1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Virtio SCSI HBA driver
5 * Copyright IBM Corp. 2010
6 * Copyright Red Hat, Inc. 2011
9 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
10 * Paolo Bonzini <pbonzini@redhat.com>
13 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <linux/mempool.h>
18 #include <linux/interrupt.h>
19 #include <linux/virtio.h>
20 #include <linux/virtio_ids.h>
21 #include <linux/virtio_config.h>
22 #include <linux/virtio_scsi.h>
23 #include <linux/cpu.h>
24 #include <linux/blkdev.h>
25 #include <linux/blk-integrity.h>
26 #include <scsi/scsi_host.h>
27 #include <scsi/scsi_device.h>
28 #include <scsi/scsi_cmnd.h>
29 #include <scsi/scsi_tcq.h>
30 #include <scsi/scsi_devinfo.h>
31 #include <linux/seqlock.h>
32 #include <linux/blk-mq-virtio.h>
36 #define VIRTIO_SCSI_MEMPOOL_SZ 64
37 #define VIRTIO_SCSI_EVENT_LEN 8
38 #define VIRTIO_SCSI_VQ_BASE 2
40 static unsigned int virtscsi_poll_queues;
41 module_param(virtscsi_poll_queues, uint, 0644);
42 MODULE_PARM_DESC(virtscsi_poll_queues,
43 "The number of dedicated virtqueues for polling I/O");
45 /* Command queue element */
46 struct virtio_scsi_cmd {
48 struct completion *comp;
50 struct virtio_scsi_cmd_req cmd;
51 struct virtio_scsi_cmd_req_pi cmd_pi;
52 struct virtio_scsi_ctrl_tmf_req tmf;
53 struct virtio_scsi_ctrl_an_req an;
56 struct virtio_scsi_cmd_resp cmd;
57 struct virtio_scsi_ctrl_tmf_resp tmf;
58 struct virtio_scsi_ctrl_an_resp an;
59 struct virtio_scsi_event evt;
61 } ____cacheline_aligned_in_smp;
63 struct virtio_scsi_event_node {
64 struct virtio_scsi *vscsi;
65 struct virtio_scsi_event event;
66 struct work_struct work;
69 struct virtio_scsi_vq {
76 /* Driver instance state */
78 struct virtio_device *vdev;
80 /* Get some buffers ready for event vq */
81 struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
84 int io_queues[HCTX_MAX_TYPES];
86 struct hlist_node node;
88 /* Protected by event_vq lock */
91 struct virtio_scsi_vq ctrl_vq;
92 struct virtio_scsi_vq event_vq;
93 struct virtio_scsi_vq req_vqs[];
96 static struct kmem_cache *virtscsi_cmd_cache;
97 static mempool_t *virtscsi_cmd_pool;
99 static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
104 static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
107 scsi_set_resid(sc, min(resid, scsi_bufflen(sc)));
111 * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done
113 * Called with vq_lock held.
115 static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
117 struct virtio_scsi_cmd *cmd = buf;
118 struct scsi_cmnd *sc = cmd->sc;
119 struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
121 dev_dbg(&sc->device->sdev_gendev,
122 "cmd %p response %u status %#02x sense_len %u\n",
123 sc, resp->response, resp->status, resp->sense_len);
125 sc->result = resp->status;
126 virtscsi_compute_resid(sc, virtio32_to_cpu(vscsi->vdev, resp->resid));
127 switch (resp->response) {
128 case VIRTIO_SCSI_S_OK:
129 set_host_byte(sc, DID_OK);
131 case VIRTIO_SCSI_S_OVERRUN:
132 set_host_byte(sc, DID_ERROR);
134 case VIRTIO_SCSI_S_ABORTED:
135 set_host_byte(sc, DID_ABORT);
137 case VIRTIO_SCSI_S_BAD_TARGET:
138 set_host_byte(sc, DID_BAD_TARGET);
140 case VIRTIO_SCSI_S_RESET:
141 set_host_byte(sc, DID_RESET);
143 case VIRTIO_SCSI_S_BUSY:
144 set_host_byte(sc, DID_BUS_BUSY);
146 case VIRTIO_SCSI_S_TRANSPORT_FAILURE:
147 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
149 case VIRTIO_SCSI_S_TARGET_FAILURE:
150 set_host_byte(sc, DID_BAD_TARGET);
152 case VIRTIO_SCSI_S_NEXUS_FAILURE:
153 set_status_byte(sc, SAM_STAT_RESERVATION_CONFLICT);
156 scmd_printk(KERN_WARNING, sc, "Unknown response %d",
159 case VIRTIO_SCSI_S_FAILURE:
160 set_host_byte(sc, DID_ERROR);
164 WARN_ON(virtio32_to_cpu(vscsi->vdev, resp->sense_len) >
165 VIRTIO_SCSI_SENSE_SIZE);
166 if (resp->sense_len) {
167 memcpy(sc->sense_buffer, resp->sense,
169 virtio32_to_cpu(vscsi->vdev, resp->sense_len),
170 VIRTIO_SCSI_SENSE_SIZE));
176 static void virtscsi_vq_done(struct virtio_scsi *vscsi,
177 struct virtio_scsi_vq *virtscsi_vq,
178 void (*fn)(struct virtio_scsi *vscsi, void *buf))
183 struct virtqueue *vq = virtscsi_vq->vq;
185 spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
187 virtqueue_disable_cb(vq);
188 while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
191 } while (!virtqueue_enable_cb(vq));
192 spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
195 static void virtscsi_req_done(struct virtqueue *vq)
197 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
198 struct virtio_scsi *vscsi = shost_priv(sh);
