xref: /openbmc/qemu/hw/block/virtio-blk.c (revision d19630d2)
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 "sysemu/blockdev.h"
26 #include "sysemu/block-ram-registrar.h"
27 #include "sysemu/sysemu.h"
28 #include "sysemu/runstate.h"
29 #include "hw/virtio/virtio-blk.h"
30 #include "dataplane/virtio-blk.h"
31 #include "scsi/constants.h"
32 #ifdef __linux__
33 # include <scsi/sg.h>
34 #endif
35 #include "hw/virtio/virtio-bus.h"
36 #include "migration/qemu-file-types.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_init_request(VirtIOBlock *s, VirtQueue *vq,
42                                     VirtIOBlockReq *req)
43 {
44     req->dev = s;
45     req->vq = vq;
46     req->qiov.size = 0;
47     req->in_len = 0;
48     req->next = NULL;
49     req->mr_next = NULL;
50 }
51 
52 static void virtio_blk_free_request(VirtIOBlockReq *req)
53 {
54     g_free(req);
55 }
56 
57 static void virtio_blk_req_complete(VirtIOBlockReq *req, unsigned char status)
58 {
59     VirtIOBlock *s = req->dev;
60     VirtIODevice *vdev = VIRTIO_DEVICE(s);
61 
62     trace_virtio_blk_req_complete(vdev, req, status);
63 
64     stb_p(&req->in->status, status);
65     iov_discard_undo(&req->inhdr_undo);
66     iov_discard_undo(&req->outhdr_undo);
67     virtqueue_push(req->vq, &req->elem, req->in_len);
68     if (s->dataplane_started && !s->dataplane_disabled) {
69         virtio_blk_data_plane_notify(s->dataplane, req->vq);
70     } else {
71         virtio_notify(vdev, req->vq);
72     }
73 }
74 
75 static int virtio_blk_handle_rw_error(VirtIOBlockReq *req, int error,
76     bool is_read, bool acct_failed)
77 {
78     VirtIOBlock *s = req->dev;
79     BlockErrorAction action = blk_get_error_action(s->blk, is_read, error);
80 
81     if (action == BLOCK_ERROR_ACTION_STOP) {
82         /* Break the link as the next request is going to be parsed from the
83          * ring again. Otherwise we may end up doing a double completion! */
84         req->mr_next = NULL;
85 
86         WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
87             req->next = s->rq;
88             s->rq = req;
89         }
90     } else if (action == BLOCK_ERROR_ACTION_REPORT) {
91         virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
92         if (acct_failed) {
93             block_acct_failed(blk_get_stats(s->blk), &req->acct);
94         }
95         virtio_blk_free_request(req);
96     }
97 
98     blk_error_action(s->blk, action, is_read, error);
99     return action != BLOCK_ERROR_ACTION_IGNORE;
100 }
101 
102 static void virtio_blk_rw_complete(void *opaque, int ret)
103 {
104     VirtIOBlockReq *next = opaque;
105     VirtIOBlock *s = next->dev;
106     VirtIODevice *vdev = VIRTIO_DEVICE(s);
107 
108     while (next) {
109         VirtIOBlockReq *req = next;
110         next = req->mr_next;
111         trace_virtio_blk_rw_complete(vdev, req, ret);
112 
113         if (req->qiov.nalloc != -1) {
114             /* If nalloc is != -1 req->qiov is a local copy of the original
115              * external iovec. It was allocated in submit_requests to be
116              * able to merge requests. */
117             qemu_iovec_destroy(&req->qiov);
118         }
119 
120         if (ret) {
121             int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type);
122             bool is_read = !(p & VIRTIO_BLK_T_OUT);
123             /* Note that memory may be dirtied on read failure.  If the
124              * virtio request is not completed here, as is the case for
125              * BLOCK_ERROR_ACTION_STOP, the memory may not be copied
126              * correctly during live migration.  While this is ugly,
127              * it is acceptable because the device is free to write to
128              * the memory until the request is completed (which will
129              * happen on the other side of the migration).
130              */
131             if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) {
132                 continue;
133             }
134         }
135 
136         virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
137         block_acct_done(blk_get_stats(s->blk), &req->acct);
138         virtio_blk_free_request(req);
139     }
140 }
141 
142 static void virtio_blk_flush_complete(void *opaque, int ret)
143 {
144     VirtIOBlockReq *req = opaque;
145     VirtIOBlock *s = req->dev;
146 
147     if (ret && virtio_blk_handle_rw_error(req, -ret, 0, true)) {
148         return;
149     }
150 
151     virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
152     block_acct_done(blk_get_stats(s->blk), &req->acct);
153     virtio_blk_free_request(req);
154 }
155 
156 static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret)
157 {
158     VirtIOBlockReq *req = opaque;
159     VirtIOBlock *s = req->dev;
160     bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) &
161                             ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES;
162 
163     if (ret && virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) {
164         return;
165     }
166 
167     virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
168     if (is_write_zeroes) {
169         block_acct_done(blk_get_stats(s->blk), &req->acct);
170     }
171     virtio_blk_free_request(req);
172 }
173 
174 #ifdef __linux__
175 
176 typedef struct {
177     VirtIOBlockReq *req;
178     struct sg_io_hdr hdr;
179 } VirtIOBlockIoctlReq;
180 
181 static void virtio_blk_ioctl_complete(void *opaque, int status)
182 {
183     VirtIOBlockIoctlReq *ioctl_req = opaque;
184     VirtIOBlockReq *req = ioctl_req->req;
185     VirtIOBlock *s = req->dev;
186     VirtIODevice *vdev = VIRTIO_DEVICE(s);
187     struct virtio_scsi_inhdr *scsi;
188     struct sg_io_hdr *hdr;
189 
190     scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base;
191 
192     if (status) {
193         status = VIRTIO_BLK_S_UNSUPP;
194         virtio_stl_p(vdev, &scsi->errors, 255);
195         goto out;
196     }
197 
198     hdr = &ioctl_req->hdr;
199     /*
200      * From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi)
201      * clear the masked_status field [hence status gets cleared too, see
202      * block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED
203      * status has occurred.  However they do set DRIVER_SENSE in driver_status
204      * field. Also a (sb_len_wr > 0) indicates there is a sense buffer.
205      */
206     if (hdr->status == 0 && hdr->sb_len_wr > 0) {
207         hdr->status = CHECK_CONDITION;
208     }
209 
210     virtio_stl_p(vdev, &scsi->errors,
211                  hdr->status | (hdr->msg_status << 8) |
212                  (hdr->host_status << 16) | (hdr->driver_status << 24));
213     virtio_stl_p(vdev, &scsi->residual, hdr->resid);
214     virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr);
215     virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len);
216 
217 out:
218     virtio_blk_req_complete(req, status);
219     virtio_blk_free_request(req);
220     g_free(ioctl_req);
221 }
222 
223 #endif
224 
225 static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq)
226 {
227     VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq));
228 
229     if (req) {
230         virtio_blk_init_request(s, vq, req);
231     }
232     return req;
233 }
234 
235 static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
236 {
237     int status = VIRTIO_BLK_S_OK;
238     struct virtio_scsi_inhdr *scsi = NULL;
239     VirtIOBlock *blk = req->dev;
240     VirtIODevice *vdev = VIRTIO_DEVICE(blk);
241     VirtQueueElement *elem = &req->elem;
242 
243 #ifdef __linux__
244     int i;
245     VirtIOBlockIoctlReq *ioctl_req;
246     BlockAIOCB *acb;
247 #endif
248 
249     /*
250      * We require at least one output segment each for the virtio_blk_outhdr
251      * and the SCSI command block.
252      *
253      * We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr
254      * and the sense buffer pointer in the input segments.
255      */
256     if (elem->out_num < 2 || elem->in_num < 3) {
257         status = VIRTIO_BLK_S_IOERR;
258         goto fail;
259     }
260 
261     /*
262      * The scsi inhdr is placed in the second-to-last input segment, just
263      * before the regular inhdr.
