mount/fuse: perform lookup() on inodes linked through readdirplus

Some xlators still require lookup() fop to be sent for proper working.
This patch remembers inodes which have been linked through readdiprlus
and makes the resolver send lookups on them.

Also, introduce and use context count for inode table.

Change-Id: Ibe8a04a659539d90dfc794521b51bf2bda017a0b
BUG: 979910
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-on: http://review.gluster.org/5267
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-on: http://review.gluster.org/5806

3 files changed, 66 insertions, 8 deletions

diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c
index 8c4edb1e8f3..00f2a625ae1 100644
--- a/xlators/mount/fuse/src/fuse-bridge.c
+++ b/xlators/mount/fuse/src/fuse-bridge.c
@@ -51,6 +51,39 @@ fuse_invalidate(xlator_t *this, inode_t *inode)
         return 0;
 }
 
+void
+fuse_inode_set_need_lookup (inode_t *inode, xlator_t *this)
+{
+	uint64_t          need_lookup = 1;
+
+	if (!inode || !this)
+		return;
+
+	inode_ctx_set (inode, this, &need_lookup);
+
+	return;
+}
+
+
+gf_boolean_t
+fuse_inode_needs_lookup (inode_t *inode, xlator_t *this)
+{
+	uint64_t          need_lookup = 0;
+	gf_boolean_t      ret = _gf_false;
+
+	if (!inode || !this)
+		return ret;
+
+	inode_ctx_get (inode, this, &need_lookup);
+	if (need_lookup)
+		ret = _gf_true;
+	need_lookup = 0;
+	inode_ctx_set (inode, this, &need_lookup);
+
+	return ret;
+}
+
+
 fuse_fd_ctx_t *
 __fuse_fd_ctx_check_n_create (xlator_t *this, fd_t *fd)
 {
@@ -2600,6 +2633,8 @@ fuse_readdirp_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
 
 		feo->nodeid = inode_to_fuse_nodeid (linked_inode);
 
+		fuse_inode_set_need_lookup (linked_inode, this);
+
 		inode_unref (linked_inode);
 
 		feo->entry_valid =
@@ -5314,7 +5349,7 @@ struct volume_options options[] = {
         },
         { .key = {"use-readdirp"},
           .type = GF_OPTION_TYPE_BOOL,
-          .default_value = "no"
+          .default_value = "yes"
         },
         { .key = {NULL} },
 };
diff --git a/xlators/mount/fuse/src/fuse-resolve.c b/xlators/mount/fuse/src/fuse-resolve.c
index 88ce32ab9cd..8565ce0e478 100644
--- a/xlators/mount/fuse/src/fuse-resolve.c
+++ b/xlators/mount/fuse/src/fuse-resolve.c
@@ -26,6 +26,8 @@ int fuse_migrate_fd (xlator_t *this, fd_t *fd, xlator_t *old_subvol,
 fuse_fd_ctx_t *
 fuse_fd_ctx_get (xlator_t *this, fd_t *fd);
 
+gf_boolean_t fuse_inode_needs_lookup (inode_t *inode, xlator_t *this);
+
 static int
 fuse_resolve_loc_touchup (fuse_state_t *state)
 {
@@ -201,7 +203,11 @@ fuse_resolve_gfid (fuse_state_t *state)
                 uuid_copy (resolve_loc->gfid, resolve->gfid);
         }
 
-	resolve_loc->inode = inode_new (state->itable);
+	/* inode may already exist in case we are looking up an inode which was
+	   linked through readdirplus */
+	resolve_loc->inode = inode_find (state->itable, resolve_loc->gfid);
+	if (!resolve_loc->inode)
+		resolve_loc->inode = inode_new (state->itable);
 	ret = loc_path (resolve_loc, NULL);
 
         if (ret <= 0) {
@@ -239,6 +245,9 @@ fuse_resolve_parent_simple (fuse_state_t *state)
 
 	parent = resolve->parhint;
 	if (parent->table == state->itable) {
+		if (fuse_inode_needs_lookup (parent, THIS))
+			return 1;
+
 		/* no graph switches since */
 		loc->parent = inode_ref (parent);
 		uuid_copy (loc->pargfid, parent->gfid);
@@ -265,6 +274,10 @@ fuse_resolve_parent_simple (fuse_state_t *state)
 		/* non decisive result - parent missing */
 		return 1;
 	}
+	if (fuse_inode_needs_lookup (parent, THIS)) {
+		inode_unref (parent);
+		return 1;
+	}
 
 	loc->parent = parent;
         uuid_copy (loc->pargfid, resolve->pargfid);
@@ -314,15 +327,18 @@ fuse_resolve_inode_simple (fuse_state_t *state)
 	loc = state->loc_now;
 
 	inode = resolve->hint;
-	if (inode->table == state->itable) {
+	if (inode->table == state->itable)
 		inode_ref (inode);
-		goto found;
+	else
+		inode = inode_find (state->itable, resolve->gfid);
+
+        if (inode) {
+		if (!fuse_inode_needs_lookup (inode, THIS))
+			goto found;
+		/* inode was linked through readdirplus */
+		inode_unref (inode);
 	}
 
-        inode = inode_find (state->itable, resolve->gfid);
-        if (inode)
-		goto found;
-
         return 1;
 found:
 	loc->inode = inode;
diff --git a/xlators/performance/md-cache/src/md-cache.c b/xlators/performance/md-cache/src/md-cache.c
index b7f1f1d13fe..9292dae76c2 100644
--- a/xlators/performance/md-cache/src/md-cache.c
+++ b/xlators/performance/md-cache/src/md-cache.c
@@ -799,6 +799,13 @@ mdc_lookup (call_frame_t *frame, xlator_t *this, loc_t *loc,
         if (!local)
                 goto uncached;
 
+	if (!loc->name)
+		/* A nameless discovery is dangerous to cache. We
+		   perform nameless lookup with the intention of
+		   re-establishing an inode "properly"
+		*/
+		goto uncached;
+
         loc_copy (&local->loc, loc);
 
         ret = mdc_inode_iatt_get (this, loc->inode, &stbuf);