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 "qapi/qmp/qdict.h" 16 #include "qapi/qmp/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 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 */ 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 }; 111 112 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 } 149 150 static void blkverify_close(BlockDriverState *bs) 151 { 152 BDRVBlkverifyState *s = bs->opaque; 153 154 bdrv_graph_wrlock(); 155 bdrv_unref_child(bs, s->test_file); 156 s->test_file = NULL; 157 bdrv_graph_wrunlock(); 158 } 159 160 static int64_t coroutine_fn GRAPH_RDLOCK 161 blkverify_co_getlength(BlockDriverState *bs) 162 { 163 BDRVBlkverifyState *s = bs->opaque; 164 165 return bdrv_co_getlength(s->test_file->bs); 166 } 167 168 static void coroutine_fn blkverify_do_test_req(void *opaque) 169 { 170 BlkverifyRequest *r = opaque; 171 BDRVBlkverifyState *s = r->bs->opaque; 172 173 bdrv_graph_co_rdlock(); 174 r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov, 175 r->flags); 176 bdrv_graph_co_rdunlock(); 177 178 r->done++; 179 qemu_coroutine_enter_if_inactive(r->co); 180 } 181 182 static void coroutine_fn blkverify_do_raw_req(void *opaque) 183 { 184 BlkverifyRequest *r = opaque; 185 186 bdrv_graph_co_rdlock(); 187 r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov, 188 r->flags); 189 bdrv_graph_co_rdunlock(); 190 191 r->done++; 192 qemu_coroutine_enter_if_inactive(r->co); 193 } 194 195 static int coroutine_fn GRAPH_RDLOCK 196 blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset, 197 uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov, 198 int flags, bool is_write) 199 { 200 Coroutine *co_a, *co_b; 201 202 *r = (BlkverifyRequest) { 203 .co = qemu_coroutine_self(), 204 .bs = bs, 205 .offset = offset, 206 .bytes = bytes, 207 .qiov = qiov, 208 .raw_qiov = raw_qiov, 209 .flags = flags, 210 .is_write = is_write, 211 .request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv, 212 }; 213 214 co_a = qemu_coroutine_create(blkverify_do_test_req, r); 215 co_b = qemu_coroutine_create(blkverify_do_raw_req, r); 216 217 qemu_coroutine_enter(co_a); 218 qemu_coroutine_enter(co_b); 219 220 while (r->done < 2) { 221 qemu_coroutine_yield(); 222 } 223 224 if (r->ret != r->raw_ret) { 225 blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret); 226 } 227 228 return r->ret; 229 } 230 231 static int coroutine_fn GRAPH_RDLOCK 232 blkverify_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes, 233 QEMUIOVector *qiov, BdrvRequestFlags flags) 234 { 235 BlkverifyRequest r; 236 QEMUIOVector raw_qiov; 237 void *buf; 238 ssize_t cmp_offset; 239 int ret; 240 241 buf = qemu_blockalign(bs->file->bs, qiov->size); 242 qemu_iovec_init(&raw_qiov, qiov->niov); 243 qemu_iovec_clone(&raw_qiov, qiov, buf); 244 245 ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, 246 flags & ~BDRV_REQ_REGISTERED_BUF, false); 247 248 cmp_offset = qemu_iovec_compare(qiov, &raw_qiov); 249 if (cmp_offset != -1) { 250 blkverify_err(&r, "contents mismatch at offset %" PRId64, 251 offset + cmp_offset); 252 } 253 254 qemu_iovec_destroy(&raw_qiov); 255 qemu_vfree(buf); 256 257 return ret; 258 } 259 260 static int coroutine_fn GRAPH_RDLOCK 261 blkverify_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes, 262 QEMUIOVector *qiov, BdrvRequestFlags flags) 263 { 264 BlkverifyRequest r; 265 return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true); 266 } 267 268 static int coroutine_fn GRAPH_RDLOCK blkverify_co_flush(BlockDriverState *bs) 269 { 270 BDRVBlkverifyState *s = bs->opaque; 271 272 /* Only flush test file, the raw file is not important */ 273 return bdrv_co_flush(s->test_file->bs); 274 } 275 276 static bool GRAPH_RDLOCK 277 blkverify_recurse_can_replace(BlockDriverState *bs, 278 BlockDriverState *to_replace) 279 { 280 BDRVBlkverifyState *s = bs->opaque; 281 282 /* 283 * blkverify quits the whole qemu process if there is a mismatch 284 * between bs->file->bs and s->test_file->bs. Therefore, we know 285 * know that both must match bs and we can recurse down to either. 286 */ 287 return bdrv_recurse_can_replace(bs->file->bs, to_replace) || 288 bdrv_recurse_can_replace(s->test_file->bs, to_replace); 289 } 290 291 static void GRAPH_RDLOCK blkverify_refresh_filename(BlockDriverState *bs) 292 { 293 BDRVBlkverifyState *s = bs->opaque; 294 295 if (bs->file->bs->exact_filename[0] 296 && s->test_file->bs->exact_filename[0]) 297 { 298 int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 299 "blkverify:%s:%s", 300 bs->file->bs->exact_filename, 301 s->test_file->bs->exact_filename); 302 if (ret >= sizeof(bs->exact_filename)) { 303 /* An overflow makes the filename unusable, so do not report any */ 304 bs->exact_filename[0] = 0; 305 } 306 } 307 } 308 309 static char *blkverify_dirname(BlockDriverState *bs, Error **errp) 310 { 311 /* In general, there are two BDSs with different dirnames below this one; 312 * so there is no unique dirname we could return (unless both are equal by 313 * chance). Therefore, to be consistent, just always return NULL. */ 314 error_setg(errp, "Cannot generate a base directory for blkverify nodes"); 315 return NULL; 316 } 317 318 static BlockDriver bdrv_blkverify = { 319 .format_name = "blkverify", 320 .protocol_name = "blkverify", 321 .instance_size = sizeof(BDRVBlkverifyState), 322 323 .bdrv_parse_filename = blkverify_parse_filename, 324 .bdrv_open = blkverify_open, 325 .bdrv_close = blkverify_close, 326 .bdrv_child_perm = bdrv_default_perms, 327 .bdrv_co_getlength = blkverify_co_getlength, 328 .bdrv_refresh_filename = blkverify_refresh_filename, 329 .bdrv_dirname = blkverify_dirname, 330 331 .bdrv_co_preadv = blkverify_co_preadv, 332 .bdrv_co_pwritev = blkverify_co_pwritev, 333 .bdrv_co_flush = blkverify_co_flush, 334 335 .is_filter = true, 336 .bdrv_recurse_can_replace = blkverify_recurse_can_replace, 337 }; 338 339 static void bdrv_blkverify_init(void) 340 { 341 bdrv_register(&bdrv_blkverify); 342 } 343 344 block_init(bdrv_blkverify_init); 345