2 * Virtio SCSI HBA driver
4 * Copyright IBM Corp. 2010
5 * Copyright Red Hat, Inc. 2011
8 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
9 * Paolo Bonzini <pbonzini@redhat.com>
11 * This work is licensed under the terms of the GNU GPL, version 2 or later.
12 * See the COPYING file in the top-level directory.
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18 #include <linux/module.h>
19 #include <linux/slab.h>
20 #include <linux/mempool.h>
21 #include <linux/virtio.h>
22 #include <linux/virtio_ids.h>
23 #include <linux/virtio_config.h>
24 #include <linux/virtio_scsi.h>
25 #include <linux/cpu.h>
26 #include <linux/blkdev.h>
27 #include <scsi/scsi_host.h>
28 #include <scsi/scsi_device.h>
29 #include <scsi/scsi_cmnd.h>
31 #define VIRTIO_SCSI_MEMPOOL_SZ 64
32 #define VIRTIO_SCSI_EVENT_LEN 8
33 #define VIRTIO_SCSI_VQ_BASE 2
35 /* Command queue element */
36 struct virtio_scsi_cmd {
38 struct completion *comp;
40 struct virtio_scsi_cmd_req cmd;
41 struct virtio_scsi_cmd_req_pi cmd_pi;
42 struct virtio_scsi_ctrl_tmf_req tmf;
43 struct virtio_scsi_ctrl_an_req an;
46 struct virtio_scsi_cmd_resp cmd;
47 struct virtio_scsi_ctrl_tmf_resp tmf;
48 struct virtio_scsi_ctrl_an_resp an;
49 struct virtio_scsi_event evt;
51 } ____cacheline_aligned_in_smp;
53 struct virtio_scsi_event_node {
54 struct virtio_scsi *vscsi;
55 struct virtio_scsi_event event;
56 struct work_struct work;
59 struct virtio_scsi_vq {
67 * Per-target queue state.
69 * This struct holds the data needed by the queue steering policy. When a
70 * target is sent multiple requests, we need to drive them to the same queue so
71 * that FIFO processing order is kept. However, if a target was idle, we can
72 * choose a queue arbitrarily. In this case the queue is chosen according to
73 * the current VCPU, so the driver expects the number of request queues to be
74 * equal to the number of VCPUs. This makes it easy and fast to select the
75 * queue, and also lets the driver optimize the IRQ affinity for the virtqueues
76 * (each virtqueue's affinity is set to the CPU that "owns" the queue).
78 * tgt_lock is held to serialize reading and writing req_vq. Reading req_vq
79 * could be done locklessly, but we do not do it yet.
81 * Decrements of reqs are never concurrent with writes of req_vq: before the
82 * decrement reqs will be != 0; after the decrement the virtqueue completion
83 * routine will not use the req_vq so it can be changed by a new request.
84 * Thus they can happen outside the tgt_lock, provided of course we make reqs
87 struct virtio_scsi_target_state {
88 /* This spinlock never held at the same time as vq_lock. */
91 /* Count of outstanding requests. */
94 /* Currently active virtqueue for requests sent to this target. */
95 struct virtio_scsi_vq *req_vq;
98 /* Driver instance state */
100 struct virtio_device *vdev;
102 /* Get some buffers ready for event vq */
103 struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
107 /* If the affinity hint is set for virtqueues */
108 bool affinity_hint_set;
110 /* CPU hotplug notifier */
111 struct notifier_block nb;
113 struct virtio_scsi_vq ctrl_vq;
114 struct virtio_scsi_vq event_vq;
115 struct virtio_scsi_vq req_vqs[];
118 static struct kmem_cache *virtscsi_cmd_cache;
119 static mempool_t *virtscsi_cmd_pool;
121 static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
126 static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
131 if (!scsi_bidi_cmnd(sc)) {
132 scsi_set_resid(sc, resid);
136 scsi_in(sc)->resid = min(resid, scsi_in(sc)->length);
137 scsi_out(sc)->resid = resid - scsi_in(sc)->resid;
141 * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done
143 * Called with vq_lock held.
