mirror_zfs/module/zfs/dmu.c
Brian Behlendorf 6149f4c45f Remove dmu_write_pages() support
For the moment we do not use dmu_write_pages() to write pages
directly in to a dmu object.  It may be required at some point
in the future, but for now is simplest and cleanest to drop it.
It can be easily readded if/when needed.
2011-02-10 09:27:21 -08:00

1900 lines
43 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
*/
#include <sys/dmu.h>
#include <sys/dmu_impl.h>
#include <sys/dmu_tx.h>
#include <sys/dbuf.h>
#include <sys/dnode.h>
#include <sys/zfs_context.h>
#include <sys/dmu_objset.h>
#include <sys/dmu_traverse.h>
#include <sys/dsl_dataset.h>
#include <sys/dsl_dir.h>
#include <sys/dsl_pool.h>
#include <sys/dsl_synctask.h>
#include <sys/dsl_prop.h>
#include <sys/dmu_zfetch.h>
#include <sys/zfs_ioctl.h>
#include <sys/zap.h>
#include <sys/zio_checksum.h>
#include <sys/sa.h>
#ifdef _KERNEL
#include <sys/vmsystm.h>
#include <sys/zfs_znode.h>
#endif
const dmu_object_type_info_t dmu_ot[DMU_OT_NUMTYPES] = {
{ byteswap_uint8_array, TRUE, "unallocated" },
{ zap_byteswap, TRUE, "object directory" },
{ byteswap_uint64_array, TRUE, "object array" },
{ byteswap_uint8_array, TRUE, "packed nvlist" },
{ byteswap_uint64_array, TRUE, "packed nvlist size" },
{ byteswap_uint64_array, TRUE, "bpobj" },
{ byteswap_uint64_array, TRUE, "bpobj header" },
{ byteswap_uint64_array, TRUE, "SPA space map header" },
{ byteswap_uint64_array, TRUE, "SPA space map" },
{ byteswap_uint64_array, TRUE, "ZIL intent log" },
{ dnode_buf_byteswap, TRUE, "DMU dnode" },
{ dmu_objset_byteswap, TRUE, "DMU objset" },
{ byteswap_uint64_array, TRUE, "DSL directory" },
{ zap_byteswap, TRUE, "DSL directory child map"},
{ zap_byteswap, TRUE, "DSL dataset snap map" },
{ zap_byteswap, TRUE, "DSL props" },
{ byteswap_uint64_array, TRUE, "DSL dataset" },
{ zfs_znode_byteswap, TRUE, "ZFS znode" },
{ zfs_oldacl_byteswap, TRUE, "ZFS V0 ACL" },
{ byteswap_uint8_array, FALSE, "ZFS plain file" },
{ zap_byteswap, TRUE, "ZFS directory" },
{ zap_byteswap, TRUE, "ZFS master node" },
{ zap_byteswap, TRUE, "ZFS delete queue" },
{ byteswap_uint8_array, FALSE, "zvol object" },
{ zap_byteswap, TRUE, "zvol prop" },
{ byteswap_uint8_array, FALSE, "other uint8[]" },
{ byteswap_uint64_array, FALSE, "other uint64[]" },
{ zap_byteswap, TRUE, "other ZAP" },
{ zap_byteswap, TRUE, "persistent error log" },
{ byteswap_uint8_array, TRUE, "SPA history" },
{ byteswap_uint64_array, TRUE, "SPA history offsets" },
{ zap_byteswap, TRUE, "Pool properties" },
{ zap_byteswap, TRUE, "DSL permissions" },
{ zfs_acl_byteswap, TRUE, "ZFS ACL" },
{ byteswap_uint8_array, TRUE, "ZFS SYSACL" },
{ byteswap_uint8_array, TRUE, "FUID table" },
{ byteswap_uint64_array, TRUE, "FUID table size" },
{ zap_byteswap, TRUE, "DSL dataset next clones"},
{ zap_byteswap, TRUE, "scan work queue" },
{ zap_byteswap, TRUE, "ZFS user/group used" },
{ zap_byteswap, TRUE, "ZFS user/group quota" },
{ zap_byteswap, TRUE, "snapshot refcount tags"},
{ zap_byteswap, TRUE, "DDT ZAP algorithm" },
{ zap_byteswap, TRUE, "DDT statistics" },
{ byteswap_uint8_array, TRUE, "System attributes" },
{ zap_byteswap, TRUE, "SA master node" },
{ zap_byteswap, TRUE, "SA attr registration" },
{ zap_byteswap, TRUE, "SA attr layouts" },
{ zap_byteswap, TRUE, "scan translations" },
{ byteswap_uint8_array, FALSE, "deduplicated block" },
{ zap_byteswap, TRUE, "DSL deadlist map" },
{ byteswap_uint64_array, TRUE, "DSL deadlist map hdr" },
{ zap_byteswap, TRUE, "DSL dir clones" },
{ byteswap_uint64_array, TRUE, "bpobj subobj" },
};
int
dmu_buf_hold(objset_t *os, uint64_t object, uint64_t offset,
void *tag, dmu_buf_t **dbp, int flags)
{
dnode_t *dn;
uint64_t blkid;
dmu_buf_impl_t *db;
int err;
int db_flags = DB_RF_CANFAIL;
if (flags & DMU_READ_NO_PREFETCH)
db_flags |= DB_RF_NOPREFETCH;
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
blkid = dbuf_whichblock(dn, offset);
rw_enter(&dn->dn_struct_rwlock, RW_READER);
db = dbuf_hold(dn, blkid, tag);
rw_exit(&dn->dn_struct_rwlock);
if (db == NULL) {
err = EIO;
} else {
err = dbuf_read(db, NULL, db_flags);
if (err) {
dbuf_rele(db, tag);
db = NULL;
}
}
dnode_rele(dn, FTAG);
*dbp = &db->db; /* NULL db plus first field offset is NULL */
return (err);
}
int
dmu_bonus_max(void)
{
return (DN_MAX_BONUSLEN);
}
int
dmu_set_bonus(dmu_buf_t *db_fake, int newsize, dmu_tx_t *tx)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
dnode_t *dn;
int error;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
if (dn->dn_bonus != db) {
error = EINVAL;
} else if (newsize < 0 || newsize > db_fake->db_size) {
error = EINVAL;
} else {
dnode_setbonuslen(dn, newsize, tx);
error = 0;
}
DB_DNODE_EXIT(db);
return (error);
}
int
dmu_set_bonustype(dmu_buf_t *db_fake, dmu_object_type_t type, dmu_tx_t *tx)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
dnode_t *dn;
int error;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
if (type > DMU_OT_NUMTYPES) {
error = EINVAL;
} else if (dn->dn_bonus != db) {
error = EINVAL;
} else {
dnode_setbonus_type(dn, type, tx);
error = 0;
}
DB_DNODE_EXIT(db);
return (error);
}
dmu_object_type_t
dmu_get_bonustype(dmu_buf_t *db_fake)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
dnode_t *dn;
dmu_object_type_t type;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
type = dn->dn_bonustype;
DB_DNODE_EXIT(db);
return (type);
}
int
dmu_rm_spill(objset_t *os, uint64_t object, dmu_tx_t *tx)
{
dnode_t *dn;
int error;
error = dnode_hold(os, object, FTAG, &dn);
dbuf_rm_spill(dn, tx);
rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
dnode_rm_spill(dn, tx);
rw_exit(&dn->dn_struct_rwlock);
dnode_rele(dn, FTAG);
return (error);
}
/*
* returns ENOENT, EIO, or 0.
