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14#include "qemu/osdep.h"
15#include "qapi/error.h"
16#include "qemu/iov.h"
17#include "qemu/module.h"
18#include "qemu/error-report.h"
19#include "qemu/main-loop.h"
20#include "trace.h"
21#include "hw/block/block.h"
22#include "hw/qdev-properties.h"
23#include "sysemu/blockdev.h"
24#include "sysemu/sysemu.h"
25#include "sysemu/runstate.h"
26#include "hw/virtio/virtio-blk.h"
27#include "dataplane/virtio-blk.h"
28#include "scsi/constants.h"
29#ifdef __linux__
30# include <scsi/sg.h>
31#endif
32#include "hw/virtio/virtio-bus.h"
33#include "migration/qemu-file-types.h"
34#include "hw/virtio/virtio-access.h"
35
36
37#define VIRTIO_BLK_CFG_SIZE offsetof(struct virtio_blk_config, \
38 max_discard_sectors)
39
40
41
42
43static VirtIOFeature feature_sizes[] = {
44 {.flags = 1ULL << VIRTIO_BLK_F_DISCARD,
45 .end = endof(struct virtio_blk_config, discard_sector_alignment)},
46 {.flags = 1ULL << VIRTIO_BLK_F_WRITE_ZEROES,
47 .end = endof(struct virtio_blk_config, write_zeroes_may_unmap)},
48 {}
49};
50
51static void virtio_blk_set_config_size(VirtIOBlock *s, uint64_t host_features)
52{
53 s->config_size = MAX(VIRTIO_BLK_CFG_SIZE,
54 virtio_feature_get_config_size(feature_sizes, host_features));
55
56 assert(s->config_size <= sizeof(struct virtio_blk_config));
57}
58
59static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
60 VirtIOBlockReq *req)
61{
62 req->dev = s;
63 req->vq = vq;
64 req->qiov.size = 0;
65 req->in_len = 0;
66 req->next = NULL;
67 req->mr_next = NULL;
68}
69
70static void virtio_blk_free_request(VirtIOBlockReq *req)
71{
72 g_free(req);
73}
74
75static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status)
76{
77 VirtIOBlock *s = req->dev;
78 VirtIODevice *vdev = VIRTIO_DEVICE(s);
79
80 trace_virtio_blk_req_complete(vdev, req, status);
81
82 stb_p(&req->in->status, status);
83 virtqueue_push(req->vq, &req->elem, req->in_len);
84 if (s->dataplane_started && !s->dataplane_disabled) {
85 virtio_blk_data_plane_notify(s->dataplane, req->vq);
86 } else {
87 virtio_notify(vdev, req->vq);
88 }
89}
90
91static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error,
92 bool is_read, bool acct_failed)
93{
94 VirtIOBlock *s = req->dev;
95 BlockErrorAction action = blk_get_error_action(s->blk, is_read, error);
96
97 if (action == BLOCK_ERROR_ACTION_STOP) {
98
99
100 req->mr_next = NULL;
101 req->next = s->rq;
102 s->rq = req;
103 } else if (action == BLOCK_ERROR_ACTION_REPORT) {
104 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
105 if (acct_failed) {
106 block_acct_failed(blk_get_stats(s->blk), &req->acct);
107 }
108 virtio_blk_free_request(req);
109 }
110
111 blk_error_action(s->blk, action, is_read, error);
112 return action != BLOCK_ERROR_ACTION_IGNORE;
113}
114
115static void virtio_blk_rw_complete(void *opaque, int ret)
116{
117 VirtIOBlockReq *next = opaque;
118 VirtIOBlock *s = next->dev;
119 VirtIODevice *vdev = VIRTIO_DEVICE(s);
120
121 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
122 while (next) {
123 VirtIOBlockReq *req = next;
124 next = req->mr_next;
125 trace_virtio_blk_rw_complete(vdev, req, ret);
126
127 if (req->qiov.nalloc != -1) {
128
129
130
131 qemu_iovec_destroy(&req->qiov);
132 }
133
134 if (ret) {
135 int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type);
136 bool is_read = !(p & VIRTIO_BLK_T_OUT);
137
138
139
140
141
142
143
144
145 if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) {
146 continue;
147 }
148 }
149
150 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
151 block_acct_done(blk_get_stats(s->blk), &req->acct);
152 virtio_blk_free_request(req);
153 }
154 aio_context_release(blk_get_aio_context(s->conf.conf.blk));
155}
156
157static void virtio_blk_flush_complete(void *opaque, int ret)
158{
159 VirtIOBlockReq *req = opaque;
160 VirtIOBlock *s = req->dev;
161
162 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
163 if (ret) {
164 if (virtio_blk_handle_rw_error(req, -ret, 0, true)) {
165 goto out;
166 }
167 }
168
169 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
170 block_acct_done(blk_get_stats(s->blk), &req->acct);
171 virtio_blk_free_request(req);
172
173out:
174 aio_context_release(blk_get_aio_context(s->conf.conf.blk));
175}
176
177static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret)
178{
179 VirtIOBlockReq *req = opaque;
180 VirtIOBlock *s = req->dev;
