1 /*
2 * Virtio Block Device
3 *
4 * Copyright IBM, Corp. 2007
5 *
6 * Authors:
7 * Anthony Liguori <aliguori@us.ibm.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2. See
10 * the COPYING file in the top-level directory.
11 *
12 */
13
14 #include "qemu/osdep.h"
15 #include "qemu/defer-call.h"
16 #include "qapi/error.h"
17 #include "qemu/iov.h"
18 #include "qemu/module.h"
19 #include "qemu/error-report.h"
20 #include "qemu/main-loop.h"
21 #include "block/block_int.h"
22 #include "trace.h"
23 #include "hw/block/block.h"
24 #include "hw/qdev-properties.h"
25 #include "system/blockdev.h"
26 #include "system/block-ram-registrar.h"
27 #include "system/system.h"
28 #include "system/runstate.h"
29 #include "hw/virtio/virtio-blk.h"
30 #include "scsi/constants.h"
31 #ifdef __linux__
32 # include <scsi/sg.h>
33 #endif
34 #include "hw/virtio/virtio-bus.h"
35 #include "migration/qemu-file-types.h"
36 #include "hw/virtio/iothread-vq-mapping.h"
37 #include "hw/virtio/virtio-access.h"
38 #include "hw/virtio/virtio-blk-common.h"
39 #include "qemu/coroutine.h"
40
41 static void virtio_blk_ioeventfd_attach(VirtIOBlock *s);
42
virtio_blk_init_request(VirtIOBlock * s,VirtQueue * vq,VirtIOBlockReq * req)43 static void virtio_blk_init_request(VirtIOBlock *s, VirtQueue *vq,
44 VirtIOBlockReq *req)
45 {
46 req->dev = s;
47 req->vq = vq;
48 req->qiov.size = 0;
49 req->in_len = 0;
50 req->next = NULL;
51 req->mr_next = NULL;
52 }
53
virtio_blk_req_complete(VirtIOBlockReq * req,unsigned char status)54 void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status)
55 {
56 VirtIOBlock *s = req->dev;
57 VirtIODevice *vdev = VIRTIO_DEVICE(s);
58
59 trace_virtio_blk_req_complete(vdev, req, status);
60
61 stb_p(&req->in->status, status);
62 iov_discard_undo(&req->inhdr_undo);
63 iov_discard_undo(&req->outhdr_undo);
64 virtqueue_push(req->vq, &req->elem, req->in_len);
65 if (qemu_in_iothread()) {
66 virtio_notify_irqfd(vdev, req->vq);
67 } else {
68 virtio_notify(vdev, req->vq);
69 }
70 }
71
virtio_blk_handle_rw_error(VirtIOBlockReq * req,int error,bool is_read,bool acct_failed)72 static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error,
73 bool is_read, bool acct_failed)
74 {
75 VirtIOBlock *s = req->dev;
76 BlockErrorAction action = blk_get_error_action(s->blk, is_read, error);
77
78 if (action == BLOCK_ERROR_ACTION_STOP) {
79 /* Break the link as the next request is going to be parsed from the
80 * ring again. Otherwise we may end up doing a double completion! */
81 req->mr_next = NULL;
82
83 WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
84 req->next = s->rq;
85 s->rq = req;
86 }
87 } else if (action == BLOCK_ERROR_ACTION_REPORT) {
88 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
89 if (acct_failed) {
90 block_acct_failed(blk_get_stats(s->blk), &req->acct);
91 }
92 g_free(req);
93 }
94
95 blk_error_action(s->blk, action, is_read, error);
96 return action != BLOCK_ERROR_ACTION_IGNORE;
97 }
98
virtio_blk_rw_complete(void * opaque,int ret)99 static void virtio_blk_rw_complete(void *opaque, int ret)
100 {
101 VirtIOBlockReq *next = opaque;
102 VirtIOBlock *s = next->dev;
103 VirtIODevice *vdev = VIRTIO_DEVICE(s);
104
105 while (next) {
106 VirtIOBlockReq *req = next;
107 next = req->mr_next;
108 trace_virtio_blk_rw_complete(vdev, req, ret);
109
110 if (req->qiov.nalloc != -1) {
111 /* If nalloc is != -1 req->qiov is a local copy of the original
112 * external iovec. It was allocated in submit_requests to be
113 * able to merge requests. */
114 qemu_iovec_destroy(&req->qiov);
115 }
116
117 if (ret) {
118 int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type);
119 bool is_read = !(p & VIRTIO_BLK_T_OUT);
120 /* Note that memory may be dirtied on read failure. If the
121 * virtio request is not completed here, as is the case for
122 * BLOCK_ERROR_ACTION_STOP, the memory may not be copied
123 * correctly during live migration. While this is ugly,
124 * it is acceptable because the device is free to write to
125 * the memory until the request is completed (which will
126 * happen on the other side of the migration).
127 */
128 if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) {
129 continue;
130 }
131 }
132
133 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
134 block_acct_done(blk_get_stats(s->blk), &req->acct);
135 g_free(req);
136 }
137 }
138
virtio_blk_flush_complete(void * opaque,int ret)139 static void virtio_blk_flush_complete(void *opaque, int ret)
140 {
141 VirtIOBlockReq *req = opaque;
142 VirtIOBlock *s = req->dev;
143
144 if (ret && virtio_blk_handle_rw_error(req, -ret, 0, true)) {
145 return;
146 }
147
148 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
149 block_acct_done(blk_get_stats(s->blk), &req->acct);
150 g_free(req);
151 }
152
virtio_blk_discard_write_zeroes_complete(void * opaque,int ret)153 static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret)
154 {
155 VirtIOBlockReq *req = opaque;
156 VirtIOBlock *s = req->dev;
157 bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) &
158 ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES;
159
160 if (ret && virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) {
161 return;
162 }
163
164 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
165 if (is_write_zeroes) {
166 block_acct_done(blk_get_stats(s->blk), &req->acct);
167 }
168 g_free(req);
169 }
170
virtio_blk_get_request(VirtIOBlock * s,VirtQueue * vq)171 static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq)
172 {
173 VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq));
174
175 if (req) {
176 virtio_blk_init_request(s, vq, req);
177 }
178 return req;
179 }
180
virtio_blk_handle_scsi(VirtIOBlockReq * req)181 static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
182 {
183 int status;
184 struct virtio_scsi_inhdr *scsi;
185 VirtIOBlock *blk = req->dev;
186 VirtIODevice *vdev = VIRTIO_DEVICE(blk);
187 VirtQueueElement *elem = &req->elem;
188
189 /*
190 * We require at least one output segment each for the virtio_blk_outhdr
191 * and the SCSI command block.
192 *
193 * We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr
194 * and the sense buffer pointer in the input segments.
195 */
196 if (elem->out_num < 2 || elem->in_num < 3) {
197 status = VIRTIO_BLK_S_IOERR;
198 goto fail;
199 }
200
201 /*
202 * The scsi inhdr is placed in the second-to-last input segment, just
203 * before the regular inhdr.
204 *
205 * Just put anything nonzero so that the ioctl fails in the guest.
206 */
207 scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base;
208 virtio_stl_p(vdev, &scsi->errors, 255);
209 status = VIRTIO_BLK_S_UNSUPP;
210
211 fail:
212 virtio_blk_req_complete(req, status);
213 g_free(req);
214 }
215
submit_requests(VirtIOBlock * s,MultiReqBuffer * mrb,int start,int num_reqs,int niov)216 static inline void submit_requests(VirtIOBlock *s, MultiReqBuffer *mrb,
217 int start, int num_reqs, int niov)
218 {
219 BlockBackend *blk = s->blk;
220 QEMUIOVector *qiov = &mrb->reqs[start]->qiov;
221 int64_t sector_num = mrb->reqs[start]->sector_num;
222 bool is_write = mrb->is_write;
223 BdrvRequestFlags flags = 0;
224
225 if (num_reqs > 1) {
226 int i;
227 struct iovec *tmp_iov = qiov->iov;
228 int tmp_niov = qiov->niov;
229
230 /* mrb->reqs[start]->qiov was initialized from external so we can't
231 * modify it here. We need to initialize it locally and then add the
232 * external iovecs. */
233 qemu_iovec_init(qiov, niov);
234
235 for (i = 0; i < tmp_niov; i++) {
236 qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len);
237 }
238
239 for (i = start + 1; i < start + num_reqs; i++) {
240 qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0,
241 mrb->reqs[i]->qiov.size);
242 mrb->reqs[i - 1]->mr_next = mrb->reqs[i];
243 }
244
245 trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev),
246 mrb, start, num_reqs,
247 sector_num << BDRV_SECTOR_BITS,
248 qiov->size, is_write);
249 block_acct_merge_done(blk_get_stats(blk),
250 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ,
251 num_reqs - 1);
252 }
253
254 if (blk_ram_registrar_ok(&s->blk_ram_registrar)) {
255 flags |= BDRV_REQ_REGISTERED_BUF;
256 }
257
258 if (is_write) {
259 blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov,
260 flags, virtio_blk_rw_complete,
261 mrb->reqs[start]);
262 } else {
263 blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov,
264 flags, virtio_blk_rw_complete,
265 mrb->reqs[start]);
266 }
267 }
268
multireq_compare(const void * a,const void * b)269 static int multireq_compare(const void *a, const void *b)
270 {
271 const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a,
272 *req2 = *(VirtIOBlockReq **)b;
273
274 /*
275 * Note that we can't simply subtract sector_num1 from sector_num2
276 * here as that could overflow the return value.
