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authorpjd <pjd@FreeBSD.org>2007-04-06 01:09:06 +0000
committerpjd <pjd@FreeBSD.org>2007-04-06 01:09:06 +0000
commit3b005d330261f33318ca1ee3fef1940237fd788b (patch)
tree3061c8734d9ce560165e672836837a0f411a83c9 /sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c
parent3be454b8211f48e634e6587f53807d3b5013e973 (diff)
downloadFreeBSD-src-3b005d330261f33318ca1ee3fef1940237fd788b.zip
FreeBSD-src-3b005d330261f33318ca1ee3fef1940237fd788b.tar.gz
Please welcome ZFS - The last word in file systems.
ZFS file system was ported from OpenSolaris operating system. The code in under CDDL license. I'd like to thank all SUN developers that created this great piece of software. Supported by: Wheel LTD (http://www.wheel.pl/) Supported by: The FreeBSD Foundation (http://www.freebsdfoundation.org/) Supported by: Sentex (http://www.sentex.net/)
Diffstat (limited to 'sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c')
-rw-r--r--sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c1070
1 files changed, 1070 insertions, 0 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c
new file mode 100644
index 0000000..533431f
--- /dev/null
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zap.c
@@ -0,0 +1,1070 @@
+/*
+ * 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"
+
+
+/*
+ * This file contains the top half of the zfs directory structure
+ * implementation. The bottom half is in zap_leaf.c.
+ *
+ * The zdir is an extendable hash data structure. There is a table of
+ * pointers to buckets (zap_t->zd_data->zd_leafs). The buckets are
+ * each a constant size and hold a variable number of directory entries.
+ * The buckets (aka "leaf nodes") are implemented in zap_leaf.c.
+ *
+ * The pointer table holds a power of 2 number of pointers.
+ * (1<<zap_t->zd_data->zd_phys->zd_prefix_len). The bucket pointed to
+ * by the pointer at index i in the table holds entries whose hash value
+ * has a zd_prefix_len - bit prefix
+ */
+
+#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>
+
+int fzap_default_block_shift = 14; /* 16k blocksize */
+
+static void zap_leaf_pageout(dmu_buf_t *db, void *vl);
+static uint64_t zap_allocate_blocks(zap_t *zap, int nblocks);
+
+
+void
+fzap_byteswap(void *vbuf, size_t size)
+{
+ uint64_t block_type;
+
+ block_type = *(uint64_t *)vbuf;
+
+ if (block_type == ZBT_LEAF || block_type == BSWAP_64(ZBT_LEAF))
+ zap_leaf_byteswap(vbuf, size);
+ else {
+ /* it's a ptrtbl block */
+ byteswap_uint64_array(vbuf, size);
+ }
+}
+
+void
+fzap_upgrade(zap_t *zap, dmu_tx_t *tx)
+{
+ dmu_buf_t *db;
+ zap_leaf_t *l;
+ int i;
+ zap_phys_t *zp;
+
+ ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
+ zap->zap_ismicro = FALSE;
+
+ (void) dmu_buf_update_user(zap->zap_dbuf, zap, zap,
+ &zap->zap_f.zap_phys, zap_evict);
+
+ mutex_init(&zap->zap_f.zap_num_entries_mtx, NULL, MUTEX_DEFAULT, 0);
+ zap->zap_f.zap_block_shift = highbit(zap->zap_dbuf->db_size) - 1;
+
+ zp = zap->zap_f.zap_phys;
+ /*
+ * explicitly zero it since it might be coming from an
+ * initialized microzap
+ */
+ bzero(zap->zap_dbuf->db_data, zap->zap_dbuf->db_size);
+ zp->zap_block_type = ZBT_HEADER;
+ zp->zap_magic = ZAP_MAGIC;
+
+ zp->zap_ptrtbl.zt_shift = ZAP_EMBEDDED_PTRTBL_SHIFT(zap);
+
+ zp->zap_freeblk = 2; /* block 1 will be the first leaf */
+ zp->zap_num_leafs = 1;
+ zp->zap_num_entries = 0;
+ zp->zap_salt = zap->zap_salt;
+
+ /* block 1 will be the first leaf */
+ for (i = 0; i < (1<<zp->zap_ptrtbl.zt_shift); i++)
+ ZAP_EMBEDDED_PTRTBL_ENT(zap, i) = 1;
+
+ /*
+ * set up block 1 - the first leaf
+ */
+ VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ 1<<FZAP_BLOCK_SHIFT(zap), FTAG, &db));
+ dmu_buf_will_dirty(db, tx);
+
+ l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
+ l->l_dbuf = db;
+ l->l_phys = db->db_data;
+
+ zap_leaf_init(l);
+
+ kmem_free(l, sizeof (zap_leaf_t));
+ dmu_buf_rele(db, FTAG);
+}
+
+static int
+zap_tryupgradedir(zap_t *zap, dmu_tx_t *tx)
+{
+ if (RW_WRITE_HELD(&zap->zap_rwlock))
+ return (1);
+ if (rw_tryupgrade(&zap->zap_rwlock)) {
+ dmu_buf_will_dirty(zap->zap_dbuf, tx);
+ return (1);
+ }
+ return (0);
+}
+
+/*
+ * Generic routines for dealing with the pointer & cookie tables.
