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pci: Remove pci_enable_capability_support()
[qemu-kvm/stefanha.git] / hw / xen_disk.c
blob134ac3388e9ecd0174f2bfb7ca6ef74a53cd015c
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 /* allocate new struct */
126 ioreq = qemu_mallocz(sizeof(*ioreq));
127 ioreq->blkdev = blkdev;
128 blkdev->requests_total++;
129 qemu_iovec_init(&ioreq->v, BLKIF_MAX_SEGMENTS_PER_REQUEST);
130 } else {
131 /* get one from freelist */
132 ioreq = QLIST_FIRST(&blkdev->freelist);
133 QLIST_REMOVE(ioreq, list);
134 qemu_iovec_reset(&ioreq->v);
135 }
136 QLIST_INSERT_HEAD(&blkdev->inflight, ioreq, list);
137 blkdev->requests_inflight++;
138
139 out:
140 return ioreq;
141 }
142
143 static void ioreq_finish(struct ioreq *ioreq)
144 {
145 struct XenBlkDev *blkdev = ioreq->blkdev;
146
147 QLIST_REMOVE(ioreq, list);
148 QLIST_INSERT_HEAD(&blkdev->finished, ioreq, list);
149 blkdev->requests_inflight--;
150 blkdev->requests_finished++;
151 }
152
153 static void ioreq_release(struct ioreq *ioreq)
154 {
155 struct XenBlkDev *blkdev = ioreq->blkdev;
156
157 QLIST_REMOVE(ioreq, list);
158 memset(ioreq, 0, sizeof(*ioreq));
159 ioreq->blkdev = blkdev;
160 QLIST_INSERT_HEAD(&blkdev->freelist, ioreq, list);
161 blkdev->requests_finished--;
162 }
163
164 /*
165 * translate request into iovec + start offset
166 * do sanity checks along the way
167 */
168 static int ioreq_parse(struct ioreq *ioreq)
169 {
170 struct XenBlkDev *blkdev = ioreq->blkdev;
171 uintptr_t mem;
172 size_t len;
173 int i;
174
175 xen_be_printf(&blkdev->xendev, 3,
176 "op %d, nr %d, handle %d, id %" PRId64 ", sector %" PRId64 "\n",
177 ioreq->req.operation, ioreq->req.nr_segments,
178 ioreq->req.handle, ioreq->req.id, ioreq->req.sector_number);
179 switch (ioreq->req.operation) {
180 case BLKIF_OP_READ:
181 ioreq->prot = PROT_WRITE; /* to memory */
182 break;
183 case BLKIF_OP_WRITE_BARRIER:
184 if (!syncwrite)
185 ioreq->presync = ioreq->postsync = 1;
186 /* fall through */
187 case BLKIF_OP_WRITE:
188 ioreq->prot = PROT_READ; /* from memory */
189 if (syncwrite)
190 ioreq->postsync = 1;
191 break;
192 default:
193 xen_be_printf(&blkdev->xendev, 0, "error: unknown operation (%d)\n",
194 ioreq->req.operation);
195 goto err;
196 };
197
198 if (ioreq->req.operation != BLKIF_OP_READ && blkdev->mode[0] != 'w') {
199 xen_be_printf(&blkdev->xendev, 0, "error: write req for ro device\n");
200 goto err;
201 }
202
203 ioreq->start = ioreq->req.sector_number * blkdev->file_blk;
204 for (i = 0; i < ioreq->req.nr_segments; i++) {
205 if (i == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
206 xen_be_printf(&blkdev->xendev, 0, "error: nr_segments too big\n");
207 goto err;
208 }
209 if (ioreq->req.seg[i].first_sect > ioreq->req.seg[i].last_sect) {
210 xen_be_printf(&blkdev->xendev, 0, "error: first > last sector\n");
211 goto err;
212 }
213 if (ioreq->req.seg[i].last_sect * BLOCK_SIZE >= XC_PAGE_SIZE) {
214 xen_be_printf(&blkdev->xendev, 0, "error: page crossing\n");
215 goto err;
216 }
217
218 ioreq->domids[i] = blkdev->xendev.dom;
219 ioreq->refs[i] = ioreq->req.seg[i].gref;
220
221 mem = ioreq->req.seg[i].first_sect * blkdev->file_blk;
222 len = (ioreq->req.seg[i].last_sect - ioreq->req.seg[i].first_sect + 1) * blkdev->file_blk;
223 qemu_iovec_add(&ioreq->v, (void*)mem, len);
224 }
