freebsd-nq/module/zfs/ddt.c
Matthew Macy 03fdcb9adc Make module tunables cross platform
Adds ZFS_MODULE_PARAM to abstract module parameter
setting to operating systems other than Linux.

Reviewed-by: Jorgen Lundman <lundman@lundman.net>
Reviewed-by: Igor Kozhukhov <igor@dilos.org>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Matt Macy <mmacy@FreeBSD.org>
Signed-off-by: Ryan Moeller <ryan@ixsystems.com>
Closes #9230
2019-09-05 14:49:49 -07:00

1194 lines
28 KiB
C

/*
* 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 (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2012, 2016 by Delphix. All rights reserved.
*/
#include <sys/zfs_context.h>
#include <sys/spa.h>
#include <sys/spa_impl.h>
#include <sys/zio.h>
#include <sys/ddt.h>
#include <sys/zap.h>
#include <sys/dmu_tx.h>
#include <sys/arc.h>
#include <sys/dsl_pool.h>
#include <sys/zio_checksum.h>
#include <sys/zio_compress.h>
#include <sys/dsl_scan.h>
#include <sys/abd.h>
static kmem_cache_t *ddt_cache;
static kmem_cache_t *ddt_entry_cache;
/*
* Enable/disable prefetching of dedup-ed blocks which are going to be freed.
*/
int zfs_dedup_prefetch = 0;
static const ddt_ops_t *ddt_ops[DDT_TYPES] = {
&ddt_zap_ops,
};
static const char *ddt_class_name[DDT_CLASSES] = {
"ditto",
"duplicate",
"unique",
};
static void
ddt_object_create(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
dmu_tx_t *tx)
{
spa_t *spa = ddt->ddt_spa;
objset_t *os = ddt->ddt_os;
uint64_t *objectp = &ddt->ddt_object[type][class];
boolean_t prehash = zio_checksum_table[ddt->ddt_checksum].ci_flags &
ZCHECKSUM_FLAG_DEDUP;
char name[DDT_NAMELEN];
ddt_object_name(ddt, type, class, name);
ASSERT(*objectp == 0);
VERIFY(ddt_ops[type]->ddt_op_create(os, objectp, tx, prehash) == 0);
ASSERT(*objectp != 0);
VERIFY(zap_add(os, DMU_POOL_DIRECTORY_OBJECT, name,
sizeof (uint64_t), 1, objectp, tx) == 0);
VERIFY(zap_add(os, spa->spa_ddt_stat_object, name,
sizeof (uint64_t), sizeof (ddt_histogram_t) / sizeof (uint64_t),
&ddt->ddt_histogram[type][class], tx) == 0);
}
static void
ddt_object_destroy(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
dmu_tx_t *tx)
{
spa_t *spa = ddt->ddt_spa;
objset_t *os = ddt->ddt_os;
uint64_t *objectp = &ddt->ddt_object[type][class];
uint64_t count;
char name[DDT_NAMELEN];
ddt_object_name(ddt, type, class, name);
ASSERT(*objectp != 0);
ASSERT(ddt_histogram_empty(&ddt->ddt_histogram[type][class]));
VERIFY(ddt_object_count(ddt, type, class, &count) == 0 && count == 0);
VERIFY(zap_remove(os, DMU_POOL_DIRECTORY_OBJECT, name, tx) == 0);
VERIFY(zap_remove(os, spa->spa_ddt_stat_object, name, tx) == 0);
VERIFY(ddt_ops[type]->ddt_op_destroy(os, *objectp, tx) == 0);
bzero(&ddt->ddt_object_stats[type][class], sizeof (ddt_object_t));
*objectp = 0;
}
static int
ddt_object_load(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
{
ddt_object_t *ddo = &ddt->ddt_object_stats[type][class];
dmu_object_info_t doi;
uint64_t count;
char name[DDT_NAMELEN];
int error;
ddt_object_name(ddt, type, class, name);
error = zap_lookup(ddt->ddt_os, DMU_POOL_DIRECTORY_OBJECT, name,
sizeof (uint64_t), 1, &ddt->ddt_object[type][class]);
if (error != 0)
return (error);
error = zap_lookup(ddt->ddt_os, ddt->ddt_spa->spa_ddt_stat_object, name,
sizeof (uint64_t), sizeof (ddt_histogram_t) / sizeof (uint64_t),
&ddt->ddt_histogram[type][class]);
if (error != 0)
return (error);
/*
* Seed the cached statistics.
