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-io.h"
14 #include "block/block_int.h"
15 #include "qobject/qdict.h"
16 #include "qobject/qstring.h"
17 #include "qemu/cutils.h"
18 #include "qemu/module.h"
19 #include "qemu/option.h"
20 #include "qemu/memalign.h"
21
22 typedef struct {
23 BdrvChild *test_file;
24 } BDRVBlkverifyState;
25
26 typedef struct BlkverifyRequest {
27 Coroutine *co;
28 BlockDriverState *bs;
29
30 /* Request metadata */
31 bool is_write;
32 uint64_t offset;
33 uint64_t bytes;
34 int flags;
35
36 int GRAPH_RDLOCK_PTR (*request_fn)(
37 BdrvChild *, int64_t, int64_t, QEMUIOVector *, BdrvRequestFlags);
38
39 int ret; /* test image result */
40 int raw_ret; /* raw image result */
41
42 unsigned int done; /* completion counter */
43
44 QEMUIOVector *qiov; /* user I/O vector */
45 QEMUIOVector *raw_qiov; /* cloned I/O vector for raw file */
46 } BlkverifyRequest;
47
blkverify_err(BlkverifyRequest * r,const char * fmt,...)48 static void G_GNUC_PRINTF(2, 3) blkverify_err(BlkverifyRequest *r,
49 const char *fmt, ...)
50 {
51 va_list ap;
52
53 va_start(ap, fmt);
54 fprintf(stderr, "blkverify: %s offset=%" PRId64 " bytes=%" PRId64 " ",
55 r->is_write ? "write" : "read", r->offset, r->bytes);
56 vfprintf(stderr, fmt, ap);
57 fprintf(stderr, "\n");
58 va_end(ap);
59 exit(1);
60 }
61
62 /* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */
blkverify_parse_filename(const char * filename,QDict * options,Error ** errp)63 static void blkverify_parse_filename(const char *filename, QDict *options,
64 Error **errp)
65 {
66 const char *c;
67 QString *raw_path;
68
69
70 /* Parse the blkverify: prefix */
71 if (!strstart(filename, "blkverify:", &filename)) {
72 /* There was no prefix; therefore, all options have to be already
73 present in the QDict (except for the filename) */
74 qdict_put_str(options, "x-image", filename);
75 return;
76 }
77
78 /* Parse the raw image filename */
79 c = strchr(filename, ':');
80 if (c == NULL) {
81 error_setg(errp, "blkverify requires raw copy and original image path");
82 return;
83 }
84
85 /* TODO Implement option pass-through and set raw.filename here */
86 raw_path = qstring_from_substr(filename, 0, c - filename);
87 qdict_put(options, "x-raw", raw_path);
88
89 /* TODO Allow multi-level nesting and set file.filename here */
90 filename = c + 1;
91 qdict_put_str(options, "x-image", filename);
92 }
93
94 static QemuOptsList runtime_opts = {
95 .name = "blkverify",
96 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
97 .desc = {
98 {
99 .name = "x-raw",
100 .type = QEMU_OPT_STRING,
101 .help = "[internal use only, will be removed]",
102 },
103 {
104 .name = "x-image",
105 .type = QEMU_OPT_STRING,
106 .help = "[internal use only, will be removed]",
107 },
108 { /* end of list */ }
109 },
110 };
111
blkverify_open(BlockDriverState * bs,QDict * options,int flags,Error ** errp)112 static int blkverify_open(BlockDriverState *bs, QDict *options, int flags,
113 Error **errp)
114 {
115 BDRVBlkverifyState *s = bs->opaque;
116 QemuOpts *opts;
117 int ret;
118
119 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
120 if (!qemu_opts_absorb_qdict(opts, options, errp)) {
121 ret = -EINVAL;
122 goto fail;
123 }
124
125 /* Open the raw file */
126 ret = bdrv_open_file_child(qemu_opt_get(opts, "x-raw"), options, "raw",
127 bs, errp);
128 if (ret < 0) {
129 goto fail;
130 }
131
132 /* Open the test file */
133 s->test_file = bdrv_open_child(qemu_opt_get(opts, "x-image"), options,