225 if (ioreq->start + ioreq->v.size > blkdev->file_size) {
226 xen_be_printf(&blkdev->xendev, 0, "error: access beyond end of file\n");
227 goto err;
228 }
229 return 0;
230
231 err:
232 ioreq->status = BLKIF_RSP_ERROR;
233 return -1;
234 }
235
236 static void ioreq_unmap(struct ioreq *ioreq)
237 {
238 int gnt = ioreq->blkdev->xendev.gnttabdev;
239 int i;
240
241 if (ioreq->v.niov == 0)
242 return;
243 if (batch_maps) {
244 if (!ioreq->pages)
245 return;
246 if (xc_gnttab_munmap(gnt, ioreq->pages, ioreq->v.niov) != 0)
247 xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
248 strerror(errno));
249 ioreq->blkdev->cnt_map -= ioreq->v.niov;
250 ioreq->pages = NULL;
251 } else {
252 for (i = 0; i < ioreq->v.niov; i++) {
253 if (!ioreq->page[i])
254 continue;
255 if (xc_gnttab_munmap(gnt, ioreq->page[i], 1) != 0)
256 xen_be_printf(&ioreq->blkdev->xendev, 0, "xc_gnttab_munmap failed: %s\n",
257 strerror(errno));
258 ioreq->blkdev->cnt_map--;
259 ioreq->page[i] = NULL;
260 }
261 }
262 }
263
264 static int ioreq_map(struct ioreq *ioreq)
265 {
266 int gnt = ioreq->blkdev->xendev.gnttabdev;
267 int i;
268
269 if (ioreq->v.niov == 0)
270 return 0;
271 if (batch_maps) {
272 ioreq->pages = xc_gnttab_map_grant_refs
273 (gnt, ioreq->v.niov, ioreq->domids, ioreq->refs, ioreq->prot);
274 if (ioreq->pages == NULL) {
275 xen_be_printf(&ioreq->blkdev->xendev, 0,
276 "can't map %d grant refs (%s, %d maps)\n",
277 ioreq->v.niov, strerror(errno), ioreq->blkdev->cnt_map);
278 return -1;
279 }
280 for (i = 0; i < ioreq->v.niov; i++)
281 ioreq->v.iov[i].iov_base = ioreq->pages + i * XC_PAGE_SIZE +
282 (uintptr_t)ioreq->v.iov[i].iov_base;
283 ioreq->blkdev->cnt_map += ioreq->v.niov;
284 } else {
285 for (i = 0; i < ioreq->v.niov; i++) {
286 ioreq->page[i] = xc_gnttab_map_grant_ref
287 (gnt, ioreq->domids[i], ioreq->refs[i], ioreq->prot);
288 if (ioreq->page[i] == NULL) {
289 xen_be_printf(&ioreq->blkdev->xendev, 0,
290 "can't map grant ref %d (%s, %d maps)\n",
291 ioreq->refs[i], strerror(errno), ioreq->blkdev->cnt_map);
292 ioreq_unmap(ioreq);
293 return -1;
294 }
295 ioreq->v.iov[i].iov_base = ioreq->page[i] + (uintptr_t)ioreq->v.iov[i].iov_base;
296 ioreq->blkdev->cnt_map++;
297 }
298 }
299 return 0;
300 }
301
302 static int ioreq_runio_qemu_sync(struct ioreq *ioreq)
303 {
304 struct XenBlkDev *blkdev = ioreq->blkdev;
305 int i, rc, len = 0;
306 off_t pos;
307
308 if (ioreq_map(ioreq) == -1)
309 goto err;
310 if (ioreq->presync)
311 bdrv_flush(blkdev->bs);
312
313 switch (ioreq->req.operation) {
314 case BLKIF_OP_READ:
315 pos = ioreq->start;
316 for (i = 0; i < ioreq->v.niov; i++) {
317 rc = bdrv_read(blkdev->bs, pos / BLOCK_SIZE,
318 ioreq->v.iov[i].iov_base,
319 ioreq->v.iov[i].iov_len / BLOCK_SIZE);
320 if (rc != 0) {
321 xen_be_printf(&blkdev->xendev, 0, "rd I/O error (%p, len %zd)\n",
322 ioreq->v.iov[i].iov_base,
323 ioreq->v.iov[i].iov_len);
324 goto err;
325 }
326 len += ioreq->v.iov[i].iov_len;
327 pos += ioreq->v.iov[i].iov_len;
328 }
329 break;
330 case BLKIF_OP_WRITE:
331 case BLKIF_OP_WRITE_BARRIER:
332 pos = ioreq->start;
333 for (i = 0; i < ioreq->v.niov; i++) {
334 rc = bdrv_write(blkdev->bs, pos / BLOCK_SIZE,
335 ioreq->v.iov[i].iov_base,
336 ioreq->v.iov[i].iov_len / BLOCK_SIZE);
337 if (rc != 0) {
338 xen_be_printf(&blkdev->xendev, 0, "wr I/O error (%p, len %zd)\n",
339 ioreq->v.iov[i].iov_base,