145 static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
147 struct virtio_scsi_cmd *cmd = buf;
148 struct scsi_cmnd *sc = cmd->sc;
149 struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
150 struct virtio_scsi_target_state *tgt =
151 scsi_target(sc->device)->hostdata;
153 dev_dbg(&sc->device->sdev_gendev,
154 "cmd %p response %u status %#02x sense_len %u\n",
155 sc, resp->response, resp->status, resp->sense_len);
157 sc->result = resp->status;
158 virtscsi_compute_resid(sc, resp->resid);
159 switch (resp->response) {
160 case VIRTIO_SCSI_S_OK:
161 set_host_byte(sc, DID_OK);
163 case VIRTIO_SCSI_S_OVERRUN:
164 set_host_byte(sc, DID_ERROR);
166 case VIRTIO_SCSI_S_ABORTED:
167 set_host_byte(sc, DID_ABORT);
169 case VIRTIO_SCSI_S_BAD_TARGET:
170 set_host_byte(sc, DID_BAD_TARGET);
172 case VIRTIO_SCSI_S_RESET:
173 set_host_byte(sc, DID_RESET);
175 case VIRTIO_SCSI_S_BUSY:
176 set_host_byte(sc, DID_BUS_BUSY);
178 case VIRTIO_SCSI_S_TRANSPORT_FAILURE:
179 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
181 case VIRTIO_SCSI_S_TARGET_FAILURE:
182 set_host_byte(sc, DID_TARGET_FAILURE);
184 case VIRTIO_SCSI_S_NEXUS_FAILURE:
185 set_host_byte(sc, DID_NEXUS_FAILURE);
188 scmd_printk(KERN_WARNING, sc, "Unknown response %d",
191 case VIRTIO_SCSI_S_FAILURE:
192 set_host_byte(sc, DID_ERROR);
196 WARN_ON(resp->sense_len > VIRTIO_SCSI_SENSE_SIZE);
197 if (sc->sense_buffer) {
198 memcpy(sc->sense_buffer, resp->sense,
199 min_t(u32, resp->sense_len, VIRTIO_SCSI_SENSE_SIZE));
201 set_driver_byte(sc, DRIVER_SENSE);
206 atomic_dec(&tgt->reqs);
209 static void virtscsi_vq_done(struct virtio_scsi *vscsi,
210 struct virtio_scsi_vq *virtscsi_vq,
211 void (*fn)(struct virtio_scsi *vscsi, void *buf))
216 struct virtqueue *vq = virtscsi_vq->vq;
218 spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
220 virtqueue_disable_cb(vq);
221 while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
224 if (unlikely(virtqueue_is_broken(vq)))
226 } while (!virtqueue_enable_cb(vq));
227 spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
230 static void virtscsi_req_done(struct virtqueue *vq)
232 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
233 struct virtio_scsi *vscsi = shost_priv(sh);
234 int index = vq->index - VIRTIO_SCSI_VQ_BASE;
235 struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
237 virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
240 static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
242 struct virtio_scsi_cmd *cmd = buf;
245 complete_all(cmd->comp);
248 static void virtscsi_ctrl_done(struct virtqueue *vq)
250 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
251 struct virtio_scsi *vscsi = shost_priv(sh);
253 virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
256 static int virtscsi_kick_event(struct virtio_scsi *vscsi,
257 struct virtio_scsi_event_node *event_node)
260 struct scatterlist sg;
263 sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
265 spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
267 err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
270 virtqueue_kick(vscsi->event_vq.vq);
272 spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
277 static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
281 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
282 vscsi->event_list[i].vscsi = vscsi;
283 virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
289 static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
293 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
294 cancel_work_sync(&vscsi->event_list[i].work);
297 static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
298 struct virtio_scsi_event *event)
