change ha-statfs() to handle the case of loc->inode being NULL

This fix is needed in ha_statfs(), as the current code doesn't handle
the case of loc->inode being NULL, which is a valid case in statfs()
[Remember its stateless call]. This was causing 100% disk full logs in
distribute or nufa as the logic of checking whether the subvolumes have
enough disk space on them used to fail.

Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

2 files changed, 44 insertions, 27 deletions

diff --git a/xlators/cluster/ha/src/ha.c b/xlators/cluster/ha/src/ha.c
index e7391eeade1..b938071edde 100644
--- a/xlators/cluster/ha/src/ha.c
+++ b/xlators/cluster/ha/src/ha.c
@@ -2365,15 +2365,27 @@ ha_statfs_cbk (call_frame_t *frame,
 	       int32_t op_errno,
 	       struct statvfs *buf)
 {
-	int ret = -1;
-
-	ret = ha_handle_cbk (frame, cookie, op_ret, op_errno);
-	if (ret == 0) {
-		STACK_UNWIND (frame,
-			      op_ret,
-			      op_errno,
-			      buf);
-	}
+        ha_local_t   *local = NULL;
+        ha_private_t *priv  = NULL;
+
+        local = frame->local;
+        if (-1 == op_ret) {
+                local->active = (local->active + 1) % priv->child_count;
+                local->tries--;
+                if (!local->tries)
+                        goto out;
+                
+                STACK_WIND (frame, ha_statfs_cbk,
+                            HA_ACTIVE_CHILD(this, local),
+                            HA_ACTIVE_CHILD(this, local)->fops->statfs, 
+                            &local->loc);
+                return 0;
+        }
+
+ out:
+        loc_wipe (&local->loc);
+        STACK_UNWIND (frame, op_ret, op_errno, buf);
+        
 	return 0;
 }
 
@@ -2382,23 +2394,28 @@ ha_statfs (call_frame_t *frame,
 	   xlator_t *this,
 	   loc_t *loc)
 {
-	ha_local_t *local = NULL;
-	int op_errno = 0;
-
-	op_errno = ha_alloc_init_inode (frame, loc->inode);
-	if (op_errno < 0) {
-		op_errno = -op_errno;
-		goto err;
-	}
-	local = frame->local;
-
-	local->stub = fop_statfs_stub (frame, ha_statfs, loc);
-	STACK_WIND_COOKIE (frame,
-			   ha_statfs_cbk,
-			   (void *)(long)local->active,
-			   HA_ACTIVE_CHILD(this, local),
-			   HA_ACTIVE_CHILD(this, local)->fops->statfs,
-			   loc);
+        ha_private_t *priv = NULL;
+	ha_local_t   *local = NULL;
+	int           op_errno = 0;
+
+        /* The normal way of handling failover doesn't work here
+         * as loc->inode may be null in this case.
+         */
+        local = CALLOC (1, sizeof (*local));
+        if (!local) {
+                op_errno = ENOMEM;
+                goto err;
+        }
+        priv = this->private;
+        frame->local  = local;
+        local->active = priv->pref_subvol;
+        if (-1 == local->active)
+                local->active = 0;
+        local->tries  = priv->child_count;
+        loc_copy (&local->loc, loc);
+
+	STACK_WIND (frame, ha_statfs_cbk, HA_ACTIVE_CHILD(this, local),
+                    HA_ACTIVE_CHILD(this, local)->fops->statfs, loc);
 	return 0;
 err:
 	STACK_UNWIND (frame, -1, op_errno, NULL);
diff --git a/xlators/cluster/ha/src/ha.h b/xlators/cluster/ha/src/ha.h
index 7e4898ceb90..d47d965355e 100644
--- a/xlators/cluster/ha/src/ha.h
+++ b/xlators/cluster/ha/src/ha.h
@@ -27,7 +27,7 @@ typedef struct {
 	int32_t call_count;
 	char *state, *pattern;
 	dict_t *dict;
-	loc_t *loc;
+	loc_t loc;
 	struct stat buf;
 	fd_t *fd;
 	inode_t *inode;