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Merge tag 'regmap-fix-v5.11-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux/fpc-iii.git] / drivers / scsi / virtio_scsi.c
blobb9c86a7e3b97d6e5adea59063d89e2a2fe2fc014
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Virtio SCSI HBA driver
4 *
5 * Copyright IBM Corp. 2010
6 * Copyright Red Hat, Inc. 2011
7 *
8 * Authors:
9 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
10 * Paolo Bonzini <pbonzini@redhat.com>
11 */
12
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 #include "sd.h"
34
35 #define VIRTIO_SCSI_MEMPOOL_SZ 64
36 #define VIRTIO_SCSI_EVENT_LEN 8
37 #define VIRTIO_SCSI_VQ_BASE 2
38
39 /* Command queue element */
40 struct virtio_scsi_cmd {
41 struct scsi_cmnd *sc;
42 struct completion *comp;
43 union {
44 struct virtio_scsi_cmd_req cmd;
45 struct virtio_scsi_cmd_req_pi cmd_pi;
46 struct virtio_scsi_ctrl_tmf_req tmf;
47 struct virtio_scsi_ctrl_an_req an;
48 } req;
49 union {
50 struct virtio_scsi_cmd_resp cmd;
51 struct virtio_scsi_ctrl_tmf_resp tmf;
52 struct virtio_scsi_ctrl_an_resp an;
53 struct virtio_scsi_event evt;
54 } resp;
55 } ____cacheline_aligned_in_smp;
56
57 struct virtio_scsi_event_node {
58 struct virtio_scsi *vscsi;
59 struct virtio_scsi_event event;
60 struct work_struct work;
61 };
62
63 struct virtio_scsi_vq {
64 /* Protects vq */
65 spinlock_t vq_lock;
66
67 struct virtqueue *vq;
68 };
69
70 /* Driver instance state */
71 struct virtio_scsi {
72 struct virtio_device *vdev;
73
74 /* Get some buffers ready for event vq */
75 struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
76
77 u32 num_queues;
78
79 struct hlist_node node;
80
81 /* Protected by event_vq lock */
82 bool stop_events;
83
84 struct virtio_scsi_vq ctrl_vq;
85 struct virtio_scsi_vq event_vq;
86 struct virtio_scsi_vq req_vqs[];
87 };
88
89 static struct kmem_cache *virtscsi_cmd_cache;
90 static mempool_t *virtscsi_cmd_pool;
91
92 static inline struct Scsi_Host *virtio_scsi_host(struct virtio_device *vdev)
93 {
94 return vdev->priv;
95 }
96
97 static void virtscsi_compute_resid(struct scsi_cmnd *sc, u32 resid)
98 {
99 if (resid)
100 scsi_set_resid(sc, resid);
101 }
102
103 /*
104 * virtscsi_complete_cmd - finish a scsi_cmd and invoke scsi_done
105 *
106 * Called with vq_lock held.
107 */
108 static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf)
109 {
110 struct virtio_scsi_cmd *cmd = buf;
111 struct scsi_cmnd *sc = cmd->sc;
112 struct virtio_scsi_cmd_resp *resp = &cmd->resp.cmd;
113
114 dev_dbg(&sc->device->sdev_gendev,
115 "cmd %p response %u status %#02x sense_len %u\n",
116 sc, resp->response, resp->status, resp->sense_len);
117
118 sc->result = resp->status;
119 virtscsi_compute_resid(sc, virtio32_to_cpu(vscsi->vdev, resp->resid));
120 switch (resp->response) {
121 case VIRTIO_SCSI_S_OK:
122 set_host_byte(sc, DID_OK);
123 break;
124 case VIRTIO_SCSI_S_OVERRUN:
125 set_host_byte(sc, DID_ERROR);
126 break;
127 case VIRTIO_SCSI_S_ABORTED:
128 set_host_byte(sc, DID_ABORT);
129 break;
130 case VIRTIO_SCSI_S_BAD_TARGET:
131 set_host_byte(sc, DID_BAD_TARGET);
132 break;
133 case VIRTIO_SCSI_S_RESET:
134 set_host_byte(sc, DID_RESET);
135 break;
136 case VIRTIO_SCSI_S_BUSY:
137 set_host_byte(sc, DID_BUS_BUSY);
138 break;
139 case VIRTIO_SCSI_S_TRANSPORT_FAILURE:
140 set_host_byte(sc, DID_TRANSPORT_DISRUPTED);
141 break;
142 case VIRTIO_SCSI_S_TARGET_FAILURE:
143 set_host_byte(sc, DID_TARGET_FAILURE);
144 break;
145 case VIRTIO_SCSI_S_NEXUS_FAILURE:
146 set_host_byte(sc, DID_NEXUS_FAILURE);
147 break;
148 default:
149 scmd_printk(KERN_WARNING, sc, "Unknown response %d",
150 resp->response);
151 fallthrough;
152 case VIRTIO_SCSI_S_FAILURE:
153 set_host_byte(sc, DID_ERROR);
154 break;
155 }
156
157 WARN_ON(virtio32_to_cpu(vscsi->vdev, resp->sense_len) >
158 VIRTIO_SCSI_SENSE_SIZE);