181 bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) &
182 ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES;
183
184 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
185 if (ret) {
186 if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) {
187 goto out;
188 }
189 }
190
191 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
192 if (is_write_zeroes) {
193 block_acct_done(blk_get_stats(s->blk), &req->acct);
194 }
195 virtio_blk_free_request(req);
196
197out:
198 aio_context_release(blk_get_aio_context(s->conf.conf.blk));
199}
200
201#ifdef __linux__
202
203typedef struct {
204 VirtIOBlockReq *req;
205 struct sg_io_hdr hdr;
206} VirtIOBlockIoctlReq;
207
208static void virtio_blk_ioctl_complete(void *opaque, int status)
209{
210 VirtIOBlockIoctlReq *ioctl_req = opaque;
211 VirtIOBlockReq *req = ioctl_req->req;
212 VirtIOBlock *s = req->dev;
213 VirtIODevice *vdev = VIRTIO_DEVICE(s);
214 struct virtio_scsi_inhdr *scsi;
215 struct sg_io_hdr *hdr;
216
217 scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base;
218
219 if (status) {
220 status = VIRTIO_BLK_S_UNSUPP;
221 virtio_stl_p(vdev, &scsi->errors, 255);
222 goto out;
223 }
224
225 hdr = &ioctl_req->hdr;
226
227
228
229
230
231
232
233 if (hdr->status == 0 && hdr->sb_len_wr > 0) {
234 hdr->status = CHECK_CONDITION;
235 }
236
237 virtio_stl_p(vdev, &scsi->errors,
238 hdr->status | (hdr->msg_status << 8) |
239 (hdr->host_status << 16) | (hdr->driver_status << 24));
240 virtio_stl_p(vdev, &scsi->residual, hdr->resid);
241 virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr);
242 virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len);
243
244out:
245 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
246 virtio_blk_req_complete(req, status);
247 virtio_blk_free_request(req);
248 aio_context_release(blk_get_aio_context(s->conf.conf.blk));
249 g_free(ioctl_req);
250}
251
252#endif
253
254static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq)
255{
256 VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq));
257
258 if (req) {
259 virtio_blk_init_request(s, vq, req);
260 }
261 return req;
262}
263
264static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
265{
266 int status = VIRTIO_BLK_S_OK;
267 struct virtio_scsi_inhdr *scsi = NULL;
268 VirtIOBlock *blk = req->dev;
269 VirtIODevice *vdev = VIRTIO_DEVICE(blk);
270 VirtQueueElement *elem = &req->elem;
271
272#ifdef __linux__
273 int i;
274 VirtIOBlockIoctlReq *ioctl_req;
275 BlockAIOCB *acb;
276#endif
277
278
279
280
281
282
283
284
285 if (elem->out_num < 2 || elem->in_num < 3) {
286 status = VIRTIO_BLK_S_IOERR;
287 goto fail;
288 }
289
290
291
292
293
294 scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base;
295
296 if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) {
297 status = VIRTIO_BLK_S_UNSUPP;
298 goto fail;
299 }
300
301
302
303
304 if (elem->out_num > 2 && elem->in_num > 3) {
305 status = VIRTIO_BLK_S_UNSUPP;
306 goto fail;
307 }
308
309#ifdef __linux__
310 ioctl_req = g_new0(VirtIOBlockIoctlReq, 1);
311 ioctl_req->req = req;
312 ioctl_req->hdr.interface_id = 'S';
313 ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len;
314 ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base;
315 ioctl_req->hdr.dxfer_len = 0;
316
317 if (elem->out_num > 2) {
318
319
320
321
322 ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV;
323 ioctl_req->hdr.iovec_count = elem->out_num - 2;
324
325 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
326 ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len;
327 }
328
329 ioctl_req->hdr.dxferp = elem->out_sg + 2;
330
331 } else if (elem->in_num > 3) {
332
333
334
335
336 ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV;
337 ioctl_req->hdr.iovec_count = elem->in_num - 3;
338 for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
339 ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len;
340 }
341
342 ioctl_req->hdr.dxferp = elem->in_sg;
343 } else {
344
345
346
347 ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE;
348 }
349
350 ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base;
351 ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len;
352
353 acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
354 virtio_blk_ioctl_complete, ioctl_req);
355 if (!acb) {
356 g_free(ioctl_req);
357 status = VIRTIO_BLK_S_UNSUPP;
358 goto fail;
359 }
360 return -EINPROGRESS;
361#else
362 abort();
363#endif
364
365fail:
