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|
/*
* 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 https://opensource.org/licenses/CDDL-1.0.
* 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 (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2018 by Delphix. All rights reserved.
* Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
*/
/*
* 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/zfs_znode.h>
#include <sys/fs/zfs.h>
#include <sys/zap.h>
#include <sys/zap_impl.h>
#include <sys/zap_leaf.h>
/*
* If zap_iterate_prefetch is set, we will prefetch the entire ZAP object
* (all leaf blocks) when we start iterating over it.
*
* For zap_cursor_init(), the callers all intend to iterate through all the
* entries. There are a few cases where an error (typically i/o error) could
* cause it to bail out early.
*
* For zap_cursor_init_serialized(), there are callers that do the iteration
* outside of ZFS. Typically they would iterate over everything, but we
* don't have control of that. E.g. zfs_ioc_snapshot_list_next(),
* zcp_snapshots_iter(), and other iterators over things in the MOS - these
* are called by /sbin/zfs and channel programs. The other example is
* zfs_readdir() which iterates over directory entries for the getdents()
* syscall. /sbin/ls iterates to the end (unless it receives a signal), but
* userland doesn't have to.
*
* Given that the ZAP entries aren't returned in a specific order, the only
* legitimate use cases for partial iteration would be:
*
* 1. Pagination: e.g. you only want to display 100 entries at a time, so you
* get the first 100 and then wait for the user to hit "next page", which
* they may never do).
*
* 2. You want to know if there are more than X entries, without relying on
* the zfs-specific implementation of the directory's st_size (which is
* the number of entries).
*/
static int zap_iterate_prefetch = B_TRUE;
int fzap_default_block_shift = 14; /* 16k blocksize */
static uint64_t zap_allocate_blocks(zap_t *zap, int nblocks);
void
fzap_byteswap(void *vbuf, size_t size)
{
uint64_t 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, zap_flags_t flags)
{
ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
zap->zap_ismicro = FALSE;
zap->zap_dbu.dbu_evict_func_sync = zap_evict_sync;
zap->zap_dbu.dbu_evict_func_async = NULL;
mutex_init(&zap->zap_f.zap_num_entries_mtx, 0, MUTEX_DEFAULT, 0);
zap->zap_f.zap_block_shift = highbit64(zap->zap_dbuf->db_size) - 1;
zap_phys_t *zp = zap_f_phys(zap);
/*
* explicitly zero it since it might be coming from an
* initialized microzap
*/
memset(zap->zap_dbuf->db_data, 0, 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;
zp->zap_normflags = zap->zap_normflags;
zp->zap_flags = flags;
/* block 1 will be the first leaf */
for (int i = 0; i < (1<<zp->zap_ptrtbl.zt_shift); i++)
ZAP_EMBEDDED_PTRTBL_ENT(zap, i) = 1;
/*
* set up block 1 - the first leaf
*/
dmu_buf_t *db;
VERIFY0(dmu_buf_hold(zap->zap_objset, zap->zap_object,
1<<FZAP_BLOCK_SHIFT(zap), FTAG, &db, DMU_READ_NO_PREFETCH));
dmu_buf_will_dirty(db, tx);
zap_leaf_t *l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
l->l_dbuf = db;
zap_leaf_init(l, zp->zap_normflags != 0);
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 newblk;
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;
ASSERT0(tbl->zt_blks_copied);
dmu_prefetch(zap->zap_objset, zap->zap_object, 0,
tbl->zt_blk << bs, tbl->zt_numblks << bs,
ZIO_PRIORITY_SYNC_READ);
}
/*
* Copy the ptrtbl from the old to new location.
