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13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14
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 <scsi/scsi_host.h>
26#include <scsi/scsi_device.h>
27#include <scsi/scsi_cmnd.h>
28#include <scsi/scsi_tcq.h>
29#include <scsi/scsi_devinfo.h>
30#include <linux/seqlock.h>
31#include <linux/blk-mq-virtio.h>
32
33#define VIRTIO_SCSI_MEMPOOL_SZ 64
34#define VIRTIO_SCSI_EVENT_LEN 8
35#define VIRTIO_SCSI_VQ_BASE 2
36
37
38struct virtio_scsi_cmd {
39 struct scsi_cmnd *sc;
40 struct completion *comp;
41 union {
42 struct virtio_scsi_cmd_req cmd;
43 struct virtio_scsi_cmd_req_pi cmd_pi;
44 struct virtio_scsi_ctrl_tmf_req tmf;
45 struct virtio_scsi_ctrl_an_req an;
46 } req;
47 union {
48 struct virtio_scsi_cmd_resp cmd;
49 struct virtio_scsi_ctrl_tmf_resp tmf;
50 struct virtio_scsi_ctrl_an_resp an;
51 struct virtio_scsi_event evt;
52 } resp;
53} ____cacheline_aligned_in_smp;
54
55struct virtio_scsi_event_node {
56 struct virtio_scsi *vscsi;
57 struct virtio_scsi_event event;
58 struct work_struct work;
59};
60
61struct virtio_scsi_vq {
62
63 spinlock_t vq_lock;
64
65 struct virtqueue *vq;
66};
67
68
69struct virtio_scsi {
70 struct virtio_device *vdev;
71
72
73 struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
74
75 u32 num_queues;
76
77 struct hlist_node node;
78
79
80 bool stop_events;
81
82 struct virtio_scsi_vq ctrl_vq;
83 struct virtio_scsi_vq event_vq;
84 struct virtio_scsi_vq req_vqs[];
85};
86
87static struct kmem_cache *virtscsi_cmd_cache;
88static mempool_t *virtscsi_cmd_pool;
89
90static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
91{
92 return vdev->priv;
93}
94
95static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
96{
97 if (resid)
98 scsi_set_resid(sc, resid);
99}
100
101
102
103
104
105
106static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
107{
108 struct virtio_scsi_cmd *cmd = buf;
109 struct scsi_cmnd *sc = cmd->sc;
110 struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
111
112 dev_dbg(&sc->device->sdev_gendev,
113 "cmd %p response %u status %#02x sense_len %u\n",
114 sc, resp->response, resp->status, resp->sense_len);
115
116 sc->result = resp->status;
117 virtscsi_compute_resid(sc, virtio32_to_cpu(vscsi->vdev, resp->resid));
118 switch (resp->response) {
119 case VIRTIO_SCSI_S_OK:
120 set_host_byte(sc, DID_OK);
121 break;
122 case VIRTIO_SCSI_S_OVERRUN:
123 set_host_byte(sc, DID_ERROR);
124 break;
125 case VIRTIO_SCSI_S_ABORTED:
126 set_host_byte(sc, DID_ABORT);
127 break;
128 case VIRTIO_SCSI_S_BAD_TARGET:
129 set_host_byte(sc, DID_BAD_TARGET);
130 break;
131 case VIRTIO_SCSI_S_RESET:
132 set_host_byte(sc, DID_RESET);
133 break;
134 case VIRTIO_SCSI_S_BUSY:
135 set_host_byte(sc, DID_BUS_BUSY);
136 break;
137 case VIRTIO_SCSI_S_TRANSPORT_FAILURE:
138 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
139 break;
140 case VIRTIO_SCSI_S_TARGET_FAILURE:
141 set_host_byte(sc, DID_TARGET_FAILURE);
142 break;
143 case VIRTIO_SCSI_S_NEXUS_FAILURE:
144 set_host_byte(sc, DID_NEXUS_FAILURE);
145 break;
146 default:
147 scmd_printk(KERN_WARNING, sc, "Unknown response %d",
148 resp->response);
149
150 case VIRTIO_SCSI_S_FAILURE:
151 set_host_byte(sc, DID_ERROR);
152 break;
153 }
154
155 WARN_ON(virtio32_to_cpu(vscsi->vdev, resp->sense_len) >
156 VIRTIO_SCSI_SENSE_SIZE);
157 if (sc->sense_buffer) {
158 memcpy(sc->sense_buffer, resp->sense,
159 min_t(u32,
160 virtio32_to_cpu(vscsi->vdev, resp->sense_len),
161 VIRTIO_SCSI_SENSE_SIZE));
162 if (resp->sense_len)
163 set_driver_byte(sc, DRIVER_SENSE);