277 */
278 if (req1->sector_num > req2->sector_num) {
279 return 1;
280 } else if (req1->sector_num < req2->sector_num) {
281 return -1;
282 } else {
283 return 0;
284 }
285 }
286
virtio_blk_submit_multireq(VirtIOBlock * s,MultiReqBuffer * mrb)287 static void virtio_blk_submit_multireq(VirtIOBlock *s, MultiReqBuffer *mrb)
288 {
289 int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0;
290 uint32_t max_transfer;
291 int64_t sector_num = 0;
292
293 if (mrb->num_reqs == 1) {
294 submit_requests(s, mrb, 0, 1, -1);
295 mrb->num_reqs = 0;
296 return;
297 }
298
299 max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk);
300
301 qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),
302 &multireq_compare);
303
304 for (i = 0; i < mrb->num_reqs; i++) {
305 VirtIOBlockReq *req = mrb->reqs[i];
306 if (num_reqs > 0) {
307 /*
308 * NOTE: We cannot merge the requests in below situations:
309 * 1. requests are not sequential
310 * 2. merge would exceed maximum number of IOVs
311 * 3. merge would exceed maximum transfer length of backend device
312 */
313 if (sector_num + nb_sectors != req->sector_num ||
314 niov > blk_get_max_iov(s->blk) - req->qiov.niov ||
315 req->qiov.size > max_transfer ||
316 nb_sectors > (max_transfer -
317 req->qiov.size) / BDRV_SECTOR_SIZE) {
318 submit_requests(s, mrb, start, num_reqs, niov);
319 num_reqs = 0;
320 }
321 }
322
323 if (num_reqs == 0) {
324 sector_num = req->sector_num;
325 nb_sectors = niov = 0;
326 start = i;
327 }
328
329 nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE;
330 niov += req->qiov.niov;
331 num_reqs++;
332 }
333
334 submit_requests(s, mrb, start, num_reqs, niov);
335 mrb->num_reqs = 0;
336 }
337
virtio_blk_handle_flush(VirtIOBlockReq * req,MultiReqBuffer * mrb)338 static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
339 {
340 VirtIOBlock *s = req->dev;
341
342 block_acct_start(blk_get_stats(s->blk), &req->acct, 0,
343 BLOCK_ACCT_FLUSH);
344
345 /*
346 * Make sure all outstanding writes are posted to the backing device.
347 */
348 if (mrb->is_write && mrb->num_reqs > 0) {
349 virtio_blk_submit_multireq(s, mrb);
350 }
351 blk_aio_flush(s->blk, virtio_blk_flush_complete, req);
352 }
353
virtio_blk_sect_range_ok(VirtIOBlock * dev,uint64_t sector,size_t size)354 static bool virtio_blk_sect_range_ok(VirtIOBlock *dev,
355 uint64_t sector, size_t size)
356 {
357 uint64_t nb_sectors = size >> BDRV_SECTOR_BITS;
358 uint64_t total_sectors;
359
360 if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
361 return false;
362 }
363 if (sector & dev->sector_mask) {
364 return false;
365 }
366 if (size % dev->conf.conf.logical_block_size) {
367 return false;
368 }
369 blk_get_geometry(dev->blk, &total_sectors);
370 if (sector > total_sectors || nb_sectors > total_sectors - sector) {
371 return false;
372 }
373 return true;
374 }
375
virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq * req,struct virtio_blk_discard_write_zeroes * dwz_hdr,bool is_write_zeroes)376 static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req,
377 struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes)
378 {
379 VirtIOBlock *s = req->dev;
380 VirtIODevice *vdev = VIRTIO_DEVICE(s);
381 uint64_t sector;
382 uint32_t num_sectors, flags, max_sectors;
383 uint8_t err_status;
384 int bytes;
385
386 sector = virtio_ldq_p(vdev, &dwz_hdr->sector);
387 num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors);
388 flags = virtio_ldl_p(vdev, &dwz_hdr->flags);
389 max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors :
390 s->conf.max_discard_sectors;
391
392 /*
393 * max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check
394 * make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in
395 * the integer variable.
396 */
397 if (unlikely(num_sectors > max_sectors)) {
398 err_status = VIRTIO_BLK_S_IOERR;
399 goto err;
400 }
401
402 bytes = num_sectors << BDRV_SECTOR_BITS;
403
404 if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) {
405 err_status = VIRTIO_BLK_S_IOERR;
406 goto err;
407 }
408
409 /*
410 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard
411 * and write zeroes commands if any unknown flag is set.
412 */
413 if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
414 err_status = VIRTIO_BLK_S_UNSUPP;
415 goto err;
416 }
417
418 if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */
419 int blk_aio_flags = 0;
420
421 if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
422 blk_aio_flags |= BDRV_REQ_MAY_UNMAP;
423 }
424
425 block_acct_start(blk_get_stats(s->blk), &req->acct, bytes,
426 BLOCK_ACCT_WRITE);
427
428 blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS,
429 bytes, blk_aio_flags,
430 virtio_blk_discard_write_zeroes_complete, req);
431 } else { /* VIRTIO_BLK_T_DISCARD */
432 /*
433 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for
434 * discard commands if the unmap flag is set.
435 */
436 if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
437 err_status = VIRTIO_BLK_S_UNSUPP;
438 goto err;
439 }
440
441 blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes,
442 virtio_blk_discard_write_zeroes_complete, req);
443 }
444
445 return VIRTIO_BLK_S_OK;
446
447 err:
448 if (is_write_zeroes) {
449 block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE);
450 }
451 return err_status;
452 }
453
454 typedef struct ZoneCmdData {
455 VirtIOBlockReq *req;
456 struct iovec *in_iov;
457 unsigned in_num;
458 union {
459 struct {
460 unsigned int nr_zones;
461 BlockZoneDescriptor *zones;
462 } zone_report_data;
463 struct {
464 int64_t offset;
465 } zone_append_data;
466 };
467 } ZoneCmdData;
468
469 /*
470 * check zoned_request: error checking before issuing requests. If all checks
471 * passed, return true.
472 * append: true if only zone append requests issued.