*/
uint64_t b = tbl->zt_blks_copied;
dmu_buf_t *db_old;
int err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
(tbl->zt_blk + b) << bs, FTAG, &db_old, DMU_READ_NO_PREFETCH);
if (err != 0)
return (err);
/* first half of entries in old[b] go to new[2*b+0] */
dmu_buf_t *db_new;
VERIFY0(dmu_buf_hold(zap->zap_objset, zap->zap_object,
(newblk + 2*b+0) << bs, FTAG, &db_new, DMU_READ_NO_PREFETCH));
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] */
VERIFY0(dmu_buf_hold(zap->zap_objset, zap->zap_object,
(newblk + 2*b+1) << bs, FTAG, &db_new, DMU_READ_NO_PREFETCH));
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",
(u_longlong_t)tbl->zt_blks_copied,
(u_longlong_t)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 (%uk entries)\n",
(u_longlong_t)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 bs = FZAP_BLOCK_SHIFT(zap);
ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
ASSERT(tbl->zt_blk != 0);
dprintf("storing %llx at index %llx\n", (u_longlong_t)val,
(u_longlong_t)idx);
uint64_t blk = idx >> (bs-3);
uint64_t off = idx & ((1<<(bs-3))-1);
dmu_buf_t *db;
int err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
(tbl->zt_blk + blk) << bs, FTAG, &db, DMU_READ_NO_PREFETCH);
if (err != 0)
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,
DMU_READ_NO_PREFETCH);
if (err != 0) {
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)
{
int bs = FZAP_BLOCK_SHIFT(zap);
ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
uint64_t blk = idx >> (bs-3);
uint64_t off = idx & ((1<<(bs-3))-1);
/*
* Note: this is equivalent to dmu_buf_hold(), but we use
* _dnode_enter / _by_dnode because it's faster because we don't
* have to hold the dnode.
*/
dnode_t *dn = dmu_buf_dnode_enter(zap->zap_dbuf);
dmu_buf_t *db;
int err = dmu_buf_hold_by_dnode(dn,
(tbl->zt_blk + blk) << bs, FTAG, &db, DMU_READ_NO_PREFETCH);
dmu_buf_dnode_exit(zap->zap_dbuf);
if (err != 0)
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);
dn = dmu_buf_dnode_enter(zap->zap_dbuf);
err = dmu_buf_hold_by_dnode(dn,
(tbl->zt_nextblk + blk) << bs, FTAG, &db,
DMU_READ_NO_PREFETCH);
dmu_buf_dnode_exit(zap->zap_dbuf);
if (err == 0)
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)
{
for (int 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)
{
/*
* The pointer table should never use more hash bits than we
* have (otherwise we'd be using useless zero bits to index it).
* If we are within 2 bits of running out, stop growing, since
* this is already an aberrant condition.
*/
if (zap_f_phys(zap)->zap_ptrtbl.zt_shift >= zap_hashbits(zap) - 2)
return (SET_ERROR(ENOSPC));
if (zap_f_phys(zap)->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.
*/
ASSERT3U(zap_f_phys(zap)->zap_ptrtbl.zt_shift, ==,
ZAP_EMBEDDED_PTRTBL_SHIFT(zap));
ASSERT0(zap_f_phys(zap)->zap_ptrtbl.zt_blk);
uint64_t newblk = zap_allocate_blocks(zap, 1);
dmu_buf_t *db_new;
int err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
newblk << FZAP_BLOCK_SHIFT(zap), FTAG, &db_new,
DMU_READ_NO_PREFETCH);
if (err != 0)
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_f_phys(zap)->zap_ptrtbl.zt_blk = newblk;
