xref: /openbmc/qemu/hw/block/virtio-blk.c (revision d0cda6f4)
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         req->next = s->rq;
86         s->rq = req;
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         virtio_blk_free_request(req);
93     }
94 
95     blk_error_action(s->blk, action, is_read, error);
96     return action != BLOCK_ERROR_ACTION_IGNORE;
97 }
98 
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     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
106     while (next) {
107         VirtIOBlockReq *req = next;
108         next = req->mr_next;
109         trace_virtio_blk_rw_complete(vdev, req, ret);
110 
111         if (req->qiov.nalloc != -1) {
112             /* If nalloc is != -1 req->qiov is a local copy of the original
113              * external iovec. It was allocated in submit_requests to be
114              * able to merge requests. */
115             qemu_iovec_destroy(&req->qiov);
116         }
117 
118         if (ret) {
119             int p = virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type);
120             bool is_read = !(p & VIRTIO_BLK_T_OUT);
121             /* Note that memory may be dirtied on read failure.  If the
122              * virtio request is not completed here, as is the case for
123              * BLOCK_ERROR_ACTION_STOP, the memory may not be copied
124              * correctly during live migration.  While this is ugly,
125              * it is acceptable because the device is free to write to
126              * the memory until the request is completed (which will
127              * happen on the other side of the migration).
128              */
129             if (virtio_blk_handle_rw_error(req, -ret, is_read, true)) {
130                 continue;
131             }
132         }
133 
134         virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
135         block_acct_done(blk_get_stats(s->blk), &req->acct);
136         virtio_blk_free_request(req);
137     }
138     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
139 }
140 
141 static void virtio_blk_flush_complete(void *opaque, int ret)
142 {
143     VirtIOBlockReq *req = opaque;
144     VirtIOBlock *s = req->dev;
145 
146     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
147     if (ret) {
148         if (virtio_blk_handle_rw_error(req, -ret, 0, true)) {
149             goto out;
150         }
151     }
152 
153     virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
154     block_acct_done(blk_get_stats(s->blk), &req->acct);
155     virtio_blk_free_request(req);
156 
157 out:
158     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
159 }
160 
161 static void virtio_blk_discard_write_zeroes_complete(void *opaque, int ret)
162 {
163     VirtIOBlockReq *req = opaque;
164     VirtIOBlock *s = req->dev;
165     bool is_write_zeroes = (virtio_ldl_p(VIRTIO_DEVICE(s), &req->out.type) &
166                             ~VIRTIO_BLK_T_BARRIER) == VIRTIO_BLK_T_WRITE_ZEROES;
167 
168     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
169     if (ret) {
170         if (virtio_blk_handle_rw_error(req, -ret, false, is_write_zeroes)) {
171             goto out;
172         }
173     }
174 
175     virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
176     if (is_write_zeroes) {
177         block_acct_done(blk_get_stats(s->blk), &req->acct);
178     }
179     virtio_blk_free_request(req);
180 
181 out:
182     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
183 }
184 
185 #ifdef __linux__
186 
187 typedef struct {
188     VirtIOBlockReq *req;
189     struct sg_io_hdr hdr;
190 } VirtIOBlockIoctlReq;
191 
192 static void virtio_blk_ioctl_complete(void *opaque, int status)
193 {
194     VirtIOBlockIoctlReq *ioctl_req = opaque;
195     VirtIOBlockReq *req = ioctl_req->req;
196     VirtIOBlock *s = req->dev;
197     VirtIODevice *vdev = VIRTIO_DEVICE(s);
198     struct virtio_scsi_inhdr *scsi;
199     struct sg_io_hdr *hdr;
200 
201     scsi = (void *)req->elem.in_sg[req->elem.in_num - 2].iov_base;
202 
203     if (status) {
204         status = VIRTIO_BLK_S_UNSUPP;
205         virtio_stl_p(vdev, &scsi->errors, 255);
206         goto out;
207     }
208 
209     hdr = &ioctl_req->hdr;
210     /*
211      * From SCSI-Generic-HOWTO: "Some lower level drivers (e.g. ide-scsi)
212      * clear the masked_status field [hence status gets cleared too, see
213      * block/scsi_ioctl.c] even when a CHECK_CONDITION or COMMAND_TERMINATED
214      * status has occurred.  However they do set DRIVER_SENSE in driver_status
215      * field. Also a (sb_len_wr > 0) indicates there is a sense buffer.
216      */
217     if (hdr->status == 0 && hdr->sb_len_wr > 0) {
218         hdr->status = CHECK_CONDITION;
219     }
220 
221     virtio_stl_p(vdev, &scsi->errors,
222                  hdr->status | (hdr->msg_status << 8) |
223                  (hdr->host_status << 16) | (hdr->driver_status << 24));
224     virtio_stl_p(vdev, &scsi->residual, hdr->resid);
225     virtio_stl_p(vdev, &scsi->sense_len, hdr->sb_len_wr);
226     virtio_stl_p(vdev, &scsi->data_len, hdr->dxfer_len);
227 
228 out:
229     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
230     virtio_blk_req_complete(req, status);
231     virtio_blk_free_request(req);
232     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
233     g_free(ioctl_req);
234 }
235 
236 #endif
237 
238 static VirtIOBlockReq *virtio_blk_get_request(VirtIOBlock *s, VirtQueue *vq)
239 {
240     VirtIOBlockReq *req = virtqueue_pop(vq, sizeof(VirtIOBlockReq));
241 
242     if (req) {
243         virtio_blk_init_request(s, vq, req);
244     }
245     return req;
246 }
247 
248 static int virtio_blk_handle_scsi_req(VirtIOBlockReq *req)
249 {
250     int status = VIRTIO_BLK_S_OK;
251     struct virtio_scsi_inhdr *scsi = NULL;
252     VirtIOBlock *blk = req->dev;
253     VirtIODevice *vdev = VIRTIO_DEVICE(blk);
254     VirtQueueElement *elem = &req->elem;
255 
256 #ifdef __linux__
257     int i;
258     VirtIOBlockIoctlReq *ioctl_req;
259     BlockAIOCB *acb;
260 #endif
261 
262     /*
263      * We require at least one output segment each for the virtio_blk_outhdr
264      * and the SCSI command block.
265      *
266      * We also at least require the virtio_blk_inhdr, the virtio_scsi_inhdr
267      * and the sense buffer pointer in the input segments.
268      */
269     if (elem->out_num < 2 || elem->in_num < 3) {
270         status = VIRTIO_BLK_S_IOERR;
271         goto fail;
272     }
273 
274     /*
275      * The scsi inhdr is placed in the second-to-last input segment, just
276      * before the regular inhdr.
277      */
278     scsi = (void *)elem->in_sg[elem->in_num - 2].iov_base;
279 
280     if (!virtio_has_feature(blk->host_features, VIRTIO_BLK_F_SCSI)) {
281         status = VIRTIO_BLK_S_UNSUPP;
282         goto fail;
283     }
284 
285     /*
286      * No support for bidirection commands yet.
287      */
288     if (elem->out_num > 2 && elem->in_num > 3) {
289         status = VIRTIO_BLK_S_UNSUPP;
290         goto fail;
291     }
292 
293 #ifdef __linux__
294     ioctl_req = g_new0(VirtIOBlockIoctlReq, 1);
295     ioctl_req->req = req;
296     ioctl_req->hdr.interface_id = 'S';
297     ioctl_req->hdr.cmd_len = elem->out_sg[1].iov_len;
298     ioctl_req->hdr.cmdp = elem->out_sg[1].iov_base;
299     ioctl_req->hdr.dxfer_len = 0;
300 
301     if (elem->out_num > 2) {
302         /*
303          * If there are more than the minimally required 2 output segments
304          * there is write payload starting from the third iovec.
305          */
306         ioctl_req->hdr.dxfer_direction = SG_DXFER_TO_DEV;
307         ioctl_req->hdr.iovec_count = elem->out_num - 2;
308 
309         for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
310             ioctl_req->hdr.dxfer_len += elem->out_sg[i + 2].iov_len;
311         }
312 
313         ioctl_req->hdr.dxferp = elem->out_sg + 2;
314 
315     } else if (elem->in_num > 3) {
316         /*
317          * If we have more than 3 input segments the guest wants to actually
318          * read data.
319          */
320         ioctl_req->hdr.dxfer_direction = SG_DXFER_FROM_DEV;
321         ioctl_req->hdr.iovec_count = elem->in_num - 3;
322         for (i = 0; i < ioctl_req->hdr.iovec_count; i++) {
323             ioctl_req->hdr.dxfer_len += elem->in_sg[i].iov_len;
324         }
325 
326         ioctl_req->hdr.dxferp = elem->in_sg;
327     } else {
328         /*
329          * Some SCSI commands don't actually transfer any data.