134 "test", bs, &child_of_bds, BDRV_CHILD_DATA,
135 false, errp);
136 if (!s->test_file) {
137 ret = -EINVAL;
138 goto fail;
139 }
140
141 bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED;
142 bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED;
143
144 ret = 0;
145 fail:
146 qemu_opts_del(opts);
147 return ret;
148 }
149
blkverify_close(BlockDriverState * bs)150 static void blkverify_close(BlockDriverState *bs)
151 {
152 BDRVBlkverifyState *s = bs->opaque;
153
154 bdrv_drain_all_begin();
155 bdrv_graph_wrlock();
156 bdrv_unref_child(bs, s->test_file);
157 s->test_file = NULL;
158 bdrv_graph_wrunlock();
159 bdrv_drain_all_end();
160 }
161
162 static int64_t coroutine_fn GRAPH_RDLOCK
blkverify_co_getlength(BlockDriverState * bs)163 blkverify_co_getlength(BlockDriverState *bs)
164 {
165 BDRVBlkverifyState *s = bs->opaque;
166
167 return bdrv_co_getlength(s->test_file->bs);
168 }
169
blkverify_do_test_req(void * opaque)170 static void coroutine_fn blkverify_do_test_req(void *opaque)
171 {
172 BlkverifyRequest *r = opaque;
173 BDRVBlkverifyState *s = r->bs->opaque;
174
175 bdrv_graph_co_rdlock();
176 r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov,
177 r->flags);
178 bdrv_graph_co_rdunlock();
179
180 r->done++;
181 qemu_coroutine_enter_if_inactive(r->co);
182 }
183
blkverify_do_raw_req(void * opaque)184 static void coroutine_fn blkverify_do_raw_req(void *opaque)
185 {
186 BlkverifyRequest *r = opaque;
187
188 bdrv_graph_co_rdlock();
189 r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov,
190 r->flags);
191 bdrv_graph_co_rdunlock();
192
193 r->done++;
194 qemu_coroutine_enter_if_inactive(r->co);
195 }
196
197 static int coroutine_fn GRAPH_RDLOCK
blkverify_co_prwv(BlockDriverState * bs,BlkverifyRequest * r,uint64_t offset,uint64_t bytes,QEMUIOVector * qiov,QEMUIOVector * raw_qiov,int flags,bool is_write)198 blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset,
199 uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov,
200 int flags, bool is_write)
201 {
202 Coroutine *co_a, *co_b;
203
204 *r = (BlkverifyRequest) {
205 .co = qemu_coroutine_self(),
206 .bs = bs,
207 .offset = offset,
208 .bytes = bytes,
209 .qiov = qiov,
210 .raw_qiov = raw_qiov,
211 .flags = flags,
212 .is_write = is_write,
213 .request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv,
214 };
215
216 co_a = qemu_coroutine_create(blkverify_do_test_req, r);
217 co_b = qemu_coroutine_create(blkverify_do_raw_req, r);
218
219 qemu_coroutine_enter(co_a);
220 qemu_coroutine_enter(co_b);
221
222 while (r->done < 2) {
223 qemu_coroutine_yield();
224 }
225
226 if (r->ret != r->raw_ret) {
227 blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret);
228 }
229
230 return r->ret;
231 }
232
233 static int coroutine_fn GRAPH_RDLOCK
blkverify_co_preadv(BlockDriverState * bs,int64_t offset,int64_t bytes,QEMUIOVector * qiov,BdrvRequestFlags flags)234 blkverify_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes,
235 QEMUIOVector *qiov, BdrvRequestFlags flags)
236 {
237 BlkverifyRequest r;
238 QEMUIOVector raw_qiov;
239 void *buf;
240 ssize_t cmp_offset;
241 int ret;
242
243 buf = qemu_blockalign(bs->file->bs, qiov->size);
244 qemu_iovec_init(&raw_qiov, qiov->niov);
245 qemu_iovec_clone(&raw_qiov, qiov, buf);
246
247 ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov,
248 flags & ~BDRV_REQ_REGISTERED_BUF, false);
249
250 cmp_offset = qemu_iovec_compare(qiov, &raw_qiov);
