xen: Replace some tab-indents with spaces (clean-up).
[qemu.git] / hw / xen_disk.c
1 /*
2 * xen paravirt block device backend
3 *
4 * (c) Gerd Hoffmann <kraxel@redhat.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; under version 2 of the License.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, see <http://www.gnu.org/licenses/>.
17 */
18
19 #include <stdio.h>
20 #include <stdlib.h>
21 #include <stdarg.h>
22 #include <string.h>
23 #include <unistd.h>
24 #include <signal.h>
25 #include <inttypes.h>
26 #include <time.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <sys/ioctl.h>
30 #include <sys/types.h>
31 #include <sys/stat.h>
32 #include <sys/mman.h>
33 #include <sys/uio.h>
34
35 #include <xs.h>
36 #include <xenctrl.h>
37 #include <xen/io/xenbus.h>
38
39 #include "hw.h"
40 #include "block_int.h"
41 #include "qemu-char.h"
42 #include "xen_blkif.h"
43 #include "xen_backend.h"
44 #include "blockdev.h"
45
46 /* ------------------------------------------------------------- */
47
48 static int syncwrite = 0;
49 static int batch_maps = 0;
50
51 static int max_requests = 32;
52 static int use_aio = 1;
53
54 /* ------------------------------------------------------------- */
55
56 #define BLOCK_SIZE 512
57 #define IOCB_COUNT (BLKIF_MAX_SEGMENTS_PER_REQUEST + 2)
58
59 struct ioreq {
60 blkif_request_t req;
61 int16_t status;
62
63 /* parsed request */
64 off_t start;
65 QEMUIOVector v;
66 int presync;
67 int postsync;
68
69 /* grant mapping */
70 uint32_t domids[BLKIF_MAX_SEGMENTS_PER_REQUEST];
71 uint32_t refs[BLKIF_MAX_SEGMENTS_PER_REQUEST];
72 int prot;
73 void *page[BLKIF_MAX_SEGMENTS_PER_REQUEST];
74 void *pages;
75
76 /* aio status */
77 int aio_inflight;
78 int aio_errors;
79
80 struct XenBlkDev *blkdev;
81 QLIST_ENTRY(ioreq) list;
82 };
83
84 struct XenBlkDev {
85 struct XenDevice xendev; /* must be first */
86 char *params;
87 char *mode;
88 char *type;
89 char *dev;
90 char *devtype;
91 const char *fileproto;
92 const char *filename;
93 int ring_ref;
94 void *sring;
95 int64_t file_blk;
96 int64_t file_size;
97 int protocol;
98 blkif_back_rings_t rings;
99 int more_work;
100 int cnt_map;
101
102 /* request lists */
103 QLIST_HEAD(inflight_head, ioreq) inflight;
104 QLIST_HEAD(finished_head, ioreq) finished;
105 QLIST_HEAD(freelist_head, ioreq) freelist;
106 int requests_total;
107 int requests_inflight;
108 int requests_finished;
109
110 /* qemu block driver */
111 DriveInfo *dinfo;
112 BlockDriverState *bs;
113 QEMUBH *bh;
114 };
115
116 /* ------------------------------------------------------------- */
117
118 static struct ioreq *ioreq_start(struct XenBlkDev *blkdev)
119 {
120 struct ioreq *ioreq = NULL;
121
122 if (QLIST_EMPTY(&blkdev->freelist)) {
123 if (blkdev->requests_total >= max_requests) {
124 goto out;
125 }
126 /* allocate new struct */
127 ioreq = qemu_mallocz(sizeof(*ioreq));
128 ioreq->blkdev = blkdev;
129 blkdev->requests_total++;
130 qemu_iovec_init(&ioreq->v, BLKIF_MAX_SEGMENTS_PER_REQUEST);
131 } else {
132 /* get one from freelist */
133 ioreq = QLIST_FIRST(&blkdev->freelist);
134 QLIST_REMOVE(ioreq, list);
135 qemu_iovec_reset(&ioreq->v);
136 }
137 QLIST_INSERT_HEAD(&blkdev->inflight, ioreq, list);
138 blkdev->requests_inflight++;
139
140 out:
141 return ioreq;