*/
error = ddt_object_info(ddt, type, class, &doi);
if (error)
return (error);
error = ddt_object_count(ddt, type, class, &count);
if (error)
return (error);
ddo->ddo_count = count;
ddo->ddo_dspace = doi.doi_physical_blocks_512 << 9;
ddo->ddo_mspace = doi.doi_fill_count * doi.doi_data_block_size;
return (0);
}
static void
ddt_object_sync(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
dmu_tx_t *tx)
{
ddt_object_t *ddo = &ddt->ddt_object_stats[type][class];
dmu_object_info_t doi;
uint64_t count;
char name[DDT_NAMELEN];
ddt_object_name(ddt, type, class, name);
VERIFY(zap_update(ddt->ddt_os, ddt->ddt_spa->spa_ddt_stat_object, name,
sizeof (uint64_t), sizeof (ddt_histogram_t) / sizeof (uint64_t),
&ddt->ddt_histogram[type][class], tx) == 0);
/*
* Cache DDT statistics; this is the only time they'll change.
*/
VERIFY(ddt_object_info(ddt, type, class, &doi) == 0);
VERIFY(ddt_object_count(ddt, type, class, &count) == 0);
ddo->ddo_count = count;
ddo->ddo_dspace = doi.doi_physical_blocks_512 << 9;
ddo->ddo_mspace = doi.doi_fill_count * doi.doi_data_block_size;
}
static int
ddt_object_lookup(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
ddt_entry_t *dde)
{
if (!ddt_object_exists(ddt, type, class))
return (SET_ERROR(ENOENT));
return (ddt_ops[type]->ddt_op_lookup(ddt->ddt_os,
ddt->ddt_object[type][class], dde));
}
static void
ddt_object_prefetch(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
ddt_entry_t *dde)
{
if (!ddt_object_exists(ddt, type, class))
return;
ddt_ops[type]->ddt_op_prefetch(ddt->ddt_os,
ddt->ddt_object[type][class], dde);
}
int
ddt_object_update(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
ddt_entry_t *dde, dmu_tx_t *tx)
{
ASSERT(ddt_object_exists(ddt, type, class));
return (ddt_ops[type]->ddt_op_update(ddt->ddt_os,
ddt->ddt_object[type][class], dde, tx));
}
static int
ddt_object_remove(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
ddt_entry_t *dde, dmu_tx_t *tx)
{
ASSERT(ddt_object_exists(ddt, type, class));
return (ddt_ops[type]->ddt_op_remove(ddt->ddt_os,
ddt->ddt_object[type][class], dde, tx));
}
int
ddt_object_walk(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
uint64_t *walk, ddt_entry_t *dde)
{
ASSERT(ddt_object_exists(ddt, type, class));
return (ddt_ops[type]->ddt_op_walk(ddt->ddt_os,
ddt->ddt_object[type][class], dde, walk));
}
int
ddt_object_count(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
uint64_t *count)
{
ASSERT(ddt_object_exists(ddt, type, class));
return (ddt_ops[type]->ddt_op_count(ddt->ddt_os,
ddt->ddt_object[type][class], count));
}
int
ddt_object_info(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
dmu_object_info_t *doi)
{
if (!ddt_object_exists(ddt, type, class))
return (SET_ERROR(ENOENT));
return (dmu_object_info(ddt->ddt_os, ddt->ddt_object[type][class],
doi));
}
boolean_t
ddt_object_exists(ddt_t *ddt, enum ddt_type type, enum ddt_class class)
{
return (!!ddt->ddt_object[type][class]);
}
void
ddt_object_name(ddt_t *ddt, enum ddt_type type, enum ddt_class class,
char *name)
{
(void) sprintf(name, DMU_POOL_DDT,
zio_checksum_table[ddt->ddt_checksum].ci_name,
ddt_ops[type]->ddt_op_name, ddt_class_name[class]);
}
void
ddt_bp_fill(const ddt_phys_t *ddp, blkptr_t *bp, uint64_t txg)
{
ASSERT(txg != 0);
for (int d = 0; d < SPA_DVAS_PER_BP; d++)
bp->blk_dva[d] = ddp->ddp_dva[d];
BP_SET_BIRTH(bp, txg, ddp->ddp_phys_birth);
}
/*
* The bp created via this function may be used for repairs and scrub, but it
* will be missing the salt / IV required to do a full decrypting read.