366
367 if (scsi) {
368 virtio_stl_p(vdev, &scsi->errors, 255);
369 }
370 return status;
371}
372
373static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
374{
375 int status;
376
377 status = virtio_blk_handle_scsi_req(req);
378 if (status != -EINPROGRESS) {
379 virtio_blk_req_complete(req, status);
380 virtio_blk_free_request(req);
381 }
382}
383
384static inline void submit_requests(BlockBackend *blk, MultiReqBuffer *mrb,
385 int start, int num_reqs, int niov)
386{
387 QEMUIOVector *qiov = &mrb->reqs[start]->qiov;
388 int64_t sector_num = mrb->reqs[start]->sector_num;
389 bool is_write = mrb->is_write;
390
391 if (num_reqs > 1) {
392 int i;
393 struct iovec *tmp_iov = qiov->iov;
394 int tmp_niov = qiov->niov;
395
396
397
398
399 qemu_iovec_init(qiov, niov);
400
401 for (i = 0; i < tmp_niov; i++) {
402 qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len);
403 }
404
405 for (i = start + 1; i < start + num_reqs; i++) {
406 qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0,
407 mrb->reqs[i]->qiov.size);
408 mrb->reqs[i - 1]->mr_next = mrb->reqs[i];
409 }
410
411 trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev),
412 mrb, start, num_reqs,
413 sector_num << BDRV_SECTOR_BITS,
414 qiov->size, is_write);
415 block_acct_merge_done(blk_get_stats(blk),
416 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ,
417 num_reqs - 1);
418 }
419
420 if (is_write) {
421 blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0,
422 virtio_blk_rw_complete, mrb->reqs[start]);
423 } else {
424 blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov, 0,
425 virtio_blk_rw_complete, mrb->reqs[start]);
426 }
427}
428
429static int multireq_compare(const void *a, const void *b)
430{
431 const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a,
432 *req2 = *(VirtIOBlockReq **)b;
433
434
435
436
437
438 if (req1->sector_num > req2->sector_num) {
439 return 1;
440 } else if (req1->sector_num < req2->sector_num) {
441 return -1;
442 } else {
443 return 0;
444 }
445}
446
447static void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb)
448{
449 int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0;
450 uint32_t max_transfer;
451 int64_t sector_num = 0;
452
453 if (mrb->num_reqs == 1) {
454 submit_requests(blk, mrb, 0, 1, -1);
455 mrb->num_reqs = 0;
456 return;
457 }
458
459 max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk);
460
461 qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),
462 &multireq_compare);
463
464 for (i = 0; i < mrb->num_reqs; i++) {
465 VirtIOBlockReq *req = mrb->reqs[i];
466 if (num_reqs > 0) {
467
468
469
470
471
472
473 if (sector_num + nb_sectors != req->sector_num ||
474 niov > blk_get_max_iov(blk) - req->qiov.niov ||
475 req->qiov.size > max_transfer ||
476 nb_sectors > (max_transfer -
477 req->qiov.size) / BDRV_SECTOR_SIZE) {
478 submit_requests(blk, mrb, start, num_reqs, niov);
479 num_reqs = 0;
480 }
481 }
482
483 if (num_reqs == 0) {
484 sector_num = req->sector_num;
485 nb_sectors = niov = 0;
486 start = i;
487 }
488
489 nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE;
490 niov += req->qiov.niov;
491 num_reqs++;
492 }
493
494 submit_requests(blk, mrb, start, num_reqs, niov);
495 mrb->num_reqs = 0;
496}
497
498static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
499{
500 VirtIOBlock *s = req->dev;
501
502 block_acct_start(blk_get_stats(s->blk), &req->acct, 0,
503 BLOCK_ACCT_FLUSH);
504
505
506
507
508 if (mrb->is_write && mrb->num_reqs > 0) {
509 virtio_blk_submit_multireq(s->blk, mrb);
510 }
511 blk_aio_flush(s->blk, virtio_blk_flush_complete, req);
512}
513
514static bool virtio_blk_sect_range_ok(VirtIOBlock *dev,
515 uint64_t sector, size_t size)
516{
517 uint64_t nb_sectors = size >> BDRV_SECTOR_BITS;
518 uint64_t total_sectors;
519
520 if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
521 return false;
522 }
523 if (sector & dev->sector_mask) {
524 return false;
525 }
526 if (size % dev->conf.conf.logical_block_size) {
527 return false;
528 }
529 blk_get_geometry(dev->blk, &total_sectors);
530 if (sector > total_sectors || nb_sectors > total_sectors - sector) {
531 return false;
532 }
533 return true;
534}
535
536static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req,
537 struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes)
538{
539 VirtIOBlock *s = req->dev;
540 VirtIODevice *vdev = VIRTIO_DEVICE(s);
541 uint64_t sector;