473 */
check_zoned_request(VirtIOBlock * s,int64_t offset,int64_t len,bool append,uint8_t * status)474 static bool check_zoned_request(VirtIOBlock *s, int64_t offset, int64_t len,
475 bool append, uint8_t *status) {
476 BlockDriverState *bs = blk_bs(s->blk);
477 int index;
478
479 if (!virtio_has_feature(s->host_features, VIRTIO_BLK_F_ZONED)) {
480 *status = VIRTIO_BLK_S_UNSUPP;
481 return false;
482 }
483
484 if (offset < 0 || len < 0 || len > (bs->total_sectors << BDRV_SECTOR_BITS)
485 || offset > (bs->total_sectors << BDRV_SECTOR_BITS) - len) {
486 *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
487 return false;
488 }
489
490 if (append) {
491 if (bs->bl.write_granularity) {
492 if ((offset % bs->bl.write_granularity) != 0) {
493 *status = VIRTIO_BLK_S_ZONE_UNALIGNED_WP;
494 return false;
495 }
496 }
497
498 index = offset / bs->bl.zone_size;
499 if (BDRV_ZT_IS_CONV(bs->wps->wp[index])) {
500 *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
501 return false;
502 }
503
504 if (len / 512 > bs->bl.max_append_sectors) {
505 if (bs->bl.max_append_sectors == 0) {
506 *status = VIRTIO_BLK_S_UNSUPP;
507 } else {
508 *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
509 }
510 return false;
511 }
512 }
513 return true;
514 }
515
virtio_blk_zone_report_complete(void * opaque,int ret)516 static void virtio_blk_zone_report_complete(void *opaque, int ret)
517 {
518 ZoneCmdData *data = opaque;
519 VirtIOBlockReq *req = data->req;
520 VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
521 struct iovec *in_iov = data->in_iov;
522 unsigned in_num = data->in_num;
523 int64_t zrp_size, n, j = 0;
524 int64_t nz = data->zone_report_data.nr_zones;
525 int8_t err_status = VIRTIO_BLK_S_OK;
526 struct virtio_blk_zone_report zrp_hdr = (struct virtio_blk_zone_report) {
527 .nr_zones = cpu_to_le64(nz),
528 };
529
530 trace_virtio_blk_zone_report_complete(vdev, req, nz, ret);
531 if (ret) {
532 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
533 goto out;
534 }
535
536 zrp_size = sizeof(struct virtio_blk_zone_report)
537 + sizeof(struct virtio_blk_zone_descriptor) * nz;
538 n = iov_from_buf(in_iov, in_num, 0, &zrp_hdr, sizeof(zrp_hdr));
539 if (n != sizeof(zrp_hdr)) {
540 virtio_error(vdev, "Driver provided input buffer that is too small!");
541 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
542 goto out;
543 }
544
545 for (size_t i = sizeof(zrp_hdr); i < zrp_size;
546 i += sizeof(struct virtio_blk_zone_descriptor), ++j) {
547 struct virtio_blk_zone_descriptor desc =
548 (struct virtio_blk_zone_descriptor) {
549 .z_start = cpu_to_le64(data->zone_report_data.zones[j].start
550 >> BDRV_SECTOR_BITS),
551 .z_cap = cpu_to_le64(data->zone_report_data.zones[j].cap
552 >> BDRV_SECTOR_BITS),
553 .z_wp = cpu_to_le64(data->zone_report_data.zones[j].wp
554 >> BDRV_SECTOR_BITS),
555 };
556
557 switch (data->zone_report_data.zones[j].type) {
558 case BLK_ZT_CONV:
559 desc.z_type = VIRTIO_BLK_ZT_CONV;
560 break;
561 case BLK_ZT_SWR:
562 desc.z_type = VIRTIO_BLK_ZT_SWR;
563 break;
564 case BLK_ZT_SWP:
565 desc.z_type = VIRTIO_BLK_ZT_SWP;
566 break;
567 default:
568 g_assert_not_reached();
569 }
570
571 switch (data->zone_report_data.zones[j].state) {
572 case BLK_ZS_RDONLY:
573 desc.z_state = VIRTIO_BLK_ZS_RDONLY;
574 break;
575 case BLK_ZS_OFFLINE:
576 desc.z_state = VIRTIO_BLK_ZS_OFFLINE;
577 break;
578 case BLK_ZS_EMPTY:
579 desc.z_state = VIRTIO_BLK_ZS_EMPTY;
580 break;
581 case BLK_ZS_CLOSED:
582 desc.z_state = VIRTIO_BLK_ZS_CLOSED;
583 break;
584 case BLK_ZS_FULL:
585 desc.z_state = VIRTIO_BLK_ZS_FULL;
586 break;
587 case BLK_ZS_EOPEN:
588 desc.z_state = VIRTIO_BLK_ZS_EOPEN;
589 break;
590 case BLK_ZS_IOPEN:
591 desc.z_state = VIRTIO_BLK_ZS_IOPEN;
592 break;
593 case BLK_ZS_NOT_WP:
594 desc.z_state = VIRTIO_BLK_ZS_NOT_WP;
595 break;
596 default:
597 g_assert_not_reached();
598 }
599
600 /* TODO: it takes O(n^2) time complexity. Optimizations required. */
601 n = iov_from_buf(in_iov, in_num, i, &desc, sizeof(desc));
602 if (n != sizeof(desc)) {
603 virtio_error(vdev, "Driver provided input buffer "
604 "for descriptors that is too small!");
605 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
606 }
607 }
608
609 out:
610 virtio_blk_req_complete(req, err_status);
611 g_free(req);
612 g_free(data->zone_report_data.zones);
613 g_free(data);
614 }
615
virtio_blk_handle_zone_report(VirtIOBlockReq * req,struct iovec * in_iov,unsigned in_num)616 static void virtio_blk_handle_zone_report(VirtIOBlockReq *req,
617 struct iovec *in_iov,
618 unsigned in_num)
619 {
620 VirtIOBlock *s = req->dev;
621 VirtIODevice *vdev = VIRTIO_DEVICE(s);
622 unsigned int nr_zones;
623 ZoneCmdData *data;
624 int64_t zone_size, offset;
625 uint8_t err_status;
626
627 if (req->in_len < sizeof(struct virtio_blk_inhdr) +
628 sizeof(struct virtio_blk_zone_report) +
629 sizeof(struct virtio_blk_zone_descriptor)) {
630 virtio_error(vdev, "in buffer too small for zone report");
631 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
632 goto out;
633 }
634
635 /* start byte offset of the zone report */
636 offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
637 if (!check_zoned_request(s, offset, 0, false, &err_status)) {
638 goto out;
639 }
640 nr_zones = (req->in_len - sizeof(struct virtio_blk_inhdr) -
641 sizeof(struct virtio_blk_zone_report)) /
642 sizeof(struct virtio_blk_zone_descriptor);
643 trace_virtio_blk_handle_zone_report(vdev, req,
644 offset >> BDRV_SECTOR_BITS, nr_zones);
645
646 zone_size = sizeof(BlockZoneDescriptor) * nr_zones;
647 data = g_malloc(sizeof(ZoneCmdData));
648 data->req = req;
649 data->in_iov = in_iov;
650 data->in_num = in_num;
651 data->zone_report_data.nr_zones = nr_zones;
652 data->zone_report_data.zones = g_malloc(zone_size),
653
654 blk_aio_zone_report(s->blk, offset, &data->zone_report_data.nr_zones,
655 data->zone_report_data.zones,
656 virtio_blk_zone_report_complete, data);
657 return;
658 out:
659 virtio_blk_req_complete(req, err_status);
660 g_free(req);
661 }
662
virtio_blk_zone_mgmt_complete(void * opaque,int ret)663 static void virtio_blk_zone_mgmt_complete(void *opaque, int ret)
664 {
665 VirtIOBlockReq *req = opaque;
666 VirtIOBlock *s = req->dev;
667 VirtIODevice *vdev = VIRTIO_DEVICE(s);
668 int8_t err_status = VIRTIO_BLK_S_OK;
669 trace_virtio_blk_zone_mgmt_complete(vdev, req,ret);
670
671 if (ret) {
672 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
673 }
674
675 virtio_blk_req_complete(req, err_status);
676 g_free(req);
677 }
678
virtio_blk_handle_zone_mgmt(VirtIOBlockReq * req,BlockZoneOp op)679 static int virtio_blk_handle_zone_mgmt(VirtIOBlockReq *req, BlockZoneOp op)
680 {
681 VirtIOBlock *s = req->dev;
682 VirtIODevice *vdev = VIRTIO_DEVICE(s);
683 BlockDriverState *bs = blk_bs(s->blk);
684 int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
685 uint64_t len;
686 uint64_t capacity = bs->total_sectors << BDRV_SECTOR_BITS;
687 uint8_t err_status = VIRTIO_BLK_S_OK;
688
689 uint32_t type = virtio_ldl_p(vdev, &req->out.type);
690 if (type == VIRTIO_BLK_T_ZONE_RESET_ALL) {
691 /* Entire drive capacity */
692 offset = 0;
693 len = capacity;
694 trace_virtio_blk_handle_zone_reset_all(vdev, req, 0,
695 bs->total_sectors);
696 } else {
697 if (bs->bl.zone_size > capacity - offset) {
698 /* The zoned device allows the last smaller zone. */
699 len = capacity - bs->bl.zone_size * (bs->bl.nr_zones - 1ull);
700 } else {
701 len = bs->bl.zone_size;
702 }
703 trace_virtio_blk_handle_zone_mgmt(vdev, req, op,
704 offset >> BDRV_SECTOR_BITS,
705 len >> BDRV_SECTOR_BITS);
706 }
707
708 if (!check_zoned_request(s, offset, len, false, &err_status)) {
709 goto out;
710 }
711
712 blk_aio_zone_mgmt(s->blk, op, offset, len,
713 virtio_blk_zone_mgmt_complete, req);
714
715 return 0;
716 out:
717 virtio_blk_req_complete(req, err_status);
718 g_free(req);
719 return err_status;
720 }
721
virtio_blk_zone_append_complete(void * opaque,int ret)722 static void virtio_blk_zone_append_complete(void *opaque, int ret)
723 {
724 ZoneCmdData *data = opaque;
725 VirtIOBlockReq *req = data->req;
726 VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
727 int64_t append_sector, n;