159 if (sc->sense_buffer) {
160 memcpy(sc->sense_buffer, resp->sense,
161 min_t(u32,
162 virtio32_to_cpu(vscsi->vdev, resp->sense_len),
163 VIRTIO_SCSI_SENSE_SIZE));
164 if (resp->sense_len)
165 set_driver_byte(sc, DRIVER_SENSE);
166 }
167
168 sc->scsi_done(sc);
169 }
170
171 static void virtscsi_vq_done(struct virtio_scsi *vscsi,
172 struct virtio_scsi_vq *virtscsi_vq,
173 void (*fn)(struct virtio_scsi *vscsi, void *buf))
174 {
175 void *buf;
176 unsigned int len;
177 unsigned long flags;
178 struct virtqueue *vq = virtscsi_vq->vq;
179
180 spin_lock_irqsave(&virtscsi_vq->vq_lock, flags);
181 do {
182 virtqueue_disable_cb(vq);
183 while ((buf = virtqueue_get_buf(vq, &len)) != NULL)
184 fn(vscsi, buf);
185
186 if (unlikely(virtqueue_is_broken(vq)))
187 break;
188 } while (!virtqueue_enable_cb(vq));
189 spin_unlock_irqrestore(&virtscsi_vq->vq_lock, flags);
190 }
191
192 static void virtscsi_req_done(struct virtqueue *vq)
193 {
194 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
195 struct virtio_scsi *vscsi = shost_priv(sh);
196 int index = vq->index - VIRTIO_SCSI_VQ_BASE;
197 struct virtio_scsi_vq *req_vq = &vscsi->req_vqs[index];
198
199 virtscsi_vq_done(vscsi, req_vq, virtscsi_complete_cmd);
200 };
201
202 static void virtscsi_poll_requests(struct virtio_scsi *vscsi)
203 {
204 int i, num_vqs;
205
206 num_vqs = vscsi->num_queues;
207 for (i = 0; i < num_vqs; i++)
208 virtscsi_vq_done(vscsi, &vscsi->req_vqs[i],
209 virtscsi_complete_cmd);
210 }
211
212 static void virtscsi_complete_free(struct virtio_scsi *vscsi, void *buf)
213 {
214 struct virtio_scsi_cmd *cmd = buf;
215
216 if (cmd->comp)
217 complete(cmd->comp);
218 }
219
220 static void virtscsi_ctrl_done(struct virtqueue *vq)
221 {
222 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
223 struct virtio_scsi *vscsi = shost_priv(sh);
224
225 virtscsi_vq_done(vscsi, &vscsi->ctrl_vq, virtscsi_complete_free);
226 };
227
228 static void virtscsi_handle_event(struct work_struct *work);
229
230 static int virtscsi_kick_event(struct virtio_scsi *vscsi,
231 struct virtio_scsi_event_node *event_node)
232 {
233 int err;
234 struct scatterlist sg;
235 unsigned long flags;
236
237 INIT_WORK(&event_node->work, virtscsi_handle_event);
238 sg_init_one(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
239
240 spin_lock_irqsave(&vscsi->event_vq.vq_lock, flags);
241
242 err = virtqueue_add_inbuf(vscsi->event_vq.vq, &sg, 1, event_node,
243 GFP_ATOMIC);
244 if (!err)
245 virtqueue_kick(vscsi->event_vq.vq);
246
247 spin_unlock_irqrestore(&vscsi->event_vq.vq_lock, flags);
248
249 return err;
250 }
251
252 static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
253 {
254 int i;
255
256 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
257 vscsi->event_list[i].vscsi = vscsi;
258 virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
259 }
260
261 return 0;
262 }
263
264 static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
265 {
266 int i;
267
268 /* Stop scheduling work before calling cancel_work_sync. */
269 spin_lock_irq(&vscsi->event_vq.vq_lock);
270 vscsi->stop_events = true;
271 spin_unlock_irq(&vscsi->event_vq.vq_lock);
272
273 for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
274 cancel_work_sync(&vscsi->event_list[i].work);
275 }
276
277 static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
278 struct virtio_scsi_event *event)
279 {
280 struct scsi_device *sdev;
281 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
282 unsigned int target = event->lun[1];
283 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
284
285 switch (virtio32_to_cpu(vscsi->vdev, event->reason)) {
286 case VIRTIO_SCSI_EVT_RESET_RESCAN:
287 if (lun == 0) {
288 scsi_scan_target(&shost->shost_gendev, 0, target,
289 SCAN_WILD_CARD, SCSI_SCAN_INITIAL);
290 } else {