264      */
265     scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base;
266 
267     if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) {
268         status = VIRTIO_BLK_S_UNSUPP;
269         goto fail;
270     }
271 
272     /*
273      * No support for bidirection commands yet.
274      */
275     if (elem->out_num > 2 && elem->in_num > 3) {
276         status = VIRTIO_BLK_S_UNSUPP;
277         goto fail;
278     }
279 
280 #ifdef __linux__
281     ioctl_req = g_new0(VirtIOBlockIoctlReq, 1);
282     ioctl_req->req = req;
283     ioctl_req->hdr.interface_id = 'S';
284     ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len;
285     ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base;
286     ioctl_req->hdr.dxfer_len = 0;
287 
288     if (elem->out_num > 2) {
289         /*
290          * If there are more than the minimally required 2 output segments
291          * there is write payload starting from the third iovec.
292          */
293         ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV;
294         ioctl_req->hdr.iovec_count = elem->out_num - 2;
295 
296         for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
297             ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len;
298         }
299 
300         ioctl_req->hdr.dxferp = elem->out_sg + 2;
301 
302     } else if (elem->in_num > 3) {
303         /*
304          * If we have more than 3 input segments the guest wants to actually
305          * read data.
306          */
307         ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV;
308         ioctl_req->hdr.iovec_count = elem->in_num - 3;
309         for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
310             ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len;
311         }
312 
313         ioctl_req->hdr.dxferp = elem->in_sg;
314     } else {
315         /*
316          * Some SCSI commands don't actually transfer any data.
317          */
318         ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE;
319     }
320 
321     ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base;
322     ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len;
323 
324     acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
325                         virtio_blk_ioctl_complete, ioctl_req);
326     if (!acb) {
327         g_free(ioctl_req);
328         status = VIRTIO_BLK_S_UNSUPP;
329         goto fail;
330     }
331     return -EINPROGRESS;
332 #else
333     abort();
334 #endif
335 
336 fail:
337     /* Just put anything nonzero so that the ioctl fails in the guest.  */
338     if (scsi) {
339         virtio_stl_p(vdev, &scsi->errors, 255);
340     }
341     return status;
342 }
343 
344 static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
345 {
346     int status;
347 
348     status = virtio_blk_handle_scsi_req(req);
349     if (status != -EINPROGRESS) {
350         virtio_blk_req_complete(req, status);
351         virtio_blk_free_request(req);
352     }
353 }
354 
355 static inline void submit_requests(VirtIOBlock *s, MultiReqBuffer *mrb,
356                                    int start, int num_reqs, int niov)
357 {
358     BlockBackend *blk = s->blk;
359     QEMUIOVector *qiov = &mrb->reqs[start]->qiov;
360     int64_t sector_num = mrb->reqs[start]->sector_num;
361     bool is_write = mrb->is_write;
362     BdrvRequestFlags flags = 0;
363 
364     if (num_reqs > 1) {
365         int i;
366         struct iovec *tmp_iov = qiov->iov;
367         int tmp_niov = qiov->niov;
368 
369         /* mrb->reqs[start]->qiov was initialized from external so we can't
370          * modify it here. We need to initialize it locally and then add the
371          * external iovecs. */
372         qemu_iovec_init(qiov, niov);
373 
374         for (i = 0; i < tmp_niov; i++) {
375             qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len);
376         }
377 
378         for (i = start + 1; i < start + num_reqs; i++) {
379             qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0,
380                               mrb->reqs[i]->qiov.size);
381             mrb->reqs[i - 1]->mr_next = mrb->reqs[i];
382         }
383 
384         trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev),
385                                          mrb, start, num_reqs,
386                                          sector_num << BDRV_SECTOR_BITS,
387                                          qiov->size, is_write);
388         block_acct_merge_done(blk_get_stats(blk),
389                               is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ,
390                               num_reqs - 1);
391     }
392 
393     if (blk_ram_registrar_ok(&s->blk_ram_registrar)) {
394         flags |= BDRV_REQ_REGISTERED_BUF;
395     }
396 
397     if (is_write) {
398         blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov,
399                         flags, virtio_blk_rw_complete,
400                         mrb->reqs[start]);
401     } else {
402         blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov,
403                        flags, virtio_blk_rw_complete,
404                        mrb->reqs[start]);
405     }
406 }
407 
408 static int multireq_compare(const void *a, const void *b)
409 {
410     const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a,
411                          *req2 = *(VirtIOBlockReq **)b;
412 
413     /*
414      * Note that we can't simply subtract sector_num1 from sector_num2
415      * here as that could overflow the return value.
416      */
417     if (req1->sector_num > req2->sector_num) {
418         return 1;
419     } else if (req1->sector_num < req2->sector_num) {
420         return -1;
421     } else {
422         return 0;
423     }
424 }
425 
426 static void virtio_blk_submit_multireq(VirtIOBlock *s, MultiReqBuffer *mrb)
427 {
428     int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0;
429     uint32_t max_transfer;
430     int64_t sector_num = 0;
431 
432     if (mrb->num_reqs == 1) {
433         submit_requests(s, mrb, 0, 1, -1);
434         mrb->num_reqs = 0;
435         return;
436     }
437 
438     max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk);
439 
440     qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),
441           &multireq_compare);
442 
443     for (i = 0; i < mrb->num_reqs; i++) {
444         VirtIOBlockReq *req = mrb->reqs[i];
445         if (num_reqs > 0) {
446             /*
447              * NOTE: We cannot merge the requests in below situations:
448              * 1. requests are not sequential
449              * 2. merge would exceed maximum number of IOVs
450              * 3. merge would exceed maximum transfer length of backend device
451              */
452             if (sector_num + nb_sectors != req->sector_num ||
453                 niov > blk_get_max_iov(s->blk) - req->qiov.niov ||
454                 req->qiov.size > max_transfer ||
455                 nb_sectors > (max_transfer -
456                               req->qiov.size) / BDRV_SECTOR_SIZE) {
457                 submit_requests(s, mrb, start, num_reqs, niov);
458                 num_reqs = 0;
459             }
460         }
461 
462         if (num_reqs == 0) {
463             sector_num = req->sector_num;
464             nb_sectors = niov = 0;
465             start = i;
466         }
467 
468         nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE;
469         niov += req->qiov.niov;
470         num_reqs++;
471     }
472 
473     submit_requests(s, mrb, start, num_reqs, niov);
474     mrb->num_reqs = 0;
475 }
476 
477 static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
478 {
479     VirtIOBlock *s = req->dev;
480 
481     block_acct_start(blk_get_stats(s->blk), &req->acct, 0,
482                      BLOCK_ACCT_FLUSH);
483 
484     /*
485      * Make sure all outstanding writes are posted to the backing device.
486      */
487     if (mrb->is_write && mrb->num_reqs > 0) {
488         virtio_blk_submit_multireq(s, mrb);
489     }
490     blk_aio_flush(s->blk, virtio_blk_flush_complete, req);
491 }
492 
493 static bool virtio_blk_sect_range_ok(VirtIOBlock *dev,
494                                      uint64_t sector, size_t size)
495 {
496     uint64_t nb_sectors = size >> BDRV_SECTOR_BITS;
497     uint64_t total_sectors;
498 
499     if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
500         return false;
501     }
502     if (sector & dev->sector_mask) {
503         return false;
504     }
505     if (size % dev->conf.conf.logical_block_size) {
506         return false;
507     }
508     blk_get_geometry(dev->blk, &total_sectors);
509     if (sector > total_sectors || nb_sectors > total_sectors - sector) {
510         return false;
511     }
512     return true;
513 }
514 
515 static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req,
516     struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes)
517 {
518     VirtIOBlock *s = req->dev;
519     VirtIODevice *vdev = VIRTIO_DEVICE(s);
520     uint64_t sector;
521     uint32_t num_sectors, flags, max_sectors;
522     uint8_t err_status;
523     int bytes;
524 
525     sector = virtio_ldq_p(vdev, &dwz_hdr->sector);
526     num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors);
527     flags = virtio_ldl_p(vdev, &dwz_hdr->flags);
528     max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors :
529                   s->conf.max_discard_sectors;
530 
531     /*
532      * max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check
533      * make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in
534      * the integer variable.