142 }
143
144 static void ioreq_finish(struct ioreq *ioreq)
145 {
146 struct XenBlkDev *blkdev = ioreq->blkdev;
147
148 QLIST_REMOVE(ioreq, list);
149 QLIST_INSERT_HEAD(&blkdev->finished, ioreq, list);
150 blkdev->requests_inflight--;
151 blkdev->requests_finished++;
152 }
153
154 static void ioreq_release(struct ioreq *ioreq)
155 {
156 struct XenBlkDev *blkdev = ioreq->blkdev;
157
158 QLIST_REMOVE(ioreq, list);
159 memset(ioreq, 0, sizeof(*ioreq));
160 ioreq->blkdev = blkdev;
161 QLIST_INSERT_HEAD(&blkdev->freelist, ioreq, list);
162 blkdev->requests_finished--;
163 }
164
165 /*
166 * translate request into iovec + start offset
167 * do sanity checks along the way
168 */
169 static int ioreq_parse(struct ioreq *ioreq)
170 {
171 struct XenBlkDev *blkdev = ioreq->blkdev;
172 uintptr_t mem;
173 size_t len;
174 int i;
175
176 xen_be_printf(&blkdev->xendev, 3,
177 "op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n",
178 ioreq->req.operation, ioreq->req.nr_segments,
179 ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number);
180 switch (ioreq->req.operation) {
181 case BLKIF_OP_READ:
182 ioreq->prot = PROT_WRITE; /* to memory */
183 break;
184 case BLKIF_OP_WRITE_BARRIER:
185 if (!ioreq->req.nr_segments) {
186 ioreq->presync = 1;
187 return 0;
188 }
189 if (!syncwrite) {
190 ioreq->presync = ioreq->postsync = 1;
191 }
192 /* fall through */
193 case BLKIF_OP_WRITE:
194 ioreq->prot = PROT_READ; /* from memory */
195 if (syncwrite) {
196 ioreq->postsync = 1;
197 }
198 break;
199 default:
200 xen_be_printf(&blkdev->xendev, 0, "error: unknown operation (%d)\n",
201 ioreq->req.operation);
202 goto err;
203 };
204
205 if (ioreq->req.operation != BLKIF_OP_READ && blkdev->mode[0] != 'w') {
206 xen_be_printf(&blkdev->xendev, 0, "error: write req for ro device\n");
207 goto err;
208 }
209
210 ioreq->start = ioreq->req.sector_number * blkdev->file_blk;
211 for (i = 0; i < ioreq->req.nr_segments; i++) {
212 if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
213 xen_be_printf(&blkdev->xendev, 0, "error: nr_segments too big\n");
214 goto err;
215 }
216 if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
217 xen_be_printf(&blkdev->xendev, 0, "error: first > last sector\n");
218 goto err;
219 }
220 if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
221 xen_be_printf(&blkdev->xendev, 0, "error: page crossing\n");
222 goto err;
223 }
224
225 ioreq->domids[i] = blkdev->xendev.dom;
226 ioreq->refs[i] = ioreq->req.seg[i].gref;
227
228 mem = ioreq->req.seg[i].first_sect * blkdev->file_blk;
229 len = (ioreq->req.seg[i].last_sect - ioreq->req.seg[i].first_sect + 1) * blkdev->file_blk;
230 qemu_iovec_add(&ioreq->v, (void*)mem, len);
231 }
232 if (ioreq->start + ioreq->v.size > blkdev->file_size) {
233 xen_be_printf(&blkdev->xendev, 0, "error: access beyond end of file\n");
234 goto err;
235 }
236 return 0;
237
238 err:
239 ioreq->status = BLKIF_RSP_ERROR;
240 return -1;
241 }
242
243 static void ioreq_unmap(struct ioreq *ioreq)
244 {
245 int gnt = ioreq->blkdev->xendev.gnttabdev;
246 int i;
247
248 if (ioreq->v.niov == 0) {
249 return;
250 }
251 if (batch_maps) {
252 if (!ioreq->pages) {
253 return;
254 }
255 if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0) {
256 xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