542 uint32_t num_sectors, flags, max_sectors;
543 uint8_t err_status;
544 int bytes;
545
546 sector = virtio_ldq_p(vdev, &dwz_hdr->sector);
547 num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors);
548 flags = virtio_ldl_p(vdev, &dwz_hdr->flags);
549 max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors :
550 s->conf.max_discard_sectors;
551
552
553
554
555
556
557 if (unlikely(num_sectors > max_sectors)) {
558 err_status = VIRTIO_BLK_S_IOERR;
559 goto err;
560 }
561
562 bytes = num_sectors << BDRV_SECTOR_BITS;
563
564 if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) {
565 err_status = VIRTIO_BLK_S_IOERR;
566 goto err;
567 }
568
569
570
571
572
573 if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
574 err_status = VIRTIO_BLK_S_UNSUPP;
575 goto err;
576 }
577
578 if (is_write_zeroes) {
579 int blk_aio_flags = 0;
580
581 if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
582 blk_aio_flags |= BDRV_REQ_MAY_UNMAP;
583 }
584
585 block_acct_start(blk_get_stats(s->blk), &req->acct, bytes,
586 BLOCK_ACCT_WRITE);
587
588 blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS,
589 bytes, blk_aio_flags,
590 virtio_blk_discard_write_zeroes_complete, req);
591 } else {
592
593
594
595
596 if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
597 err_status = VIRTIO_BLK_S_UNSUPP;
598 goto err;
599 }
600
601 blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes,
602 virtio_blk_discard_write_zeroes_complete, req);
603 }
604
605 return VIRTIO_BLK_S_OK;
606
607err:
608 if (is_write_zeroes) {
609 block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE);
610 }
611 return err_status;
612}
613
614static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
615{
616 uint32_t type;
617 struct iovec *in_iov = req->elem.in_sg;
618 struct iovec *out_iov = req->elem.out_sg;
619 unsigned in_num = req->elem.in_num;
620 unsigned out_num = req->elem.out_num;
621 VirtIOBlock *s = req->dev;
622 VirtIODevice *vdev = VIRTIO_DEVICE(s);
623
624 if (req->elem.out_num < 1 || req->elem.in_num < 1) {
625 virtio_error(vdev, "virtio-blk missing headers");
626 return -1;
627 }
628
629 if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
630 sizeof(req->out)) != sizeof(req->out))) {
631 virtio_error(vdev, "virtio-blk request outhdr too short");
632 return -1;
633 }
634
635 iov_discard_front(&out_iov, &out_num, sizeof(req->out));
636
637 if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
638 virtio_error(vdev, "virtio-blk request inhdr too short");
639 return -1;
640 }
641
642
643 req->in_len = iov_size(in_iov, in_num);
644 req->in = (void *)in_iov[in_num - 1].iov_base
645 + in_iov[in_num - 1].iov_len
646 - sizeof(struct virtio_blk_inhdr);
647 iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr));
648
649 type = virtio_ldl_p(vdev, &req->out.type);
650
651
652
653
654 switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) {
655 case VIRTIO_BLK_T_IN:
656 {
657 bool is_write = type & VIRTIO_BLK_T_OUT;
658 req->sector_num = virtio_ldq_p(vdev, &req->out.sector);
659
660 if (is_write) {
661 qemu_iovec_init_external(&req->qiov, out_iov, out_num);
662 trace_virtio_blk_handle_write(vdev, req, req->sector_num,
663 req->qiov.size / BDRV_SECTOR_SIZE);
664 } else {
665 qemu_iovec_init_external(&req->qiov, in_iov, in_num);
666 trace_virtio_blk_handle_read(vdev, req, req->sector_num,
667 req->qiov.size / BDRV_SECTOR_SIZE);
668 }
669
670 if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) {
671 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
672 block_acct_invalid(blk_get_stats(s->blk),
673 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
674 virtio_blk_free_request(req);
675 return 0;
676 }
677
678 block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size,
679 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
680
681
682
683 if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS ||
684 is_write != mrb->is_write ||
685 !s->conf.request_merging)) {
686 virtio_blk_submit_multireq(s->blk, mrb);
687 }
688
689 assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS);
690 mrb->reqs[mrb->num_reqs++] = req;
691 mrb->is_write = is_write;
692 break;
693 }
694 case VIRTIO_BLK_T_FLUSH:
695 virtio_blk_handle_flush(req, mrb);
696 break;
697 case VIRTIO_BLK_T_SCSI_CMD:
698 virtio_blk_handle_scsi(req);
699 break;
700 case VIRTIO_BLK_T_GET_ID:
701 {
702
703
704
705
706 const char *serial = s->conf.serial ? s->conf.serial : "";