164 }
165
166 sc->scsi_done(sc);
167}
168
169static void virtscsi_vq_done(struct virtio_scsi *vscsi,
170 struct virtio_scsi_vq *virtscsi_vq,
171 void (*fn)(struct virtio_scsi *vscsi, void *buf))
172{
173 void *buf;
174 unsigned int len;
175 unsigned long flags;
176 struct virtqueue *vq = virtscsi_vq->vq;
177
178 spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
179 do {
180 virtqueue_disable_cb(vq);
181 while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
182 fn(vscsi, buf);
183
184 if (unlikely(virtqueue_is_broken(vq)))
185 break;
186 } while (!virtqueue_enable_cb(vq));
187 spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
188}
189
190static void virtscsi_req_done(struct virtqueue *vq)
191{
192 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
193 struct virtio_scsi *vscsi = shost_priv(sh);
194 int index = vq->index - VIRTIO_SCSI_VQ_BASE;
195 struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
196
197 virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
198};
199
200static void virtscsi_poll_requests(struct virtio_scsi *vscsi)
201{
202 int i, num_vqs;
203
204 num_vqs = vscsi->num_queues;
205 for (i = 0; i < num_vqs; i++)
206 virtscsi_vq_done(vscsi, &vscsi->req_vqs[i],
207 virtscsi_complete_cmd);
208}
209
210static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
211{
212 struct virtio_scsi_cmd *cmd = buf;
213
214 if (cmd->comp)
215 complete(cmd->comp);
216}
217
218static void virtscsi_ctrl_done(struct virtqueue *vq)
219{
220 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
221 struct virtio_scsi *vscsi = shost_priv(sh);
222
223 virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
224};
225
226static void virtscsi_handle_event(struct work_struct *work);
227
228static int virtscsi_kick_event(struct virtio_scsi *vscsi,
229 struct virtio_scsi_event_node *event_node)
230{
231 int err;
232 struct scatterlist sg;
233 unsigned long flags;
234
235 INIT_WORK(&event_node->work, virtscsi_handle_event);
236 sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
237
238 spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
239
240 err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
241 GFP_ATOMIC);
242 if (!err)
243 virtqueue_kick(vscsi->event_vq.vq);
244
245 spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
246
247 return err;
248}
249
250static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
251{
252 int i;
253
254 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
255 vscsi->event_list[i].vscsi = vscsi;
256 virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
257 }
258
259 return 0;
260}
261
262static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
263{
264 int i;
265
266
267 spin_lock_irq(&vscsi->event_vq.vq_lock);
268 vscsi->stop_events = true;
269 spin_unlock_irq(&vscsi->event_vq.vq_lock);
270
271 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
272 cancel_work_sync(&vscsi->event_list[i].work);
273}
274
275static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
276 struct virtio_scsi_event *event)
277{
278 struct scsi_device *sdev;
279 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
280 unsigned int target = event->lun[1];
281 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
282
283 switch (virtio32_to_cpu(vscsi->vdev, event->reason)) {
284 case VIRTIO_SCSI_EVT_RESET_RESCAN:
285 scsi_add_device(shost, 0, target, lun);
286 break;
287 case VIRTIO_SCSI_EVT_RESET_REMOVED:
288 sdev = scsi_device_lookup(shost, 0, target, lun);
289 if (sdev) {
290 scsi_remove_device(sdev);
291 scsi_device_put(sdev);