257 strerror(errno));
258 }
259 ioreq->blkdev->cnt_map -= ioreq->v.niov;
260 ioreq->pages = NULL;
261 } else {
262 for (i = 0; i < ioreq->v.niov; i++) {
263 if (!ioreq->page[i]) {
264 continue;
265 }
266 if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0) {
267 xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
268 strerror(errno));
269 }
270 ioreq->blkdev->cnt_map--;
271 ioreq->page[i] = NULL;
272 }
273 }
274 }
275
276 static int ioreq_map(struct ioreq *ioreq)
277 {
278 int gnt = ioreq->blkdev->xendev.gnttabdev;
279 int i;
280
281 if (ioreq->v.niov == 0) {
282 return 0;
283 }
284 if (batch_maps) {
285 ioreq->pages = xc_gnttab_map_grant_refs
286 (gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
287 if (ioreq->pages == NULL) {
288 xen_be_printf(&ioreq->blkdev->xendev, 0,
289 "can't map %d grant refs (%s, %d maps)\n",
290 ioreq->v.niov, strerror(errno), ioreq->blkdev->cnt_map);
291 return -1;
292 }
293 for (i = 0; i < ioreq->v.niov; i++) {
294 ioreq->v.iov[i].iov_base = ioreq->pages + i * XC_PAGE_SIZE +
295 (uintptr_t)ioreq->v.iov[i].iov_base;
296 }
297 ioreq->blkdev->cnt_map += ioreq->v.niov;
298 } else {
299 for (i = 0; i < ioreq->v.niov; i++) {
300 ioreq->page[i] = xc_gnttab_map_grant_ref
301 (gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
302 if (ioreq->page[i] == NULL) {
303 xen_be_printf(&ioreq->blkdev->xendev, 0,
304 "can't map grant ref %d (%s, %d maps)\n",
305 ioreq->refs[i], strerror(errno), ioreq->blkdev->cnt_map);
306 ioreq_unmap(ioreq);
307 return -1;
308 }
309 ioreq->v.iov[i].iov_base = ioreq->page[i] + (uintptr_t)ioreq->v.iov[i].iov_base;
310 ioreq->blkdev->cnt_map++;
311 }
312 }
313 return 0;
314 }
315
316 static int ioreq_runio_qemu_sync(struct ioreq *ioreq)
317 {
318 struct XenBlkDev *blkdev = ioreq->blkdev;
319 int i, rc, len = 0;
320 off_t pos;
321
322 if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) {
323 goto err_no_map;
324 }
325 if (ioreq->presync) {
326 bdrv_flush(blkdev->bs);
327 }
328
329 switch (ioreq->req.operation) {
330 case BLKIF_OP_READ:
331 pos = ioreq->start;
332 for (i = 0; i < ioreq->v.niov; i++) {
333 rc = bdrv_read(blkdev->bs, pos / BLOCK_SIZE,
334 ioreq->v.iov[i].iov_base,
335 ioreq->v.iov[i].iov_len / BLOCK_SIZE);
336 if (rc != 0) {
337 xen_be_printf(&blkdev->xendev, 0, "rd I/O error (%p, len %zd)\n",
338 ioreq->v.iov[i].iov_base,
339 ioreq->v.iov[i].iov_len);
340 goto err;
341 }
342 len += ioreq->v.iov[i].iov_len;
343 pos += ioreq->v.iov[i].iov_len;
344 }
345 break;
346 case BLKIF_OP_WRITE:
347 case BLKIF_OP_WRITE_BARRIER:
348 if (!ioreq->req.nr_segments) {
349 break;
350 }
351 pos = ioreq->start;
352 for (i = 0; i < ioreq->v.niov; i++) {
353 rc = bdrv_write(blkdev->bs, pos / BLOCK_SIZE,
354 ioreq->v.iov[i].iov_base,
355 ioreq->v.iov[i].iov_len / BLOCK_SIZE);
356 if (rc != 0) {
357 xen_be_printf(&blkdev->xendev, 0, "wr I/O error (%p, len %zd)\n",
358 ioreq->v.iov[i].iov_base,
359 ioreq->v.iov[i].iov_len);
360 goto err;
361 }
362 len += ioreq->v.iov[i].iov_len;
363 pos += ioreq->v.iov[i].iov_len;
364 }
365 break;
366 default:
367 /* unknown operation (shouldn't happen -- parse catches this) */
368 goto err;
369 }
370
371 if (ioreq->postsync) {
372 bdrv_flush(blkdev->bs);
373 }
374 ioreq->status = BLKIF_RSP_OKAY;