728 uint8_t err_status = VIRTIO_BLK_S_OK;
729
730 if (ret) {
731 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
732 goto out;
733 }
734
735 virtio_stq_p(vdev, &append_sector,
736 data->zone_append_data.offset >> BDRV_SECTOR_BITS);
737 n = iov_from_buf(data->in_iov, data->in_num, 0, &append_sector,
738 sizeof(append_sector));
739 if (n != sizeof(append_sector)) {
740 virtio_error(vdev, "Driver provided input buffer less than size of "
741 "append_sector");
742 err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
743 goto out;
744 }
745 trace_virtio_blk_zone_append_complete(vdev, req, append_sector, ret);
746
747 out:
748 virtio_blk_req_complete(req, err_status);
749 g_free(req);
750 g_free(data);
751 }
752
virtio_blk_handle_zone_append(VirtIOBlockReq * req,struct iovec * out_iov,struct iovec * in_iov,uint64_t out_num,unsigned in_num)753 static int virtio_blk_handle_zone_append(VirtIOBlockReq *req,
754 struct iovec *out_iov,
755 struct iovec *in_iov,
756 uint64_t out_num,
757 unsigned in_num) {
758 VirtIOBlock *s = req->dev;
759 VirtIODevice *vdev = VIRTIO_DEVICE(s);
760 uint8_t err_status = VIRTIO_BLK_S_OK;
761
762 int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
763 int64_t len = iov_size(out_iov, out_num);
764 ZoneCmdData *data;
765
766 trace_virtio_blk_handle_zone_append(vdev, req, offset >> BDRV_SECTOR_BITS);
767 if (!check_zoned_request(s, offset, len, true, &err_status)) {
768 goto out;
769 }
770
771 data = g_malloc(sizeof(ZoneCmdData));
772 data->req = req;
773 data->in_iov = in_iov;
774 data->in_num = in_num;
775 data->zone_append_data.offset = offset;
776 qemu_iovec_init_external(&req->qiov, out_iov, out_num);
777
778 block_acct_start(blk_get_stats(s->blk), &req->acct, len,
779 BLOCK_ACCT_ZONE_APPEND);
780
781 blk_aio_zone_append(s->blk, &data->zone_append_data.offset, &req->qiov, 0,
782 virtio_blk_zone_append_complete, data);
783 return 0;
784
785 out:
786 virtio_blk_req_complete(req, err_status);
787 g_free(req);
788 return err_status;
789 }
790
virtio_blk_handle_request(VirtIOBlockReq * req,MultiReqBuffer * mrb)791 static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
792 {
793 uint32_t type;
794 struct iovec *in_iov = req->elem.in_sg;
795 struct iovec *out_iov = req->elem.out_sg;
796 unsigned in_num = req->elem.in_num;
797 unsigned out_num = req->elem.out_num;
798 VirtIOBlock *s = req->dev;
799 VirtIODevice *vdev = VIRTIO_DEVICE(s);
800
801 if (req->elem.out_num < 1 || req->elem.in_num < 1) {
802 virtio_error(vdev, "virtio-blk missing headers");
803 return -1;
804 }
805
806 if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
807 sizeof(req->out)) != sizeof(req->out))) {
808 virtio_error(vdev, "virtio-blk request outhdr too short");
809 return -1;
810 }
811
812 iov_discard_front_undoable(&out_iov, &out_num, sizeof(req->out),
813 &req->outhdr_undo);
814
815 if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
816 virtio_error(vdev, "virtio-blk request inhdr too short");
817 iov_discard_undo(&req->outhdr_undo);
818 return -1;
819 }
820
821 /* We always touch the last byte, so just see how big in_iov is. */
822 req->in_len = iov_size(in_iov, in_num);
823 req->in = (void *)in_iov[in_num - 1].iov_base
824 + in_iov[in_num - 1].iov_len
825 - sizeof(struct virtio_blk_inhdr);
826 iov_discard_back_undoable(in_iov, &in_num, sizeof(struct virtio_blk_inhdr),
827 &req->inhdr_undo);
828
829 type = virtio_ldl_p(vdev, &req->out.type);
830
831 /* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER
832 * is an optional flag. Although a guest should not send this flag if
833 * not negotiated we ignored it in the past. So keep ignoring it. */
834 switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) {
835 case VIRTIO_BLK_T_IN:
836 {
837 bool is_write = type & VIRTIO_BLK_T_OUT;
838 req->sector_num = virtio_ldq_p(vdev, &req->out.sector);
839
840 if (is_write) {
841 qemu_iovec_init_external(&req->qiov, out_iov, out_num);
842 trace_virtio_blk_handle_write(vdev, req, req->sector_num,
843 req->qiov.size / BDRV_SECTOR_SIZE);
844 } else {
845 qemu_iovec_init_external(&req->qiov, in_iov, in_num);
846 trace_virtio_blk_handle_read(vdev, req, req->sector_num,
847 req->qiov.size / BDRV_SECTOR_SIZE);
848 }
849
850 if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) {
851 virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
852 block_acct_invalid(blk_get_stats(s->blk),
853 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
854 g_free(req);
855 return 0;
856 }
857
858 block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size,
859 is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
860
861 /* merge would exceed maximum number of requests or IO direction
862 * changes */
863 if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS ||
864 is_write != mrb->is_write ||
865 !s->conf.request_merging)) {
866 virtio_blk_submit_multireq(s, mrb);
867 }
868
869 assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS);
870 mrb->reqs[mrb->num_reqs++] = req;
871 mrb->is_write = is_write;
872 break;
873 }
874 case VIRTIO_BLK_T_FLUSH:
875 virtio_blk_handle_flush(req, mrb);
876 break;
877 case VIRTIO_BLK_T_ZONE_REPORT:
878 virtio_blk_handle_zone_report(req, in_iov, in_num);
879 break;
880 case VIRTIO_BLK_T_ZONE_OPEN:
881 virtio_blk_handle_zone_mgmt(req, BLK_ZO_OPEN);
882 break;
883 case VIRTIO_BLK_T_ZONE_CLOSE:
884 virtio_blk_handle_zone_mgmt(req, BLK_ZO_CLOSE);
885 break;
886 case VIRTIO_BLK_T_ZONE_FINISH:
887 virtio_blk_handle_zone_mgmt(req, BLK_ZO_FINISH);
888 break;
889 case VIRTIO_BLK_T_ZONE_RESET:
890 virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
891 break;
892 case VIRTIO_BLK_T_ZONE_RESET_ALL:
893 virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
894 break;
895 case VIRTIO_BLK_T_SCSI_CMD:
896 virtio_blk_handle_scsi(req);
897 break;
898 case VIRTIO_BLK_T_GET_ID:
899 {
900 /*
901 * NB: per existing s/n string convention the string is
902 * terminated by '\0' only when shorter than buffer.
903 */
904 const char *serial = s->conf.serial ? s->conf.serial : "";
905 size_t size = MIN(strlen(serial) + 1,
906 MIN(iov_size(in_iov, in_num),
907 VIRTIO_BLK_ID_BYTES));
908 iov_from_buf(in_iov, in_num, 0, serial, size);
909 virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
910 g_free(req);
911 break;
912 }
913 case VIRTIO_BLK_T_ZONE_APPEND & ~VIRTIO_BLK_T_OUT:
914 /*
915 * Passing out_iov/out_num and in_iov/in_num is not safe
916 * to access req->elem.out_sg directly because it may be
917 * modified by virtio_blk_handle_request().
918 */
919 virtio_blk_handle_zone_append(req, out_iov, in_iov, out_num, in_num);
920 break;
921 /*
922 * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with
923 * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement,
924 * so we must mask it for these requests, then we will check if it is set.
925 */
926 case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT:
927 case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT:
928 {
929 struct virtio_blk_discard_write_zeroes dwz_hdr;
930 size_t out_len = iov_size(out_iov, out_num);
931 bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) ==
932 VIRTIO_BLK_T_WRITE_ZEROES;
933 uint8_t err_status;
934
935 /*
936 * Unsupported if VIRTIO_BLK_T_OUT is not set or the request contains
937 * more than one segment.
938 */
939 if (unlikely(!(type & VIRTIO_BLK_T_OUT) ||
940 out_len > sizeof(dwz_hdr))) {
941 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
942 g_free(req);
943 return 0;
944 }
945
946 if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr,
947 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) {
948 iov_discard_undo(&req->inhdr_undo);
949 iov_discard_undo(&req->outhdr_undo);
950 virtio_error(vdev, "virtio-blk discard/write_zeroes header"
951 " too short");
952 return -1;
953 }
954
955 err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr,
956 is_write_zeroes);
957 if (err_status != VIRTIO_BLK_S_OK) {
958 virtio_blk_req_complete(req, err_status);
959 g_free(req);
960 }
961
962 break;
963 }
964 default:
965 {
966 /*
967 * Give subclasses a chance to handle unknown requests. This way the
968 * class lookup is not in the hot path.