292 } else {
293 pr_err("SCSI device %d 0 %d %d not found\n",
294 shost->host_no, target, lun);
295 }
296 break;
297 default:
298 pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
299 }
300}
301
302static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
303 struct virtio_scsi_event *event)
304{
305 struct scsi_device *sdev;
306 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
307 unsigned int target = event->lun[1];
308 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
309 u8 asc = virtio32_to_cpu(vscsi->vdev, event->reason) & 255;
310 u8 ascq = virtio32_to_cpu(vscsi->vdev, event->reason) >> 8;
311
312 sdev = scsi_device_lookup(shost, 0, target, lun);
313 if (!sdev) {
314 pr_err("SCSI device %d 0 %d %d not found\n",
315 shost->host_no, target, lun);
316 return;
317 }
318
319
320
321 if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
322 scsi_rescan_device(&sdev->sdev_gendev);
323
324 scsi_device_put(sdev);
325}
326
327static void virtscsi_handle_event(struct work_struct *work)
328{
329 struct virtio_scsi_event_node *event_node =
330 container_of(work, struct virtio_scsi_event_node, work);
331 struct virtio_scsi *vscsi = event_node->vscsi;
332 struct virtio_scsi_event *event = &event_node->event;
333
334 if (event->event &
335 cpu_to_virtio32(vscsi->vdev, VIRTIO_SCSI_T_EVENTS_MISSED)) {
336 event->event &= ~cpu_to_virtio32(vscsi->vdev,
337 VIRTIO_SCSI_T_EVENTS_MISSED);
338 scsi_scan_host(virtio_scsi_host(vscsi->vdev));
339 }
340
341 switch (virtio32_to_cpu(vscsi->vdev, event->event)) {
342 case VIRTIO_SCSI_T_NO_EVENT:
343 break;
344 case VIRTIO_SCSI_T_TRANSPORT_RESET:
345 virtscsi_handle_transport_reset(vscsi, event);
346 break;
347 case VIRTIO_SCSI_T_PARAM_CHANGE:
348 virtscsi_handle_param_change(vscsi, event);
349 break;
350 default:
351 pr_err("Unsupport virtio scsi event %x\n", event->event);
352 }
353 virtscsi_kick_event(vscsi, event_node);
354}
355
356static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
357{
358 struct virtio_scsi_event_node *event_node = buf;
359
360 if (!vscsi->stop_events)
361 queue_work(system_freezable_wq, &event_node->work);
362}
363
364static void virtscsi_event_done(struct virtqueue *vq)
365{
366 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
367 struct virtio_scsi *vscsi = shost_priv(sh);
368
369 virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
370};
371
372
373
374
375
376
377
378
379static int virtscsi_add_cmd(struct virtqueue *vq,
380 struct virtio_scsi_cmd *cmd,
381 size_t req_size, size_t resp_size)
382{
383 struct scsi_cmnd *sc = cmd->sc;
384 struct scatterlist *sgs[6], req, resp;
385 struct sg_table *out, *in;
386 unsigned out_num = 0, in_num = 0;
387
388 out = in = NULL;
389
390 if (sc && sc->sc_data_direction != DMA_NONE) {
391 if (sc->sc_data_direction != DMA_FROM_DEVICE)
392 out = &sc->sdb.table;
393 if (sc->sc_data_direction != DMA_TO_DEVICE)
394 in = &sc->sdb.table;
395 }
396
397
398 sg_init_one(&req, &cmd->req, req_size);
399 sgs[out_num++] = &req;
400
401
402 if (out) {
403
404 if (scsi_prot_sg_count(sc))
405 sgs[out_num++] = scsi_prot_sglist(sc);
406 sgs[out_num++] = out->sgl;
407 }
408
409
410 sg_init_one(&resp, &cmd->resp, resp_size);
411 sgs[out_num + in_num++] = &resp;
412
413
414 if (in) {
415
416 if (scsi_prot_sg_count(sc))
417 sgs[out_num + in_num++] = scsi_prot_sglist(sc);
418 sgs[out_num + in_num++] = in->sgl;
419 }
420
421 return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC);
422}
423
424static int virtscsi_kick_cmd(struct virtio_scsi_vq *vq,
425 struct virtio_scsi_cmd *cmd,
