1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2011 NetApp, Inc.
5 * All rights reserved.
6 * Copyright 2020-2021 Joyent, Inc.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29 /*
30 * This file and its contents are supplied under the terms of the
31 * Common Development and Distribution License ("CDDL"), version 1.0.
32 * You may only use this file in accordance with the terms of version
33 * 1.0 of the CDDL.
34 *
35 * A full copy of the text of the CDDL should have accompanied this
36 * source. A copy of the CDDL is also available via the Internet at
37 * http://www.illumos.org/license/CDDL.
38 *
39 * Copyright 2014 Pluribus Networks Inc.
40 */
41
42 #include <sys/cdefs.h>
43
44 #include <sys/param.h>
45 #include <sys/linker_set.h>
46 #include <sys/stat.h>
47 #include <sys/uio.h>
48 #include <sys/ioctl.h>
49 #include <sys/disk.h>
50
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <stdint.h>
56 #include <string.h>
57 #include <strings.h>
58 #include <unistd.h>
59 #include <assert.h>
60 #include <pthread.h>
61 #include <md5.h>
62
63 #include "bhyverun.h"
64 #include "config.h"
65 #include "debug.h"
66 #include "pci_emul.h"
67 #include "virtio.h"
68 #include "block_if.h"
69
70 #define VTBLK_BSIZE 512
71 #define VTBLK_RINGSZ 128
72
73 _Static_assert(VTBLK_RINGSZ <= BLOCKIF_RING_MAX, "Each ring entry must be able to queue a request");
74
75 #define VTBLK_S_OK 0
76 #define VTBLK_S_IOERR 1
77 #define VTBLK_S_UNSUPP 2
78
79 #define VTBLK_BLK_ID_BYTES 20 + 1
80
81 /* Capability bits */
82 #define VTBLK_F_BARRIER (1 << 0) /* Does host support barriers? */
83 #define VTBLK_F_SIZE_MAX (1 << 1) /* Indicates maximum segment size */
84 #define VTBLK_F_SEG_MAX (1 << 2) /* Indicates maximum # of segments */
85 #define VTBLK_F_GEOMETRY (1 << 4) /* Legacy geometry available */
86 #define VTBLK_F_RO (1 << 5) /* Disk is read-only */
87 #define VTBLK_F_BLK_SIZE (1 << 6) /* Block size of disk is available*/
88 #define VTBLK_F_SCSI (1 << 7) /* Supports scsi command passthru */
89 #define VTBLK_F_FLUSH (1 << 9) /* Writeback mode enabled after reset */
90 #define VTBLK_F_WCE (1 << 9) /* Legacy alias for FLUSH */
91 #define VTBLK_F_TOPOLOGY (1 << 10) /* Topology information is available */
92 #define VTBLK_F_CONFIG_WCE (1 << 11) /* Writeback mode available in config */
93 #define VTBLK_F_MQ (1 << 12) /* Multi-Queue */
94 #define VTBLK_F_DISCARD (1 << 13) /* Trim blocks */
95 #define VTBLK_F_WRITE_ZEROES (1 << 14) /* Write zeros */
96
97 /*
98 * Host capabilities
99 */
100 #define VTBLK_S_HOSTCAPS \
101 ( VTBLK_F_SEG_MAX | \
102 VTBLK_F_BLK_SIZE | \
103 VTBLK_F_FLUSH | \
104 VTBLK_F_TOPOLOGY | \
105 VIRTIO_RING_F_INDIRECT_DESC ) /* indirect descriptors */
106
107 /*
108 * The current blockif_delete() interface only allows a single delete
109 * request at a time.
110 */
111 #define VTBLK_MAX_DISCARD_SEG 1
112
113 /*
114 * An arbitrary limit to prevent excessive latency due to large
115 * delete requests.