340 ioreq->v.iov[i].iov_len);
341 goto err;
342 }
343 len += ioreq->v.iov[i].iov_len;
344 pos += ioreq->v.iov[i].iov_len;
345 }
346 break;
347 default:
348 /* unknown operation (shouldn't happen -- parse catches this) */
349 goto err;
350 }
351
352 if (ioreq->postsync)
353 bdrv_flush(blkdev->bs);
354 ioreq->status = BLKIF_RSP_OKAY;
355
356 ioreq_unmap(ioreq);
357 ioreq_finish(ioreq);
358 return 0;
359
360 err:
361 ioreq->status = BLKIF_RSP_ERROR;
362 return -1;
363 }
364
365 static void qemu_aio_complete(void *opaque, int ret)
366 {
367 struct ioreq *ioreq = opaque;
368
369 if (ret != 0) {
370 xen_be_printf(&ioreq->blkdev->xendev, 0, "%s I/O error\n",
371 ioreq->req.operation == BLKIF_OP_READ ? "read" : "write");
372 ioreq->aio_errors++;
373 }
374
375 ioreq->aio_inflight--;
376 if (ioreq->aio_inflight > 0)
377 return;
378
379 ioreq->status = ioreq->aio_errors ? BLKIF_RSP_ERROR : BLKIF_RSP_OKAY;
380 ioreq_unmap(ioreq);
381 ioreq_finish(ioreq);
382 qemu_bh_schedule(ioreq->blkdev->bh);
383 }
384
385 static int ioreq_runio_qemu_aio(struct ioreq *ioreq)
386 {
387 struct XenBlkDev *blkdev = ioreq->blkdev;
388
389 if (ioreq_map(ioreq) == -1)
390 goto err;
391
392 ioreq->aio_inflight++;
393 if (ioreq->presync)
394 bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
395
396 switch (ioreq->req.operation) {
397 case BLKIF_OP_READ:
398 ioreq->aio_inflight++;
399 bdrv_aio_readv(blkdev->bs, ioreq->start / BLOCK_SIZE,
400 &ioreq->v, ioreq->v.size / BLOCK_SIZE,
401 qemu_aio_complete, ioreq);
402 break;
403 case BLKIF_OP_WRITE:
404 case BLKIF_OP_WRITE_BARRIER:
405 ioreq->aio_inflight++;
406 bdrv_aio_writev(blkdev->bs, ioreq->start / BLOCK_SIZE,
407 &ioreq->v, ioreq->v.size / BLOCK_SIZE,
408 qemu_aio_complete, ioreq);
409 break;
410 default:
411 /* unknown operation (shouldn't happen -- parse catches this) */
412 goto err;
413 }
414
415 if (ioreq->postsync)
416 bdrv_flush(blkdev->bs); /* FIXME: aio_flush() ??? */
417 qemu_aio_complete(ioreq, 0);
418
419 return 0;
420
421 err:
422 ioreq->status = BLKIF_RSP_ERROR;
423 return -1;
424 }
425
426 static int blk_send_response_one(struct ioreq *ioreq)
427 {
428 struct XenBlkDev *blkdev = ioreq->blkdev;
429 int send_notify = 0;
430 int have_requests = 0;
431 blkif_response_t resp;
432 void *dst;
433
434 resp.id = ioreq->req.id;
435 resp.operation = ioreq->req.operation;
436 resp.status = ioreq->status;
437
438 /* Place on the response ring for the relevant domain. */
439 switch (blkdev->protocol) {
440 case BLKIF_PROTOCOL_NATIVE:
441 dst = RING_GET_RESPONSE(&blkdev->rings.native, blkdev->rings.native.rsp_prod_pvt);
442 break;
443 case BLKIF_PROTOCOL_X86_32:
444 dst = RING_GET_RESPONSE(&blkdev->rings.x86_32_part,
445 blkdev->rings.x86_32_part.rsp_prod_pvt);
446 break;
447 case BLKIF_PROTOCOL_X86_64:
448 dst = RING_GET_RESPONSE(&blkdev->rings.x86_64_part,
449 blkdev->rings.x86_64_part.rsp_prod_pvt);
450 break;
451 default:
452 dst = NULL;
453 }
454 memcpy(dst, &resp, sizeof(resp));
455 blkdev->rings.common.rsp_prod_pvt++;
456
457 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&blkdev->rings.common, send_notify);
458 if (blkdev->rings.common.rsp_prod_pvt == blkdev->rings.common.req_cons) {
459 /*
460 * Tail check for pending requests. Allows frontend to avoid
461 * notifications if requests are already in flight (lower
462 * overheads and promotes batching).