330          */
331         ioctl_req->hdr.dxfer_direction = SG_DXFER_NONE;
332     }
333 
334     ioctl_req->hdr.sbp = elem->in_sg[elem->in_num - 3].iov_base;
335     ioctl_req->hdr.mx_sb_len = elem->in_sg[elem->in_num - 3].iov_len;
336 
337     acb = blk_aio_ioctl(blk->blk, SG_IO, &ioctl_req->hdr,
338                         virtio_blk_ioctl_complete, ioctl_req);
339     if (!acb) {
340         g_free(ioctl_req);
341         status = VIRTIO_BLK_S_UNSUPP;
342         goto fail;
343     }
344     return -EINPROGRESS;
345 #else
346     abort();
347 #endif
348 
349 fail:
350     /* Just put anything nonzero so that the ioctl fails in the guest.  */
351     if (scsi) {
352         virtio_stl_p(vdev, &scsi->errors, 255);
353     }
354     return status;
355 }
356 
357 static void virtio_blk_handle_scsi(VirtIOBlockReq *req)
358 {
359     int status;
360 
361     status = virtio_blk_handle_scsi_req(req);
362     if (status != -EINPROGRESS) {
363         virtio_blk_req_complete(req, status);
364         virtio_blk_free_request(req);
365     }
366 }
367 
368 static inline void submit_requests(VirtIOBlock *s, MultiReqBuffer *mrb,
369                                    int start, int num_reqs, int niov)
370 {
371     BlockBackend *blk = s->blk;
372     QEMUIOVector *qiov = &mrb->reqs[start]->qiov;
373     int64_t sector_num = mrb->reqs[start]->sector_num;
374     bool is_write = mrb->is_write;
375     BdrvRequestFlags flags = 0;
376 
377     if (num_reqs > 1) {
378         int i;
379         struct iovec *tmp_iov = qiov->iov;
380         int tmp_niov = qiov->niov;
381 
382         /* mrb->reqs[start]->qiov was initialized from external so we can't
383          * modify it here. We need to initialize it locally and then add the
384          * external iovecs. */
385         qemu_iovec_init(qiov, niov);
386 
387         for (i = 0; i < tmp_niov; i++) {
388             qemu_iovec_add(qiov, tmp_iov[i].iov_base, tmp_iov[i].iov_len);
389         }
390 
391         for (i = start + 1; i < start + num_reqs; i++) {
392             qemu_iovec_concat(qiov, &mrb->reqs[i]->qiov, 0,
393                               mrb->reqs[i]->qiov.size);
394             mrb->reqs[i - 1]->mr_next = mrb->reqs[i];
395         }
396 
397         trace_virtio_blk_submit_multireq(VIRTIO_DEVICE(mrb->reqs[start]->dev),
398                                          mrb, start, num_reqs,
399                                          sector_num << BDRV_SECTOR_BITS,
400                                          qiov->size, is_write);
401         block_acct_merge_done(blk_get_stats(blk),
402                               is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ,
403                               num_reqs - 1);
404     }
405 
406     if (blk_ram_registrar_ok(&s->blk_ram_registrar)) {
407         flags |= BDRV_REQ_REGISTERED_BUF;
408     }
409 
410     if (is_write) {
411         blk_aio_pwritev(blk, sector_num << BDRV_SECTOR_BITS, qiov,
412                         flags, virtio_blk_rw_complete,
413                         mrb->reqs[start]);
414     } else {
415         blk_aio_preadv(blk, sector_num << BDRV_SECTOR_BITS, qiov,
416                        flags, virtio_blk_rw_complete,
417                        mrb->reqs[start]);
418     }
419 }
420 
421 static int multireq_compare(const void *a, const void *b)
422 {
423     const VirtIOBlockReq *req1 = *(VirtIOBlockReq **)a,
424                          *req2 = *(VirtIOBlockReq **)b;
425 
426     /*
427      * Note that we can't simply subtract sector_num1 from sector_num2
428      * here as that could overflow the return value.
429      */
430     if (req1->sector_num > req2->sector_num) {
431         return 1;
432     } else if (req1->sector_num < req2->sector_num) {
433         return -1;
434     } else {
435         return 0;
436     }
437 }
438 
439 static void virtio_blk_submit_multireq(VirtIOBlock *s, MultiReqBuffer *mrb)
440 {
441     int i = 0, start = 0, num_reqs = 0, niov = 0, nb_sectors = 0;
442     uint32_t max_transfer;
443     int64_t sector_num = 0;
444 
445     if (mrb->num_reqs == 1) {
446         submit_requests(s, mrb, 0, 1, -1);
447         mrb->num_reqs = 0;
448         return;
449     }
450 
451     max_transfer = blk_get_max_transfer(mrb->reqs[0]->dev->blk);
452 
453     qsort(mrb->reqs, mrb->num_reqs, sizeof(*mrb->reqs),
454           &multireq_compare);
455 
456     for (i = 0; i < mrb->num_reqs; i++) {
457         VirtIOBlockReq *req = mrb->reqs[i];
458         if (num_reqs > 0) {
459             /*
460              * NOTE: We cannot merge the requests in below situations:
461              * 1. requests are not sequential
462              * 2. merge would exceed maximum number of IOVs
463              * 3. merge would exceed maximum transfer length of backend device
464              */
465             if (sector_num + nb_sectors != req->sector_num ||
466                 niov > blk_get_max_iov(s->blk) - req->qiov.niov ||
467                 req->qiov.size > max_transfer ||
468                 nb_sectors > (max_transfer -
469                               req->qiov.size) / BDRV_SECTOR_SIZE) {
470                 submit_requests(s, mrb, start, num_reqs, niov);
471                 num_reqs = 0;
472             }
473         }
474 
475         if (num_reqs == 0) {
476             sector_num = req->sector_num;
477             nb_sectors = niov = 0;
478             start = i;
479         }
480 
481         nb_sectors += req->qiov.size / BDRV_SECTOR_SIZE;
482         niov += req->qiov.niov;
483         num_reqs++;
484     }
485 
486     submit_requests(s, mrb, start, num_reqs, niov);
487     mrb->num_reqs = 0;
488 }
489 
490 static void virtio_blk_handle_flush(VirtIOBlockReq *req, MultiReqBuffer *mrb)
491 {
492     VirtIOBlock *s = req->dev;
493 
494     block_acct_start(blk_get_stats(s->blk), &req->acct, 0,
495                      BLOCK_ACCT_FLUSH);
496 
497     /*
498      * Make sure all outstanding writes are posted to the backing device.
499      */
500     if (mrb->is_write && mrb->num_reqs > 0) {
501         virtio_blk_submit_multireq(s, mrb);
502     }
503     blk_aio_flush(s->blk, virtio_blk_flush_complete, req);
504 }
505 
506 static bool virtio_blk_sect_range_ok(VirtIOBlock *dev,
507                                      uint64_t sector, size_t size)
508 {
509     uint64_t nb_sectors = size >> BDRV_SECTOR_BITS;
510     uint64_t total_sectors;
511 
512     if (nb_sectors > BDRV_REQUEST_MAX_SECTORS) {
513         return false;
514     }
515     if (sector & dev->sector_mask) {
516         return false;
517     }
518     if (size % dev->conf.conf.logical_block_size) {
519         return false;
520     }
521     blk_get_geometry(dev->blk, &total_sectors);
522     if (sector > total_sectors || nb_sectors > total_sectors - sector) {
523         return false;
524     }
525     return true;
526 }
527 
528 static uint8_t virtio_blk_handle_discard_write_zeroes(VirtIOBlockReq *req,
529     struct virtio_blk_discard_write_zeroes *dwz_hdr, bool is_write_zeroes)
530 {
531     VirtIOBlock *s = req->dev;
532     VirtIODevice *vdev = VIRTIO_DEVICE(s);
533     uint64_t sector;
534     uint32_t num_sectors, flags, max_sectors;
535     uint8_t err_status;
536     int bytes;
537 
538     sector = virtio_ldq_p(vdev, &dwz_hdr->sector);
539     num_sectors = virtio_ldl_p(vdev, &dwz_hdr->num_sectors);
540     flags = virtio_ldl_p(vdev, &dwz_hdr->flags);
541     max_sectors = is_write_zeroes ? s->conf.max_write_zeroes_sectors :
542                   s->conf.max_discard_sectors;
543 
544     /*
545      * max_sectors is at most BDRV_REQUEST_MAX_SECTORS, this check
546      * make us sure that "num_sectors << BDRV_SECTOR_BITS" can fit in
547      * the integer variable.