300 struct scsi_device *sdev;
301 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
302 unsigned int target = event->lun[1];
303 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
305 switch (event->reason) {
306 case VIRTIO_SCSI_EVT_RESET_RESCAN:
307 scsi_add_device(shost, 0, target, lun);
309 case VIRTIO_SCSI_EVT_RESET_REMOVED:
310 sdev = scsi_device_lookup(shost, 0, target, lun);
312 scsi_remove_device(sdev);
313 scsi_device_put(sdev);
315 pr_err("SCSI device %d 0 %d %d not found\n",
316 shost->host_no, target, lun);
320 pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
324 static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
325 struct virtio_scsi_event *event)
327 struct scsi_device *sdev;
328 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
329 unsigned int target = event->lun[1];
330 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
331 u8 asc = event->reason & 255;
332 u8 ascq = event->reason >> 8;
334 sdev = scsi_device_lookup(shost, 0, target, lun);
336 pr_err("SCSI device %d 0 %d %d not found\n",
337 shost->host_no, target, lun);
341 /* Handle "Parameters changed", "Mode parameters changed", and
342 "Capacity data has changed". */
343 if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
344 scsi_rescan_device(&sdev->sdev_gendev);
346 scsi_device_put(sdev);
349 static void virtscsi_handle_event(struct work_struct *work)
351 struct virtio_scsi_event_node *event_node =
352 container_of(work, struct virtio_scsi_event_node, work);
353 struct virtio_scsi *vscsi = event_node->vscsi;
354 struct virtio_scsi_event *event = &event_node->event;
356 if (event->event & VIRTIO_SCSI_T_EVENTS_MISSED) {
357 event->event &= ~VIRTIO_SCSI_T_EVENTS_MISSED;
358 scsi_scan_host(virtio_scsi_host(vscsi->vdev));
361 switch (event->event) {
362 case VIRTIO_SCSI_T_NO_EVENT:
364 case VIRTIO_SCSI_T_TRANSPORT_RESET:
365 virtscsi_handle_transport_reset(vscsi, event);
367 case VIRTIO_SCSI_T_PARAM_CHANGE:
368 virtscsi_handle_param_change(vscsi, event);
371 pr_err("Unsupport virtio scsi event %x\n", event->event);
373 virtscsi_kick_event(vscsi, event_node);
376 static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
378 struct virtio_scsi_event_node *event_node = buf;
380 INIT_WORK(&event_node->work, virtscsi_handle_event);
381 schedule_work(&event_node->work);
384 static void virtscsi_event_done(struct virtqueue *vq)
386 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
387 struct virtio_scsi *vscsi = shost_priv(sh);
389 virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
393 * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue
394 * @vq : the struct virtqueue we're talking about
395 * @cmd : command structure
396 * @req_size : size of the request buffer
397 * @resp_size : size of the response buffer
399 static int virtscsi_add_cmd(struct virtqueue *vq,
400 struct virtio_scsi_cmd *cmd,
401 size_t req_size, size_t resp_size)
403 struct scsi_cmnd *sc = cmd->sc;
404 struct scatterlist *sgs[6], req, resp;
405 struct sg_table *out, *in;
406 unsigned out_num = 0, in_num = 0;
410 if (sc && sc->sc_data_direction != DMA_NONE) {
411 if (sc->sc_data_direction != DMA_FROM_DEVICE)
412 out = &scsi_out(sc)->table;
413 if (sc->sc_data_direction != DMA_TO_DEVICE)
414 in = &scsi_in(sc)->table;
417 /* Request header. */
418 sg_init_one(&req, &cmd->req, req_size);
419 sgs[out_num++] = &req;
421 /* Data-out buffer. */
423 /* Place WRITE protection SGLs before Data OUT payload */
424 if (scsi_prot_sg_count(sc))
425 sgs[out_num++] = scsi_prot_sglist(sc);
426 sgs[out_num++] = out->sgl;
429 /* Response header. */
430 sg_init_one(&resp, &cmd->resp, resp_size);
431 sgs[out_num + in_num++] = &resp;