+ */
+
+static int
+zap_table_grow(zap_t *zap, zap_table_phys_t *tbl,
+ void (*transfer_func)(const uint64_t *src, uint64_t *dst, int n),
+ dmu_tx_t *tx)
+{
+ uint64_t b, newblk;
+ dmu_buf_t *db_old, *db_new;
+ int err;
+ int bs = FZAP_BLOCK_SHIFT(zap);
+ int hepb = 1<<(bs-4);
+ /* hepb = half the number of entries in a block */
+
+ ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
+ ASSERT(tbl->zt_blk != 0);
+ ASSERT(tbl->zt_numblks > 0);
+
+ if (tbl->zt_nextblk != 0) {
+ newblk = tbl->zt_nextblk;
+ } else {
+ newblk = zap_allocate_blocks(zap, tbl->zt_numblks * 2);
+ tbl->zt_nextblk = newblk;
+ ASSERT3U(tbl->zt_blks_copied, ==, 0);
+ dmu_prefetch(zap->zap_objset, zap->zap_object,
+ tbl->zt_blk << bs, tbl->zt_numblks << bs);
+ }
+
+ /*
+ * Copy the ptrtbl from the old to new location.
+ */
+
+ b = tbl->zt_blks_copied;
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (tbl->zt_blk + b) << bs, FTAG, &db_old);
+ if (err)
+ return (err);
+
+ /* first half of entries in old[b] go to new[2*b+0] */
+ VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (newblk + 2*b+0) << bs, FTAG, &db_new));
+ dmu_buf_will_dirty(db_new, tx);
+ transfer_func(db_old->db_data, db_new->db_data, hepb);
+ dmu_buf_rele(db_new, FTAG);
+
+ /* second half of entries in old[b] go to new[2*b+1] */
+ VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (newblk + 2*b+1) << bs, FTAG, &db_new));
+ dmu_buf_will_dirty(db_new, tx);
+ transfer_func((uint64_t *)db_old->db_data + hepb,
+ db_new->db_data, hepb);
+ dmu_buf_rele(db_new, FTAG);
+
+ dmu_buf_rele(db_old, FTAG);
+
+ tbl->zt_blks_copied++;
+
+ dprintf("copied block %llu of %llu\n",
+ tbl->zt_blks_copied, tbl->zt_numblks);
+
+ if (tbl->zt_blks_copied == tbl->zt_numblks) {
+ (void) dmu_free_range(zap->zap_objset, zap->zap_object,
+ tbl->zt_blk << bs, tbl->zt_numblks << bs, tx);
+
+ tbl->zt_blk = newblk;
+ tbl->zt_numblks *= 2;
+ tbl->zt_shift++;
+ tbl->zt_nextblk = 0;
+ tbl->zt_blks_copied = 0;
+
+ dprintf("finished; numblocks now %llu (%lluk entries)\n",
+ tbl->zt_numblks, 1<<(tbl->zt_shift-10));
+ }
+
+ return (0);
+}
+
+static int
+zap_table_store(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t val,
+ dmu_tx_t *tx)
+{
+ int err;
+ uint64_t blk, off;
+ int bs = FZAP_BLOCK_SHIFT(zap);
+ dmu_buf_t *db;
+
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+ ASSERT(tbl->zt_blk != 0);
+
+ dprintf("storing %llx at index %llx\n", val, idx);
+
+ blk = idx >> (bs-3);
+ off = idx & ((1<<(bs-3))-1);
+
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (tbl->zt_blk + blk) << bs, FTAG, &db);
+ if (err)
+ return (err);
+ dmu_buf_will_dirty(db, tx);
+
+ if (tbl->zt_nextblk != 0) {
+ uint64_t idx2 = idx * 2;
+ uint64_t blk2 = idx2 >> (bs-3);
+ uint64_t off2 = idx2 & ((1<<(bs-3))-1);
+ dmu_buf_t *db2;
+
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (tbl->zt_nextblk + blk2) << bs, FTAG, &db2);
+ if (err) {
+ dmu_buf_rele(db, FTAG);
+ return (err);
+ }
+ dmu_buf_will_dirty(db2, tx);
+ ((uint64_t *)db2->db_data)[off2] = val;
+ ((uint64_t *)db2->db_data)[off2+1] = val;
+ dmu_buf_rele(db2, FTAG);
+ }
+
+ ((uint64_t *)db->db_data)[off] = val;
+ dmu_buf_rele(db, FTAG);
+
+ return (0);
+}
+
+static int
+zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp)
+{
+ uint64_t blk, off;
+ int err;
+ dmu_buf_t *db;
+ int bs = FZAP_BLOCK_SHIFT(zap);
+
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+
+ blk = idx >> (bs-3);
+ off = idx & ((1<<(bs-3))-1);
+
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (tbl->zt_blk + blk) << bs, FTAG, &db);
+ if (err)
+ return (err);
+ *valp = ((uint64_t *)db->db_data)[off];
+ dmu_buf_rele(db, FTAG);
+
+ if (tbl->zt_nextblk != 0) {
+ /*
+ * read the nextblk for the sake of i/o error checking,
+ * so that zap_table_load() will catch errors for
+ * zap_table_store.