*/
void
ddt_bp_create(enum zio_checksum checksum,
const ddt_key_t *ddk, const ddt_phys_t *ddp, blkptr_t *bp)
{
BP_ZERO(bp);
if (ddp != NULL)
ddt_bp_fill(ddp, bp, ddp->ddp_phys_birth);
bp->blk_cksum = ddk->ddk_cksum;
BP_SET_LSIZE(bp, DDK_GET_LSIZE(ddk));
BP_SET_PSIZE(bp, DDK_GET_PSIZE(ddk));
BP_SET_COMPRESS(bp, DDK_GET_COMPRESS(ddk));
BP_SET_CRYPT(bp, DDK_GET_CRYPT(ddk));
BP_SET_FILL(bp, 1);
BP_SET_CHECKSUM(bp, checksum);
BP_SET_TYPE(bp, DMU_OT_DEDUP);
BP_SET_LEVEL(bp, 0);
BP_SET_DEDUP(bp, 1);
BP_SET_BYTEORDER(bp, ZFS_HOST_BYTEORDER);
}
void
ddt_key_fill(ddt_key_t *ddk, const blkptr_t *bp)
{
ddk->ddk_cksum = bp->blk_cksum;
ddk->ddk_prop = 0;
ASSERT(BP_IS_ENCRYPTED(bp) || !BP_USES_CRYPT(bp));
DDK_SET_LSIZE(ddk, BP_GET_LSIZE(bp));
DDK_SET_PSIZE(ddk, BP_GET_PSIZE(bp));
DDK_SET_COMPRESS(ddk, BP_GET_COMPRESS(bp));
DDK_SET_CRYPT(ddk, BP_USES_CRYPT(bp));
}
void
ddt_phys_fill(ddt_phys_t *ddp, const blkptr_t *bp)
{
ASSERT(ddp->ddp_phys_birth == 0);
for (int d = 0; d < SPA_DVAS_PER_BP; d++)
ddp->ddp_dva[d] = bp->blk_dva[d];
ddp->ddp_phys_birth = BP_PHYSICAL_BIRTH(bp);
}
void
ddt_phys_clear(ddt_phys_t *ddp)
{
bzero(ddp, sizeof (*ddp));
}
void
ddt_phys_addref(ddt_phys_t *ddp)
{
ddp->ddp_refcnt++;
}
void
ddt_phys_decref(ddt_phys_t *ddp)
{
if (ddp) {
ASSERT(ddp->ddp_refcnt > 0);
ddp->ddp_refcnt--;
}
}
void
ddt_phys_free(ddt_t *ddt, ddt_key_t *ddk, ddt_phys_t *ddp, uint64_t txg)
{
blkptr_t blk;
ddt_bp_create(ddt->ddt_checksum, ddk, ddp, &blk);
/*
* We clear the dedup bit so that zio_free() will actually free the
* space, rather than just decrementing the refcount in the DDT.
*/
BP_SET_DEDUP(&blk, 0);
ddt_phys_clear(ddp);
zio_free(ddt->ddt_spa, txg, &blk);
}
ddt_phys_t *
ddt_phys_select(const ddt_entry_t *dde, const blkptr_t *bp)
{
ddt_phys_t *ddp = (ddt_phys_t *)dde->dde_phys;
for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
if (DVA_EQUAL(BP_IDENTITY(bp), &ddp->ddp_dva[0]) &&
BP_PHYSICAL_BIRTH(bp) == ddp->ddp_phys_birth)
return (ddp);
}
return (NULL);
}
uint64_t
ddt_phys_total_refcnt(const ddt_entry_t *dde)
{
uint64_t refcnt = 0;
for (int p = DDT_PHYS_SINGLE; p <= DDT_PHYS_TRIPLE; p++)
refcnt += dde->dde_phys[p].ddp_refcnt;
return (refcnt);
}
static void
ddt_stat_generate(ddt_t *ddt, ddt_entry_t *dde, ddt_stat_t *dds)
{
spa_t *spa = ddt->ddt_spa;
ddt_phys_t *ddp = dde->dde_phys;
ddt_key_t *ddk = &dde->dde_key;
uint64_t lsize = DDK_GET_LSIZE(ddk);
uint64_t psize = DDK_GET_PSIZE(ddk);
bzero(dds, sizeof (*dds));
for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
uint64_t dsize = 0;
uint64_t refcnt = ddp->ddp_refcnt;
if (ddp->ddp_phys_birth == 0)
continue;
for (int d = 0; d < DDE_GET_NDVAS(dde); d++)
dsize += dva_get_dsize_sync(spa, &ddp->ddp_dva[d]);
dds->dds_blocks += 1;
dds->dds_lsize += lsize;
dds->dds_psize += psize;
dds->dds_dsize += dsize;
dds->dds_ref_blocks += refcnt;
dds->dds_ref_lsize += lsize * refcnt;
dds->dds_ref_psize += psize * refcnt;
dds->dds_ref_dsize += dsize * refcnt;
}
}
void
ddt_stat_add(ddt_stat_t *dst, const ddt_stat_t *src, uint64_t neg)
{
const uint64_t *s = (const uint64_t *)src;
uint64_t *d = (uint64_t *)dst;
uint64_t *d_end = (uint64_t *)(dst + 1);
ASSERT(neg == 0 || neg == -1ULL); /* add or subtract */
while (d < d_end)