*/
int
dmu_bonus_hold(objset_t *os, uint64_t object, void *tag, dmu_buf_t **dbp)
{
dnode_t *dn;
dmu_buf_impl_t *db;
int error;
error = dnode_hold(os, object, FTAG, &dn);
if (error)
return (error);
rw_enter(&dn->dn_struct_rwlock, RW_READER);
if (dn->dn_bonus == NULL) {
rw_exit(&dn->dn_struct_rwlock);
rw_enter(&dn->dn_struct_rwlock, RW_WRITER);
if (dn->dn_bonus == NULL)
dbuf_create_bonus(dn);
}
db = dn->dn_bonus;
/* as long as the bonus buf is held, the dnode will be held */
if (refcount_add(&db->db_holds, tag) == 1) {
VERIFY(dnode_add_ref(dn, db));
(void) atomic_inc_32_nv(&dn->dn_dbufs_count);
}
/*
* Wait to drop dn_struct_rwlock until after adding the bonus dbuf's
* hold and incrementing the dbuf count to ensure that dnode_move() sees
* a dnode hold for every dbuf.
*/
rw_exit(&dn->dn_struct_rwlock);
dnode_rele(dn, FTAG);
VERIFY(0 == dbuf_read(db, NULL, DB_RF_MUST_SUCCEED | DB_RF_NOPREFETCH));
*dbp = &db->db;
return (0);
}
/*
* returns ENOENT, EIO, or 0.
*
* This interface will allocate a blank spill dbuf when a spill blk
* doesn't already exist on the dnode.
*
* if you only want to find an already existing spill db, then
* dmu_spill_hold_existing() should be used.
*/
int
dmu_spill_hold_by_dnode(dnode_t *dn, uint32_t flags, void *tag, dmu_buf_t **dbp)
{
dmu_buf_impl_t *db = NULL;
int err;
if ((flags & DB_RF_HAVESTRUCT) == 0)
rw_enter(&dn->dn_struct_rwlock, RW_READER);
db = dbuf_hold(dn, DMU_SPILL_BLKID, tag);
if ((flags & DB_RF_HAVESTRUCT) == 0)
rw_exit(&dn->dn_struct_rwlock);
ASSERT(db != NULL);
err = dbuf_read(db, NULL, flags);
if (err == 0)
*dbp = &db->db;
else
dbuf_rele(db, tag);
return (err);
}
int
dmu_spill_hold_existing(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
dnode_t *dn;
int err;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
if (spa_version(dn->dn_objset->os_spa) < SPA_VERSION_SA) {
err = EINVAL;
} else {
rw_enter(&dn->dn_struct_rwlock, RW_READER);
if (!dn->dn_have_spill) {
err = ENOENT;
} else {
err = dmu_spill_hold_by_dnode(dn,
DB_RF_HAVESTRUCT | DB_RF_CANFAIL, tag, dbp);
}
rw_exit(&dn->dn_struct_rwlock);
}
DB_DNODE_EXIT(db);
return (err);
}
int
dmu_spill_hold_by_bonus(dmu_buf_t *bonus, void *tag, dmu_buf_t **dbp)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)bonus;
dnode_t *dn;
int err;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
err = dmu_spill_hold_by_dnode(dn, DB_RF_CANFAIL, tag, dbp);
DB_DNODE_EXIT(db);
return (err);
}
/*
* Note: longer-term, we should modify all of the dmu_buf_*() interfaces
* to take a held dnode rather than <os, object> -- the lookup is wasteful,
* and can induce severe lock contention when writing to several files
* whose dnodes are in the same block.
*/
static int
dmu_buf_hold_array_by_dnode(dnode_t *dn, uint64_t offset, uint64_t length,
int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp, uint32_t flags)
{
dsl_pool_t *dp = NULL;
dmu_buf_t **dbp;
uint64_t blkid, nblks, i;
uint32_t dbuf_flags;
int err;
zio_t *zio;
hrtime_t start = 0;
ASSERT(length <= DMU_MAX_ACCESS);
dbuf_flags = DB_RF_CANFAIL | DB_RF_NEVERWAIT | DB_RF_HAVESTRUCT;
if (flags & DMU_READ_NO_PREFETCH || length > zfetch_array_rd_sz)
dbuf_flags |= DB_RF_NOPREFETCH;
rw_enter(&dn->dn_struct_rwlock, RW_READER);
if (dn->dn_datablkshift) {
int blkshift = dn->dn_datablkshift;
nblks = (P2ROUNDUP(offset+length, 1ULL<<blkshift) -
P2ALIGN(offset, 1ULL<<blkshift)) >> blkshift;
} else {
if (offset + length > dn->dn_datablksz) {
zfs_panic_recover("zfs: accessing past end of object "
"%llx/%llx (size=%u access=%llu+%llu)",
(longlong_t)dn->dn_objset->
os_dsl_dataset->ds_object,
(longlong_t)dn->dn_object, dn->dn_datablksz,
(longlong_t)offset, (longlong_t)length);
rw_exit(&dn->dn_struct_rwlock);
return (EIO);
}
nblks = 1;
}
dbp = kmem_zalloc(sizeof (dmu_buf_t *) * nblks, KM_SLEEP);
if (dn->dn_objset->os_dsl_dataset)
dp = dn->dn_objset->os_dsl_dataset->ds_dir->dd_pool;
if (dp && dsl_pool_sync_context(dp))
start = gethrtime();
zio = zio_root(dn->dn_objset->os_spa, NULL, NULL, ZIO_FLAG_CANFAIL);
blkid = dbuf_whichblock(dn, offset);
for (i = 0; i < nblks; i++) {
dmu_buf_impl_t *db = dbuf_hold(dn, blkid+i, tag);
if (db == NULL) {
rw_exit(&dn->dn_struct_rwlock);
dmu_buf_rele_array(dbp, nblks, tag);
zio_nowait(zio);
return (EIO);
}
/* initiate async i/o */
if (read) {
(void) dbuf_read(db, zio, dbuf_flags);
}
dbp[i] = &db->db;
}
rw_exit(&dn->dn_struct_rwlock);
/* wait for async i/o */
err = zio_wait(zio);
/* track read overhead when we are in sync context */
if (dp && dsl_pool_sync_context(dp))
dp->dp_read_overhead += gethrtime() - start;
if (err) {
dmu_buf_rele_array(dbp, nblks, tag);
return (err);
}
/* wait for other io to complete */
if (read) {
for (i = 0; i < nblks; i++) {
dmu_buf_impl_t *db = (dmu_buf_impl_t *)dbp[i];
mutex_enter(&db->db_mtx);
while (db->db_state == DB_READ ||
db->db_state == DB_FILL)
cv_wait(&db->db_changed, &db->db_mtx);
if (db->db_state == DB_UNCACHED)
err = EIO;
mutex_exit(&db->db_mtx);
if (err) {
dmu_buf_rele_array(dbp, nblks, tag);
return (err);
}
}
}
*numbufsp = nblks;
*dbpp = dbp;
return (0);
}
static int
dmu_buf_hold_array(objset_t *os, uint64_t object, uint64_t offset,
uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
{
dnode_t *dn;
int err;
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
numbufsp, dbpp, DMU_READ_PREFETCH);
dnode_rele(dn, FTAG);
return (err);
}
int
dmu_buf_hold_array_by_bonus(dmu_buf_t *db_fake, uint64_t offset,
