diff options
Diffstat (limited to 'module/zfs/zap.c')
| -rw-r--r-- | module/zfs/zap.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/module/zfs/zap.c b/module/zfs/zap.c index d0d438fe3..0ed6d7f49 100644 --- a/module/zfs/zap.c +++ b/module/zfs/zap.c @@ -270,6 +270,7 @@ zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp) uint64_t blk, off; int err; dmu_buf_t *db; + dnode_t *dn; int bs = FZAP_BLOCK_SHIFT(zap); ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); @@ -277,8 +278,15 @@ zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp) blk = idx >> (bs-3); off = idx & ((1<<(bs-3))-1); - err = dmu_buf_hold(zap->zap_objset, zap->zap_object, + /* + * 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. + */ + dn = dmu_buf_dnode_enter(zap->zap_dbuf); + 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) return (err); *valp = ((uint64_t *)db->db_data)[off]; @@ -292,9 +300,11 @@ zap_table_load(zap_t *zap, zap_table_phys_t *tbl, uint64_t idx, uint64_t *valp) */ blk = (idx*2) >> (bs-3); - err = dmu_buf_hold(zap->zap_objset, zap->zap_object, + 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); } @@ -502,6 +512,7 @@ zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt, zap_leaf_t *l; int bs = FZAP_BLOCK_SHIFT(zap); int err; + dnode_t *dn; ASSERT(RW_LOCK_HELD(&zap->zap_rwlock)); @@ -515,8 +526,10 @@ zap_get_leaf_byblk(zap_t *zap, uint64_t blkid, dmu_tx_t *tx, krw_t lt, if (blkid == 0) return (ENOENT); - err = dmu_buf_hold(zap->zap_objset, zap->zap_object, + dn = dmu_buf_dnode_enter(zap->zap_dbuf); + err = dmu_buf_hold_by_dnode(dn, blkid << bs, NULL, &db, DMU_READ_NO_PREFETCH); + dmu_buf_dnode_exit(zap->zap_dbuf); if (err) return (err); |