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
BUG: 1284823
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>

1 files changed, 20 insertions, 4 deletions

diff --git a/xlators/cluster/dht/src/dht-common.h b/xlators/cluster/dht/src/dht-common.h
index 70e5e15c0d8..9fc0d402d6f 100644
--- a/xlators/cluster/dht/src/dht-common.h
+++ b/xlators/cluster/dht/src/dht-common.h
@@ -547,6 +547,13 @@ typedef struct dht_migrate_info {
 } dht_migrate_info_t;
 
 
+
+typedef struct dht_fd_ctx {
+        uint64_t opened_on_dst;
+        GF_REF_DECL;
+} dht_fd_ctx_t;
+
+
 #define ENTRY_MISSING(op_ret, op_errno) (op_ret == -1 && op_errno == ENOENT)
 
 #define is_revalidate(loc) (dht_inode_ctx_layout_get (loc->inode, this, NULL) == 0)
@@ -1131,11 +1138,20 @@ int
 dht_build_parent_loc (xlator_t *this, loc_t *parent, loc_t *child,
                                                  int32_t *op_errno);
 
-int32_t dht_set_local_rebalance (xlator_t *this, dht_local_t *local,
-                                 struct iatt *stbuf,
-                                 struct iatt *prebuf,
-                                 struct iatt *postbuf, dict_t *xdata);
+int32_t
+dht_set_local_rebalance (xlator_t *this, dht_local_t *local,
+                         struct iatt *stbuf,
+                         struct iatt *prebuf,
+                         struct iatt *postbuf, dict_t *xdata);
 void
 dht_build_root_loc (inode_t *inode, loc_t *loc);
 
+gf_boolean_t
+dht_fd_open_on_dst (xlator_t *this, fd_t *fd, xlator_t *dst);
+
+int32_t
+dht_fd_ctx_destroy (xlator_t *this, fd_t *fd);
+
+int32_t
+dht_release (xlator_t *this, fd_t *fd);
 #endif/* _DHT_H */