cluster/dht : Ftruncate on migrating file fails with EINVAL

What:
If dht_open is called on a migrating file after the inode_ctx is set,
subsequent FOPs on that fd do not open the fd on the dst subvol.
This is seen when the open-ftruncate-close sequence is repeatedly
called on a migrating file.
A second call to the sequence described above causes dht_truncate_cbk
to call dht_truncate2 as the dht_inode_ctx was already set by the first
call. As dht_rebalance_in_progress_check is not called, the fd is not
opened on the dst subvol.
On a distributed-replicate volume, this causes AFR to
open the fd using afr_fix_open, but with the wrong flags, causing
posix_ftruncate to fail with EINVAL.
The fix: We require fd specific information to make a decision while
handling migrating files.
Set the fd_ctx to indicate the fd has been opened on the dst subvol
and check if it has been set while processing Phase1/Phase2 checks
in the FOP callback functions.

> Change-Id: I43cdcd8017b4a11e18afdd210469de7cd9a5ef14
> Signed-off-by: N Balachandran <nbalacha@redhat.com>
> Reviewed-on: http://review.gluster.org/12985
> Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
> Tested-by: Gluster Build System <jenkins@build.gluster.com>
> Reviewed-by: Dan Lambright <dlambrig@redhat.com>
> Tested-by: Dan Lambright <dlambrig@redhat.com>

Change-Id: I99f8aceec105f16631def06a263f0561954d14b3
BUG: 1293827
Signed-off-by: N Balachandran <nbalacha@redhat.com>
Reviewed-on: http://review.gluster.org/13071
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Tested-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Smoke: Gluster Build System <jenkins@build.gluster.com>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.com>

1 files changed, 28 insertions, 16 deletions

diff --git a/xlators/cluster/dht/src/dht-inode-write.c b/xlators/cluster/dht/src/dht-inode-write.c
index e57056b4f77..e54b3fba584 100644
--- a/xlators/cluster/dht/src/dht-inode-write.c
+++ b/xlators/cluster/dht/src/dht-inode-write.c
@@ -94,8 +94,10 @@ dht_writev_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                                                   &subvol1, &subvol2);
                 if (!dht_mig_info_is_invalid (local->cached_subvol,
                                               subvol1, subvol2)) {
-                        dht_writev2 (this, subvol2, frame, 0);
-                        return 0;
+                        if (dht_fd_open_on_dst (this, local->fd, subvol2)) {
+                                dht_writev2 (this, subvol2, frame, 0);
+                                return 0;
+                        }
                 }
                 ret = dht_rebalance_in_progress_check (this, frame);
                 if (!ret)
@@ -212,12 +214,12 @@ dht_truncate_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                   int op_ret, int op_errno, struct iatt *prebuf,
                   struct iatt *postbuf, dict_t *xdata)
 {
-        dht_local_t  *local = NULL;
-        call_frame_t *prev = NULL;
-        int           ret = -1;
-        xlator_t    *src_subvol = NULL;
-        xlator_t    *dst_subvol = NULL;
-        inode_t      *inode = NULL;
+        dht_local_t  *local      = NULL;
+        call_frame_t *prev       = NULL;
+        int           ret        = -1;
+        xlator_t     *src_subvol = NULL;
+        xlator_t     *dst_subvol = NULL;
+        inode_t      *inode      = NULL;
 
         GF_VALIDATE_OR_GOTO ("dht", frame, err);
         GF_VALIDATE_OR_GOTO ("dht", this, out);
@@ -267,14 +269,18 @@ dht_truncate_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
         if (IS_DHT_MIGRATION_PHASE1 (postbuf)) {
                 dht_iatt_merge (this, &local->stbuf, postbuf, NULL);
                 dht_iatt_merge (this, &local->prebuf, prebuf, NULL);
+
                 inode = (local->fd) ? local->fd->inode : local->loc.inode;
 
                 dht_inode_ctx_get_mig_info (this, inode, &src_subvol,
                                             &dst_subvol);
                 if (!dht_mig_info_is_invalid (local->cached_subvol,
                                               src_subvol, dst_subvol)) {
-                        dht_truncate2 (this, dst_subvol, frame, 0);
-                        return 0;
+                        if ((!local->fd) || ((local->fd) &&
+                            dht_fd_open_on_dst (this, local->fd, dst_subvol))) {
+                                dht_truncate2 (this, dst_subvol, frame, 0);
+                                return 0;
+                        }
                 }
                 ret = dht_rebalance_in_progress_check (this, frame);
                 if (!ret)
@@ -480,8 +486,10 @@ dht_fallocate_cbk(call_frame_t *frame, void *cookie, xlator_t *this,
                                             &dst_subvol);
                 if (!dht_mig_info_is_invalid (local->cached_subvol,
                                               src_subvol, dst_subvol)) {
-                        dht_fallocate2 (this, dst_subvol, frame, 0);
-                        return 0;
+                        if (dht_fd_open_on_dst (this, local->fd, dst_subvol)) {
+                                dht_fallocate2 (this, dst_subvol, frame, 0);
+                                return 0;
+                        }
                 }
                 ret = dht_rebalance_in_progress_check (this, frame);
                 if (!ret)
@@ -643,8 +651,10 @@ dht_discard_cbk(call_frame_t *frame, void *cookie, xlator_t *this,
                                             &dst_subvol);
                 if (!dht_mig_info_is_invalid(local->cached_subvol,
                                              src_subvol, dst_subvol)) {
-                        dht_discard2 (this, dst_subvol, frame, 0);
-                        return 0;
+                        if (dht_fd_open_on_dst (this, local->fd, dst_subvol)) {
+                                dht_discard2 (this, dst_subvol, frame, 0);
+                                return 0;
+                        }
                 }
                 ret = dht_rebalance_in_progress_check (this, frame);
                 if (!ret)
@@ -801,8 +811,10 @@ dht_zerofill_cbk(call_frame_t *frame, void *cookie, xlator_t *this,
                                                   &subvol1, &subvol2);
                 if (!dht_mig_info_is_invalid (local->cached_subvol,
                                               subvol1, subvol2)) {
-                        dht_zerofill2 (this, subvol2, frame, 0);
-                        return 0;
+                        if (dht_fd_open_on_dst (this, local->fd, subvol2)) {
+                                dht_zerofill2 (this, subvol2, frame, 0);
+                                return 0;
+                        }
                 }
 
                 ret = dht_rebalance_in_progress_check (this, frame);