zap_f_phys(zap)->zap_ptrtbl.zt_numblks = 1;
zap_f_phys(zap)->zap_ptrtbl.zt_shift++;
ASSERT3U(1ULL << zap_f_phys(zap)->zap_ptrtbl.zt_shift, ==,
zap_f_phys(zap)->zap_ptrtbl.zt_numblks <<
(FZAP_BLOCK_SHIFT(zap)-3));
return (0);
} else {
return (zap_table_grow(zap, &zap_f_phys(zap)->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_f_phys(zap)->zap_num_entries >= -delta);
zap_f_phys(zap)->zap_num_entries += delta;
mutex_exit(&zap->zap_f.zap_num_entries_mtx);
}
static uint64_t
zap_allocate_blocks(zap_t *zap, int nblocks)
{
ASSERT(RW_WRITE_HELD(&zap->zap_rwlock));
uint64_t newblk = zap_f_phys(zap)->zap_freeblk;
zap_f_phys(zap)->zap_freeblk += nblocks;
return (newblk);
}
static void
zap_leaf_evict_sync(void *dbu)
{
zap_leaf_t *l = dbu;
rw_destroy(&l->l_rwlock);
kmem_free(l, sizeof (zap_leaf_t));
}
static zap_leaf_t *
zap_create_leaf(zap_t *zap, dmu_tx_t *tx)
{
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_NOLOCKDEP, NULL);
rw_enter(&l->l_rwlock, RW_WRITER);
l->l_blkid = zap_allocate_blocks(zap, 1);
l->l_dbuf = NULL;
VERIFY0(dmu_buf_hold(zap->zap_objset, zap->zap_object,
l->l_blkid << FZAP_BLOCK_SHIFT(zap), NULL, &l->l_dbuf,
DMU_READ_NO_PREFETCH));
dmu_buf_init_user(&l->l_dbu, zap_leaf_evict_sync, NULL, &l->l_dbuf);
VERIFY3P(NULL, ==, dmu_buf_set_user(l->l_dbuf, &l->l_dbu));
dmu_buf_will_dirty(l->l_dbuf, tx);
zap_leaf_init(l, zap->zap_normflags != 0);
zap_f_phys(zap)->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_f_phys(zap)->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);
}
static zap_leaf_t *
zap_open_leaf(uint64_t blkid, dmu_buf_t *db)
{
ASSERT(blkid != 0);
zap_leaf_t *l = kmem_zalloc(sizeof (zap_leaf_t), KM_SLEEP);
rw_init(&l->l_rwlock, NULL, RW_DEFAULT, NULL);
rw_enter(&l->l_rwlock, RW_WRITER);
l->l_blkid = blkid;
l->l_bs = highbit64(db->db_size) - 1;
l->l_dbuf = db;
dmu_buf_init_user(&l->l_dbu, zap_leaf_evict_sync, NULL, &l->l_dbuf);
zap_leaf_t *winner = dmu_buf_set_user(db, &l->l_dbu);
rw_exit(&l->l_rwlock);
if (winner != NULL) {
/* someone else set it first */
zap_leaf_evict_sync(&l->l_dbu);
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).
*/
ASSERT0(zap_leaf_phys(l)->l_hdr.lh_pad1);
/*
* 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), ==, (zap_leaf_chunk_t *)
&zap_leaf_phys(l)->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)zap_leaf_phys(l), ==, 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;
ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
/*
* If system crashed just after dmu_free_long_range in zfs_rmnode, we
* would be left with an empty xattr dir in delete queue. blkid=0
* would be passed in when doing zfs_purgedir. If that's the case we
* should just return immediately. The underlying objects should
* already be freed, so this should be perfectly fine.
*/
if (blkid == 0)
return (SET_ERROR(ENOENT));
int bs = FZAP_BLOCK_SHIFT(zap);
dnode_t *dn = dmu_buf_dnode_enter(zap->zap_dbuf);
int err = dmu_buf_hold_by_dnode(dn,
blkid << bs, NULL, &db, DMU_READ_NO_PREFETCH);
dmu_buf_dnode_exit(zap->zap_dbuf);
if (err != 0)
return (err);
ASSERT3U(db->db_object, ==, zap->zap_object);
ASSERT3U(db->db_offset, ==, blkid << bs);
