Archive-Team
/
zfs
2
0
Fork 0
Code Issues Pull Requests Packages Projects Releases 103 Wiki Activity

Add dmu_tx_hold_append() interface 

Provides an interface which callers can use to declare a write when
the exact starting offset in not yet known.  Since the full range
being updated is not available only the first L0 block at the
provided offset will be prefetched.

Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #14819
This commit is contained in:
Brian Behlendorf 2023-05-09 09:03:10 -07:00
parent 7c555fee9d
commit 133faca275
3 changed files with 109 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
include/sys/dmu.h
View File

@ -778,6 +778,9 @@ dmu_tx_t *dmu_tx_create(objset_t *os);
void dmu_tx_hold_write(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
void dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,
int len);
void dmu_tx_hold_append(dmu_tx_t *tx, uint64_t object, uint64_t off, int len);
void dmu_tx_hold_append_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,
int len);
void dmu_tx_hold_free(dmu_tx_t *tx, uint64_t object, uint64_t off,
uint64_t len);
void dmu_tx_hold_free_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off,

1
include/sys/dmu_tx.h
View File

@ -90,6 +90,7 @@ enum dmu_tx_hold_type {
THT_ZAP,
THT_SPACE,
THT_SPILL,
THT_APPEND,
THT_NUMTYPES
};

105
module/zfs/dmu_tx.c
View File

@ -290,6 +290,53 @@ dmu_tx_count_write(dmu_tx_hold_t *txh, uint64_t off, uint64_t len)
}
}
static void
dmu_tx_count_append(dmu_tx_hold_t *txh, uint64_t off, uint64_t len)
{
dnode_t *dn = txh->txh_dnode;
int err = 0;
if (len == 0)
return;
(void) zfs_refcount_add_many(&txh->txh_space_towrite, len, FTAG);
if (dn == NULL)
return;
/*
* For i/o error checking, read the blocks that will be needed
* to perform the append; first level-0 block (if not aligned, i.e.
* if they are partial-block writes), no additional blocks are read.
*/
if (dn->dn_maxblkid == 0) {
if (off < dn->dn_datablksz &&
(off > 0 || len < dn->dn_datablksz)) {
err = dmu_tx_check_ioerr(NULL, dn, 0, 0);
if (err != 0) {
txh->txh_tx->tx_err = err;
}
}
} else {
zio_t *zio = zio_root(dn->dn_objset->os_spa,
NULL, NULL, ZIO_FLAG_CANFAIL);
/* first level-0 block */
uint64_t start = off >> dn->dn_datablkshift;
if (P2PHASE(off, dn->dn_datablksz) || len < dn->dn_datablksz) {
err = dmu_tx_check_ioerr(zio, dn, 0, start);
if (err != 0) {
txh->txh_tx->tx_err = err;
}
}
err = zio_wait(zio);
if (err != 0) {
txh->txh_tx->tx_err = err;
}
}
}
static void
dmu_tx_count_dnode(dmu_tx_hold_t *txh)
{
@ -330,6 +377,42 @@ dmu_tx_hold_write_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, int len)
}
}
/*
* Should be used when appending to an object and the exact offset is unknown.
* The write must occur at or beyond the specified offset. Only the L0 block
* at provided offset will be prefetched.
*/
void
dmu_tx_hold_append(dmu_tx_t *tx, uint64_t object, uint64_t off, int len)
{
dmu_tx_hold_t *txh;
ASSERT0(tx->tx_txg);
ASSERT3U(len, <=, DMU_MAX_ACCESS);
txh = dmu_tx_hold_object_impl(tx, tx->tx_objset,
object, THT_APPEND, off, DMU_OBJECT_END);
if (txh != NULL) {
dmu_tx_count_append(txh, off, len);
dmu_tx_count_dnode(txh);
}
}
void
dmu_tx_hold_append_by_dnode(dmu_tx_t *tx, dnode_t *dn, uint64_t off, int len)
{
dmu_tx_hold_t *txh;
ASSERT0(tx->tx_txg);
ASSERT3U(len, <=, DMU_MAX_ACCESS);
txh = dmu_tx_hold_dnode_impl(tx, dn, THT_APPEND, off, DMU_OBJECT_END);
if (txh != NULL) {
dmu_tx_count_append(txh, off, len);
dmu_tx_count_dnode(txh);
}
}
/*
* This function marks the transaction as being a "net free". The end
* result is that refquotas will be disabled for this transaction, and
@ -638,6 +721,26 @@ dmu_tx_dirty_buf(dmu_tx_t *tx, dmu_buf_impl_t *db)
if (blkid == 0)
match_offset = TRUE;
break;
case THT_APPEND:
if (blkid >= beginblk && (blkid <= endblk ||
txh->txh_arg2 == DMU_OBJECT_END))
match_offset = TRUE;
/*
* THT_WRITE used for bonus and spill blocks.
*/
ASSERT(blkid != DMU_BONUS_BLKID &&
blkid != DMU_SPILL_BLKID);
/*
* They might have to increase nlevels,
* thus dirtying the new TLIBs. Or the
* might have to change the block size,
* thus dirying the new lvl=0 blk=0.
*/
if (blkid == 0)
match_offset = TRUE;
break;
case THT_FREE:
/*
* We will dirty all the level 1 blocks in
@ -1421,6 +1524,8 @@ dmu_tx_fini(void)
EXPORT_SYMBOL(dmu_tx_create);
EXPORT_SYMBOL(dmu_tx_hold_write);
EXPORT_SYMBOL(dmu_tx_hold_write_by_dnode);
EXPORT_SYMBOL(dmu_tx_hold_append);
EXPORT_SYMBOL(dmu_tx_hold_append_by_dnode);
EXPORT_SYMBOL(dmu_tx_hold_free);
EXPORT_SYMBOL(dmu_tx_hold_free_by_dnode);
EXPORT_SYMBOL(dmu_tx_hold_zap);