uint64_t length, int read, void *tag, int *numbufsp, dmu_buf_t ***dbpp)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
dnode_t *dn;
int err;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
err = dmu_buf_hold_array_by_dnode(dn, offset, length, read, tag,
numbufsp, dbpp, DMU_READ_PREFETCH);
DB_DNODE_EXIT(db);
return (err);
}
void
dmu_buf_rele_array(dmu_buf_t **dbp_fake, int numbufs, void *tag)
{
int i;
dmu_buf_impl_t **dbp = (dmu_buf_impl_t **)dbp_fake;
if (numbufs == 0)
return;
for (i = 0; i < numbufs; i++) {
if (dbp[i])
dbuf_rele(dbp[i], tag);
}
kmem_free(dbp, sizeof (dmu_buf_t *) * numbufs);
}
void
dmu_prefetch(objset_t *os, uint64_t object, uint64_t offset, uint64_t len)
{
dnode_t *dn;
uint64_t blkid;
int nblks, i, err;
if (zfs_prefetch_disable)
return;
if (len == 0) { /* they're interested in the bonus buffer */
dn = DMU_META_DNODE(os);
if (object == 0 || object >= DN_MAX_OBJECT)
return;
rw_enter(&dn->dn_struct_rwlock, RW_READER);
blkid = dbuf_whichblock(dn, object * sizeof (dnode_phys_t));
dbuf_prefetch(dn, blkid);
rw_exit(&dn->dn_struct_rwlock);
return;
}
/*
* XXX - Note, if the dnode for the requested object is not
* already cached, we will do a *synchronous* read in the
* dnode_hold() call. The same is true for any indirects.
*/
err = dnode_hold(os, object, FTAG, &dn);
if (err != 0)
return;
rw_enter(&dn->dn_struct_rwlock, RW_READER);
if (dn->dn_datablkshift) {
int blkshift = dn->dn_datablkshift;
nblks = (P2ROUNDUP(offset+len, 1<<blkshift) -
P2ALIGN(offset, 1<<blkshift)) >> blkshift;
} else {
nblks = (offset < dn->dn_datablksz);
}
if (nblks != 0) {
blkid = dbuf_whichblock(dn, offset);
for (i = 0; i < nblks; i++)
dbuf_prefetch(dn, blkid+i);
}
rw_exit(&dn->dn_struct_rwlock);
dnode_rele(dn, FTAG);
}
/*
* Get the next "chunk" of file data to free. We traverse the file from
* the end so that the file gets shorter over time (if we crashes in the
* middle, this will leave us in a better state). We find allocated file
* data by simply searching the allocated level 1 indirects.
*/
static int
get_next_chunk(dnode_t *dn, uint64_t *start, uint64_t limit)
{
uint64_t len = *start - limit;
uint64_t blkcnt = 0;
uint64_t maxblks = DMU_MAX_ACCESS / (1ULL << (dn->dn_indblkshift + 1));
uint64_t iblkrange =
dn->dn_datablksz * EPB(dn->dn_indblkshift, SPA_BLKPTRSHIFT);
ASSERT(limit <= *start);
if (len <= iblkrange * maxblks) {
*start = limit;
return (0);
}
ASSERT(ISP2(iblkrange));
while (*start > limit && blkcnt < maxblks) {
int err;
/* find next allocated L1 indirect */
err = dnode_next_offset(dn,
DNODE_FIND_BACKWARDS, start, 2, 1, 0);
/* if there are no more, then we are done */
if (err == ESRCH) {
*start = limit;
return (0);
} else if (err) {
return (err);
}
blkcnt += 1;
/* reset offset to end of "next" block back */
*start = P2ALIGN(*start, iblkrange);
if (*start <= limit)
*start = limit;
else
*start -= 1;
}
return (0);
}
static int
dmu_free_long_range_impl(objset_t *os, dnode_t *dn, uint64_t offset,
uint64_t length, boolean_t free_dnode)
{
dmu_tx_t *tx;
uint64_t object_size, start, end, len;
boolean_t trunc = (length == DMU_OBJECT_END);
int align, err;
align = 1 << dn->dn_datablkshift;
ASSERT(align > 0);
object_size = align == 1 ? dn->dn_datablksz :
(dn->dn_maxblkid + 1) << dn->dn_datablkshift;
end = offset + length;
if (trunc || end > object_size)
end = object_size;
if (end <= offset)
return (0);
length = end - offset;
while (length) {
start = end;
/* assert(offset <= start) */
err = get_next_chunk(dn, &start, offset);
if (err)
return (err);
len = trunc ? DMU_OBJECT_END : end - start;
tx = dmu_tx_create(os);
dmu_tx_hold_free(tx, dn->dn_object, start, len);
err = dmu_tx_assign(tx, TXG_WAIT);
if (err) {
dmu_tx_abort(tx);
return (err);
}
dnode_free_range(dn, start, trunc ? -1 : len, tx);
if (start == 0 && free_dnode) {
ASSERT(trunc);
dnode_free(dn, tx);
}
length -= end - start;
dmu_tx_commit(tx);
end = start;
}
return (0);
}
int
dmu_free_long_range(objset_t *os, uint64_t object,
uint64_t offset, uint64_t length)
{
dnode_t *dn;
int err;
err = dnode_hold(os, object, FTAG, &dn);
if (err != 0)
return (err);
err = dmu_free_long_range_impl(os, dn, offset, length, FALSE);
dnode_rele(dn, FTAG);
return (err);
}
int
dmu_free_object(objset_t *os, uint64_t object)
{
dnode_t *dn;
dmu_tx_t *tx;
int err;
err = dnode_hold_impl(os, object, DNODE_MUST_BE_ALLOCATED,
FTAG, &dn);
if (err != 0)
return (err);
if (dn->dn_nlevels == 1) {
tx = dmu_tx_create(os);
dmu_tx_hold_bonus(tx, object);
dmu_tx_hold_free(tx, dn->dn_object, 0, DMU_OBJECT_END);
err = dmu_tx_assign(tx, TXG_WAIT);
if (err == 0) {
dnode_free_range(dn, 0, DMU_OBJECT_END, tx);
dnode_free(dn, tx);
dmu_tx_commit(tx);
} else {
dmu_tx_abort(tx);
}
} else {
err = dmu_free_long_range_impl(os, dn, 0, DMU_OBJECT_END, TRUE);
}
dnode_rele(dn, FTAG);
return (err);
}
int
dmu_free_range(objset_t *os, uint64_t object, uint64_t offset,
uint64_t size, dmu_tx_t *tx)
{
dnode_t *dn;
int err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
ASSERT(offset < UINT64_MAX);
ASSERT(size == -1ULL || size <= UINT64_MAX - offset);
dnode_free_range(dn, offset, size, tx);
dnode_rele(dn, FTAG);
return (0);
}
int
dmu_read(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
void *buf, uint32_t flags)
{
dnode_t *dn;
dmu_buf_t **dbp;
int numbufs, err;
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
/*
* Deal with odd block sizes, where there can't be data past the first
* block. If we ever do the tail block optimization, we will need to
* handle that here as well.
