tree 4a7af69e0a6d8b74f17c0034b173bc45896d8f08
parent dff4982f5cd4e30e2a140a3bca95d8814115bf5b
author Paul Clements <paul.clements@steeleye.com> 1192602456 -0700
committer Linus Torvalds <torvalds@woody.linux-foundation.org> 1192635775 -0700

NBD: set uninitialized devices to size 0

This fixes errors with utilities (such as LVM's vgscan) that try to scan all
devices.  Previously this would generate read errors when uninitialized nbd
devices were scanned:

# vgscan
   Reading all physical volumes.  This may take a while...
   /dev/nbd0: read failed after 0 of 1024 at 0: Input/output error
   /dev/nbd0: read failed after 0 of 1024 at 509804544: Input/output error
   /dev/nbd0: read failed after 0 of 2048 at 0: Input/output error
   /dev/nbd1: read failed after 0 of 1024 at 509804544: Input/output error
   /dev/nbd1: read failed after 0 of 2048 at 0: Input/output error

 From now on, uninitialized nbd devices will have size zero, which
prevents these errors.

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