afr: heal metadata in discover code path

Combined backport of https://review.gluster.org/17850 and
https://review.gluster.org/18187

During graph switch, if fuse sends nameless (gfid) lookups, afr takes
the discover code path to serve it. If there are pending metadata heals,
they do not happen unless an inode refresh happens as a part of
discover (which is not guaranteed to happen always).

This patch fixes it by attempting metadata heal as a part of discover,
just like how it is done in lookup code path.

Change-Id: I87c493045b9225741cad173bf3f645848697032e
BUG: 1488168
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-on: https://review.gluster.org/18202
Smoke: Gluster Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Karthik U S <ksubrahm@redhat.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Reviewed-by: jiffin tony Thottan <jthottan@redhat.com>

2 files changed, 46 insertions, 17 deletions

diff --git a/xlators/cluster/afr/src/afr-common.c b/xlators/cluster/afr/src/afr-common.c
index f43668cbbe5..46d4d012f59 100644
--- a/xlators/cluster/afr/src/afr-common.c
+++ b/xlators/cluster/afr/src/afr-common.c
@@ -60,6 +60,9 @@ int
 afr_fav_child_reset_sink_xattrs_cbk (int ret, call_frame_t *frame,
                                      void *opaque);
 
+static void
+afr_discover_done (call_frame_t *frame, xlator_t *this);
+
 gf_boolean_t
 afr_is_consistent_io_possible (afr_local_t *local, afr_private_t *priv,
                                int32_t *op_errno)
@@ -1037,7 +1040,7 @@ int
 afr_refresh_selfheal_done (int ret, call_frame_t *heal, void *opaque)
 {
 	if (heal)
-		STACK_DESTROY (heal->root);
+                AFR_STACK_DESTROY (heal);
 	return 0;
 }
 
@@ -2436,13 +2439,25 @@ afr_lookup_sh_metadata_wrap (void *opaque)
                               "Unable to set link-count in dict ");
         }
 
-        inode = afr_selfheal_unlocked_lookup_on (frame, local->loc.parent,
-                                                 local->loc.name, local->replies,
-                                                 local->child_up, dict);
+        if (loc_is_nameless (&local->loc)) {
+                ret = afr_selfheal_unlocked_discover_on (frame, local->inode,
+                                                         local->loc.gfid,
+                                                         local->replies,
+                                                         local->child_up);
+        } else {
+                inode = afr_selfheal_unlocked_lookup_on (frame,
+                                                         local->loc.parent,
+                                                         local->loc.name,
+                                                         local->replies,
+                                                         local->child_up, dict);
+        }
         if (inode)
                 inode_unref (inode);
 out:
-        afr_lookup_done (frame, this);
+        if (loc_is_nameless (&local->loc))
+                afr_discover_done (frame, this);
+        else
+                afr_lookup_done (frame, this);
 
         if (dict)
                 dict_unref (dict);
@@ -2507,21 +2522,29 @@ afr_lookup_metadata_heal_check (call_frame_t *frame, xlator_t *this)
 
 {
         call_frame_t *heal = NULL;
+        afr_local_t *local = NULL;
         int ret            = 0;
 
+        local = frame->local;
         if (!afr_can_start_metadata_self_heal (frame, this))
                 goto out;
 
-        heal = copy_frame (frame);
-        if (heal)
-                heal->root->pid = GF_CLIENT_PID_SELF_HEALD;
+        heal = afr_frame_create (this);
+        if (!heal)
+                goto out;
+
         ret = synctask_new (this->ctx->env, afr_lookup_sh_metadata_wrap,
                             afr_refresh_selfheal_done, heal, frame);
-        if(ret)
+        if (ret)
                 goto out;
         return ret;
 out:
-        afr_lookup_done (frame, this);
+        if (loc_is_nameless (&local->loc))
+                afr_discover_done (frame, this);
+        else
+                afr_lookup_done (frame, this);
+        if (heal)
+                AFR_STACK_DESTROY (heal);
         return ret;
 }
 
@@ -2601,14 +2624,16 @@ afr_lookup_entry_heal (call_frame_t *frame, xlator_t *this)
 	}
 
 	if (need_heal) {
+		heal = afr_frame_create (this);
+		if (!heal)
+                        goto metadata_heal;
 
-		heal = copy_frame (frame);
-		if (heal)
-			heal->root->pid = GF_CLIENT_PID_SELF_HEALD;
 		ret = synctask_new (this->ctx->env, afr_lookup_selfheal_wrap,
 				    afr_refresh_selfheal_done, heal, frame);
-		if (ret)
+		if (ret) {
+                        AFR_STACK_DESTROY (heal);
 			goto metadata_heal;
+                }
                 return ret;
 	}
 metadata_heal:
@@ -2770,8 +2795,8 @@ afr_discover_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
 
         call_count = afr_frame_return (frame);
         if (call_count == 0) {
-               afr_set_need_heal (this, local);
-               afr_discover_done (frame, this);
+                afr_set_need_heal (this, local);
+                afr_lookup_metadata_heal_check (frame, this);
         }
 
 	return 0;
@@ -2984,7 +3009,7 @@ afr_lookup (call_frame_t *frame, xlator_t *this, loc_t *loc, dict_t *xattr_req)
         void          *gfid_req = NULL;
         int            ret = 0;
 
-	if (!loc->parent && gf_uuid_is_null (loc->pargfid)) {
+        if (loc_is_nameless (loc)) {
                 if (xattr_req)
                         dict_del (xattr_req, "gfid-req");
 		afr_discover (frame, this, loc, xattr_req);
diff --git a/xlators/cluster/afr/src/afr-self-heal.h b/xlators/cluster/afr/src/afr-self-heal.h
index 80e7a68e67b..c501852ba5f 100644
--- a/xlators/cluster/afr/src/afr-self-heal.h
+++ b/xlators/cluster/afr/src/afr-self-heal.h
@@ -153,6 +153,10 @@ int
 afr_selfheal_unlocked_discover (call_frame_t *frame, inode_t *inode,
 				uuid_t gfid, struct afr_reply *replies);
 
+int
+afr_selfheal_unlocked_discover_on (call_frame_t *frame, inode_t *inode,
+                                   uuid_t gfid, struct afr_reply *replies,
+                                   unsigned char *discover_on);
 inode_t *
 afr_selfheal_unlocked_lookup_on (call_frame_t *frame, inode_t *parent,
 				 const char *name, struct afr_reply *replies,