Commit b5c0a51e authored by Dariusz Stojaczyk's avatar Dariusz Stojaczyk Committed by Jim Harris
Browse files

bdev_virtio: added UNMAP support 



Current UNMAP implementation supports only
up to 2^32-1 unmapped blocks per request.

Change-Id: Ib473831fa32aaba465f76694afad71137288a73a
Signed-off-by: default avatarDariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-on: https://review.gerrithub.io/377688


Tested-by: default avatarSPDK Automated Test System <sys_sgsw@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent bf5a7293

lib/bdev/virtio/bdev_virtio.c

+44 −1
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ 
#include "spdk/endian.h"

#include "spdk/stdinc.h"

#include "spdk/util.h"

#include "spdk/scsi_spec.h"



#include "spdk_internal/bdev.h"

#include "spdk_internal/log.h"
@@ -160,6 +161,38 @@ bdev_virtio_rw(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io) 
	virtio_xmit_pkts(disk->vdev->vqs[2], vreq);

}



static void

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

{

	struct virtio_scsi_disk *disk = (struct virtio_scsi_disk *)bdev_io->bdev;

	struct virtio_req *vreq = bdev_virtio_init_vreq(ch, bdev_io);

	struct virtio_scsi_cmd_req *req = vreq->iov_req.iov_base;

	struct spdk_scsi_unmap_bdesc *desc;

	uint8_t *buf;

	uint16_t cmd_len = 24; /* 8 byte header + 16 byte descriptor */



	vreq->iov = bdev_io->u.bdev.iovs;

	vreq->iovcnt = bdev_io->u.bdev.iovcnt;



	req->cdb[0] = SPDK_SBC_UNMAP;

	to_be16(&req->cdb[7], cmd_len);



	buf = vreq->iov->iov_base;



	/* header */

	to_be16(&buf[0], cmd_len - 2); /* total length (excluding the length field) */

	to_be16(&buf[2], cmd_len - 8); /* length of block descriptors */

	memset(&buf[4], 0, 4); /* reserved */



	/* single block descriptor */

	desc = (struct spdk_scsi_unmap_bdesc *)&buf[8];

	to_be64(&desc->lba, bdev_io->u.bdev.offset_blocks);

	to_be32(&desc->block_count, bdev_io->u.bdev.num_blocks);

	memset(&desc->reserved, 0, sizeof(desc->reserved));



	virtio_xmit_pkts(disk->vdev->vqs[2], vreq);

}



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

{

	switch (bdev_io->type) {
@@ -173,8 +206,18 @@ static int _bdev_virtio_submit_request(struct spdk_io_channel *ch, struct spdk_b 
	case SPDK_BDEV_IO_TYPE_RESET:

		spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_SUCCESS);

		return 0;

	case SPDK_BDEV_IO_TYPE_FLUSH:

	case SPDK_BDEV_IO_TYPE_UNMAP:

		if (bdev_io->u.bdev.num_blocks > UINT32_MAX) {

			SPDK_ERRLOG("single UNMAP block count must be no bigger than 2^32 - 1\n");

			return -1;

		}

		/* Since we support only bdev_io->u.bdev.num_blocks <= UINT32_MAX

		 * allocate just 24 bytes (8 byte header + 16 byte descriptor).

		 * A single block descriptor can UNMAP at most UINT32_MAX blocks.

		 */

		spdk_bdev_io_get_buf(bdev_io, bdev_virtio_unmap, 24);

		return 0;

	case SPDK_BDEV_IO_TYPE_FLUSH:

	default:

		return -1;

	}