aoe: user can ask driver to forget previously detected devices

When an AoE device is detected, the kernel is informed, and a new block device
is created.  If the device is unused, the block device corresponding to remote
device that is no longer available may be removed from the system by telling
the aoe driver to "flush" its list of devices.

Without this patch, software like GPFS and LVM may attempt to read from AoE
devices that were discovered earlier but are no longer present, blocking until
the I/O attempt times out.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index aecaac3f2e58..2248ab226576 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -191,6 +191,7 @@ struct aoedev *aoedev_by_aoeaddr(int maj, int min);
 struct aoedev *aoedev_by_sysminor_m(ulong sysminor);
 void aoedev_downdev(struct aoedev *d);
 int aoedev_isbusy(struct aoedev *d);
+int aoedev_flush(const char __user *str, size_t size);
 
 int aoenet_init(void);
 void aoenet_exit(void);