199 int index = vq->index - VIRTIO_SCSI_VQ_BASE;
200 struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
202 virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
205 static void virtscsi_poll_requests(struct virtio_scsi *vscsi)
209 num_vqs = vscsi->num_queues;
210 for (i = 0; i < num_vqs; i++)
211 virtscsi_vq_done(vscsi, &vscsi->req_vqs[i],
212 virtscsi_complete_cmd);
215 static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
217 struct virtio_scsi_cmd *cmd = buf;
223 static void virtscsi_ctrl_done(struct virtqueue *vq)
225 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
226 struct virtio_scsi *vscsi = shost_priv(sh);
228 virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
231 static void virtscsi_handle_event(struct work_struct *work);
233 static int virtscsi_kick_event(struct virtio_scsi *vscsi,
234 struct virtio_scsi_event_node *event_node)
237 struct scatterlist sg;
240 INIT_WORK(&event_node->work, virtscsi_handle_event);
241 sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
243 spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
245 err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
248 virtqueue_kick(vscsi->event_vq.vq);
250 spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
255 static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
259 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
260 vscsi->event_list[i].vscsi = vscsi;
261 virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
267 static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
271 /* Stop scheduling work before calling cancel_work_sync. */
272 spin_lock_irq(&vscsi->event_vq.vq_lock);
273 vscsi->stop_events = true;
274 spin_unlock_irq(&vscsi->event_vq.vq_lock);
276 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
277 cancel_work_sync(&vscsi->event_list[i].work);
280 static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
281 struct virtio_scsi_event *event)
283 struct scsi_device *sdev;
284 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
285 unsigned int target = event->lun[1];
286 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
288 switch (virtio32_to_cpu(vscsi->vdev, event->reason)) {
289 case VIRTIO_SCSI_EVT_RESET_RESCAN:
291 scsi_scan_target(&shost->shost_gendev, 0, target,
292 SCAN_WILD_CARD, SCSI_SCAN_INITIAL);
294 scsi_add_device(shost, 0, target, lun);
297 case VIRTIO_SCSI_EVT_RESET_REMOVED:
298 sdev = scsi_device_lookup(shost, 0, target, lun);
300 scsi_remove_device(sdev);
301 scsi_device_put(sdev);
303 pr_err("SCSI device %d 0 %d %d not found\n",
304 shost->host_no, target, lun);
308 pr_info("Unsupported virtio scsi event reason %x\n", event->reason);
312 static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
313 struct virtio_scsi_event *event)
315 struct scsi_device *sdev;
316 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
317 unsigned int target = event->lun[1];
318 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
319 u8 asc = virtio32_to_cpu(vscsi->vdev, event->reason) & 255;
320 u8 ascq = virtio32_to_cpu(vscsi->vdev, event->reason) >> 8;
322 sdev = scsi_device_lookup(shost, 0, target, lun);
324 pr_err("SCSI device %d 0 %d %d not found\n",
325 shost->host_no, target, lun);
329 /* Handle "Parameters changed", "Mode parameters changed", and
330 "Capacity data has changed". */
331 if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
332 scsi_rescan_device(sdev);
334 scsi_device_put(sdev);
337 static int virtscsi_rescan_hotunplug(struct virtio_scsi *vscsi)
339 struct scsi_device *sdev;
340 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
341 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
342 int result, inquiry_len, inq_result_len = 256;
343 char *inq_result = kmalloc(inq_result_len, GFP_KERNEL);
348 shost_for_each_device(sdev, shost) {
349 inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
351 memset(scsi_cmd, 0, sizeof(scsi_cmd));
352 scsi_cmd[0] = INQUIRY;
353 scsi_cmd[4] = (unsigned char) inquiry_len;
355 memset(inq_result, 0, inq_result_len);
357 result = scsi_execute_cmd(sdev, scsi_cmd, REQ_OP_DRV_IN,
358 inq_result, inquiry_len,
359 SD_TIMEOUT, SD_MAX_RETRIES, NULL);
361 if (result == 0 && inq_result[0] >> 5) {
362 /* PQ indicates the LUN is not attached */
363 scsi_remove_device(sdev);
364 } else if (result > 0 && host_byte(result) == DID_BAD_TARGET) {
366 * If all LUNs of a virtio-scsi device are unplugged
367 * it will respond with BAD TARGET on any INQUIRY
369 * Remove the device in this case as well.
