diff options
| -rw-r--r-- | drivers/block/virtio_blk.c | 30 | ||||
| -rw-r--r-- | include/linux/virtio_blk.h | 15 |
2 files changed, 40 insertions, 5 deletions
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index 73de753..3d5fe97 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -92,15 +92,26 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk, return false; vbr->req = req; - if (blk_fs_request(vbr->req)) { + switch (req->cmd_type) { + case REQ_TYPE_FS: vbr->out_hdr.type = 0; vbr->out_hdr.sector = blk_rq_pos(vbr->req); vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); - } else if (blk_pc_request(vbr->req)) { + break; + case REQ_TYPE_BLOCK_PC: vbr->out_hdr.type = VIRTIO_BLK_T_SCSI_CMD; vbr->out_hdr.sector = 0; vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); - } else { + break; + case REQ_TYPE_LINUX_BLOCK: + if (req->cmd[0] == REQ_LB_OP_FLUSH) { + vbr->out_hdr.type = VIRTIO_BLK_T_FLUSH; + vbr->out_hdr.sector = 0; + vbr->out_hdr.ioprio = req_get_ioprio(vbr->req); + break; + } + /*FALLTHRU*/ + default: /* We don't put anything else in the queue. */ BUG(); } @@ -200,6 +211,12 @@ out: return err; } +static void virtblk_prepare_flush(struct request_queue *q, struct request *req) +{ + req->cmd_type = REQ_TYPE_LINUX_BLOCK; + req->cmd[0] = REQ_LB_OP_FLUSH; +} + static int virtblk_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, unsigned long data) { @@ -338,7 +355,10 @@ static int __devinit virtblk_probe(struct virtio_device *vdev) index++; /* If barriers are supported, tell block layer that queue is ordered */ - if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER)) + if (virtio_has_feature(vdev, VIRTIO_BLK_F_FLUSH)) + blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_DRAIN_FLUSH, + virtblk_prepare_flush); + else if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER)) blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL); /* If disk is read-only in the host, the guest should obey */ @@ -425,7 +445,7 @@ static struct virtio_device_id id_table[] = { static unsigned int features[] = { VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX, VIRTIO_BLK_F_GEOMETRY, VIRTIO_BLK_F_RO, VIRTIO_BLK_F_BLK_SIZE, - VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_IDENTIFY + VIRTIO_BLK_F_SCSI, VIRTIO_BLK_F_IDENTIFY, VIRTIO_BLK_F_FLUSH }; /* diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h index 25fbabf..15cb666 100644 --- a/include/linux/virtio_blk.h +++ b/include/linux/virtio_blk.h @@ -14,6 +14,7 @@ #define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/ #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ #define VIRTIO_BLK_F_IDENTIFY 8 /* ATA IDENTIFY supported */ +#define VIRTIO_BLK_F_FLUSH 9 /* Cache flush command support */ #define VIRTIO_BLK_ID_BYTES (sizeof(__u16[256])) /* IDENTIFY DATA */ @@ -35,6 +36,17 @@ struct virtio_blk_config { __u8 identify[VIRTIO_BLK_ID_BYTES]; } __attribute__((packed)); +/* + * Command types + * + * Usage is a bit tricky as some bits are used as flags and some are not. + * + * Rules: + * VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or + * VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own + * and may not be combined with any of the other flags. + */ + /* These two define direction. */ #define VIRTIO_BLK_T_IN 0 #define VIRTIO_BLK_T_OUT 1 @@ -42,6 +54,9 @@ struct virtio_blk_config { /* This bit says it's a scsi command, not an actual read or write. */ #define VIRTIO_BLK_T_SCSI_CMD 2 +/* Cache flush command */ +#define VIRTIO_BLK_T_FLUSH 4 + /* Barrier before this op. */ #define VIRTIO_BLK_T_BARRIER 0x80000000 |