969 */
970 VirtIOBlkClass *vbk = VIRTIO_BLK_GET_CLASS(s);
971 if (!vbk->handle_unknown_request ||
972 !vbk->handle_unknown_request(req, mrb, type)) {
973 virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
974 g_free(req);
975 }
976 }
977 }
978 return 0;
979 }
980
virtio_blk_handle_vq(VirtIOBlock * s,VirtQueue * vq)981 void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq)
982 {
983 VirtIOBlockReq *req;
984 MultiReqBuffer mrb = {};
985 bool suppress_notifications = virtio_queue_get_notification(vq);
986
987 defer_call_begin();
988
989 do {
990 if (suppress_notifications) {
991 virtio_queue_set_notification(vq, 0);
992 }
993
994 while ((req = virtio_blk_get_request(s, vq))) {
995 if (virtio_blk_handle_request(req, &mrb)) {
996 virtqueue_detach_element(req->vq, &req->elem, 0);
997 g_free(req);
998 break;
999 }
1000 }
1001
1002 if (suppress_notifications) {
1003 virtio_queue_set_notification(vq, 1);
1004 }
1005 } while (!virtio_queue_empty(vq));
1006
1007 if (mrb.num_reqs) {
1008 virtio_blk_submit_multireq(s, &mrb);
1009 }
1010
1011 defer_call_end();
1012 }
1013
virtio_blk_handle_output(VirtIODevice * vdev,VirtQueue * vq)1014 static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
1015 {
1016 VirtIOBlock *s = (VirtIOBlock *)vdev;
1017
1018 if (!s->ioeventfd_disabled && !s->ioeventfd_started) {
1019 /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
1020 * ioeventfd here instead of waiting for .set_status().
1021 */
1022 virtio_device_start_ioeventfd(vdev);
1023 if (!s->ioeventfd_disabled) {
1024 return;
1025 }
1026 }
1027
1028 virtio_blk_handle_vq(s, vq);
1029 }
1030
virtio_blk_dma_restart_bh(void * opaque)1031 static void virtio_blk_dma_restart_bh(void *opaque)
1032 {
1033 VirtIOBlockReq *req = opaque;
1034 VirtIOBlock *s = req->dev; /* we're called with at least one request */
1035
1036 MultiReqBuffer mrb = {};
1037
1038 while (req) {
1039 VirtIOBlockReq *next = req->next;
1040 if (virtio_blk_handle_request(req, &mrb)) {
1041 /* Device is now broken and won't do any processing until it gets
1042 * reset. Already queued requests will be lost: let's purge them.
1043 */
1044 while (req) {
1045 next = req->next;
1046 virtqueue_detach_element(req->vq, &req->elem, 0);
1047 g_free(req);
1048 req = next;
1049 }
1050 break;
1051 }
1052 req = next;
1053 }
1054
1055 if (mrb.num_reqs) {
1056 virtio_blk_submit_multireq(s, &mrb);
1057 }
1058
1059 /* Paired with inc in virtio_blk_dma_restart_cb() */
1060 blk_dec_in_flight(s->conf.conf.blk);
1061 }
1062
virtio_blk_dma_restart_cb(void * opaque,bool running,RunState state)1063 static void virtio_blk_dma_restart_cb(void *opaque, bool running,
1064 RunState state)
1065 {
1066 VirtIOBlock *s = opaque;
1067 uint16_t num_queues = s->conf.num_queues;
1068 g_autofree VirtIOBlockReq **vq_rq = NULL;
1069 VirtIOBlockReq *rq = NULL;
1070
1071 if (!running) {
1072 return;
1073 }
1074
1075 /* Split the device-wide s->rq request list into per-vq request lists */
1076 vq_rq = g_new0(VirtIOBlockReq *, num_queues);
1077
1078 WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1079 rq = s->rq;
1080 s->rq = NULL;
1081 }
1082
1083 while (rq) {
1084 VirtIOBlockReq *next = rq->next;
1085 uint16_t idx = virtio_get_queue_index(rq->vq);
1086
1087 /* Only num_queues vqs were created so vq_rq[idx] is within bounds */
1088 assert(idx < num_queues);
1089 rq->next = vq_rq[idx];
1090 vq_rq[idx] = rq;
1091 rq = next;
1092 }
1093
1094 /* Schedule a BH to submit the requests in each vq's AioContext */
1095 for (uint16_t i = 0; i < num_queues; i++) {
1096 if (!vq_rq[i]) {
1097 continue;
1098 }
1099
1100 /* Paired with dec in virtio_blk_dma_restart_bh() */
1101 blk_inc_in_flight(s->conf.conf.blk);
1102
1103 aio_bh_schedule_oneshot(s->vq_aio_context[i],
1104 virtio_blk_dma_restart_bh,
1105 vq_rq[i]);
1106 }
1107 }
1108
virtio_blk_reset(VirtIODevice * vdev)1109 static void virtio_blk_reset(VirtIODevice *vdev)
1110 {
1111 VirtIOBlock *s = VIRTIO_BLK(vdev);
1112 VirtIOBlockReq *req;
1113
1114 /* Dataplane has stopped... */
1115 assert(!s->ioeventfd_started);
1116
1117 /* ...but requests may still be in flight. */
1118 blk_drain(s->blk);
1119
1120 /* We drop queued requests after blk_drain() because blk_drain() itself can
1121 * produce them. */
1122 WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1123 while (s->rq) {
1124 req = s->rq;
1125 s->rq = req->next;
1126
1127 /* No other threads can access req->vq here */
1128 virtqueue_detach_element(req->vq, &req->elem, 0);
1129
1130 g_free(req);
1131 }
1132 }
1133
1134 blk_set_enable_write_cache(s->blk, s->original_wce);
1135 }
1136
1137 /* coalesce internal state, copy to pci i/o region 0
1138 */
virtio_blk_update_config(VirtIODevice * vdev,uint8_t * config)1139 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
1140 {
1141 VirtIOBlock *s = VIRTIO_BLK(vdev);
1142 BlockConf *conf = &s->conf.conf;
1143 BlockDriverState *bs = blk_bs(s->blk);
1144 struct virtio_blk_config blkcfg;
1145 uint64_t capacity;
1146 int64_t length;
1147 int blk_size = conf->logical_block_size;
1148
1149 blk_get_geometry(s->blk, &capacity);
1150 memset(&blkcfg, 0, sizeof(blkcfg));
1151 virtio_stq_p(vdev, &blkcfg.capacity, capacity);
1152 virtio_stl_p(vdev, &blkcfg.seg_max,
1153 s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2);
1154 virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls);
1155 virtio_stl_p(vdev, &blkcfg.blk_size, blk_size);
1156 virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size);
1157 virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
1158 blkcfg.geometry.heads = conf->heads;
1159 /*
1160 * We must ensure that the block device capacity is a multiple of
1161 * the logical block size. If that is not the case, let's use
1162 * sector_mask to adopt the geometry to have a correct picture.
1163 * For those devices where the capacity is ok for the given geometry
1164 * we don't touch the sector value of the geometry, since some devices
1165 * (like s390 dasd) need a specific value. Here the capacity is already
1166 * cyls*heads*secs*blk_size and the sector value is not block size
1167 * divided by 512 - instead it is the amount of blk_size blocks
1168 * per track (cylinder).
1169 */
1170 length = blk_getlength(s->blk);
1171 if (length > 0 && length / conf->heads / conf->secs % blk_size) {
1172 blkcfg.geometry.sectors = conf->secs & ~s->sector_mask;
1173 } else {
1174 blkcfg.geometry.sectors = conf->secs;
1175 }
1176 blkcfg.size_max = 0;
1177 blkcfg.physical_block_exp = get_physical_block_exp(conf);
1178 blkcfg.alignment_offset = 0;
1179 blkcfg.wce = blk_enable_write_cache(s->blk);
1180 virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues);
1181 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) {
1182 uint32_t discard_granularity = conf->discard_granularity;
1183 if (discard_granularity == -1 || !s->conf.report_discard_granularity) {
1184 discard_granularity = blk_size;
1185 }
1186 virtio_stl_p(vdev, &blkcfg.max_discard_sectors,
1187 s->conf.max_discard_sectors);
1188 virtio_stl_p(vdev, &blkcfg.discard_sector_alignment,
1189 discard_granularity >> BDRV_SECTOR_BITS);
1190 /*
1191 * We support only one segment per request since multiple segments
1192 * are not widely used and there are no userspace APIs that allow
1193 * applications to submit multiple segments in a single call.