707 size_t size = MIN(strlen(serial) + 1,
708 MIN(iov_size(in_iov, in_num),
709 VIRTIO_BLK_ID_BYTES));
710 iov_from_buf(in_iov, in_num, 0, serial, size);
711 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
712 virtio_blk_free_request(req);
713 break;
714 }
715
716
717
718
719
720 case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT:
721 case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT:
722 {
723 struct virtio_blk_discard_write_zeroes dwz_hdr;
724 size_t out_len = iov_size(out_iov, out_num);
725 bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) ==
726 VIRTIO_BLK_T_WRITE_ZEROES;
727 uint8_t err_status;
728
729
730
731
732
733 if (unlikely(!(type & VIRTIO_BLK_T_OUT) ||
734 out_len > sizeof(dwz_hdr))) {
735 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
736 virtio_blk_free_request(req);
737 return 0;
738 }
739
740 if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr,
741 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) {
742 virtio_error(vdev, "virtio-blk discard/write_zeroes header"
743 " too short");
744 return -1;
745 }
746
747 err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr,
748 is_write_zeroes);
749 if (err_status != VIRTIO_BLK_S_OK) {
750 virtio_blk_req_complete(req, err_status);
751 virtio_blk_free_request(req);
752 }
753
754 break;
755 }
756 default:
757 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
758 virtio_blk_free_request(req);
759 }
760 return 0;
761}
762
763bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq)
764{
765 VirtIOBlockReq *req;
766 MultiReqBuffer mrb = {};
767 bool suppress_notifications = virtio_queue_get_notification(vq);
768 bool progress = false;
769
770 aio_context_acquire(blk_get_aio_context(s->blk));
771 blk_io_plug(s->blk);
772
773 do {
774 if (suppress_notifications) {
775 virtio_queue_set_notification(vq, 0);
776 }
777
778 while ((req = virtio_blk_get_request(s, vq))) {
779 progress = true;
780 if (virtio_blk_handle_request(req, &mrb)) {
781 virtqueue_detach_element(req->vq, &req->elem, 0);
782 virtio_blk_free_request(req);
783 break;
784 }
785 }
786
787 if (suppress_notifications) {
788 virtio_queue_set_notification(vq, 1);
789 }
790 } while (!virtio_queue_empty(vq));
791
792 if (mrb.num_reqs) {
793 virtio_blk_submit_multireq(s->blk, &mrb);
794 }
795
796 blk_io_unplug(s->blk);
797 aio_context_release(blk_get_aio_context(s->blk));
798 return progress;
799}
800
801static void virtio_blk_handle_output_do(VirtIOBlock *s, VirtQueue *vq)
802{
803 virtio_blk_handle_vq(s, vq);
804}
805
806static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
807{
808 VirtIOBlock *s = (VirtIOBlock *)vdev;
809
810 if (s->dataplane) {
811
812
813
814 virtio_device_start_ioeventfd(vdev);
815 if (!s->dataplane_disabled) {
816 return;
817 }
818 }
819 virtio_blk_handle_output_do(s, vq);
820}
821
822void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh)
823{
824 VirtIOBlockReq *req = s->rq;
825 MultiReqBuffer mrb = {};
826
827 s->rq = NULL;
828
829 aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
830 while (req) {
831 VirtIOBlockReq *next = req->next;
832 if (virtio_blk_handle_request(req, &mrb)) {
833
834
835
836 while (req) {
837 next = req->next;
838 virtqueue_detach_element(req->vq, &req->elem, 0);
839 virtio_blk_free_request(req);
840 req = next;
841 }
842 break;
843 }
844 req = next;
845 }
846
847 if (mrb.num_reqs) {
848 virtio_blk_submit_multireq(s->blk, &mrb);
849 }
850 if (is_bh) {
851 blk_dec_in_flight(s->conf.conf.blk);
852 }
853 aio_context_release(blk_get_aio_context(s->conf.conf.blk));
854}
855
856static void virtio_blk_dma_restart_bh(void *opaque)
857{
858 VirtIOBlock *s = opaque;
859
860 qemu_bh_delete(s->bh);
861 s->bh = NULL;
862
863 virtio_blk_process_queued_requests(s, true);
864}
865
866static void virtio_blk_dma_restart_cb(void *opaque, int running,
867 RunState state)
868{
869 VirtIOBlock *s = opaque;
870 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
871 VirtioBusState *bus = VIRTIO_BUS(qbus);
872
873 if (!running) {
874 return;
875 }
876
877
878
879
880
881 if (!s->bh && !virtio_bus_ioeventfd_enabled(bus)) {
882 s->bh = aio_bh_new(blk_get_aio_context(s->conf.conf.blk),
883 virtio_blk_dma_restart_bh, s);
884 blk_inc_in_flight(s->conf.conf.blk);
885 qemu_bh_schedule(s->bh);
886 }
887}
888
889static void virtio_blk_reset(VirtIODevice *vdev)
890{
891 VirtIOBlock *s = VIRTIO_BLK(vdev);
892 AioContext *ctx;
