features/bit-rot-stub: versioning of objects in write/truncate fop instead of open

* This patch brings in the changes where object versioning is done in write and
  truncate fops instead of tracking them in open and create fops. This model
  works for both regular and anonymous fds. It also removes the race associated
  with open calls, create and lookups.

  This patch follows the below method for object versioning and notifications:

  Before sending writev on the fd, increase the ongoing
  version first. This makes anonymous fd write similar to the regular
  fd write by having the ongoing version increased before doing the
  write.

  Do following steps to do versioning:
  1) For anonymous fds set the fd context (so that release is invoked) and add
     the fd context to the list maintained in the inode context.
     For regular fds the above think would have been done in open itself.
  2) Increase the on-disk ongoing version
  3) Increase the in memory ongoing version and mark inode as non-dirty
  3) Once versioning is successfully done send write operation. If
     versioning fails, then fail the write fop.
  5) In writev_cbk mark inode as modified.

Change-Id: I7104391bbe076d8fc49b68745d2ec29a6e92476c
BUG: 1207979
Signed-off-by: Raghavendra Bhat <raghavendra@redhat.com>
Reviewed-on: http://review.gluster.org/10233
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/xlators/features/bit-rot/src/bitd/bit-rot.h b/xlators/features/bit-rot/src/bitd/bit-rot.h
index 66515e3213c..bbaf86fa65f 100644
--- a/xlators/features/bit-rot/src/bitd/bit-rot.h
+++ b/xlators/features/bit-rot/src/bitd/bit-rot.h
@@ -152,6 +152,8 @@ struct br_object {
                                            be signed */
         br_child_t *child;              /* object's subvolume */
 
+        int sign_info;
+
         struct list_head list;          /* hook to add to the queue once the
                                            object is expired from timer wheel */
         void *data;
@@ -175,4 +177,8 @@ br_prepare_loc (xlator_t *, br_child_t *, loc_t *, gf_dirent_t *, loc_t *);
 gf_boolean_t
 bitd_is_bad_file (xlator_t *, br_child_t *, loc_t *, fd_t *);
 
+void
+br_trigger_sign (xlator_t *this, br_child_t *child, inode_t *linked_inode,
+                 loc_t *loc, dict_t *xdata);
+
 #endif /* __BIT_ROT_H__ */