*d++ += (*s++ ^ neg) - neg;
}
static void
ddt_stat_update(ddt_t *ddt, ddt_entry_t *dde, uint64_t neg)
{
ddt_stat_t dds;
ddt_histogram_t *ddh;
int bucket;
ddt_stat_generate(ddt, dde, &dds);
bucket = highbit64(dds.dds_ref_blocks) - 1;
ASSERT(bucket >= 0);
ddh = &ddt->ddt_histogram[dde->dde_type][dde->dde_class];
ddt_stat_add(&ddh->ddh_stat[bucket], &dds, neg);
}
void
ddt_histogram_add(ddt_histogram_t *dst, const ddt_histogram_t *src)
{
for (int h = 0; h < 64; h++)
ddt_stat_add(&dst->ddh_stat[h], &src->ddh_stat[h], 0);
}
void
ddt_histogram_stat(ddt_stat_t *dds, const ddt_histogram_t *ddh)
{
bzero(dds, sizeof (*dds));
for (int h = 0; h < 64; h++)
ddt_stat_add(dds, &ddh->ddh_stat[h], 0);
}
boolean_t
ddt_histogram_empty(const ddt_histogram_t *ddh)
{
const uint64_t *s = (const uint64_t *)ddh;
const uint64_t *s_end = (const uint64_t *)(ddh + 1);
while (s < s_end)
if (*s++ != 0)
return (B_FALSE);
return (B_TRUE);
}
void
ddt_get_dedup_object_stats(spa_t *spa, ddt_object_t *ddo_total)
{
/* Sum the statistics we cached in ddt_object_sync(). */
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
for (enum ddt_class class = 0; class < DDT_CLASSES;
class++) {
ddt_object_t *ddo =
&ddt->ddt_object_stats[type][class];
ddo_total->ddo_count += ddo->ddo_count;
ddo_total->ddo_dspace += ddo->ddo_dspace;
ddo_total->ddo_mspace += ddo->ddo_mspace;
}
}
}
/* ... and compute the averages. */
if (ddo_total->ddo_count != 0) {
ddo_total->ddo_dspace /= ddo_total->ddo_count;
ddo_total->ddo_mspace /= ddo_total->ddo_count;
}
}
void
ddt_get_dedup_histogram(spa_t *spa, ddt_histogram_t *ddh)
{
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
for (enum ddt_class class = 0; class < DDT_CLASSES;
class++) {
ddt_histogram_add(ddh,
&ddt->ddt_histogram_cache[type][class]);
}
}
}
}
void
ddt_get_dedup_stats(spa_t *spa, ddt_stat_t *dds_total)
{
ddt_histogram_t *ddh_total;
ddh_total = kmem_zalloc(sizeof (ddt_histogram_t), KM_SLEEP);
ddt_get_dedup_histogram(spa, ddh_total);
ddt_histogram_stat(dds_total, ddh_total);
kmem_free(ddh_total, sizeof (ddt_histogram_t));
}
uint64_t
ddt_get_dedup_dspace(spa_t *spa)
{
ddt_stat_t dds_total;
if (spa->spa_dedup_dspace != ~0ULL)
return (spa->spa_dedup_dspace);
bzero(&dds_total, sizeof (ddt_stat_t));
/* Calculate and cache the stats */
ddt_get_dedup_stats(spa, &dds_total);
spa->spa_dedup_dspace = dds_total.dds_ref_dsize - dds_total.dds_dsize;
return (spa->spa_dedup_dspace);
}
uint64_t
ddt_get_pool_dedup_ratio(spa_t *spa)
{
ddt_stat_t dds_total = { 0 };
ddt_get_dedup_stats(spa, &dds_total);
if (dds_total.dds_dsize == 0)
return (100);
return (dds_total.dds_ref_dsize * 100 / dds_total.dds_dsize);
}
size_t
ddt_compress(void *src, uchar_t *dst, size_t s_len, size_t d_len)
{
uchar_t *version = dst++;
int cpfunc = ZIO_COMPRESS_ZLE;
zio_compress_info_t *ci = &zio_compress_table[cpfunc];
size_t c_len;
ASSERT(d_len >= s_len + 1); /* no compression plus version byte */
c_len = ci->ci_compress(src, dst, s_len, d_len - 1, ci->ci_level);
if (c_len == s_len) {
cpfunc = ZIO_COMPRESS_OFF;
bcopy(src, dst, s_len);
}
*version = cpfunc;
/* CONSTCOND */
if (ZFS_HOST_BYTEORDER)
*version |= DDT_COMPRESS_BYTEORDER_MASK;
return (c_len + 1);
}
void
ddt_decompress(uchar_t *src, void *dst, size_t s_len, size_t d_len)