426 size_t req_size, size_t resp_size)
427{
428 unsigned long flags;
429 int err;
430 bool needs_kick = false;
431
432 spin_lock_irqsave(&vq->vq_lock, flags);
433 err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size);
434 if (!err)
435 needs_kick = virtqueue_kick_prepare(vq->vq);
436
437 spin_unlock_irqrestore(&vq->vq_lock, flags);
438
439 if (needs_kick)
440 virtqueue_notify(vq->vq);
441 return err;
442}
443
444static void virtio_scsi_init_hdr(struct virtio_device *vdev,
445 struct virtio_scsi_cmd_req *cmd,
446 struct scsi_cmnd *sc)
447{
448 cmd->lun[0] = 1;
449 cmd->lun[1] = sc->device->id;
450 cmd->lun[2] = (sc->device->lun >> 8) | 0x40;
451 cmd->lun[3] = sc->device->lun & 0xff;
452 cmd->tag = cpu_to_virtio64(vdev, (unsigned long)sc);
453 cmd->task_attr = VIRTIO_SCSI_S_SIMPLE;
454 cmd->prio = 0;
455 cmd->crn = 0;
456}
457
458#ifdef CONFIG_BLK_DEV_INTEGRITY
459static void virtio_scsi_init_hdr_pi(struct virtio_device *vdev,
460 struct virtio_scsi_cmd_req_pi *cmd_pi,
461 struct scsi_cmnd *sc)
462{
463 struct request *rq = sc->request;
464 struct blk_integrity *bi;
465
466 virtio_scsi_init_hdr(vdev, (struct virtio_scsi_cmd_req *)cmd_pi, sc);
467
468 if (!rq || !scsi_prot_sg_count(sc))
469 return;
470
471 bi = blk_get_integrity(rq->rq_disk);
472
473 if (sc->sc_data_direction == DMA_TO_DEVICE)
474 cmd_pi->pi_bytesout = cpu_to_virtio32(vdev,
475 bio_integrity_bytes(bi,
476 blk_rq_sectors(rq)));
477 else if (sc->sc_data_direction == DMA_FROM_DEVICE)
478 cmd_pi->pi_bytesin = cpu_to_virtio32(vdev,
479 bio_integrity_bytes(bi,
480 blk_rq_sectors(rq)));
481}
482#endif
483
484static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi,
485 struct scsi_cmnd *sc)
486{
487 u32 tag = blk_mq_unique_tag(sc->request);
488 u16 hwq = blk_mq_unique_tag_to_hwq(tag);
489
490 return &vscsi->req_vqs[hwq];
491}
492
493static int virtscsi_queuecommand(struct Scsi_Host *shost,
494 struct scsi_cmnd *sc)
495{
496 struct virtio_scsi *vscsi = shost_priv(shost);
497 struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc);
498 struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc);
499 unsigned long flags;
500 int req_size;
501 int ret;
502
503 BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize);
504
505
506 BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL);
507
508 dev_dbg(&sc->device->sdev_gendev,
509 "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]);
510
511 cmd->sc = sc;
512
513 BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
514
515#ifdef CONFIG_BLK_DEV_INTEGRITY
516 if (virtio_has_feature(vscsi->vdev, VIRTIO_SCSI_F_T10_PI)) {
517 virtio_scsi_init_hdr_pi(vscsi->vdev, &cmd->req.cmd_pi, sc);
518 memcpy(cmd->req.cmd_pi.cdb, sc->cmnd, sc->cmd_len);
519 req_size = sizeof(cmd->req.cmd_pi);
520 } else
521#endif
522 {
523 virtio_scsi_init_hdr(vscsi->vdev, &cmd->req.cmd, sc);
524 memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
525 req_size = sizeof(cmd->req.cmd);
526 }
527
528 ret = virtscsi_kick_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd));
529 if (ret == -EIO) {
530 cmd->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
531 spin_lock_irqsave(&req_vq->vq_lock, flags);
532 virtscsi_complete_cmd(vscsi, cmd);
533 spin_unlock_irqrestore(&req_vq->vq_lock, flags);
534 } else if (ret != 0) {
535 return SCSI_MLQUEUE_HOST_BUSY;
536 }
537 return 0;
538}
539
540static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
541{
542 DECLARE_COMPLETION_ONSTACK(comp);
543 int ret = FAILED;
544
545 cmd->comp = ∁
546 if (virtscsi_kick_cmd(&vscsi->ctrl_vq, cmd,