435 /* Place READ protection SGLs before Data IN payload */
436 if (scsi_prot_sg_count(sc))
437 sgs[out_num + in_num++] = scsi_prot_sglist(sc);
438 sgs[out_num + in_num++] = in->sgl;
441 return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC);
444 static int virtscsi_kick_cmd(struct virtio_scsi_vq *vq,
445 struct virtio_scsi_cmd *cmd,
446 size_t req_size, size_t resp_size)
450 bool needs_kick = false;
452 spin_lock_irqsave(&vq->vq_lock, flags);
453 err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size);
455 needs_kick = virtqueue_kick_prepare(vq->vq);
457 spin_unlock_irqrestore(&vq->vq_lock, flags);
460 virtqueue_notify(vq->vq);
464 static void virtio_scsi_init_hdr(struct virtio_scsi_cmd_req *cmd,
465 struct scsi_cmnd *sc)
468 cmd->lun[1] = sc->device->id;
469 cmd->lun[2] = (sc->device->lun >> 8) | 0x40;
470 cmd->lun[3] = sc->device->lun & 0xff;
471 cmd->tag = (unsigned long)sc;
472 cmd->task_attr = VIRTIO_SCSI_S_SIMPLE;
477 static void virtio_scsi_init_hdr_pi(struct virtio_scsi_cmd_req_pi *cmd_pi,
478 struct scsi_cmnd *sc)
480 struct request *rq = sc->request;
481 struct blk_integrity *bi;
483 virtio_scsi_init_hdr((struct virtio_scsi_cmd_req *)cmd_pi, sc);
485 if (!rq || !scsi_prot_sg_count(sc))
488 bi = blk_get_integrity(rq->rq_disk);
490 if (sc->sc_data_direction == DMA_TO_DEVICE)
491 cmd_pi->pi_bytesout = blk_rq_sectors(rq) * bi->tuple_size;
492 else if (sc->sc_data_direction == DMA_FROM_DEVICE)
493 cmd_pi->pi_bytesin = blk_rq_sectors(rq) * bi->tuple_size;
496 static int virtscsi_queuecommand(struct virtio_scsi *vscsi,
497 struct virtio_scsi_vq *req_vq,
498 struct scsi_cmnd *sc)
500 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
501 struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc);
504 BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize);
506 /* TODO: check feature bit and fail if unsupported? */
507 BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL);
509 dev_dbg(&sc->device->sdev_gendev,
510 "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]);
512 memset(cmd, 0, sizeof(*cmd));
515 BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
517 if (virtio_has_feature(vscsi->vdev, VIRTIO_SCSI_F_T10_PI)) {
518 virtio_scsi_init_hdr_pi(&cmd->req.cmd_pi, sc);
519 memcpy(cmd->req.cmd_pi.cdb, sc->cmnd, sc->cmd_len);
520 req_size = sizeof(cmd->req.cmd_pi);
522 virtio_scsi_init_hdr(&cmd->req.cmd, sc);
523 memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
524 req_size = sizeof(cmd->req.cmd);
527 if (virtscsi_kick_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd)) != 0)
528 return SCSI_MLQUEUE_HOST_BUSY;
532 static int virtscsi_queuecommand_single(struct Scsi_Host *sh,
533 struct scsi_cmnd *sc)
535 struct virtio_scsi *vscsi = shost_priv(sh);
536 struct virtio_scsi_target_state *tgt =
537 scsi_target(sc->device)->hostdata;
539 atomic_inc(&tgt->reqs);
540 return virtscsi_queuecommand(vscsi, &vscsi->req_vqs[0], sc);
543 static struct virtio_scsi_vq *virtscsi_pick_vq(struct virtio_scsi *vscsi,
544 struct virtio_scsi_target_state *tgt)
546 struct virtio_scsi_vq *vq;
550 spin_lock_irqsave(&tgt->tgt_lock, flags);
552 if (atomic_inc_return(&tgt->reqs) > 1)
555 queue_num = smp_processor_id();
556 while (unlikely(queue_num >= vscsi->num_queues))
557 queue_num -= vscsi->num_queues;
559 tgt->req_vq = vq = &vscsi->req_vqs[queue_num];
562 spin_unlock_irqrestore(&tgt->tgt_lock, flags);
566 static int virtscsi_queuecommand_multi(struct Scsi_Host *sh,
567 struct scsi_cmnd *sc)
569 struct virtio_scsi *vscsi = shost_priv(sh);
570 struct virtio_scsi_target_state *tgt =
571 scsi_target(sc->device)->hostdata;
572 struct virtio_scsi_vq *req_vq = virtscsi_pick_vq(vscsi, tgt);