371 scsi_remove_device(sdev);
379 static void virtscsi_handle_event(struct work_struct *work)
381 struct virtio_scsi_event_node *event_node =
382 container_of(work, struct virtio_scsi_event_node, work);
383 struct virtio_scsi *vscsi = event_node->vscsi;
384 struct virtio_scsi_event *event = &event_node->event;
387 cpu_to_virtio32(vscsi->vdev, VIRTIO_SCSI_T_EVENTS_MISSED)) {
390 event->event &= ~cpu_to_virtio32(vscsi->vdev,
391 VIRTIO_SCSI_T_EVENTS_MISSED);
392 ret = virtscsi_rescan_hotunplug(vscsi);
395 scsi_scan_host(virtio_scsi_host(vscsi->vdev));
398 switch (virtio32_to_cpu(vscsi->vdev, event->event)) {
399 case VIRTIO_SCSI_T_NO_EVENT:
401 case VIRTIO_SCSI_T_TRANSPORT_RESET:
402 virtscsi_handle_transport_reset(vscsi, event);
404 case VIRTIO_SCSI_T_PARAM_CHANGE:
405 virtscsi_handle_param_change(vscsi, event);
408 pr_err("Unsupported virtio scsi event %x\n", event->event);
410 virtscsi_kick_event(vscsi, event_node);
413 static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
415 struct virtio_scsi_event_node *event_node = buf;
417 if (!vscsi->stop_events)
418 queue_work(system_freezable_wq, &event_node->work);
421 static void virtscsi_event_done(struct virtqueue *vq)
423 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
424 struct virtio_scsi *vscsi = shost_priv(sh);
426 virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
429 static int __virtscsi_add_cmd(struct virtqueue *vq,
430 struct virtio_scsi_cmd *cmd,
431 size_t req_size, size_t resp_size)
433 struct scsi_cmnd *sc = cmd->sc;
434 struct scatterlist *sgs[6], req, resp;
435 struct sg_table *out, *in;
436 unsigned out_num = 0, in_num = 0;
440 if (sc && sc->sc_data_direction != DMA_NONE) {
441 if (sc->sc_data_direction != DMA_FROM_DEVICE)
442 out = &sc->sdb.table;
443 if (sc->sc_data_direction != DMA_TO_DEVICE)
447 /* Request header. */
448 sg_init_one(&req, &cmd->req, req_size);
449 sgs[out_num++] = &req;
451 /* Data-out buffer. */
453 /* Place WRITE protection SGLs before Data OUT payload */
454 if (scsi_prot_sg_count(sc))
455 sgs[out_num++] = scsi_prot_sglist(sc);
456 sgs[out_num++] = out->sgl;
459 /* Response header. */
460 sg_init_one(&resp, &cmd->resp, resp_size);
461 sgs[out_num + in_num++] = &resp;
465 /* Place READ protection SGLs before Data IN payload */
466 if (scsi_prot_sg_count(sc))
467 sgs[out_num + in_num++] = scsi_prot_sglist(sc);
468 sgs[out_num + in_num++] = in->sgl;
471 return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC);
474 static void virtscsi_kick_vq(struct virtio_scsi_vq *vq)
479 spin_lock_irqsave(&vq->vq_lock, flags);
480 needs_kick = virtqueue_kick_prepare(vq->vq);
481 spin_unlock_irqrestore(&vq->vq_lock, flags);
484 virtqueue_notify(vq->vq);
488 * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue, optionally kick it
489 * @vq : the struct virtqueue we're talking about
490 * @cmd : command structure
491 * @req_size : size of the request buffer
492 * @resp_size : size of the response buffer
493 * @kick : whether to kick the virtqueue immediately
495 static int virtscsi_add_cmd(struct virtio_scsi_vq *vq,
496 struct virtio_scsi_cmd *cmd,
497 size_t req_size, size_t resp_size,
502 bool needs_kick = false;
504 spin_lock_irqsave(&vq->vq_lock, flags);
505 err = __virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size);
507 needs_kick = virtqueue_kick_prepare(vq->vq);
509 spin_unlock_irqrestore(&vq->vq_lock, flags);
512 virtqueue_notify(vq->vq);