463 */
464 RING_FINAL_CHECK_FOR_REQUESTS(&blkdev->rings.common, have_requests);
465 } else if (RING_HAS_UNCONSUMED_REQUESTS(&blkdev->rings.common)) {
466 have_requests = 1;
467 }
468
469 if (have_requests)
470 blkdev->more_work++;
471 return send_notify;
472 }
473
474 /* walk finished list, send outstanding responses, free requests */
475 static void blk_send_response_all(struct XenBlkDev *blkdev)
476 {
477 struct ioreq *ioreq;
478 int send_notify = 0;
479
480 while (!QLIST_EMPTY(&blkdev->finished)) {
481 ioreq = QLIST_FIRST(&blkdev->finished);
482 send_notify += blk_send_response_one(ioreq);
483 ioreq_release(ioreq);
484 }
485 if (send_notify)
486 xen_be_send_notify(&blkdev->xendev);
487 }
488
489 static int blk_get_request(struct XenBlkDev *blkdev, struct ioreq *ioreq, RING_IDX rc)
490 {
491 switch (blkdev->protocol) {
492 case BLKIF_PROTOCOL_NATIVE:
493 memcpy(&ioreq->req, RING_GET_REQUEST(&blkdev->rings.native, rc),
494 sizeof(ioreq->req));
495 break;
496 case BLKIF_PROTOCOL_X86_32:
497 blkif_get_x86_32_req(&ioreq->req,
498 RING_GET_REQUEST(&blkdev->rings.x86_32_part, rc));
499 break;
500 case BLKIF_PROTOCOL_X86_64:
501 blkif_get_x86_64_req(&ioreq->req,
502 RING_GET_REQUEST(&blkdev->rings.x86_64_part, rc));
503 break;
504 }
505 return 0;
506 }
507
508 static void blk_handle_requests(struct XenBlkDev *blkdev)
509 {
510 RING_IDX rc, rp;
511 struct ioreq *ioreq;
512
513 blkdev->more_work = 0;
514
515 rc = blkdev->rings.common.req_cons;
516 rp = blkdev->rings.common.sring->req_prod;
517 xen_rmb(); /* Ensure we see queued requests up to 'rp'. */
518
519 if (use_aio)
520 blk_send_response_all(blkdev);
521 while (rc != rp) {
522 /* pull request from ring */
523 if (RING_REQUEST_CONS_OVERFLOW(&blkdev->rings.common, rc))
524 break;
525 ioreq = ioreq_start(blkdev);
526 if (ioreq == NULL) {
527 blkdev->more_work++;
528 break;
529 }
530 blk_get_request(blkdev, ioreq, rc);
531 blkdev->rings.common.req_cons = ++rc;
532
533 /* parse them */
534 if (ioreq_parse(ioreq) != 0) {
535 if (blk_send_response_one(ioreq))
536 xen_be_send_notify(&blkdev->xendev);
537 ioreq_release(ioreq);
538 continue;
539 }
540
541 if (use_aio) {
542 /* run i/o in aio mode */
543 ioreq_runio_qemu_aio(ioreq);
544 } else {
545 /* run i/o in sync mode */
546 ioreq_runio_qemu_sync(ioreq);
547 }
548 }
549 if (!use_aio)
550 blk_send_response_all(blkdev);
551
552 if (blkdev->more_work && blkdev->requests_inflight < max_requests)
553 qemu_bh_schedule(blkdev->bh);
554 }
555
556 /* ------------------------------------------------------------- */
557
558 static void blk_bh(void *opaque)
559 {
560 struct XenBlkDev *blkdev = opaque;
561 blk_handle_requests(blkdev);
562 }
563
564 static void blk_alloc(struct XenDevice *xendev)
565 {
566 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
567
568 QLIST_INIT(&blkdev->inflight);
569 QLIST_INIT(&blkdev->finished);
570 QLIST_INIT(&blkdev->freelist);
571 blkdev->bh = qemu_bh_new(blk_bh, blkdev);
572 if (xen_mode != XEN_EMULATE)
573 batch_maps = 1;
574 }
575
576 static int blk_init(struct XenDevice *xendev)
577 {
578 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
579 int index, qflags, have_barriers, info = 0;