893 VirtIOBlockReq *req;
894
895 ctx = blk_get_aio_context(s->blk);
896 aio_context_acquire(ctx);
897 blk_drain(s->blk);
898
899
900
901 while (s->rq) {
902 req = s->rq;
903 s->rq = req->next;
904 virtqueue_detach_element(req->vq, &req->elem, 0);
905 virtio_blk_free_request(req);
906 }
907
908 aio_context_release(ctx);
909
910 assert(!s->dataplane_started);
911 blk_set_enable_write_cache(s->blk, s->original_wce);
912}
913
914
915
916static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
917{
918 VirtIOBlock *s = VIRTIO_BLK(vdev);
919 BlockConf *conf = &s->conf.conf;
920 struct virtio_blk_config blkcfg;
921 uint64_t capacity;
922 int64_t length;
923 int blk_size = conf->logical_block_size;
924
925 blk_get_geometry(s->blk, &capacity);
926 memset(&blkcfg, 0, sizeof(blkcfg));
927 virtio_stq_p(vdev, &blkcfg.capacity, capacity);
928 virtio_stl_p(vdev, &blkcfg.seg_max,
929 s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2);
930 virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls);
931 virtio_stl_p(vdev, &blkcfg.blk_size, blk_size);
932 virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size);
933 virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
934 blkcfg.geometry.heads = conf->heads;
935
936
937
938
939
940
941
942
943
944
945
946 length = blk_getlength(s->blk);
947 if (length > 0 && length / conf->heads / conf->secs % blk_size) {
948 blkcfg.geometry.sectors = conf->secs & ~s->sector_mask;
949 } else {
950 blkcfg.geometry.sectors = conf->secs;
951 }
952 blkcfg.size_max = 0;
953 blkcfg.physical_block_exp = get_physical_block_exp(conf);
954 blkcfg.alignment_offset = 0;
955 blkcfg.wce = blk_enable_write_cache(s->blk);
956 virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues);
957 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) {
958 virtio_stl_p(vdev, &blkcfg.max_discard_sectors,
959 s->conf.max_discard_sectors);
960 virtio_stl_p(vdev, &blkcfg.discard_sector_alignment,
961 blk_size >> BDRV_SECTOR_BITS);
962
963
964
965
966
967 virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1);
968 }
969 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) {
970 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors,
971 s->conf.max_write_zeroes_sectors);
972 blkcfg.write_zeroes_may_unmap = 1;
973 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1);
974 }
975 memcpy(config, &blkcfg, s->config_size);
976}
977
978static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
979{
980 VirtIOBlock *s = VIRTIO_BLK(vdev);
981 struct virtio_blk_config blkcfg;
982
983 memcpy(&blkcfg, config, s->config_size);
984
985 aio_context_acquire(blk_get_aio_context(s->blk));
986 blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
987 aio_context_release(blk_get_aio_context(s->blk));
988}
989
990static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features,
991 Error **errp)
992{
993 VirtIOBlock *s = VIRTIO_BLK(vdev);
994
995
996 features |= s->host_features;
997
998 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX);
999 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY);
1000 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY);
1001 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE);
1002 if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) {
1003 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) {
1004 error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0");
1005 return 0;
1006 }
1007 } else {
1008 virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT);
1009 virtio_add_feature(&features, VIRTIO_BLK_F_SCSI);
1010 }
1011
1012 if (blk_enable_write_cache(s->blk) ||
1013 (s->conf.x_enable_wce_if_config_wce &&
1014 virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) {
1015 virtio_add_feature(&features, VIRTIO_BLK_F_WCE);
1016 }
1017 if (blk_is_read_only(s->blk)) {
1018 virtio_add_feature(&features, VIRTIO_BLK_F_RO);
1019 }
1020 if (s->conf.num_queues > 1) {
1021 virtio_add_feature(&features, VIRTIO_BLK_F_MQ);
1022 }
1023
1024 return features;
1025}
1026
1027static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
1028{
1029 VirtIOBlock *s = VIRTIO_BLK(vdev);
1030
1031 if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) {
1032 assert(!s->dataplane_started);
1033 }
1034
1035 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
1036 return;
1037 }
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054 if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) {
