From b54197c43db88f4436717f554d623189cddce29e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 1 May 2014 16:51:50 +0200 Subject: [PATCH] virtio_scsi: use cmd_size Taken almost entirely from Nicholas Bellinger's scsi-mq conversion. Signed-off-by: Christoph Hellwig Acked-by: Paolo Bonzini Reviewed-by: Nicholas Bellinger --- drivers/scsi/virtio_scsi.c | 25 +++++++------------------ include/scsi/scsi_cmnd.h | 9 +++++++++ 2 files changed, 16 insertions(+), 18 deletions(-) diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index fc054935eb1f..d4727b339474 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -199,7 +199,6 @@ static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) set_driver_byte(sc, DRIVER_SENSE); } - mempool_free(cmd, virtscsi_cmd_pool); sc->scsi_done(sc); atomic_dec(&tgt->reqs); @@ -242,8 +241,6 @@ static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf) if (cmd->comp) complete_all(cmd->comp); - else - mempool_free(cmd, virtscsi_cmd_pool); } static void virtscsi_ctrl_done(struct virtqueue *vq) @@ -459,10 +456,9 @@ static int virtscsi_queuecommand(struct virtio_scsi *vscsi, struct virtio_scsi_vq *req_vq, struct scsi_cmnd *sc) { - struct virtio_scsi_cmd *cmd; - int ret; - struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev); + struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc); + BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize); /* TODO: check feature bit and fail if unsupported? */ @@ -471,11 +467,6 @@ static int virtscsi_queuecommand(struct virtio_scsi *vscsi, dev_dbg(&sc->device->sdev_gendev, "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); - ret = SCSI_MLQUEUE_HOST_BUSY; - cmd = mempool_alloc(virtscsi_cmd_pool, GFP_ATOMIC); - if (!cmd) - goto out; - memset(cmd, 0, sizeof(*cmd)); cmd->sc = sc; cmd->req.cmd = (struct virtio_scsi_cmd_req){ @@ -494,13 +485,9 @@ static int virtscsi_queuecommand(struct virtio_scsi *vscsi, if (virtscsi_kick_cmd(req_vq, cmd, sizeof cmd->req.cmd, sizeof cmd->resp.cmd, - GFP_ATOMIC) == 0) - ret = 0; - else - mempool_free(cmd, virtscsi_cmd_pool); - -out: - return ret; + GFP_ATOMIC) != 0) + return SCSI_MLQUEUE_HOST_BUSY; + return 0; } static int virtscsi_queuecommand_single(struct Scsi_Host *sh, @@ -642,6 +629,7 @@ static struct scsi_host_template virtscsi_host_template_single = { .name = "Virtio SCSI HBA", .proc_name = "virtio_scsi", .this_id = -1, + .cmd_size = sizeof(struct virtio_scsi_cmd), .queuecommand = virtscsi_queuecommand_single, .eh_abort_handler = virtscsi_abort, .eh_device_reset_handler = virtscsi_device_reset, @@ -658,6 +646,7 @@ static struct scsi_host_template virtscsi_host_template_multi = { .name = "Virtio SCSI HBA", .proc_name = "virtio_scsi", .this_id = -1, + .cmd_size = sizeof(struct virtio_scsi_cmd), .queuecommand = virtscsi_queuecommand_multi, .eh_abort_handler = virtscsi_abort, .eh_device_reset_handler = virtscsi_device_reset, diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index dd7c998221b3..e016e2ac38df 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -133,6 +133,15 @@ struct scsi_cmnd { unsigned char tag; /* SCSI-II queued command tag */ }; +/* + * Return the driver private allocation behind the command. + * Only works if cmd_size is set in the host template. + */ +static inline void *scsi_cmd_priv(struct scsi_cmnd *cmd) +{ + return cmd + 1; +} + /* make sure not to use it with REQ_TYPE_BLOCK_PC commands */ static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) {