{
uchar_t version = *src++;
int cpfunc = version & DDT_COMPRESS_FUNCTION_MASK;
zio_compress_info_t *ci = &zio_compress_table[cpfunc];
if (ci->ci_decompress != NULL)
(void) ci->ci_decompress(src, dst, s_len, d_len, ci->ci_level);
else
bcopy(src, dst, d_len);
if (((version & DDT_COMPRESS_BYTEORDER_MASK) != 0) !=
(ZFS_HOST_BYTEORDER != 0))
byteswap_uint64_array(dst, d_len);
}
ddt_t *
ddt_select_by_checksum(spa_t *spa, enum zio_checksum c)
{
return (spa->spa_ddt[c]);
}
ddt_t *
ddt_select(spa_t *spa, const blkptr_t *bp)
{
return (spa->spa_ddt[BP_GET_CHECKSUM(bp)]);
}
void
ddt_enter(ddt_t *ddt)
{
mutex_enter(&ddt->ddt_lock);
}
void
ddt_exit(ddt_t *ddt)
{
mutex_exit(&ddt->ddt_lock);
}
void
ddt_init(void)
{
ddt_cache = kmem_cache_create("ddt_cache",
sizeof (ddt_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
ddt_entry_cache = kmem_cache_create("ddt_entry_cache",
sizeof (ddt_entry_t), 0, NULL, NULL, NULL, NULL, NULL, 0);
}
void
ddt_fini(void)
{
kmem_cache_destroy(ddt_entry_cache);
kmem_cache_destroy(ddt_cache);
}
static ddt_entry_t *
ddt_alloc(const ddt_key_t *ddk)
{
ddt_entry_t *dde;
dde = kmem_cache_alloc(ddt_entry_cache, KM_SLEEP);
bzero(dde, sizeof (ddt_entry_t));
cv_init(&dde->dde_cv, NULL, CV_DEFAULT, NULL);
dde->dde_key = *ddk;
return (dde);
}
static void
ddt_free(ddt_entry_t *dde)
{
ASSERT(!dde->dde_loading);
for (int p = 0; p < DDT_PHYS_TYPES; p++)
ASSERT(dde->dde_lead_zio[p] == NULL);
if (dde->dde_repair_abd != NULL)
abd_free(dde->dde_repair_abd);
cv_destroy(&dde->dde_cv);
kmem_cache_free(ddt_entry_cache, dde);
}
void
ddt_remove(ddt_t *ddt, ddt_entry_t *dde)
{
ASSERT(MUTEX_HELD(&ddt->ddt_lock));
avl_remove(&ddt->ddt_tree, dde);
ddt_free(dde);
}
ddt_entry_t *
ddt_lookup(ddt_t *ddt, const blkptr_t *bp, boolean_t add)
{
ddt_entry_t *dde, dde_search;
enum ddt_type type;
enum ddt_class class;
avl_index_t where;
int error;
ASSERT(MUTEX_HELD(&ddt->ddt_lock));
ddt_key_fill(&dde_search.dde_key, bp);
dde = avl_find(&ddt->ddt_tree, &dde_search, &where);
if (dde == NULL) {
if (!add)
return (NULL);
dde = ddt_alloc(&dde_search.dde_key);
avl_insert(&ddt->ddt_tree, dde, where);
}
while (dde->dde_loading)
cv_wait(&dde->dde_cv, &ddt->ddt_lock);
if (dde->dde_loaded)
return (dde);
dde->dde_loading = B_TRUE;
ddt_exit(ddt);
error = ENOENT;
for (type = 0; type < DDT_TYPES; type++) {
for (class = 0; class < DDT_CLASSES; class++) {
error = ddt_object_lookup(ddt, type, class, dde);
if (error != ENOENT) {
ASSERT0(error);
break;
}
}
if (error != ENOENT)
break;
}
ddt_enter(ddt);
ASSERT(dde->dde_loaded == B_FALSE);
ASSERT(dde->dde_loading == B_TRUE);
dde->dde_type = type; /* will be DDT_TYPES if no entry found */
dde->dde_class = class; /* will be DDT_CLASSES if no entry found */
dde->dde_loaded = B_TRUE;
dde->dde_loading = B_FALSE;
if (error == 0)
ddt_stat_update(ddt, dde, -1ULL);
cv_broadcast(&dde->dde_cv);
return (dde);
}
void
ddt_prefetch(spa_t *spa, const blkptr_t *bp)
{
ddt_t *ddt;
ddt_entry_t dde;
if (!zfs_dedup_prefetch || bp == NULL || !BP_GET_DEDUP(bp))
return;
/*
* We only remove the DDT once all tables are empty and only
* prefetch dedup blocks when there are entries in the DDT.
* Thus no locking is required as the DDT can't disappear on us.