535      */
536     if (unlikely(num_sectors > max_sectors)) {
537         err_status = VIRTIO_BLK_S_IOERR;
538         goto err;
539     }
540 
541     bytes = num_sectors << BDRV_SECTOR_BITS;
542 
543     if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) {
544         err_status = VIRTIO_BLK_S_IOERR;
545         goto err;
546     }
547 
548     /*
549      * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard
550      * and write zeroes commands if any unknown flag is set.
551      */
552     if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
553         err_status = VIRTIO_BLK_S_UNSUPP;
554         goto err;
555     }
556 
557     if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */
558         int blk_aio_flags = 0;
559 
560         if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
561             blk_aio_flags |= BDRV_REQ_MAY_UNMAP;
562         }
563 
564         block_acct_start(blk_get_stats(s->blk), &req->acct, bytes,
565                          BLOCK_ACCT_WRITE);
566 
567         blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS,
568                               bytes, blk_aio_flags,
569                               virtio_blk_discard_write_zeroes_complete, req);
570     } else { /* VIRTIO_BLK_T_DISCARD */
571         /*
572          * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for
573          * discard commands if the unmap flag is set.
574          */
575         if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
576             err_status = VIRTIO_BLK_S_UNSUPP;
577             goto err;
578         }
579 
580         blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes,
581                          virtio_blk_discard_write_zeroes_complete, req);
582     }
583 
584     return VIRTIO_BLK_S_OK;
585 
586 err:
587     if (is_write_zeroes) {
588         block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE);
589     }
590     return err_status;
591 }
592 
593 typedef struct ZoneCmdData {
594     VirtIOBlockReq *req;
595     struct iovec *in_iov;
596     unsigned in_num;
597     union {
598         struct {
599             unsigned int nr_zones;
600             BlockZoneDescriptor *zones;
601         } zone_report_data;
602         struct {
603             int64_t offset;
604         } zone_append_data;
605     };
606 } ZoneCmdData;
607 
608 /*
609  * check zoned_request: error checking before issuing requests. If all checks
610  * passed, return true.
611  * append: true if only zone append requests issued.
612  */
613 static bool check_zoned_request(VirtIOBlock *s, int64_t offset, int64_t len,
614                              bool append, uint8_t *status) {
615     BlockDriverState *bs = blk_bs(s->blk);
616     int index;
617 
618     if (!virtio_has_feature(s->host_features, VIRTIO_BLK_F_ZONED)) {
619         *status = VIRTIO_BLK_S_UNSUPP;
620         return false;
621     }
622 
623     if (offset < 0 || len < 0 || len > (bs->total_sectors << BDRV_SECTOR_BITS)
624         || offset > (bs->total_sectors << BDRV_SECTOR_BITS) - len) {
625         *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
626         return false;
627     }
628 
629     if (append) {
630         if (bs->bl.write_granularity) {
631             if ((offset % bs->bl.write_granularity) != 0) {
632                 *status = VIRTIO_BLK_S_ZONE_UNALIGNED_WP;
633                 return false;
634             }
635         }
636 
637         index = offset / bs->bl.zone_size;
638         if (BDRV_ZT_IS_CONV(bs->wps->wp[index])) {
639             *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
640             return false;
641         }
642 
643         if (len / 512 > bs->bl.max_append_sectors) {
644             if (bs->bl.max_append_sectors == 0) {
645                 *status = VIRTIO_BLK_S_UNSUPP;
646             } else {
647                 *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
648             }
649             return false;
650         }
651     }
652     return true;
653 }
654 
655 static void virtio_blk_zone_report_complete(void *opaque, int ret)
656 {
657     ZoneCmdData *data = opaque;
658     VirtIOBlockReq *req = data->req;
659     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
660     struct iovec *in_iov = data->in_iov;
661     unsigned in_num = data->in_num;
662     int64_t zrp_size, n, j = 0;
663     int64_t nz = data->zone_report_data.nr_zones;
664     int8_t err_status = VIRTIO_BLK_S_OK;
665 
666     trace_virtio_blk_zone_report_complete(vdev, req, nz, ret);
667     if (ret) {
668         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
669         goto out;
670     }
671 
672     struct virtio_blk_zone_report zrp_hdr = (struct virtio_blk_zone_report) {
673         .nr_zones = cpu_to_le64(nz),
674     };
675     zrp_size = sizeof(struct virtio_blk_zone_report)
676                + sizeof(struct virtio_blk_zone_descriptor) * nz;
677     n = iov_from_buf(in_iov, in_num, 0, &zrp_hdr, sizeof(zrp_hdr));
678     if (n != sizeof(zrp_hdr)) {
679         virtio_error(vdev, "Driver provided input buffer that is too small!");
680         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
681         goto out;
682     }
683 
684     for (size_t i = sizeof(zrp_hdr); i < zrp_size;
685         i += sizeof(struct virtio_blk_zone_descriptor), ++j) {
686         struct virtio_blk_zone_descriptor desc =
687             (struct virtio_blk_zone_descriptor) {
688                 .z_start = cpu_to_le64(data->zone_report_data.zones[j].start
689                     >> BDRV_SECTOR_BITS),
690                 .z_cap = cpu_to_le64(data->zone_report_data.zones[j].cap
691                     >> BDRV_SECTOR_BITS),
692                 .z_wp = cpu_to_le64(data->zone_report_data.zones[j].wp
693                     >> BDRV_SECTOR_BITS),
694         };
695 
696         switch (data->zone_report_data.zones[j].type) {
697         case BLK_ZT_CONV:
698             desc.z_type = VIRTIO_BLK_ZT_CONV;
699             break;
700         case BLK_ZT_SWR:
701             desc.z_type = VIRTIO_BLK_ZT_SWR;
702             break;
703         case BLK_ZT_SWP:
704             desc.z_type = VIRTIO_BLK_ZT_SWP;
705             break;
706         default:
707             g_assert_not_reached();
708         }
709 
710         switch (data->zone_report_data.zones[j].state) {
711         case BLK_ZS_RDONLY:
712             desc.z_state = VIRTIO_BLK_ZS_RDONLY;
713             break;
714         case BLK_ZS_OFFLINE:
715             desc.z_state = VIRTIO_BLK_ZS_OFFLINE;
716             break;
717         case BLK_ZS_EMPTY:
718             desc.z_state = VIRTIO_BLK_ZS_EMPTY;
719             break;
720         case BLK_ZS_CLOSED:
721             desc.z_state = VIRTIO_BLK_ZS_CLOSED;
722             break;
723         case BLK_ZS_FULL:
724             desc.z_state = VIRTIO_BLK_ZS_FULL;
725             break;
726         case BLK_ZS_EOPEN:
727             desc.z_state = VIRTIO_BLK_ZS_EOPEN;
728             break;
729         case BLK_ZS_IOPEN:
730             desc.z_state = VIRTIO_BLK_ZS_IOPEN;
731             break;
732         case BLK_ZS_NOT_WP:
733             desc.z_state = VIRTIO_BLK_ZS_NOT_WP;
734             break;
735         default:
736             g_assert_not_reached();
737         }
738 
739         /* TODO: it takes O(n^2) time complexity. Optimizations required. */
740         n = iov_from_buf(in_iov, in_num, i, &desc, sizeof(desc));
741         if (n != sizeof(desc)) {
742             virtio_error(vdev, "Driver provided input buffer "
743                                "for descriptors that is too small!");
744             err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
745         }
746     }
747 
748 out:
749     virtio_blk_req_complete(req, err_status);
750     virtio_blk_free_request(req);
751     g_free(data->zone_report_data.zones);
752     g_free(data);
753 }
754 
755 static void virtio_blk_handle_zone_report(VirtIOBlockReq *req,
756                                          struct iovec *in_iov,
757                                          unsigned in_num)
758 {
759     VirtIOBlock *s = req->dev;
760     VirtIODevice *vdev = VIRTIO_DEVICE(s);