*/
if (dn->dn_maxblkid == 0) {
int newsz = offset > dn->dn_datablksz ? 0 :
MIN(size, dn->dn_datablksz - offset);
bzero((char *)buf + newsz, size - newsz);
size = newsz;
}
while (size > 0) {
uint64_t mylen = MIN(size, DMU_MAX_ACCESS / 2);
int i;
/*
* NB: we could do this block-at-a-time, but it's nice
* to be reading in parallel.
*/
err = dmu_buf_hold_array_by_dnode(dn, offset, mylen,
TRUE, FTAG, &numbufs, &dbp, flags);
if (err)
break;
for (i = 0; i < numbufs; i++) {
int tocpy;
int bufoff;
dmu_buf_t *db = dbp[i];
ASSERT(size > 0);
bufoff = offset - db->db_offset;
tocpy = (int)MIN(db->db_size - bufoff, size);
bcopy((char *)db->db_data + bufoff, buf, tocpy);
offset += tocpy;
size -= tocpy;
buf = (char *)buf + tocpy;
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
}
dnode_rele(dn, FTAG);
return (err);
}
void
dmu_write(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
const void *buf, dmu_tx_t *tx)
{
dmu_buf_t **dbp;
int numbufs, i;
if (size == 0)
return;
VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
FALSE, FTAG, &numbufs, &dbp));
for (i = 0; i < numbufs; i++) {
int tocpy;
int bufoff;
dmu_buf_t *db = dbp[i];
ASSERT(size > 0);
bufoff = offset - db->db_offset;
tocpy = (int)MIN(db->db_size - bufoff, size);
ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
if (tocpy == db->db_size)
dmu_buf_will_fill(db, tx);
else
dmu_buf_will_dirty(db, tx);
(void) memcpy((char *)db->db_data + bufoff, buf, tocpy);
if (tocpy == db->db_size)
dmu_buf_fill_done(db, tx);
offset += tocpy;
size -= tocpy;
buf = (char *)buf + tocpy;
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
}
void
dmu_prealloc(objset_t *os, uint64_t object, uint64_t offset, uint64_t size,
dmu_tx_t *tx)
{
dmu_buf_t **dbp;
int numbufs, i;
if (size == 0)
return;
VERIFY(0 == dmu_buf_hold_array(os, object, offset, size,
FALSE, FTAG, &numbufs, &dbp));
for (i = 0; i < numbufs; i++) {
dmu_buf_t *db = dbp[i];
dmu_buf_will_not_fill(db, tx);
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
}
/*
* DMU support for xuio
*/
kstat_t *xuio_ksp = NULL;
typedef struct xuio_stats {
/* loaned yet not returned arc_buf */
kstat_named_t xuiostat_onloan_rbuf;
kstat_named_t xuiostat_onloan_wbuf;
/* whether a copy is made when loaning out a read buffer */
kstat_named_t xuiostat_rbuf_copied;
kstat_named_t xuiostat_rbuf_nocopy;
/* whether a copy is made when assigning a write buffer */
kstat_named_t xuiostat_wbuf_copied;
kstat_named_t xuiostat_wbuf_nocopy;
} xuio_stats_t;
static xuio_stats_t xuio_stats = {
{ "onloan_read_buf", KSTAT_DATA_UINT64 },
{ "onloan_write_buf", KSTAT_DATA_UINT64 },
{ "read_buf_copied", KSTAT_DATA_UINT64 },
{ "read_buf_nocopy", KSTAT_DATA_UINT64 },
{ "write_buf_copied", KSTAT_DATA_UINT64 },
{ "write_buf_nocopy", KSTAT_DATA_UINT64 }
};
#define XUIOSTAT_INCR(stat, val) \
atomic_add_64(&xuio_stats.stat.value.ui64, (val))
#define XUIOSTAT_BUMP(stat) XUIOSTAT_INCR(stat, 1)
int
dmu_xuio_init(xuio_t *xuio, int nblk)
{
dmu_xuio_t *priv;
uio_t *uio = &xuio->xu_uio;
uio->uio_iovcnt = nblk;
uio->uio_iov = kmem_zalloc(nblk * sizeof (iovec_t), KM_SLEEP);
priv = kmem_zalloc(sizeof (dmu_xuio_t), KM_SLEEP);
priv->cnt = nblk;
priv->bufs = kmem_zalloc(nblk * sizeof (arc_buf_t *), KM_SLEEP);
priv->iovp = uio->uio_iov;
XUIO_XUZC_PRIV(xuio) = priv;
if (XUIO_XUZC_RW(xuio) == UIO_READ)
XUIOSTAT_INCR(xuiostat_onloan_rbuf, nblk);
else
XUIOSTAT_INCR(xuiostat_onloan_wbuf, nblk);
return (0);
}
void
dmu_xuio_fini(xuio_t *xuio)
{
dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
int nblk = priv->cnt;
kmem_free(priv->iovp, nblk * sizeof (iovec_t));
kmem_free(priv->bufs, nblk * sizeof (arc_buf_t *));
kmem_free(priv, sizeof (dmu_xuio_t));
if (XUIO_XUZC_RW(xuio) == UIO_READ)
XUIOSTAT_INCR(xuiostat_onloan_rbuf, -nblk);
else
XUIOSTAT_INCR(xuiostat_onloan_wbuf, -nblk);
}
/*
* Initialize iov[priv->next] and priv->bufs[priv->next] with { off, n, abuf }
* and increase priv->next by 1.