ASSERT3U(db->db_size, ==, 1 << bs);
ASSERT(blkid != 0);
zap_leaf_t *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 zap_leaf_phys(l) 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);
ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_block_type, ==, ZBT_LEAF);
ASSERT3U(zap_leaf_phys(l)->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_f_phys(zap)->zap_ptrtbl.zt_numblks == 0) {
ASSERT3U(idx, <,
(1ULL << zap_f_phys(zap)->zap_ptrtbl.zt_shift));
*valp = ZAP_EMBEDDED_PTRTBL_ENT(zap, idx);
return (0);
} else {
return (zap_table_load(zap, &zap_f_phys(zap)->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_f_phys(zap)->zap_ptrtbl.zt_blk == 0) {
ZAP_EMBEDDED_PTRTBL_ENT(zap, idx) = blk;
return (0);
} else {
return (zap_table_store(zap, &zap_f_phys(zap)->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 blk;
ASSERT(zap->zap_dbuf == NULL ||
zap_f_phys(zap) == zap->zap_dbuf->db_data);
/* Reality check for corrupt zap objects (leaf or header). */
if ((zap_f_phys(zap)->zap_block_type != ZBT_LEAF &&
zap_f_phys(zap)->zap_block_type != ZBT_HEADER) ||
zap_f_phys(zap)->zap_magic != ZAP_MAGIC) {
return (SET_ERROR(EIO));
}
uint64_t idx = ZAP_HASH_IDX(h, zap_f_phys(zap)->zap_ptrtbl.zt_shift);
int 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, zap_leaf_phys(*lp)->l_hdr.lh_prefix_len) ==
zap_leaf_phys(*lp)->l_hdr.lh_prefix);
return (err);
}
static int
zap_expand_leaf(zap_name_t *zn, zap_leaf_t *l,
const void *tag, dmu_tx_t *tx, zap_leaf_t **lp)
{
zap_t *zap = zn->zn_zap;
uint64_t hash = zn->zn_hash;
int err;
int old_prefix_len = zap_leaf_phys(l)->l_hdr.lh_prefix_len;
ASSERT3U(old_prefix_len, <=, zap_f_phys(zap)->zap_ptrtbl.zt_shift);
ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
zap_leaf_phys(l)->l_hdr.lh_prefix);
if (zap_tryupgradedir(zap, tx) == 0 ||
old_prefix_len == zap_f_phys(zap)->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, tag);
err = zap_lockdir(os, object, tx, RW_WRITER,
FALSE, FALSE, tag, &zn->zn_zap);
zap = zn->zn_zap;
if (err != 0)
return (err);
ASSERT(!zap->zap_ismicro);
while (old_prefix_len ==
zap_f_phys(zap)->zap_ptrtbl.zt_shift) {
err = zap_grow_ptrtbl(zap, tx);
if (err != 0)
return (err);
}
err = zap_deref_leaf(zap, hash, tx, RW_WRITER, &l);
if (err != 0)
return (err);
if (zap_leaf_phys(l)->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_f_phys(zap)->zap_ptrtbl.zt_shift);
ASSERT3U(ZAP_HASH_IDX(hash, old_prefix_len), ==,
zap_leaf_phys(l)->l_hdr.lh_prefix);
int prefix_diff = zap_f_phys(zap)->zap_ptrtbl.zt_shift -
(old_prefix_len + 1);
uint64_t sibling =
(ZAP_HASH_IDX(hash, old_prefix_len + 1) | 1) << prefix_diff;
/* check for i/o errors before doing zap_leaf_split */
for (int i = 0; i < (1ULL << prefix_diff); i++) {
uint64_t blk;
err = zap_idx_to_blk(zap, sibling + i, &blk);
if (err != 0)
return (err);
ASSERT3U(blk, ==, l->l_blkid);
}
zap_leaf_t *nl = zap_create_leaf(zap, tx);
zap_leaf_split(l, nl, zap->zap_normflags != 0);
/* set sibling pointers */
for (int i = 0; i < (1ULL << prefix_diff); i++) {
err = zap_set_idx_to_blk(zap, sibling + i, nl->l_blkid, tx);
ASSERT0(err); /* we checked for i/o errors above */
}