116 */
117 #define VTBLK_MAX_DISCARD_SECT ((16 << 20) / VTBLK_BSIZE) /* 16 MiB */
118
119 /*
120 * Config space "registers"
121 */
122 struct vtblk_config {
123 uint64_t vbc_capacity;
124 uint32_t vbc_size_max;
125 uint32_t vbc_seg_max;
126 struct {
127 uint16_t cylinders;
128 uint8_t heads;
129 uint8_t sectors;
130 } vbc_geometry;
131 uint32_t vbc_blk_size;
132 struct {
133 uint8_t physical_block_exp;
134 uint8_t alignment_offset;
135 uint16_t min_io_size;
136 uint32_t opt_io_size;
137 } vbc_topology;
138 uint8_t vbc_writeback;
139 uint8_t unused0[1];
140 uint16_t num_queues;
141 uint32_t max_discard_sectors;
142 uint32_t max_discard_seg;
143 uint32_t discard_sector_alignment;
144 uint32_t max_write_zeroes_sectors;
145 uint32_t max_write_zeroes_seg;
146 uint8_t write_zeroes_may_unmap;
147 uint8_t unused1[3];
148 } __packed;
149
150 /*
151 * Fixed-size block header
152 */
153 struct virtio_blk_hdr {
154 #define VBH_OP_READ 0
155 #define VBH_OP_WRITE 1
156 #define VBH_OP_SCSI_CMD 2
157 #define VBH_OP_SCSI_CMD_OUT 3
158 #define VBH_OP_FLUSH 4
159 #define VBH_OP_FLUSH_OUT 5
160 #define VBH_OP_IDENT 8
161 #define VBH_OP_DISCARD 11
162 #define VBH_OP_WRITE_ZEROES 13
163
164 #define VBH_FLAG_BARRIER 0x80000000 /* OR'ed into vbh_type */
165 uint32_t vbh_type;
166 uint32_t vbh_ioprio;
167 uint64_t vbh_sector;
168 } __packed;
169
170 /*
171 * Debug printf
172 */
173 static int pci_vtblk_debug;
174 #define DPRINTF(params) if (pci_vtblk_debug) PRINTLN params
175 #define WPRINTF(params) PRINTLN params
176
177 struct pci_vtblk_ioreq {
178 struct blockif_req io_req;
179 struct pci_vtblk_softc *io_sc;
180 uint8_t *io_status;
181 uint16_t io_idx;
182 };
183
184 struct virtio_blk_discard_write_zeroes {
185 uint64_t sector;
186 uint32_t num_sectors;
187 struct {
188 uint32_t unmap:1;
189 uint32_t reserved:31;
190 } flags;
191 };
192
193 /*
194 * Per-device softc
195 */
196 struct pci_vtblk_softc {
197 struct virtio_softc vbsc_vs;
198 pthread_mutex_t vsc_mtx;
199 struct vqueue_info vbsc_vq;
200 struct vtblk_config vbsc_cfg;
201 struct virtio_consts vbsc_consts;
202 struct blockif_ctxt *bc;
203 #ifndef __FreeBSD__
204 int vbsc_wce;
205 #endif
206 char vbsc_ident[VTBLK_BLK_ID_BYTES];
207 struct pci_vtblk_ioreq vbsc_ios[VTBLK_RINGSZ];
208 };
209
210 static void pci_vtblk_reset(void *);
211 static void pci_vtblk_notify(void *, struct vqueue_info *);
212 static int pci_vtblk_cfgread(void *, int, int, uint32_t *);
213 static int pci_vtblk_cfgwrite(void *, int, int, uint32_t);
214 #ifndef __FreeBSD__
215 static void pci_vtblk_apply_feats(void *, uint64_t);
216 #endif
217
218 static struct virtio_consts vtblk_vi_consts = {
219 .vc_name = "vtblk",
220 .vc_nvq = 1,
221 .vc_cfgsize = sizeof(struct vtblk_config),
222 .vc_reset = pci_vtblk_reset,
223 .vc_qnotify = pci_vtblk_notify,
224 .vc_cfgread = pci_vtblk_cfgread,
225 .vc_cfgwrite = pci_vtblk_cfgwrite,
226 #ifndef __FreeBSD__
227 .vc_apply_features = pci_vtblk_apply_feats,
228 #else
229 .vc_apply_features = NULL,
230 #endif
231 .vc_hv_caps = VTBLK_S_HOSTCAPS,
232 };
233
234 static void
pci_vtblk_reset(void * vsc)235 pci_vtblk_reset(void *vsc)
236 {
237 struct pci_vtblk_softc *sc = vsc;
238
239 DPRINTF(("vtblk: device reset requested !"));
240 vi_reset_dev(&sc->vbsc_vs);
241 #ifndef __FreeBSD__
242 /* Disable write cache until FLUSH feature is negotiated */
243 (void) blockif_set_wce(sc->bc, 0);
244 sc->vbsc_wce = 0;
245 #endif
246 }
247
248 static void
pci_vtblk_done_locked(struct pci_vtblk_ioreq * io,int err)249 pci_vtblk_done_locked(struct pci_vtblk_ioreq *io, int err)
250 {
251 struct pci_vtblk_softc *sc = io->io_sc;
252
253 /* convert errno into a virtio block error return */
254 if (err == EOPNOTSUPP || err == ENOSYS)
255 *io->io_status = VTBLK_S_UNSUPP;
256 else if (err != 0)
257 *io->io_status = VTBLK_S_IOERR;
258 else
259 *io->io_status = VTBLK_S_OK;
260
261 /*
262 * Return the descriptor back to the host.
