| Message ID | 20200430131904.5847-7-hare@suse.de (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | scsi: enable reserved commands for LLDDs | expand |
On Thu, Apr 30, 2020 at 03:18:29PM +0200, Hannes Reinecke wrote: > From: Hannes Reinecke <hare@suse.com> > > Set two commands aside for TMF, and use reserved commands to issue > TMFs. With that we can drop the TMF memory pool. > > Signed-off-by: Hannes Reinecke <hare@suse.com> > --- > drivers/scsi/virtio_scsi.c | 105 ++++++++++++++++++--------------------------- > 1 file changed, 41 insertions(+), 64 deletions(-) > > diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c > index 0e0910c5b942..26054c29d897 100644 > --- a/drivers/scsi/virtio_scsi.c > +++ b/drivers/scsi/virtio_scsi.c > @@ -35,10 +35,10 @@ > #define VIRTIO_SCSI_MEMPOOL_SZ 64 > #define VIRTIO_SCSI_EVENT_LEN 8 > #define VIRTIO_SCSI_VQ_BASE 2 > +#define VIRTIO_SCSI_RESERVED_CMDS 2 > > /* Command queue element */ > struct virtio_scsi_cmd { > - struct scsi_cmnd *sc; > struct completion *comp; > union { > struct virtio_scsi_cmd_req cmd; > @@ -86,9 +86,6 @@ struct virtio_scsi { > struct virtio_scsi_vq req_vqs[]; > }; > > -static struct kmem_cache *virtscsi_cmd_cache; > -static mempool_t *virtscsi_cmd_pool; > - > static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev) > { > return vdev->priv; > @@ -108,7 +105,7 @@ static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid) > static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) > { > struct virtio_scsi_cmd *cmd = buf; > - struct scsi_cmnd *sc = cmd->sc; > + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); > struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd; > > dev_dbg(&sc->device->sdev_gendev, > @@ -406,7 +403,7 @@ static int __virtscsi_add_cmd(struct virtqueue *vq, > struct virtio_scsi_cmd *cmd, > size_t req_size, size_t resp_size) > { > - struct scsi_cmnd *sc = cmd->sc; > + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); > struct scatterlist *sgs[6], req, resp; > struct sg_table *out, *in; > unsigned out_num = 0, in_num = 0; > @@ -557,8 +554,6 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, > dev_dbg(&sc->device->sdev_gendev, > "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); > > - cmd->sc = sc; > - > BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); > > #ifdef CONFIG_BLK_DEV_INTEGRITY > @@ -590,17 +585,17 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, > static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) > { > DECLARE_COMPLETION_ONSTACK(comp); > - int ret = FAILED; > > cmd->comp = ∁ > + > if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, > sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) > - goto out; > + return FAILED; > > wait_for_completion(&comp); > if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK || > cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED) > - ret = SUCCESS; > + return SUCCESS; > > /* > * The spec guarantees that all requests related to the TMF have > @@ -613,33 +608,36 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) > * REQ_ATOM_COMPLETE has been set. > */ > virtscsi_poll_requests(vscsi); > - > -out: > - mempool_free(cmd, virtscsi_cmd_pool); > - return ret; > + return FAILED; > } > > static int virtscsi_device_reset(struct scsi_cmnd *sc) > { > + struct scsi_device *sdev = sc->device; > + struct scsi_cmnd *reset_sc; > struct virtio_scsi *vscsi = shost_priv(sc->device->host); > struct virtio_scsi_cmd *cmd; > + int rc; > > - sdev_printk(KERN_INFO, sc->device, "device reset\n"); > - cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); > - if (!cmd) > + sdev_printk(KERN_INFO, sdev, "device reset\n"); > + reset_sc = scsi_get_reserved_cmd(sdev, DMA_NONE); > + if (!reset_sc) > return FAILED; > - > + cmd = scsi_cmd_priv(reset_sc); > memset(cmd, 0, sizeof(*cmd)); > cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ > .type = VIRTIO_SCSI_T_TMF, > .subtype = cpu_to_virtio32(vscsi->vdev, > VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET), > .lun[0] = 1, > - .lun[1] = sc->device->id, > - .lun[2] = (sc->device->lun >> 8) | 0x40, > - .lun[3] = sc->device->lun & 0xff, > + .lun[1] = sdev->id, > + .lun[2] = (sdev->lun >> 8) | 0x40, > + .lun[3] = sdev->lun & 0xff, > }; > - return virtscsi_tmf(vscsi, cmd); > + rc = virtscsi_tmf(vscsi, cmd); > + scsi_put_reserved_cmd(reset_sc); > + > + return rc; > } > > static int virtscsi_device_alloc(struct scsi_device *sdevice) > @@ -679,25 +677,31 @@ static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth) > > static int virtscsi_abort(struct scsi_cmnd *sc) > { > - struct virtio_scsi *vscsi = shost_priv(sc->device->host); > + struct scsi_device *sdev = sc->device; > + struct scsi_cmnd *reset_sc; > + struct virtio_scsi *vscsi = shost_priv(sdev->host); > struct virtio_scsi_cmd *cmd; > + int rc; > > scmd_printk(KERN_INFO, sc, "abort\n"); > - cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); > - if (!cmd) > + reset_sc = scsi_get_reserved_cmd(sdev, DMA_NONE); > + if (!reset_sc) > return FAILED; > + cmd = scsi_cmd_priv(reset_sc); > > memset(cmd, 0, sizeof(*cmd)); > cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ > .type = VIRTIO_SCSI_T_TMF, > .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK, > .lun[0] = 1, > - .lun[1] = sc->device->id, > - .lun[2] = (sc->device->lun >> 8) | 0x40, > - .lun[3] = sc->device->lun & 0xff, > + .lun[1] = sdev->id, > + .lun[2] = (sdev->lun >> 8) | 0x40, > + .lun[3] = sdev->lun & 0xff, > .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc), > }; > - return virtscsi_tmf(vscsi, cmd); > + rc = virtscsi_tmf(vscsi, cmd); > + scsi_put_reserved_cmd(reset_sc); > + return rc; > } > > static int virtscsi_map_queues(struct Scsi_Host *shost) > @@ -865,6 +869,11 @@ static int virtscsi_probe(struct virtio_device *vdev) > goto virtscsi_init_failed; > > shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq); > + shost->can_queue -= VIRTIO_SCSI_RESERVED_CMDS; I guess it should have been '+=', right? Thanks, Ming
On Thu, Apr 30, 2020 at 03:18:29PM +0200, Hannes Reinecke wrote: > From: Hannes Reinecke <hare@suse.com> > > Set two commands aside for TMF, and use reserved commands to issue > TMFs. With that we can drop the TMF memory pool. > > Signed-off-by: Hannes Reinecke <hare@suse.com> > --- > drivers/scsi/virtio_scsi.c | 105 ++++++++++++++++++--------------------------- > 1 file changed, 41 insertions(+), 64 deletions(-) > > diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c > index 0e0910c5b942..26054c29d897 100644 > --- a/drivers/scsi/virtio_scsi.c > +++ b/drivers/scsi/virtio_scsi.c > @@ -35,10 +35,10 @@ > #define VIRTIO_SCSI_MEMPOOL_SZ 64 > #define VIRTIO_SCSI_EVENT_LEN 8 > #define VIRTIO_SCSI_VQ_BASE 2 > +#define VIRTIO_SCSI_RESERVED_CMDS 2 > > /* Command queue element */ > struct virtio_scsi_cmd { > - struct scsi_cmnd *sc; > struct completion *comp; > union { > struct virtio_scsi_cmd_req cmd; > @@ -86,9 +86,6 @@ struct virtio_scsi { > struct virtio_scsi_vq req_vqs[]; > }; > > -static struct kmem_cache *virtscsi_cmd_cache; > -static mempool_t *virtscsi_cmd_pool; > - > static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev) > { > return vdev->priv; > @@ -108,7 +105,7 @@ static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid) > static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) > { > struct virtio_scsi_cmd *cmd = buf; > - struct scsi_cmnd *sc = cmd->sc; > + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); > struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd; > > dev_dbg(&sc->device->sdev_gendev, > @@ -406,7 +403,7 @@ static int __virtscsi_add_cmd(struct virtqueue *vq, > struct virtio_scsi_cmd *cmd, > size_t req_size, size_t resp_size) > { > - struct scsi_cmnd *sc = cmd->sc; > + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); > struct scatterlist *sgs[6], req, resp; > struct sg_table *out, *in; > unsigned out_num = 0, in_num = 0; > @@ -557,8 +554,6 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, > dev_dbg(&sc->device->sdev_gendev, > "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); > > - cmd->sc = sc; > - > BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); > > #ifdef CONFIG_BLK_DEV_INTEGRITY > @@ -590,17 +585,17 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, > static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) > { > DECLARE_COMPLETION_ONSTACK(comp); > - int ret = FAILED; > > cmd->comp = ∁ > + > if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, > sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) virtscsi uses dedicated ->ctrl_vq to send TMF, and ->ctrl_vq isn't nothing to do with vqs(->vqs[]) for sending IO request. > - goto out; > + return FAILED; > > wait_for_completion(&comp); > if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK || > cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED) > - ret = SUCCESS; > + return SUCCESS; > > /* > * The spec guarantees that all requests related to the TMF have > @@ -613,33 +608,36 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) > * REQ_ATOM_COMPLETE has been set. > */ > virtscsi_poll_requests(vscsi); > - > -out: > - mempool_free(cmd, virtscsi_cmd_pool); > - return ret; > + return FAILED; > } > > static int virtscsi_device_reset(struct scsi_cmnd *sc) > { > + struct scsi_device *sdev = sc->device; > + struct scsi_cmnd *reset_sc; > struct virtio_scsi *vscsi = shost_priv(sc->device->host); > struct virtio_scsi_cmd *cmd; > + int rc; > > - sdev_printk(KERN_INFO, sc->device, "device reset\n"); > - cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); > - if (!cmd) > + sdev_printk(KERN_INFO, sdev, "device reset\n"); > + reset_sc = scsi_get_reserved_cmd(sdev, DMA_NONE); As commented above, virtio scsi doesn't use IO vqs to send TMF, so the above reserved command isn't necessary. There might be other example which do not require IO tag to send reset command. Thanks, Ming
On 5/4/20 11:25 AM, Ming Lei wrote: > On Thu, Apr 30, 2020 at 03:18:29PM +0200, Hannes Reinecke wrote: >> From: Hannes Reinecke <hare@suse.com> >> >> Set two commands aside for TMF, and use reserved commands to issue >> TMFs. With that we can drop the TMF memory pool. >> >> Signed-off-by: Hannes Reinecke <hare@suse.com> >> --- >> drivers/scsi/virtio_scsi.c | 105 ++++++++++++++++++--------------------------- >> 1 file changed, 41 insertions(+), 64 deletions(-) >> >> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c >> index 0e0910c5b942..26054c29d897 100644 >> --- a/drivers/scsi/virtio_scsi.c >> +++ b/drivers/scsi/virtio_scsi.c >> @@ -35,10 +35,10 @@ >> #define VIRTIO_SCSI_MEMPOOL_SZ 64 >> #define VIRTIO_SCSI_EVENT_LEN 8 >> #define VIRTIO_SCSI_VQ_BASE 2 >> +#define VIRTIO_SCSI_RESERVED_CMDS 2 >> >> /* Command queue element */ >> struct virtio_scsi_cmd { >> - struct scsi_cmnd *sc; >> struct completion *comp; >> union { >> struct virtio_scsi_cmd_req cmd; >> @@ -86,9 +86,6 @@ struct virtio_scsi { >> struct virtio_scsi_vq req_vqs[]; >> }; >> >> -static struct kmem_cache *virtscsi_cmd_cache; >> -static mempool_t *virtscsi_cmd_pool; >> - >> static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev) >> { >> return vdev->priv; >> @@ -108,7 +105,7 @@ static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid) >> static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) >> { >> struct virtio_scsi_cmd *cmd = buf; >> - struct scsi_cmnd *sc = cmd->sc; >> + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); >> struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd; >> >> dev_dbg(&sc->device->sdev_gendev, >> @@ -406,7 +403,7 @@ static int __virtscsi_add_cmd(struct virtqueue *vq, >> struct virtio_scsi_cmd *cmd, >> size_t req_size, size_t resp_size) >> { >> - struct scsi_cmnd *sc = cmd->sc; >> + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); >> struct scatterlist *sgs[6], req, resp; >> struct sg_table *out, *in; >> unsigned out_num = 0, in_num = 0; >> @@ -557,8 +554,6 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, >> dev_dbg(&sc->device->sdev_gendev, >> "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); >> >> - cmd->sc = sc; >> - >> BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); >> >> #ifdef CONFIG_BLK_DEV_INTEGRITY >> @@ -590,17 +585,17 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, >> static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) >> { >> DECLARE_COMPLETION_ONSTACK(comp); >> - int ret = FAILED; >> >> cmd->comp = ∁ >> + >> if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, >> sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) > > virtscsi uses dedicated ->ctrl_vq to send TMF, and ->ctrl_vq isn't > nothing to do with vqs(->vqs[]) for sending IO request. > Indeed, you are right. We should be handling this by adding a virtual LUN corresponding the the ctrl_vq and allocate commands from there. Will be updating for the next round. Cheers, Hannes
On Mon, May 04, 2020 at 12:21:57PM +0200, Hannes Reinecke wrote: > On 5/4/20 11:25 AM, Ming Lei wrote: > > On Thu, Apr 30, 2020 at 03:18:29PM +0200, Hannes Reinecke wrote: > > > From: Hannes Reinecke <hare@suse.com> > > > > > > Set two commands aside for TMF, and use reserved commands to issue > > > TMFs. With that we can drop the TMF memory pool. > > > > > > Signed-off-by: Hannes Reinecke <hare@suse.com> > > > --- > > > drivers/scsi/virtio_scsi.c | 105 ++++++++++++++++++--------------------------- > > > 1 file changed, 41 insertions(+), 64 deletions(-) > > > > > > diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c > > > index 0e0910c5b942..26054c29d897 100644 > > > --- a/drivers/scsi/virtio_scsi.c > > > +++ b/drivers/scsi/virtio_scsi.c > > > @@ -35,10 +35,10 @@ > > > #define VIRTIO_SCSI_MEMPOOL_SZ 64 > > > #define VIRTIO_SCSI_EVENT_LEN 8 > > > #define VIRTIO_SCSI_VQ_BASE 2 > > > +#define VIRTIO_SCSI_RESERVED_CMDS 2 > > > /* Command queue element */ > > > struct virtio_scsi_cmd { > > > - struct scsi_cmnd *sc; > > > struct completion *comp; > > > union { > > > struct virtio_scsi_cmd_req cmd; > > > @@ -86,9 +86,6 @@ struct virtio_scsi { > > > struct virtio_scsi_vq req_vqs[]; > > > }; > > > -static struct kmem_cache *virtscsi_cmd_cache; > > > -static mempool_t *virtscsi_cmd_pool; > > > - > > > static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev) > > > { > > > return vdev->priv; > > > @@ -108,7 +105,7 @@ static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid) > > > static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) > > > { > > > struct virtio_scsi_cmd *cmd = buf; > > > - struct scsi_cmnd *sc = cmd->sc; > > > + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); > > > struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd; > > > dev_dbg(&sc->device->sdev_gendev, > > > @@ -406,7 +403,7 @@ static int __virtscsi_add_cmd(struct virtqueue *vq, > > > struct virtio_scsi_cmd *cmd, > > > size_t req_size, size_t resp_size) > > > { > > > - struct scsi_cmnd *sc = cmd->sc; > > > + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); > > > struct scatterlist *sgs[6], req, resp; > > > struct sg_table *out, *in; > > > unsigned out_num = 0, in_num = 0; > > > @@ -557,8 +554,6 