block: honor BDRV_O_ALLOW_RDWR when clearing bs->read_only
[qemu.git] / block / blkverify.c
1 /*
2 * Block protocol for block driver correctness testing
3 *
4 * Copyright (C) 2010 IBM, Corp.
5 *
6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
7 * See the COPYING file in the top-level directory.
8 */
9
10 #include "qemu/osdep.h"
11 #include "qapi/error.h"
12 #include "qemu/sockets.h" /* for EINPROGRESS on Windows */
13 #include "block/block_int.h"
14 #include "qapi/qmp/qdict.h"
15 #include "qapi/qmp/qstring.h"
16 #include "qemu/cutils.h"
17
18 typedef struct {
19 BdrvChild *test_file;
20 } BDRVBlkverifyState;
21
22 typedef struct BlkverifyRequest {
23 Coroutine *co;
24 BlockDriverState *bs;
25
26 /* Request metadata */
27 bool is_write;
28 uint64_t offset;
29 uint64_t bytes;
30 int flags;
31
32 int (*request_fn)(BdrvChild *, int64_t, unsigned int, QEMUIOVector *,
33 BdrvRequestFlags);
34
35 int ret; /* test image result */
36 int raw_ret; /* raw image result */
37
38 unsigned int done; /* completion counter */
39
40 QEMUIOVector *qiov; /* user I/O vector */
41 QEMUIOVector *raw_qiov; /* cloned I/O vector for raw file */
42 } BlkverifyRequest;
43
44 static void GCC_FMT_ATTR(2, 3) blkverify_err(BlkverifyRequest *r,
45 const char *fmt, ...)
46 {
47 va_list ap;
48
49 va_start(ap, fmt);
50 fprintf(stderr, "blkverify: %s offset=%" PRId64 " bytes=%" PRId64 " ",
51 r->is_write ? "write" : "read", r->offset, r->bytes);
52 vfprintf(stderr, fmt, ap);
53 fprintf(stderr, "\n");
54 va_end(ap);
55 exit(1);
56 }
57
58 /* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
59 static void blkverify_parse_filename(const char *filename, QDict *options,
60 Error **errp)
61 {
62 const char *c;
63 QString *raw_path;
64
65
66 /* Parse the blkverify: prefix */
67 if (!strstart(filename, "blkverify:", &filename)) {
68 /* There was no prefix; therefore, all options have to be already
69 present in the QDict (except for the filename) */
70 qdict_put(options, "x-image", qstring_from_str(filename));
71 return;
72 }
73
74 /* Parse the raw image filename */
75 c = strchr(filename, ':');
76 if (c == NULL) {
77 error_setg(errp, "blkverify requires raw copy and original image path");
78 return;
79 }
80
81 /* TODO Implement option pass-through and set raw.filename here */
82 raw_path = qstring_from_substr(filename, 0, c - filename - 1);
83 qdict_put(options, "x-raw", raw_path);
84
85 /* TODO Allow multi-level nesting and set file.filename here */
86 filename = c + 1;
87 qdict_put(options, "x-image", qstring_from_str(filename));
88 }
89
90 static QemuOptsList runtime_opts = {
91 .name = "blkverify",
92 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
93 .desc = {
94 {
95 .name = "x-raw",
96 .type = QEMU_OPT_STRING,
97 .help = "[internal use only, will be removed]",
98 },
99 {
100 .name = "x-image",
101 .type = QEMU_OPT_STRING,
102 .help = "[internal use only, will be removed]",
103 },
104 { /* end of list */ }
105 },
106 };
107
108 static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
109 Error **errp)
110 {
111 BDRVBlkverifyState *s = bs->opaque;
112 QemuOpts *opts;
113 Error *local_err = NULL;
114 int ret;
115
116 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
117 qemu_opts_absorb_qdict(opts, options, &local_err);
118 if (local_err) {
119 error_propagate(errp, local_err);
120 ret = -EINVAL;
121 goto fail;
122 }
123
124 /* Open the raw file */
125 bs->file = bdrv_open_child(qemu_opt_get(opts, "x-raw"), options, "raw",
126 bs, &child_file, false, &local_err);
127 if (local_err) {
128 ret = -EINVAL;
129 error_propagate(errp, local_err);
130 goto fail;
131 }
132
133 /* Open the test file */
134 s->test_file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options,
135 "test", bs, &child_format, false,
136 &local_err);
137 if (local_err) {
138 ret = -EINVAL;
139 error_propagate(errp, local_err);
140 goto fail;
141 }
142
143 ret = 0;
144 fail:
145 if (ret < 0) {
146 bdrv_unref_child(bs, bs->file);
147 }
148 qemu_opts_del(opts);
149 return ret;
150 }
151
152 static void blkverify_close(BlockDriverState *bs)
153 {
154 BDRVBlkverifyState *s = bs->opaque;
155
156 bdrv_unref_child(bs, s->test_file);
157 s->test_file = NULL;
158 }
159
160 static int64_t blkverify_getlength(BlockDriverState *bs)
161 {
162 BDRVBlkverifyState *s = bs->opaque;
163
164 return bdrv_getlength(s->test_file->bs);
165 }
166
167 static void coroutine_fn blkverify_do_test_req(void *opaque)
168 {
169 BlkverifyRequest *r = opaque;
170 BDRVBlkverifyState *s = r->bs->opaque;
171
172 r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov,
173 r->flags);