251 if (cmp_offset != -1) {
252 blkverify_err(&r, "contents mismatch at offset %" PRId64,
253 offset + cmp_offset);
254 }
255
256 qemu_iovec_destroy(&raw_qiov);
257 qemu_vfree(buf);
258
259 return ret;
260 }
261
262 static int coroutine_fn GRAPH_RDLOCK
blkverify_co_pwritev(BlockDriverState * bs,int64_t offset,int64_t bytes,QEMUIOVector * qiov,BdrvRequestFlags flags)263 blkverify_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes,
264 QEMUIOVector *qiov, BdrvRequestFlags flags)
265 {
266 BlkverifyRequest r;
267 return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true);
268 }
269
blkverify_co_flush(BlockDriverState * bs)270 static int coroutine_fn GRAPH_RDLOCK blkverify_co_flush(BlockDriverState *bs)
271 {
272 BDRVBlkverifyState *s = bs->opaque;
273
274 /* Only flush test file, the raw file is not important */
275 return bdrv_co_flush(s->test_file->bs);
276 }
277
278 static bool GRAPH_RDLOCK
blkverify_recurse_can_replace(BlockDriverState * bs,BlockDriverState * to_replace)279 blkverify_recurse_can_replace(BlockDriverState *bs,
280 BlockDriverState *to_replace)
281 {
282 BDRVBlkverifyState *s = bs->opaque;
283
284 /*
285 * blkverify quits the whole qemu process if there is a mismatch
286 * between bs->file->bs and s->test_file->bs. Therefore, we know
287 * know that both must match bs and we can recurse down to either.
288 */
289 return bdrv_recurse_can_replace(bs->file->bs, to_replace) ||
290 bdrv_recurse_can_replace(s->test_file->bs, to_replace);
291 }
292
blkverify_refresh_filename(BlockDriverState * bs)293 static void GRAPH_RDLOCK blkverify_refresh_filename(BlockDriverState *bs)
294 {
295 BDRVBlkverifyState *s = bs->opaque;
296
297 if (bs->file->bs->exact_filename[0]
298 && s->test_file->bs->exact_filename[0])
299 {
300 int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename),
301 "blkverify:%s:%s",
302 bs->file->bs->exact_filename,
303 s->test_file->bs->exact_filename);
304 if (ret >= sizeof(bs->exact_filename)) {
305 /* An overflow makes the filename unusable, so do not report any */
306 bs->exact_filename[0] = 0;
307 }
308 }
309 }
310
blkverify_dirname(BlockDriverState * bs,Error ** errp)311 static char *blkverify_dirname(BlockDriverState *bs, Error **errp)
312 {
313 /* In general, there are two BDSs with different dirnames below this one;
314 * so there is no unique dirname we could return (unless both are equal by
315 * chance). Therefore, to be consistent, just always return NULL. */
316 error_setg(errp, "Cannot generate a base directory for blkverify nodes");
317 return NULL;
318 }
319
320 static BlockDriver bdrv_blkverify = {
321 .format_name = "blkverify",
322 .protocol_name = "blkverify",
323 .instance_size = sizeof(BDRVBlkverifyState),
324
325 .bdrv_parse_filename = blkverify_parse_filename,
326 .bdrv_open = blkverify_open,
327 .bdrv_close = blkverify_close,
328 .bdrv_child_perm = bdrv_default_perms,
329 .bdrv_co_getlength = blkverify_co_getlength,
330 .bdrv_refresh_filename = blkverify_refresh_filename,
331 .bdrv_dirname = blkverify_dirname,
332
333 .bdrv_co_preadv = blkverify_co_preadv,
334 .bdrv_co_pwritev = blkverify_co_pwritev,
335 .bdrv_co_flush = blkverify_co_flush,
336
337 .is_filter = true,
338 .bdrv_recurse_can_replace = blkverify_recurse_can_replace,
339 };
340
bdrv_blkverify_init(void)341 static void bdrv_blkverify_init(void)
342 {
343 bdrv_register(&bdrv_blkverify);
344 }
345
346 block_init(bdrv_blkverify_init);
347