580 char *h;
581
582 /* read xenstore entries */
583 if (blkdev->params == NULL) {
584 blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params");
585 h = strchr(blkdev->params, ':');
586 if (h != NULL) {
587 blkdev->fileproto = blkdev->params;
588 blkdev->filename = h+1;
589 *h = 0;
590 } else {
591 blkdev->fileproto = "<unset>";
592 blkdev->filename = blkdev->params;
593 }
594 }
595 if (blkdev->mode == NULL)
596 blkdev->mode = xenstore_read_be_str(&blkdev->xendev, "mode");
597 if (blkdev->type == NULL)
598 blkdev->type = xenstore_read_be_str(&blkdev->xendev, "type");
599 if (blkdev->dev == NULL)
600 blkdev->dev = xenstore_read_be_str(&blkdev->xendev, "dev");
601 if (blkdev->devtype == NULL)
602 blkdev->devtype = xenstore_read_be_str(&blkdev->xendev, "device-type");
603
604 /* do we have all we need? */
605 if (blkdev->params == NULL ||
606 blkdev->mode == NULL ||
607 blkdev->type == NULL ||
608 blkdev->dev == NULL)
609 return -1;
610
611 /* read-only ? */
612 if (strcmp(blkdev->mode, "w") == 0) {
613 qflags = BDRV_O_RDWR;
614 } else {
615 qflags = 0;
616 info |= VDISK_READONLY;
617 }
618
619 /* cdrom ? */
620 if (blkdev->devtype && !strcmp(blkdev->devtype, "cdrom"))
621 info |= VDISK_CDROM;
622
623 /* init qemu block driver */
624 index = (blkdev->xendev.dev - 202 * 256) / 16;
625 blkdev->dinfo = drive_get(IF_XEN, 0, index);
626 if (!blkdev->dinfo) {
627 /* setup via xenbus -> create new block driver instance */
628 xen_be_printf(&blkdev->xendev, 2, "create new bdrv (xenbus setup)\n");
629 blkdev->bs = bdrv_new(blkdev->dev);
630 if (blkdev->bs) {
631 if (bdrv_open(blkdev->bs, blkdev->filename, qflags,
632 bdrv_find_whitelisted_format(blkdev->fileproto))
633 != 0) {
634 bdrv_delete(blkdev->bs);
635 blkdev->bs = NULL;
636 }
637 }
638 if (!blkdev->bs)
639 return -1;
640 } else {
641 /* setup via qemu cmdline -> already setup for us */
642 xen_be_printf(&blkdev->xendev, 2, "get configured bdrv (cmdline setup)\n");
643 blkdev->bs = blkdev->dinfo->bdrv;
644 }
645 blkdev->file_blk = BLOCK_SIZE;
646 blkdev->file_size = bdrv_getlength(blkdev->bs);
647 if (blkdev->file_size < 0) {
648 xen_be_printf(&blkdev->xendev, 1, "bdrv_getlength: %d (%s) | drv %s\n",
649 (int)blkdev->file_size, strerror(-blkdev->file_size),
650 blkdev->bs->drv ? blkdev->bs->drv->format_name : "-");
651 blkdev->file_size = 0;
652 }
653 have_barriers = blkdev->bs->drv && blkdev->bs->drv->bdrv_flush ? 1 : 0;
654
655 xen_be_printf(xendev, 1, "type \"%s\", fileproto \"%s\", filename \"%s\","
656 " size %" PRId64 " (%" PRId64 " MB)\n",
657 blkdev->type, blkdev->fileproto, blkdev->filename,
658 blkdev->file_size, blkdev->file_size >> 20);
659
660 /* fill info */
661 xenstore_write_be_int(&blkdev->xendev, "feature-barrier", have_barriers);
662 xenstore_write_be_int(&blkdev->xendev, "info", info);
663 xenstore_write_be_int(&blkdev->xendev, "sector-size", blkdev->file_blk);
664 xenstore_write_be_int(&blkdev->xendev, "sectors",
665 blkdev->file_size / blkdev->file_blk);
666 return 0;
667 }
668
669 static int blk_connect(struct XenDevice *xendev)
670 {
671 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
672