*/
int
dmu_xuio_add(xuio_t *xuio, arc_buf_t *abuf, offset_t off, size_t n)
{
struct iovec *iov;
uio_t *uio = &xuio->xu_uio;
dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
int i = priv->next++;
ASSERT(i < priv->cnt);
ASSERT(off + n <= arc_buf_size(abuf));
iov = uio->uio_iov + i;
iov->iov_base = (char *)abuf->b_data + off;
iov->iov_len = n;
priv->bufs[i] = abuf;
return (0);
}
int
dmu_xuio_cnt(xuio_t *xuio)
{
dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
return (priv->cnt);
}
arc_buf_t *
dmu_xuio_arcbuf(xuio_t *xuio, int i)
{
dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
ASSERT(i < priv->cnt);
return (priv->bufs[i]);
}
void
dmu_xuio_clear(xuio_t *xuio, int i)
{
dmu_xuio_t *priv = XUIO_XUZC_PRIV(xuio);
ASSERT(i < priv->cnt);
priv->bufs[i] = NULL;
}
static void
xuio_stat_init(void)
{
xuio_ksp = kstat_create("zfs", 0, "xuio_stats", "misc",
KSTAT_TYPE_NAMED, sizeof (xuio_stats) / sizeof (kstat_named_t),
KSTAT_FLAG_VIRTUAL);
if (xuio_ksp != NULL) {
xuio_ksp->ks_data = &xuio_stats;
kstat_install(xuio_ksp);
}
}
static void
xuio_stat_fini(void)
{
if (xuio_ksp != NULL) {
kstat_delete(xuio_ksp);
xuio_ksp = NULL;
}
}
void
xuio_stat_wbuf_copied()
{
XUIOSTAT_BUMP(xuiostat_wbuf_copied);
}
void
xuio_stat_wbuf_nocopy()
{
XUIOSTAT_BUMP(xuiostat_wbuf_nocopy);
}
#ifdef _KERNEL
/*
* Copy up to size bytes between arg_buf and req based on the data direction
* described by the req. If an entire req's data cannot be transfered the
* req's is updated such that it's current index and bv offsets correctly
* reference any residual data which could not be copied. The return value
* is the number of bytes successfully copied to arg_buf.
*/
static int
dmu_req_copy(void *arg_buf, int size, int *offset, struct request *req)
{
struct bio_vec *bv;
struct req_iterator iter;
char *bv_buf;
int tocpy;
*offset = 0;
rq_for_each_segment(bv, req, iter) {
/* Fully consumed the passed arg_buf */
ASSERT3S(*offset, <=, size);
if (size == *offset)
break;
/* Skip fully consumed bv's */
if (bv->bv_len == 0)
continue;
tocpy = MIN(bv->bv_len, size - *offset);
ASSERT3S(tocpy, >=, 0);
bv_buf = page_address(bv->bv_page) + bv->bv_offset;
ASSERT3P(bv_buf, !=, NULL);
if (rq_data_dir(req) == WRITE)
memcpy(arg_buf + *offset, bv_buf, tocpy);
else
memcpy(bv_buf, arg_buf + *offset, tocpy);
*offset += tocpy;
bv->bv_offset += tocpy;
bv->bv_len -= tocpy;
}
return 0;
}
int
dmu_read_req(objset_t *os, uint64_t object, struct request *req)
{
uint64_t size = blk_rq_bytes(req);
uint64_t offset = blk_rq_pos(req) << 9;
dmu_buf_t **dbp;
int numbufs, i, err;
/*
* NB: we could do this block-at-a-time, but it's nice
* to be reading in parallel.
*/
err = dmu_buf_hold_array(os, object, offset, size, TRUE, FTAG,
&numbufs, &dbp);
if (err)
return (err);
for (i = 0; i < numbufs; i++) {
int tocpy, didcpy, bufoff;
dmu_buf_t *db = dbp[i];
bufoff = offset - db->db_offset;
ASSERT3S(bufoff, >=, 0);
tocpy = (int)MIN(db->db_size - bufoff, size);
if (tocpy == 0)
break;
err = dmu_req_copy(db->db_data + bufoff, tocpy, &didcpy, req);
if (didcpy < tocpy)
err = EIO;
if (err)
break;
size -= tocpy;
offset += didcpy;
err = 0;
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
return (err);
}
int
dmu_write_req(objset_t *os, uint64_t object, struct request *req, dmu_tx_t *tx)
{
uint64_t size = blk_rq_bytes(req);
uint64_t offset = blk_rq_pos(req) << 9;
dmu_buf_t **dbp;
int numbufs;
int err = 0;
int i;
if (size == 0)
return (0);
err = dmu_buf_hold_array(os, object, offset, size, FALSE, FTAG,
&numbufs, &dbp);
if (err)
return (err);
for (i = 0; i < numbufs; i++) {
int tocpy, didcpy, bufoff;
dmu_buf_t *db = dbp[i];
bufoff = offset - db->db_offset;
ASSERT3S(bufoff, >=, 0);
tocpy = (int)MIN(db->db_size - bufoff, size);
if (tocpy == 0)
break;
ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
if (tocpy == db->db_size)
dmu_buf_will_fill(db, tx);
else
dmu_buf_will_dirty(db, tx);
err = dmu_req_copy(db->db_data + bufoff, tocpy, &didcpy, req);
if (tocpy == db->db_size)
dmu_buf_fill_done(db, tx);
if (didcpy < tocpy)
err = EIO;
if (err)
break;
size -= tocpy;
offset += didcpy;
err = 0;
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
return (err);
}
int
dmu_read_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size)
{
dmu_buf_t **dbp;
int numbufs, i, err;
xuio_t *xuio = NULL;
/*
* NB: we could do this block-at-a-time, but it's nice
* to be reading in parallel.
*/
err = dmu_buf_hold_array(os, object, uio->uio_loffset, size, TRUE, FTAG,
&numbufs, &dbp);
if (err)
return (err);
for (i = 0; i < numbufs; i++) {
int tocpy;
int bufoff;
dmu_buf_t *db = dbp[i];
ASSERT(size > 0);
bufoff = uio->uio_loffset - db->db_offset;
tocpy = (int)MIN(db->db_size - bufoff, size);
if (xuio) {
dmu_buf_impl_t *dbi = (dmu_buf_impl_t *)db;
arc_buf_t *dbuf_abuf = dbi->db_buf;
arc_buf_t *abuf = dbuf_loan_arcbuf(dbi);
err = dmu_xuio_add(xuio, abuf, bufoff, tocpy);
if (!err) {
uio->uio_resid -= tocpy;
uio->uio_loffset += tocpy;
}
if (abuf == dbuf_abuf)
XUIOSTAT_BUMP(xuiostat_rbuf_nocopy);
else
XUIOSTAT_BUMP(xuiostat_rbuf_copied);
} else {
err = uiomove((char *)db->db_data + bufoff, tocpy,
UIO_READ, uio);
}
if (err)
break;
size -= tocpy;
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
return (err);
}
static int
dmu_write_uio_dnode(dnode_t *dn, uio_t *uio, uint64_t size, dmu_tx_t *tx)
{
dmu_buf_t **dbp;
int numbufs;
int err = 0;
int i;
err = dmu_buf_hold_array_by_dnode(dn, uio->uio_loffset, size,
FALSE, FTAG, &numbufs, &dbp, DMU_READ_PREFETCH);
if (err)
return (err);
for (i = 0; i < numbufs; i++) {
int tocpy;
int bufoff;
dmu_buf_t *db = dbp[i];
ASSERT(size > 0);
bufoff = uio->uio_loffset - db->db_offset;
tocpy = (int)MIN(db->db_size - bufoff, size);
ASSERT(i == 0 || i == numbufs-1 || tocpy == db->db_size);
if (tocpy == db->db_size)
dmu_buf_will_fill(db, tx);
else
dmu_buf_will_dirty(db, tx);
/*
* XXX uiomove could block forever (eg.nfs-backed
* pages). There needs to be a uiolockdown() function
* to lock the pages in memory, so that uiomove won't
* block.
