{ + zap_t *zap = vzap; + + rw_destroy(&zap->zap_rwlock); + + if (zap->zap_ismicro) + mze_destroy(zap); + else + mutex_destroy(&zap->zap_f.zap_num_entries_mtx); + + kmem_free(zap, sizeof (zap_t)); +} + +int +zap_count(objset_t *os, uint64_t zapobj, uint64_t *count) +{ + zap_t *zap; + int err; + + err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); + if (err) + return (err); + if (!zap->zap_ismicro) { + err = fzap_count(zap, count); + } else { + *count = zap->zap_m.zap_num_entries; + } + zap_unlockdir(zap); + return (err); +} + +/* + * Routines for maniplulating attributes. + */ + +int +zap_lookup(objset_t *os, uint64_t zapobj, const char *name, + uint64_t integer_size, uint64_t num_integers, void *buf) +{ + zap_t *zap; + int err; + mzap_ent_t *mze; + + err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); + if (err) + return (err); + if (!zap->zap_ismicro) { + err = fzap_lookup(zap, name, + integer_size, num_integers, buf); + } else { + mze = mze_find(zap, name, zap_hash(zap, name)); + if (mze == NULL) { + err = ENOENT; + } else { + if (num_integers < 1) + err = EOVERFLOW; + else if (integer_size != 8) + err = EINVAL; + else + *(uint64_t *)buf = mze->mze_phys.mze_value; + } + } + zap_unlockdir(zap); + return (err); +} + +int +zap_length(objset_t *os, uint64_t zapobj, const char *name, + uint64_t *integer_size, uint64_t *num_integers) +{ + zap_t *zap; + int err; + mzap_ent_t *mze; + + err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); + if (err) + return (err); + if (!zap->zap_ismicro) { + err = fzap_length(zap, name, integer_size, num_integers); + } else { + mze = mze_find(zap, name, zap_hash(zap, name)); + if (mze == NULL) { + err = ENOENT; + } else { + if (integer_size) + *integer_size = 8; + if (num_integers) + *num_integers = 1; + } + } + zap_unlockdir(zap); + return (err); +} + +static void +mzap_addent(zap_t *zap, const char *name, uint64_t hash, uint64_t value) +{ + int i; + int start = zap->zap_m.zap_alloc_next; + uint32_t cd; + + dprintf("obj=%llu %s=%llu\n", zap->zap_object, name, value); + ASSERT(RW_WRITE_HELD(&zap->zap_rwlock)); + +#ifdef ZFS_DEBUG + for (i = 0; i < zap->zap_m.zap_num_chunks; i++) { + mzap_ent_phys_t *mze = &zap->zap_m.zap_phys->mz_chunk[i]; + ASSERT(strcmp(name, mze->mze_name) != 0); + } +#endif + + cd = mze_find_unused_cd(zap, hash); + /* given the limited size of the microzap, this can't happen */ + ASSERT(cd != ZAP_MAXCD); + +again: + for (i = start; i < zap->zap_m.zap_num_chunks; i++) { + mzap_ent_phys_t *mze = &zap->zap_m.zap_phys->mz_chunk[i]; + if (mze->mze_name[0] == 0) { + mze->mze_value = value; + mze->mze_cd = cd; + (void) strcpy(mze->mze_name, name); + zap->zap_m.zap_num_entries++; + zap->zap_m.zap_alloc_next = i+1; + if (zap->zap_m.zap_alloc_next == + zap->zap_m.zap_num_chunks) + zap->zap_m.zap_alloc_next = 0; + mze_insert(zap, i, hash, mze); + return; + } + } + if (start != 0) { + start = 0; + goto again; + } + ASSERT(!"out of entries!"); +} + +int +zap_add(objset_t *os, uint64_t zapobj, const char *name, + int