547 sizeof cmd->req.tmf, sizeof cmd->resp.tmf) < 0)
548 goto out;
549
550 wait_for_completion(&comp);
551 if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
552 cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
553 ret = SUCCESS;
554
555
556
557
558
559
560
561
562
563
564
565 virtscsi_poll_requests(vscsi);
566
567out:
568 mempool_free(cmd, virtscsi_cmd_pool);
569 return ret;
570}
571
572static int virtscsi_device_reset(struct scsi_cmnd *sc)
573{
574 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
575 struct virtio_scsi_cmd *cmd;
576
577 sdev_printk(KERN_INFO, sc->device, "device reset\n");
578 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
579 if (!cmd)
580 return FAILED;
581
582 memset(cmd, 0, sizeof(*cmd));
583 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
584 .type = VIRTIO_SCSI_T_TMF,
585 .subtype = cpu_to_virtio32(vscsi->vdev,
586 VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET),
587 .lun[0] = 1,
588 .lun[1] = sc->device->id,
589 .lun[2] = (sc->device->lun >> 8) | 0x40,
590 .lun[3] = sc->device->lun & 0xff,
591 };
592 return virtscsi_tmf(vscsi, cmd);
593}
594
595static int virtscsi_device_alloc(struct scsi_device *sdevice)
596{
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611 sdevice->sdev_bflags = BLIST_TRY_VPD_PAGES;
612
613 return 0;
614}
615
616
617
618
619
620
621
622static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
623{
624 struct Scsi_Host *shost = sdev->host;
625 int max_depth = shost->cmd_per_lun;
626
627 return scsi_change_queue_depth(sdev, min(max_depth, qdepth));
628}
629
630static int virtscsi_abort(struct scsi_cmnd *sc)
631{
632 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
633 struct virtio_scsi_cmd *cmd;
634
635 scmd_printk(KERN_INFO, sc, "abort\n");
636 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
637 if (!cmd)
638 return FAILED;
639
640 memset(cmd, 0, sizeof(*cmd));
641 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
642 .type = VIRTIO_SCSI_T_TMF,
643 .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
644 .lun[0] = 1,
645 .lun[1] = sc->device->id,
646 .lun[2] = (sc->device->lun >> 8) | 0x40,
647 .lun[3] = sc->device->lun & 0xff,
648 .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc),
649 };
650 return virtscsi_tmf(vscsi, cmd);
651}
652
653static int virtscsi_map_queues(struct Scsi_Host *shost)
654{
655 struct virtio_scsi *vscsi = shost_priv(shost);
656 struct blk_mq_queue_map *qmap = &shost->tag_set.map[HCTX_TYPE_DEFAULT];
657
658 return blk_mq_virtio_map_queues(qmap, vscsi->vdev, 2);
659}
660
661
662
663
664
665
666static enum blk_eh_timer_return virtscsi_eh_timed_out(struct scsi_cmnd *scmnd)
667{
668 return BLK_EH_RESET_TIMER;
669}
670
671static struct scsi_host_template virtscsi_host_template = {
672 .module = THIS_MODULE,
673 .name = "Virtio SCSI HBA",
674 .proc_name = "virtio_scsi",
675 .this_id = -1,
676 .cmd_size = sizeof(struct virtio_scsi_cmd),
677 .queuecommand = virtscsi_queuecommand,
678 .change_queue_depth = virtscsi_change_queue_depth,
679 .eh_abort_handler = virtscsi_abort,
680 .eh_device_reset_handler = virtscsi_device_reset,
681 .eh_timed_out = virtscsi_eh_timed_out,
682 .slave_alloc = virtscsi_device_alloc,
683
684 .dma_boundary = UINT_MAX,
685 .map_queues = virtscsi_map_queues,
686 .track_queue_depth = 1,
687 .force_blk_mq = 1,
688};
689
690#define virtscsi_config_get(vdev, fld) \
691 ({ \
692 typeof(((struct virtio_scsi_config *)0)->fld) __val; \
693 virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \
694 __val; \
695 })
696
697#define virtscsi_config_set(vdev, fld, val) \