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, > > > dev_dbg(&sc->device->sdev_gendev, > > > "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); > > > - cmd->sc = sc; > > > - > > > BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); > > > #ifdef CONFIG_BLK_DEV_INTEGRITY > > > @@ -590,17 +585,17 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, > > > static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) > > > { > > > DECLARE_COMPLETION_ONSTACK(comp); > > > - int ret = FAILED; > > > cmd->comp = ∁ > > > + > > > if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, > > > sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) > > > > virtscsi uses dedicated ->ctrl_vq to send TMF, and ->ctrl_vq isn't > > nothing to do with vqs(->vqs[]) for sending IO request. > > > Indeed, you are right. > We should be handling this by adding a virtual LUN corresponding the the > ctrl_vq and allocate commands from there. I am not sure why we need this kind of change, and looks the current code just works fine. Thanks, Ming
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c index 0e0910c5b942..26054c29d897 100644 --- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -35,10 +35,10 @@ #define VIRTIO_SCSI_MEMPOOL_SZ 64 #define VIRTIO_SCSI_EVENT_LEN 8 #define VIRTIO_SCSI_VQ_BASE 2 +#define VIRTIO_SCSI_RESERVED_CMDS 2 /* Command queue element */ struct virtio_scsi_cmd { - struct scsi_cmnd *sc; struct completion *comp; union { struct virtio_scsi_cmd_req cmd; @@ -86,9 +86,6 @@ struct virtio_scsi { struct virtio_scsi_vq req_vqs[]; }; -static struct kmem_cache *virtscsi_cmd_cache; -static mempool_t *virtscsi_cmd_pool; - static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev) { return vdev->priv; @@ -108,7 +105,7 @@ static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid) static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) { struct virtio_scsi_cmd *cmd = buf; - struct scsi_cmnd *sc = cmd->sc; + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd; dev_dbg(&sc->device->sdev_gendev, @@ -406,7 +403,7 @@ static int __virtscsi_add_cmd(struct virtqueue *vq, struct virtio_scsi_cmd *cmd, size_t req_size, size_t resp_size) { - struct scsi_cmnd *sc = cmd->sc; + struct scsi_cmnd *sc = scsi_cmd_from_priv(cmd); struct scatterlist *sgs[6], req, resp; struct sg_table *out, *in; unsigned out_num = 0, in_num = 0; @@ -557,8 +554,6 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, dev_dbg(&sc->device->sdev_gendev, "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]); - cmd->sc = sc; - BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE); #ifdef CONFIG_BLK_DEV_INTEGRITY @@ -590,17 +585,17 @@ static int virtscsi_queuecommand(struct Scsi_Host *shost, static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) { DECLARE_COMPLETION_ONSTACK(comp); - int ret = FAILED; cmd->comp = ∁ + if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd, sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0) - goto out; + return FAILED; wait_for_completion(&comp); if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK || cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED) - ret = SUCCESS; + return SUCCESS; /* * The spec guarantees that all requests related to the TMF have @@ -613,33 +608,36 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) * REQ_ATOM_COMPLETE has been set. */ virtscsi_poll_requests(vscsi); - -out: - mempool_free(cmd, virtscsi_cmd_pool); - return ret; + return FAILED; } static int virtscsi_device_reset(struct scsi_cmnd *sc) { + struct scsi_device *sdev = sc->device; + struct scsi_cmnd *reset_sc; struct virtio_scsi *vscsi = shost_priv(sc->device->host); struct virtio_scsi_cmd *cmd; + int rc; - sdev_printk(KERN_INFO, sc->device, "device reset\n"); - cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); - if (!cmd) + sdev_printk(KERN_INFO, sdev, "device