548      */
549     if (unlikely(num_sectors > max_sectors)) {
550         err_status = VIRTIO_BLK_S_IOERR;
551         goto err;
552     }
553 
554     bytes = num_sectors << BDRV_SECTOR_BITS;
555 
556     if (unlikely(!virtio_blk_sect_range_ok(s, sector, bytes))) {
557         err_status = VIRTIO_BLK_S_IOERR;
558         goto err;
559     }
560 
561     /*
562      * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for discard
563      * and write zeroes commands if any unknown flag is set.
564      */
565     if (unlikely(flags & ~VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
566         err_status = VIRTIO_BLK_S_UNSUPP;
567         goto err;
568     }
569 
570     if (is_write_zeroes) { /* VIRTIO_BLK_T_WRITE_ZEROES */
571         int blk_aio_flags = 0;
572 
573         if (flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP) {
574             blk_aio_flags |= BDRV_REQ_MAY_UNMAP;
575         }
576 
577         block_acct_start(blk_get_stats(s->blk), &req->acct, bytes,
578                          BLOCK_ACCT_WRITE);
579 
580         blk_aio_pwrite_zeroes(s->blk, sector << BDRV_SECTOR_BITS,
581                               bytes, blk_aio_flags,
582                               virtio_blk_discard_write_zeroes_complete, req);
583     } else { /* VIRTIO_BLK_T_DISCARD */
584         /*
585          * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP for
586          * discard commands if the unmap flag is set.
587          */
588         if (unlikely(flags & VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP)) {
589             err_status = VIRTIO_BLK_S_UNSUPP;
590             goto err;
591         }
592 
593         blk_aio_pdiscard(s->blk, sector << BDRV_SECTOR_BITS, bytes,
594                          virtio_blk_discard_write_zeroes_complete, req);
595     }
596 
597     return VIRTIO_BLK_S_OK;
598 
599 err:
600     if (is_write_zeroes) {
601         block_acct_invalid(blk_get_stats(s->blk), BLOCK_ACCT_WRITE);
602     }
603     return err_status;
604 }
605 
606 typedef struct ZoneCmdData {
607     VirtIOBlockReq *req;
608     struct iovec *in_iov;
609     unsigned in_num;
610     union {
611         struct {
612             unsigned int nr_zones;
613             BlockZoneDescriptor *zones;
614         } zone_report_data;
615         struct {
616             int64_t offset;
617         } zone_append_data;
618     };
619 } ZoneCmdData;
620 
621 /*
622  * check zoned_request: error checking before issuing requests. If all checks
623  * passed, return true.
624  * append: true if only zone append requests issued.
625  */
626 static bool check_zoned_request(VirtIOBlock *s, int64_t offset, int64_t len,
627                              bool append, uint8_t *status) {
628     BlockDriverState *bs = blk_bs(s->blk);
629     int index;
630 
631     if (!virtio_has_feature(s->host_features, VIRTIO_BLK_F_ZONED)) {
632         *status = VIRTIO_BLK_S_UNSUPP;
633         return false;
634     }
635 
636     if (offset < 0 || len < 0 || len > (bs->total_sectors << BDRV_SECTOR_BITS)
637         || offset > (bs->total_sectors << BDRV_SECTOR_BITS) - len) {
638         *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
639         return false;
640     }
641 
642     if (append) {
643         if (bs->bl.write_granularity) {
644             if ((offset % bs->bl.write_granularity) != 0) {
645                 *status = VIRTIO_BLK_S_ZONE_UNALIGNED_WP;
646                 return false;
647             }
648         }
649 
650         index = offset / bs->bl.zone_size;
651         if (BDRV_ZT_IS_CONV(bs->wps->wp[index])) {
652             *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
653             return false;
654         }
655 
656         if (len / 512 > bs->bl.max_append_sectors) {
657             if (bs->bl.max_append_sectors == 0) {
658                 *status = VIRTIO_BLK_S_UNSUPP;
659             } else {
660                 *status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
661             }
662             return false;
663         }
664     }
665     return true;
666 }
667 
668 static void virtio_blk_zone_report_complete(void *opaque, int ret)
669 {
670     ZoneCmdData *data = opaque;
671     VirtIOBlockReq *req = data->req;
672     VirtIOBlock *s = req->dev;
673     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
674     struct iovec *in_iov = data->in_iov;
675     unsigned in_num = data->in_num;
676     int64_t zrp_size, n, j = 0;
677     int64_t nz = data->zone_report_data.nr_zones;
678     int8_t err_status = VIRTIO_BLK_S_OK;
679 
680     trace_virtio_blk_zone_report_complete(vdev, req, nz, ret);
681     if (ret) {
682         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
683         goto out;
684     }
685 
686     struct virtio_blk_zone_report zrp_hdr = (struct virtio_blk_zone_report) {
687         .nr_zones = cpu_to_le64(nz),
688     };
689     zrp_size = sizeof(struct virtio_blk_zone_report)
690                + sizeof(struct virtio_blk_zone_descriptor) * nz;
691     n = iov_from_buf(in_iov, in_num, 0, &zrp_hdr, sizeof(zrp_hdr));
692     if (n != sizeof(zrp_hdr)) {
693         virtio_error(vdev, "Driver provided input buffer that is too small!");
694         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
695         goto out;
696     }
697 
698     for (size_t i = sizeof(zrp_hdr); i < zrp_size;
699         i += sizeof(struct virtio_blk_zone_descriptor), ++j) {
700         struct virtio_blk_zone_descriptor desc =
701             (struct virtio_blk_zone_descriptor) {
702                 .z_start = cpu_to_le64(data->zone_report_data.zones[j].start
703                     >> BDRV_SECTOR_BITS),
704                 .z_cap = cpu_to_le64(data->zone_report_data.zones[j].cap
705                     >> BDRV_SECTOR_BITS),
706                 .z_wp = cpu_to_le64(data->zone_report_data.zones[j].wp
707                     >> BDRV_SECTOR_BITS),
708         };
709 
710         switch (data->zone_report_data.zones[j].type) {
711         case BLK_ZT_CONV:
712             desc.z_type = VIRTIO_BLK_ZT_CONV;
713             break;
714         case BLK_ZT_SWR:
715             desc.z_type = VIRTIO_BLK_ZT_SWR;
716             break;
717         case BLK_ZT_SWP:
718             desc.z_type = VIRTIO_BLK_ZT_SWP;
719             break;
720         default:
721             g_assert_not_reached();
722         }
723 
724         switch (data->zone_report_data.zones[j].state) {
725         case BLK_ZS_RDONLY:
726             desc.z_state = VIRTIO_BLK_ZS_RDONLY;
727             break;
728         case BLK_ZS_OFFLINE:
729             desc.z_state = VIRTIO_BLK_ZS_OFFLINE;
730             break;
731         case BLK_ZS_EMPTY:
732             desc.z_state = VIRTIO_BLK_ZS_EMPTY;
733             break;
734         case BLK_ZS_CLOSED:
735             desc.z_state = VIRTIO_BLK_ZS_CLOSED;
736             break;
737         case BLK_ZS_FULL:
738             desc.z_state = VIRTIO_BLK_ZS_FULL;
739             break;
740         case BLK_ZS_EOPEN:
741             desc.z_state = VIRTIO_BLK_ZS_EOPEN;
742             break;
743         case BLK_ZS_IOPEN:
744             desc.z_state = VIRTIO_BLK_ZS_IOPEN;
745             break;
746         case BLK_ZS_NOT_WP:
747             desc.z_state = VIRTIO_BLK_ZS_NOT_WP;
748             break;
749         default:
750             g_assert_not_reached();
751         }
752 
753         /* TODO: it takes O(n^2) time complexity. Optimizations required. */
754         n = iov_from_buf(in_iov, in_num, i, &desc, sizeof(desc));
755         if (n != sizeof(desc)) {
756             virtio_error(vdev, "Driver provided input buffer "
757                                "for descriptors that is too small!");
758             err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
759         }
760     }
761 
762 out:
763     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
764     virtio_blk_req_complete(req, err_status);
765     virtio_blk_free_request(req);
766     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
767     g_free(data->zone_report_data.zones);
768     g_free(data);
769 }
770 
771 static void virtio_blk_handle_zone_report(VirtIOBlockReq *req,
772                                          struct iovec *in_iov,
773                                          unsigned in_num)
774 {
775     VirtIOBlock *s = req->dev;
776     VirtIODevice *vdev = VIRTIO_DEVICE(s);
777     unsigned int nr_zones;
