From 8b2ef5076284e44a87698393c8094c925fa863fa Mon Sep 17 00:00:00 2001 From: Susant Palai Date: Wed, 11 Jan 2017 16:04:47 +0530 Subject: dht: send lookup on old name inside rename with bname and pargfid Inside rename, a lookup is done on the source name to make sure that the file is there. But we used to do a gfid based lookup and hence, even if the source name was renamed to a new name from some other client, lookup will be successful as server3_3_lookup will fetch the new path based on the gfid. So even if the source file does not exist any more rename will carry on, and as server3_3_link(destination is hashed to a different brick other than source cached scenario) also does gfid based resolve, it wont detect that the source name does not exist and hardlink creation will be successful (since gfid based resolve will get the new dentry). To solve this problem, do a name based lookup inside rename. So that rename will fail right away if the source does not exist. Change-Id: Ieba8bdd6675088dbf18de90ed4622df043d163bd BUG: 1412135 Signed-off-by: Susant Palai Reviewed-on: https://review.gluster.org/16375 Smoke: Gluster Build System NetBSD-regression: NetBSD Build System Reviewed-by: N Balachandran CentOS-regression: Gluster Build System Reviewed-by: Raghavendra G --- xlators/cluster/dht/src/dht-rename.c | 67 +++++++++++++++++++++++++++++++----- 1 file changed, 58 insertions(+), 9 deletions(-) (limited to 'xlators/cluster/dht/src') diff --git a/xlators/cluster/dht/src/dht-rename.c b/xlators/cluster/dht/src/dht-rename.c index c24e6ea7aca..32806e911bb 100644 --- a/xlators/cluster/dht/src/dht-rename.c +++ b/xlators/cluster/dht/src/dht-rename.c @@ -1435,9 +1435,15 @@ dht_rename_lookup_cbk (call_frame_t *frame, void *cookie, xlator_t *this, inode_t *inode, struct iatt *stbuf, dict_t *xattr, struct iatt *postparent) { - dht_local_t *local = NULL; - int call_cnt = 0; - dht_conf_t *conf = NULL; + dht_local_t *local = NULL; + int call_cnt = 0; + dht_conf_t *conf = NULL; + char gfid_local[GF_UUID_BUF_SIZE] = {0}; + char gfid_server[GF_UUID_BUF_SIZE] = {0}; + int child_index = -1; + + + child_index = (long)cookie; local = frame->local; conf = this->private; @@ -1456,16 +1462,40 @@ dht_rename_lookup_cbk (call_frame_t *frame, void *cookie, xlator_t *this, * that this is a linkfile and fail the rename operation. */ local->is_linkfile = _gf_true; + local->op_errno = op_errno; } else if (xattr && check_is_linkfile (inode, stbuf, xattr, conf->link_xattr_name)) { local->is_linkfile = _gf_true; + /* Found linkto file instead of data file, passdown ENOENT + * based on the above comment */ + local->op_errno = ENOENT; + } + + if (!local->is_linkfile && + gf_uuid_compare (local->lock[0].layout.parent_layout.locks[child_index]->loc.gfid, + stbuf->ia_gfid)) { + gf_uuid_unparse (local->lock[0].layout.parent_layout.locks[child_index]->loc.gfid, + gfid_local); + gf_uuid_unparse (stbuf->ia_gfid, gfid_server); + + gf_msg (this->name, GF_LOG_WARNING, 0, + DHT_MSG_GFID_MISMATCH, + "path:%s, received a different gfid, local_gfid= %s" + " server_gfid: %s", + local->loc.path, gfid_local, gfid_server); + + /* Will passdown ENOENT anyway since the file we sent on + * rename is replaced with a different file */ + local->op_errno = ENOENT; + /* Since local->is_linkfile is used here to detect failure, + * marking this to true */ + local->is_linkfile = _gf_true; } call_cnt = dht_frame_return (frame); if (is_last_call (call_cnt)) { if (local->is_linkfile) { local->op_ret = -1; - local->op_errno = op_errno; goto fail; } @@ -1529,12 +1559,31 @@ dht_rename_lock_cbk (call_frame_t *frame, void *cookie, xlator_t *this, local->call_cnt = local->lock[0].layout.parent_layout.lk_count; + /* Why not use local->lock.locks[?].loc for lookup post lock phase + * --------------------------------------------------------------- + * "layout.parent_layout.locks[?].loc" does not have the name and pargfid + * populated. + * Reason: If we had populated the name and pargfid, server might + * resolve to a successful lookup even if there is a file with same name + * with a different gfid(unlink & create) as server does name based + * resolution on first priority. And this can result in operating on a + * different inode entirely. + * + * Now consider a scenario where source file was renamed by some other + * client to a new name just before this lock was granted. So if a + * lookup would be done on local->lock[0].layout.parent_layout.locks[?].loc, + * server will send success even if the entry was renamed (since server will + * do a gfid based resolution). So once a lock is granted, make sure the file + * exists with the name that the client requested with. + * */ + for (i = 0; i < local->lock[0].layout.parent_layout.lk_count; i++) { - STACK_WIND (frame, dht_rename_lookup_cbk, - local->lock[0].layout.parent_layout.locks[i]->xl, - local->lock[0].layout.parent_layout.locks[i]->xl->fops->lookup, - &local->lock[0].layout.parent_layout.locks[i]->loc, - xattr_req); + STACK_WIND_COOKIE (frame, dht_rename_lookup_cbk, (void *)(long)i, + local->lock[0].layout.parent_layout.locks[i]->xl, + local->lock[0].layout.parent_layout.locks[i]->xl->fops->lookup, + ((gf_uuid_compare (local->loc.gfid, \ + local->lock[0].layout.parent_layout.locks[i]->loc.gfid) == 0) ? + &local->loc : &local->loc2), xattr_req); } dict_unref (xattr_req); -- cgit