reset\n"); + reset_sc = scsi_get_reserved_cmd(sdev, DMA_NONE); + if (!reset_sc) return FAILED; - + cmd = scsi_cmd_priv(reset_sc); memset(cmd, 0, sizeof(*cmd)); cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ .type = VIRTIO_SCSI_T_TMF, .subtype = cpu_to_virtio32(vscsi->vdev, VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET), .lun[0] = 1, - .lun[1] = sc->device->id, - .lun[2] = (sc->device->lun >> 8) | 0x40, - .lun[3] = sc->device->lun & 0xff, + .lun[1] = sdev->id, + .lun[2] = (sdev->lun >> 8) | 0x40, + .lun[3] = sdev->lun & 0xff, }; - return virtscsi_tmf(vscsi, cmd); + rc = virtscsi_tmf(vscsi, cmd); + scsi_put_reserved_cmd(reset_sc); + + return rc; } static int virtscsi_device_alloc(struct scsi_device *sdevice) @@ -679,25 +677,31 @@ static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth) static int virtscsi_abort(struct scsi_cmnd *sc) { - struct virtio_scsi *vscsi = shost_priv(sc->device->host); + struct scsi_device *sdev = sc->device; + struct scsi_cmnd *reset_sc; + struct virtio_scsi *vscsi = shost_priv(sdev->host); struct virtio_scsi_cmd *cmd; + int rc; scmd_printk(KERN_INFO, sc, "abort\n"); - cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO); - if (!cmd) + reset_sc = scsi_get_reserved_cmd(sdev, DMA_NONE); + if (!reset_sc) return FAILED; + cmd = scsi_cmd_priv(reset_sc); memset(cmd, 0, sizeof(*cmd)); cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ .type = VIRTIO_SCSI_T_TMF, .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK, .lun[0] = 1, - .lun[1] = sc->device->id, - .lun[2] = (sc->device->lun >> 8) | 0x40, - .lun[3] = sc->device->lun & 0xff, + .lun[1] = sdev->id, + .lun[2] = (sdev->lun >> 8) | 0x40, + .lun[3] = sdev->lun & 0xff, .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc), }; - return virtscsi_tmf(vscsi, cmd); + rc = virtscsi_tmf(vscsi, cmd); + scsi_put_reserved_cmd(reset_sc); + return rc; } static int virtscsi_map_queues(struct Scsi_Host *shost) @@ -865,6 +869,11 @@ static int virtscsi_probe(struct virtio_device *vdev) goto virtscsi_init_failed; shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq); + shost->can_queue -= VIRTIO_SCSI_RESERVED_CMDS; + if (shost->can_queue <= 0) { + err = -ENOMEM; + goto scsi_add_host_failed; + } cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1; shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue); @@ -878,6 +887,7 @@ static int virtscsi_probe(struct virtio_device *vdev) shost->max_channel = 0; shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE; shost->nr_hw_queues = num_queues; + shost->nr_reserved_cmds = VIRTIO_SCSI_RESERVED_CMDS; #ifdef CONFIG_BLK_DEV_INTEGRITY if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) { @@ -979,45 +989,12 @@ static struct virtio_driver virtio_scsi_driver = { static int __init init(void) { - int ret = -ENOMEM; - - virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0); - if (!virtscsi_cmd_cache) { - pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n"); - goto error; - } - - - virtscsi_cmd_pool = - mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ, - virtscsi_cmd_cache); - if (!virtscsi_cmd_pool) { - pr_err("mempool_create() for virtscsi_cmd_pool failed\n"); - goto error; - } - ret = register_virtio_driver(&virtio_scsi_driver); - if (ret < 0) - goto error; - - return 0; - -error: - if (virtscsi_cmd_pool) { - mempool_destroy(virtscsi_cmd_pool); - virtscsi_cmd_pool = NULL; - } - if (virtscsi_cmd_cache) { - kmem_cache_destroy(virtscsi_cmd_cache); - virtscsi_cmd_cache = NULL; - } - return ret; + return register_virtio_driver(&virtio_scsi_driver); } static void __exit fini(void) { unregister_virtio_driver(&virtio_scsi_driver); - mempool_destroy(virtscsi_cmd_pool); - kmem_cache_destroy(virtscsi_cmd_cache); } module_init(init); module_exit(fini);