afr: assign gfid during name heal when no 'source' is present.

Problem:
If parent dir is in split-brain or has dirty xattrs set, and the file
has gfid missing on one of the bricks, then name heal won't assign the
gfid.

Fix:
Use the brick we select the gfid from as the 'source'.

Note: Problem was found while trying to debug a split-brain issue on
Cynthia Zhou's setup.

updates: bz#1637249
Change-Id: Id088d4f0fb017aa35122de426654194e581ed742
Reported-by: Cynthia Zhou <cynthia.zhou@nokia-sbell.com>
Signed-off-by: Ravishankar N <ravishankar@redhat.com>

4 files changed, 52 insertions, 52 deletions

diff --git a/xlators/cluster/afr/src/afr-self-heal-common.c b/xlators/cluster/afr/src/afr-self-heal-common.c
index 8635b3e9e06..7a96b894cd7 100644
--- a/xlators/cluster/afr/src/afr-self-heal-common.c
+++ b/xlators/cluster/afr/src/afr-self-heal-common.c
@@ -21,7 +21,7 @@ afr_heal_synctask(xlator_t *this, afr_local_t *local);
 int
 afr_lookup_and_heal_gfid(xlator_t *this, inode_t *parent, const char *name,
                          inode_t *inode, struct afr_reply *replies, int source,
-                         unsigned char *sources, void *gfid)
+                         unsigned char *sources, void *gfid, int *gfid_idx)
 {
     afr_private_t *priv = NULL;
     call_frame_t *frame = NULL;
@@ -37,15 +37,30 @@ afr_lookup_and_heal_gfid(xlator_t *this, inode_t *parent, const char *name,
 
     priv = this->private;
     wind_on = alloca0(priv->child_count);
-    ia_type = replies[source].poststat.ia_type;
-    if ((ia_type == IA_INVAL) &&
-        (AFR_COUNT(sources, priv->child_count) == priv->child_count)) {
-        /* If a file is present on some bricks of the replica but parent
-         * dir does not have pending xattrs, all bricks are sources and
-         * the 'source' we  selected earlier might be one where the file
-         * is not actually present. Hence check if file is present in
-         * any of the sources.*/
-        for (i = 0; i < priv->child_count; i++) {
+    if (source >= 0 && replies[source].valid && replies[source].op_ret == 0)
+        ia_type = replies[source].poststat.ia_type;
+
+    if (ia_type != IA_INVAL)
+        goto heal;
+
+    /* If ia_type is still invalid, it means either
+     * (a)'source' was -1, i.e. parent dir pending xattrs are in split-brain
+     * (or) (b) The parent dir pending xattrs are all zeroes (i.e. all bricks
+     * are sources) and the 'source' we selected earlier might be the one where
+     * the file is not actually present.
+     *
+     * In both cases, let us pick a brick with a successful reply and use its
+     * ia_type.
+     * */
+    for (i = 0; i < priv->child_count; i++) {
+        if (source == -1) {
+            /* case (a) above. */
+            if (replies[i].valid && replies[i].op_ret == 0) {
+                ia_type = replies[i].poststat.ia_type;
+                break;
+            }
+        } else {
+            /* case (b) above. */
             if (i == source)
                 continue;
             if (sources[i] && replies[i].valid && replies[i].op_ret == 0) {
@@ -55,6 +70,7 @@ afr_lookup_and_heal_gfid(xlator_t *this, inode_t *parent, const char *name,
         }
     }
 
+heal:
     /* gfid heal on those subvolumes that do not have gfid associated
      * with the inode and update those replies.
      */
@@ -103,7 +119,22 @@ afr_lookup_and_heal_gfid(xlator_t *this, inode_t *parent, const char *name,
         afr_reply_wipe(&replies[i]);
         afr_reply_copy(&replies[i], &local->replies[i]);
     }
+    if (gfid_idx && (*gfid_idx == -1)) {
+        /*Pick a brick where the gifd heal was successful.*/
+        for (i = 0; i < priv->child_count; i++) {
+            if (!wind_on[i])
+                continue;
+            if (replies[i].valid && replies[i].op_ret == 0 &&
+                !gf_uuid_is_null(replies[i].poststat.ia_gfid)) {
+                *gfid_idx = i;
+                break;
+            }
+        }
+    }
 out:
+    if (gfid_idx && (*gfid_idx == -1) && (ret == 0)) {
+        ret = -afr_final_errno(local, priv);
+    }
     loc_wipe(&loc);
     if (frame)
         AFR_STACK_DESTROY(frame);
diff --git a/xlators/cluster/afr/src/afr-self-heal-entry.c b/xlators/cluster/afr/src/afr-self-heal-entry.c
index 619558e94b7..fb6952c10fd 100644
--- a/xlators/cluster/afr/src/afr-self-heal-entry.c
+++ b/xlators/cluster/afr/src/afr-self-heal-entry.c
@@ -192,7 +192,7 @@ __afr_selfheal_heal_dirent(call_frame_t *frame, xlator_t *this, fd_t *fd,
     if (replies[source].op_ret == 0) {
         ret = afr_lookup_and_heal_gfid(this, fd->inode, name, inode, replies,
                                        source, sources,
-                                       &replies[source].poststat.ia_gfid);
+                                       &replies[source].poststat.ia_gfid, NULL);
         if (ret)
             return ret;
     }
@@ -319,7 +319,7 @@ __afr_selfheal_merge_dirent(call_frame_t *frame, xlator_t *this, fd_t *fd,
 