574 return virtscsi_queuecommand(vscsi, req_vq, sc);
577 static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
579 DECLARE_COMPLETION_ONSTACK(comp);
583 if (virtscsi_kick_cmd(&vscsi->ctrl_vq, cmd,
584 sizeof cmd->req.tmf, sizeof cmd->resp.tmf) < 0)
587 wait_for_completion(&comp);
588 if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
589 cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
593 mempool_free(cmd, virtscsi_cmd_pool);
597 static int virtscsi_device_reset(struct scsi_cmnd *sc)
599 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
600 struct virtio_scsi_cmd *cmd;
602 sdev_printk(KERN_INFO, sc->device, "device reset\n");
603 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
607 memset(cmd, 0, sizeof(*cmd));
609 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
610 .type = VIRTIO_SCSI_T_TMF,
611 .subtype = VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET,
613 .lun[1] = sc->device->id,
614 .lun[2] = (sc->device->lun >> 8) | 0x40,
615 .lun[3] = sc->device->lun & 0xff,
617 return virtscsi_tmf(vscsi, cmd);
620 static int virtscsi_abort(struct scsi_cmnd *sc)
622 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
623 struct virtio_scsi_cmd *cmd;
625 scmd_printk(KERN_INFO, sc, "abort\n");
626 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
630 memset(cmd, 0, sizeof(*cmd));
632 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
633 .type = VIRTIO_SCSI_T_TMF,
634 .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
636 .lun[1] = sc->device->id,
637 .lun[2] = (sc->device->lun >> 8) | 0x40,
638 .lun[3] = sc->device->lun & 0xff,
639 .tag = (unsigned long)sc,
641 return virtscsi_tmf(vscsi, cmd);
644 static int virtscsi_target_alloc(struct scsi_target *starget)
646 struct virtio_scsi_target_state *tgt =
647 kmalloc(sizeof(*tgt), GFP_KERNEL);
651 spin_lock_init(&tgt->tgt_lock);
652 atomic_set(&tgt->reqs, 0);
655 starget->hostdata = tgt;
659 static void virtscsi_target_destroy(struct scsi_target *starget)
661 struct virtio_scsi_target_state *tgt = starget->hostdata;
665 static struct scsi_host_template virtscsi_host_template_single = {
666 .module = THIS_MODULE,
667 .name = "Virtio SCSI HBA",
668 .proc_name = "virtio_scsi",
670 .cmd_size = sizeof(struct virtio_scsi_cmd),
671 .queuecommand = virtscsi_queuecommand_single,
672 .eh_abort_handler = virtscsi_abort,
673 .eh_device_reset_handler = virtscsi_device_reset,
676 .dma_boundary = UINT_MAX,
677 .use_clustering = ENABLE_CLUSTERING,
678 .target_alloc = virtscsi_target_alloc,
679 .target_destroy = virtscsi_target_destroy,
682 static struct scsi_host_template virtscsi_host_template_multi = {
683 .module = THIS_MODULE,
684 .name = "Virtio SCSI HBA",
685 .proc_name = "virtio_scsi",
687 .cmd_size = sizeof(struct virtio_scsi_cmd),
688 .queuecommand = virtscsi_queuecommand_multi,
689 .eh_abort_handler = virtscsi_abort,
690 .eh_device_reset_handler = virtscsi_device_reset,
693 .dma_boundary = UINT_MAX,
694 .use_clustering = ENABLE_CLUSTERING,
695 .target_alloc = virtscsi_target_alloc,
696 .target_destroy = virtscsi_target_destroy,
699 #define virtscsi_config_get(vdev, fld) \
701 typeof(((struct virtio_scsi_config *)0)->fld) __val; \
702 virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \
706 #define virtscsi_config_set(vdev, fld, val) \
708 typeof(((struct virtio_scsi_config *)0)->fld) __val = (val); \
709 virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \
712 static void __virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
717 /* In multiqueue mode, when the number of cpu is equal
718 * to the number of request queues, we let the qeueues
719 * to be private to one cpu by setting the affinity hint
720 * to eliminate the contention.