761     unsigned int nr_zones;
762     ZoneCmdData *data;
763     int64_t zone_size, offset;
764     uint8_t err_status;
765 
766     if (req->in_len < sizeof(struct virtio_blk_inhdr) +
767             sizeof(struct virtio_blk_zone_report) +
768             sizeof(struct virtio_blk_zone_descriptor)) {
769         virtio_error(vdev, "in buffer too small for zone report");
770         return;
771     }
772 
773     /* start byte offset of the zone report */
774     offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
775     if (!check_zoned_request(s, offset, 0, false, &err_status)) {
776         goto out;
777     }
778     nr_zones = (req->in_len - sizeof(struct virtio_blk_inhdr) -
779                 sizeof(struct virtio_blk_zone_report)) /
780                sizeof(struct virtio_blk_zone_descriptor);
781     trace_virtio_blk_handle_zone_report(vdev, req,
782                                         offset >> BDRV_SECTOR_BITS, nr_zones);
783 
784     zone_size = sizeof(BlockZoneDescriptor) * nr_zones;
785     data = g_malloc(sizeof(ZoneCmdData));
786     data->req = req;
787     data->in_iov = in_iov;
788     data->in_num = in_num;
789     data->zone_report_data.nr_zones = nr_zones;
790     data->zone_report_data.zones = g_malloc(zone_size),
791 
792     blk_aio_zone_report(s->blk, offset, &data->zone_report_data.nr_zones,
793                         data->zone_report_data.zones,
794                         virtio_blk_zone_report_complete, data);
795     return;
796 out:
797     virtio_blk_req_complete(req, err_status);
798     virtio_blk_free_request(req);
799 }
800 
801 static void virtio_blk_zone_mgmt_complete(void *opaque, int ret)
802 {
803     VirtIOBlockReq *req = opaque;
804     VirtIOBlock *s = req->dev;
805     VirtIODevice *vdev = VIRTIO_DEVICE(s);
806     int8_t err_status = VIRTIO_BLK_S_OK;
807     trace_virtio_blk_zone_mgmt_complete(vdev, req,ret);
808 
809     if (ret) {
810         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
811     }
812 
813     virtio_blk_req_complete(req, err_status);
814     virtio_blk_free_request(req);
815 }
816 
817 static int virtio_blk_handle_zone_mgmt(VirtIOBlockReq *req, BlockZoneOp op)
818 {
819     VirtIOBlock *s = req->dev;
820     VirtIODevice *vdev = VIRTIO_DEVICE(s);
821     BlockDriverState *bs = blk_bs(s->blk);
822     int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
823     uint64_t len;
824     uint64_t capacity = bs->total_sectors << BDRV_SECTOR_BITS;
825     uint8_t err_status = VIRTIO_BLK_S_OK;
826 
827     uint32_t type = virtio_ldl_p(vdev, &req->out.type);
828     if (type == VIRTIO_BLK_T_ZONE_RESET_ALL) {
829         /* Entire drive capacity */
830         offset = 0;
831         len = capacity;
832         trace_virtio_blk_handle_zone_reset_all(vdev, req, 0,
833                                                bs->total_sectors);
834     } else {
835         if (bs->bl.zone_size > capacity - offset) {
836             /* The zoned device allows the last smaller zone. */
837             len = capacity - bs->bl.zone_size * (bs->bl.nr_zones - 1);
838         } else {
839             len = bs->bl.zone_size;
840         }
841         trace_virtio_blk_handle_zone_mgmt(vdev, req, op,
842                                           offset >> BDRV_SECTOR_BITS,
843                                           len >> BDRV_SECTOR_BITS);
844     }
845 
846     if (!check_zoned_request(s, offset, len, false, &err_status)) {
847         goto out;
848     }
849 
850     blk_aio_zone_mgmt(s->blk, op, offset, len,
851                       virtio_blk_zone_mgmt_complete, req);
852 
853     return 0;
854 out:
855     virtio_blk_req_complete(req, err_status);
856     virtio_blk_free_request(req);
857     return err_status;
858 }
859 
860 static void virtio_blk_zone_append_complete(void *opaque, int ret)
861 {
862     ZoneCmdData *data = opaque;
863     VirtIOBlockReq *req = data->req;
864     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
865     int64_t append_sector, n;
866     uint8_t err_status = VIRTIO_BLK_S_OK;
867 
868     if (ret) {
869         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
870         goto out;
871     }
872 
873     virtio_stq_p(vdev, &append_sector,
874                  data->zone_append_data.offset >> BDRV_SECTOR_BITS);
875     n = iov_from_buf(data->in_iov, data->in_num, 0, &append_sector,
876                      sizeof(append_sector));
877     if (n != sizeof(append_sector)) {
878         virtio_error(vdev, "Driver provided input buffer less than size of "
879                            "append_sector");
880         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
881         goto out;
882     }
883     trace_virtio_blk_zone_append_complete(vdev, req, append_sector, ret);
884 
885 out:
886     virtio_blk_req_complete(req, err_status);
887     virtio_blk_free_request(req);
888     g_free(data);
889 }
890 
891 static int virtio_blk_handle_zone_append(VirtIOBlockReq *req,
892                                          struct iovec *out_iov,
893                                          struct iovec *in_iov,
894                                          uint64_t out_num,
895                                          unsigned in_num) {
896     VirtIOBlock *s = req->dev;
897     VirtIODevice *vdev = VIRTIO_DEVICE(s);
898     uint8_t err_status = VIRTIO_BLK_S_OK;
899 
900     int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
901     int64_t len = iov_size(out_iov, out_num);
902 
903     trace_virtio_blk_handle_zone_append(vdev, req, offset >> BDRV_SECTOR_BITS);
904     if (!check_zoned_request(s, offset, len, true, &err_status)) {
905         goto out;
906     }
907 
908     ZoneCmdData *data = g_malloc(sizeof(ZoneCmdData));
909     data->req = req;
910     data->in_iov = in_iov;
911     data->in_num = in_num;
912     data->zone_append_data.offset = offset;
913     qemu_iovec_init_external(&req->qiov, out_iov, out_num);
914 
915     block_acct_start(blk_get_stats(s->blk), &req->acct, len,
916                      BLOCK_ACCT_ZONE_APPEND);
917 
918     blk_aio_zone_append(s->blk, &data->zone_append_data.offset, &req->qiov, 0,
919                         virtio_blk_zone_append_complete, data);
920     return 0;
921 
922 out:
923     virtio_blk_req_complete(req, err_status);
924     virtio_blk_free_request(req);
925     return err_status;
926 }
927 
928 static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
929 {
930     uint32_t type;
931     struct iovec *in_iov = req->elem.in_sg;
932     struct iovec *out_iov = req->elem.out_sg;
933     unsigned in_num = req->elem.in_num;
934     unsigned out_num = req->elem.out_num;
935     VirtIOBlock *s = req->dev;
936     VirtIODevice *vdev = VIRTIO_DEVICE(s);
937 
938     if (req->elem.out_num < 1 || req->elem.in_num < 1) {
939         virtio_error(vdev, "virtio-blk missing headers");
940         return -1;
941     }
942 
943     if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
944                             sizeof(req->out)) != sizeof(req->out))) {
945         virtio_error(vdev, "virtio-blk request outhdr too short");
946         return -1;
947     }
948 
949     iov_discard_front_undoable(&out_iov, &out_num, sizeof(req->out),
950                                &req->outhdr_undo);
951 
952     if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
953         virtio_error(vdev, "virtio-blk request inhdr too short");
954         iov_discard_undo(&req->outhdr_undo);
955         return -1;
956     }
957 
958     /* We always touch the last byte, so just see how big in_iov is.  */
959     req->in_len = iov_size(in_iov, in_num);
960     req->in = (void *)in_iov[in_num - 1].iov_base
961               + in_iov[in_num - 1].iov_len
962               - sizeof(struct virtio_blk_inhdr);
963     iov_discard_back_undoable(in_iov, &in_num, sizeof(struct virtio_blk_inhdr),
964                               &req->inhdr_undo);
965 
966     type = virtio_ldl_p(vdev, &req->out.type);
967 
968     /* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER
969      * is an optional flag. Although a guest should not send this flag if
970      * not negotiated we ignored it in the past. So keep ignoring it. */
