Bug 1128593

Description of problem:
===========================
In a distribute-replicate volume, when a brick device crashes, on the fuse mount logs we see lot following warning messages. 

[2014-08-08 12:10:36.262063] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23185 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.263401] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23185 (00000000-0000-0000-0000-000000000000)

lookup's are referring to null GFID's for the given path. 

Version-Release number of selected component (if applicable):
================================================================
glusterfs 3.6.0.27 built on Aug  4 2014 11:49:58

How reproducible:
====================
Often

Steps to Reproduce:
=======================
1. Create a 2 x 2 distribute-replicate volume with 4 bricks . 1 brick per storage node. Start the volume.

2. Create fuse mount. Start creating files and dirs from fuse mount. 

3. While create's are in progress, crash brick1 and brick3 disk.


Actual results:
==================
[2014-08-08 12:10:36.281559] E [afr-self-heal-entry.c:2348:afr_sh_post_nonblocking_entry_cbk] 0-vol1-replicate-1: Non Blocking entrylks failed for /.
[2014-08-08 12:10:36.281604] E [afr-self-heal-common.c:2869:afr_log_self_heal_completion_status] 0-vol1-replicate-1:  entry self heal  failed,   on /
[2014-08-08 12:10:36.282385] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.283113] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.283793] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.284334] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.285025] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.285542] W [client-rpc-fops.c:2761:client3_3_lookup_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186 (00000000-0000-0000-0000-000000000000)
[2014-08-08 12:10:36.286404] W [client-rpc-fops.c:306:client3_3_mkdir_cbk] 0-vol1-client-2: remote operation failed: Input/output error. Path: /test_dir.23186


Expected results:
================
path shouldn't have null gfid's. 

Additional info:
====================
root@mia [Aug-11-2014-13:05:57] >gluster v info
 
Volume Name: vol1
Type: Distributed-Replicate
Volume ID: 18aee4e3-8177-4756-aebc-a759d9b32fa0
Status: Started
Snap Volume: no
Number of Bricks: 2 x 2 = 4
Transport-type: tcp
Bricks:
Brick1: rhs-client11:/rhs/device0/b1
Brick2: rhs-client12:/rhs/device0/b2
Brick3: rhs-client13:/rhs/device0/b3
Brick4: rhs-client14:/rhs/device0/b4
Options Reconfigured:
features.barrier: disable
performance.readdir-ahead: on
auto-delete: disable
snap-max-soft-limit: 90
snap-max-hard-limit: 256
root@mia [Aug-11-2014-13:06:01] >