516 static void virtio_scsi_init_hdr(struct virtio_device *vdev,
517 struct virtio_scsi_cmd_req *cmd,
518 struct scsi_cmnd *sc)
521 cmd->lun[1] = sc->device->id;
522 cmd->lun[2] = (sc->device->lun >> 8) | 0x40;
523 cmd->lun[3] = sc->device->lun & 0xff;
524 cmd->tag = cpu_to_virtio64(vdev, (unsigned long)sc);
525 cmd->task_attr = VIRTIO_SCSI_S_SIMPLE;
530 #ifdef CONFIG_BLK_DEV_INTEGRITY
531 static void virtio_scsi_init_hdr_pi(struct virtio_device *vdev,
532 struct virtio_scsi_cmd_req_pi *cmd_pi,
533 struct scsi_cmnd *sc)
535 struct request *rq = scsi_cmd_to_rq(sc);
536 struct blk_integrity *bi;
538 virtio_scsi_init_hdr(vdev, (struct virtio_scsi_cmd_req *)cmd_pi, sc);
540 if (!rq || !scsi_prot_sg_count(sc))
543 bi = blk_get_integrity(rq->q->disk);
545 if (sc->sc_data_direction == DMA_TO_DEVICE)
546 cmd_pi->pi_bytesout = cpu_to_virtio32(vdev,
547 bio_integrity_bytes(bi,
548 blk_rq_sectors(rq)));
549 else if (sc->sc_data_direction == DMA_FROM_DEVICE)
550 cmd_pi->pi_bytesin = cpu_to_virtio32(vdev,
551 bio_integrity_bytes(bi,
552 blk_rq_sectors(rq)));
556 static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi,
557 struct scsi_cmnd *sc)
559 u32 tag = blk_mq_unique_tag(scsi_cmd_to_rq(sc));
560 u16 hwq = blk_mq_unique_tag_to_hwq(tag);
562 return &vscsi->req_vqs[hwq];
565 static int virtscsi_queuecommand(struct Scsi_Host *shost,
566 struct scsi_cmnd *sc)
568 struct virtio_scsi *vscsi = shost_priv(shost);
569 struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc);
570 struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc);
576 BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize);
578 /* TODO: check feature bit and fail if unsupported? */
579 BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL);
581 dev_dbg(&sc->device->sdev_gendev,
582 "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]);
586 BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
588 #ifdef CONFIG_BLK_DEV_INTEGRITY
589 if (virtio_has_feature(vscsi->vdev, VIRTIO_SCSI_F_T10_PI)) {
590 virtio_scsi_init_hdr_pi(vscsi->vdev, &cmd->req.cmd_pi, sc);
591 memcpy(cmd->req.cmd_pi.cdb, sc->cmnd, sc->cmd_len);
592 req_size = sizeof(cmd->req.cmd_pi);
596 virtio_scsi_init_hdr(vscsi->vdev, &cmd->req.cmd, sc);
597 memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
598 req_size = sizeof(cmd->req.cmd);
601 kick = (sc->flags & SCMD_LAST) != 0;
602 ret = virtscsi_add_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd), kick);
604 cmd->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
605 spin_lock_irqsave(&req_vq->vq_lock, flags);
606 virtscsi_complete_cmd(vscsi, cmd);
607 spin_unlock_irqrestore(&req_vq->vq_lock, flags);
608 } else if (ret != 0) {
609 return SCSI_MLQUEUE_HOST_BUSY;
614 static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
616 DECLARE_COMPLETION_ONSTACK(comp);
620 if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd,
621 sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0)
624 wait_for_completion(&comp);
625 if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
626 cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
630 * The spec guarantees that all requests related to the TMF have
631 * been completed, but the callback might not have run yet if
632 * we're using independent interrupts (e.g. MSI). Poll the
635 * In the abort case, scsi_done() will do nothing, because the
636 * command timed out and hence SCMD_STATE_COMPLETE has been set.