1194 */
1195 virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1);
1196 }
1197 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) {
1198 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors,
1199 s->conf.max_write_zeroes_sectors);
1200 blkcfg.write_zeroes_may_unmap = 1;
1201 virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1);
1202 }
1203 if (bs->bl.zoned != BLK_Z_NONE) {
1204 switch (bs->bl.zoned) {
1205 case BLK_Z_HM:
1206 blkcfg.zoned.model = VIRTIO_BLK_Z_HM;
1207 break;
1208 case BLK_Z_HA:
1209 blkcfg.zoned.model = VIRTIO_BLK_Z_HA;
1210 break;
1211 default:
1212 g_assert_not_reached();
1213 }
1214
1215 virtio_stl_p(vdev, &blkcfg.zoned.zone_sectors,
1216 bs->bl.zone_size / 512);
1217 virtio_stl_p(vdev, &blkcfg.zoned.max_active_zones,
1218 bs->bl.max_active_zones);
1219 virtio_stl_p(vdev, &blkcfg.zoned.max_open_zones,
1220 bs->bl.max_open_zones);
1221 virtio_stl_p(vdev, &blkcfg.zoned.write_granularity, blk_size);
1222 virtio_stl_p(vdev, &blkcfg.zoned.max_append_sectors,
1223 bs->bl.max_append_sectors);
1224 } else {
1225 blkcfg.zoned.model = VIRTIO_BLK_Z_NONE;
1226 }
1227 memcpy(config, &blkcfg, s->config_size);
1228 }
1229
virtio_blk_set_config(VirtIODevice * vdev,const uint8_t * config)1230 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
1231 {
1232 VirtIOBlock *s = VIRTIO_BLK(vdev);
1233 struct virtio_blk_config blkcfg;
1234
1235 memcpy(&blkcfg, config, s->config_size);
1236
1237 blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
1238 }
1239
virtio_blk_get_features(VirtIODevice * vdev,uint64_t features,Error ** errp)1240 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features,
1241 Error **errp)
1242 {
1243 VirtIOBlock *s = VIRTIO_BLK(vdev);
1244
1245 /* Firstly sync all virtio-blk possible supported features */
1246 features |= s->host_features;
1247
1248 virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX);
1249 virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY);
1250 virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY);
1251 virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE);
1252 if (!virtio_has_feature(features, VIRTIO_F_VERSION_1)) {
1253 virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT);
1254 /* Added for historical reasons, removing it could break migration. */
1255 virtio_add_feature(&features, VIRTIO_BLK_F_SCSI);
1256 }
1257
1258 if (blk_enable_write_cache(s->blk) ||
1259 (s->conf.x_enable_wce_if_config_wce &&
1260 virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) {
1261 virtio_add_feature(&features, VIRTIO_BLK_F_WCE);
1262 }
1263 if (!blk_is_writable(s->blk)) {
1264 virtio_add_feature(&features, VIRTIO_BLK_F_RO);
1265 }
1266 if (s->conf.num_queues > 1) {
1267 virtio_add_feature(&features, VIRTIO_BLK_F_MQ);
1268 }
1269
1270 return features;
1271 }
1272
virtio_blk_set_status(VirtIODevice * vdev,uint8_t status)1273 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
1274 {
1275 VirtIOBlock *s = VIRTIO_BLK(vdev);
1276
1277 if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) {
1278 assert(!s->ioeventfd_started);
1279 }
1280
1281 if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
1282 return;
1283 }
1284
1285 /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send
1286 * cache flushes. Thus, the "auto writethrough" behavior is never
1287 * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature.
1288 * Leaving it enabled would break the following sequence:
1289 *
1290 * Guest started with "-drive cache=writethrough"
1291 * Guest sets status to 0
1292 * Guest sets DRIVER bit in status field
1293 * Guest reads host features (WCE=0, CONFIG_WCE=1)
1294 * Guest writes guest features (WCE=0, CONFIG_WCE=1)
1295 * Guest writes 1 to the WCE configuration field (writeback mode)
1296 * Guest sets DRIVER_OK bit in status field
1297 *
1298 * s->blk would erroneously be placed in writethrough mode.
1299 */
1300 if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) {
1301 blk_set_enable_write_cache(s->blk,
1302 virtio_vdev_has_feature(vdev,
1303 VIRTIO_BLK_F_WCE));
1304 }
1305 }
1306
virtio_blk_save_device(VirtIODevice * vdev,QEMUFile * f)1307 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f)
1308 {
1309 VirtIOBlock *s = VIRTIO_BLK(vdev);
1310
1311 WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1312 VirtIOBlockReq *req = s->rq;
1313
1314 while (req) {
1315 qemu_put_sbyte(f, 1);
1316
1317 if (s->conf.num_queues > 1) {
1318 qemu_put_be32(f, virtio_get_queue_index(req->vq));
1319 }
1320
1321 qemu_put_virtqueue_element(vdev, f, &req->elem);
1322 req = req->next;
1323 }
1324 }
1325
1326 qemu_put_sbyte(f, 0);
1327 }
1328
virtio_blk_load_device(VirtIODevice * vdev,QEMUFile * f,int version_id)1329 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
1330 int version_id)
1331 {
1332 VirtIOBlock *s = VIRTIO_BLK(vdev);
1333
1334 while (qemu_get_sbyte(f)) {
1335 unsigned nvqs = s->conf.num_queues;
1336 unsigned vq_idx = 0;
1337 VirtIOBlockReq *req;
1338
1339 if (nvqs > 1) {
1340 vq_idx = qemu_get_be32(f);
1341
1342 if (vq_idx >= nvqs) {
1343 error_report("Invalid virtqueue index in request list: %#x",
1344 vq_idx);
1345 return -EINVAL;
1346 }
1347 }
1348
1349 req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq));
1350 virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req);
1351
1352 WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1353 req->next = s->rq;
1354 s->rq = req;
1355 }
1356 }
1357
1358 return 0;
1359 }
1360
virtio_resize_cb(void * opaque)1361 static void virtio_resize_cb(void *opaque)
1362 {
1363 VirtIODevice *vdev = opaque;
1364
1365 assert(qemu_get_current_aio_context() == qemu_get_aio_context());
1366 virtio_notify_config(vdev);
1367 }
1368
virtio_blk_resize(void * opaque)1369 static void virtio_blk_resize(void *opaque)
1370 {
1371 VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
1372
1373 /*
1374 * virtio_notify_config() needs to acquire the BQL,
1375 * so it can't be called from an iothread. Instead, schedule
1376 * it to be run in the main context BH.
1377 */
1378 aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev);
1379 }
1380
virtio_blk_ioeventfd_detach(VirtIOBlock * s)1381 static void virtio_blk_ioeventfd_detach(VirtIOBlock *s)
1382 {
1383 VirtIODevice *vdev = VIRTIO_DEVICE(s);
1384
1385 for (uint16_t i = 0; i < s->conf.num_queues; i++) {
1386 VirtQueue *vq = virtio_get_queue(vdev, i);
1387 virtio_queue_aio_detach_host_notifier(vq, s->vq_aio_context[i]);
1388 }
1389 }
1390
virtio_blk_ioeventfd_attach(VirtIOBlock * s)1391 static void virtio_blk_ioeventfd_attach(VirtIOBlock *s)
1392 {
1393 VirtIODevice *vdev = VIRTIO_DEVICE(s);
1394
1395 for (uint16_t i = 0; i < s->conf.num_queues; i++) {
1396 VirtQueue *vq = virtio_get_queue(vdev, i);
1397 virtio_queue_aio_attach_host_notifier(vq, s->vq_aio_context[i]);
1398 }
1399 }
1400
1401 /* Suspend virtqueue ioeventfd processing during drain */
virtio_blk_drained_begin(void * opaque)1402 static void virtio_blk_drained_begin(void *opaque)
1403 {
1404 VirtIOBlock *s = opaque;
1405
1406 if (s->ioeventfd_started) {
1407 virtio_blk_ioeventfd_detach(s);
1408 }
1409 }
1410
1411 /* Resume virtqueue ioeventfd processing after drain */
virtio_blk_drained_end(void * opaque)1412 static void virtio_blk_drained_end(void *opaque)
1413 {
1414 VirtIOBlock *s = opaque;
1415
1416 if (s->ioeventfd_started) {
1417 virtio_blk_ioeventfd_attach(s);
1418 }
1419 }
1420
1421 static const BlockDevOps virtio_block_ops = {
1422 .resize_cb = virtio_blk_resize,
1423 .drained_begin = virtio_blk_drained_begin,
1424 .drained_end = virtio_blk_drained_end,
1425 };
1426
1427 /* Context: BQL held */
virtio_blk_vq_aio_context_init(VirtIOBlock * s,Error ** errp)1428 static bool virtio_blk_vq_aio_context_init(VirtIOBlock *s, Error **errp)