971     switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) {
972     case VIRTIO_BLK_T_IN:
973     {
974         bool is_write = type & VIRTIO_BLK_T_OUT;
975         req->sector_num = virtio_ldq_p(vdev, &req->out.sector);
976 
977         if (is_write) {
978             qemu_iovec_init_external(&req->qiov, out_iov, out_num);
979             trace_virtio_blk_handle_write(vdev, req, req->sector_num,
980                                           req->qiov.size / BDRV_SECTOR_SIZE);
981         } else {
982             qemu_iovec_init_external(&req->qiov, in_iov, in_num);
983             trace_virtio_blk_handle_read(vdev, req, req->sector_num,
984                                          req->qiov.size / BDRV_SECTOR_SIZE);
985         }
986 
987         if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) {
988             virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
989             block_acct_invalid(blk_get_stats(s->blk),
990                                is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
991             virtio_blk_free_request(req);
992             return 0;
993         }
994 
995         block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size,
996                          is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
997 
998         /* merge would exceed maximum number of requests or IO direction
999          * changes */
1000         if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS ||
1001                                   is_write != mrb->is_write ||
1002                                   !s->conf.request_merging)) {
1003             virtio_blk_submit_multireq(s, mrb);
1004         }
1005 
1006         assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS);
1007         mrb->reqs[mrb->num_reqs++] = req;
1008         mrb->is_write = is_write;
1009         break;
1010     }
1011     case VIRTIO_BLK_T_FLUSH:
1012         virtio_blk_handle_flush(req, mrb);
1013         break;
1014     case VIRTIO_BLK_T_ZONE_REPORT:
1015         virtio_blk_handle_zone_report(req, in_iov, in_num);
1016         break;
1017     case VIRTIO_BLK_T_ZONE_OPEN:
1018         virtio_blk_handle_zone_mgmt(req, BLK_ZO_OPEN);
1019         break;
1020     case VIRTIO_BLK_T_ZONE_CLOSE:
1021         virtio_blk_handle_zone_mgmt(req, BLK_ZO_CLOSE);
1022         break;
1023     case VIRTIO_BLK_T_ZONE_FINISH:
1024         virtio_blk_handle_zone_mgmt(req, BLK_ZO_FINISH);
1025         break;
1026     case VIRTIO_BLK_T_ZONE_RESET:
1027         virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
1028         break;
1029     case VIRTIO_BLK_T_ZONE_RESET_ALL:
1030         virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
1031         break;
1032     case VIRTIO_BLK_T_SCSI_CMD:
1033         virtio_blk_handle_scsi(req);
1034         break;
1035     case VIRTIO_BLK_T_GET_ID:
1036     {
1037         /*
1038          * NB: per existing s/n string convention the string is
1039          * terminated by '\0' only when shorter than buffer.
1040          */
1041         const char *serial = s->conf.serial ? s->conf.serial : "";
1042         size_t size = MIN(strlen(serial) + 1,
1043                           MIN(iov_size(in_iov, in_num),
1044                               VIRTIO_BLK_ID_BYTES));
1045         iov_from_buf(in_iov, in_num, 0, serial, size);
1046         virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
1047         virtio_blk_free_request(req);
1048         break;
1049     }
1050     case VIRTIO_BLK_T_ZONE_APPEND & ~VIRTIO_BLK_T_OUT:
1051         /*
1052          * Passing out_iov/out_num and in_iov/in_num is not safe
1053          * to access req->elem.out_sg directly because it may be
1054          * modified by virtio_blk_handle_request().
1055          */
1056         virtio_blk_handle_zone_append(req, out_iov, in_iov, out_num, in_num);
1057         break;
1058     /*
1059      * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with
1060      * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement,
1061      * so we must mask it for these requests, then we will check if it is set.
1062      */
1063     case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT:
1064     case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT:
1065     {
1066         struct virtio_blk_discard_write_zeroes dwz_hdr;
1067         size_t out_len = iov_size(out_iov, out_num);
1068         bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) ==
1069                                VIRTIO_BLK_T_WRITE_ZEROES;
1070         uint8_t err_status;
1071 
1072         /*
1073          * Unsupported if VIRTIO_BLK_T_OUT is not set or the request contains
1074          * more than one segment.
1075          */
1076         if (unlikely(!(type & VIRTIO_BLK_T_OUT) ||
1077                      out_len > sizeof(dwz_hdr))) {
1078             virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
1079             virtio_blk_free_request(req);
1080             return 0;
1081         }
1082 
1083         if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr,
1084                                 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) {
1085             iov_discard_undo(&req->inhdr_undo);
1086             iov_discard_undo(&req->outhdr_undo);
1087             virtio_error(vdev, "virtio-blk discard/write_zeroes header"
1088                          " too short");
1089             return -1;
1090         }
1091 
1092         err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr,
1093                                                             is_write_zeroes);
1094         if (err_status != VIRTIO_BLK_S_OK) {
1095             virtio_blk_req_complete(req, err_status);
1096             virtio_blk_free_request(req);
1097         }
1098 
1099         break;
1100     }
1101     default:
1102         virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
1103         virtio_blk_free_request(req);
1104     }
1105     return 0;
1106 }
1107 
1108 void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq)
1109 {
1110     VirtIOBlockReq *req;
1111     MultiReqBuffer mrb = {};
1112     bool suppress_notifications = virtio_queue_get_notification(vq);
1113 
1114     defer_call_begin();
1115 
1116     do {
1117         if (suppress_notifications) {
1118             virtio_queue_set_notification(vq, 0);
1119         }
1120 
1121         while ((req = virtio_blk_get_request(s, vq))) {
1122             if (virtio_blk_handle_request(req, &mrb)) {
1123                 virtqueue_detach_element(req->vq, &req->elem, 0);
1124                 virtio_blk_free_request(req);
1125                 break;
1126             }
1127         }
1128 
1129         if (suppress_notifications) {
1130             virtio_queue_set_notification(vq, 1);
1131         }
1132     } while (!virtio_queue_empty(vq));
1133 
1134     if (mrb.num_reqs) {
1135         virtio_blk_submit_multireq(s, &mrb);
1136     }
1137 
1138     defer_call_end();
1139 }
1140 
1141 static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
1142 {
1143     VirtIOBlock *s = (VirtIOBlock *)vdev;
1144 
1145     if (s->dataplane && !s->dataplane_started) {
1146         /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
1147          * dataplane here instead of waiting for .set_status().
1148          */
1149         virtio_device_start_ioeventfd(vdev);
1150         if (!s->dataplane_disabled) {
1151             return;
1152         }
1153     }
1154 
1155     virtio_blk_handle_vq(s, vq);
1156 }
1157 
1158 static void virtio_blk_dma_restart_bh(void *opaque)
1159 {
1160     VirtIOBlock *s = opaque;
1161 
1162     VirtIOBlockReq *req;
1163     MultiReqBuffer mrb = {};
1164 
1165     WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1166         req = s->rq;
1167         s->rq = NULL;
1168     }
1169 
1170     while (req) {
1171         VirtIOBlockReq *next = req->next;
1172         if (virtio_blk_handle_request(req, &mrb)) {
1173             /* Device is now broken and won't do any processing until it gets
1174              * reset. Already queued requests will be lost: let's purge them.
