From e467cde238184d1b0923db2cd61ae1c5a6dc15aa Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 22 Oct 2007 11:03:38 +1000 Subject: Block driver using virtio. The block driver uses scatter-gather lists with sg[0] being the request information (struct virtio_blk_outhdr) with the type, sector and inbuf id. The next N sg entries are the bio itself, then the last sg is the status byte. Whether the N entries are in or out depends on whether it's a read or a write. We accept the normal (SCSI) ioctls: they get handed through to the other side which can then handle it or reply that it's unsupported. It's not clear that this actually works in general, since I don't know if blk_pc_request() requests have an accurate rq_data_dir(). Although we try to reply -ENOTTY on unsupported commands, ioctl(fd, CDROMEJECT) returns success to userspace. This needs a separate patch. Signed-off-by: Rusty Russell Cc: Jens Axboe --- drivers/block/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'drivers/block/Kconfig') diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index ce4b1e484e6..4d0119ea9e3 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -425,4 +425,10 @@ config XEN_BLKDEV_FRONTEND block device driver. It communicates with a back-end driver in another domain which drives the actual block device. +config VIRTIO_BLK + tristate "Virtio block driver (EXPERIMENTAL)" + depends on EXPERIMENTAL && VIRTIO + ---help--- + This is the virtual block driver for lguest. Say Y or M. + endif # BLK_DEV -- cgit v1.2.3-70-g09d2