*/
ddt = ddt_select(spa, bp);
ddt_key_fill(&dde.dde_key, bp);
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
for (enum ddt_class class = 0; class < DDT_CLASSES; class++) {
ddt_object_prefetch(ddt, type, class, &dde);
}
}
}
/*
* Opaque struct used for ddt_key comparison
*/
#define DDT_KEY_CMP_LEN (sizeof (ddt_key_t) / sizeof (uint16_t))
typedef struct ddt_key_cmp {
uint16_t u16[DDT_KEY_CMP_LEN];
} ddt_key_cmp_t;
int
ddt_entry_compare(const void *x1, const void *x2)
{
const ddt_entry_t *dde1 = x1;
const ddt_entry_t *dde2 = x2;
const ddt_key_cmp_t *k1 = (const ddt_key_cmp_t *)&dde1->dde_key;
const ddt_key_cmp_t *k2 = (const ddt_key_cmp_t *)&dde2->dde_key;
int32_t cmp = 0;
for (int i = 0; i < DDT_KEY_CMP_LEN; i++) {
cmp = (int32_t)k1->u16[i] - (int32_t)k2->u16[i];
if (likely(cmp))
break;
}
return (AVL_ISIGN(cmp));
}
static ddt_t *
ddt_table_alloc(spa_t *spa, enum zio_checksum c)
{
ddt_t *ddt;
ddt = kmem_cache_alloc(ddt_cache, KM_SLEEP);
bzero(ddt, sizeof (ddt_t));
mutex_init(&ddt->ddt_lock, NULL, MUTEX_DEFAULT, NULL);
avl_create(&ddt->ddt_tree, ddt_entry_compare,
sizeof (ddt_entry_t), offsetof(ddt_entry_t, dde_node));
avl_create(&ddt->ddt_repair_tree, ddt_entry_compare,
sizeof (ddt_entry_t), offsetof(ddt_entry_t, dde_node));
ddt->ddt_checksum = c;
ddt->ddt_spa = spa;
ddt->ddt_os = spa->spa_meta_objset;
return (ddt);
}
static void
ddt_table_free(ddt_t *ddt)
{
ASSERT(avl_numnodes(&ddt->ddt_tree) == 0);
ASSERT(avl_numnodes(&ddt->ddt_repair_tree) == 0);
avl_destroy(&ddt->ddt_tree);
avl_destroy(&ddt->ddt_repair_tree);
mutex_destroy(&ddt->ddt_lock);
kmem_cache_free(ddt_cache, ddt);
}
void
ddt_create(spa_t *spa)
{
spa->spa_dedup_checksum = ZIO_DEDUPCHECKSUM;
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++)
spa->spa_ddt[c] = ddt_table_alloc(spa, c);
}
int
ddt_load(spa_t *spa)
{
int error;
ddt_create(spa);
error = zap_lookup(spa->spa_meta_objset, DMU_POOL_DIRECTORY_OBJECT,
DMU_POOL_DDT_STATS, sizeof (uint64_t), 1,
&spa->spa_ddt_stat_object);
if (error)
return (error == ENOENT ? 0 : error);
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
for (enum ddt_class class = 0; class < DDT_CLASSES;
class++) {
error = ddt_object_load(ddt, type, class);
if (error != 0 && error != ENOENT)
return (error);
}
}
/*
* Seed the cached histograms.
*/
bcopy(ddt->ddt_histogram, &ddt->ddt_histogram_cache,
sizeof (ddt->ddt_histogram));
spa->spa_dedup_dspace = ~0ULL;
}
return (0);
}
void
ddt_unload(spa_t *spa)
{
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
if (spa->spa_ddt[c]) {
ddt_table_free(spa->spa_ddt[c]);
spa->spa_ddt[c] = NULL;
}
}
}
boolean_t
ddt_class_contains(spa_t *spa, enum ddt_class max_class, const blkptr_t *bp)
{
ddt_t *ddt;
ddt_entry_t *dde;
if (!BP_GET_DEDUP(bp))
return (B_FALSE);
if (max_class == DDT_CLASS_UNIQUE)
return (B_TRUE);
ddt = spa->spa_ddt[BP_GET_CHECKSUM(bp)];
dde = kmem_cache_alloc(ddt_entry_cache, KM_SLEEP);
ddt_key_fill(&(dde->dde_key), bp);
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
for (enum ddt_class class = 0; class <= max_class; class++) {
if (ddt_object_lookup(ddt, type, class, dde) == 0) {
kmem_cache_free(ddt_entry_cache, dde);
return (B_TRUE);
}
}
}
kmem_cache_free(ddt_entry_cache, dde);
return (B_FALSE);
}
ddt_entry_t *
ddt_repair_start(ddt_t *ddt, const blkptr_t *bp)
{
ddt_key_t ddk;
ddt_entry_t *dde;
ddt_key_fill(&ddk, bp);
dde = ddt_alloc(&ddk);
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
for (enum ddt_class class = 0; class < DDT_CLASSES; class++) {
/*
* We can only do repair if there are multiple copies
* of the block. For anything in the UNIQUE class,
* there's definitely only one copy, so don't even try.