     ret = afr_lookup_and_heal_gfid(this, fd->inode, name, inode, replies,
                                    source, sources,
-                                   &replies[source].poststat.ia_gfid);
+                                   &replies[source].poststat.ia_gfid, NULL);
     if (ret)
         return ret;
 
diff --git a/xlators/cluster/afr/src/afr-self-heal-name.c b/xlators/cluster/afr/src/afr-self-heal-name.c
index 39aacee6ecf..aa20ad1b835 100644
--- a/xlators/cluster/afr/src/afr-self-heal-name.c
+++ b/xlators/cluster/afr/src/afr-self-heal-name.c
@@ -18,7 +18,8 @@ __afr_selfheal_assign_gfid(xlator_t *this, inode_t *parent, uuid_t pargfid,
                            const char *bname, inode_t *inode,
                            struct afr_reply *replies, void *gfid,
                            unsigned char *locked_on, int source,
-                           unsigned char *sources, gf_boolean_t is_gfid_absent)
+                           unsigned char *sources, gf_boolean_t is_gfid_absent,
+                           int *gfid_idx)
 {
     int ret = 0;
     int up_count = 0;
@@ -46,8 +47,8 @@ __afr_selfheal_assign_gfid(xlator_t *this, inode_t *parent, uuid_t pargfid,
         }
     }
 
-    afr_lookup_and_heal_gfid(this, parent, bname, inode, replies, source,
-                             sources, gfid);
+    ret = afr_lookup_and_heal_gfid(this, parent, bname, inode, replies, source,
+                                   sources, gfid, gfid_idx);
 
 out:
     return ret;
@@ -146,35 +147,6 @@ __afr_selfheal_name_expunge(xlator_t *this, inode_t *parent, uuid_t pargfid,
     return ret;
 }
 
-/* This function is to be called after ensuring that there is no gfid mismatch
- * for the inode across multiple sources
- */
-static int
-afr_selfheal_gfid_idx_get(xlator_t *this, struct afr_reply *replies,
-                          unsigned char *sources)
-{
-    int i = 0;
-    int gfid_idx = -1;
-    afr_private_t *priv = NULL;
-
-    priv = this->private;
-
-    for (i = 0; i < priv->child_count; i++) {
-        if (!replies[i].valid || replies[i].op_ret != 0)
-            continue;
-
-        if (!sources[i])
-            continue;
-
-        if (gf_uuid_is_null(replies[i].poststat.ia_gfid))
-            continue;
-
-        gfid_idx = i;
-        break;
-    }
-    return gfid_idx;
-}
-
 static gf_boolean_t
 afr_selfheal_name_need_heal_check(xlator_t *this, struct afr_reply *replies)
 {
@@ -400,21 +372,18 @@ __afr_selfheal_name_do(call_frame_t *frame, xlator_t *this, inode_t *parent,
         gfid = gfid_req;
     } else {
         gfid = &replies[gfid_idx].poststat.ia_gfid;
+        if (source == -1)
+            /* Either entry split-brain or dirty xattrs are present on parent.*/
+            source = gfid_idx;
     }
 
     is_gfid_absent = (gfid_idx == -1) ? _gf_true : _gf_false;
     ret = __afr_selfheal_assign_gfid(this, parent, pargfid, bname, inode,
                                      replies, gfid, locked_on, source, sources,
-                                     is_gfid_absent);
+                                     is_gfid_absent, &gfid_idx);
     if (ret)
         return ret;
 
-    if (gfid_idx == -1) {
-        gfid_idx = afr_selfheal_gfid_idx_get(this, replies, sources);
-        if (gfid_idx == -1)
-            return -1;
-    }
-
     ret = __afr_selfheal_name_impunge(frame, this, parent, pargfid, bname,
                                       inode, replies, gfid_idx);
     if (ret == -EIO)
diff --git a/xlators/cluster/afr/src/afr-self-heal.h b/xlators/cluster/afr/src/afr-self-heal.h
index 9c7418c7169..41adbe05dc8 100644
--- a/xlators/cluster/afr/src/afr-self-heal.h
+++ b/xlators/cluster/afr/src/afr-self-heal.h
@@ -119,7 +119,7 @@ afr_selfheal_entry(call_frame_t *frame, xlator_t *this, inode_t *inode);
 int
 afr_lookup_and_heal_gfid(xlator_t *this, inode_t *parent, const char *name,
                          inode_t *inode, struct afr_reply *replies, int source,
-                         unsigned char *sources, void *gfid);
+                         unsigned char *sources, void *gfid, int *gfid_idx);
 
 int
 afr_selfheal_inodelk(call_frame_t *frame, xlator_t *this, inode_t *inode,