291 scsi_add_device(shost, 0, target, lun);
292 }
293 break;
294 case VIRTIO_SCSI_EVT_RESET_REMOVED:
295 sdev = scsi_device_lookup(shost, 0, target, lun);
296 if (sdev) {
297 scsi_remove_device(sdev);
298 scsi_device_put(sdev);
299 } else {
300 pr_err("SCSI device %d 0 %d %d not found\n",
301 shost->host_no, target, lun);
302 }
303 break;
304 default:
305 pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
306 }
307 }
308
309 static void virtscsi_handle_param_change(struct virtio_scsi *vscsi,
310 struct virtio_scsi_event *event)
311 {
312 struct scsi_device *sdev;
313 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
314 unsigned int target = event->lun[1];
315 unsigned int lun = (event->lun[2] << 8) | event->lun[3];
316 u8 asc = virtio32_to_cpu(vscsi->vdev, event->reason) & 255;
317 u8 ascq = virtio32_to_cpu(vscsi->vdev, event->reason) >> 8;
318
319 sdev = scsi_device_lookup(shost, 0, target, lun);
320 if (!sdev) {
321 pr_err("SCSI device %d 0 %d %d not found\n",
322 shost->host_no, target, lun);
323 return;
324 }
325
326 /* Handle "Parameters changed", "Mode parameters changed", and
327 "Capacity data has changed". */
328 if (asc == 0x2a && (ascq == 0x00 || ascq == 0x01 || ascq == 0x09))
329 scsi_rescan_device(&sdev->sdev_gendev);
330
331 scsi_device_put(sdev);
332 }
333
334 static void virtscsi_rescan_hotunplug(struct virtio_scsi *vscsi)
335 {
336 struct scsi_device *sdev;
337 struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
338 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
339 int result, inquiry_len, inq_result_len = 256;
340 char *inq_result = kmalloc(inq_result_len, GFP_KERNEL);
341
342 shost_for_each_device(sdev, shost) {
343 inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
344
345 memset(scsi_cmd, 0, sizeof(scsi_cmd));
346 scsi_cmd[0] = INQUIRY;
347 scsi_cmd[4] = (unsigned char) inquiry_len;
348
349 memset(inq_result, 0, inq_result_len);
350
351 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
352 inq_result, inquiry_len, NULL,
353 SD_TIMEOUT, SD_MAX_RETRIES, NULL);
354
355 if (result == 0 && inq_result[0] >> 5) {
356 /* PQ indicates the LUN is not attached */
357 scsi_remove_device(sdev);
358 } else if (host_byte(result) == DID_BAD_TARGET) {
359 /*
360 * If all LUNs of a virtio-scsi device are unplugged
361 * it will respond with BAD TARGET on any INQUIRY
362 * command.
363 * Remove the device in this case as well.
364 */
365 scsi_remove_device(sdev);
366 }
367 }
368
369 kfree(inq_result);
370 }
371
372 static void virtscsi_handle_event(struct work_struct *work)
373 {
374 struct virtio_scsi_event_node *event_node =
375 container_of(work, struct virtio_scsi_event_node, work);
376 struct virtio_scsi *vscsi = event_node->vscsi;
377 struct virtio_scsi_event *event = &event_node->event;
378
379 if (event->event &
380 cpu_to_virtio32(vscsi->vdev, VIRTIO_SCSI_T_EVENTS_MISSED)) {
381 event->event &= ~cpu_to_virtio32(vscsi->vdev,
382 VIRTIO_SCSI_T_EVENTS_MISSED);
383 virtscsi_rescan_hotunplug(vscsi);
384 scsi_scan_host(virtio_scsi_host(vscsi->vdev));
385 }
386
387 switch (virtio32_to_cpu(vscsi->vdev, event->event)) {
388 case VIRTIO_SCSI_T_NO_EVENT:
389 break;
390 case VIRTIO_SCSI_T_TRANSPORT_RESET:
391 virtscsi_handle_transport_reset(vscsi, event);
392 break;
393 case VIRTIO_SCSI_T_PARAM_CHANGE:
394 virtscsi_handle_param_change(vscsi, event);
395 break;
396 default:
397 pr_err("Unsupport virtio scsi event %x\n", event->event);
398 }
399 virtscsi_kick_event(vscsi, event_node);
400 }
401
402 static void virtscsi_complete_event(struct virtio_scsi *vscsi, void *buf)
403 {
404 struct virtio_scsi_event_node *event_node = buf;
405
406 if (!vscsi->stop_events)
407 queue_work(system_freezable_wq, &event_node->work);
408 }
409
410 static void virtscsi_event_done(struct virtqueue *vq)
411 {
412 struct Scsi_Host *sh = virtio_scsi_host(vq->vdev);