+ */
+ blk = (idx*2) >> (bs-3);
+
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (tbl->zt_nextblk + blk) << bs, FTAG, &db);
+ dmu_buf_rele(db, FTAG);
+ }
+ return (err);
+}
+
+/*
+ * Routines for growing the ptrtbl.
+ */
+
+static void
+zap_ptrtbl_transfer(const uint64_t *src, uint64_t *dst, int n)
+{
+ int i;
+ for (i = 0; i < n; i++) {
+ uint64_t lb = src[i];
+ dst[2*i+0] = lb;
+ dst[2*i+1] = lb;
+ }
+}
+
+static int
+zap_grow_ptrtbl(zap_t *zap, dmu_tx_t *tx)
+{
+ /* In case things go horribly wrong. */
+ if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift >= ZAP_HASHBITS-2)
+ return (ENOSPC);
+
+ if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) {
+ /*
+ * We are outgrowing the "embedded" ptrtbl (the one
+ * stored in the header block). Give it its own entire
+ * block, which will double the size of the ptrtbl.
+ */
+ uint64_t newblk;
+ dmu_buf_t *db_new;
+ int err;
+
+ ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==,
+ ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
+ ASSERT3U(zap->zap_f.zap_phys->zap_ptrtbl.zt_blk, ==, 0);
+
+ newblk = zap_allocate_blocks(zap, 1);
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ newblk << FZAP_BLOCK_SHIFT(zap), FTAG, &db_new);
+ if (err)
+ return (err);
+ dmu_buf_will_dirty(db_new, tx);
+ zap_ptrtbl_transfer(&ZAP_EMBEDDED_PTRTBL_ENT(zap, 0),
+ db_new->db_data, 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
+ dmu_buf_rele(db_new, FTAG);
+
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_blk = newblk;
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks = 1;
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_shift++;
+
+ ASSERT3U(1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift, ==,
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks <<
+ (FZAP_BLOCK_SHIFT(zap)-3));
+
+ return (0);
+ } else {
+ return (zap_table_grow(zap, &zap->zap_f.zap_phys->zap_ptrtbl,
+ zap_ptrtbl_transfer, tx));
+ }
+}
+
+static void
+zap_increment_num_entries(zap_t *zap, int delta, dmu_tx_t *tx)
+{
+ dmu_buf_will_dirty(zap->zap_dbuf, tx);
+ mutex_enter(&zap->zap_f.zap_num_entries_mtx);
+ ASSERT(delta > 0 || zap->zap_f.zap_phys->zap_num_entries >= -delta);
+ zap->zap_f.zap_phys->zap_num_entries += delta;
+ mutex_exit(&zap->zap_f.zap_num_entries_mtx);
+}
+
+static uint64_t
+zap_allocate_blocks(zap_t *zap, int nblocks)
+{
+ uint64_t newblk;
+ ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
+ newblk = zap->zap_f.zap_phys->zap_freeblk;
+ zap->zap_f.zap_phys->zap_freeblk += nblocks;
+ return (newblk);
+}
+
+static zap_leaf_t *
+zap_create_leaf(zap_t *zap, dmu_tx_t *tx)
+{
+ void *winner;
+ zap_leaf_t *l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
+
+ ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
+
+ rw_init(&l->l_rwlock, NULL, RW_DEFAULT, 0);
+ rw_enter(&l->l_rwlock, RW_WRITER);
+ l->l_blkid = zap_allocate_blocks(zap, 1);
+ l->l_dbuf = NULL;