263 * We wrote 1 byte (our status) to host.
264 */
265 vq_relchain(&sc->vbsc_vq, io->io_idx, 1);
266 vq_endchains(&sc->vbsc_vq, 0);
267 }
268
269 static void
pci_vtblk_done(struct blockif_req * br,int err)270 pci_vtblk_done(struct blockif_req *br, int err)
271 {
272 struct pci_vtblk_ioreq *io = br->br_param;
273 struct pci_vtblk_softc *sc = io->io_sc;
274
275 pthread_mutex_lock(&sc->vsc_mtx);
276 pci_vtblk_done_locked(io, err);
277 pthread_mutex_unlock(&sc->vsc_mtx);
278 }
279
280 static void
pci_vtblk_proc(struct pci_vtblk_softc * sc,struct vqueue_info * vq)281 pci_vtblk_proc(struct pci_vtblk_softc *sc, struct vqueue_info *vq)
282 {
283 struct virtio_blk_hdr *vbh;
284 struct pci_vtblk_ioreq *io;
285 int i, n;
286 int err;
287 ssize_t iolen;
288 int writeop, type;
289 struct vi_req req;
290 struct iovec iov[BLOCKIF_IOV_MAX + 2];
291 struct virtio_blk_discard_write_zeroes *discard;
292
293 n = vq_getchain(vq, iov, BLOCKIF_IOV_MAX + 2, &req);
294
295 /*
296 * The first descriptor will be the read-only fixed header,
297 * and the last is for status (hence +2 above and below).
298 * The remaining iov's are the actual data I/O vectors.
299 *
300 * XXX - note - this fails on crash dump, which does a
301 * VIRTIO_BLK_T_FLUSH with a zero transfer length
302 */
303 assert(n >= 2 && n <= BLOCKIF_IOV_MAX + 2);
304
305 io = &sc->vbsc_ios[req.idx];
306 assert(req.readable != 0);
307 assert(iov[0].iov_len == sizeof(struct virtio_blk_hdr));
308 vbh = (struct virtio_blk_hdr *)iov[0].iov_base;
309 memcpy(&io->io_req.br_iov, &iov[1], sizeof(struct iovec) * (n - 2));
310 io->io_req.br_iovcnt = n - 2;
311 io->io_req.br_offset = vbh->vbh_sector * VTBLK_BSIZE;
312 io->io_status = (uint8_t *)iov[--n].iov_base;
313 assert(req.writable != 0);
314 assert(iov[n].iov_len == 1);
315
316 /*
317 * XXX
318 * The guest should not be setting the BARRIER flag because
319 * we don't advertise the capability.
320 */
321 type = vbh->vbh_type & ~VBH_FLAG_BARRIER;
322 writeop = (type == VBH_OP_WRITE || type == VBH_OP_DISCARD);
323 /*
324 * - Write op implies read-only descriptor
325 * - Read/ident op implies write-only descriptor
326 *
327 * By taking away either the read-only fixed header or the write-only
328 * status iovec, the following condition should hold true.