413 struct virtio_scsi *vscsi = shost_priv(sh);
414
415 virtscsi_vq_done(vscsi, &vscsi->event_vq, virtscsi_complete_event);
416 };
417
418 static int __virtscsi_add_cmd(struct virtqueue *vq,
419 struct virtio_scsi_cmd *cmd,
420 size_t req_size, size_t resp_size)
421 {
422 struct scsi_cmnd *sc = cmd->sc;
423 struct scatterlist *sgs[6], req, resp;
424 struct sg_table *out, *in;
425 unsigned out_num = 0, in_num = 0;
426
427 out = in = NULL;
428
429 if (sc && sc->sc_data_direction != DMA_NONE) {
430 if (sc->sc_data_direction != DMA_FROM_DEVICE)
431 out = &sc->sdb.table;
432 if (sc->sc_data_direction != DMA_TO_DEVICE)
433 in = &sc->sdb.table;
434 }
435
436 /* Request header. */
437 sg_init_one(&req, &cmd->req, req_size);
438 sgs[out_num++] = &req;
439
440 /* Data-out buffer. */
441 if (out) {
442 /* Place WRITE protection SGLs before Data OUT payload */
443 if (scsi_prot_sg_count(sc))
444 sgs[out_num++] = scsi_prot_sglist(sc);
445 sgs[out_num++] = out->sgl;
446 }
447
448 /* Response header. */
449 sg_init_one(&resp, &cmd->resp, resp_size);
450 sgs[out_num + in_num++] = &resp;
451
452 /* Data-in buffer */
453 if (in) {
454 /* Place READ protection SGLs before Data IN payload */
455 if (scsi_prot_sg_count(sc))
456 sgs[out_num + in_num++] = scsi_prot_sglist(sc);
457 sgs[out_num + in_num++] = in->sgl;
458 }
459
460 return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC);
461 }
462
463 static void virtscsi_kick_vq(struct virtio_scsi_vq *vq)
464 {
465 bool needs_kick;
466 unsigned long flags;
467
468 spin_lock_irqsave(&vq->vq_lock, flags);
469 needs_kick = virtqueue_kick_prepare(vq->vq);
470 spin_unlock_irqrestore(&vq->vq_lock, flags);
471
472 if (needs_kick)
473 virtqueue_notify(vq->vq);
474 }
475
476 /**
477 * virtscsi_add_cmd - add a virtio_scsi_cmd to a virtqueue, optionally kick it
478 * @vq : the struct virtqueue we're talking about
479 * @cmd : command structure
480 * @req_size : size of the request buffer
481 * @resp_size : size of the response buffer
482 * @kick : whether to kick the virtqueue immediately
483 */
484 static int virtscsi_add_cmd(struct virtio_scsi_vq *vq,
485 struct virtio_scsi_cmd *cmd,
486 size_t req_size, size_t resp_size,
487 bool kick)
488 {
489 unsigned long flags;
490 int err;
491 bool needs_kick = false;
492
493 spin_lock_irqsave(&vq->vq_lock, flags);
494 err = __virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size);
495 if (!err && kick)
496 needs_kick = virtqueue_kick_prepare(vq->vq);
497
498 spin_unlock_irqrestore(&vq->vq_lock, flags);
499
500 if (needs_kick)
501 virtqueue_notify(vq->vq);
502 return err;
503 }
504
505 static void virtio_scsi_init_hdr(struct virtio_device *vdev,
506 struct virtio_scsi_cmd_req *cmd,
507 struct scsi_cmnd *sc)
508 {
509 cmd->lun[0] = 1;
510 cmd->lun[1] = sc->device->id;
511 cmd->lun[2] = (sc->device->lun >> 8) | 0x40;
512 cmd->lun[3] = sc->device->lun & 0xff;
513 cmd->tag = cpu_to_virtio64(vdev, (unsigned long)sc);
514 cmd->task_attr = VIRTIO_SCSI_S_SIMPLE;
515 cmd->prio = 0;
516 cmd->crn = 0;
517 }
518
519 #ifdef CONFIG_BLK_DEV_INTEGRITY
520 static void virtio_scsi_init_hdr_pi(struct virtio_device *vdev,
521 struct virtio_scsi_cmd_req_pi *cmd_pi,
522 struct scsi_cmnd *sc)
523 {
524 struct request *rq = sc->request;
525 struct blk_integrity *bi;
526
527 virtio_scsi_init_hdr(vdev, (struct virtio_scsi_cmd_req *)cmd_pi, sc);
528
529 if (!rq || !scsi_prot_sg_count(sc))
530 return;
531
532 bi = blk_get_integrity(rq->rq_disk);
533
534 if (sc->sc_data_direction == DMA_TO_DEVICE)
535 cmd_pi->pi_bytesout = cpu_to_virtio32(vdev,
536 bio_integrity_bytes(bi,
537 blk_rq_sectors(rq)));
538 else if (sc->sc_data_direction == DMA_FROM_DEVICE)
539 cmd_pi->pi_bytesin = cpu_to_virtio32(vdev,
540 bio_integrity_bytes(bi,
541 blk_rq_sectors(rq)));
542 }
543 #endif
544
