qemu/include/block
Eric Blake 7423f41782 nbd: Limit nbdflags to 16 bits
Rather than asserting that nbdflags is within range, just give
it the correct type to begin with :)  nbdflags corresponds to
the per-export portion of NBD Protocol "transmission flags", which
is 16 bits in response to NBD_OPT_EXPORT_NAME and NBD_OPT_GO.

Furthermore, upstream NBD has never passed the global flags to
the kernel via ioctl(NBD_SET_FLAGS) (the ioctl was first
introduced in NBD 2.9.22; then a latent bug in NBD 3.1 actually
tried to OR the global flags with the transmission flags, with
the disaster that the addition of NBD_FLAG_NO_ZEROES in 3.9
caused all earlier NBD 3.x clients to treat every export as
read-only; NBD 3.10 and later intentionally clip things to 16
bits to pass only transmission flags).  Qemu should follow suit,
since the current two global flags (NBD_FLAG_FIXED_NEWSTYLE
and NBD_FLAG_NO_ZEROES) have no impact on the kernel's behavior
during transmission.

CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>

Message-Id: <1469129688-22848-3-git-send-email-eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-08-03 18:44:56 +02:00
..
accounting.h Use scripts/clean-includes to drop redundant qemu/typedefs.h 2016-03-22 22:20:16 +01:00
aio.h AioContext: correct comments 2016-07-26 17:46:37 +02:00
block_int.h Pull request 2016-07-21 11:00:36 +01:00
block.h block: Convert bdrv_aio_discard() to byte-based 2016-07-20 14:11:55 +01:00
blockjob.h blockjob: Add 'job_id' parameter to block_job_create() 2016-07-13 13:26:02 +02:00
dirty-bitmap.h dirty-bitmap: operate with int64_t amount 2016-07-19 16:54:46 -04:00
nbd.h nbd: Limit nbdflags to 16 bits 2016-08-03 18:44:56 +02:00
qapi.h block/qapi: Use blk_enable_write_cache() 2016-03-30 12:16:02 +02:00
raw-aio.h linux-aio: share one LinuxAioState within an AioContext 2016-07-18 15:09:31 +01:00
scsi.h * SCSI scanner support 2016-07-14 13:44:06 +01:00
snapshot.h include: Clean up includes 2016-02-23 12:43:05 +00:00
thread-pool.h Clean up decorations and whitespace around header guards 2016-07-12 16:20:46 +02:00
throttle-groups.h block: Move I/O throttling configuration functions to BlockBackend 2016-05-19 16:45:30 +02:00
write-threshold.h Use scripts/clean-includes to drop redundant qemu/typedefs.h 2016-03-22 22:20:16 +01:00