698 do { \
699 typeof(((struct virtio_scsi_config *)0)->fld) __val = (val); \
700 virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \
701 } while(0)
702
703static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
704 struct virtqueue *vq)
705{
706 spin_lock_init(&virtscsi_vq->vq_lock);
707 virtscsi_vq->vq = vq;
708}
709
710static void virtscsi_remove_vqs(struct virtio_device *vdev)
711{
712
713 vdev->config->reset(vdev);
714 vdev->config->del_vqs(vdev);
715}
716
717static int virtscsi_init(struct virtio_device *vdev,
718 struct virtio_scsi *vscsi)
719{
720 int err;
721 u32 i;
722 u32 num_vqs;
723 vq_callback_t **callbacks;
724 const char **names;
725 struct virtqueue **vqs;
726 struct irq_affinity desc = { .pre_vectors = 2 };
727
728 num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE;
729 vqs = kmalloc_array(num_vqs, sizeof(struct virtqueue *), GFP_KERNEL);
730 callbacks = kmalloc_array(num_vqs, sizeof(vq_callback_t *),
731 GFP_KERNEL);
732 names = kmalloc_array(num_vqs, sizeof(char *), GFP_KERNEL);
733
734 if (!callbacks || !vqs || !names) {
735 err = -ENOMEM;
736 goto out;
737 }
738
739 callbacks[0] = virtscsi_ctrl_done;
740 callbacks[1] = virtscsi_event_done;
741 names[0] = "control";
742 names[1] = "event";
743 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) {
744 callbacks[i] = virtscsi_req_done;
745 names[i] = "request";
746 }
747
748
749 err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
750 if (err)
751 goto out;
752
753 virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
754 virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
755 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
756 virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
757 vqs[i]);
758
759 virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
760 virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
761
762 err = 0;
763
764out:
765 kfree(names);
766 kfree(callbacks);
767 kfree(vqs);
768 if (err)
769 virtscsi_remove_vqs(vdev);
770 return err;
771}
772
773static int virtscsi_probe(struct virtio_device *vdev)
774{
775 struct Scsi_Host *shost;
776 struct virtio_scsi *vscsi;
777 int err;
778 u32 sg_elems, num_targets;
779 u32 cmd_per_lun;
780 u32 num_queues;
781
782 if (!vdev->config->get) {
783 dev_err(&vdev->dev, "%s failure: config access disabled\n",
784 __func__);
785 return -EINVAL;
786 }
787
788
789 num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
790 num_queues = min_t(unsigned int, nr_cpu_ids, num_queues);
791
792 num_targets = virtscsi_config_get(vdev, max_target) + 1;
793
794 shost = scsi_host_alloc(&virtscsi_host_template,
795 struct_size(vscsi, req_vqs, num_queues));
796 if (!shost)
797 return -ENOMEM;
798
799 sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
800 shost->sg_tablesize = sg_elems;
801 vscsi = shost_priv(shost);
802 vscsi->vdev = vdev;
803 vscsi->num_queues = num_queues;
804 vdev->priv = shost;
805
806 err = virtscsi_init(vdev, vscsi);
807 if (err)
808 goto virtscsi_init_failed;
809
810 shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq);
811
812 cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
813 shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
814 shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
815
816
817
818
819 shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
820 shost->max_id = num_targets;
821 shost->max_channel = 0;
822 shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
823 shost->nr_hw_queues = num_queues;
824
825#ifdef CONFIG_BLK_DEV_INTEGRITY
826 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) {