545 static struct virtio_scsi_vq *virtscsi_pick_vq_mq(struct virtio_scsi *vscsi,
546 struct scsi_cmnd *sc)
547 {
548 u32 tag = blk_mq_unique_tag(sc->request);
549 u16 hwq = blk_mq_unique_tag_to_hwq(tag);
550
551 return &vscsi->req_vqs[hwq];
552 }
553
554 static int virtscsi_queuecommand(struct Scsi_Host *shost,
555 struct scsi_cmnd *sc)
556 {
557 struct virtio_scsi *vscsi = shost_priv(shost);
558 struct virtio_scsi_vq *req_vq = virtscsi_pick_vq_mq(vscsi, sc);
559 struct virtio_scsi_cmd *cmd = scsi_cmd_priv(sc);
560 bool kick;
561 unsigned long flags;
562 int req_size;
563 int ret;
564
565 BUG_ON(scsi_sg_count(sc) > shost->sg_tablesize);
566
567 /* TODO: check feature bit and fail if unsupported? */
568 BUG_ON(sc->sc_data_direction == DMA_BIDIRECTIONAL);
569
570 dev_dbg(&sc->device->sdev_gendev,
571 "cmd %p CDB: %#02x\n", sc, sc->cmnd[0]);
572
573 cmd->sc = sc;
574
575 BUG_ON(sc->cmd_len > VIRTIO_SCSI_CDB_SIZE);
576
577 #ifdef CONFIG_BLK_DEV_INTEGRITY
578 if (virtio_has_feature(vscsi->vdev, VIRTIO_SCSI_F_T10_PI)) {
579 virtio_scsi_init_hdr_pi(vscsi->vdev, &cmd->req.cmd_pi, sc);
580 memcpy(cmd->req.cmd_pi.cdb, sc->cmnd, sc->cmd_len);
581 req_size = sizeof(cmd->req.cmd_pi);
582 } else
583 #endif
584 {
585 virtio_scsi_init_hdr(vscsi->vdev, &cmd->req.cmd, sc);
586 memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);
587 req_size = sizeof(cmd->req.cmd);
588 }
589
590 kick = (sc->flags & SCMD_LAST) != 0;
591 ret = virtscsi_add_cmd(req_vq, cmd, req_size, sizeof(cmd->resp.cmd), kick);
592 if (ret == -EIO) {
593 cmd->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET;
594 spin_lock_irqsave(&req_vq->vq_lock, flags);
595 virtscsi_complete_cmd(vscsi, cmd);
596 spin_unlock_irqrestore(&req_vq->vq_lock, flags);
597 } else if (ret != 0) {
598 return SCSI_MLQUEUE_HOST_BUSY;
599 }
600 return 0;
601 }
602
603 static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd)
604 {
605 DECLARE_COMPLETION_ONSTACK(comp);
606 int ret = FAILED;
607
608 cmd->comp = &comp;
609 if (virtscsi_add_cmd(&vscsi->ctrl_vq, cmd,
610 sizeof cmd->req.tmf, sizeof cmd->resp.tmf, true) < 0)
611 goto out;
612
613 wait_for_completion(&comp);
614 if (cmd->resp.tmf.response == VIRTIO_SCSI_S_OK ||
615 cmd->resp.tmf.response == VIRTIO_SCSI_S_FUNCTION_SUCCEEDED)
616 ret = SUCCESS;
617
618 /*
619 * The spec guarantees that all requests related to the TMF have
620 * been completed, but the callback might not have run yet if
621 * we're using independent interrupts (e.g. MSI). Poll the
622 * virtqueues once.
623 *
624 * In the abort case, sc->scsi_done will do nothing, because
625 * the block layer must have detected a timeout and as a result
626 * REQ_ATOM_COMPLETE has been set.
627 */
628 virtscsi_poll_requests(vscsi);
629
630 out:
631 mempool_free(cmd, virtscsi_cmd_pool);
632 return ret;
633 }
634
635 static int virtscsi_device_reset(struct scsi_cmnd *sc)
636 {
637 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
638 struct virtio_scsi_cmd *cmd;
639
640 sdev_printk(KERN_INFO, sc->device, "device reset\n");
641 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
642 if (!cmd)
643 return FAILED;
644
645 memset(cmd, 0, sizeof(*cmd));
646 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
647 .type = VIRTIO_SCSI_T_TMF,
648 .subtype = cpu_to_virtio32(vscsi->vdev,
649 VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET),
650 .lun[0] = 1,
651 .lun[1] = sc->device->id,
652 .lun[2] = (sc->device->lun >> 8) | 0x40,
653 .lun[3] = sc->device->lun & 0xff,
654 };
655 return virtscsi_tmf(vscsi, cmd);
656 }
657
658 static int virtscsi_device_alloc(struct scsi_device *sdevice)
659 {
660 /*
661 * Passed through SCSI targets (e.g. with qemu's 'scsi-block')
662 * may have transfer limits which come from the host SCSI
663 * controller or something on the host side other than the
664 * target itself.
