quota: enhancement of build ancestry

There can a small race window where marker accounting will
be missed.
Consider below example where NFS mount is used
and bricks are restarted and a write operation is performed

Currently:
T1: lookup from protocol server, quota will initiate ancestry build
T2: opendir FOP from ancestry build
T3: write FOP from client
T4: write_cbk
T5: marker initiate accounting.
    There will be a problem here and txn aborts,
    because build_ancestry is not complete
    and parent not found for an inode
T6: opendir_cbk
T7: initiate readdirp, posix builds ancestry in readdirp


With this patch, now calling readdirp on anonoymous fd 
during build ancestry:

T1: lookup from protocol server, quota will initiate ancestry build
T2: readirp FOP from ancestry build, posix builds ancestry in 
    readdirp 
T3: write FOP from client
T4: write_cbk
T5: marker initiate accounting. 
    No problem here as build ancestry was performed at T1


Change-Id: I2c262c86f34f6c574940a6b8772d94f2bade9465
BUG: 1184885
Signed-off-by: vmallika <vmallika@redhat.com>
Reviewed-on: http://review.gluster.org/9954
Reviewed-by: Vijay Bellur <vbellur@redhat.com>
Tested-by: Vijay Bellur <vbellur@redhat.com>

0 files changed, 0 insertions, 0 deletions