*/
err = uiomove((char *)db->db_data + bufoff, tocpy,
UIO_WRITE, uio);
if (tocpy == db->db_size)
dmu_buf_fill_done(db, tx);
if (err)
break;
size -= tocpy;
}
dmu_buf_rele_array(dbp, numbufs, FTAG);
return (err);
}
int
dmu_write_uio_dbuf(dmu_buf_t *zdb, uio_t *uio, uint64_t size,
dmu_tx_t *tx)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)zdb;
dnode_t *dn;
int err;
if (size == 0)
return (0);
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
err = dmu_write_uio_dnode(dn, uio, size, tx);
DB_DNODE_EXIT(db);
return (err);
}
int
dmu_write_uio(objset_t *os, uint64_t object, uio_t *uio, uint64_t size,
dmu_tx_t *tx)
{
dnode_t *dn;
int err;
if (size == 0)
return (0);
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
err = dmu_write_uio_dnode(dn, uio, size, tx);
dnode_rele(dn, FTAG);
return (err);
}
#endif /* _KERNEL */
/*
* Allocate a loaned anonymous arc buffer.
*/
arc_buf_t *
dmu_request_arcbuf(dmu_buf_t *handle, int size)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)handle;
spa_t *spa;
DB_GET_SPA(&spa, db);
return (arc_loan_buf(spa, size));
}
/*
* Free a loaned arc buffer.
*/
void
dmu_return_arcbuf(arc_buf_t *buf)
{
arc_return_buf(buf, FTAG);
VERIFY(arc_buf_remove_ref(buf, FTAG) == 1);
}
/*
* When possible directly assign passed loaned arc buffer to a dbuf.
* If this is not possible copy the contents of passed arc buf via
* dmu_write().
*/
void
dmu_assign_arcbuf(dmu_buf_t *handle, uint64_t offset, arc_buf_t *buf,
dmu_tx_t *tx)
{
dmu_buf_impl_t *dbuf = (dmu_buf_impl_t *)handle;
dnode_t *dn;
dmu_buf_impl_t *db;
uint32_t blksz = (uint32_t)arc_buf_size(buf);
uint64_t blkid;
DB_DNODE_ENTER(dbuf);
dn = DB_DNODE(dbuf);
rw_enter(&dn->dn_struct_rwlock, RW_READER);
blkid = dbuf_whichblock(dn, offset);
VERIFY((db = dbuf_hold(dn, blkid, FTAG)) != NULL);
rw_exit(&dn->dn_struct_rwlock);
DB_DNODE_EXIT(dbuf);
if (offset == db->db.db_offset && blksz == db->db.db_size) {
dbuf_assign_arcbuf(db, buf, tx);
dbuf_rele(db, FTAG);
} else {
objset_t *os;
uint64_t object;
DB_DNODE_ENTER(dbuf);
dn = DB_DNODE(dbuf);
os = dn->dn_objset;
object = dn->dn_object;
DB_DNODE_EXIT(dbuf);
dbuf_rele(db, FTAG);
dmu_write(os, object, offset, blksz, buf->b_data, tx);
dmu_return_arcbuf(buf);
XUIOSTAT_BUMP(xuiostat_wbuf_copied);
}
}
typedef struct {
dbuf_dirty_record_t *dsa_dr;
dmu_sync_cb_t *dsa_done;
zgd_t *dsa_zgd;
dmu_tx_t *dsa_tx;
} dmu_sync_arg_t;
/* ARGSUSED */
static void
dmu_sync_ready(zio_t *zio, arc_buf_t *buf, void *varg)
{
dmu_sync_arg_t *dsa = varg;
dmu_buf_t *db = dsa->dsa_zgd->zgd_db;
blkptr_t *bp = zio->io_bp;
if (zio->io_error == 0) {
if (BP_IS_HOLE(bp)) {
/*
* A block of zeros may compress to a hole, but the
* block size still needs to be known for replay.
*/
BP_SET_LSIZE(bp, db->db_size);
} else {
ASSERT(BP_GET_LEVEL(bp) == 0);
bp->blk_fill = 1;
}
}
}
static void
dmu_sync_late_arrival_ready(zio_t *zio)
{
dmu_sync_ready(zio, NULL, zio->io_private);
}
/* ARGSUSED */
static void
dmu_sync_done(zio_t *zio, arc_buf_t *buf, void *varg)
{
dmu_sync_arg_t *dsa = varg;
dbuf_dirty_record_t *dr = dsa->dsa_dr;
dmu_buf_impl_t *db = dr->dr_dbuf;
mutex_enter(&db->db_mtx);
ASSERT(dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC);
if (zio->io_error == 0) {
dr->dt.dl.dr_overridden_by = *zio->io_bp;
dr->dt.dl.dr_override_state = DR_OVERRIDDEN;
dr->dt.dl.dr_copies = zio->io_prop.zp_copies;
if (BP_IS_HOLE(&dr->dt.dl.dr_overridden_by))
BP_ZERO(&dr->dt.dl.dr_overridden_by);
} else {
dr->dt.dl.dr_override_state = DR_NOT_OVERRIDDEN;
}
cv_broadcast(&db->db_changed);
mutex_exit(&db->db_mtx);
dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
kmem_free(dsa, sizeof (*dsa));
}
static void
dmu_sync_late_arrival_done(zio_t *zio)
{
blkptr_t *bp = zio->io_bp;
dmu_sync_arg_t *dsa = zio->io_private;
if (zio->io_error == 0 && !BP_IS_HOLE(bp)) {
ASSERT(zio->io_bp->blk_birth == zio->io_txg);
ASSERT(zio->io_txg > spa_syncing_txg(zio->io_spa));
zio_free(zio->io_spa, zio->io_txg, zio->io_bp);
}
dmu_tx_commit(dsa->dsa_tx);
dsa->dsa_done(dsa->dsa_zgd, zio->io_error);
kmem_free(dsa, sizeof (*dsa));
}
static int
dmu_sync_late_arrival(zio_t *pio, objset_t *os, dmu_sync_cb_t *done, zgd_t *zgd,
zio_prop_t *zp, zbookmark_t *zb)
{
dmu_sync_arg_t *dsa;
dmu_tx_t *tx;
tx = dmu_tx_create(os);
dmu_tx_hold_space(tx, zgd->zgd_db->db_size);
if (dmu_tx_assign(tx, TXG_WAIT) != 0) {
dmu_tx_abort(tx);
return (EIO); /* Make zl_get_data do txg_waited_synced() */
}
dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
dsa->dsa_dr = NULL;
dsa->dsa_done = done;
dsa->dsa_zgd = zgd;
dsa->dsa_tx = tx;
zio_nowait(zio_write(pio, os->os_spa, dmu_tx_get_txg(tx), zgd->zgd_bp,
zgd->zgd_db->db_data, zgd->zgd_db->db_size, zp,
dmu_sync_late_arrival_ready, dmu_sync_late_arrival_done, dsa,
ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, zb));
return (0);
}
/*
* Intent log support: sync the block associated with db to disk.