375
376 ioreq_unmap(ioreq);
377 ioreq_finish(ioreq);
378 return 0;
379
380 err:
381 ioreq_unmap(ioreq);
382 err_no_map:
383 ioreq_finish(ioreq);
384 ioreq->status = BLKIF_RSP_ERROR;
385 return -1;
386 }
387
388 static void qemu_aio_complete(void *opaque, int ret)
389 {
390 struct ioreq *ioreq = opaque;
391
392 if (ret != 0) {
393 xen_be_printf(&ioreq->blkdev->xendev, 0, "%s I/O error\n",
394 ioreq->req.operation == BLKIF_OP_READ ? "read" : "write");
395 ioreq->aio_errors++;
396 }
397
398 ioreq->aio_inflight--;
399 if (ioreq->aio_inflight > 0) {
400 return;
401 }
402
403 ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY;
404 ioreq_unmap(ioreq);
405 ioreq_finish(ioreq);
406 qemu_bh_schedule(ioreq->blkdev->bh);
407 }
408
409 static int ioreq_runio_qemu_aio(struct ioreq *ioreq)
410 {
411 struct XenBlkDev *blkdev = ioreq->blkdev;
412
413 if (ioreq->req.nr_segments && ioreq_map(ioreq) == -1) {
414 goto err_no_map;
415 }
416
417 ioreq->aio_inflight++;
418 if (ioreq->presync) {
419 bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
420 }
421
422 switch (ioreq->req.operation) {
423 case BLKIF_OP_READ:
424 ioreq->aio_inflight++;
425 bdrv_aio_readv(blkdev->bs, ioreq->start / BLOCK_SIZE,
426 &ioreq->v, ioreq->v.size / BLOCK_SIZE,
427 qemu_aio_complete, ioreq);
428 break;
429 case BLKIF_OP_WRITE:
430 case BLKIF_OP_WRITE_BARRIER:
431 if (!ioreq->req.nr_segments) {
432 break;
433 }
434 ioreq->aio_inflight++;
435 bdrv_aio_writev(blkdev->bs, ioreq->start / BLOCK_SIZE,
436 &ioreq->v, ioreq->v.size / BLOCK_SIZE,
437 qemu_aio_complete, ioreq);
438 break;
439 default:
440 /* unknown operation (shouldn't happen -- parse catches this) */
441 goto err;
442 }
443
444 if (ioreq->postsync) {
445 bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
446 }
447 qemu_aio_complete(ioreq, 0);
448
449 return 0;
450
451 err:
452 ioreq_unmap(ioreq);
453 err_no_map:
454 ioreq_finish(ioreq);
455 ioreq->status = BLKIF_RSP_ERROR;
456 return -1;
457 }
458
459 static int blk_send_response_one(struct ioreq *ioreq)
460 {
461 struct XenBlkDev *blkdev = ioreq->blkdev;
462 int send_notify = 0;
463 int have_requests = 0;
464 blkif_response_t resp;
465 void *dst;
466
467 resp.id = ioreq->req.id;
468 resp.operation = ioreq->req.operation;
469 resp.status = ioreq->status;
470
471 /* Place on the response ring for the relevant domain. */
472 switch (blkdev->protocol) {
473 case BLKIF_PROTOCOL_NATIVE:
474 dst = RING_GET_RESPONSE(&blkdev->rings.native, blkdev->rings.native.rsp_prod_pvt);
475 break;
476 case BLKIF_PROTOCOL_X86_32:
477 dst = RING_GET_RESPONSE(&blkdev->rings.x86_32_part,
478 blkdev->rings.x86_32_part.rsp_prod_pvt);
479 break;
480 case BLKIF_PROTOCOL_X86_64:
481 dst = RING_GET_RESPONSE(&blkdev->rings.x86_64_part,
482 blkdev->rings.x86_64_part.rsp_prod_pvt);
483 break;
484 default:
485 dst = NULL;
486 }
487 memcpy(dst, &resp, sizeof(resp));
488 blkdev->rings.common.rsp_prod_pvt++;
489
490 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blkdev->rings.common, send_notify);
491 if (blkdev->rings.common.rsp_prod_pvt == blkdev->rings.common.req_cons) {
492 /*
493 * Tail check for pending requests. Allows frontend to avoid
494 * notifications if requests are already in flight (lower
495 * overheads and promotes batching).