778     ZoneCmdData *data;
779     int64_t zone_size, offset;
780     uint8_t err_status;
781 
782     if (req->in_len < sizeof(struct virtio_blk_inhdr) +
783             sizeof(struct virtio_blk_zone_report) +
784             sizeof(struct virtio_blk_zone_descriptor)) {
785         virtio_error(vdev, "in buffer too small for zone report");
786         return;
787     }
788 
789     /* start byte offset of the zone report */
790     offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
791     if (!check_zoned_request(s, offset, 0, false, &err_status)) {
792         goto out;
793     }
794     nr_zones = (req->in_len - sizeof(struct virtio_blk_inhdr) -
795                 sizeof(struct virtio_blk_zone_report)) /
796                sizeof(struct virtio_blk_zone_descriptor);
797     trace_virtio_blk_handle_zone_report(vdev, req,
798                                         offset >> BDRV_SECTOR_BITS, nr_zones);
799 
800     zone_size = sizeof(BlockZoneDescriptor) * nr_zones;
801     data = g_malloc(sizeof(ZoneCmdData));
802     data->req = req;
803     data->in_iov = in_iov;
804     data->in_num = in_num;
805     data->zone_report_data.nr_zones = nr_zones;
806     data->zone_report_data.zones = g_malloc(zone_size),
807 
808     blk_aio_zone_report(s->blk, offset, &data->zone_report_data.nr_zones,
809                         data->zone_report_data.zones,
810                         virtio_blk_zone_report_complete, data);
811     return;
812 out:
813     virtio_blk_req_complete(req, err_status);
814     virtio_blk_free_request(req);
815 }
816 
817 static void virtio_blk_zone_mgmt_complete(void *opaque, int ret)
818 {
819     VirtIOBlockReq *req = opaque;
820     VirtIOBlock *s = req->dev;
821     VirtIODevice *vdev = VIRTIO_DEVICE(s);
822     int8_t err_status = VIRTIO_BLK_S_OK;
823     trace_virtio_blk_zone_mgmt_complete(vdev, req,ret);
824 
825     if (ret) {
826         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
827     }
828 
829     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
830     virtio_blk_req_complete(req, err_status);
831     virtio_blk_free_request(req);
832     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
833 }
834 
835 static int virtio_blk_handle_zone_mgmt(VirtIOBlockReq *req, BlockZoneOp op)
836 {
837     VirtIOBlock *s = req->dev;
838     VirtIODevice *vdev = VIRTIO_DEVICE(s);
839     BlockDriverState *bs = blk_bs(s->blk);
840     int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
841     uint64_t len;
842     uint64_t capacity = bs->total_sectors << BDRV_SECTOR_BITS;
843     uint8_t err_status = VIRTIO_BLK_S_OK;
844 
845     uint32_t type = virtio_ldl_p(vdev, &req->out.type);
846     if (type == VIRTIO_BLK_T_ZONE_RESET_ALL) {
847         /* Entire drive capacity */
848         offset = 0;
849         len = capacity;
850         trace_virtio_blk_handle_zone_reset_all(vdev, req, 0,
851                                                bs->total_sectors);
852     } else {
853         if (bs->bl.zone_size > capacity - offset) {
854             /* The zoned device allows the last smaller zone. */
855             len = capacity - bs->bl.zone_size * (bs->bl.nr_zones - 1);
856         } else {
857             len = bs->bl.zone_size;
858         }
859         trace_virtio_blk_handle_zone_mgmt(vdev, req, op,
860                                           offset >> BDRV_SECTOR_BITS,
861                                           len >> BDRV_SECTOR_BITS);
862     }
863 
864     if (!check_zoned_request(s, offset, len, false, &err_status)) {
865         goto out;
866     }
867 
868     blk_aio_zone_mgmt(s->blk, op, offset, len,
869                       virtio_blk_zone_mgmt_complete, req);
870 
871     return 0;
872 out:
873     virtio_blk_req_complete(req, err_status);
874     virtio_blk_free_request(req);
875     return err_status;
876 }
877 
878 static void virtio_blk_zone_append_complete(void *opaque, int ret)
879 {
880     ZoneCmdData *data = opaque;
881     VirtIOBlockReq *req = data->req;
882     VirtIOBlock *s = req->dev;
883     VirtIODevice *vdev = VIRTIO_DEVICE(req->dev);
884     int64_t append_sector, n;
885     uint8_t err_status = VIRTIO_BLK_S_OK;
886 
887     if (ret) {
888         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
889         goto out;
890     }
891 
892     virtio_stq_p(vdev, &append_sector,
893                  data->zone_append_data.offset >> BDRV_SECTOR_BITS);
894     n = iov_from_buf(data->in_iov, data->in_num, 0, &append_sector,
895                      sizeof(append_sector));
896     if (n != sizeof(append_sector)) {
897         virtio_error(vdev, "Driver provided input buffer less than size of "
898                            "append_sector");
899         err_status = VIRTIO_BLK_S_ZONE_INVALID_CMD;
900         goto out;
901     }
902     trace_virtio_blk_zone_append_complete(vdev, req, append_sector, ret);
903 
904 out:
905     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
906     virtio_blk_req_complete(req, err_status);
907     virtio_blk_free_request(req);
908     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
909     g_free(data);
910 }
911 
912 static int virtio_blk_handle_zone_append(VirtIOBlockReq *req,
913                                          struct iovec *out_iov,
914                                          struct iovec *in_iov,
915                                          uint64_t out_num,
916                                          unsigned in_num) {
917     VirtIOBlock *s = req->dev;
918     VirtIODevice *vdev = VIRTIO_DEVICE(s);
919     uint8_t err_status = VIRTIO_BLK_S_OK;
920 
921     int64_t offset = virtio_ldq_p(vdev, &req->out.sector) << BDRV_SECTOR_BITS;
922     int64_t len = iov_size(out_iov, out_num);
923 
924     trace_virtio_blk_handle_zone_append(vdev, req, offset >> BDRV_SECTOR_BITS);
925     if (!check_zoned_request(s, offset, len, true, &err_status)) {
926         goto out;
927     }
928 
929     ZoneCmdData *data = g_malloc(sizeof(ZoneCmdData));
930     data->req = req;
931     data->in_iov = in_iov;
932     data->in_num = in_num;
933     data->zone_append_data.offset = offset;
934     qemu_iovec_init_external(&req->qiov, out_iov, out_num);
935 
936     block_acct_start(blk_get_stats(s->blk), &req->acct, len,
937                      BLOCK_ACCT_ZONE_APPEND);
938 
939     blk_aio_zone_append(s->blk, &data->zone_append_data.offset, &req->qiov, 0,
940                         virtio_blk_zone_append_complete, data);
941     return 0;
942 
943 out:
944     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
945     virtio_blk_req_complete(req, err_status);
946     virtio_blk_free_request(req);
947     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
948     return err_status;
949 }
950 
951 static int virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb)
952 {
953     uint32_t type;
954     struct iovec *in_iov = req->elem.in_sg;
955     struct iovec *out_iov = req->elem.out_sg;
956     unsigned in_num = req->elem.in_num;
957     unsigned out_num = req->elem.out_num;
958     VirtIOBlock *s = req->dev;
959     VirtIODevice *vdev = VIRTIO_DEVICE(s);
960 
961     if (req->elem.out_num < 1 || req->elem.in_num < 1) {
962         virtio_error(vdev, "virtio-blk missing headers");
963         return -1;
964     }
965 
966     if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
967                             sizeof(req->out)) != sizeof(req->out))) {
968         virtio_error(vdev, "virtio-blk request outhdr too short");
969         return -1;
970     }
971 
972     iov_discard_front_undoable(&out_iov, &out_num, sizeof(req->out),
973                                &req->outhdr_undo);
974 
975     if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
976         virtio_error(vdev, "virtio-blk request inhdr too short");
977         iov_discard_undo(&req->outhdr_undo);
978         return -1;
979     }
980 
981     /* We always touch the last byte, so just see how big in_iov is.  */
982     req->in_len = iov_size(in_iov, in_num);
983     req->in = (void *)in_iov[in_num - 1].iov_base
984               + in_iov[in_num - 1].iov_len
985               - sizeof(struct virtio_blk_inhdr);
986     iov_discard_back_undoable(in_iov, &in_num, sizeof(struct virtio_blk_inhdr),
987                               &req->inhdr_undo);
988 
989     type = virtio_ldl_p(vdev, &req->out.type);
990 