638 virtscsi_poll_requests(vscsi);
641 mempool_free(cmd, virtscsi_cmd_pool);
645 static int virtscsi_device_reset(struct scsi_cmnd *sc)
647 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
648 struct virtio_scsi_cmd *cmd;
650 sdev_printk(KERN_INFO, sc->device, "device reset\n");
651 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
655 memset(cmd, 0, sizeof(*cmd));
656 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
657 .type = VIRTIO_SCSI_T_TMF,
658 .subtype = cpu_to_virtio32(vscsi->vdev,
659 VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET),
661 .lun[1] = sc->device->id,
662 .lun[2] = (sc->device->lun >> 8) | 0x40,
663 .lun[3] = sc->device->lun & 0xff,
665 return virtscsi_tmf(vscsi, cmd);
668 static int virtscsi_device_alloc(struct scsi_device *sdevice)
671 * Passed through SCSI targets (e.g. with qemu's 'scsi-block')
672 * may have transfer limits which come from the host SCSI
673 * controller or something on the host side other than the
676 * To make this work properly, the hypervisor can adjust the
677 * target's VPD information to advertise these limits. But
678 * for that to work, the guest has to look at the VPD pages,
679 * which we won't do by default if it is an SPC-2 device, even
680 * if it does actually support it.
682 * So, set the blist to always try to read the VPD pages.
684 sdevice->sdev_bflags = BLIST_TRY_VPD_PAGES;
691 * virtscsi_change_queue_depth() - Change a virtscsi target's queue depth
692 * @sdev: Virtscsi target whose queue depth to change
693 * @qdepth: New queue depth
695 static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
697 struct Scsi_Host *shost = sdev->host;
698 int max_depth = shost->cmd_per_lun;
700 return scsi_change_queue_depth(sdev, min(max_depth, qdepth));
703 static int virtscsi_abort(struct scsi_cmnd *sc)
705 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
706 struct virtio_scsi_cmd *cmd;
708 scmd_printk(KERN_INFO, sc, "abort\n");
709 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
713 memset(cmd, 0, sizeof(*cmd));
714 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
715 .type = VIRTIO_SCSI_T_TMF,
716 .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
718 .lun[1] = sc->device->id,
719 .lun[2] = (sc->device->lun >> 8) | 0x40,
720 .lun[3] = sc->device->lun & 0xff,
721 .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc),
723 return virtscsi_tmf(vscsi, cmd);
726 static void virtscsi_map_queues(struct Scsi_Host *shost)
728 struct virtio_scsi *vscsi = shost_priv(shost);
731 for (i = 0, qoff = 0; i < shost->nr_maps; i++) {
732 struct blk_mq_queue_map *map = &shost->tag_set.map[i];
734 map->nr_queues = vscsi->io_queues[i];
735 map->queue_offset = qoff;
736 qoff += map->nr_queues;
738 if (map->nr_queues == 0)
742 * Regular queues have interrupts and hence CPU affinity is
743 * defined by the core virtio code, but polling queues have
744 * no interrupts so we let the block layer assign CPU affinity.
746 if (i == HCTX_TYPE_POLL)
747 blk_mq_map_queues(map);
749 blk_mq_virtio_map_queues(map, vscsi->vdev, 2);
753 static int virtscsi_mq_poll(struct Scsi_Host *shost, unsigned int queue_num)
755 struct virtio_scsi *vscsi = shost_priv(shost);
756 struct virtio_scsi_vq *virtscsi_vq = &vscsi->req_vqs[queue_num];
762 spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
764 while ((buf = virtqueue_get_buf(virtscsi_vq->vq, &len)) != NULL) {
765 virtscsi_complete_cmd(vscsi, buf);
769 spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
774 static void virtscsi_commit_rqs(struct Scsi_Host *shost, u16 hwq)
776 struct virtio_scsi *vscsi = shost_priv(shost);
778 virtscsi_kick_vq(&vscsi->req_vqs[hwq]);
782 * The host guarantees to respond to each command, although I/O
783 * latencies might be higher than on bare metal. Reset the timer
784 * unconditionally to give the host a chance to perform EH.