496 */
497 RING_FINAL_CHECK_FOR_REQUESTS(&blkdev->rings.common, have_requests);
498 } else if (RING_HAS_UNCONSUMED_REQUESTS(&blkdev->rings.common)) {
499 have_requests = 1;
500 }
501
502 if (have_requests) {
503 blkdev->more_work++;
504 }
505 return send_notify;
506 }
507
508 /* walk finished list, send outstanding responses, free requests */
509 static void blk_send_response_all(struct XenBlkDev *blkdev)
510 {
511 struct ioreq *ioreq;
512 int send_notify = 0;
513
514 while (!QLIST_EMPTY(&blkdev->finished)) {
515 ioreq = QLIST_FIRST(&blkdev->finished);
516 send_notify += blk_send_response_one(ioreq);
517 ioreq_release(ioreq);
518 }
519 if (send_notify) {
520 xen_be_send_notify(&blkdev->xendev);
521 }
522 }
523
524 static int blk_get_request(struct XenBlkDev *blkdev, struct ioreq *ioreq, RING_IDX rc)
525 {
526 switch (blkdev->protocol) {
527 case BLKIF_PROTOCOL_NATIVE:
528 memcpy(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.native, rc),
529 sizeof(ioreq->req));
530 break;
531 case BLKIF_PROTOCOL_X86_32:
532 blkif_get_x86_32_req(&ioreq->req,
533 RING_GET_REQUEST(&blkdev->rings.x86_32_part, rc));
534 break;
535 case BLKIF_PROTOCOL_X86_64:
536 blkif_get_x86_64_req(&ioreq->req,
537 RING_GET_REQUEST(&blkdev->rings.x86_64_part, rc));
538 break;
539 }
540 return 0;
541 }
542
543 static void blk_handle_requests(struct XenBlkDev *blkdev)
544 {
545 RING_IDX rc, rp;
546 struct ioreq *ioreq;
547
548 blkdev->more_work = 0;
549
550 rc = blkdev->rings.common.req_cons;
551 rp = blkdev->rings.common.sring->req_prod;
552 xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
553
554 if (use_aio) {
555 blk_send_response_all(blkdev);
556 }
557 while (rc != rp) {
558 /* pull request from ring */
559 if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc)) {
560 break;
561 }
562 ioreq = ioreq_start(blkdev);
563 if (ioreq == NULL) {
564 blkdev->more_work++;
565 break;
566 }
567 blk_get_request(blkdev, ioreq, rc);
568 blkdev->rings.common.req_cons = ++rc;
569
570 /* parse them */
571 if (ioreq_parse(ioreq) != 0) {
572 if (blk_send_response_one(ioreq)) {
573 xen_be_send_notify(&blkdev->xendev);
574 }
575 ioreq_release(ioreq);
576 continue;
577 }
578
579 if (use_aio) {
580 /* run i/o in aio mode */
581 ioreq_runio_qemu_aio(ioreq);
582 } else {
583 /* run i/o in sync mode */
584 ioreq_runio_qemu_sync(ioreq);
585 }
586 }
587 if (!use_aio) {
588 blk_send_response_all(blkdev);
589 }
590
591 if (blkdev->more_work && blkdev->requests_inflight < max_requests) {
592 qemu_bh_schedule(blkdev->bh);
593 }
594 }
595
596 /* ------------------------------------------------------------- */
597
598 static void blk_bh(void *opaque)
599 {
600 struct XenBlkDev *blkdev = opaque;
601 blk_handle_requests(blkdev);
602 }
603
604 static void blk_alloc(struct XenDevice *xendev)
605 {
606 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
607
608 QLIST_INIT(&blkdev->inflight);
609 QLIST_INIT(&blkdev->finished);
610 QLIST_INIT(&blkdev->freelist);
611 blkdev->bh = qemu_bh_new(blk_bh, blkdev);
612 if (xen_mode != XEN_EMULATE) {
613 batch_maps = 1;
614 }
615 }
616
617 static int blk_init(struct XenDevice *xendev)
618 {