* N.B. and XXX: the caller is responsible for making sure that the
* data isn't changing while dmu_sync() is writing it.
*
* Return values:
*
* EEXIST: this txg has already been synced, so there's nothing to to.
* The caller should not log the write.
*
* ENOENT: the block was dbuf_free_range()'d, so there's nothing to do.
* The caller should not log the write.
*
* EALREADY: this block is already in the process of being synced.
* The caller should track its progress (somehow).
*
* EIO: could not do the I/O.
* The caller should do a txg_wait_synced().
*
* 0: the I/O has been initiated.
* The caller should log this blkptr in the done callback.
* It is possible that the I/O will fail, in which case
* the error will be reported to the done callback and
* propagated to pio from zio_done().
*/
int
dmu_sync(zio_t *pio, uint64_t txg, dmu_sync_cb_t *done, zgd_t *zgd)
{
blkptr_t *bp = zgd->zgd_bp;
dmu_buf_impl_t *db = (dmu_buf_impl_t *)zgd->zgd_db;
objset_t *os = db->db_objset;
dsl_dataset_t *ds = os->os_dsl_dataset;
dbuf_dirty_record_t *dr;
dmu_sync_arg_t *dsa;
zbookmark_t zb;
zio_prop_t zp;
dnode_t *dn;
ASSERT(pio != NULL);
ASSERT(BP_IS_HOLE(bp));
ASSERT(txg != 0);
SET_BOOKMARK(&zb, ds->ds_object,
db->db.db_object, db->db_level, db->db_blkid);
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
dmu_write_policy(os, dn, db->db_level, WP_DMU_SYNC, &zp);
DB_DNODE_EXIT(db);
/*
* If we're frozen (running ziltest), we always need to generate a bp.
*/
if (txg > spa_freeze_txg(os->os_spa))
return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
/*
* Grabbing db_mtx now provides a barrier between dbuf_sync_leaf()
* and us. If we determine that this txg is not yet syncing,
* but it begins to sync a moment later, that's OK because the
* sync thread will block in dbuf_sync_leaf() until we drop db_mtx.
*/
mutex_enter(&db->db_mtx);
if (txg <= spa_last_synced_txg(os->os_spa)) {
/*
* This txg has already synced. There's nothing to do.
*/
mutex_exit(&db->db_mtx);
return (EEXIST);
}
if (txg <= spa_syncing_txg(os->os_spa)) {
/*
* This txg is currently syncing, so we can't mess with
* the dirty record anymore; just write a new log block.
*/
mutex_exit(&db->db_mtx);
return (dmu_sync_late_arrival(pio, os, done, zgd, &zp, &zb));
}
dr = db->db_last_dirty;
while (dr && dr->dr_txg != txg)
dr = dr->dr_next;
if (dr == NULL) {
/*
* There's no dr for this dbuf, so it must have been freed.
* There's no need to log writes to freed blocks, so we're done.
*/
mutex_exit(&db->db_mtx);
return (ENOENT);
}
ASSERT(dr->dr_txg == txg);
if (dr->dt.dl.dr_override_state == DR_IN_DMU_SYNC ||
dr->dt.dl.dr_override_state == DR_OVERRIDDEN) {
/*
* We have already issued a sync write for this buffer,
* or this buffer has already been synced. It could not
* have been dirtied since, or we would have cleared the state.
*/
mutex_exit(&db->db_mtx);
return (EALREADY);
}
ASSERT(dr->dt.dl.dr_override_state == DR_NOT_OVERRIDDEN);
dr->dt.dl.dr_override_state = DR_IN_DMU_SYNC;
mutex_exit(&db->db_mtx);
dsa = kmem_alloc(sizeof (dmu_sync_arg_t), KM_SLEEP);
dsa->dsa_dr = dr;
dsa->dsa_done = done;
dsa->dsa_zgd = zgd;
dsa->dsa_tx = NULL;
zio_nowait(arc_write(pio, os->os_spa, txg,
bp, dr->dt.dl.dr_data, DBUF_IS_L2CACHEABLE(db), &zp,
dmu_sync_ready, dmu_sync_done, dsa,
ZIO_PRIORITY_SYNC_WRITE, ZIO_FLAG_CANFAIL, &zb));
return (0);
}
int
dmu_object_set_blocksize(objset_t *os, uint64_t object, uint64_t size, int ibs,
dmu_tx_t *tx)
{
dnode_t *dn;
int err;
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
err = dnode_set_blksz(dn, size, ibs, tx);
dnode_rele(dn, FTAG);
return (err);
}
void
dmu_object_set_checksum(objset_t *os, uint64_t object, uint8_t checksum,
dmu_tx_t *tx)
{
dnode_t *dn;
/* XXX assumes dnode_hold will not get an i/o error */
(void) dnode_hold(os, object, FTAG, &dn);
ASSERT(checksum < ZIO_CHECKSUM_FUNCTIONS);
dn->dn_checksum = checksum;
dnode_setdirty(dn, tx);
dnode_rele(dn, FTAG);
}
void
dmu_object_set_compress(objset_t *os, uint64_t object, uint8_t compress,
dmu_tx_t *tx)
{
dnode_t *dn;
/* XXX assumes dnode_hold will not get an i/o error */
(void) dnode_hold(os, object, FTAG, &dn);
ASSERT(compress < ZIO_COMPRESS_FUNCTIONS);
dn->dn_compress = compress;
dnode_setdirty(dn, tx);
dnode_rele(dn, FTAG);
}
int zfs_mdcomp_disable = 0;
void
dmu_write_policy(objset_t *os, dnode_t *dn, int level, int wp, zio_prop_t *zp)
{
dmu_object_type_t type = dn ? dn->dn_type : DMU_OT_OBJSET;
boolean_t ismd = (level > 0 || dmu_ot[type].ot_metadata ||
(wp & WP_SPILL));
enum zio_checksum checksum = os->os_checksum;
enum zio_compress compress = os->os_compress;
enum zio_checksum dedup_checksum = os->os_dedup_checksum;
boolean_t dedup;
boolean_t dedup_verify = os->os_dedup_verify;
int copies = os->os_copies;
/*
* Determine checksum setting.
*/
if (ismd) {
/*
* Metadata always gets checksummed. If the data
* checksum is multi-bit correctable, and it's not a
* ZBT-style checksum, then it's suitable for metadata
* as well. Otherwise, the metadata checksum defaults
* to fletcher4.
*/
if (zio_checksum_table[checksum].ci_correctable < 1 ||
zio_checksum_table[checksum].ci_eck)
checksum = ZIO_CHECKSUM_FLETCHER_4;
} else {
checksum = zio_checksum_select(dn->dn_checksum, checksum);
}
/*
* Determine compression setting.
*/
if (ismd) {
/*
* XXX -- we should design a compression algorithm
* that specializes in arrays of bps.