722 if ((vscsi->num_queues == 1 ||
723 vscsi->num_queues != num_online_cpus()) && affinity) {
724 if (vscsi->affinity_hint_set)
732 for_each_online_cpu(cpu) {
733 virtqueue_set_affinity(vscsi->req_vqs[i].vq, cpu);
737 vscsi->affinity_hint_set = true;
739 for (i = 0; i < vscsi->num_queues; i++) {
740 if (!vscsi->req_vqs[i].vq)
743 virtqueue_set_affinity(vscsi->req_vqs[i].vq, -1);
746 vscsi->affinity_hint_set = false;
750 static void virtscsi_set_affinity(struct virtio_scsi *vscsi, bool affinity)
753 __virtscsi_set_affinity(vscsi, affinity);
757 static int virtscsi_cpu_callback(struct notifier_block *nfb,
758 unsigned long action, void *hcpu)
760 struct virtio_scsi *vscsi = container_of(nfb, struct virtio_scsi, nb);
763 case CPU_ONLINE_FROZEN:
765 case CPU_DEAD_FROZEN:
766 __virtscsi_set_affinity(vscsi, true);
774 static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
775 struct virtqueue *vq)
777 spin_lock_init(&virtscsi_vq->vq_lock);
778 virtscsi_vq->vq = vq;
781 static void virtscsi_scan(struct virtio_device *vdev)
783 struct Scsi_Host *shost = (struct Scsi_Host *)vdev->priv;
785 scsi_scan_host(shost);
788 static void virtscsi_remove_vqs(struct virtio_device *vdev)
790 struct Scsi_Host *sh = virtio_scsi_host(vdev);
791 struct virtio_scsi *vscsi = shost_priv(sh);
793 virtscsi_set_affinity(vscsi, false);
795 /* Stop all the virtqueues. */
796 vdev->config->reset(vdev);
798 vdev->config->del_vqs(vdev);
801 static int virtscsi_init(struct virtio_device *vdev,
802 struct virtio_scsi *vscsi)
807 vq_callback_t **callbacks;
809 struct virtqueue **vqs;
811 num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE;
812 vqs = kmalloc(num_vqs * sizeof(struct virtqueue *), GFP_KERNEL);
813 callbacks = kmalloc(num_vqs * sizeof(vq_callback_t *), GFP_KERNEL);
814 names = kmalloc(num_vqs * sizeof(char *), GFP_KERNEL);
816 if (!callbacks || !vqs || !names) {
821 callbacks[0] = virtscsi_ctrl_done;
822 callbacks[1] = virtscsi_event_done;
823 names[0] = "control";
825 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) {
826 callbacks[i] = virtscsi_req_done;
827 names[i] = "request";
830 /* Discover virtqueues and write information to configuration. */
831 err = vdev->config->find_vqs(vdev, num_vqs, vqs, callbacks, names);
835 virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
836 virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
837 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
838 virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
841 virtscsi_set_affinity(vscsi, true);
843 virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
844 virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
846 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
847 virtscsi_kick_event_all(vscsi);
856 virtscsi_remove_vqs(vdev);
860 static int virtscsi_probe(struct virtio_device *vdev)
862 struct Scsi_Host *shost;
863 struct virtio_scsi *vscsi;
865 u32 sg_elems, num_targets;
868 struct scsi_host_template *hostt;
870 /* We need to know how many queues before we allocate. */
871 num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
873 num_targets = virtscsi_config_get(vdev, max_target) + 1;
876 hostt = &virtscsi_host_template_single;
878 hostt = &virtscsi_host_template_multi;
880 shost = scsi_host_alloc(hostt,
881 sizeof(*vscsi) + sizeof(vscsi->req_vqs[0]) * num_queues);
885 sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
886 shost->sg_tablesize = sg_elems;
887 vscsi = shost_priv(shost);
889 vscsi->num_queues = num_queues;
892 err = virtscsi_init(vdev, vscsi);
894 goto virtscsi_init_failed;
896 vscsi->nb.notifier_call = &virtscsi_cpu_callback;
897 err = register_hotcpu_notifier(&vscsi->nb);
899 pr_err("registering cpu notifier failed\n");
900 goto scsi_add_host_failed;
903 cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
904 shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
905 shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
907 /* LUNs > 256 are reported with format 1, so they go in the range
910 shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
911 shost->max_id = num_targets;
912 shost->max_channel = 0;
913 shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
915 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) {
916 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
917 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
918 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
920 scsi_host_set_prot(shost, host_prot);
921 scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC);
924 err = scsi_add_host(shost, &vdev->dev);
926 goto scsi_add_host_failed;
928 * scsi_scan_host() happens in virtscsi_scan() via virtio_driver->scan()
929 * after VIRTIO_CONFIG_S_DRIVER_OK has been set..
