tree bba7827177587a17160c29392651aa27aa7f98fd
parent 8c4dd6068221cd1d0d90490ace80eb4344914a8c
author Laurent Vivier <Laurent.Vivier@bull.net> 1209456166 -0700
committer Linus Torvalds <torvalds@linux-foundation.org> 1209481583 -0700

NBD: allow nbd to be used locally

This patch allows Network Block Device to be mounted locally (nbd-client to
nbd-server over 127.0.0.1).

It creates a kthread to avoid the deadlock described in NBD tools
documentation.  So, if nbd-client hangs waiting for pages, the kblockd thread
can continue its work and free pages.

I have tested the patch to verify that it avoids the hang that always occurs
when writing to a localhost nbd connection.  I have also tested to verify that
no performance degradation results from the additional thread and queue.

Patch originally from Laurent Vivier.

Signed-off-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>