From 4254acb05743dc2175ae76f6e15b0785d4b688fd Mon Sep 17 00:00:00 2001 From: Tim Chase Date: Mon, 10 Nov 2014 23:26:33 -0600 Subject: [PATCH] Undirty freed spill blocks. If a spill block's dbuf hasn't yet been written when a spill block is freed, the unwritten version will still be written. This patch handles the case in which a spill block's dbuf is freed and undirties it to prevent it from being written. The most common case in which this could happen is when xattr=sa is being used and a long xattr is immediately replaced by a short xattr as in: setfattr -n user.test -v very_very_very..._long_value setfattr -n user.test -v short_value The first value must be sufficiently long that a spill block is generated and the second value must be short enough to not require a spill block. In practice, this would typically happen due to internal xattr operations as a result of setting acltype=posixacl. Signed-off-by: Tim Chase Signed-off-by: Brian Behlendorf Closes #2663 Closes #2700 Closes #2701 Closes #2717 Closes #2863 Closes #2884 --- module/zfs/dbuf.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c index 13a0dbfd115f..b2a105efba19 100644 --- a/module/zfs/dbuf.c +++ b/module/zfs/dbuf.c @@ -869,13 +869,16 @@ dbuf_free_range(dnode_t *dn, uint64_t start, uint64_t end, dmu_tx_t *tx) { dmu_buf_impl_t *db, *db_next; uint64_t txg = tx->tx_txg; + boolean_t freespill = + (start == DMU_SPILL_BLKID || end == DMU_SPILL_BLKID); - if (end > dn->dn_maxblkid && (end != DMU_SPILL_BLKID)) + if (end > dn->dn_maxblkid && !freespill) end = dn->dn_maxblkid; dprintf_dnode(dn, "start=%llu end=%llu\n", start, end); mutex_enter(&dn->dn_dbufs_mtx); - if (start >= dn->dn_unlisted_l0_blkid * dn->dn_datablksz) { + if (start >= dn->dn_unlisted_l0_blkid * dn->dn_datablksz && + !freespill) { /* There can't be any dbufs in this range; no need to search. */ mutex_exit(&dn->dn_dbufs_mtx); return; @@ -896,7 +899,7 @@ dbuf_free_range(dnode_t *dn, uint64_t start, uint64_t end, dmu_tx_t *tx) if (db->db_level != 0) continue; - if (db->db_blkid < start || db->db_blkid > end) + if ((db->db_blkid < start || db->db_blkid > end) && !freespill) continue; /* found a level 0 buffer in the range */