329 */
330 assert(n == (writeop ? req.readable : req.writable));
331
332 iolen = 0;
333 for (i = 1; i < n; i++) {
334 iolen += iov[i].iov_len;
335 }
336 io->io_req.br_resid = iolen;
337
338 DPRINTF(("virtio-block: %s op, %zd bytes, %d segs, offset %ld",
339 writeop ? "write/discard" : "read/ident", iolen, i - 1,
340 io->io_req.br_offset));
341
342 switch (type) {
343 case VBH_OP_READ:
344 err = blockif_read(sc->bc, &io->io_req);
345 break;
346 case VBH_OP_WRITE:
347 err = blockif_write(sc->bc, &io->io_req);
348 break;
349 case VBH_OP_DISCARD:
350 /*
351 * We currently only support a single request, if the guest
352 * has submitted a request that doesn't conform to the
353 * requirements, we return a error.
354 */
355 if (iov[1].iov_len != sizeof (*discard)) {
356 pci_vtblk_done_locked(io, EINVAL);
357 return;
358 }
359
360 /* The segments to discard are provided rather than data */
361 discard = (struct virtio_blk_discard_write_zeroes *)
362 iov[1].iov_base;
363
364 /*
365 * virtio v1.1 5.2.6.2:
366 * The device MUST set the status byte to VIRTIO_BLK_S_UNSUPP
367 * for discard and write zeroes commands if any unknown flag is
368 * set. Furthermore, the device MUST set the status byte to
369 * VIRTIO_BLK_S_UNSUPP for discard commands if the unmap flag
370 * is set.
371 *
372 * Currently there are no known flags for a DISCARD request.
373 */
374 if (discard->flags.unmap != 0 || discard->flags.reserved != 0) {
375 pci_vtblk_done_locked(io, ENOTSUP);
376 return;
377 }
378
379 /* Make sure the request doesn't exceed our size limit */
380 if (discard->num_sectors > VTBLK_MAX_DISCARD_SECT) {
381 pci_vtblk_done_locked(io, EINVAL);
382 return;
383 }
384
385 io->io_req.br_offset = discard->sector * VTBLK_BSIZE;
386 io->io_req.br_resid = discard->num_sectors * VTBLK_BSIZE;
387 err = blockif_delete(sc->bc, &io->io_req);
388 break;
389 case VBH_OP_FLUSH:
390 case VBH_OP_FLUSH_OUT:
391 err = blockif_flush(sc->bc, &io->io_req);
392 break;
393 case VBH_OP_IDENT:
394 /* Assume a single buffer */
395 /* S/n equal to buffer is not zero-terminated. */
396 memset(iov[1].iov_base, 0, iov[1].iov_len);
397 strncpy(iov[1].iov_base, sc->vbsc_ident,
398 MIN(iov[1].iov_len, sizeof(sc->vbsc_ident)));
399 pci_vtblk_done_locked(io, 0);
400 return;
401 default:
402 pci_vtblk_done_locked(io, EOPNOTSUPP);
403 return;
404 }
405 assert(err == 0);
406 }
407
408 static void
pci_vtblk_notify(void * vsc,struct vqueue_info * vq)409 pci_vtblk_notify(void *vsc, struct vqueue_info *vq)
410 {
411 struct pci_vtblk_softc *sc = vsc;
412
413 while (vq_has_descs(vq))
414 pci_vtblk_proc(sc, vq);
415 }
416
417 static void
pci_vtblk_resized(struct blockif_ctxt * bctxt __unused,void * arg,size_t new_size)418 pci_vtblk_resized(struct blockif_ctxt *bctxt __unused, void *arg,
419 size_t new_size)
420 {
421 struct pci_vtblk_softc *sc;
422
423 sc = arg;
424
425 sc->vbsc_cfg.vbc_capacity = new_size / VTBLK_BSIZE; /* 512-byte units */
426 vi_interrupt(&sc->vbsc_vs, VIRTIO_PCI_ISR_CONFIG,