619 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
620 int index, qflags, have_barriers, info = 0;
621 char *h;
622
623 /* read xenstore entries */
624 if (blkdev->params == NULL) {
625 blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
626 h = strchr(blkdev->params, ':');
627 if (h != NULL) {
628 blkdev->fileproto = blkdev->params;
629 blkdev->filename = h+1;
630 *h = 0;
631 } else {
632 blkdev->fileproto = "<unset>";
633 blkdev->filename = blkdev->params;
634 }
635 }
636 if (blkdev->mode == NULL) {
637 blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode");
638 }
639 if (blkdev->type == NULL) {
640 blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type");
641 }
642 if (blkdev->dev == NULL) {
643 blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev");
644 }
645 if (blkdev->devtype == NULL) {
646 blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type");
647 }
648
649 /* do we have all we need? */
650 if (blkdev->params == NULL ||
651 blkdev->mode == NULL ||
652 blkdev->type == NULL ||
653 blkdev->dev == NULL) {
654 return -1;
655 }
656
657 /* read-only ? */
658 if (strcmp(blkdev->mode, "w") == 0) {
659 qflags = BDRV_O_RDWR;
660 } else {
661 qflags = 0;
662 info |= VDISK_READONLY;
663 }
664
665 /* cdrom ? */
666 if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom")) {
667 info |= VDISK_CDROM;
668 }
669
670 /* init qemu block driver */
671 index = (blkdev->xendev.dev - 202 * 256) / 16;
672 blkdev->dinfo = drive_get(IF_XEN, 0, index);
673 if (!blkdev->dinfo) {
674 /* setup via xenbus -> create new block driver instance */
675 xen_be_printf(&blkdev->xendev, 2, "create new bdrv (xenbus setup)\n");
676 blkdev->bs = bdrv_new(blkdev->dev);
677 if (bdrv_open(blkdev->bs, blkdev->filename, qflags,
678 bdrv_find_whitelisted_format(blkdev->fileproto)) != 0) {
679 bdrv_delete(blkdev->bs);
680 return -1;
681 }
682 } else {
683 /* setup via qemu cmdline -> already setup for us */
684 xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n");
685 blkdev->bs = blkdev->dinfo->bdrv;
686 }
687 blkdev->file_blk = BLOCK_SIZE;
688 blkdev->file_size = bdrv_getlength(blkdev->bs);
689 if (blkdev->file_size < 0) {
690 xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n",
691 (int)blkdev->file_size, strerror(-blkdev->file_size),
692 blkdev->bs->drv ? blkdev->bs->drv->format_name : "-");
693 blkdev->file_size = 0;
694 }
695 have_barriers = blkdev->bs->drv && blkdev->bs->drv->bdrv_flush ? 1 : 0;
696
697 xen_be_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\","
698 " size %" PRId64 " (%" PRId64 " MB)\n",
699 blkdev->type, blkdev->fileproto, blkdev->filename,
700 blkdev->file_size, blkdev->file_size >> 20);
701
702 /* fill info */
703 xenstore_write_be_int(&blkdev->xendev, "feature-barrier", have_barriers);
704 xenstore_write_be_int(&blkdev->xendev, "info", info);
705 xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk);
706 xenstore_write_be_int(&blkdev->xendev, "sectors",
707 blkdev->file_size / blkdev->file_blk);
708 return 0;
709 }
710
711 static int blk_connect(struct XenDevice *xendev)
712 {
713 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
714