1175              */
1176             while (req) {
1177                 next = req->next;
1178                 virtqueue_detach_element(req->vq, &req->elem, 0);
1179                 virtio_blk_free_request(req);
1180                 req = next;
1181             }
1182             break;
1183         }
1184         req = next;
1185     }
1186 
1187     if (mrb.num_reqs) {
1188         virtio_blk_submit_multireq(s, &mrb);
1189     }
1190 
1191     /* Paired with inc in virtio_blk_dma_restart_cb() */
1192     blk_dec_in_flight(s->conf.conf.blk);
1193 }
1194 
1195 static void virtio_blk_dma_restart_cb(void *opaque, bool running,
1196                                       RunState state)
1197 {
1198     VirtIOBlock *s = opaque;
1199 
1200     if (!running) {
1201         return;
1202     }
1203 
1204     /* Paired with dec in virtio_blk_dma_restart_bh() */
1205     blk_inc_in_flight(s->conf.conf.blk);
1206 
1207     aio_bh_schedule_oneshot(blk_get_aio_context(s->conf.conf.blk),
1208             virtio_blk_dma_restart_bh, s);
1209 }
1210 
1211 static void virtio_blk_reset(VirtIODevice *vdev)
1212 {
1213     VirtIOBlock *s = VIRTIO_BLK(vdev);
1214     VirtIOBlockReq *req;
1215 
1216     /* Dataplane has stopped... */
1217     assert(!s->dataplane_started);
1218 
1219     /* ...but requests may still be in flight. */
1220     blk_drain(s->blk);
1221 
1222     /* We drop queued requests after blk_drain() because blk_drain() itself can
1223      * produce them. */
1224     WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1225         while (s->rq) {
1226             req = s->rq;
1227             s->rq = req->next;
1228 
1229             /* No other threads can access req->vq here */
1230             virtqueue_detach_element(req->vq, &req->elem, 0);
1231 
1232             virtio_blk_free_request(req);
1233         }
1234     }
1235 
1236     blk_set_enable_write_cache(s->blk, s->original_wce);
1237 }
1238 
1239 /* coalesce internal state, copy to pci i/o region 0
1240  */
1241 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
1242 {
1243     VirtIOBlock *s = VIRTIO_BLK(vdev);
1244     BlockConf *conf = &s->conf.conf;
1245     BlockDriverState *bs = blk_bs(s->blk);
1246     struct virtio_blk_config blkcfg;
1247     uint64_t capacity;
1248     int64_t length;
1249     int blk_size = conf->logical_block_size;
1250 
1251     blk_get_geometry(s->blk, &capacity);
1252     memset(&blkcfg, 0, sizeof(blkcfg));
1253     virtio_stq_p(vdev, &blkcfg.capacity, capacity);
1254     virtio_stl_p(vdev, &blkcfg.seg_max,
1255                  s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2);
1256     virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls);
1257     virtio_stl_p(vdev, &blkcfg.blk_size, blk_size);
1258     virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size);
1259     virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
1260     blkcfg.geometry.heads = conf->heads;
1261     /*
1262      * We must ensure that the block device capacity is a multiple of
1263      * the logical block size. If that is not the case, let's use
1264      * sector_mask to adopt the geometry to have a correct picture.
1265      * For those devices where the capacity is ok for the given geometry
1266      * we don't touch the sector value of the geometry, since some devices
1267      * (like s390 dasd) need a specific value. Here the capacity is already
1268      * cyls*heads*secs*blk_size and the sector value is not block size
1269      * divided by 512 - instead it is the amount of blk_size blocks
1270      * per track (cylinder).
1271      */
1272     length = blk_getlength(s->blk);
1273     if (length > 0 && length / conf->heads / conf->secs % blk_size) {
1274         blkcfg.geometry.sectors = conf->secs & ~s->sector_mask;
1275     } else {
1276         blkcfg.geometry.sectors = conf->secs;
1277     }
1278     blkcfg.size_max = 0;
1279     blkcfg.physical_block_exp = get_physical_block_exp(conf);
1280     blkcfg.alignment_offset = 0;
1281     blkcfg.wce = blk_enable_write_cache(s->blk);
1282     virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues);
1283     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) {
1284         uint32_t discard_granularity = conf->discard_granularity;
1285         if (discard_granularity == -1 || !s->conf.report_discard_granularity) {
1286             discard_granularity = blk_size;
1287         }
1288         virtio_stl_p(vdev, &blkcfg.max_discard_sectors,
1289                      s->conf.max_discard_sectors);
1290         virtio_stl_p(vdev, &blkcfg.discard_sector_alignment,
1291                      discard_granularity >> BDRV_SECTOR_BITS);
1292         /*
1293          * We support only one segment per request since multiple segments
1294          * are not widely used and there are no userspace APIs that allow
1295          * applications to submit multiple segments in a single call.
1296          */
1297         virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1);
1298     }
1299     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) {
1300         virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors,
1301                      s->conf.max_write_zeroes_sectors);
1302         blkcfg.write_zeroes_may_unmap = 1;
1303         virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1);
1304     }
1305     if (bs->bl.zoned != BLK_Z_NONE) {
1306         switch (bs->bl.zoned) {
1307         case BLK_Z_HM:
1308             blkcfg.zoned.model = VIRTIO_BLK_Z_HM;
1309             break;
1310         case BLK_Z_HA:
1311             blkcfg.zoned.model = VIRTIO_BLK_Z_HA;
1312             break;
1313         default:
1314             g_assert_not_reached();
1315         }
1316 
1317         virtio_stl_p(vdev, &blkcfg.zoned.zone_sectors,
1318                      bs->bl.zone_size / 512);
1319         virtio_stl_p(vdev, &blkcfg.zoned.max_active_zones,
1320                      bs->bl.max_active_zones);
1321         virtio_stl_p(vdev, &blkcfg.zoned.max_open_zones,
1322                      bs->bl.max_open_zones);
1323         virtio_stl_p(vdev, &blkcfg.zoned.write_granularity, blk_size);
1324         virtio_stl_p(vdev, &blkcfg.zoned.max_append_sectors,
1325                      bs->bl.max_append_sectors);
1326     } else {
1327         blkcfg.zoned.model = VIRTIO_BLK_Z_NONE;
1328     }
1329     memcpy(config, &blkcfg, s->config_size);
1330 }
1331 
1332 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
1333 {
1334     VirtIOBlock *s = VIRTIO_BLK(vdev);
1335     struct virtio_blk_config blkcfg;
1336 
1337     memcpy(&blkcfg, config, s->config_size);
1338 
1339     blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
1340 }
1341 
1342 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features,
1343                                         Error **errp)
1344 {
1345     VirtIOBlock *s = VIRTIO_BLK(vdev);
1346 
1347     /* Firstly sync all virtio-blk possible supported features */
1348     features |= s->host_features;
1349 
1350     virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX);
1351     virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY);
1352     virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY);
1353     virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE);
1354     if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) {
1355         if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) {
1356             error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0");
1357             return 0;
1358         }
1359     } else {
1360         virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT);
1361         virtio_add_feature(&features, VIRTIO_BLK_F_SCSI);
1362     }
1363 
1364     if (blk_enable_write_cache(s->blk) ||
1365         (s->conf.x_enable_wce_if_config_wce &&
1366          virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) {
1367         virtio_add_feature(&features, VIRTIO_BLK_F_WCE);
1368     }
1369     if (!blk_is_writable(s->blk)) {
1370         virtio_add_feature(&features, VIRTIO_BLK_F_RO);
1371     }
1372     if (s->conf.num_queues > 1) {
1373         virtio_add_feature(&features, VIRTIO_BLK_F_MQ);
1374     }
1375 
1376     return features;
1377 }
1378 
1379 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
1380 {
1381     VirtIOBlock *s = VIRTIO_BLK(vdev);
1382 
1383     if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) {
1384         assert(!s->dataplane_started);
1385     }
1386 
1387     if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
1388         return;
1389     }
1390 
1391     /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send
1392      * cache flushes.  Thus, the "auto writethrough" behavior is never
1393      * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature.