427 sc->vbsc_vs.vs_msix_cfg_idx);
428 }
429
430 static int
pci_vtblk_init(struct pci_devinst * pi,nvlist_t * nvl)431 pci_vtblk_init(struct pci_devinst *pi, nvlist_t *nvl)
432 {
433 char bident[sizeof("XXX:XXX")];
434 struct blockif_ctxt *bctxt;
435 const char *path, *serial;
436 MD5_CTX mdctx;
437 u_char digest[16];
438 struct pci_vtblk_softc *sc;
439 off_t size;
440 int i, sectsz, sts, sto;
441
442 /*
443 * The supplied backing file has to exist
444 */
445 snprintf(bident, sizeof(bident), "%u:%u", pi->pi_slot, pi->pi_func);
446 bctxt = blockif_open(nvl, bident);
447 if (bctxt == NULL) {
448 perror("Could not open backing file");
449 return (1);
450 }
451
452 if (blockif_add_boot_device(pi, bctxt)) {
453 perror("Invalid boot device");
454 return (1);
455 }
456
457 size = blockif_size(bctxt);
458 sectsz = blockif_sectsz(bctxt);
459 blockif_psectsz(bctxt, &sts, &sto);
460
461 sc = calloc(1, sizeof(struct pci_vtblk_softc));
462 sc->bc = bctxt;
463 for (i = 0; i < VTBLK_RINGSZ; i++) {
464 struct pci_vtblk_ioreq *io = &sc->vbsc_ios[i];
465 io->io_req.br_callback = pci_vtblk_done;
466 io->io_req.br_param = io;
467 io->io_sc = sc;
468 io->io_idx = i;
469 }
470
471 bcopy(&vtblk_vi_consts, &sc->vbsc_consts, sizeof (vtblk_vi_consts));
472 if (blockif_candelete(sc->bc))
473 sc->vbsc_consts.vc_hv_caps |= VTBLK_F_DISCARD;
474
475 #ifndef __FreeBSD__
476 /* Disable write cache until FLUSH feature is negotiated */
477 (void) blockif_set_wce(sc->bc, 0);
478 sc->vbsc_wce = 0;
479 #endif
480
481 pthread_mutex_init(&sc->vsc_mtx, NULL);
482
483 /* init virtio softc and virtqueues */
484 vi_softc_linkup(&sc->vbsc_vs, &sc->vbsc_consts, sc, pi, &sc->vbsc_vq);
485 sc->vbsc_vs.vs_mtx = &sc->vsc_mtx;
486
487 sc->vbsc_vq.vq_qsize = VTBLK_RINGSZ;
488 /* sc->vbsc_vq.vq_notify = we have no per-queue notify */
489
490 /*
491 * If an explicit identifier is not given, create an
492 * identifier using parts of the md5 sum of the filename.
493 */
494 bzero(sc->vbsc_ident, VTBLK_BLK_ID_BYTES);
495 if ((serial = get_config_value_node(nvl, "serial")) != NULL ||
496 (serial = get_config_value_node(nvl, "ser")) != NULL) {
497 strlcpy(sc->vbsc_ident, serial, VTBLK_BLK_ID_BYTES);
498 } else {
499 path = get_config_value_node(nvl, "path");
500 MD5Init(&mdctx);
501 MD5Update(&mdctx, path, strlen(path));
502 MD5Final(digest, &mdctx);
503 snprintf(sc->vbsc_ident, VTBLK_BLK_ID_BYTES,
504 "BHYVE-%02X%02X-%02X%02X-%02X%02X",
505 digest[0], digest[1], digest[2], digest[3], digest[4],
506 digest[5]);
507 }
508
509 /* setup virtio block config space */
510 sc->vbsc_cfg.vbc_capacity = size / VTBLK_BSIZE; /* 512-byte units */
511 sc->vbsc_cfg.vbc_size_max = 0; /* not negotiated */
512
513 /*
514 * If Linux is presented with a seg_max greater than the virtio queue
515 * size, it can stumble into situations where it violates its own
516 * invariants and panics. For safety, we keep seg_max clamped, paying
517 * heed to the two extra descriptors needed for the header and status
518 * of a request.