991     /* VIRTIO_BLK_T_OUT defines the command direction. VIRTIO_BLK_T_BARRIER
992      * is an optional flag. Although a guest should not send this flag if
993      * not negotiated we ignored it in the past. So keep ignoring it. */
994     switch (type & ~(VIRTIO_BLK_T_OUT | VIRTIO_BLK_T_BARRIER)) {
995     case VIRTIO_BLK_T_IN:
996     {
997         bool is_write = type & VIRTIO_BLK_T_OUT;
998         req->sector_num = virtio_ldq_p(vdev, &req->out.sector);
999 
1000         if (is_write) {
1001             qemu_iovec_init_external(&req->qiov, out_iov, out_num);
1002             trace_virtio_blk_handle_write(vdev, req, req->sector_num,
1003                                           req->qiov.size / BDRV_SECTOR_SIZE);
1004         } else {
1005             qemu_iovec_init_external(&req->qiov, in_iov, in_num);
1006             trace_virtio_blk_handle_read(vdev, req, req->sector_num,
1007                                          req->qiov.size / BDRV_SECTOR_SIZE);
1008         }
1009 
1010         if (!virtio_blk_sect_range_ok(s, req->sector_num, req->qiov.size)) {
1011             virtio_blk_req_complete(req, VIRTIO_BLK_S_IOERR);
1012             block_acct_invalid(blk_get_stats(s->blk),
1013                                is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
1014             virtio_blk_free_request(req);
1015             return 0;
1016         }
1017 
1018         block_acct_start(blk_get_stats(s->blk), &req->acct, req->qiov.size,
1019                          is_write ? BLOCK_ACCT_WRITE : BLOCK_ACCT_READ);
1020 
1021         /* merge would exceed maximum number of requests or IO direction
1022          * changes */
1023         if (mrb->num_reqs > 0 && (mrb->num_reqs == VIRTIO_BLK_MAX_MERGE_REQS ||
1024                                   is_write != mrb->is_write ||
1025                                   !s->conf.request_merging)) {
1026             virtio_blk_submit_multireq(s, mrb);
1027         }
1028 
1029         assert(mrb->num_reqs < VIRTIO_BLK_MAX_MERGE_REQS);
1030         mrb->reqs[mrb->num_reqs++] = req;
1031         mrb->is_write = is_write;
1032         break;
1033     }
1034     case VIRTIO_BLK_T_FLUSH:
1035         virtio_blk_handle_flush(req, mrb);
1036         break;
1037     case VIRTIO_BLK_T_ZONE_REPORT:
1038         virtio_blk_handle_zone_report(req, in_iov, in_num);
1039         break;
1040     case VIRTIO_BLK_T_ZONE_OPEN:
1041         virtio_blk_handle_zone_mgmt(req, BLK_ZO_OPEN);
1042         break;
1043     case VIRTIO_BLK_T_ZONE_CLOSE:
1044         virtio_blk_handle_zone_mgmt(req, BLK_ZO_CLOSE);
1045         break;
1046     case VIRTIO_BLK_T_ZONE_FINISH:
1047         virtio_blk_handle_zone_mgmt(req, BLK_ZO_FINISH);
1048         break;
1049     case VIRTIO_BLK_T_ZONE_RESET:
1050         virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
1051         break;
1052     case VIRTIO_BLK_T_ZONE_RESET_ALL:
1053         virtio_blk_handle_zone_mgmt(req, BLK_ZO_RESET);
1054         break;
1055     case VIRTIO_BLK_T_SCSI_CMD:
1056         virtio_blk_handle_scsi(req);
1057         break;
1058     case VIRTIO_BLK_T_GET_ID:
1059     {
1060         /*
1061          * NB: per existing s/n string convention the string is
1062          * terminated by '\0' only when shorter than buffer.
1063          */
1064         const char *serial = s->conf.serial ? s->conf.serial : "";
1065         size_t size = MIN(strlen(serial) + 1,
1066                           MIN(iov_size(in_iov, in_num),
1067                               VIRTIO_BLK_ID_BYTES));
1068         iov_from_buf(in_iov, in_num, 0, serial, size);
1069         virtio_blk_req_complete(req, VIRTIO_BLK_S_OK);
1070         virtio_blk_free_request(req);
1071         break;
1072     }
1073     case VIRTIO_BLK_T_ZONE_APPEND & ~VIRTIO_BLK_T_OUT:
1074         /*
1075          * Passing out_iov/out_num and in_iov/in_num is not safe
1076          * to access req->elem.out_sg directly because it may be
1077          * modified by virtio_blk_handle_request().
1078          */
1079         virtio_blk_handle_zone_append(req, out_iov, in_iov, out_num, in_num);
1080         break;
1081     /*
1082      * VIRTIO_BLK_T_DISCARD and VIRTIO_BLK_T_WRITE_ZEROES are defined with
1083      * VIRTIO_BLK_T_OUT flag set. We masked this flag in the switch statement,
1084      * so we must mask it for these requests, then we will check if it is set.
1085      */
1086     case VIRTIO_BLK_T_DISCARD & ~VIRTIO_BLK_T_OUT:
1087     case VIRTIO_BLK_T_WRITE_ZEROES & ~VIRTIO_BLK_T_OUT:
1088     {
1089         struct virtio_blk_discard_write_zeroes dwz_hdr;
1090         size_t out_len = iov_size(out_iov, out_num);
1091         bool is_write_zeroes = (type & ~VIRTIO_BLK_T_BARRIER) ==
1092                                VIRTIO_BLK_T_WRITE_ZEROES;
1093         uint8_t err_status;
1094 
1095         /*
1096          * Unsupported if VIRTIO_BLK_T_OUT is not set or the request contains
1097          * more than one segment.
1098          */
1099         if (unlikely(!(type & VIRTIO_BLK_T_OUT) ||
1100                      out_len > sizeof(dwz_hdr))) {
1101             virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
1102             virtio_blk_free_request(req);
1103             return 0;
1104         }
1105 
1106         if (unlikely(iov_to_buf(out_iov, out_num, 0, &dwz_hdr,
1107                                 sizeof(dwz_hdr)) != sizeof(dwz_hdr))) {
1108             iov_discard_undo(&req->inhdr_undo);
1109             iov_discard_undo(&req->outhdr_undo);
1110             virtio_error(vdev, "virtio-blk discard/write_zeroes header"
1111                          " too short");
1112             return -1;
1113         }
1114 
1115         err_status = virtio_blk_handle_discard_write_zeroes(req, &dwz_hdr,
1116                                                             is_write_zeroes);
1117         if (err_status != VIRTIO_BLK_S_OK) {
1118             virtio_blk_req_complete(req, err_status);
1119             virtio_blk_free_request(req);
1120         }
1121 
1122         break;
1123     }
1124     default:
1125         virtio_blk_req_complete(req, VIRTIO_BLK_S_UNSUPP);
1126         virtio_blk_free_request(req);
1127     }
1128     return 0;
1129 }
1130 
1131 void virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq)
1132 {
1133     VirtIOBlockReq *req;
1134     MultiReqBuffer mrb = {};
1135     bool suppress_notifications = virtio_queue_get_notification(vq);
1136 
1137     aio_context_acquire(blk_get_aio_context(s->blk));
1138     defer_call_begin();
1139 
1140     do {
1141         if (suppress_notifications) {
1142             virtio_queue_set_notification(vq, 0);
1143         }
1144 
1145         while ((req = virtio_blk_get_request(s, vq))) {
1146             if (virtio_blk_handle_request(req, &mrb)) {
1147                 virtqueue_detach_element(req->vq, &req->elem, 0);
1148                 virtio_blk_free_request(req);
1149                 break;
1150             }
1151         }
1152 
1153         if (suppress_notifications) {
1154             virtio_queue_set_notification(vq, 1);
1155         }
1156     } while (!virtio_queue_empty(vq));
1157 
1158     if (mrb.num_reqs) {
1159         virtio_blk_submit_multireq(s, &mrb);
1160     }
1161 
1162     defer_call_end();
1163     aio_context_release(blk_get_aio_context(s->blk));
1164 }
1165 
1166 static void virtio_blk_handle_output(VirtIODevice *vdev, VirtQueue *vq)
1167 {
1168     VirtIOBlock *s = (VirtIOBlock *)vdev;
1169 
1170     if (s->dataplane && !s->dataplane_started) {
1171         /* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
1172          * dataplane here instead of waiting for .set_status().
1173          */
1174         virtio_device_start_ioeventfd(vdev);
1175         if (!s->dataplane_disabled) {
1176             return;
1177         }
1178     }
1179     virtio_blk_handle_vq(s, vq);
1180 }
1181 
1182 static void virtio_blk_dma_restart_bh(void *opaque)
1183 {
1184     VirtIOBlock *s = opaque;
1185 
1186     VirtIOBlockReq *req = s->rq;
1187     MultiReqBuffer mrb = {};
1188 
1189     s->rq = NULL;
1190 
1191     aio_context_acquire(blk_get_aio_context(s->conf.conf.blk));
1192     while (req) {
1193         VirtIOBlockReq *next = req->next;
1194         if (virtio_blk_handle_request(req, &mrb)) {
1195             /* Device is now broken and won't do any processing until it gets
1196              * reset. Already queued requests will be lost: let's purge them.