ASSERT3U(zap_leaf_phys(l)->l_hdr.lh_prefix_len, >, 0);
if (hash & (1ULL << (64 - zap_leaf_phys(l)->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_name_t *zn, zap_leaf_t *l,
const void *tag, dmu_tx_t *tx)
{
zap_t *zap = zn->zn_zap;
int shift = zap_f_phys(zap)->zap_ptrtbl.zt_shift;
int leaffull = (zap_leaf_phys(l)->l_hdr.lh_prefix_len == shift &&
zap_leaf_phys(l)->l_hdr.lh_nfree < ZAP_LEAF_LOW_WATER);
zap_put_leaf(l);
if (leaffull || zap_f_phys(zap)->zap_ptrtbl.zt_nextblk) {
/*
* 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, tag);
int err = zap_lockdir(os, zapobj, tx,
RW_WRITER, FALSE, FALSE, tag, &zn->zn_zap);
zap = zn->zn_zap;
if (err != 0)
return;
}
/* could have finished growing while our locks were down */
if (zap_f_phys(zap)->zap_ptrtbl.zt_shift == shift)
(void) zap_grow_ptrtbl(zap, tx);
}
}
static int
fzap_checkname(zap_name_t *zn)
{
if (zn->zn_key_orig_numints * zn->zn_key_intlen > ZAP_MAXNAMELEN)
return (SET_ERROR(ENAMETOOLONG));
return (0);
}
static int
fzap_checksize(uint64_t integer_size, uint64_t num_integers)
{
/* Only integer sizes supported by C */
switch (integer_size) {
case 1:
case 2:
case 4:
case 8:
break;
default:
return (SET_ERROR(EINVAL));
}
if (integer_size * num_integers > ZAP_MAXVALUELEN)
return (SET_ERROR(E2BIG));
return (0);
}
static int
fzap_check(zap_name_t *zn, uint64_t integer_size, uint64_t num_integers)
{
int err = fzap_checkname(zn);
if (err != 0)
return (err);
return (fzap_checksize(integer_size, num_integers));
}
/*
* Routines for manipulating attributes.
*/
int
fzap_lookup(zap_name_t *zn,
uint64_t integer_size, uint64_t num_integers, void *buf,
char *realname, int rn_len, boolean_t *ncp)
{
zap_leaf_t *l;
zap_entry_handle_t zeh;
int err = fzap_checkname(zn);
if (err != 0)
return (err);
err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l);
if (err != 0)
return (err);
err = zap_leaf_lookup(l, zn, &zeh);
if (err == 0) {
if ((err = fzap_checksize(integer_size, num_integers)) != 0) {
zap_put_leaf(l);
return (err);
}
err = zap_entry_read(&zeh, integer_size, num_integers, buf);
(void) zap_entry_read_name(zn->zn_zap, &zeh, rn_len, realname);
if (ncp) {
*ncp = zap_entry_normalization_conflict(&zeh,
zn, NULL, zn->zn_zap);
}
}
zap_put_leaf(l);
return (err);
}
int
fzap_add_cd(zap_name_t *zn,
uint64_t integer_size, uint64_t num_integers,
const void *val, uint32_t cd, const void *tag, dmu_tx_t *tx)
{
zap_leaf_t *l;
int err;
zap_entry_handle_t zeh;
zap_t *zap = zn->zn_zap;
ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
ASSERT(!zap->zap_ismicro);
ASSERT(fzap_check(zn, integer_size, num_integers) == 0);
err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l);
if (err != 0)
return (err);
retry:
err = zap_leaf_lookup(l, zn, &zeh);
if (err == 0) {
err = SET_ERROR(EEXIST);
goto out;
}
if (err != ENOENT)
goto out;
err = zap_entry_create(l, zn, 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(zn, l, tag, tx, &l);
zap = zn->zn_zap; /* zap_expand_leaf() may change zap */
if (err == 0) {
goto retry;
} else if (err == ENOSPC) {
/*
* If we failed to expand the leaf, then bailout
* as there is no point trying
* zap_put_leaf_maybe_grow_ptrtbl().
