Handle zap_add() failures in mixed case mode

With "casesensitivity=mixed", zap_add() could fail when the number of
files/directories with the same name (varying in case) exceed the
capacity of the leaf node of a Fatzap. This results in a ASSERT()
failure as zfs_link_create() does not expect zap_add() to fail. The fix
is to handle these failures and rollback the transactions.

Reviewed by: Matt Ahrens <mahrens@delphix.com>
Reviewed-by: Chunwei Chen <david.chen@nutanix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Sanjeev Bagewadi <sanjeev.bagewadi@gmail.com>
Closes #7011 
Closes #7054
This commit is contained in:
sanjeevbagewadi
2018-02-09 23:45:53 +05:30
committed by Brian Behlendorf
parent eb9c4532dd
commit cc63068e95
9 changed files with 290 additions and 32 deletions
+37 -1
View File
@@ -363,6 +363,41 @@ mze_find_unused_cd(zap_t *zap, uint64_t hash)
return (cd);
}
/*
* Each mzap entry requires at max : 4 chunks
* 3 chunks for names + 1 chunk for value.
*/
#define MZAP_ENT_CHUNKS (1 + ZAP_LEAF_ARRAY_NCHUNKS(MZAP_NAME_LEN) + \
ZAP_LEAF_ARRAY_NCHUNKS(sizeof (uint64_t)))
/*
* Check if the current entry keeps the colliding entries under the fatzap leaf
* size.
*/
static boolean_t
mze_canfit_fzap_leaf(zap_name_t *zn, uint64_t hash)
{
zap_t *zap = zn->zn_zap;
mzap_ent_t mze_tofind;
mzap_ent_t *mze;
avl_index_t idx;
avl_tree_t *avl = &zap->zap_m.zap_avl;
uint32_t mzap_ents = 0;
mze_tofind.mze_hash = hash;
mze_tofind.mze_cd = 0;
for (mze = avl_find(avl, &mze_tofind, &idx);
mze && mze->mze_hash == hash; mze = AVL_NEXT(avl, mze)) {
mzap_ents++;
}
/* Include the new entry being added */
mzap_ents++;
return (ZAP_LEAF_NUMCHUNKS_DEF > (mzap_ents * MZAP_ENT_CHUNKS));
}
static void
mze_remove(zap_t *zap, mzap_ent_t *mze)
{
@@ -1190,7 +1225,8 @@ zap_add_impl(zap_t *zap, const char *key,
err = fzap_add(zn, integer_size, num_integers, val, tag, tx);
zap = zn->zn_zap; /* fzap_add() may change zap */
} else if (integer_size != 8 || num_integers != 1 ||
strlen(key) >= MZAP_NAME_LEN) {
strlen(key) >= MZAP_NAME_LEN ||
!mze_canfit_fzap_leaf(zn, zn->zn_hash)) {
err = mzap_upgrade(&zn->zn_zap, tag, tx, 0);
if (err == 0) {
err = fzap_add(zn, integer_size, num_integers, val,