integer_size, uint64_t num_integers, + const void *val, dmu_tx_t *tx) +{ + zap_t *zap; + int err; + mzap_ent_t *mze; + const uint64_t *intval = val; + uint64_t hash; + + err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, &zap); + if (err) + return (err); + if (!zap->zap_ismicro) { + err = fzap_add(zap, name, integer_size, num_integers, val, tx); + } else if (integer_size != 8 || num_integers != 1 || + strlen(name) >= MZAP_NAME_LEN) { + dprintf("upgrading obj %llu: intsz=%u numint=%llu name=%s\n", + zapobj, integer_size, num_integers, name); + mzap_upgrade(zap, tx); + err = fzap_add(zap, name, integer_size, num_integers, val, tx); + } else { + hash = zap_hash(zap, name); + mze = mze_find(zap, name, hash); + if (mze != NULL) { + err = EEXIST; + } else { + mzap_addent(zap, name, hash, *intval); + } + } + zap_unlockdir(zap); + return (err); +} + +int +zap_update(objset_t *os, uint64_t zapobj, const char *name, + int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx) +{ + zap_t *zap; + mzap_ent_t *mze; + const uint64_t *intval = val; + uint64_t hash; + int err; + + err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, &zap); + if (err) + return (err); + ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); + if (!zap->zap_ismicro) { + err = fzap_update(zap, name, + integer_size, num_integers, val, tx); + } else if (integer_size != 8 || num_integers != 1 || + strlen(name) >= MZAP_NAME_LEN) { + dprintf("upgrading obj %llu: intsz=%u numint=%llu name=%s\n", + zapobj, integer_size, num_integers, name); + mzap_upgrade(zap, tx); + err = fzap_update(zap, name, + integer_size, num_integers, val, tx); + } else { + hash = zap_hash(zap, name); + mze = mze_find(zap, name, hash); + if (mze != NULL) { + mze->mze_phys.mze_value = *intval; + zap->zap_m.zap_phys->mz_chunk + [mze->mze_chunkid].mze_value = *intval; + } else { + mzap_addent(zap, name, hash, *intval); + } + } + zap_unlockdir(zap); + return (err); +} + +int +zap_remove(objset_t *os, uint64_t zapobj, const char *name, dmu_tx_t *tx) +{ + zap_t *zap; + int err; + mzap_ent_t *mze; + + err = zap_lockdir(os, zapobj, tx, RW_WRITER, TRUE, &zap); + if (err) + return (err); + if (!zap->zap_ismicro) { + err = fzap_remove(zap, name, tx); + } else { + mze = mze_find(zap, name, zap_hash(zap, name)); + if (mze == NULL) { + dprintf("fail: %s\n", name); + err = ENOENT; + } else { + dprintf("success: %s\n", name); + zap->zap_m.zap_num_entries--; + bzero(&zap->zap_m.zap_phys->mz_chunk[mze->mze_chunkid], + sizeof (mzap_ent_phys_t)); + mze_remove(zap, mze); + } + } + zap_unlockdir(zap); + return (err); +} + + +/* + * Routines for iterating over the attributes. + */ + +/* + * We want to keep the high 32 bits of the cursor zero if we can, so + * that 32-bit programs can access this. So use a small hash value so + * we can fit 4 bits of cd into the 32-bit cursor. + * + * [ 4 zero bits | 32-bit collision differentiator | 28-bit hash value ] + */ +void +zap_cursor_init_serialized(zap_cursor_t *zc, objset_t *os, uint64_t zapobj, + uint64_t