*/
return (err);
}
}
out:
if (zap != NULL)
zap_put_leaf_maybe_grow_ptrtbl(zn, l, tag, tx);
return (err);
}
int
fzap_add(zap_name_t *zn,
uint64_t integer_size, uint64_t num_integers,
const void *val, const void *tag, dmu_tx_t *tx)
{
int err = fzap_check(zn, integer_size, num_integers);
if (err != 0)
return (err);
return (fzap_add_cd(zn, integer_size, num_integers,
val, ZAP_NEED_CD, tag, tx));
}
int
fzap_update(zap_name_t *zn,
int integer_size, uint64_t num_integers, const void *val,
const void *tag, dmu_tx_t *tx)
{
zap_leaf_t *l;
int err;
boolean_t create;
zap_entry_handle_t zeh;
zap_t *zap = zn->zn_zap;
ASSERT(RW_LOCK_HELD(&zap->zap_rwlock));
err = fzap_check(zn, integer_size, num_integers);
if (err != 0)
return (err);
err = zap_deref_leaf(zap, zn->zn_hash, tx, RW_WRITER, &l);
if (err != 0)
return (err);
retry:
err = zap_leaf_lookup(l, zn, &zeh);
create = (err == ENOENT);
ASSERT(err == 0 || err == ENOENT);
if (create) {
err = zap_entry_create(l, zn, ZAP_NEED_CD,
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(zn, l, tag, tx, &l);
zap = zn->zn_zap; /* zap_expand_leaf() may change zap */
if (err == 0)
goto retry;
}
if (zap != NULL)
zap_put_leaf_maybe_grow_ptrtbl(zn, l, tag, tx);
return (err);
}
int
fzap_length(zap_name_t *zn,
uint64_t *integer_size, uint64_t *num_integers)
{
zap_leaf_t *l;
int err;
zap_entry_handle_t zeh;
err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, NULL, RW_READER, &l);
if (err != 0)
return (err);
err = zap_leaf_lookup(l, zn, &zeh);
if (err != 0)
goto out;
if (integer_size != 0)
*integer_size = zeh.zeh_integer_size;
if (num_integers != 0)
*num_integers = zeh.zeh_num_integers;
out:
zap_put_leaf(l);
return (err);
}
int
fzap_remove(zap_name_t *zn, dmu_tx_t *tx)
{
zap_leaf_t *l;
int err;
zap_entry_handle_t zeh;
err = zap_deref_leaf(zn->zn_zap, zn->zn_hash, tx, RW_WRITER, &l);
if (err != 0)
return (err);
err = zap_leaf_lookup(l, zn, &zeh);
if (err == 0) {
zap_entry_remove(&zeh);
zap_increment_num_entries(zn->zn_zap, -1, tx);
}
zap_put_leaf(l);
return (err);
}
void
fzap_prefetch(zap_name_t *zn)
{
uint64_t blk;
zap_t *zap = zn->zn_zap;
uint64_t idx = ZAP_HASH_IDX(zn->zn_hash,
zap_f_phys(zap)->zap_ptrtbl.zt_shift);
if (zap_idx_to_blk(zap, idx, &blk) != 0)
return;
int bs = FZAP_BLOCK_SHIFT(zap);
dmu_prefetch(zap->zap_objset, zap->zap_object, 0, blk << bs, 1 << bs,
ZIO_PRIORITY_SYNC_READ);
}
/*
* Helper functions for consumers.
*/
uint64_t
zap_create_link(objset_t *os, dmu_object_type_t ot, uint64_t parent_obj,
const char *name, dmu_tx_t *tx)
{
return (zap_create_link_dnsize(os, ot, parent_obj, name, 0, tx));
}
uint64_t
zap_create_link_dnsize(objset_t *os, dmu_object_type_t ot, uint64_t parent_obj,
const char *name, int dnodesize, dmu_tx_t *tx)
{
uint64_t new_obj;
new_obj = zap_create_dnsize(os, ot, DMU_OT_NONE, 0, dnodesize, tx);
VERIFY(new_obj != 0);
VERIFY0(zap_add(os, parent_obj, name, sizeof (uint64_t), 1, &new_obj,
tx));
return (new_obj);
}
int
zap_value_search(objset_t *os, uint64_t zapobj, uint64_t value, uint64_t mask,
char *name)
{
zap_cursor_t zc;
int err;
if (mask == 0)
mask = -1ULL;
zap_attribute_t *za = kmem_alloc(sizeof (*za), 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 & mask) == (value & mask)) {
(void) strlcpy(name, za->za_name, MAXNAMELEN);
break;
}
}
zap_cursor_fini(&zc);
kmem_free(za, sizeof (*za));
return (err);
}
int
zap_join(objset_t *os, uint64_t fromobj, uint64_t intoobj, dmu_tx_t *tx)
{
zap_cursor_t zc;
int err = 0;
zap_attribute_t *za = kmem_alloc(sizeof (*za), KM_SLEEP);
for (zap_cursor_init(&zc, os, fromobj);
zap_cursor_retrieve(&zc, za) == 0;