1197              */
1198             while (req) {
1199                 next = req->next;
1200                 virtqueue_detach_element(req->vq, &req->elem, 0);
1201                 virtio_blk_free_request(req);
1202                 req = next;
1203             }
1204             break;
1205         }
1206         req = next;
1207     }
1208 
1209     if (mrb.num_reqs) {
1210         virtio_blk_submit_multireq(s, &mrb);
1211     }
1212 
1213     /* Paired with inc in virtio_blk_dma_restart_cb() */
1214     blk_dec_in_flight(s->conf.conf.blk);
1215 
1216     aio_context_release(blk_get_aio_context(s->conf.conf.blk));
1217 }
1218 
1219 static void virtio_blk_dma_restart_cb(void *opaque, bool running,
1220                                       RunState state)
1221 {
1222     VirtIOBlock *s = opaque;
1223 
1224     if (!running) {
1225         return;
1226     }
1227 
1228     /* Paired with dec in virtio_blk_dma_restart_bh() */
1229     blk_inc_in_flight(s->conf.conf.blk);
1230 
1231     aio_bh_schedule_oneshot(blk_get_aio_context(s->conf.conf.blk),
1232             virtio_blk_dma_restart_bh, s);
1233 }
1234 
1235 static void virtio_blk_reset(VirtIODevice *vdev)
1236 {
1237     VirtIOBlock *s = VIRTIO_BLK(vdev);
1238     AioContext *ctx;
1239     VirtIOBlockReq *req;
1240 
1241     ctx = blk_get_aio_context(s->blk);
1242     aio_context_acquire(ctx);
1243     blk_drain(s->blk);
1244 
1245     /* We drop queued requests after blk_drain() because blk_drain() itself can
1246      * produce them. */
1247     while (s->rq) {
1248         req = s->rq;
1249         s->rq = req->next;
1250         virtqueue_detach_element(req->vq, &req->elem, 0);
1251         virtio_blk_free_request(req);
1252     }
1253 
1254     aio_context_release(ctx);
1255 
1256     assert(!s->dataplane_started);
1257     blk_set_enable_write_cache(s->blk, s->original_wce);
1258 }
1259 
1260 /* coalesce internal state, copy to pci i/o region 0
1261  */
1262 static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
1263 {
1264     VirtIOBlock *s = VIRTIO_BLK(vdev);
1265     BlockConf *conf = &s->conf.conf;
1266     BlockDriverState *bs = blk_bs(s->blk);
1267     struct virtio_blk_config blkcfg;
1268     uint64_t capacity;
1269     int64_t length;
1270     int blk_size = conf->logical_block_size;
1271     AioContext *ctx;
1272 
1273     ctx = blk_get_aio_context(s->blk);
1274     aio_context_acquire(ctx);
1275 
1276     blk_get_geometry(s->blk, &capacity);
1277     memset(&blkcfg, 0, sizeof(blkcfg));
1278     virtio_stq_p(vdev, &blkcfg.capacity, capacity);
1279     virtio_stl_p(vdev, &blkcfg.seg_max,
1280                  s->conf.seg_max_adjust ? s->conf.queue_size - 2 : 128 - 2);
1281     virtio_stw_p(vdev, &blkcfg.geometry.cylinders, conf->cyls);
1282     virtio_stl_p(vdev, &blkcfg.blk_size, blk_size);
1283     virtio_stw_p(vdev, &blkcfg.min_io_size, conf->min_io_size / blk_size);
1284     virtio_stl_p(vdev, &blkcfg.opt_io_size, conf->opt_io_size / blk_size);
1285     blkcfg.geometry.heads = conf->heads;
1286     /*
1287      * We must ensure that the block device capacity is a multiple of
1288      * the logical block size. If that is not the case, let's use
1289      * sector_mask to adopt the geometry to have a correct picture.
1290      * For those devices where the capacity is ok for the given geometry
1291      * we don't touch the sector value of the geometry, since some devices
1292      * (like s390 dasd) need a specific value. Here the capacity is already
1293      * cyls*heads*secs*blk_size and the sector value is not block size
1294      * divided by 512 - instead it is the amount of blk_size blocks
1295      * per track (cylinder).
1296      */
1297     length = blk_getlength(s->blk);
1298     aio_context_release(ctx);
1299     if (length > 0 && length / conf->heads / conf->secs % blk_size) {
1300         blkcfg.geometry.sectors = conf->secs & ~s->sector_mask;
1301     } else {
1302         blkcfg.geometry.sectors = conf->secs;
1303     }
1304     blkcfg.size_max = 0;
1305     blkcfg.physical_block_exp = get_physical_block_exp(conf);
1306     blkcfg.alignment_offset = 0;
1307     blkcfg.wce = blk_enable_write_cache(s->blk);
1308     virtio_stw_p(vdev, &blkcfg.num_queues, s->conf.num_queues);
1309     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD)) {
1310         uint32_t discard_granularity = conf->discard_granularity;
1311         if (discard_granularity == -1 || !s->conf.report_discard_granularity) {
1312             discard_granularity = blk_size;
1313         }
1314         virtio_stl_p(vdev, &blkcfg.max_discard_sectors,
1315                      s->conf.max_discard_sectors);
1316         virtio_stl_p(vdev, &blkcfg.discard_sector_alignment,
1317                      discard_granularity >> BDRV_SECTOR_BITS);
1318         /*
1319          * We support only one segment per request since multiple segments
1320          * are not widely used and there are no userspace APIs that allow
1321          * applications to submit multiple segments in a single call.
1322          */
1323         virtio_stl_p(vdev, &blkcfg.max_discard_seg, 1);
1324     }
1325     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES)) {
1326         virtio_stl_p(vdev, &blkcfg.max_write_zeroes_sectors,
1327                      s->conf.max_write_zeroes_sectors);
1328         blkcfg.write_zeroes_may_unmap = 1;
1329         virtio_stl_p(vdev, &blkcfg.max_write_zeroes_seg, 1);
1330     }
1331     if (bs->bl.zoned != BLK_Z_NONE) {
1332         switch (bs->bl.zoned) {
1333         case BLK_Z_HM:
1334             blkcfg.zoned.model = VIRTIO_BLK_Z_HM;
1335             break;
1336         case BLK_Z_HA:
1337             blkcfg.zoned.model = VIRTIO_BLK_Z_HA;
1338             break;
1339         default:
1340             g_assert_not_reached();
1341         }
1342 
1343         virtio_stl_p(vdev, &blkcfg.zoned.zone_sectors,
1344                      bs->bl.zone_size / 512);
1345         virtio_stl_p(vdev, &blkcfg.zoned.max_active_zones,
1346                      bs->bl.max_active_zones);
1347         virtio_stl_p(vdev, &blkcfg.zoned.max_open_zones,
1348                      bs->bl.max_open_zones);
1349         virtio_stl_p(vdev, &blkcfg.zoned.write_granularity, blk_size);
1350         virtio_stl_p(vdev, &blkcfg.zoned.max_append_sectors,
1351                      bs->bl.max_append_sectors);
1352     } else {
1353         blkcfg.zoned.model = VIRTIO_BLK_Z_NONE;
1354     }
1355     memcpy(config, &blkcfg, s->config_size);
1356 }
1357 
1358 static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
1359 {
1360     VirtIOBlock *s = VIRTIO_BLK(vdev);
1361     struct virtio_blk_config blkcfg;
1362 
1363     memcpy(&blkcfg, config, s->config_size);
1364 
1365     aio_context_acquire(blk_get_aio_context(s->blk));
1366     blk_set_enable_write_cache(s->blk, blkcfg.wce != 0);
1367     aio_context_release(blk_get_aio_context(s->blk));
1368 }
1369 
1370 static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features,
1371                                         Error **errp)
1372 {
1373     VirtIOBlock *s = VIRTIO_BLK(vdev);
1374 
1375     /* Firstly sync all virtio-blk possible supported features */
1376     features |= s->host_features;
1377 
1378     virtio_add_feature(&features, VIRTIO_BLK_F_SEG_MAX);
1379     virtio_add_feature(&features, VIRTIO_BLK_F_GEOMETRY);
1380     virtio_add_feature(&features, VIRTIO_BLK_F_TOPOLOGY);
1381     virtio_add_feature(&features, VIRTIO_BLK_F_BLK_SIZE);
1382     if (virtio_has_feature(features, VIRTIO_F_VERSION_1)) {
1383         if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_SCSI)) {
1384             error_setg(errp, "Please set scsi=off for virtio-blk devices in order to use virtio 1.0");
1385             return 0;
1386         }
1387     } else {
1388         virtio_clear_feature(&features, VIRTIO_F_ANY_LAYOUT);
1389         virtio_add_feature(&features, VIRTIO_BLK_F_SCSI);
1390     }
1391 
1392     if (blk_enable_write_cache(s->blk) ||
1393         (s->conf.x_enable_wce_if_config_wce &&
1394          virtio_has_feature(features, VIRTIO_BLK_F_CONFIG_WCE))) {
1395         virtio_add_feature(&features, VIRTIO_BLK_F_WCE);
1396     }
1397     if (!blk_is_writable(s->blk)) {
1398         virtio_add_feature(&features, VIRTIO_BLK_F_RO);
1399     }
1400     if (s->conf.num_queues > 1) {
1401         virtio_add_feature(&features, VIRTIO_BLK_F_MQ);
1402     }
1403 
1404     return features;
1405 }
1406 
1407 static void virtio_blk_set_status(VirtIODevice *vdev, uint8_t status)
1408 {
1409     VirtIOBlock *s = VIRTIO_BLK(vdev);
1410 
1411     if (!(status & (VIRTIO_CONFIG_S_DRIVER | VIRTIO_CONFIG_S_DRIVER_OK))) {
1412         assert(!s->dataplane_started);
1413     }
1414 
1415     if (!(status & VIRTIO_CONFIG_S_DRIVER_OK)) {
1416         return;
1417     }
1418 
1419     /* A guest that supports VIRTIO_BLK_F_CONFIG_WCE must be able to send
1420      * cache flushes.  Thus, the "auto writethrough" behavior is never
1421      * necessary for guests that support the VIRTIO_BLK_F_CONFIG_WCE feature.