665 *
666 * To make this work properly, the hypervisor can adjust the
667 * target's VPD information to advertise these limits. But
668 * for that to work, the guest has to look at the VPD pages,
669 * which we won't do by default if it is an SPC-2 device, even
670 * if it does actually support it.
671 *
672 * So, set the blist to always try to read the VPD pages.
673 */
674 sdevice->sdev_bflags = BLIST_TRY_VPD_PAGES;
675
676 return 0;
677 }
678
679
680 /**
681 * virtscsi_change_queue_depth() - Change a virtscsi target's queue depth
682 * @sdev: Virtscsi target whose queue depth to change
683 * @qdepth: New queue depth
684 */
685 static int virtscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
686 {
687 struct Scsi_Host *shost = sdev->host;
688 int max_depth = shost->cmd_per_lun;
689
690 return scsi_change_queue_depth(sdev, min(max_depth, qdepth));
691 }
692
693 static int virtscsi_abort(struct scsi_cmnd *sc)
694 {
695 struct virtio_scsi *vscsi = shost_priv(sc->device->host);
696 struct virtio_scsi_cmd *cmd;
697
698 scmd_printk(KERN_INFO, sc, "abort\n");
699 cmd = mempool_alloc(virtscsi_cmd_pool, GFP_NOIO);
700 if (!cmd)
701 return FAILED;
702
703 memset(cmd, 0, sizeof(*cmd));
704 cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){
705 .type = VIRTIO_SCSI_T_TMF,
706 .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,
707 .lun[0] = 1,
708 .lun[1] = sc->device->id,
709 .lun[2] = (sc->device->lun >> 8) | 0x40,
710 .lun[3] = sc->device->lun & 0xff,
711 .tag = cpu_to_virtio64(vscsi->vdev, (unsigned long)sc),
712 };
713 return virtscsi_tmf(vscsi, cmd);
714 }
715
716 static int virtscsi_map_queues(struct Scsi_Host *shost)
717 {
718 struct virtio_scsi *vscsi = shost_priv(shost);
719 struct blk_mq_queue_map *qmap = &shost->tag_set.map[HCTX_TYPE_DEFAULT];
720
721 return blk_mq_virtio_map_queues(qmap, vscsi->vdev, 2);
722 }
723
724 static void virtscsi_commit_rqs(struct Scsi_Host *shost, u16 hwq)
725 {
726 struct virtio_scsi *vscsi = shost_priv(shost);
727
728 virtscsi_kick_vq(&vscsi->req_vqs[hwq]);
729 }
730
731 /*
732 * The host guarantees to respond to each command, although I/O
733 * latencies might be higher than on bare metal. Reset the timer
734 * unconditionally to give the host a chance to perform EH.
735 */
736 static enum blk_eh_timer_return virtscsi_eh_timed_out(struct scsi_cmnd *scmnd)
737 {
738 return BLK_EH_RESET_TIMER;
739 }
740
741 static struct scsi_host_template virtscsi_host_template = {
742 .module = THIS_MODULE,
743 .name = "Virtio SCSI HBA",
744 .proc_name = "virtio_scsi",
745 .this_id = -1,
746 .cmd_size = sizeof(struct virtio_scsi_cmd),
747 .queuecommand = virtscsi_queuecommand,
748 .commit_rqs = virtscsi_commit_rqs,
749 .change_queue_depth = virtscsi_change_queue_depth,
750 .eh_abort_handler = virtscsi_abort,
751 .eh_device_reset_handler = virtscsi_device_reset,
752 .eh_timed_out = virtscsi_eh_timed_out,
753 .slave_alloc = virtscsi_device_alloc,
754
755 .dma_boundary = UINT_MAX,
756 .map_queues = virtscsi_map_queues,
757 .track_queue_depth = 1,
758 };
759
760 #define virtscsi_config_get(vdev, fld) \
761 ({ \
762 __virtio_native_type(struct virtio_scsi_config, fld) __val; \
763 virtio_cread(vdev, struct virtio_scsi_config, fld, &__val); \
764 __val; \
765 })
766
767 #define virtscsi_config_set(vdev, fld, val) \
768 do { \
769 __virtio_native_type(struct virtio_scsi_config, fld) __val = (val); \