+ l->l_phys = NULL;
+
+ VERIFY(0 == dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ l->l_blkid << FZAP_BLOCK_SHIFT(zap), NULL, &l->l_dbuf));
+ winner = dmu_buf_set_user(l->l_dbuf, l, &l->l_phys, zap_leaf_pageout);
+ ASSERT(winner == NULL);
+ dmu_buf_will_dirty(l->l_dbuf, tx);
+
+ zap_leaf_init(l);
+
+ zap->zap_f.zap_phys->zap_num_leafs++;
+
+ return (l);
+}
+
+int
+fzap_count(zap_t *zap, uint64_t *count)
+{
+ ASSERT(!zap->zap_ismicro);
+ mutex_enter(&zap->zap_f.zap_num_entries_mtx); /* unnecessary */
+ *count = zap->zap_f.zap_phys->zap_num_entries;
+ mutex_exit(&zap->zap_f.zap_num_entries_mtx);
+ return (0);
+}
+
+/*
+ * Routines for obtaining zap_leaf_t's
+ */
+
+void
+zap_put_leaf(zap_leaf_t *l)
+{
+ rw_exit(&l->l_rwlock);
+ dmu_buf_rele(l->l_dbuf, NULL);
+}
+
+_NOTE(ARGSUSED(0))
+static void
+zap_leaf_pageout(dmu_buf_t *db, void *vl)
+{
+ zap_leaf_t *l = vl;
+
+ rw_destroy(&l->l_rwlock);
+ kmem_free(l, sizeof (zap_leaf_t));
+}
+
+static zap_leaf_t *
+zap_open_leaf(uint64_t blkid, dmu_buf_t *db)
+{
+ zap_leaf_t *l, *winner;
+
+ ASSERT(blkid != 0);
+
+ l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
+ rw_init(&l->l_rwlock, NULL, RW_DEFAULT, 0);
+ rw_enter(&l->l_rwlock, RW_WRITER);
+ l->l_blkid = blkid;
+ l->l_bs = highbit(db->db_size)-1;
+ l->l_dbuf = db;
+ l->l_phys = NULL;
+
+ winner = dmu_buf_set_user(db, l, &l->l_phys, zap_leaf_pageout);
+
+ rw_exit(&l->l_rwlock);
+ if (winner != NULL) {
+ /* someone else set it first */
+ zap_leaf_pageout(NULL, l);
+ l = winner;
+ }
+
+ /*
+ * lhr_pad was previously used for the next leaf in the leaf
+ * chain. There should be no chained leafs (as we have removed
+ * support for them).
+ */
+ ASSERT3U(l->l_phys->l_hdr.lh_pad1, ==, 0);
+
+ /*
+ * There should be more hash entries than there can be
+ * chunks to put in the hash table
+ */
+ ASSERT3U(ZAP_LEAF_HASH_NUMENTRIES(l), >, ZAP_LEAF_NUMCHUNKS(l) / 3);
+
+ /* The chunks should begin at the end of the hash table */
+ ASSERT3P(&ZAP_LEAF_CHUNK(l, 0), ==,
+ &l->l_phys->l_hash[ZAP_LEAF_HASH_NUMENTRIES(l)]);
+
+ /* The chunks should end at the end of the block */
+ ASSERT3U((uintptr_t)&ZAP_LEAF_CHUNK(l, ZAP_LEAF_NUMCHUNKS(l)) -
+ (uintptr_t)l->l_phys, ==, l->l_dbuf->db_size);
+
+ return (l);
+}
+
+static int
+zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt,
+ zap_leaf_t **lp)
+{
+ dmu_buf_t *db;
+ zap_leaf_t *l;
+ int bs = FZAP_BLOCK_SHIFT(zap);
+ int err;
+
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ blkid << bs, NULL, &db);
+ if (err)
+ return (err);
+
+ ASSERT3U(db->db_object, ==, zap->zap_object);
+ ASSERT3U(db->db_offset, ==, blkid << bs);
+ ASSERT3U(db->db_size, ==, 1 << bs);
+ ASSERT(blkid != 0);
+
+ l = dmu_buf_get_user(db);
+
+ if (l == NULL)
+ l = zap_open_leaf(blkid, db);
+
+ rw_enter(&l->l_rwlock, lt);
+ /*
+ * Must lock before dirtying, otherwise l->l_phys could change,
+ * causing ASSERT below to fail.
