Commit f84d1a53 authored by Dariusz Stojaczyk's avatar Dariusz Stojaczyk Committed by Jim Harris
Browse files

bdev/virtio/blk: implement read-only 



Support the virtio RO flag, so that read-only devices
will successfully initialize now. Also do not allow
issuing any writes on a read-only device, so we don't
flood it with requests that are to fail.

Change-Id: I6b77f2338e4478a9abf2d5286344f6412d79284c
Signed-off-by: default avatarDariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/393461


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
parent 2e0610a0

lib/bdev/virtio/bdev_virtio_blk.c

+18 −3
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ 
struct virtio_blk_dev {

	struct virtio_dev		vdev;

	struct spdk_bdev		bdev;

	bool				readonly;

};



struct virtio_blk_io_ctx {
@@ -77,7 +78,8 @@ struct bdev_virtio_blk_io_channel { 
#define VIRTIO_BLK_DEV_SUPPORTED_FEATURES		\

	(1ULL << VIRTIO_BLK_F_BLK_SIZE		|	\

	 1ULL << VIRTIO_BLK_F_TOPOLOGY		|	\

	 1ULL << VIRTIO_BLK_F_MQ)

	 1ULL << VIRTIO_BLK_F_MQ		|	\

	 1ULL << VIRTIO_BLK_F_RO)



static int bdev_virtio_initialize(void);

static int bdev_virtio_blk_get_ctx_size(void);
@@ -157,13 +159,19 @@ bdev_virtio_rw(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io) 
static int

_bdev_virtio_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io)

{

	struct virtio_blk_dev *bvdev = bdev_io->bdev->ctxt;



	switch (bdev_io->type) {

	case SPDK_BDEV_IO_TYPE_READ:

		spdk_bdev_io_get_buf(bdev_io, bdev_virtio_rw,

				     bdev_io->u.bdev.num_blocks * bdev_io->bdev->blocklen);

		return 0;

	case SPDK_BDEV_IO_TYPE_WRITE:

		if (bvdev->readonly) {

			spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED);

		} else {

			bdev_virtio_rw(ch, bdev_io);

		}

		return 0;

	case SPDK_BDEV_IO_TYPE_RESET:

		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);
@@ -188,11 +196,14 @@ bdev_virtio_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev 
static bool

bdev_virtio_io_type_supported(void *ctx, enum spdk_bdev_io_type io_type)

{

	struct virtio_blk_dev *bvdev = ctx;



	switch (io_type) {

	case SPDK_BDEV_IO_TYPE_READ:

	case SPDK_BDEV_IO_TYPE_WRITE:

	case SPDK_BDEV_IO_TYPE_RESET:

		return true;

	case SPDK_BDEV_IO_TYPE_WRITE:

		return !bvdev->readonly;

	case SPDK_BDEV_IO_TYPE_FLUSH:

	case SPDK_BDEV_IO_TYPE_UNMAP:

	default:
@@ -352,6 +363,10 @@ virtio_blk_dev_init(struct virtio_blk_dev *bvdev, uint16_t max_queues) 
		host_max_queues = 1;

	}



	if (virtio_dev_has_feature(vdev, VIRTIO_BLK_F_RO)) {

		bvdev->readonly = true;

	}



	if (max_queues == 0) {

		SPDK_ERRLOG("%s: requested 0 request queues (%"PRIu16" available).\n",

			    vdev->name, host_max_queues);