1422      * Leaving it enabled would break the following sequence:
1423      *
1424      *     Guest started with "-drive cache=writethrough"
1425      *     Guest sets status to 0
1426      *     Guest sets DRIVER bit in status field
1427      *     Guest reads host features (WCE=0, CONFIG_WCE=1)
1428      *     Guest writes guest features (WCE=0, CONFIG_WCE=1)
1429      *     Guest writes 1 to the WCE configuration field (writeback mode)
1430      *     Guest sets DRIVER_OK bit in status field
1431      *
1432      * s->blk would erroneously be placed in writethrough mode.
1433      */
1434     if (!virtio_vdev_has_feature(vdev, VIRTIO_BLK_F_CONFIG_WCE)) {
1435         aio_context_acquire(blk_get_aio_context(s->blk));
1436         blk_set_enable_write_cache(s->blk,
1437                                    virtio_vdev_has_feature(vdev,
1438                                                            VIRTIO_BLK_F_WCE));
1439         aio_context_release(blk_get_aio_context(s->blk));
1440     }
1441 }
1442 
1443 static void virtio_blk_save_device(VirtIODevice *vdev, QEMUFile *f)
1444 {
1445     VirtIOBlock *s = VIRTIO_BLK(vdev);
1446     VirtIOBlockReq *req = s->rq;
1447 
1448     while (req) {
1449         qemu_put_sbyte(f, 1);
1450 
1451         if (s->conf.num_queues > 1) {
1452             qemu_put_be32(f, virtio_get_queue_index(req->vq));
1453         }
1454 
1455         qemu_put_virtqueue_element(vdev, f, &req->elem);
1456         req = req->next;
1457     }
1458     qemu_put_sbyte(f, 0);
1459 }
1460 
1461 static int virtio_blk_load_device(VirtIODevice *vdev, QEMUFile *f,
1462                                   int version_id)
1463 {
1464     VirtIOBlock *s = VIRTIO_BLK(vdev);
1465 
1466     while (qemu_get_sbyte(f)) {
1467         unsigned nvqs = s->conf.num_queues;
1468         unsigned vq_idx = 0;
1469         VirtIOBlockReq *req;
1470 
1471         if (nvqs > 1) {
1472             vq_idx = qemu_get_be32(f);
1473 
1474             if (vq_idx >= nvqs) {
1475                 error_report("Invalid virtqueue index in request list: %#x",
1476                              vq_idx);
1477                 return -EINVAL;
1478             }
1479         }
1480 
1481         req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOBlockReq));
1482         virtio_blk_init_request(s, virtio_get_queue(vdev, vq_idx), req);
1483         req->next = s->rq;
1484         s->rq = req;
1485     }
1486 
1487     return 0;
1488 }
1489 
1490 static void virtio_resize_cb(void *opaque)
1491 {
1492     VirtIODevice *vdev = opaque;
1493 
1494     assert(qemu_get_current_aio_context() == qemu_get_aio_context());
1495     virtio_notify_config(vdev);
1496 }
1497 
1498 static void virtio_blk_resize(void *opaque)
1499 {
1500     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
1501 
1502     /*
1503      * virtio_notify_config() needs to acquire the global mutex,
1504      * so it can't be called from an iothread. Instead, schedule
1505      * it to be run in the main context BH.
1506      */
1507     aio_bh_schedule_oneshot(qemu_get_aio_context(), virtio_resize_cb, vdev);
1508 }
1509 
1510 /* Suspend virtqueue ioeventfd processing during drain */
1511 static void virtio_blk_drained_begin(void *opaque)
1512 {
1513     VirtIOBlock *s = opaque;
1514     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
1515     AioContext *ctx = blk_get_aio_context(s->conf.conf.blk);
1516 
1517     if (!s->dataplane || !s->dataplane_started) {
1518         return;
1519     }
1520 
1521     for (uint16_t i = 0; i < s->conf.num_queues; i++) {
1522         VirtQueue *vq = virtio_get_queue(vdev, i);
1523         virtio_queue_aio_detach_host_notifier(vq, ctx);
1524     }
1525 }
1526 
1527 /* Resume virtqueue ioeventfd processing after drain */
1528 static void virtio_blk_drained_end(void *opaque)
1529 {
1530     VirtIOBlock *s = opaque;
1531     VirtIODevice *vdev = VIRTIO_DEVICE(opaque);
1532     AioContext *ctx = blk_get_aio_context(s->conf.conf.blk);
1533 
1534     if (!s->dataplane || !s->dataplane_started) {
1535         return;
1536     }
1537 
1538     for (uint16_t i = 0; i < s->conf.num_queues; i++) {
1539         VirtQueue *vq = virtio_get_queue(vdev, i);
1540         virtio_queue_aio_attach_host_notifier(vq, ctx);
1541     }
1542 }
1543 
1544 static const BlockDevOps virtio_block_ops = {
1545     .resize_cb     = virtio_blk_resize,
1546     .drained_begin = virtio_blk_drained_begin,
1547     .drained_end   = virtio_blk_drained_end,
1548 };
1549 
1550 static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
1551 {
1552     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1553     VirtIOBlock *s = VIRTIO_BLK(dev);
1554     VirtIOBlkConf *conf = &s->conf;
1555     Error *err = NULL;
1556     unsigned i;
1557 
1558     if (!conf->conf.blk) {
1559         error_setg(errp, "drive property not set");
1560         return;
1561     }
1562     if (!blk_is_inserted(conf->conf.blk)) {
1563         error_setg(errp, "Device needs media, but drive is empty");
1564         return;
1565     }
1566     if (conf->num_queues == VIRTIO_BLK_AUTO_NUM_QUEUES) {
1567         conf->num_queues = 1;
1568     }
1569     if (!conf->num_queues) {
1570         error_setg(errp, "num-queues property must be larger than 0");
1571         return;
1572     }
1573     if (conf->queue_size <= 2) {
1574         error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1575                    "must be > 2", conf->queue_size);
1576         return;
1577     }
1578     if (!is_power_of_2(conf->queue_size) ||
1579         conf->queue_size > VIRTQUEUE_MAX_SIZE) {
1580         error_setg(errp, "invalid queue-size property (%" PRIu16 "), "
1581                    "must be a power of 2 (max %d)",
1582                    conf->queue_size, VIRTQUEUE_MAX_SIZE);
1583         return;
1584     }
1585 
1586     if (!blkconf_apply_backend_options(&conf->conf,
1587                                        !blk_supports_write_perm(conf->conf.blk),
1588                                        true, errp)) {
1589         return;
1590     }
1591     s->original_wce = blk_enable_write_cache(conf->conf.blk);
1592     if (!blkconf_geometry(&conf->conf, NULL, 65535, 255, 255, errp)) {
1593         return;
1594     }
1595 
1596     if (!blkconf_blocksizes(&conf->conf, errp)) {
1597         return;
1598     }
1599 
1600     BlockDriverState *bs = blk_bs(conf->conf.blk);
1601     if (bs->bl.zoned != BLK_Z_NONE) {
1602         virtio_add_feature(&s->host_features, VIRTIO_BLK_F_ZONED);
1603         if (bs->bl.zoned == BLK_Z_HM) {
1604             virtio_clear_feature(&s->host_features, VIRTIO_BLK_F_DISCARD);
1605         }
1606     }
1607 
1608     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_DISCARD) &&
1609         (!conf->max_discard_sectors ||
1610          conf->max_discard_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1611         error_setg(errp, "invalid max-discard-sectors property (%" PRIu32 ")"
1612                    ", must be between 1 and %d",
1613                    conf->max_discard_sectors, (int)BDRV_REQUEST_MAX_SECTORS);
1614         return;
1615     }
1616 
1617     if (virtio_has_feature(s->host_features, VIRTIO_BLK_F_WRITE_ZEROES) &&
1618         (!conf->max_write_zeroes_sectors ||
1619          conf->max_write_zeroes_sectors > BDRV_REQUEST_MAX_SECTORS)) {
1620         error_setg(errp, "invalid max-write-zeroes-sectors property (%" PRIu32
1621                    "), must be between 1 and %d",
1622                    conf->max_write_zeroes_sectors,
1623                    (int)BDRV_REQUEST_MAX_SECTORS);
1624         return;
1625     }
1626 
1627     s->config_size = virtio_get_config_size(&virtio_blk_cfg_size_params,
1628                                             s->host_features);
1629     virtio_init(vdev, VIRTIO_ID_BLOCK, s->config_size);
1630 
1631     s->blk = conf->conf.blk;
1632     s->rq = NULL;
1633     s->sector_mask = (s->conf.conf.logical_block_size / BDRV_SECTOR_SIZE) - 1;
1634 
1635     for (i = 0; i < conf->num_queues; i++) {
1636         virtio_add_queue(vdev, conf->queue_size, virtio_blk_handle_output);
1637     }
1638     qemu_coroutine_inc_pool_size(conf->num_queues * conf->queue_size / 2);
1639     virtio_blk_data_plane_create(vdev, conf, &s->dataplane, &err);
1640     if (err != NULL) {
1641         error_propagate(errp, err);
1642         for (i = 0; i < conf->num_queues; i++) {
1643             virtio_del_queue(vdev, i);
1644         }
1645         virtio_cleanup(vdev);
1646         return;
1647     }
1648 
1649     /*
1650      * This must be after virtio_init() so virtio_blk_dma_restart_cb() gets
1651      * called after ->start_ioeventfd() has already set blk's AioContext.