+ */
+ if (lt == RW_WRITER)
+ dmu_buf_will_dirty(db, tx);
+ ASSERT3U(l->l_blkid, ==, blkid);
+ ASSERT3P(l->l_dbuf, ==, db);
+ ASSERT3P(l->l_phys, ==, l->l_dbuf->db_data);
+ ASSERT3U(l->l_phys->l_hdr.lh_block_type, ==, ZBT_LEAF);
+ ASSERT3U(l->l_phys->l_hdr.lh_magic, ==, ZAP_LEAF_MAGIC);
+
+ *lp = l;
+ return (0);
+}
+
+static int
+zap_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t *valp)
+{
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+
+ if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) {
+ ASSERT3U(idx, <,
+ (1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift));
+ *valp = ZAP_EMBEDDED_PTRTBL_ENT(zap, idx);
+ return (0);
+ } else {
+ return (zap_table_load(zap, &zap->zap_f.zap_phys->zap_ptrtbl,
+ idx, valp));
+ }
+}
+
+static int
+zap_set_idx_to_blk(zap_t *zap, uint64_t idx, uint64_t blk, dmu_tx_t *tx)
+{
+ ASSERT(tx != NULL);
+ ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
+
+ if (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk == 0) {
+ ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) = blk;
+ return (0);
+ } else {
+ return (zap_table_store(zap, &zap->zap_f.zap_phys->zap_ptrtbl,
+ idx, blk, tx));
+ }
+}
+
+static int
+zap_deref_leaf(zap_t *zap, uint64_t h, dmu_tx_t *tx, krw_t lt, zap_leaf_t **lp)
+{
+ uint64_t idx, blk;
+ int err;
+
+ ASSERT(zap->zap_dbuf == NULL ||
+ zap->zap_f.zap_phys == zap->zap_dbuf->db_data);
+ ASSERT3U(zap->zap_f.zap_phys->zap_magic, ==, ZAP_MAGIC);
+ idx = ZAP_HASH_IDX(h, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift);
+ err = zap_idx_to_blk(zap, idx, &blk);
+ if (err != 0)
+ return (err);
+ err = zap_get_leaf_byblk(zap, blk, tx, lt, lp);
+
+ ASSERT(err || ZAP_HASH_IDX(h, (*lp)->l_phys->l_hdr.lh_prefix_len) ==
+ (*lp)->l_phys->l_hdr.lh_prefix);
+ return (err);
+}
+
+static int
+zap_expand_leaf(zap_t *zap, zap_leaf_t *l, uint64_t hash, dmu_tx_t *tx,
+ zap_leaf_t **lp)
+{
+ zap_leaf_t *nl;
+ int prefix_diff, i, err;
+ uint64_t sibling;
+ int old_prefix_len = l->l_phys->l_hdr.lh_prefix_len;
+
+ ASSERT3U(old_prefix_len, <=, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift);
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+
+ ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
+ l->l_phys->l_hdr.lh_prefix);
+
+ if (zap_tryupgradedir(zap, tx) == 0 ||
+ old_prefix_len == zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) {
+ /* We failed to upgrade, or need to grow the pointer table */
+ objset_t *os = zap->zap_objset;
+ uint64_t object = zap->zap_object;
+
+ zap_put_leaf(l);
+ zap_unlockdir(zap);
+ err = zap_lockdir(os, object, tx, RW_WRITER, FALSE, &zap);
+ if (err)
+ return (err);
+ ASSERT(!zap->zap_ismicro);
+
+ while (old_prefix_len ==
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_shift) {
+ err = zap_grow_ptrtbl(zap, tx);
+ if (err)
+ return (err);
+ }
+
+ err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
+ if (err)
+ return (err);
+
+ if (l->l_phys->l_hdr.lh_prefix_len != old_prefix_len) {
+ /* it split while our locks were down */
+ *lp = l;
+ return (0);
+ }
+ }
+ ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
+ ASSERT3U(old_prefix_len, <, zap->zap_f.zap_phys->zap_ptrtbl.zt_shift);
+ ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
+ l->l_phys->l_hdr.lh_prefix);
+
+ prefix_diff = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift -
+ (old_prefix_len + 1);
+ sibling = (ZAP_HASH_IDX(hash, old_prefix_len + 1) | 1) << prefix_diff;
+
+ /* check for i/o errors before doing zap_leaf_split */
+ for (i = 0; i < (1ULL<<prefix_diff); i++) {
+ uint64_t blk;
+ err = zap_idx_to_blk(zap, sibling+i, &blk);
+ if (err)
+ return (err);
+ ASSERT3U(blk, ==, l->l_blkid);
+ }
+
+ nl = zap_create_leaf(zap, tx);
+ zap_leaf_split(l, nl);
+
+ /* set sibling pointers */
+ for (i = 0; i < (1ULL<<prefix_diff); i++) {
+ err = zap_set_idx_to_blk(zap, sibling+i, nl->l_blkid, tx);
+ ASSERT3U(err, ==, 0); /* we checked for i/o errors above */
+ }
+
+ if (hash & (1ULL << (64 - l->l_phys->l_hdr.lh_prefix_len))) {
+ /* we want the sibling */
+ zap_put_leaf(l);
+ *lp = nl;
+ } else {
+ zap_put_leaf(nl);
+ *lp = l;
+ }
+
+ return (0);
+}
+
+static void
+zap_put_leaf_maybe_grow_ptrtbl(zap_t *zap, zap_leaf_t *l, dmu_tx_t *tx)
+{
+ int shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift;
+ int leaffull = (l->l_phys->l_hdr.lh_prefix_len == shift &&
+ l->l_phys->l_hdr.lh_nfree < ZAP_LEAF_LOW_WATER);
+
+ zap_put_leaf(l);
+
+ if (leaffull || zap->zap_f.zap_phys->zap_ptrtbl.zt_nextblk) {
+ int err;
+
+ /*
+ * We are in the middle of growing the pointer table, or
+ * this leaf will soon make us grow it.