serialized) +{ + zc->zc_objset = os; + zc->zc_zap = NULL; + zc->zc_leaf = NULL; + zc->zc_zapobj = zapobj; + if (serialized == -1ULL) { + zc->zc_hash = -1ULL; + zc->zc_cd = 0; + } else { + zc->zc_hash = serialized << (64-ZAP_HASHBITS); + zc->zc_cd = serialized >> ZAP_HASHBITS; + if (zc->zc_cd >= ZAP_MAXCD) /* corrupt serialized */ + zc->zc_cd = 0; + } +} + +void +zap_cursor_init(zap_cursor_t *zc, objset_t *os, uint64_t zapobj) +{ + zap_cursor_init_serialized(zc, os, zapobj, 0); +} + +void +zap_cursor_fini(zap_cursor_t *zc) +{ + if (zc->zc_zap) { + rw_enter(&zc->zc_zap->zap_rwlock, RW_READER); + zap_unlockdir(zc->zc_zap); + zc->zc_zap = NULL; + } + if (zc->zc_leaf) { + rw_enter(&zc->zc_leaf->l_rwlock, RW_READER); + zap_put_leaf(zc->zc_leaf); + zc->zc_leaf = NULL; + } + zc->zc_objset = NULL; +} + +uint64_t +zap_cursor_serialize(zap_cursor_t *zc) +{ + if (zc->zc_hash == -1ULL) + return (-1ULL); + ASSERT((zc->zc_hash & (ZAP_MAXCD-1)) == 0); + ASSERT(zc->zc_cd < ZAP_MAXCD); + return ((zc->zc_hash >> (64-ZAP_HASHBITS)) | + ((uint64_t)zc->zc_cd << ZAP_HASHBITS)); +} + +int +zap_cursor_retrieve(zap_cursor_t *zc, zap_attribute_t *za) +{ + int err; + avl_index_t idx; + mzap_ent_t mze_tofind; + mzap_ent_t *mze; + + if (zc->zc_hash == -1ULL) + return (ENOENT); + + if (zc->zc_zap == NULL) { + err = zap_lockdir(zc->zc_objset, zc->zc_zapobj, NULL, + RW_READER, TRUE, &zc->zc_zap); + if (err) + return (err); + } else { + rw_enter(&zc->zc_zap->zap_rwlock, RW_READER); + } + if (!zc->zc_zap->zap_ismicro) { + err = fzap_cursor_retrieve(zc->zc_zap, zc, za); + } else { + err = ENOENT; + + mze_tofind.mze_hash = zc->zc_hash; + mze_tofind.mze_phys.mze_cd = zc->zc_cd; + + mze = avl_find(&zc->zc_zap->zap_m.zap_avl, &mze_tofind, &idx); + ASSERT(mze == NULL || 0 == bcmp(&mze->mze_phys, + &zc->zc_zap->zap_m.zap_phys->mz_chunk[mze->mze_chunkid], + sizeof (mze->mze_phys))); + if (mze == NULL) { + mze = avl_nearest(&zc->zc_zap->zap_m.zap_avl, + idx, AVL_AFTER); + } + if (mze) { + za->za_integer_length = 8; + za->za_num_integers = 1; + za->za_first_integer = mze->mze_phys.mze_value; + (void) strcpy(za->za_name, mze->mze_phys.mze_name); + zc->zc_hash = mze->mze_hash; + zc->zc_cd = mze->mze_phys.mze_cd; + err = 0; + } else { + zc->zc_hash = -1ULL; + } + } + rw_exit(&zc->zc_zap->zap_rwlock); + return (err); +} + +void +zap_cursor_advance(zap_cursor_t *zc) +{ + if (zc->zc_hash == -1ULL) + return; + zc->zc_cd++; + if (zc->zc_cd >= ZAP_MAXCD) { + zc->zc_cd = 0; + zc->zc_hash += 1ULL<<(64-ZAP_HASHBITS); + if (zc->zc_hash == 0) /* EOF */ + zc->zc_hash = -1ULL; + } +} + +int +zap_get_stats(objset_t *os, uint64_t zapobj, zap_stats_t *zs) +{ + int err; + zap_t *zap; + + err = zap_lockdir(os, zapobj, NULL, RW_READER, TRUE, &zap); + if (err) + return (err); + + bzero(zs, sizeof (zap_stats_t)); + + if (zap->zap_ismicro) { + zs->zs_blocksize = zap->zap_dbuf->db_size; + zs->zs_num_entries = zap->zap_m.zap_num_entries; + zs->zs_num_blocks = 1; + } else { + fzap_get_stats(zap, zs); + } + zap_unlockdir(zap); + return (0); +} |