*/
if (class != DDT_CLASS_UNIQUE &&
ddt_object_lookup(ddt, type, class, dde) == 0)
return (dde);
}
}
bzero(dde->dde_phys, sizeof (dde->dde_phys));
return (dde);
}
void
ddt_repair_done(ddt_t *ddt, ddt_entry_t *dde)
{
avl_index_t where;
ddt_enter(ddt);
if (dde->dde_repair_abd != NULL && spa_writeable(ddt->ddt_spa) &&
avl_find(&ddt->ddt_repair_tree, dde, &where) == NULL)
avl_insert(&ddt->ddt_repair_tree, dde, where);
else
ddt_free(dde);
ddt_exit(ddt);
}
static void
ddt_repair_entry_done(zio_t *zio)
{
ddt_entry_t *rdde = zio->io_private;
ddt_free(rdde);
}
static void
ddt_repair_entry(ddt_t *ddt, ddt_entry_t *dde, ddt_entry_t *rdde, zio_t *rio)
{
ddt_phys_t *ddp = dde->dde_phys;
ddt_phys_t *rddp = rdde->dde_phys;
ddt_key_t *ddk = &dde->dde_key;
ddt_key_t *rddk = &rdde->dde_key;
zio_t *zio;
blkptr_t blk;
zio = zio_null(rio, rio->io_spa, NULL,
ddt_repair_entry_done, rdde, rio->io_flags);
for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++, rddp++) {
if (ddp->ddp_phys_birth == 0 ||
ddp->ddp_phys_birth != rddp->ddp_phys_birth ||
bcmp(ddp->ddp_dva, rddp->ddp_dva, sizeof (ddp->ddp_dva)))
continue;
ddt_bp_create(ddt->ddt_checksum, ddk, ddp, &blk);
zio_nowait(zio_rewrite(zio, zio->io_spa, 0, &blk,
rdde->dde_repair_abd, DDK_GET_PSIZE(rddk), NULL, NULL,
ZIO_PRIORITY_SYNC_WRITE, ZIO_DDT_CHILD_FLAGS(zio), NULL));
}
zio_nowait(zio);
}
static void
ddt_repair_table(ddt_t *ddt, zio_t *rio)
{
spa_t *spa = ddt->ddt_spa;
ddt_entry_t *dde, *rdde_next, *rdde;
avl_tree_t *t = &ddt->ddt_repair_tree;
blkptr_t blk;
if (spa_sync_pass(spa) > 1)
return;
ddt_enter(ddt);
for (rdde = avl_first(t); rdde != NULL; rdde = rdde_next) {
rdde_next = AVL_NEXT(t, rdde);
avl_remove(&ddt->ddt_repair_tree, rdde);
ddt_exit(ddt);
ddt_bp_create(ddt->ddt_checksum, &rdde->dde_key, NULL, &blk);
dde = ddt_repair_start(ddt, &blk);
ddt_repair_entry(ddt, dde, rdde, rio);
ddt_repair_done(ddt, dde);
ddt_enter(ddt);
}
ddt_exit(ddt);
}
static void
ddt_sync_entry(ddt_t *ddt, ddt_entry_t *dde, dmu_tx_t *tx, uint64_t txg)
{
dsl_pool_t *dp = ddt->ddt_spa->spa_dsl_pool;
ddt_phys_t *ddp = dde->dde_phys;
ddt_key_t *ddk = &dde->dde_key;
enum ddt_type otype = dde->dde_type;
enum ddt_type ntype = DDT_TYPE_CURRENT;
enum ddt_class oclass = dde->dde_class;
enum ddt_class nclass;
uint64_t total_refcnt = 0;
ASSERT(dde->dde_loaded);
ASSERT(!dde->dde_loading);
for (int p = 0; p < DDT_PHYS_TYPES; p++, ddp++) {
ASSERT(dde->dde_lead_zio[p] == NULL);
if (ddp->ddp_phys_birth == 0) {
ASSERT(ddp->ddp_refcnt == 0);
continue;
}
if (p == DDT_PHYS_DITTO) {
/*
* Note, we no longer create DDT-DITTO blocks, but we
* don't want to leak any written by older software.
*/
ddt_phys_free(ddt, ddk, ddp, txg);
continue;
}
if (ddp->ddp_refcnt == 0)
ddt_phys_free(ddt, ddk, ddp, txg);
total_refcnt += ddp->ddp_refcnt;
}
/* We do not create new DDT-DITTO blocks. */
ASSERT0(dde->dde_phys[DDT_PHYS_DITTO].ddp_phys_birth);
if (total_refcnt > 1)
nclass = DDT_CLASS_DUPLICATE;
else
nclass = DDT_CLASS_UNIQUE;
if (otype != DDT_TYPES &&
(otype != ntype || oclass != nclass || total_refcnt == 0)) {
VERIFY(ddt_object_remove(ddt, otype, oclass, dde, tx) == 0);
ASSERT(ddt_object_lookup(ddt, otype, oclass, dde) == ENOENT);
}
if (total_refcnt != 0) {
dde->dde_type = ntype;
dde->dde_class = nclass;
ddt_stat_update(ddt, dde, 0);
if (!ddt_object_exists(ddt, ntype, nclass))
ddt_object_create(ddt, ntype, nclass, tx);
VERIFY(ddt_object_update(ddt, ntype, nclass, dde, tx) == 0);
/*
* If the class changes, the order that we scan this bp
* changes. If it decreases, we could miss it, so
* scan it right now. (This covers both class changing
* while we are doing ddt_walk(), and when we are
* traversing.)