1055 aio_context_acquire(blk_get_aio_context(s->blk));
1056 blk_set_enable_write_cache(s->blk,
1057 virtio_vdev_has_feature(vdev,
1058 VIRTIO_BLK_F_WCE));
1059 aio_context_release(blk_get_aio_context(s->blk));
1060 }
1061}
1062
1063static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f)
1064{
1065 VirtIOBlock *s = VIRTIO_BLK(vdev);
1066 VirtIOBlockReq *req = s->rq;
1067
1068 while (req) {
1069 qemu_put_sbyte(f, 1);
1070
1071 if (s->conf.num_queues > 1) {
1072 qemu_put_be32(f, virtio_get_queue_index(req->vq));
1073 }
1074
1075 qemu_put_virtqueue_element(vdev, f, &req->elem);
1076 req = req->next;
1077 }
1078 qemu_put_sbyte(f, 0);
1079}
1080
1081static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
1082 int version_id)
1083{
1084 VirtIOBlock *s = VIRTIO_BLK(vdev);
1085
1086 while (qemu_get_sbyte(f)) {
1087 unsigned nvqs = s->conf.num_queues;
1088 unsigned vq_idx = 0;
1089 VirtIOBlockReq *req;
1090
1091 if (nvqs > 1) {
1092 vq_idx = qemu_get_be32(f);
1093
1094 if (vq_idx >= nvqs) {
1095 error_report("Invalid virtqueue index in request list: %#x",
1096 vq_idx);
1097 return -EINVAL;
1098 }
1099 }
1100
1101 req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq));
1102 virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req);
1103 req->next = s->rq;
1104 s->rq = req;
1105 }
1106
1107 return 0;
1108}
1109
1110static void virtio_resize_cb(void *opaque)
1111{
1112 VirtIODevice *vdev = opaque;
1113
1114 assert(qemu_get_current_aio_context() == qemu_get_aio_context());
1115 virtio_notify_config(vdev);
1116}
1117
1118static void virtio_blk_resize(void *opaque)
1119{
1120 VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
1121
1122
1123
1124
1125
1126
1127 aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev);
1128}
1129
1130static const BlockDevOps virtio_block_ops = {
1131 .resize_cb = virtio_blk_resize,
1132};
1133
1134static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
1135{
1136 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1137 VirtIOBlock *s = VIRTIO_BLK(dev);
1138 VirtIOBlkConf *conf = &s->conf;
1139 Error *err = NULL;
1140 unsigned i;
1141
1142 if (!conf->conf.blk) {
1143 error_setg(errp, "drive property not set");
1144 return;
1145 }
1146 if (!blk_is_inserted(conf->conf.blk)) {
1147 error_setg(errp, "Device needs media, but drive is empty");
1148 return;
1149 }
1150 if (!conf->num_queues) {
1151 error_setg(errp, "num-queues property must be larger than 0");
1152 return;
1153 }
1154 if (conf->queue_size <= 2) {
1155 error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1156 "must be > 2", conf->queue_size);
1157 return;
1158 }
1159 if (!is_power_of_2(conf->queue_size) ||
1160 conf->queue_size > VIRTQUEUE_MAX_SIZE) {
1161 error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1162 "must be a power of 2 (max %d)",
1163 conf->queue_size, VIRTQUEUE_MAX_SIZE);
1164 return;
1165 }
1166
1167 if (!blkconf_apply_backend_options(&conf->conf,
1168 blk_is_read_only(conf->conf.blk), true,
1169 errp)) {
1170 return;
1171 }
1172 s->original_wce = blk_enable_write_cache(conf->conf.blk);
1173 if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) {
1174 return;
1175 }
1176
1177 if (!blkconf_blocksizes(&conf->conf, errp)) {
1178 return;
1179 }
1180
1181 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) &&
1182 (!conf->max_discard_sectors ||
1183 conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1184 error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")"
1185 ", must be between 1 and %d",
1186 conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS);
1187 return;
1188 }
1189
1190 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) &&
1191 (!conf->max_write_zeroes_sectors ||
1192 conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1193 error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32
1194 "), must be between 1 and %d",
1195 conf->max_write_zeroes_sectors,
1196 (int)BDRV_REQUEST_MAX_SECTORS);
1197 return;
1198 }
1199
1200 virtio_blk_set_config_size(s, s->host_features);
1201
1202 virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size);
1203
1204 s->blk = conf->conf.blk;
1205 s->rq = NULL;
1206 s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1;
1207
1208 for (i = 0; i < conf->num_queues; i++) {
1209 virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output);
1210 }
1211 virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err);