673 if (xenstore_read_fe_int(&blkdev->xendev, "ring-ref", &blkdev->ring_ref) == -1)
674 return -1;
675 if (xenstore_read_fe_int(&blkdev->xendev, "event-channel",
676 &blkdev->xendev.remote_port) == -1)
677 return -1;
678
679 blkdev->protocol = BLKIF_PROTOCOL_NATIVE;
680 if (blkdev->xendev.protocol) {
681 if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_32) == 0)
682 blkdev->protocol = BLKIF_PROTOCOL_X86_32;
683 if (strcmp(blkdev->xendev.protocol, XEN_IO_PROTO_ABI_X86_64) == 0)
684 blkdev->protocol = BLKIF_PROTOCOL_X86_64;
685 }
686
687 blkdev->sring = xc_gnttab_map_grant_ref(blkdev->xendev.gnttabdev,
688 blkdev->xendev.dom,
689 blkdev->ring_ref,
690 PROT_READ | PROT_WRITE);
691 if (!blkdev->sring)
692 return -1;
693 blkdev->cnt_map++;
694
695 switch (blkdev->protocol) {
696 case BLKIF_PROTOCOL_NATIVE:
697 {
698 blkif_sring_t *sring_native = blkdev->sring;
699 BACK_RING_INIT(&blkdev->rings.native, sring_native, XC_PAGE_SIZE);
700 break;
701 }
702 case BLKIF_PROTOCOL_X86_32:
703 {
704 blkif_x86_32_sring_t *sring_x86_32 = blkdev->sring;
705
706 BACK_RING_INIT(&blkdev->rings.x86_32_part, sring_x86_32, XC_PAGE_SIZE);
707 break;
708 }
709 case BLKIF_PROTOCOL_X86_64:
710 {
711 blkif_x86_64_sring_t *sring_x86_64 = blkdev->sring;
712
713 BACK_RING_INIT(&blkdev->rings.x86_64_part, sring_x86_64, XC_PAGE_SIZE);
714 break;
715 }
716 }
717
718 xen_be_bind_evtchn(&blkdev->xendev);
719
720 xen_be_printf(&blkdev->xendev, 1, "ok: proto %s, ring-ref %d, "
721 "remote port %d, local port %d\n",
722 blkdev->xendev.protocol, blkdev->ring_ref,
723 blkdev->xendev.remote_port, blkdev->xendev.local_port);
724 return 0;
725 }
726
727 static void blk_disconnect(struct XenDevice *xendev)
728 {
729 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
730
731 if (blkdev->bs) {
732 if (!blkdev->dinfo) {
733 /* close/delete only if we created it ourself */
734 bdrv_close(blkdev->bs);
735 bdrv_delete(blkdev->bs);
736 }
737 blkdev->bs = NULL;
738 }
739 xen_be_unbind_evtchn(&blkdev->xendev);
740
741 if (blkdev->sring) {
742 xc_gnttab_munmap(blkdev->xendev.gnttabdev, blkdev->sring, 1);
743 blkdev->cnt_map--;
744 blkdev->sring = NULL;
745 }
746 }
747
748 static int blk_free(struct XenDevice *xendev)
749 {
750 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
751 struct ioreq *ioreq;
752
753 while (!QLIST_EMPTY(&blkdev->freelist)) {
754 ioreq = QLIST_FIRST(&blkdev->freelist);
755 QLIST_REMOVE(ioreq, list);
756 qemu_iovec_destroy(&ioreq->v);
757 qemu_free(ioreq);
758 }
759
760 qemu_free(blkdev->params);
761 qemu_free(blkdev->mode);
762 qemu_free(blkdev->type);
763 qemu_free(blkdev->dev);
764 qemu_free(blkdev->devtype);
765 qemu_bh_delete(blkdev->bh);
766 return 0;
767 }
768
769 static void blk_event(struct XenDevice *xendev)
770 {
771 struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev);
772
773 qemu_bh_schedule(blkdev->bh);
774 }
775
776 struct XenDevOps xen_blkdev_ops = {
777 .size = sizeof(struct XenBlkDev),
778 .flags = DEVOPS_FLAG_NEED_GNTDEV,
779 .alloc = blk_alloc,
780 .init = blk_init,
781 .connect = blk_connect,
782 .disconnect = blk_disconnect,
783 .event = blk_event,
784 .free = blk_free,
785 };
Stefan Hajnoczi's qemu-kvm.git repo