+ */
+ if (zap_tryupgradedir(zap, tx) == 0) {
+ objset_t *os = zap->zap_objset;
+ uint64_t zapobj = zap->zap_object;
+
+ zap_unlockdir(zap);
+ err = zap_lockdir(os, zapobj, tx,
+ RW_WRITER, FALSE, &zap);
+ if (err)
+ return;
+ }
+
+ /* could have finished growing while our locks were down */
+ if (zap->zap_f.zap_phys->zap_ptrtbl.zt_shift == shift)
+ (void) zap_grow_ptrtbl(zap, tx);
+ }
+}
+
+
+static int
+fzap_checksize(const char *name, uint64_t integer_size, uint64_t num_integers)
+{
+ if (name && strlen(name) > ZAP_MAXNAMELEN)
+ return (E2BIG);
+
+ /* Only integer sizes supported by C */
+ switch (integer_size) {
+ case 1:
+ case 2:
+ case 4:
+ case 8:
+ break;
+ default:
+ return (EINVAL);
+ }
+
+ if (integer_size * num_integers > ZAP_MAXVALUELEN)
+ return (E2BIG);
+
+ return (0);
+}
+
+/*
+ * Routines for maniplulating attributes.
+ */
+int
+fzap_lookup(zap_t *zap, const char *name,
+ uint64_t integer_size, uint64_t num_integers, void *buf)
+{
+ zap_leaf_t *l;
+ int err;
+ uint64_t hash;
+ zap_entry_handle_t zeh;
+
+ err = fzap_checksize(name, integer_size, num_integers);
+ if (err != 0)
+ return (err);
+
+ hash = zap_hash(zap, name);
+ err = zap_deref_leaf(zap, hash, NULL, RW_READER, &l);
+ if (err != 0)
+ return (err);
+ err = zap_leaf_lookup(l, name, hash, &zeh);
+ if (err == 0)
+ err = zap_entry_read(&zeh, integer_size, num_integers, buf);
+
+ zap_put_leaf(l);
+ return (err);
+}
+
+int
+fzap_add_cd(zap_t *zap, const char *name,
+ uint64_t integer_size, uint64_t num_integers,
+ const void *val, uint32_t cd, dmu_tx_t *tx)
+{
+ zap_leaf_t *l;
+ uint64_t hash;
+ int err;
+ zap_entry_handle_t zeh;
+
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+ ASSERT(!zap->zap_ismicro);
+ ASSERT(fzap_checksize(name, integer_size, num_integers) == 0);
+
+ hash = zap_hash(zap, name);
+ err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
+ if (err != 0)
+ return (err);
+retry:
+ err = zap_leaf_lookup(l, name, hash, &zeh);
+ if (err == 0) {
+ err = EEXIST;
+ goto out;
+ }
+ if (err != ENOENT)
+ goto out;
+
+ err = zap_entry_create(l, name, hash, cd,
+ integer_size, num_integers, val, &zeh);
+
+ if (err == 0) {
+ zap_increment_num_entries(zap, 1, tx);
+ } else if (err == EAGAIN) {
+ err = zap_expand_leaf(zap, l, hash, tx, &l);
+ if (err == 0)
+ goto retry;
+ }
+
+out:
+ zap_put_leaf_maybe_grow_ptrtbl(zap, l, tx);
+ return (err);
+}
+
+int
+fzap_add(zap_t *zap, const char *name,
+ uint64_t integer_size, uint64_t num_integers,
+ const void *val, dmu_tx_t *tx)
+{
+ int err = fzap_checksize(name, integer_size, num_integers);
+ if (err != 0)
+ return (err);
+
+ return (fzap_add_cd(zap, name, integer_size, num_integers,
+ val, ZAP_MAXCD, tx));
+}
+
+int