933 scsi_add_host_failed:
934 vdev->config->del_vqs(vdev);
935 virtscsi_init_failed:
936 scsi_host_put(shost);
940 static void virtscsi_remove(struct virtio_device *vdev)
942 struct Scsi_Host *shost = virtio_scsi_host(vdev);
943 struct virtio_scsi *vscsi = shost_priv(shost);
945 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
946 virtscsi_cancel_event_work(vscsi);
948 scsi_remove_host(shost);
950 unregister_hotcpu_notifier(&vscsi->nb);
952 virtscsi_remove_vqs(vdev);
953 scsi_host_put(shost);
956 #ifdef CONFIG_PM_SLEEP
957 static int virtscsi_freeze(struct virtio_device *vdev)
959 struct Scsi_Host *sh = virtio_scsi_host(vdev);
960 struct virtio_scsi *vscsi = shost_priv(sh);
962 unregister_hotcpu_notifier(&vscsi->nb);
963 virtscsi_remove_vqs(vdev);
967 static int virtscsi_restore(struct virtio_device *vdev)
969 struct Scsi_Host *sh = virtio_scsi_host(vdev);
970 struct virtio_scsi *vscsi = shost_priv(sh);
973 err = virtscsi_init(vdev, vscsi);
977 err = register_hotcpu_notifier(&vscsi->nb);
979 vdev->config->del_vqs(vdev);
985 static struct virtio_device_id id_table[] = {
986 { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID },
990 static unsigned int features[] = {
991 VIRTIO_SCSI_F_HOTPLUG,
992 VIRTIO_SCSI_F_CHANGE,
993 VIRTIO_SCSI_F_T10_PI,
996 static struct virtio_driver virtio_scsi_driver = {
997 .feature_table = features,
998 .feature_table_size = ARRAY_SIZE(features),
999 .driver.name = KBUILD_MODNAME,
1000 .driver.owner = THIS_MODULE,
1001 .id_table = id_table,
1002 .probe = virtscsi_probe,
1003 .scan = virtscsi_scan,
1004 #ifdef CONFIG_PM_SLEEP
1005 .freeze = virtscsi_freeze,
1006 .restore = virtscsi_restore,
1008 .remove = virtscsi_remove,
1011 static int __init init(void)
1015 virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
1016 if (!virtscsi_cmd_cache) {
1017 pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
1023 mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
1024 virtscsi_cmd_cache);
1025 if (!virtscsi_cmd_pool) {
1026 pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
1029 ret = register_virtio_driver(&virtio_scsi_driver);
1036 if (virtscsi_cmd_pool) {
1037 mempool_destroy(virtscsi_cmd_pool);
1038 virtscsi_cmd_pool = NULL;
1040 if (virtscsi_cmd_cache) {
1041 kmem_cache_destroy(virtscsi_cmd_cache);
1042 virtscsi_cmd_cache = NULL;
1047 static void __exit fini(void)
1049 unregister_virtio_driver(&virtio_scsi_driver);
1050 mempool_destroy(virtscsi_cmd_pool);
1051 kmem_cache_destroy(virtscsi_cmd_cache);
1056 MODULE_DEVICE_TABLE(virtio, id_table);
1057 MODULE_DESCRIPTION("Virtio SCSI HBA driver");
1058 MODULE_LICENSE("GPL");