cluster/dht: Pass the req dict instead of NULL in dht_attr2()

This bug was causing VMs to pause during rebalance. When qemu winds
down a STAT, shard fills the trusted.glusterfs.shard.file-size attribute
in the req dict which DHT doesn't wind its STAT fop with upon detecting
the file has undergone migration. As a result shard doesn't find the
value to this key in the unwind path, causing it to fail the STAT
with EINVAL.

Also, the same bug exists in other fops too, which is also fixed in
this patch.

Change-Id: Id7823fd932b4e5a9b8779ebb2b612a399c0ef5f0
BUG: 1440051
Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>
Reviewed-on: https://review.gluster.org/17085
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Raghavendra G <rgowdapp@redhat.com>

1 files changed, 27 insertions, 12 deletions

diff --git a/xlators/cluster/dht/src/dht-inode-read.c b/xlators/cluster/dht/src/dht-inode-read.c
index 58168dec81b..c53662d6740 100644
--- a/xlators/cluster/dht/src/dht-inode-read.c
+++ b/xlators/cluster/dht/src/dht-inode-read.c
@@ -76,7 +76,7 @@ dht_open2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
         if (we_are_not_migrating (ret)) {
                 /* This DHT layer is not migrating the file */
                 DHT_STACK_UNWIND (open, frame, -1, local->op_errno,
-                                  NULL, NULL);
+                                  NULL, local->rebalance.xdata);
                 return 0;
 
         }
@@ -88,7 +88,7 @@ dht_open2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         STACK_WIND_COOKIE (frame, dht_open_cbk, subvol, subvol,
                            subvol->fops->open, &local->loc,
-                           local->rebalance.flags, local->fd, NULL);
+                           local->rebalance.flags, local->fd, local->xattr_req);
         return 0;
 
 out:
@@ -122,6 +122,8 @@ dht_open (call_frame_t *frame, xlator_t *this,
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         local->rebalance.flags = flags;
         local->call_cnt = 1;
@@ -239,10 +241,12 @@ dht_attr2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         if (local->fop == GF_FOP_FSTAT) {
                 STACK_WIND_COOKIE (frame, dht_file_attr_cbk, subvol, subvol,
-                                   subvol->fops->fstat, local->fd, NULL);
+                                   subvol->fops->fstat, local->fd,
+                                   local->xattr_req);
         } else {
                 STACK_WIND_COOKIE (frame, dht_file_attr_cbk, subvol, subvol,
-                                   subvol->fops->stat, &local->loc, NULL);
+                                   subvol->fops->stat, &local->loc,
+                                   local->xattr_req);
         }
 
         return 0;
@@ -325,6 +329,8 @@ dht_stat (call_frame_t *frame, xlator_t *this, loc_t *loc, dict_t *xdata)
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         if (IA_ISREG (loc->inode->ia_type)) {
                 local->call_cnt = 1;
@@ -384,6 +390,8 @@ dht_fstat (call_frame_t *frame, xlator_t *this, fd_t *fd, dict_t *xdata)
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         if (IA_ISREG (fd->inode->ia_type)) {
                 local->call_cnt = 1;
@@ -504,7 +512,7 @@ dht_readv2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         STACK_WIND (frame, dht_readv_cbk, subvol, subvol->fops->readv,
                     local->fd, local->rebalance.size, local->rebalance.offset,
-                    local->rebalance.flags, NULL);
+                    local->rebalance.flags, local->xattr_req);
 
         return 0;
 
@@ -539,6 +547,8 @@ dht_readv (call_frame_t *frame, xlator_t *this,
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         local->rebalance.offset = off;
         local->rebalance.size   = size;
@@ -635,7 +645,7 @@ dht_access2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         STACK_WIND_COOKIE (frame, dht_access_cbk, subvol, subvol,
                            subvol->fops->access, &local->loc,
-                           local->rebalance.flags, NULL);
+                           local->rebalance.flags, local->xattr_req);
 
         return 0;
 
@@ -674,6 +684,8 @@ dht_access (call_frame_t *frame, xlator_t *this, loc_t *loc, int32_t mask,
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         STACK_WIND_COOKIE (frame, dht_access_cbk, subvol, subvol,
                            subvol->fops->access, loc, mask, xdata);
@@ -708,9 +720,6 @@ dht_flush_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
         local->op_ret = op_ret;
         local->op_errno = op_errno;
 
-        if (xdata)
-                local->rebalance.xdata = dict_ref (xdata);
-
         /* If context is set, then send flush() it to the destination */
         dht_inode_ctx_get_mig_info (this, local->fd->inode, NULL, &subvol);
         if (subvol && dht_fd_open_on_dst (this, local->fd, subvol)) {
@@ -751,7 +760,7 @@ dht_flush2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         STACK_WIND (frame, dht_flush_cbk,
                     subvol, subvol->fops->flush, local->fd,
-                    local->rebalance.xdata);
+                    local->xattr_req);
 
         return 0;
 
@@ -785,6 +794,8 @@ dht_flush (call_frame_t *frame, xlator_t *this, fd_t *fd, dict_t *xdata)
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         local->call_cnt = 1;
 
@@ -908,7 +919,7 @@ dht_fsync2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         STACK_WIND_COOKIE (frame, dht_fsync_cbk, subvol, subvol,
                            subvol->fops->fsync, local->fd,
-                           local->rebalance.flags, NULL);
+                           local->rebalance.flags, local->xattr_req);
 
         return 0;
 
@@ -935,6 +946,8 @@ dht_fsync (call_frame_t *frame, xlator_t *this, fd_t *fd, int datasync,
 
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         local->call_cnt = 1;
         local->rebalance.flags = datasync;
@@ -1025,7 +1038,7 @@ dht_lk2 (xlator_t *this, xlator_t *subvol, call_frame_t *frame, int ret)
 
         STACK_WIND (frame, dht_lk_cbk, subvol, subvol->fops->lk, local->fd,
                     local->rebalance.lock_cmd, &local->rebalance.flock,
-                    local->rebalance.xdata);
+                    local->xattr_req);
 
         return 0;
 
@@ -1060,6 +1073,8 @@ dht_lk (call_frame_t *frame, xlator_t *this,
                 op_errno = EINVAL;
                 goto err;
         }
+        if (xdata)
+                local->xattr_req = dict_ref (xdata);
 
         local->rebalance.flock = *flock;
         local->rebalance.lock_cmd = cmd;