827 int host_prot;
828
829 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
830 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
831 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
832
833 scsi_host_set_prot(shost, host_prot);
834 scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC);
835 }
836#endif
837
838 err = scsi_add_host(shost, &vdev->dev);
839 if (err)
840 goto scsi_add_host_failed;
841
842 virtio_device_ready(vdev);
843
844 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
845 virtscsi_kick_event_all(vscsi);
846
847 scsi_scan_host(shost);
848 return 0;
849
850scsi_add_host_failed:
851 vdev->config->del_vqs(vdev);
852virtscsi_init_failed:
853 scsi_host_put(shost);
854 return err;
855}
856
857static void virtscsi_remove(struct virtio_device *vdev)
858{
859 struct Scsi_Host *shost = virtio_scsi_host(vdev);
860 struct virtio_scsi *vscsi = shost_priv(shost);
861
862 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
863 virtscsi_cancel_event_work(vscsi);
864
865 scsi_remove_host(shost);
866 virtscsi_remove_vqs(vdev);
867 scsi_host_put(shost);
868}
869
870#ifdef CONFIG_PM_SLEEP
871static int virtscsi_freeze(struct virtio_device *vdev)
872{
873 virtscsi_remove_vqs(vdev);
874 return 0;
875}
876
877static int virtscsi_restore(struct virtio_device *vdev)
878{
879 struct Scsi_Host *sh = virtio_scsi_host(vdev);
880 struct virtio_scsi *vscsi = shost_priv(sh);
881 int err;
882
883 err = virtscsi_init(vdev, vscsi);
884 if (err)
885 return err;
886
887 virtio_device_ready(vdev);
888
889 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
890 virtscsi_kick_event_all(vscsi);
891
892 return err;
893}
894#endif
895
896static struct virtio_device_id id_table[] = {
897 { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID },
898 { 0 },
899};
900
901static unsigned int features[] = {
902 VIRTIO_SCSI_F_HOTPLUG,
903 VIRTIO_SCSI_F_CHANGE,
904#ifdef CONFIG_BLK_DEV_INTEGRITY
905 VIRTIO_SCSI_F_T10_PI,
906#endif
907};
908
909static struct virtio_driver virtio_scsi_driver = {
910 .feature_table = features,
911 .feature_table_size = ARRAY_SIZE(features),
912 .driver.name = KBUILD_MODNAME,
913 .driver.owner = THIS_MODULE,
914 .id_table = id_table,
915 .probe = virtscsi_probe,
916#ifdef CONFIG_PM_SLEEP
917 .freeze = virtscsi_freeze,
918 .restore = virtscsi_restore,
919#endif
920 .remove = virtscsi_remove,
921};
922
923static int __init init(void)
924{
925 int ret = -ENOMEM;
926
927 virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
928 if (!virtscsi_cmd_cache) {
929 pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
930 goto error;
931 }
932
933
934 virtscsi_cmd_pool =
935 mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
936 virtscsi_cmd_cache);
937 if (!virtscsi_cmd_pool) {
938 pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
939 goto error;
940 }
941 ret = register_virtio_driver(&virtio_scsi_driver);
942 if (ret < 0)
943 goto error;
944
945 return 0;
946
947error:
948 if (virtscsi_cmd_pool) {
949 mempool_destroy(virtscsi_cmd_pool);
950 virtscsi_cmd_pool = NULL;
951 }
952 if (virtscsi_cmd_cache) {
953 kmem_cache_destroy(virtscsi_cmd_cache);
954 virtscsi_cmd_cache = NULL;
955 }
956 return ret;
957}
958
959static void __exit fini(void)
960{
961 unregister_virtio_driver(&virtio_scsi_driver);
962 mempool_destroy(virtscsi_cmd_pool);
963 kmem_cache_destroy(virtscsi_cmd_cache);
964}
965module_init(init);
966module_exit(fini);
967
968MODULE_DEVICE_TABLE(virtio, id_table);
969MODULE_DESCRIPTION("Virtio SCSI HBA driver");
970MODULE_LICENSE("GPL");
971