(void) zap_cursor_advance(&zc)) {
if (za->za_integer_length != 8 || za->za_num_integers != 1) {
err = SET_ERROR(EINVAL);
break;
}
err = zap_add(os, intoobj, za->za_name,
8, 1, &za->za_first_integer, tx);
if (err != 0)
break;
}
zap_cursor_fini(&zc);
kmem_free(za, sizeof (*za));
return (err);
}
int
zap_join_key(objset_t *os, uint64_t fromobj, uint64_t intoobj,
uint64_t value, dmu_tx_t *tx)
{
zap_cursor_t zc;
int err = 0;
zap_attribute_t *za = kmem_alloc(sizeof (*za), KM_SLEEP);
for (zap_cursor_init(&zc, os, fromobj);
zap_cursor_retrieve(&zc, za) == 0;
(void) zap_cursor_advance(&zc)) {
if (za->za_integer_length != 8 || za->za_num_integers != 1) {
err = SET_ERROR(EINVAL);
break;
}
err = zap_add(os, intoobj, za->za_name,
8, 1, &value, tx);
if (err != 0)
break;
}
zap_cursor_fini(&zc);
kmem_free(za, sizeof (*za));
return (err);
}
int
zap_join_increment(objset_t *os, uint64_t fromobj, uint64_t intoobj,
dmu_tx_t *tx)
{
zap_cursor_t zc;
int err = 0;
zap_attribute_t *za = kmem_alloc(sizeof (*za), KM_SLEEP);
for (zap_cursor_init(&zc, os, fromobj);
zap_cursor_retrieve(&zc, za) == 0;
(void) zap_cursor_advance(&zc)) {
uint64_t delta = 0;
if (za->za_integer_length != 8 || za->za_num_integers != 1) {
err = SET_ERROR(EINVAL);
break;
}
err = zap_lookup(os, intoobj, za->za_name, 8, 1, &delta);
if (err != 0 && err != ENOENT)
break;
delta += za->za_first_integer;
err = zap_update(os, intoobj, za->za_name, 8, 1, &delta, tx);
if (err != 0)
break;
}
zap_cursor_fini(&zc);
kmem_free(za, sizeof (*za));
return (err);
}
int
zap_add_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
return (zap_add(os, obj, name, 8, 1, &value, tx));
}
int
zap_remove_int(objset_t *os, uint64_t obj, uint64_t value, dmu_tx_t *tx)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
return (zap_remove(os, obj, name, tx));
}
int
zap_lookup_int(objset_t *os, uint64_t obj, uint64_t value)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)value);
return (zap_lookup(os, obj, name, 8, 1, &value));
}
int
zap_add_int_key(objset_t *os, uint64_t obj,
uint64_t key, uint64_t value, dmu_tx_t *tx)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
return (zap_add(os, obj, name, 8, 1, &value, tx));
}
int
zap_update_int_key(objset_t *os, uint64_t obj,
uint64_t key, uint64_t value, dmu_tx_t *tx)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
return (zap_update(os, obj, name, 8, 1, &value, tx));
}
int
zap_lookup_int_key(objset_t *os, uint64_t obj, uint64_t key, uint64_t *valuep)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
return (zap_lookup(os, obj, name, 8, 1, valuep));
}
int
zap_increment(objset_t *os, uint64_t obj, const char *name, int64_t delta,
dmu_tx_t *tx)
{
uint64_t value = 0;
if (delta == 0)
return (0);
int err = zap_lookup(os, obj, name, 8, 1, &value);
if (err != 0 && err != ENOENT)
return (err);
value += delta;
if (value == 0)
err = zap_remove(os, obj, name, tx);
else
err = zap_update(os, obj, name, 8, 1, &value, tx);
return (err);
}
int
zap_increment_int(objset_t *os, uint64_t obj, uint64_t key, int64_t delta,
dmu_tx_t *tx)
{
char name[20];
(void) snprintf(name, sizeof (name), "%llx", (longlong_t)key);
return (zap_increment(os, obj, name, delta, tx));
}
/*
* 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 we are reading from the beginning, we're almost certain to
* iterate over the entire ZAP object. If there are multiple leaf
* blocks (freeblk > 2), prefetch the whole object (up to
* dmu_prefetch_max bytes), so that we read the leaf blocks
* concurrently. (Unless noprefetch was requested via
* zap_cursor_init_noprefetch()).