1212 if (err != NULL) {
1213 error_propagate(errp, err);
1214 for (i = 0; i < conf->num_queues; i++) {
1215 virtio_del_queue(vdev, i);
1216 }
1217 virtio_cleanup(vdev);
1218 return;
1219 }
1220
1221 s->change = qemu_add_vm_change_state_handler(virtio_blk_dma_restart_cb, s);
1222 blk_set_dev_ops(s->blk, &virtio_block_ops, s);
1223 blk_set_guest_block_size(s->blk, s->conf.conf.logical_block_size);
1224
1225 blk_iostatus_enable(s->blk);
1226
1227 add_boot_device_lchs(dev, "/disk@0,0",
1228 conf->conf.lcyls,
1229 conf->conf.lheads,
1230 conf->conf.lsecs);
1231}
1232
1233static void virtio_blk_device_unrealize(DeviceState *dev)
1234{
1235 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1236 VirtIOBlock *s = VIRTIO_BLK(dev);
1237 VirtIOBlkConf *conf = &s->conf;
1238 unsigned i;
1239
1240 blk_drain(s->blk);
1241 del_boot_device_lchs(dev, "/disk@0,0");
1242 virtio_blk_data_plane_destroy(s->dataplane);
1243 s->dataplane = NULL;
1244 for (i = 0; i < conf->num_queues; i++) {
1245 virtio_del_queue(vdev, i);
1246 }
1247 qemu_del_vm_change_state_handler(s->change);
1248 blockdev_mark_auto_del(s->blk);
1249 virtio_cleanup(vdev);
1250}
1251
1252static void virtio_blk_instance_init(Object *obj)
1253{
1254 VirtIOBlock *s = VIRTIO_BLK(obj);
1255
1256 device_add_bootindex_property(obj, &s->conf.conf.bootindex,
1257 "bootindex", "/disk@0,0",
1258 DEVICE(obj));
1259}
1260
1261static const VMStateDescription vmstate_virtio_blk = {
1262 .name = "virtio-blk",
1263 .minimum_version_id = 2,
1264 .version_id = 2,
1265 .fields = (VMStateField[]) {
1266 VMSTATE_VIRTIO_DEVICE,
1267 VMSTATE_END_OF_LIST()
1268 },
1269};
1270
1271static Property virtio_blk_properties[] = {
1272 DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf),
1273 DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf),
1274 DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf),
1275 DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial),
1276 DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features,
1277 VIRTIO_BLK_F_CONFIG_WCE, true),
1278#ifdef __linux__
1279 DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features,
1280 VIRTIO_BLK_F_SCSI, false),
1281#endif
1282 DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
1283 true),
1284 DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues, 1),
1285 DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256),
1286 DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true),
1287 DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD,
1288 IOThread *),
1289 DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features,
1290 VIRTIO_BLK_F_DISCARD, true),
1291 DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features,
1292 VIRTIO_BLK_F_WRITE_ZEROES, true),
1293 DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock,
1294 conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS),
1295 DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock,
1296 conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS),
1297 DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock,
1298 conf.x_enable_wce_if_config_wce, true),
1299 DEFINE_PROP_END_OF_LIST(),
1300};
1301
1302static void virtio_blk_class_init(ObjectClass *klass, void *data)
1303{
1304 DeviceClass *dc = DEVICE_CLASS(klass);
1305 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
1306
1307 device_class_set_props(dc, virtio_blk_properties);
1308 dc->vmsd = &vmstate_virtio_blk;
1309 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1310 vdc->realize = virtio_blk_device_realize;
1311 vdc->unrealize = virtio_blk_device_unrealize;
1312 vdc->get_config = virtio_blk_update_config;
1313 vdc->set_config = virtio_blk_set_config;
1314 vdc->get_features = virtio_blk_get_features;
1315 vdc->set_status = virtio_blk_set_status;
1316 vdc->reset = virtio_blk_reset;
1317 vdc->save = virtio_blk_save_device;
1318 vdc->load = virtio_blk_load_device;
1319 vdc->start_ioeventfd = virtio_blk_data_plane_start;
1320 vdc->stop_ioeventfd = virtio_blk_data_plane_stop;
1321}
1322
1323static const TypeInfo virtio_blk_info = {
1324 .name = TYPE_VIRTIO_BLK,
1325 .parent = TYPE_VIRTIO_DEVICE,
1326 .instance_size = sizeof(VirtIOBlock),
1327 .instance_init = virtio_blk_instance_init,
1328 .class_init = virtio_blk_class_init,
1329};
1330
1331static void virtio_register_types(void)
1332{
1333 type_register_static(&virtio_blk_info);
1334}
1335
1336type_init(virtio_register_types)
1337