174 r->done++;
175 qemu_coroutine_enter_if_inactive(r->co);
176 }
177
178 static void coroutine_fn blkverify_do_raw_req(void *opaque)
179 {
180 BlkverifyRequest *r = opaque;
181
182 r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov,
183 r->flags);
184 r->done++;
185 qemu_coroutine_enter_if_inactive(r->co);
186 }
187
188 static int coroutine_fn
189 blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset,
190 uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov,
191 int flags, bool is_write)
192 {
193 Coroutine *co_a, *co_b;
194
195 *r = (BlkverifyRequest) {
196 .co = qemu_coroutine_self(),
197 .bs = bs,
198 .offset = offset,
199 .bytes = bytes,
200 .qiov = qiov,
201 .raw_qiov = raw_qiov,
202 .flags = flags,
203 .is_write = is_write,
204 .request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv,
205 };
206
207 co_a = qemu_coroutine_create(blkverify_do_test_req, r);
208 co_b = qemu_coroutine_create(blkverify_do_raw_req, r);
209
210 qemu_coroutine_enter(co_a);
211 qemu_coroutine_enter(co_b);
212
213 while (r->done < 2) {
214 qemu_coroutine_yield();
215 }
216
217 if (r->ret != r->raw_ret) {
218 blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret);
219 }
220
221 return r->ret;
222 }
223
224 static int coroutine_fn
225 blkverify_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
226 QEMUIOVector *qiov, int flags)
227 {
228 BlkverifyRequest r;
229 QEMUIOVector raw_qiov;
230 void *buf;
231 ssize_t cmp_offset;
232 int ret;
233
234 buf = qemu_blockalign(bs->file->bs, qiov->size);
235 qemu_iovec_init(&raw_qiov, qiov->niov);
236 qemu_iovec_clone(&raw_qiov, qiov, buf);
237
238 ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, flags,
239 false);
240
241 cmp_offset = qemu_iovec_compare(qiov, &raw_qiov);
242 if (cmp_offset != -1) {
243 blkverify_err(&r, "contents mismatch at offset %" PRId64,
244 offset + cmp_offset);
245 }
246
247 qemu_iovec_destroy(&raw_qiov);
248 qemu_vfree(buf);
249
250 return ret;
251 }
252
253 static int coroutine_fn
254 blkverify_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
255 QEMUIOVector *qiov, int flags)
256 {
257 BlkverifyRequest r;
258 return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true);
259 }
260
261 static int blkverify_co_flush(BlockDriverState *bs)
262 {
263 BDRVBlkverifyState *s = bs->opaque;
264
265 /* Only flush test file, the raw file is not important */
266 return bdrv_co_flush(s->test_file->bs);
267 }
268
269 static bool blkverify_recurse_is_first_non_filter(BlockDriverState *bs,
270 BlockDriverState *candidate)
271 {
272 BDRVBlkverifyState *s = bs->opaque;
273
274 bool perm = bdrv_recurse_is_first_non_filter(bs->file->bs, candidate);
275
276 if (perm) {
277 return true;
278 }
279
280 return bdrv_recurse_is_first_non_filter(s->test_file->bs, candidate);
281 }
282
283 static void blkverify_refresh_filename(BlockDriverState *bs, QDict *options)
284 {
285 BDRVBlkverifyState *s = bs->opaque;
286
287 /* bs->file->bs has already been refreshed */
288 bdrv_refresh_filename(s->test_file->bs);
289
290 if (bs->file->bs->full_open_options
291 && s->test_file->bs->full_open_options)
292 {
293 QDict *opts = qdict_new();
294 qdict_put_obj(opts, "driver", QOBJECT(qstring_from_str("blkverify")));
295
296 QINCREF(bs->file->bs->full_open_options);
297 qdict_put_obj(opts, "raw", QOBJECT(bs->file->bs->full_open_options));
298 QINCREF(s->test_file->bs->full_open_options);
299 qdict_put_obj(opts, "test",
300 QOBJECT(s->test_file->bs->full_open_options));
301
302 bs->full_open_options = opts;
303 }
304
305 if (bs->file->bs->exact_filename[0]
306 && s->test_file->bs->exact_filename[0])
307 {
308 snprintf(bs->exact_filename, sizeof(bs->exact_filename),
309 "blkverify:%s:%s",
310 bs->file->bs->exact_filename,
311 s->test_file->bs->exact_filename);
312 }
313 }
314
315 static BlockDriver bdrv_blkverify = {
316 .format_name = "blkverify",
317 .protocol_name = "blkverify",
318 .instance_size = sizeof(BDRVBlkverifyState),
319
320 .bdrv_parse_filename = blkverify_parse_filename,
321 .bdrv_file_open = blkverify_open,
322 .bdrv_close = blkverify_close,
323 .bdrv_child_perm = bdrv_filter_default_perms,
324 .bdrv_getlength = blkverify_getlength,
325 .bdrv_refresh_filename = blkverify_refresh_filename,
326
327 .bdrv_co_preadv = blkverify_co_preadv,
328 .bdrv_co_pwritev = blkverify_co_pwritev,
329 .bdrv_co_flush = blkverify_co_flush,
330
331 .is_filter = true,
332 .bdrv_recurse_is_first_non_filter = blkverify_recurse_is_first_non_filter,
333 };
334
335 static void bdrv_blkverify_init(void)
336 {
337 bdrv_register(&bdrv_blkverify);
338 }
339
340 block_init(bdrv_blkverify_init);