+fzap_update(zap_t *zap, const char *name,
+ int integer_size, uint64_t num_integers, const void *val, dmu_tx_t *tx)
+{
+ zap_leaf_t *l;
+ uint64_t hash;
+ int err, create;
+ zap_entry_handle_t zeh;
+
+ ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
+ err = fzap_checksize(name, integer_size, num_integers);
+ if (err != 0)
+ return (err);
+
+ hash = zap_hash(zap, name);
+ err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
+ if (err != 0)
+ return (err);
+retry:
+ err = zap_leaf_lookup(l, name, hash, &zeh);
+ create = (err == ENOENT);
+ ASSERT(err == 0 || err == ENOENT);
+
+ /* XXX If this leaf is chained, split it if we can. */
+
+ if (create) {
+ err = zap_entry_create(l, name, hash, ZAP_MAXCD,
+ integer_size, num_integers, val, &zeh);
+ if (err == 0)
+ zap_increment_num_entries(zap, 1, tx);
+ } else {
+ err = zap_entry_update(&zeh, integer_size, num_integers, val);
+ }
+
+ if (err == EAGAIN) {
+ err = zap_expand_leaf(zap, l, hash, tx, &l);
+ if (err == 0)
+ goto retry;
+ }
+
+ zap_put_leaf_maybe_grow_ptrtbl(zap, l, tx);
+ return (err);
+}
+
+int
+fzap_length(zap_t *zap, const char *name,
+ uint64_t *integer_size, uint64_t *num_integers)
+{
+ zap_leaf_t *l;
+ int err;
+ uint64_t hash;
+ zap_entry_handle_t zeh;
+
+ hash = zap_hash(zap, name);
+ err = zap_deref_leaf(zap, hash, NULL, RW_READER, &l);
+ if (err != 0)
+ return (err);
+ err = zap_leaf_lookup(l, name, hash, &zeh);
+ if (err != 0)
+ goto out;
+
+ if (integer_size)
+ *integer_size = zeh.zeh_integer_size;
+ if (num_integers)
+ *num_integers = zeh.zeh_num_integers;
+out:
+ zap_put_leaf(l);
+ return (err);
+}
+
+int
+fzap_remove(zap_t *zap, const char *name, dmu_tx_t *tx)
+{
+ zap_leaf_t *l;
+ uint64_t hash;
+ int err;
+ zap_entry_handle_t zeh;
+
+ hash = zap_hash(zap, name);
+ err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
+ if (err != 0)
+ return (err);
+ err = zap_leaf_lookup(l, name, hash, &zeh);
+ if (err == 0) {
+ zap_entry_remove(&zeh);
+ zap_increment_num_entries(zap, -1, tx);
+ }
+ zap_put_leaf(l);
+ dprintf("fzap_remove: ds=%p obj=%llu name=%s err=%d\n",
+ zap->zap_objset, zap->zap_object, name, err);
+ return (err);
+}
+
+int
+zap_value_search(objset_t *os, uint64_t zapobj, uint64_t value, char *name)
+{
+ zap_cursor_t zc;
+ zap_attribute_t *za;
+ int err;
+
+ za = kmem_alloc(sizeof (zap_attribute_t), KM_SLEEP);
+ for (zap_cursor_init(&zc, os, zapobj);
+ (err = zap_cursor_retrieve(&zc, za)) == 0;
+ zap_cursor_advance(&zc)) {
+ if (za->za_first_integer == value) {
+ (void) strcpy(name, za->za_name);
+ break;
+ }
+ }
+ zap_cursor_fini(&zc);
+ kmem_free(za, sizeof (zap_attribute_t));
+ return (err);
+}
+
+
+/*
+ * Routines for iterating over the attributes.