*/
if (nclass < oclass) {
dsl_scan_ddt_entry(dp->dp_scan,
ddt->ddt_checksum, dde, tx);
}
}
}
static void
ddt_sync_table(ddt_t *ddt, dmu_tx_t *tx, uint64_t txg)
{
spa_t *spa = ddt->ddt_spa;
ddt_entry_t *dde;
void *cookie = NULL;
if (avl_numnodes(&ddt->ddt_tree) == 0)
return;
ASSERT(spa->spa_uberblock.ub_version >= SPA_VERSION_DEDUP);
if (spa->spa_ddt_stat_object == 0) {
spa->spa_ddt_stat_object = zap_create_link(ddt->ddt_os,
DMU_OT_DDT_STATS, DMU_POOL_DIRECTORY_OBJECT,
DMU_POOL_DDT_STATS, tx);
}
while ((dde = avl_destroy_nodes(&ddt->ddt_tree, &cookie)) != NULL) {
ddt_sync_entry(ddt, dde, tx, txg);
ddt_free(dde);
}
for (enum ddt_type type = 0; type < DDT_TYPES; type++) {
uint64_t add, count = 0;
for (enum ddt_class class = 0; class < DDT_CLASSES; class++) {
if (ddt_object_exists(ddt, type, class)) {
ddt_object_sync(ddt, type, class, tx);
VERIFY(ddt_object_count(ddt, type, class,
&add) == 0);
count += add;
}
}
for (enum ddt_class class = 0; class < DDT_CLASSES; class++) {
if (count == 0 && ddt_object_exists(ddt, type, class))
ddt_object_destroy(ddt, type, class, tx);
}
}
bcopy(ddt->ddt_histogram, &ddt->ddt_histogram_cache,
sizeof (ddt->ddt_histogram));
spa->spa_dedup_dspace = ~0ULL;
}
void
ddt_sync(spa_t *spa, uint64_t txg)
{
dsl_scan_t *scn = spa->spa_dsl_pool->dp_scan;
dmu_tx_t *tx;
zio_t *rio;
ASSERT(spa_syncing_txg(spa) == txg);
tx = dmu_tx_create_assigned(spa->spa_dsl_pool, txg);
rio = zio_root(spa, NULL, NULL,
ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE | ZIO_FLAG_SELF_HEAL);
/*
* This function may cause an immediate scan of ddt blocks (see
* the comment above dsl_scan_ddt() for details). We set the
* scan's root zio here so that we can wait for any scan IOs in
* addition to the regular ddt IOs.
*/
ASSERT3P(scn->scn_zio_root, ==, NULL);
scn->scn_zio_root = rio;
for (enum zio_checksum c = 0; c < ZIO_CHECKSUM_FUNCTIONS; c++) {
ddt_t *ddt = spa->spa_ddt[c];
if (ddt == NULL)
continue;
ddt_sync_table(ddt, tx, txg);
ddt_repair_table(ddt, rio);
}
(void) zio_wait(rio);
scn->scn_zio_root = NULL;
dmu_tx_commit(tx);
}
int
ddt_walk(spa_t *spa, ddt_bookmark_t *ddb, ddt_entry_t *dde)
{
do {
do {
do {
ddt_t *ddt = spa->spa_ddt[ddb->ddb_checksum];
int error = ENOENT;
if (ddt_object_exists(ddt, ddb->ddb_type,
ddb->ddb_class)) {
error = ddt_object_walk(ddt,
ddb->ddb_type, ddb->ddb_class,
&ddb->ddb_cursor, dde);
}
dde->dde_type = ddb->ddb_type;
dde->dde_class = ddb->ddb_class;
if (error == 0)
return (0);
if (error != ENOENT)
return (error);
ddb->ddb_cursor = 0;
} while (++ddb->ddb_checksum < ZIO_CHECKSUM_FUNCTIONS);
ddb->ddb_checksum = 0;
} while (++ddb->ddb_type < DDT_TYPES);
ddb->ddb_type = 0;
} while (++ddb->ddb_class < DDT_CLASSES);
return (SET_ERROR(ENOENT));
}
/* BEGIN CSTYLED */
ZFS_MODULE_PARAM(zfs, zfs_, dedup_prefetch, INT, ZMOD_RW,
"Enable prefetching dedup-ed blks");
/* END CSTYLED */