770 virtio_cwrite(vdev, struct virtio_scsi_config, fld, &__val); \
771 } while(0)
772
773 static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
774 struct virtqueue *vq)
775 {
776 spin_lock_init(&virtscsi_vq->vq_lock);
777 virtscsi_vq->vq = vq;
778 }
779
780 static void virtscsi_remove_vqs(struct virtio_device *vdev)
781 {
782 /* Stop all the virtqueues. */
783 vdev->config->reset(vdev);
784 vdev->config->del_vqs(vdev);
785 }
786
787 static int virtscsi_init(struct virtio_device *vdev,
788 struct virtio_scsi *vscsi)
789 {
790 int err;
791 u32 i;
792 u32 num_vqs;
793 vq_callback_t **callbacks;
794 const char **names;
795 struct virtqueue **vqs;
796 struct irq_affinity desc = { .pre_vectors = 2 };
797
798 num_vqs = vscsi->num_queues + VIRTIO_SCSI_VQ_BASE;
799 vqs = kmalloc_array(num_vqs, sizeof(struct virtqueue *), GFP_KERNEL);
800 callbacks = kmalloc_array(num_vqs, sizeof(vq_callback_t *),
801 GFP_KERNEL);
802 names = kmalloc_array(num_vqs, sizeof(char *), GFP_KERNEL);
803
804 if (!callbacks || !vqs || !names) {
805 err = -ENOMEM;
806 goto out;
807 }
808
809 callbacks[0] = virtscsi_ctrl_done;
810 callbacks[1] = virtscsi_event_done;
811 names[0] = "control";
812 names[1] = "event";
813 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++) {
814 callbacks[i] = virtscsi_req_done;
815 names[i] = "request";
816 }
817
818 /* Discover virtqueues and write information to configuration. */
819 err = virtio_find_vqs(vdev, num_vqs, vqs, callbacks, names, &desc);
820 if (err)
821 goto out;
822
823 virtscsi_init_vq(&vscsi->ctrl_vq, vqs[0]);
824 virtscsi_init_vq(&vscsi->event_vq, vqs[1]);
825 for (i = VIRTIO_SCSI_VQ_BASE; i < num_vqs; i++)
826 virtscsi_init_vq(&vscsi->req_vqs[i - VIRTIO_SCSI_VQ_BASE],
827 vqs[i]);
828
829 virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
830 virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
831
832 err = 0;
833
834 out:
835 kfree(names);
836 kfree(callbacks);
837 kfree(vqs);
838 if (err)
839 virtscsi_remove_vqs(vdev);
840 return err;
841 }
842
843 static int virtscsi_probe(struct virtio_device *vdev)
844 {
845 struct Scsi_Host *shost;
846 struct virtio_scsi *vscsi;
847 int err;
848 u32 sg_elems, num_targets;
849 u32 cmd_per_lun;
850 u32 num_queues;
851
852 if (!vdev->config->get) {
853 dev_err(&vdev->dev, "%s failure: config access disabled\n",
854 __func__);
855 return -EINVAL;
856 }
857
858 /* We need to know how many queues before we allocate. */
859 num_queues = virtscsi_config_get(vdev, num_queues) ? : 1;
860 num_queues = min_t(unsigned int, nr_cpu_ids, num_queues);
861
862 num_targets = virtscsi_config_get(vdev, max_target) + 1;
863
864 shost = scsi_host_alloc(&virtscsi_host_template,
865 struct_size(vscsi, req_vqs, num_queues));
866 if (!shost)
867 return -ENOMEM;
868
869 sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
870 shost->sg_tablesize = sg_elems;
871 vscsi = shost_priv(shost);
872 vscsi->vdev = vdev;
873 vscsi->num_queues = num_queues;
874 vdev->priv = shost;
875
876 err = virtscsi_init(vdev, vscsi);
877 if (err)
878 goto virtscsi_init_failed;
879
880 shost->can_queue = virtqueue_get_vring_size(vscsi->req_vqs[0].vq);
881
882 cmd_per_lun = virtscsi_config_get(vdev, cmd_per_lun) ?: 1;
883 shost->cmd_per_lun = min_t(u32, cmd_per_lun, shost->can_queue);
884 shost->max_sectors = virtscsi_config_get(vdev, max_sectors) ?: 0xFFFF;
885
886 /* LUNs > 256 are reported with format 1, so they go in the range
887 * 16640-32767.