+ */
+
+int
+fzap_cursor_retrieve(zap_t *zap, zap_cursor_t *zc, zap_attribute_t *za)
+{
+ int err = ENOENT;
+ zap_entry_handle_t zeh;
+ zap_leaf_t *l;
+
+ /* retrieve the next entry at or after zc_hash/zc_cd */
+ /* if no entry, return ENOENT */
+
+ if (zc->zc_leaf &&
+ (ZAP_HASH_IDX(zc->zc_hash,
+ zc->zc_leaf->l_phys->l_hdr.lh_prefix_len) !=
+ zc->zc_leaf->l_phys->l_hdr.lh_prefix)) {
+ rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
+ zap_put_leaf(zc->zc_leaf);
+ zc->zc_leaf = NULL;
+ }
+
+again:
+ if (zc->zc_leaf == NULL) {
+ err = zap_deref_leaf(zap, zc->zc_hash, NULL, RW_READER,
+ &zc->zc_leaf);
+ if (err != 0)
+ return (err);
+ } else {
+ rw_enter(&zc->zc_leaf->l_rwlock, RW_READER);
+ }
+ l = zc->zc_leaf;
+
+ err = zap_leaf_lookup_closest(l, zc->zc_hash, zc->zc_cd, &zeh);
+
+ if (err == ENOENT) {
+ uint64_t nocare =
+ (1ULL << (64 - l->l_phys->l_hdr.lh_prefix_len)) - 1;
+ zc->zc_hash = (zc->zc_hash & ~nocare) + nocare + 1;
+ zc->zc_cd = 0;
+ if (l->l_phys->l_hdr.lh_prefix_len == 0 || zc->zc_hash == 0) {
+ zc->zc_hash = -1ULL;
+ } else {
+ zap_put_leaf(zc->zc_leaf);
+ zc->zc_leaf = NULL;
+ goto again;
+ }
+ }
+
+ if (err == 0) {
+ zc->zc_hash = zeh.zeh_hash;
+ zc->zc_cd = zeh.zeh_cd;
+ za->za_integer_length = zeh.zeh_integer_size;
+ za->za_num_integers = zeh.zeh_num_integers;
+ if (zeh.zeh_num_integers == 0) {
+ za->za_first_integer = 0;
+ } else {
+ err = zap_entry_read(&zeh, 8, 1, &za->za_first_integer);
+ ASSERT(err == 0 || err == EOVERFLOW);
+ }
+ err = zap_entry_read_name(&zeh,
+ sizeof (za->za_name), za->za_name);
+ ASSERT(err == 0);
+ }
+ rw_exit(&zc->zc_leaf->l_rwlock);
+ return (err);
+}
+
+
+static void
+zap_stats_ptrtbl(zap_t *zap, uint64_t *tbl, int len, zap_stats_t *zs)
+{
+ int i, err;
+ uint64_t lastblk = 0;
+
+ /*
+ * NB: if a leaf has more pointers than an entire ptrtbl block
+ * can hold, then it'll be accounted for more than once, since
+ * we won't have lastblk.
+ */
+ for (i = 0; i < len; i++) {
+ zap_leaf_t *l;
+
+ if (tbl[i] == lastblk)
+ continue;
+ lastblk = tbl[i];
+
+ err = zap_get_leaf_byblk(zap, tbl[i], NULL, RW_READER, &l);
+ if (err == 0) {
+ zap_leaf_stats(zap, l, zs);
+ zap_put_leaf(l);
+ }
+ }
+}
+
+void
+fzap_get_stats(zap_t *zap, zap_stats_t *zs)
+{
+ int bs = FZAP_BLOCK_SHIFT(zap);
+ zs->zs_blocksize = 1ULL << bs;
+
+ /*
+ * Set zap_phys_t fields
+ */
+ zs->zs_num_leafs = zap->zap_f.zap_phys->zap_num_leafs;
+ zs->zs_num_entries = zap->zap_f.zap_phys->zap_num_entries;
+ zs->zs_num_blocks = zap->zap_f.zap_phys->zap_freeblk;
+ zs->zs_block_type = zap->zap_f.zap_phys->zap_block_type;
+ zs->zs_magic = zap->zap_f.zap_phys->zap_magic;
+ zs->zs_salt = zap->zap_f.zap_phys->zap_salt;
+
+ /*
+ * Set zap_ptrtbl fields
+ */
+ zs->zs_ptrtbl_len = 1ULL << zap->zap_f.zap_phys->zap_ptrtbl.zt_shift;
+ zs->zs_ptrtbl_nextblk = zap->zap_f.zap_phys->zap_ptrtbl.zt_nextblk;
+ zs->zs_ptrtbl_blks_copied =
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_blks_copied;
+ zs->zs_ptrtbl_zt_blk = zap->zap_f.zap_phys->zap_ptrtbl.zt_blk;
+ zs->zs_ptrtbl_zt_numblks = zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks;
+ zs->zs_ptrtbl_zt_shift = zap->zap_f.zap_phys->zap_ptrtbl.zt_shift;
+
+ if (zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks == 0) {
+ /* the ptrtbl is entirely in the header block. */
+ zap_stats_ptrtbl(zap, &ZAP_EMBEDDED_PTRTBL_ENT(zap, 0),
+ 1 << ZAP_EMBEDDED_PTRTBL_SHIFT(zap), zs);
+ } else {
+ int b;
+
+ dmu_prefetch(zap->zap_objset, zap->zap_object,
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_blk << bs,
+ zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks << bs);
+
+ for (b = 0; b < zap->zap_f.zap_phys->zap_ptrtbl.zt_numblks;
+ b++) {
+ dmu_buf_t *db;
+ int err;
+
+ err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
+ (zap->zap_f.zap_phys->zap_ptrtbl.zt_blk + b) << bs,
+ FTAG, &db);
+ if (err == 0) {
+ zap_stats_ptrtbl(zap, db->db_data,
+ 1<<(bs-3), zs);
+ dmu_buf_rele(db, FTAG);
+ }
+ }
+ }
+}
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