nl-cache: In case of nameless operations do not cache

Issue:
In nameless lookup/other fops, parent inode will be NULL, when we try
to add the cache to the NULL inode, it causes a crash.

Hence handle the scenario of nameless fops, and do not cache/serve
the nameless fops.

>Reviewed-on: https://review.gluster.org/17316
>Smoke: Gluster Build System <jenkins@build.gluster.org>
>NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
>Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
>CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
>(cherry picked from commit 284cd8851bfe60984d2f11b5c52fe3204ff43b06)

Change-Id: I3b90f882ac89e6aaf3419db89e6f890797f37700
BUG: 1454569
Signed-off-by: Poornima G <pgurusid@redhat.com>
Reviewed-on: https://review.gluster.org/17361
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Shyamsundar Ranganathan <srangana@redhat.com>

4 files changed, 48 insertions, 4 deletions

diff --git a/libglusterfs/src/xlator.c b/libglusterfs/src/xlator.c
index ec7cbe08ad3..9da6d657707 100644
--- a/libglusterfs/src/xlator.c
+++ b/libglusterfs/src/xlator.c
@@ -1028,6 +1028,21 @@ out:
         return ret;
 }
 
+
+gf_boolean_t
+loc_is_nameless (loc_t *loc)
+{
+        gf_boolean_t ret = _gf_false;
+
+        GF_VALIDATE_OR_GOTO ("xlator", loc, out);
+
+        if ((!loc->parent && gf_uuid_is_null (loc->pargfid)) || !loc->name)
+                ret = _gf_true;
+out:
+        return ret;
+}
+
+
 int
 xlator_destroy (xlator_t *xl)
 {
diff --git a/libglusterfs/src/xlator.h b/libglusterfs/src/xlator.h
index e0f82a70764..894785e7985 100644
--- a/libglusterfs/src/xlator.h
+++ b/libglusterfs/src/xlator.h
@@ -1030,6 +1030,7 @@ void loc_pargfid (loc_t *loc, uuid_t pargfid);
 char* loc_gfid_utoa (loc_t *loc);
 gf_boolean_t loc_is_root (loc_t *loc);
 int32_t loc_build_child (loc_t *child, loc_t *parent, char *name);
+gf_boolean_t loc_is_nameless (loc_t *loc);
 int xlator_mem_acct_init (xlator_t *xl, int num_types);
 int is_gf_log_command (xlator_t *trans, const char *name, char *value);
 int glusterd_check_log_level (const char *value);
diff --git a/tests/bugs/nl-cache/bug-1451588.t b/tests/bugs/nl-cache/bug-1451588.t
new file mode 100755
index 00000000000..cf07d04c5cc
--- /dev/null
+++ b/tests/bugs/nl-cache/bug-1451588.t
@@ -0,0 +1,25 @@
+#!/bin/bash
+
+. $(dirname $0)/../../include.rc
+. $(dirname $0)/../../volume.rc
+
+cleanup;
+
+TEST glusterd
+
+TEST $CLI volume create $V0 $H0:$B0/${V0}{0..4}
+EXPECT 'Created' volinfo_field $V0 'Status'
+
+TEST $CLI volume set $V0 performance.nl-cache on
+TEST $CLI volume set $V0 features.cache-invalidation on
+TEST $CLI volume set $V0 features.cache-invalidation-timeout 600
+
+TEST $CLI volume start $V0;
+EXPECT 'Started' volinfo_field $V0 'Status';
+
+TEST glusterfs --volfile-id=/$V0 --aux-gfid-mount --volfile-server=$H0 $M0
+
+TEST ! stat $M0/.gfid/1901b1a0-c612-46ee-b45a-e8345d5a0b48
+
+cleanup;
+G_TESTDEF_TEST_STATUS_NETBSD7=BAD_TEST,BUG=000000
diff --git a/xlators/performance/nl-cache/src/nl-cache.c b/xlators/performance/nl-cache/src/nl-cache.c
index 675b5de24bf..295d5f67515 100644
--- a/xlators/performance/nl-cache/src/nl-cache.c
+++ b/xlators/performance/nl-cache/src/nl-cache.c
@@ -198,6 +198,8 @@ nlc_lookup_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
         local = frame->local;
         conf = this->private;
 
+        GF_VALIDATE_OR_GOTO (this->name, local, out);
+
         /* Donot add to pe, this may lead to duplicate entry and
          * requires search before adding if list of strings */
         if (op_ret < 0 && op_errno == ENOENT) {
@@ -205,8 +207,9 @@ nlc_lookup_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                 GF_ATOMIC_INC (conf->nlc_counter.nlc_miss);
         }
 
+out:
         NLC_STACK_UNWIND (lookup, frame, op_ret, op_errno, inode, buf, xdata,
-                         postparent);
+                          postparent);
         return 0;
 }
 
@@ -218,15 +221,15 @@ nlc_lookup (call_frame_t *frame, xlator_t *this, loc_t *loc, dict_t *xdata)
         nlc_conf_t  *conf  = NULL;
         inode_t     *inode = NULL;
 
+        if (loc_is_nameless (loc))
+                goto wind;
+
         local = nlc_local_init (frame, this, GF_FOP_LOOKUP, loc, NULL);
         if (!local)
                 goto err;
 
         conf = this->private;
 
-        if ((!loc->parent && gf_uuid_is_null (loc->pargfid)) || !loc->name)
-                goto wind;
-
         inode = inode_grep (loc->inode->table, loc->parent, loc->name);
         if (inode) {
                 inode_unref (inode);