*/
compress = zfs_mdcomp_disable ? ZIO_COMPRESS_EMPTY :
ZIO_COMPRESS_LZJB;
} else {
compress = zio_compress_select(dn->dn_compress, compress);
}
/*
* Determine dedup setting. If we are in dmu_sync(), we won't
* actually dedup now because that's all done in syncing context;
* but we do want to use the dedup checkum. If the checksum is not
* strong enough to ensure unique signatures, force dedup_verify.
*/
dedup = (!ismd && dedup_checksum != ZIO_CHECKSUM_OFF);
if (dedup) {
checksum = dedup_checksum;
if (!zio_checksum_table[checksum].ci_dedup)
dedup_verify = 1;
}
if (wp & WP_DMU_SYNC)
dedup = 0;
if (wp & WP_NOFILL) {
ASSERT(!ismd && level == 0);
checksum = ZIO_CHECKSUM_OFF;
compress = ZIO_COMPRESS_OFF;
dedup = B_FALSE;
}
zp->zp_checksum = checksum;
zp->zp_compress = compress;
zp->zp_type = (wp & WP_SPILL) ? dn->dn_bonustype : type;
zp->zp_level = level;
zp->zp_copies = MIN(copies + ismd, spa_max_replication(os->os_spa));
zp->zp_dedup = dedup;
zp->zp_dedup_verify = dedup && dedup_verify;
}
int
dmu_offset_next(objset_t *os, uint64_t object, boolean_t hole, uint64_t *off)
{
dnode_t *dn;
int i, err;
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
/*
* Sync any current changes before
* we go trundling through the block pointers.
*/
for (i = 0; i < TXG_SIZE; i++) {
if (list_link_active(&dn->dn_dirty_link[i]))
break;
}
if (i != TXG_SIZE) {
dnode_rele(dn, FTAG);
txg_wait_synced(dmu_objset_pool(os), 0);
err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
}
err = dnode_next_offset(dn, (hole ? DNODE_FIND_HOLE : 0), off, 1, 1, 0);
dnode_rele(dn, FTAG);
return (err);
}
void
dmu_object_info_from_dnode(dnode_t *dn, dmu_object_info_t *doi)
{
dnode_phys_t *dnp;
int i;
rw_enter(&dn->dn_struct_rwlock, RW_READER);
mutex_enter(&dn->dn_mtx);
dnp = dn->dn_phys;
doi->doi_data_block_size = dn->dn_datablksz;
doi->doi_metadata_block_size = dn->dn_indblkshift ?
1ULL << dn->dn_indblkshift : 0;
doi->doi_type = dn->dn_type;
doi->doi_bonus_type = dn->dn_bonustype;
doi->doi_bonus_size = dn->dn_bonuslen;
doi->doi_indirection = dn->dn_nlevels;
doi->doi_checksum = dn->dn_checksum;
doi->doi_compress = dn->dn_compress;
doi->doi_physical_blocks_512 = (DN_USED_BYTES(dnp) + 256) >> 9;
doi->doi_max_offset = (dnp->dn_maxblkid + 1) * dn->dn_datablksz;
doi->doi_fill_count = 0;
for (i = 0; i < dnp->dn_nblkptr; i++)
doi->doi_fill_count += dnp->dn_blkptr[i].blk_fill;
mutex_exit(&dn->dn_mtx);
rw_exit(&dn->dn_struct_rwlock);
}
/*
* Get information on a DMU object.
* If doi is NULL, just indicates whether the object exists.
*/
int
dmu_object_info(objset_t *os, uint64_t object, dmu_object_info_t *doi)
{
dnode_t *dn;
int err = dnode_hold(os, object, FTAG, &dn);
if (err)
return (err);
if (doi != NULL)
dmu_object_info_from_dnode(dn, doi);
dnode_rele(dn, FTAG);
return (0);
}
/*
* As above, but faster; can be used when you have a held dbuf in hand.
*/
void
dmu_object_info_from_db(dmu_buf_t *db_fake, dmu_object_info_t *doi)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
DB_DNODE_ENTER(db);
dmu_object_info_from_dnode(DB_DNODE(db), doi);
DB_DNODE_EXIT(db);
}
/*
* Faster still when you only care about the size.
* This is specifically optimized for zfs_getattr().
*/
void
dmu_object_size_from_db(dmu_buf_t *db_fake, uint32_t *blksize,
u_longlong_t *nblk512)
{
dmu_buf_impl_t *db = (dmu_buf_impl_t *)db_fake;
dnode_t *dn;
DB_DNODE_ENTER(db);
dn = DB_DNODE(db);
*blksize = dn->dn_datablksz;
/* add 1 for dnode space */
*nblk512 = ((DN_USED_BYTES(dn->dn_phys) + SPA_MINBLOCKSIZE/2) >>
SPA_MINBLOCKSHIFT) + 1;
DB_DNODE_EXIT(db);
}
void
byteswap_uint64_array(void *vbuf, size_t size)
{
uint64_t *buf = vbuf;
size_t count = size >> 3;
int i;
ASSERT((size & 7) == 0);
for (i = 0; i < count; i++)
buf[i] = BSWAP_64(buf[i]);
}
void
byteswap_uint32_array(void *vbuf, size_t size)
{
uint32_t *buf = vbuf;
size_t count = size >> 2;
int i;
ASSERT((size & 3) == 0);
for (i = 0; i < count; i++)
buf[i] = BSWAP_32(buf[i]);
}
void
byteswap_uint16_array(void *vbuf, size_t size)
{
uint16_t *buf = vbuf;
size_t count = size >> 1;
int i;
ASSERT((size & 1) == 0);
for (i = 0; i < count; i++)
buf[i] = BSWAP_16(buf[i]);
}
/* ARGSUSED */
void
byteswap_uint8_array(void *vbuf, size_t size)
{
}
void
dmu_init(void)
{
zfs_dbgmsg_init();
sa_cache_init();
xuio_stat_init();
dmu_objset_init();
dnode_init();
dbuf_init();
zfetch_init();
arc_init();
l2arc_init();
}
void
dmu_fini(void)
{
l2arc_fini();
arc_fini();
zfetch_fini();
dbuf_fini();
dnode_fini();
dmu_objset_fini();
xuio_stat_fini();
sa_cache_fini();
zfs_dbgmsg_fini();
}
#if defined(_KERNEL) && defined(HAVE_SPL)
EXPORT_SYMBOL(dmu_bonus_hold);
EXPORT_SYMBOL(dmu_free_range);
EXPORT_SYMBOL(dmu_read);
EXPORT_SYMBOL(dmu_write);
/* Get information on a DMU object. */
EXPORT_SYMBOL(dmu_object_info);
EXPORT_SYMBOL(dmu_object_info_from_dnode);
EXPORT_SYMBOL(dmu_object_info_from_db);
EXPORT_SYMBOL(dmu_object_size_from_db);
EXPORT_SYMBOL(dmu_object_set_blocksize);
EXPORT_SYMBOL(dmu_object_set_checksum);
EXPORT_SYMBOL(dmu_object_set_compress);
EXPORT_SYMBOL(dmu_ot);
#endif