715 if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1) {
716 return -1;
717 }
718 if (xenstore_read_fe_int(&blkdev->xendev, "event-channel",
719 &blkdev->xendev.remote_port) == -1) {
720 return -1;
721 }
722
723 blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
724 if (blkdev->xendev.protocol) {
725 if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_32) == 0) {
726 blkdev->protocol = BLKIF_PROTOCOL_X86_32;
727 }
728 if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_64) == 0) {
729 blkdev->protocol = BLKIF_PROTOCOL_X86_64;
730 }
731 }
732
733 blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
734 blkdev->xendev.dom,
735 blkdev->ring_ref,
736 PROT_READ | PROT_WRITE);
737 if (!blkdev->sring) {
738 return -1;
739 }
740 blkdev->cnt_map++;
741
742 switch (blkdev->protocol) {
743 case BLKIF_PROTOCOL_NATIVE:
744 {
745 blkif_sring_t *sring_native = blkdev->sring;
746 BACK_RING_INIT(&blkdev->rings.native, sring_native, XC_PAGE_SIZE);
747 break;
748 }
749 case BLKIF_PROTOCOL_X86_32:
750 {
751 blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring;
752
753 BACK_RING_INIT(&blkdev->rings.x86_32_part, sring_x86_32, XC_PAGE_SIZE);
754 break;
755 }
756 case BLKIF_PROTOCOL_X86_64:
757 {
758 blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring;
759
760 BACK_RING_INIT(&blkdev->rings.x86_64_part, sring_x86_64, XC_PAGE_SIZE);
761 break;
762 }
763 }
764
765 xen_be_bind_evtchn(&blkdev->xendev);
766
767 xen_be_printf(&blkdev->xendev, 1, "ok: proto %s, ring-ref %d, "
768 "remote port %d, local port %d\n",
769 blkdev->xendev.protocol, blkdev->ring_ref,
770 blkdev->xendev.remote_port, blkdev->xendev.local_port);
771 return 0;
772 }
773
774 static void blk_disconnect(struct XenDevice *xendev)
775 {
776 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
777
778 if (blkdev->bs) {
779 if (!blkdev->dinfo) {
780 /* close/delete only if we created it ourself */
781 bdrv_close(blkdev->bs);
782 bdrv_delete(blkdev->bs);
783 }
784 blkdev->bs = NULL;
785 }
786 xen_be_unbind_evtchn(&blkdev->xendev);
787
788 if (blkdev->sring) {
789 xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
790 blkdev->cnt_map--;
791 blkdev->sring = NULL;
792 }
793 }
794
795 static int blk_free(struct XenDevice *xendev)
796 {
797 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
798 struct ioreq *ioreq;
799
800 while (!QLIST_EMPTY(&blkdev->freelist)) {
801 ioreq = QLIST_FIRST(&blkdev->freelist);
802 QLIST_REMOVE(ioreq, list);
803 qemu_iovec_destroy(&ioreq->v);
804 qemu_free(ioreq);
805 }
806
807 qemu_free(blkdev->params);
808 qemu_free(blkdev->mode);
809 qemu_free(blkdev->type);
810 qemu_free(blkdev->dev);
811 qemu_free(blkdev->devtype);
812 qemu_bh_delete(blkdev->bh);
813 return 0;
814 }
815
816 static void blk_event(struct XenDevice *xendev)
817 {
818 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
819
820 qemu_bh_schedule(blkdev->bh);
821 }
822
823 struct XenDevOps xen_blkdev_ops = {
824 .size = sizeof(struct XenBlkDev),
825 .flags = DEVOPS_FLAG_NEED_GNTDEV,
826 .alloc = blk_alloc,
827 .init = blk_init,
828 .connect = blk_connect,
829 .disconnect = blk_disconnect,
830 .event = blk_event,
831 .free = blk_free,
832 };