feature/bitrot: Fix recovery of corrupted hardlink

Problem:
When a file with hardlink is corrupted in ec volume,
the recovery steps mentioned was not working.
Only name and metadata was healing but not the data.

Cause:
The bad file marker in the inode context is not removed.
Hence when self heal tries to open the file for data
healing, it fails with EIO.

Background:
The bitrot deletes inode context during forget.

Briefly, the recovery steps involves following steps.
   1. Delete the entry marked with bad file xattr
      from backend. Delete all the hardlinks including
      .glusters hardlink as well.
   2. Access the each hardlink of the file including
      original from the mount.

The step 2 will send lookup to the brick where the files
are deleted from backend and returns with ENOENT. On
ENOENT, server xlator forgets the inode if there are
no dentries associated with it. But in case hardlinks,
the forget won't be called as dentries (other hardlink
files) are associated with the inode. Hence bitrot stube
won't delete it's context failing the data self heal.

Fix:
Bitrot-stub should delete the inode context on getting
ENOENT during lookup.

>Change-Id: Ice6adc18625799e7afd842ab33b3517c2be264c1
>BUG: 1373520
>Signed-off-by: Kotresh HR <khiremat@redhat.com>
>Reviewed-on: http://review.gluster.org/15408
>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 Bhat <raghavendra@redhat.com>
(cherry picked from commit b86a7de9b5ea9dcd0a630dbe09fce6d9ad0d8944)


Change-Id: Ice6adc18625799e7afd842ab33b3517c2be264c1
BUG: 1374565
Signed-off-by: Kotresh HR <khiremat@redhat.com>
Reviewed-on: http://review.gluster.org/15433
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 Bhat <raghavendra@redhat.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/xlators/features/bit-rot/src/stub/bit-rot-stub.c b/xlators/features/bit-rot/src/stub/bit-rot-stub.c
index 67103f6b5e1..4e01f5c86b1 100644
--- a/xlators/features/bit-rot/src/stub/bit-rot-stub.c
+++ b/xlators/features/bit-rot/src/stub/bit-rot-stub.c
@@ -2631,6 +2631,18 @@ br_stub_handle_lookup_error (xlator_t *this, inode_t *inode, int32_t op_errno)
         }
         UNLOCK (&inode->lock);
 
+        if (__br_stub_is_bad_object (ctx)) {
+                /* File is not present, might be deleted for recovery,
+                 * del the bitrot inode context
+                 */
+                ctx_addr = 0;
+                inode_ctx_del (inode, this, &ctx_addr);
+                if (ctx_addr) {
+                        ctx = (br_stub_inode_ctx_t *)(long)ctx_addr;
+                        GF_FREE (ctx);
+                }
+        }
+
 out:
         return;
 }