888 */
889 shost->max_lun = virtscsi_config_get(vdev, max_lun) + 1 + 0x4000;
890 shost->max_id = num_targets;
891 shost->max_channel = 0;
892 shost->max_cmd_len = VIRTIO_SCSI_CDB_SIZE;
893 shost->nr_hw_queues = num_queues;
894
895 #ifdef CONFIG_BLK_DEV_INTEGRITY
896 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_T10_PI)) {
897 int host_prot;
898
899 host_prot = SHOST_DIF_TYPE1_PROTECTION | SHOST_DIF_TYPE2_PROTECTION |
900 SHOST_DIF_TYPE3_PROTECTION | SHOST_DIX_TYPE1_PROTECTION |
901 SHOST_DIX_TYPE2_PROTECTION | SHOST_DIX_TYPE3_PROTECTION;
902
903 scsi_host_set_prot(shost, host_prot);
904 scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC);
905 }
906 #endif
907
908 err = scsi_add_host(shost, &vdev->dev);
909 if (err)
910 goto scsi_add_host_failed;
911
912 virtio_device_ready(vdev);
913
914 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
915 virtscsi_kick_event_all(vscsi);
916
917 scsi_scan_host(shost);
918 return 0;
919
920 scsi_add_host_failed:
921 vdev->config->del_vqs(vdev);
922 virtscsi_init_failed:
923 scsi_host_put(shost);
924 return err;
925 }
926
927 static void virtscsi_remove(struct virtio_device *vdev)
928 {
929 struct Scsi_Host *shost = virtio_scsi_host(vdev);
930 struct virtio_scsi *vscsi = shost_priv(shost);
931
932 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
933 virtscsi_cancel_event_work(vscsi);
934
935 scsi_remove_host(shost);
936 virtscsi_remove_vqs(vdev);
937 scsi_host_put(shost);
938 }
939
940 #ifdef CONFIG_PM_SLEEP
941 static int virtscsi_freeze(struct virtio_device *vdev)
942 {
943 virtscsi_remove_vqs(vdev);
944 return 0;
945 }
946
947 static int virtscsi_restore(struct virtio_device *vdev)
948 {
949 struct Scsi_Host *sh = virtio_scsi_host(vdev);
950 struct virtio_scsi *vscsi = shost_priv(sh);
951 int err;
952
953 err = virtscsi_init(vdev, vscsi);
954 if (err)
955 return err;
956
957 virtio_device_ready(vdev);
958
959 if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
960 virtscsi_kick_event_all(vscsi);
961
962 return err;
963 }
964 #endif
965
966 static struct virtio_device_id id_table[] = {
967 { VIRTIO_ID_SCSI, VIRTIO_DEV_ANY_ID },
968 { 0 },
969 };
970
971 static unsigned int features[] = {
972 VIRTIO_SCSI_F_HOTPLUG,
973 VIRTIO_SCSI_F_CHANGE,
974 #ifdef CONFIG_BLK_DEV_INTEGRITY
975 VIRTIO_SCSI_F_T10_PI,
976 #endif
977 };
978
979 static struct virtio_driver virtio_scsi_driver = {
980 .feature_table = features,
981 .feature_table_size = ARRAY_SIZE(features),
982 .driver.name = KBUILD_MODNAME,
983 .driver.owner = THIS_MODULE,
984 .id_table = id_table,
985 .probe = virtscsi_probe,
986 #ifdef CONFIG_PM_SLEEP
987 .freeze = virtscsi_freeze,
988 .restore = virtscsi_restore,
989 #endif
990 .remove = virtscsi_remove,
991 };
992
993 static int __init init(void)
994 {
995 int ret = -ENOMEM;
996
997 virtscsi_cmd_cache = KMEM_CACHE(virtio_scsi_cmd, 0);
998 if (!virtscsi_cmd_cache) {
999 pr_err("kmem_cache_create() for virtscsi_cmd_cache failed\n");
1000 goto error;
1001 }
1002
1003
1004 virtscsi_cmd_pool =
1005 mempool_create_slab_pool(VIRTIO_SCSI_MEMPOOL_SZ,
1006 virtscsi_cmd_cache);
1007 if (!virtscsi_cmd_pool) {
1008 pr_err("mempool_create() for virtscsi_cmd_pool failed\n");
1009 goto error;
1010 }
1011 ret = register_virtio_driver(&virtio_scsi_driver);
1012 if (ret < 0)
1013 goto error;
1014
1015 return 0;
1016
1017 error:
1018 mempool_destroy(virtscsi_cmd_pool);
1019 virtscsi_cmd_pool = NULL;
1020 kmem_cache_destroy(virtscsi_cmd_cache);
1021 virtscsi_cmd_cache = NULL;
1022 return ret;
1023 }
1024
1025 static void __exit fini(void)
1026 {
1027 unregister_virtio_driver(&virtio_scsi_driver);
1028 mempool_destroy(virtscsi_cmd_pool);
1029 kmem_cache_destroy(virtscsi_cmd_cache);
1030 }
1031 module_init(init);
1032 module_exit(fini);
1033
1034 MODULE_DEVICE_TABLE(virtio, id_table);
1035 MODULE_DESCRIPTION("Virtio SCSI HBA driver");
1036 MODULE_LICENSE("GPL");
Linux with added FPC-III support