*/
if (zc->zc_hash == 0 && zap_iterate_prefetch &&
zc->zc_prefetch && zap_f_phys(zap)->zap_freeblk > 2) {
dmu_prefetch(zc->zc_objset, zc->zc_zapobj, 0, 0,
zap_f_phys(zap)->zap_freeblk << FZAP_BLOCK_SHIFT(zap),
ZIO_PRIORITY_ASYNC_READ);
}
if (zc->zc_leaf &&
(ZAP_HASH_IDX(zc->zc_hash,
zap_leaf_phys(zc->zc_leaf)->l_hdr.lh_prefix_len) !=
zap_leaf_phys(zc->zc_leaf)->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) {
if (zap_leaf_phys(l)->l_hdr.lh_prefix_len == 0) {
zc->zc_hash = -1ULL;
zc->zc_cd = 0;
} else {
uint64_t nocare = (1ULL <<
(64 - zap_leaf_phys(l)->l_hdr.lh_prefix_len)) - 1;
zc->zc_hash = (zc->zc_hash & ~nocare) + nocare + 1;
zc->zc_cd = 0;
if (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(zap, &zeh,
sizeof (za->za_name), za->za_name);
ASSERT(err == 0);
za->za_normalization_conflict =
zap_entry_normalization_conflict(&zeh,
NULL, za->za_name, zap);
}
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)
{
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 (int i = 0; i < len; i++) {
zap_leaf_t *l;
if (tbl[i] == lastblk)
continue;
lastblk = tbl[i];
int 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_f_phys(zap)->zap_num_leafs;
zs->zs_num_entries = zap_f_phys(zap)->zap_num_entries;
zs->zs_num_blocks = zap_f_phys(zap)->zap_freeblk;
zs->zs_block_type = zap_f_phys(zap)->zap_block_type;
zs->zs_magic = zap_f_phys(zap)->zap_magic;
zs->zs_salt = zap_f_phys(zap)->zap_salt;
/*
* Set zap_ptrtbl fields
*/
zs->zs_ptrtbl_len = 1ULL << zap_f_phys(zap)->zap_ptrtbl.zt_shift;
zs->zs_ptrtbl_nextblk = zap_f_phys(zap)->zap_ptrtbl.zt_nextblk;
zs->zs_ptrtbl_blks_copied =
zap_f_phys(zap)->zap_ptrtbl.zt_blks_copied;
zs->zs_ptrtbl_zt_blk = zap_f_phys(zap)->zap_ptrtbl.zt_blk;
zs->zs_ptrtbl_zt_numblks = zap_f_phys(zap)->zap_ptrtbl.zt_numblks;
zs->zs_ptrtbl_zt_shift = zap_f_phys(zap)->zap_ptrtbl.zt_shift;
if (zap_f_phys(zap)->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 {
dmu_prefetch(zap->zap_objset, zap->zap_object, 0,
zap_f_phys(zap)->zap_ptrtbl.zt_blk << bs,
zap_f_phys(zap)->zap_ptrtbl.zt_numblks << bs,
ZIO_PRIORITY_SYNC_READ);
for (int b = 0; b < zap_f_phys(zap)->zap_ptrtbl.zt_numblks;
b++) {
dmu_buf_t *db;
int err;
err = dmu_buf_hold(zap->zap_objset, zap->zap_object,
(zap_f_phys(zap)->zap_ptrtbl.zt_blk + b) << bs,
FTAG, &db, DMU_READ_NO_PREFETCH);
if (err == 0) {
zap_stats_ptrtbl(zap, db->db_data,
1<<(bs-3), zs);
dmu_buf_rele(db, FTAG);
}
}
}
}
/* CSTYLED */
ZFS_MODULE_PARAM(zfs, , zap_iterate_prefetch, INT, ZMOD_RW,
"When iterating ZAP object, prefetch it");
|