786 static enum scsi_timeout_action virtscsi_eh_timed_out(struct scsi_cmnd *scmnd)
788 return SCSI_EH_RESET_TIMER;
791 static const struct scsi_host_template virtscsi_host_template = {
792 .module = THIS_MODULE,
793 .name = "Virtio SCSI HBA",
794 .proc_name = "virtio_scsi",
796 .cmd_size = sizeof(struct virtio_scsi_cmd),
797 .queuecommand = virtscsi_queuecommand,
798 .mq_poll = virtscsi_mq_poll,
799 .commit_rqs = virtscsi_commit_rqs,
800 .change_queue_depth = virtscsi_change_queue_depth,
801 .eh_abort_handler = virtscsi_abort,
802 .eh_device_reset_handler = virtscsi_device_reset,
803 .eh_timed_out = virtscsi_eh_timed_out,
804 .slave_alloc = virtscsi_device_alloc,
806 .dma_boundary = UINT_MAX,
807 .map_queues = virtscsi_map_queues,
808 .track_queue_depth = 1,
811 #define virtscsi_config_get(vdev, fld) \
813 __virtio_native_type(struct virtio_scsi_config, fld) __val; \
814 virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \
818 #define virtscsi_config_set(vdev, fld, val) \
820 __virtio_native_type(struct virtio_scsi_config, fld) __val = (val); \
821 virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \
824 static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
825 struct virtqueue *vq)
827 spin_lock_init(&virtscsi_vq->vq_lock);
828 virtscsi_vq->vq = vq;
831 static void virtscsi_remove_vqs(struct virtio_device *vdev)
833 /* Stop all the virtqueues. */
834 virtio_reset_device(vdev);
835 vdev->config->del_vqs(vdev);
838 static int virtscsi_init(struct virtio_device *vdev,
839 struct virtio_scsi *vscsi)
843 u32 num_vqs, num_poll_vqs, num_req_vqs;
844 vq_callback_t **callbacks;
846 struct virtqueue **vqs;
847 struct irq_affinity desc = { .pre_vectors = 2 };
849 num_req_vqs = vscsi->num_queues;
850 num_vqs = num_req_vqs + VIRTIO_SCSI_VQ_BASE;
851 vqs = kmalloc_array(num_vqs, sizeof(struct virtqueue *), GFP_KERNEL);
852 callbacks = kmalloc_array(num_vqs, sizeof(vq_callback_t *),
854 names = kmalloc_array(num_vqs, sizeof(char *), GFP_KERNEL);
856 if (!callbacks || !vqs || !names) {
861 num_poll_vqs = min_t(unsigned int, virtscsi_poll_queues,
863 vscsi->io_queues[HCTX_TYPE_DEFAULT] = num_req_vqs - num_poll_vqs;
864 vscsi->io_queues[HCTX_TYPE_READ] = 0;
865 vscsi->io_queues[HCTX_TYPE_POLL] = num_poll_vqs;
867 dev_info(&vdev->dev, "%d/%d/%d default/read/poll queues\n",
868 vscsi->io_queues[HCTX_TYPE_DEFAULT],
869 vscsi->io_queues[HCTX_TYPE_READ],
870 vscsi->io_queues[HCTX_TYPE_POLL]);
872 callbacks[0] = virtscsi_ctrl_done;
873 callbacks[1] = virtscsi_event_done;
874 names[0] = "control";
876 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs - num_poll_vqs; i++) {
877 callbacks[i] = virtscsi_req_done;
878 names[i] = "request";
881 for (; i < num_vqs; i++) {
883 names[i] = "request_poll";
886 /* Discover virtqueues and write information to configuration. */
887 err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
891 virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
892 virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
893 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
894 virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
897 virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
898 virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
907 virtscsi_remove_vqs(vdev);
911 static int virtscsi_probe(struct virtio_device *vdev)
913 struct Scsi_Host *shost;
914 struct virtio_scsi *vscsi;
916 u32 sg_elems, num_targets;
920 if (!vdev->config->get) {
921 dev_err(&vdev->dev, "%s failure: config access disabled\n",
926 /* We need to know how many queues before we allocate. */
927 num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
928 num_queues = min_t(unsigned int, nr_cpu_ids, num_queues);
930 num_targets = virtscsi_config_get(vdev, max_target) + 1;
932 shost = scsi_host_alloc(&virtscsi_host_template,
933 struct_size(vscsi, req_vqs, num_queues));
937 sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