519 */
520 sc->vbsc_cfg.vbc_seg_max = MIN(VTBLK_RINGSZ - 2, BLOCKIF_IOV_MAX);
521 sc->vbsc_cfg.vbc_geometry.cylinders = 0; /* no geometry */
522 sc->vbsc_cfg.vbc_geometry.heads = 0;
523 sc->vbsc_cfg.vbc_geometry.sectors = 0;
524 sc->vbsc_cfg.vbc_blk_size = sectsz;
525 sc->vbsc_cfg.vbc_topology.physical_block_exp =
526 (sts > sectsz) ? (ffsll(sts / sectsz) - 1) : 0;
527 sc->vbsc_cfg.vbc_topology.alignment_offset =
528 (sto != 0) ? ((sts - sto) / sectsz) : 0;
529 sc->vbsc_cfg.vbc_topology.min_io_size = 0;
530 sc->vbsc_cfg.vbc_topology.opt_io_size = 0;
531 sc->vbsc_cfg.vbc_writeback = 0;
532 sc->vbsc_cfg.max_discard_sectors = VTBLK_MAX_DISCARD_SECT;
533 sc->vbsc_cfg.max_discard_seg = VTBLK_MAX_DISCARD_SEG;
534 sc->vbsc_cfg.discard_sector_alignment = MAX(sectsz, sts) / VTBLK_BSIZE;
535
536 /*
537 * Should we move some of this into virtio.c? Could
538 * have the device, class, and subdev_0 as fields in
539 * the virtio constants structure.
540 */
541 pci_set_cfgdata16(pi, PCIR_DEVICE, VIRTIO_DEV_BLOCK);
542 pci_set_cfgdata16(pi, PCIR_VENDOR, VIRTIO_VENDOR);
543 pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_STORAGE);
544 pci_set_cfgdata16(pi, PCIR_SUBDEV_0, VIRTIO_ID_BLOCK);
545 pci_set_cfgdata16(pi, PCIR_SUBVEND_0, VIRTIO_VENDOR);
546
547 if (vi_intr_init(&sc->vbsc_vs, 1, fbsdrun_virtio_msix())) {
548 blockif_close(sc->bc);
549 free(sc);
550 return (1);
551 }
552 vi_set_io_bar(&sc->vbsc_vs, 0);
553 blockif_register_resize_callback(sc->bc, pci_vtblk_resized, sc);
554 return (0);
555 }
556
557 static int
pci_vtblk_cfgwrite(void * vsc __unused,int offset,int size __unused,uint32_t value __unused)558 pci_vtblk_cfgwrite(void *vsc __unused, int offset, int size __unused,
559 uint32_t value __unused)
560 {
561
562 DPRINTF(("vtblk: write to readonly reg %d", offset));
563 return (1);
564 }
565
566 static int
pci_vtblk_cfgread(void * vsc,int offset,int size,uint32_t * retval)567 pci_vtblk_cfgread(void *vsc, int offset, int size, uint32_t *retval)
568 {
569 struct pci_vtblk_softc *sc = vsc;
570 void *ptr;
571
572 /* our caller has already verified offset and size */
573 ptr = (uint8_t *)&sc->vbsc_cfg + offset;
574 memcpy(retval, ptr, size);
575 return (0);
576 }
577
578 #ifndef __FreeBSD__
579 void
pci_vtblk_apply_feats(void * vsc,uint64_t caps)580 pci_vtblk_apply_feats(void *vsc, uint64_t caps)
581 {
582 struct pci_vtblk_softc *sc = vsc;
583 const int wce_next = ((caps & VTBLK_F_FLUSH) != 0) ? 1 : 0;
584
585 if (sc->vbsc_wce != wce_next) {
586 (void) blockif_set_wce(sc->bc, wce_next);
587 sc->vbsc_wce = wce_next;
588 }
589 }
590 #endif /* __FreeBSD__ */
591
592 static const struct pci_devemu pci_de_vblk = {
593 .pe_emu = "virtio-blk",
594 .pe_init = pci_vtblk_init,
595 .pe_legacy_config = blockif_legacy_config,
596 .pe_barwrite = vi_pci_write,
597 .pe_barread = vi_pci_read,
598 };
599 PCI_EMUL_SET(pci_de_vblk);
600