1394      * Leaving it enabled would break the following sequence:
1395      *
1396      *     Guest started with "-drive cache=writethrough"
1397      *     Guest sets status to 0
1398      *     Guest sets DRIVER bit in status field
1399      *     Guest reads host features (WCE=0, CONFIG_WCE=1)
1400      *     Guest writes guest features (WCE=0, CONFIG_WCE=1)
1401      *     Guest writes 1 to the WCE configuration field (writeback mode)
1402      *     Guest sets DRIVER_OK bit in status field
1403      *
1404      * s->blk would erroneously be placed in writethrough mode.
1405      */
1406     if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) {
1407         blk_set_enable_write_cache(s->blk,
1408                                    virtio_vdev_has_feature(vdev,
1409                                                            VIRTIO_BLK_F_WCE));
1410     }
1411 }
1412 
1413 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f)
1414 {
1415     VirtIOBlock *s = VIRTIO_BLK(vdev);
1416 
1417     WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1418         VirtIOBlockReq *req = s->rq;
1419 
1420         while (req) {
1421             qemu_put_sbyte(f, 1);
1422 
1423             if (s->conf.num_queues > 1) {
1424                 qemu_put_be32(f, virtio_get_queue_index(req->vq));
1425             }
1426 
1427             qemu_put_virtqueue_element(vdev, f, &req->elem);
1428             req = req->next;
1429         }
1430     }
1431 
1432     qemu_put_sbyte(f, 0);
1433 }
1434 
1435 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
1436                                   int version_id)
1437 {
1438     VirtIOBlock *s = VIRTIO_BLK(vdev);
1439 
1440     while (qemu_get_sbyte(f)) {
1441         unsigned nvqs = s->conf.num_queues;
1442         unsigned vq_idx = 0;
1443         VirtIOBlockReq *req;
1444 
1445         if (nvqs > 1) {
1446             vq_idx = qemu_get_be32(f);
1447 
1448             if (vq_idx >= nvqs) {
1449                 error_report("Invalid virtqueue index in request list: %#x",
1450                              vq_idx);
1451                 return -EINVAL;
1452             }
1453         }
1454 
1455         req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq));
1456         virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req);
1457 
1458         WITH_QEMU_LOCK_GUARD(&s->rq_lock) {
1459             req->next = s->rq;
1460             s->rq = req;
1461         }
1462     }
1463 
1464     return 0;
1465 }
1466 
1467 static bool
1468 validate_iothread_vq_mapping_list(IOThreadVirtQueueMappingList *list,
1469         uint16_t num_queues, Error **errp)
1470 {
1471     g_autofree unsigned long *vqs = bitmap_new(num_queues);
1472     g_autoptr(GHashTable) iothreads =
1473         g_hash_table_new(g_str_hash, g_str_equal);
1474 
1475     for (IOThreadVirtQueueMappingList *node = list; node; node = node->next) {
1476         const char *name = node->value->iothread;
1477         uint16List *vq;
1478 
1479         if (!iothread_by_id(name)) {
1480             error_setg(errp, "IOThread \"%s\" object does not exist", name);
1481             return false;
1482         }
1483 
1484         if (!g_hash_table_add(iothreads, (gpointer)name)) {
1485             error_setg(errp,
1486                     "duplicate IOThread name \"%s\" in iothread-vq-mapping",
1487                     name);
1488             return false;
1489         }
1490 
1491         if (node != list) {
1492             if (!!node->value->vqs != !!list->value->vqs) {
1493                 error_setg(errp, "either all items in iothread-vq-mapping "
1494                                  "must have vqs or none of them must have it");
1495                 return false;
1496             }
1497         }
1498 
1499         for (vq = node->value->vqs; vq; vq = vq->next) {
1500             if (vq->value >= num_queues) {
1501                 error_setg(errp, "vq index %u for IOThread \"%s\" must be "
1502                         "less than num_queues %u in iothread-vq-mapping",
1503                         vq->value, name, num_queues);
1504                 return false;
1505             }
1506 
1507             if (test_and_set_bit(vq->value, vqs)) {
1508                 error_setg(errp, "cannot assign vq %u to IOThread \"%s\" "
1509                         "because it is already assigned", vq->value, name);
1510                 return false;
1511             }
1512         }
1513     }
1514 
1515     if (list->value->vqs) {
1516         for (uint16_t i = 0; i < num_queues; i++) {
1517             if (!test_bit(i, vqs)) {
1518                 error_setg(errp,
1519                         "missing vq %u IOThread assignment in iothread-vq-mapping",
1520                         i);
1521                 return false;
1522             }
1523         }
1524     }
1525 
1526     return true;
1527 }
1528 
1529 static void virtio_resize_cb(void *opaque)
1530 {
1531     VirtIODevice *vdev = opaque;
1532 
1533     assert(qemu_get_current_aio_context() == qemu_get_aio_context());
1534     virtio_notify_config(vdev);
1535 }
1536 
1537 static void virtio_blk_resize(void *opaque)
1538 {
1539     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
1540 
1541     /*
1542      * virtio_notify_config() needs to acquire the global mutex,
1543      * so it can't be called from an iothread. Instead, schedule
1544      * it to be run in the main context BH.
1545      */
1546     aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev);
1547 }
1548 
1549 /* Suspend virtqueue ioeventfd processing during drain */
1550 static void virtio_blk_drained_begin(void *opaque)
1551 {
1552     VirtIOBlock *s = opaque;
1553 
1554     if (!s->dataplane || !s->dataplane_started) {
1555         return;
1556     }
1557 
1558     virtio_blk_data_plane_detach(s->dataplane);
1559 }
1560 
1561 /* Resume virtqueue ioeventfd processing after drain */
1562 static void virtio_blk_drained_end(void *opaque)
1563 {
1564     VirtIOBlock *s = opaque;
1565 
1566     if (!s->dataplane || !s->dataplane_started) {
1567         return;
1568     }
1569 
1570     virtio_blk_data_plane_attach(s->dataplane);
1571 }
1572 
1573 static const BlockDevOps virtio_block_ops = {
1574     .resize_cb     = virtio_blk_resize,
1575     .drained_begin = virtio_blk_drained_begin,
1576     .drained_end   = virtio_blk_drained_end,
1577 };
1578 
1579 static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
1580 {
1581     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1582     VirtIOBlock *s = VIRTIO_BLK(dev);
1583     VirtIOBlkConf *conf = &s->conf;
1584     Error *err = NULL;
1585     unsigned i;
1586 
1587     if (!conf->conf.blk) {
1588         error_setg(errp, "drive property not set");
1589         return;
1590     }
1591     if (!blk_is_inserted(conf->conf.blk)) {
1592         error_setg(errp, "Device needs media, but drive is empty");
1593         return;
1594     }
1595     if (conf->num_queues == VIRTIO_BLK_AUTO_NUM_QUEUES) {
1596         conf->num_queues = 1;
1597     }
1598     if (!conf->num_queues) {
1599         error_setg(errp, "num-queues property must be larger than 0");
1600         return;
1601     }
1602     if (conf->queue_size <= 2) {
1603         error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1604                    "must be > 2", conf->queue_size);
1605         return;
1606     }
1607     if (!is_power_of_2(conf->queue_size) ||
1608         conf->queue_size > VIRTQUEUE_MAX_SIZE) {
1609         error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1610                    "must be a power of 2 (max %d)",
1611                    conf->queue_size, VIRTQUEUE_MAX_SIZE);
1612         return;
1613     }
1614 
1615     if (!blkconf_apply_backend_options(&conf->conf,
1616                                        !blk_supports_write_perm(conf->conf.blk),
1617                                        true, errp)) {
1618         return;
1619     }
1620     s->original_wce = blk_enable_write_cache(conf->conf.blk);
1621     if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) {
1622         return;
1623     }
1624 
1625     if (!blkconf_blocksizes(&conf->conf, errp)) {
1626         return;
1627     }
1628 