938 shost->sg_tablesize = sg_elems;
940 vscsi = shost_priv(shost);
942 vscsi->num_queues = num_queues;
945 err = virtscsi_init(vdev, vscsi);
947 goto virtscsi_init_failed;
949 if (vscsi->io_queues[HCTX_TYPE_POLL])
950 shost->nr_maps = HCTX_TYPE_POLL + 1;
952 shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq);
954 cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
955 shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
956 shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
958 /* LUNs > 256 are reported with format 1, so they go in the range
961 shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
962 shost->max_id = num_targets;
963 shost->max_channel = 0;
964 shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
965 shost->nr_hw_queues = num_queues;
967 #ifdef CONFIG_BLK_DEV_INTEGRITY
968 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) {
971 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
972 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
973 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
975 scsi_host_set_prot(shost, host_prot);
976 scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC);
980 err = scsi_add_host(shost, &vdev->dev);
982 goto scsi_add_host_failed;
984 virtio_device_ready(vdev);
986 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
987 virtscsi_kick_event_all(vscsi);
989 scsi_scan_host(shost);
992 scsi_add_host_failed:
993 vdev->config->del_vqs(vdev);
994 virtscsi_init_failed:
995 scsi_host_put(shost);
999 static void virtscsi_remove(struct virtio_device *vdev)
1001 struct Scsi_Host *shost = virtio_scsi_host(vdev);
1002 struct virtio_scsi *vscsi = shost_priv(shost);
1004 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
1005 virtscsi_cancel_event_work(vscsi);
1007 scsi_remove_host(shost);
1008 virtscsi_remove_vqs(vdev);
1009 scsi_host_put(shost);
1012 #ifdef CONFIG_PM_SLEEP
1013 static int virtscsi_freeze(struct virtio_device *vdev)
1015 virtscsi_remove_vqs(vdev);
1019 static int virtscsi_restore(struct virtio_device *vdev)
1021 struct Scsi_Host *sh = virtio_scsi_host(vdev);
1022 struct virtio_scsi *vscsi = shost_priv(sh);
1025 err = virtscsi_init(vdev, vscsi);
1029 virtio_device_ready(vdev);
1031 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
1032 virtscsi_kick_event_all(vscsi);
1038 static struct virtio_device_id id_table[] = {
1039 { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID },
1043 static unsigned int features[] = {
1044 VIRTIO_SCSI_F_HOTPLUG,
1045 VIRTIO_SCSI_F_CHANGE,
1046 #ifdef CONFIG_BLK_DEV_INTEGRITY
1047 VIRTIO_SCSI_F_T10_PI,
1051 static struct virtio_driver virtio_scsi_driver = {
1052 .feature_table = features,
1053 .feature_table_size = ARRAY_SIZE(features),
1054 .driver.name = KBUILD_MODNAME,
1055 .driver.owner = THIS_MODULE,
1056 .id_table = id_table,
1057 .probe = virtscsi_probe,
1058 #ifdef CONFIG_PM_SLEEP
1059 .freeze = virtscsi_freeze,
1060 .restore = virtscsi_restore,
1062 .remove = virtscsi_remove,
1065 static int __init virtio_scsi_init(void)
1069 virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
1070 if (!virtscsi_cmd_cache) {
1071 pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
1077 mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
1078 virtscsi_cmd_cache);
1079 if (!virtscsi_cmd_pool) {
1080 pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
1083 ret = register_virtio_driver(&virtio_scsi_driver);
1090 mempool_destroy(virtscsi_cmd_pool);
1091 virtscsi_cmd_pool = NULL;
1092 kmem_cache_destroy(virtscsi_cmd_cache);
1093 virtscsi_cmd_cache = NULL;
1097 static void __exit virtio_scsi_fini(void)
1099 unregister_virtio_driver(&virtio_scsi_driver);
1100 mempool_destroy(virtscsi_cmd_pool);
1101 kmem_cache_destroy(virtscsi_cmd_cache);
1103 module_init(virtio_scsi_init);
1104 module_exit(virtio_scsi_fini);
1106 MODULE_DEVICE_TABLE(virtio, id_table);
1107 MODULE_DESCRIPTION("Virtio SCSI HBA driver");
1108 MODULE_LICENSE("GPL");