1429 {
1430 ERRP_GUARD();
1431 VirtIODevice *vdev = VIRTIO_DEVICE(s);
1432 VirtIOBlkConf *conf = &s->conf;
1433 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
1434 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
1435
1436 if (conf->iothread && conf->iothread_vq_mapping_list) {
1437 error_setg(errp,
1438 "iothread and iothread-vq-mapping properties cannot be set "
1439 "at the same time");
1440 return false;
1441 }
1442
1443 if (conf->iothread || conf->iothread_vq_mapping_list) {
1444 if (!k->set_guest_notifiers || !k->ioeventfd_assign) {
1445 error_setg(errp,
1446 "device is incompatible with iothread "
1447 "(transport does not support notifiers)");
1448 return false;
1449 }
1450 if (!virtio_device_ioeventfd_enabled(vdev)) {
1451 error_setg(errp, "ioeventfd is required for iothread");
1452 return false;
1453 }
1454 }
1455
1456 s->vq_aio_context = g_new(AioContext *, conf->num_queues);
1457
1458 if (conf->iothread_vq_mapping_list) {
1459 if (!iothread_vq_mapping_apply(conf->iothread_vq_mapping_list,
1460 s->vq_aio_context,
1461 conf->num_queues,
1462 errp)) {
1463 g_free(s->vq_aio_context);
1464 s->vq_aio_context = NULL;
1465 return false;
1466 }
1467 } else if (conf->iothread) {
1468 AioContext *ctx = iothread_get_aio_context(conf->iothread);
1469 for (unsigned i = 0; i < conf->num_queues; i++) {
1470 s->vq_aio_context[i] = ctx;
1471 }
1472
1473 /* Released in virtio_blk_vq_aio_context_cleanup() */
1474 object_ref(OBJECT(conf->iothread));
1475 } else {
1476 AioContext *ctx = qemu_get_aio_context();
1477 for (unsigned i = 0; i < conf->num_queues; i++) {
1478 s->vq_aio_context[i] = ctx;
1479 }
1480 }
1481
1482 return true;
1483 }
1484
1485 /* Context: BQL held */
virtio_blk_vq_aio_context_cleanup(VirtIOBlock * s)1486 static void virtio_blk_vq_aio_context_cleanup(VirtIOBlock *s)
1487 {
1488 VirtIOBlkConf *conf = &s->conf;
1489
1490 assert(!s->ioeventfd_started);
1491
1492 if (conf->iothread_vq_mapping_list) {
1493 iothread_vq_mapping_cleanup(conf->iothread_vq_mapping_list);
1494 }
1495
1496 if (conf->iothread) {
1497 object_unref(OBJECT(conf->iothread));
1498 }
1499
1500 g_free(s->vq_aio_context);
1501 s->vq_aio_context = NULL;
1502 }
1503
1504 /* Context: BQL held */
virtio_blk_start_ioeventfd(VirtIODevice * vdev)1505 static int virtio_blk_start_ioeventfd(VirtIODevice *vdev)
1506 {
1507 VirtIOBlock *s = VIRTIO_BLK(vdev);
1508 BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(s)));
1509 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
1510 unsigned i;
1511 unsigned nvqs = s->conf.num_queues;
1512 Error *local_err = NULL;
1513 int r;
1514
1515 if (s->ioeventfd_started || s->ioeventfd_starting) {
1516 return 0;
1517 }
1518
1519 s->ioeventfd_starting = true;
1520
1521 /* Set up guest notifier (irq) */
1522 r = k->set_guest_notifiers(qbus->parent, nvqs, true);
1523 if (r != 0) {
1524 error_report("virtio-blk failed to set guest notifier (%d), "
1525 "ensure -accel kvm is set.", r);
1526 goto fail_guest_notifiers;
1527 }
1528
1529 /*
1530 * Batch all the host notifiers in a single transaction to avoid
1531 * quadratic time complexity in address_space_update_ioeventfds().
1532 */
1533 memory_region_transaction_begin();
1534
1535 /* Set up virtqueue notify */
1536 for (i = 0; i < nvqs; i++) {
1537 r = virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, true);
1538 if (r != 0) {
1539 int j = i;
1540
1541 fprintf(stderr, "virtio-blk failed to set host notifier (%d)\n", r);
1542 while (i--) {
1543 virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, false);
1544 }
1545
1546 /*
1547 * The transaction expects the ioeventfds to be open when it
1548 * commits. Do it now, before the cleanup loop.
1549 */
1550 memory_region_transaction_commit();
1551
1552 while (j--) {
1553 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), j);
1554 }
1555 goto fail_host_notifiers;
1556 }
1557 }
1558
1559 memory_region_transaction_commit();
1560
1561 /*
1562 * Try to change the AioContext so that block jobs and other operations can
1563 * co-locate their activity in the same AioContext. If it fails, nevermind.
1564 */
1565 assert(nvqs > 0); /* enforced during ->realize() */
1566 r = blk_set_aio_context(s->conf.conf.blk, s->vq_aio_context[0],
1567 &local_err);
1568 if (r < 0) {
1569 warn_report_err(local_err);
1570 }
1571
1572 /*
1573 * These fields must be visible to the IOThread when it processes the
1574 * virtqueue, otherwise it will think ioeventfd has not started yet.
1575 *
1576 * Make sure ->ioeventfd_started is false when blk_set_aio_context() is
1577 * called above so that draining does not cause the host notifier to be
1578 * detached/attached prematurely.
1579 */
1580 s->ioeventfd_starting = false;
1581 s->ioeventfd_started = true;
1582 smp_wmb(); /* paired with aio_notify_accept() on the read side */
1583
1584 /*
1585 * Get this show started by hooking up our callbacks. If drained now,
1586 * virtio_blk_drained_end() will do this later.
1587 * Attaching the notifier also kicks the virtqueues, processing any requests
1588 * they may already have.
1589 */
1590 if (!blk_in_drain(s->conf.conf.blk)) {
1591 virtio_blk_ioeventfd_attach(s);
1592 }
1593 return 0;
1594
1595 fail_host_notifiers:
1596 k->set_guest_notifiers(qbus->parent, nvqs, false);
1597 fail_guest_notifiers:
1598 s->ioeventfd_disabled = true;
1599 s->ioeventfd_starting = false;
1600 return -ENOSYS;
1601 }
1602
1603 /* Stop notifications for new requests from guest.
1604 *
1605 * Context: BH in IOThread
1606 */
virtio_blk_ioeventfd_stop_vq_bh(void * opaque)1607 static void virtio_blk_ioeventfd_stop_vq_bh(void *opaque)
1608 {
1609 VirtQueue *vq = opaque;
1610 EventNotifier *host_notifier = virtio_queue_get_host_notifier(vq);
1611
1612 virtio_queue_aio_detach_host_notifier(vq, qemu_get_current_aio_context());
1613
1614 /*
1615 * Test and clear notifier after disabling event, in case poll callback
1616 * didn't have time to run.
1617 */
1618 virtio_queue_host_notifier_read(host_notifier);
1619 }
1620
1621 /* Context: BQL held */
virtio_blk_stop_ioeventfd(VirtIODevice * vdev)1622 static void virtio_blk_stop_ioeventfd(VirtIODevice *vdev)
1623 {
1624 VirtIOBlock *s = VIRTIO_BLK(vdev);
1625 BusState *qbus = qdev_get_parent_bus(DEVICE(s));
1626 VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
1627 unsigned i;
1628 unsigned nvqs = s->conf.num_queues;
1629
1630 if (!s->ioeventfd_started || s->ioeventfd_stopping) {
1631 return;
1632 }
1633
1634 /* Better luck next time. */
1635 if (s->ioeventfd_disabled) {
1636 s->ioeventfd_disabled = false;
1637 s->ioeventfd_started = false;
1638 return;
1639 }
1640 s->ioeventfd_stopping = true;
1641
1642 if (!blk_in_drain(s->conf.conf.blk)) {
1643 for (i = 0; i < nvqs; i++) {
1644 VirtQueue *vq = virtio_get_queue(vdev, i);
1645 AioContext *ctx = s->vq_aio_context[i];
1646
1647 aio_wait_bh_oneshot(ctx, virtio_blk_ioeventfd_stop_vq_bh, vq);
1648 }
1649 }
1650
1651 /*
1652 * Batch all the host notifiers in a single transaction to avoid
1653 * quadratic time complexity in address_space_update_ioeventfds().
1654 */
1655 memory_region_transaction_begin();
1656
1657 for (i = 0; i < nvqs; i++) {
1658 virtio_bus_set_host_notifier(VIRTIO_BUS(qbus), i, false);
1659 }
1660
1661 /*
1662 * The transaction expects the ioeventfds to be open when it
1663 * commits. Do it now, before the cleanup loop.
1664 */
1665 memory_region_transaction_commit();
1666
1667 for (i = 0; i < nvqs; i++) {
1668 virtio_bus_cleanup_host_notifier(VIRTIO_BUS(qbus), i);
1669 }
1670
1671 /*
1672 * Set ->ioeventfd_started to false before draining so that host notifiers
1673 * are not detached/attached anymore.