1652      */
1653     s->change =
1654         qdev_add_vm_change_state_handler(dev, virtio_blk_dma_restart_cb, s);
1655 
1656     blk_ram_registrar_init(&s->blk_ram_registrar, s->blk);
1657     blk_set_dev_ops(s->blk, &virtio_block_ops, s);
1658 
1659     blk_iostatus_enable(s->blk);
1660 
1661     add_boot_device_lchs(dev, "/disk@0,0",
1662                          conf->conf.lcyls,
1663                          conf->conf.lheads,
1664                          conf->conf.lsecs);
1665 }
1666 
1667 static void virtio_blk_device_unrealize(DeviceState *dev)
1668 {
1669     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
1670     VirtIOBlock *s = VIRTIO_BLK(dev);
1671     VirtIOBlkConf *conf = &s->conf;
1672     unsigned i;
1673 
1674     blk_drain(s->blk);
1675     del_boot_device_lchs(dev, "/disk@0,0");
1676     virtio_blk_data_plane_destroy(s->dataplane);
1677     s->dataplane = NULL;
1678     for (i = 0; i < conf->num_queues; i++) {
1679         virtio_del_queue(vdev, i);
1680     }
1681     qemu_coroutine_dec_pool_size(conf->num_queues * conf->queue_size / 2);
1682     blk_ram_registrar_destroy(&s->blk_ram_registrar);
1683     qemu_del_vm_change_state_handler(s->change);
1684     blockdev_mark_auto_del(s->blk);
1685     virtio_cleanup(vdev);
1686 }
1687 
1688 static void virtio_blk_instance_init(Object *obj)
1689 {
1690     VirtIOBlock *s = VIRTIO_BLK(obj);
1691 
1692     device_add_bootindex_property(obj, &s->conf.conf.bootindex,
1693                                   "bootindex", "/disk@0,0",
1694                                   DEVICE(obj));
1695 }
1696 
1697 static const VMStateDescription vmstate_virtio_blk = {
1698     .name = "virtio-blk",
1699     .minimum_version_id = 2,
1700     .version_id = 2,
1701     .fields = (VMStateField[]) {
1702         VMSTATE_VIRTIO_DEVICE,
1703         VMSTATE_END_OF_LIST()
1704     },
1705 };
1706 
1707 static Property virtio_blk_properties[] = {
1708     DEFINE_BLOCK_PROPERTIES(VirtIOBlock, conf.conf),
1709     DEFINE_BLOCK_ERROR_PROPERTIES(VirtIOBlock, conf.conf),
1710     DEFINE_BLOCK_CHS_PROPERTIES(VirtIOBlock, conf.conf),
1711     DEFINE_PROP_STRING("serial", VirtIOBlock, conf.serial),
1712     DEFINE_PROP_BIT64("config-wce", VirtIOBlock, host_features,
1713                       VIRTIO_BLK_F_CONFIG_WCE, true),
1714 #ifdef __linux__
1715     DEFINE_PROP_BIT64("scsi", VirtIOBlock, host_features,
1716                       VIRTIO_BLK_F_SCSI, false),
1717 #endif
1718     DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
1719                     true),
1720     DEFINE_PROP_UINT16("num-queues", VirtIOBlock, conf.num_queues,
1721                        VIRTIO_BLK_AUTO_NUM_QUEUES),
1722     DEFINE_PROP_UINT16("queue-size", VirtIOBlock, conf.queue_size, 256),
1723     DEFINE_PROP_BOOL("seg-max-adjust", VirtIOBlock, conf.seg_max_adjust, true),
1724     DEFINE_PROP_LINK("iothread", VirtIOBlock, conf.iothread, TYPE_IOTHREAD,
1725                      IOThread *),
1726     DEFINE_PROP_BIT64("discard", VirtIOBlock, host_features,
1727                       VIRTIO_BLK_F_DISCARD, true),
1728     DEFINE_PROP_BOOL("report-discard-granularity", VirtIOBlock,
1729                      conf.report_discard_granularity, true),
1730     DEFINE_PROP_BIT64("write-zeroes", VirtIOBlock, host_features,
1731                       VIRTIO_BLK_F_WRITE_ZEROES, true),
1732     DEFINE_PROP_UINT32("max-discard-sectors", VirtIOBlock,
1733                        conf.max_discard_sectors, BDRV_REQUEST_MAX_SECTORS),
1734     DEFINE_PROP_UINT32("max-write-zeroes-sectors", VirtIOBlock,
1735                        conf.max_write_zeroes_sectors, BDRV_REQUEST_MAX_SECTORS),
1736     DEFINE_PROP_BOOL("x-enable-wce-if-config-wce", VirtIOBlock,
1737                      conf.x_enable_wce_if_config_wce, true),
1738     DEFINE_PROP_END_OF_LIST(),
1739 };
1740 
1741 static void virtio_blk_class_init(ObjectClass *klass, void *data)
1742 {
1743     DeviceClass *dc = DEVICE_CLASS(klass);
1744     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
1745 
1746     device_class_set_props(dc, virtio_blk_properties);
1747     dc->vmsd = &vmstate_virtio_blk;
1748     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
1749     vdc->realize = virtio_blk_device_realize;
1750     vdc->unrealize = virtio_blk_device_unrealize;
1751     vdc->get_config = virtio_blk_update_config;
1752     vdc->set_config = virtio_blk_set_config;
1753     vdc->get_features = virtio_blk_get_features;
1754     vdc->set_status = virtio_blk_set_status;
1755     vdc->reset = virtio_blk_reset;
1756     vdc->save = virtio_blk_save_device;
1757     vdc->load = virtio_blk_load_device;
1758     vdc->start_ioeventfd = virtio_blk_data_plane_start;
1759     vdc->stop_ioeventfd = virtio_blk_data_plane_stop;
1760 }
1761 
1762 static const TypeInfo virtio_blk_info = {
1763     .name = TYPE_VIRTIO_BLK,
1764     .parent = TYPE_VIRTIO_DEVICE,
1765     .instance_size = sizeof(VirtIOBlock),
1766     .instance_init = virtio_blk_instance_init,
1767     .class_init = virtio_blk_class_init,
1768 };
1769 
1770 static void virtio_register_types(void)
1771 {
1772     type_register_static(&virtio_blk_info);
1773 }
1774 
1775 type_init(virtio_register_types)
1776