cluster/afr: Unwind with correct pre/post parent bufs

RCA:
In case of dir fops create, mknod, mkdir, link, symlink, rename
if the fop fails on read-child then unwinds are happening with
all-zero pre/post iatt-bufs. The bug occurs because the parent
bufs are not saved if the response is not from read-child.

Fix:
Save the pre/post-bufs for the first response. If the response
comes from read-child, overwrite whatever we have cached.

Tests:
Attached the mount process to gdb.
Tested that the unwinds happen with proper pre/post iatt bufs in
the following cases:
1) All success case
2) Failure on read-child
3) Failure on non-read-child
4) Failure on all children.

Tested soft-link self-heal to test the change made in that.
Tested errno ENOTEMPTY for rmdir, rename fops.

Change-Id: I82882423d2d766b4f4a3044203bcb5dbcaee1755
BUG: 845242
Signed-off-by: Pranith Kumar K <pranithk@gluster.com>
Reviewed-on: http://review.gluster.com/3775
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Anand Avati <avati@redhat.com>

1 files changed, 10 insertions, 55 deletions

diff --git a/xlators/cluster/afr/src/afr.h b/xlators/cluster/afr/src/afr.h
index 5ed478c4a..9ae154a3d 100644
--- a/xlators/cluster/afr/src/afr.h
+++ b/xlators/cluster/afr/src/afr.h
@@ -587,85 +587,40 @@ typedef struct _afr_local {
                 /* dir write */
 
                 struct {
-                        fd_t *fd;
-                        dict_t *params;
-                        int32_t flags;
-                        mode_t mode;
                         inode_t *inode;
                         struct iatt buf;
                         struct iatt preparent;
                         struct iatt postparent;
-                        struct iatt read_child_buf;
+                        struct iatt prenewparent;
+                        struct iatt postnewparent;
+                } dir_fop; //common structure for all dir fops
+
+                struct {
+                        fd_t *fd;
+                        dict_t *params;
+                        int32_t flags;
+                        mode_t mode;
                 } create;
 
                 struct {
                         dev_t dev;
                         mode_t mode;
                         dict_t *params;
-                        inode_t *inode;
-                        struct iatt buf;
-                        struct iatt preparent;
-                        struct iatt postparent;
-                        struct iatt read_child_buf;
                 } mknod;
 
                 struct {
                         int32_t mode;
                         dict_t *params;
-                        inode_t *inode;
-                        struct iatt buf;
-                        struct iatt read_child_buf;
-                        struct iatt preparent;
-                        struct iatt postparent;
                 } mkdir;
 
                 struct {
-                        int32_t op_ret;
-                        int32_t op_errno;
-                        struct iatt preparent;
-                        struct iatt postparent;
-                } unlink;
-
-                struct {
-                        int   flags;
-                        int32_t op_ret;
-                        int32_t op_errno;
-                        struct iatt preparent;
-                        struct iatt postparent;
+                        int flags;
                 } rmdir;
 
                 struct {
-                        struct iatt buf;
-                        struct iatt read_child_buf;
-                        struct iatt preoldparent;
-                        struct iatt prenewparent;
-                        struct iatt postoldparent;
-                        struct iatt postnewparent;
-                } rename;
-
-                struct {
-                        inode_t *inode;
-                        struct iatt buf;
-                        struct iatt read_child_buf;
-                        struct iatt preparent;
-                        struct iatt postparent;
-                } link;
-
-                struct {
-                        inode_t *inode;
                         dict_t *params;
-                        struct iatt buf;
-                        struct iatt read_child_buf;
                         char *linkpath;
-                        struct iatt preparent;
-                        struct iatt postparent;
                 } symlink;
-
-                struct {
-                        int32_t flags;
-                        dir_entry_t *entries;
-                        int32_t count;
-                } setdents;
         } cont;
 
         struct {