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>
48cf6061b3