1674 */
1675 s->ioeventfd_started = false;
1676
1677 /* Wait for virtio_blk_dma_restart_bh() and in flight I/O to complete */
1678 blk_drain(s->conf.conf.blk);
1679
1680 /*
1681 * Try to switch bs back to the QEMU main loop. If other users keep the
1682 * BlockBackend in the iothread, that's ok
1683 */
1684 blk_set_aio_context(s->conf.conf.blk, qemu_get_aio_context(), NULL);
1685
1686 /* Clean up guest notifier (irq) */
1687 k->set_guest_notifiers(qbus->parent, nvqs, false);
1688
1689 s->ioeventfd_stopping = false;
1690 }
1691
virtio_blk_device_realize(DeviceState * dev,Error ** errp)1692 static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
1693 {
1694 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1695 VirtIOBlock *s = VIRTIO_BLK(dev);
1696 VirtIOBlkConf *conf = &s->conf;
1697 BlockDriverState *bs;
1698 Error *err = NULL;
1699 unsigned i;
1700
1701 if (!conf->conf.blk) {
1702 error_setg(errp, "drive property not set");
1703 return;
1704 }
1705 if (!blk_is_inserted(conf->conf.blk)) {
1706 error_setg(errp, "Device needs media, but drive is empty");
1707 return;
1708 }
1709 if (conf->num_queues == VIRTIO_BLK_AUTO_NUM_QUEUES) {
1710 conf->num_queues = 1;
1711 }
1712 if (!conf->num_queues) {
1713 error_setg(errp, "num-queues property must be larger than 0");
1714 return;
1715 }
1716 if (conf->queue_size <= 2) {
1717 error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1718 "must be > 2", conf->queue_size);
1719 return;
1720 }
1721 if (!is_power_of_2(conf->queue_size) ||
1722 conf->queue_size > VIRTQUEUE_MAX_SIZE) {
1723 error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1724 "must be a power of 2 (max %d)",
1725 conf->queue_size, VIRTQUEUE_MAX_SIZE);
1726 return;
1727 }
1728
1729 if (!blkconf_apply_backend_options(&conf->conf,
1730 !blk_supports_write_perm(conf->conf.blk),
1731 true, errp)) {
1732 return;
1733 }
1734 s->original_wce = blk_enable_write_cache(conf->conf.blk);
1735 if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) {
1736 return;
1737 }
1738
1739 if (!blkconf_blocksizes(&conf->conf, errp)) {
1740 return;
1741 }
1742
1743 bs = blk_bs(conf->conf.blk);
1744 if (bs->bl.zoned != BLK_Z_NONE) {
1745 virtio_add_feature(&s->host_features, VIRTIO_BLK_F_ZONED);
1746 if (bs->bl.zoned == BLK_Z_HM) {
1747 virtio_clear_feature(&s->host_features, VIRTIO_BLK_F_DISCARD);
1748 }
1749 }
1750
1751 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) &&
1752 (!conf->max_discard_sectors ||
1753 conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1754 error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")"
1755 ", must be between 1 and %d",
1756 conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS);
1757 return;
1758 }
1759
1760 if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) &&
1761 (!conf->max_write_zeroes_sectors ||
1762 conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1763 error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32
1764 "), must be between 1 and %d",
1765 conf->max_write_zeroes_sectors,
1766 (int)BDRV_REQUEST_MAX_SECTORS);
1767 return;
1768 }
1769
1770 s->config_size = virtio_get_config_size(&virtio_blk_cfg_size_params,
1771 s->host_features);
1772 virtio_init(vdev, VIRTIO_ID_BLOCK, s->config_size);
1773
1774 qemu_mutex_init(&s->rq_lock);
1775
1776 s->blk = conf->conf.blk;
1777 s->rq = NULL;
1778 s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1;
1779
1780 for (i = 0; i < conf->num_queues; i++) {
1781 virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output);
1782 }
1783 qemu_coroutine_inc_pool_size(conf->num_queues * conf->queue_size / 2);
1784
1785 /* Don't start ioeventfd if transport does not support notifiers. */
1786 if (!virtio_device_ioeventfd_enabled(vdev)) {
1787 s->ioeventfd_disabled = true;
1788 }
1789
1790 virtio_blk_vq_aio_context_init(s, &err);
1791 if (err != NULL) {
1792 error_propagate(errp, err);
1793 for (i = 0; i < conf->num_queues; i++) {
1794 virtio_del_queue(vdev, i);
1795 }
1796 virtio_cleanup(vdev);
1797 return;
1798 }
1799
1800 /*
1801 * This must be after virtio_init() so virtio_blk_dma_restart_cb() gets
1802 * called after ->start_ioeventfd() has already set blk's AioContext.
1803 */
1804 s->change =
1805 qdev_add_vm_change_state_handler(dev, virtio_blk_dma_restart_cb, s);
1806
1807 blk_ram_registrar_init(&s->blk_ram_registrar, s->blk);
1808 blk_set_dev_ops(s->blk, &virtio_block_ops, s);
1809
1810 blk_iostatus_enable(s->blk);
1811
1812 add_boot_device_lchs(dev, "/disk@0,0",
1813 conf->conf.lcyls,
1814 conf->conf.lheads,
1815 conf->conf.lsecs);
1816 }
1817
virtio_blk_device_unrealize(DeviceState * dev)1818 static void virtio_blk_device_unrealize(DeviceState *dev)
1819 {
1820 VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1821 VirtIOBlock *s = VIRTIO_BLK(dev);
1822 VirtIOBlkConf *conf = &s->conf;
1823 unsigned i;
1824
1825 blk_drain(s->blk);
1826 del_boot_device_lchs(dev, "/disk@0,0");
1827 virtio_blk_vq_aio_context_cleanup(s);
1828 for (i = 0; i < conf->num_queues; i++) {
1829 virtio_del_queue(vdev, i);
1830 }
1831 qemu_coroutine_dec_pool_size(conf->num_queues * conf->queue_size / 2);
1832 qemu_mutex_destroy(&s->rq_lock);
1833 blk_ram_registrar_destroy(&s->blk_ram_registrar);
1834 qemu_del_vm_change_state_handler(s->change);
1835 blockdev_mark_auto_del(s->blk);
1836 virtio_cleanup(vdev);
1837 }
1838
virtio_blk_instance_init(Object * obj)1839 static void virtio_blk_instance_init(Object *obj)
1840 {
1841 VirtIOBlock *s = VIRTIO_BLK(obj);
1842
1843 device_add_bootindex_property(obj, &s->conf.conf.bootindex,
1844 "bootindex", "/disk@0,0",
1845 DEVICE(obj));
1846 }
1847
1848 static const VMStateDescription vmstate_virtio_blk = {
1849 .name = "virtio-blk",
1850 .minimum_version_id = 2,
1851 .version_id = 2,
1852 .fields = (const VMStateField[]) {
1853 VMSTATE_VIRTIO_DEVICE,
1854 VMSTATE_END_OF_LIST()
1855 },
1856 };
1857
1858 static const Property virtio_blk_properties[] = {
1859 DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf),
1860 DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf),
1861 DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf),
1862 DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial),
1863 DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features,
1864 VIRTIO_BLK_F_CONFIG_WCE, true),
1865 DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
1866 true),
1867 DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues,
1868 VIRTIO_BLK_AUTO_NUM_QUEUES),
1869 DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256),
1870 DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true),
1871 DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD,
1872 IOThread *),
1873 DEFINE_PROP_IOTHREAD_VQ_MAPPING_LIST("iothread-vq-mapping", VirtIOBlock,
1874 conf.iothread_vq_mapping_list),
1875 DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features,
1876 VIRTIO_BLK_F_DISCARD, true),
1877 DEFINE_PROP_BOOL("report-discard-granularity", VirtIOBlock,
1878 conf.report_discard_granularity, true),
1879 DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features,
1880 VIRTIO_BLK_F_WRITE_ZEROES, true),
1881 DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock,
1882 conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS),
1883 DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock,
1884 conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS),
1885 DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock,
1886 conf.x_enable_wce_if_config_wce, true),
1887 };
1888
virtio_blk_class_init(ObjectClass * klass,void * data)1889 static void virtio_blk_class_init(ObjectClass *klass, void *data)
1890 {
1891 DeviceClass *dc = DEVICE_CLASS(klass);
1892 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
1893
1894 device_class_set_props(dc, virtio_blk_properties);
1895 dc->vmsd = &vmstate_virtio_blk;
1896 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1897 vdc->realize = virtio_blk_device_realize;
1898 vdc->unrealize = virtio_blk_device_unrealize;
1899 vdc->get_config = virtio_blk_update_config;
1900 vdc->set_config = virtio_blk_set_config;
1901 vdc->get_features = virtio_blk_get_features;
1902 vdc->set_status = virtio_blk_set_status;
1903 vdc->reset = virtio_blk_reset;
1904 vdc->save = virtio_blk_save_device;
1905 vdc->load = virtio_blk_load_device;
1906 vdc->start_ioeventfd = virtio_blk_start_ioeventfd;
1907 vdc->stop_ioeventfd = virtio_blk_stop_ioeventfd;
1908 }
1909
1910 static const TypeInfo virtio_blk_info = {
1911 .name = TYPE_VIRTIO_BLK,
1912 .parent = TYPE_VIRTIO_DEVICE,
1913 .instance_size = sizeof(VirtIOBlock),
1914 .instance_init = virtio_blk_instance_init,
1915 .class_init = virtio_blk_class_init,
1916 .class_size = sizeof(VirtIOBlkClass),
1917 };
1918
virtio_register_types(void)1919 static void virtio_register_types(void)
1920 {
1921 type_register_static(&virtio_blk_info);
1922 }
1923
1924 type_init(virtio_register_types)
1925