1629     BlockDriverState *bs = blk_bs(conf->conf.blk);
1630     if (bs->bl.zoned != BLK_Z_NONE) {
1631         virtio_add_feature(&s->host_features, VIRTIO_BLK_F_ZONED);
1632         if (bs->bl.zoned == BLK_Z_HM) {
1633             virtio_clear_feature(&s->host_features, VIRTIO_BLK_F_DISCARD);
1634         }
1635     }
1636 
1637     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) &&
1638         (!conf->max_discard_sectors ||
1639          conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1640         error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")"
1641                    ", must be between 1 and %d",
1642                    conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS);
1643         return;
1644     }
1645 
1646     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) &&
1647         (!conf->max_write_zeroes_sectors ||
1648          conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1649         error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32
1650                    "), must be between 1 and %d",
1651                    conf->max_write_zeroes_sectors,
1652                    (int)BDRV_REQUEST_MAX_SECTORS);
1653         return;
1654     }
1655 
1656     if (conf->iothread_vq_mapping_list) {
1657         if (conf->iothread) {
1658             error_setg(errp, "iothread and iothread-vq-mapping properties "
1659                              "cannot be set at the same time");
1660             return;
1661         }
1662 
1663         if (!validate_iothread_vq_mapping_list(conf->iothread_vq_mapping_list,
1664                                                conf->num_queues, errp)) {
1665             return;
1666         }
1667     }
1668 
1669     s->config_size = virtio_get_config_size(&virtio_blk_cfg_size_params,
1670                                             s->host_features);
1671     virtio_init(vdev, VIRTIO_ID_BLOCK, s->config_size);
1672 
1673     qemu_mutex_init(&s->rq_lock);
1674 
1675     s->blk = conf->conf.blk;
1676     s->rq = NULL;
1677     s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1;
1678 
1679     for (i = 0; i < conf->num_queues; i++) {
1680         virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output);
1681     }
1682     qemu_coroutine_inc_pool_size(conf->num_queues * conf->queue_size / 2);
1683     virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err);
1684     if (err != NULL) {
1685         error_propagate(errp, err);
1686         for (i = 0; i < conf->num_queues; i++) {
1687             virtio_del_queue(vdev, i);
1688         }
1689         virtio_cleanup(vdev);
1690         return;
1691     }
1692 
1693     /*
1694      * This must be after virtio_init() so virtio_blk_dma_restart_cb() gets
1695      * called after ->start_ioeventfd() has already set blk's AioContext.
1696      */
1697     s->change =
1698         qdev_add_vm_change_state_handler(dev, virtio_blk_dma_restart_cb, s);
1699 
1700     blk_ram_registrar_init(&s->blk_ram_registrar, s->blk);
1701     blk_set_dev_ops(s->blk, &virtio_block_ops, s);
1702 
1703     blk_iostatus_enable(s->blk);
1704 
1705     add_boot_device_lchs(dev, "/disk@0,0",
1706                          conf->conf.lcyls,
1707                          conf->conf.lheads,
1708                          conf->conf.lsecs);
1709 }
1710 
1711 static void virtio_blk_device_unrealize(DeviceState *dev)
1712 {
1713     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1714     VirtIOBlock *s = VIRTIO_BLK(dev);
1715     VirtIOBlkConf *conf = &s->conf;
1716     unsigned i;
1717 
1718     blk_drain(s->blk);
1719     del_boot_device_lchs(dev, "/disk@0,0");
1720     virtio_blk_data_plane_destroy(s->dataplane);
1721     s->dataplane = NULL;
1722     for (i = 0; i < conf->num_queues; i++) {
1723         virtio_del_queue(vdev, i);
1724     }
1725     qemu_coroutine_dec_pool_size(conf->num_queues * conf->queue_size / 2);
1726     qemu_mutex_destroy(&s->rq_lock);
1727     blk_ram_registrar_destroy(&s->blk_ram_registrar);
1728     qemu_del_vm_change_state_handler(s->change);
1729     blockdev_mark_auto_del(s->blk);
1730     virtio_cleanup(vdev);
1731 }
1732 
1733 static void virtio_blk_instance_init(Object *obj)
1734 {
1735     VirtIOBlock *s = VIRTIO_BLK(obj);
1736 
1737     device_add_bootindex_property(obj, &s->conf.conf.bootindex,
1738                                   "bootindex", "/disk@0,0",
1739                                   DEVICE(obj));
1740 }
1741 
1742 static const VMStateDescription vmstate_virtio_blk = {
1743     .name = "virtio-blk",
1744     .minimum_version_id = 2,
1745     .version_id = 2,
1746     .fields = (VMStateField[]) {
1747         VMSTATE_VIRTIO_DEVICE,
1748         VMSTATE_END_OF_LIST()
1749     },
1750 };
1751 
1752 static Property virtio_blk_properties[] = {
1753     DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf),
1754     DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf),
1755     DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf),
1756     DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial),
1757     DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features,
1758                       VIRTIO_BLK_F_CONFIG_WCE, true),
1759 #ifdef __linux__
1760     DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features,
1761                       VIRTIO_BLK_F_SCSI, false),
1762 #endif
1763     DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
1764                     true),
1765     DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues,
1766                        VIRTIO_BLK_AUTO_NUM_QUEUES),
1767     DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256),
1768     DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true),
1769     DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD,
1770                      IOThread *),
1771     DEFINE_PROP_IOTHREAD_VQ_MAPPING_LIST("iothread-vq-mapping", VirtIOBlock,
1772                                          conf.iothread_vq_mapping_list),
1773     DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features,
1774                       VIRTIO_BLK_F_DISCARD, true),
1775     DEFINE_PROP_BOOL("report-discard-granularity", VirtIOBlock,
1776                      conf.report_discard_granularity, true),
1777     DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features,
1778                       VIRTIO_BLK_F_WRITE_ZEROES, true),
1779     DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock,
1780                        conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS),
1781     DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock,
1782                        conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS),
1783     DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock,
1784                      conf.x_enable_wce_if_config_wce, true),
1785     DEFINE_PROP_END_OF_LIST(),
1786 };
1787 
1788 static void virtio_blk_class_init(ObjectClass *klass, void *data)
1789 {
1790     DeviceClass *dc = DEVICE_CLASS(klass);
1791     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
1792 
1793     device_class_set_props(dc, virtio_blk_properties);
1794     dc->vmsd = &vmstate_virtio_blk;
1795     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1796     vdc->realize = virtio_blk_device_realize;
1797     vdc->unrealize = virtio_blk_device_unrealize;
1798     vdc->get_config = virtio_blk_update_config;
1799     vdc->set_config = virtio_blk_set_config;
1800     vdc->get_features = virtio_blk_get_features;
1801     vdc->set_status = virtio_blk_set_status;
1802     vdc->reset = virtio_blk_reset;
1803     vdc->save = virtio_blk_save_device;
1804     vdc->load = virtio_blk_load_device;
1805     vdc->start_ioeventfd = virtio_blk_data_plane_start;
1806     vdc->stop_ioeventfd = virtio_blk_data_plane_stop;
1807 }
1808 
1809 static const TypeInfo virtio_blk_info = {
1810     .name = TYPE_VIRTIO_BLK,
1811     .parent = TYPE_VIRTIO_DEVICE,
1812     .instance_size = sizeof(VirtIOBlock),
1813     .instance_init = virtio_blk_instance_init,
1814     .class_init = virtio_blk_class_init,
1815 };
1816 
1817 static void virtio_register_types(void)
1818 {
1819     type_register_static(&virtio_blk_info);
1820 }
1821 
1822 type_init(virtio_register_types)
1823