blkverify.c (10109B)
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#include "qemu/module.h" 18#include "qemu/option.h" 19 20typedef struct { 21 BdrvChild *test_file; 22} BDRVBlkverifyState; 23 24typedef struct BlkverifyRequest { 25 Coroutine *co; 26 BlockDriverState *bs; 27 28 /* Request metadata */ 29 bool is_write; 30 uint64_t offset; 31 uint64_t bytes; 32 int flags; 33 34 int (*request_fn)(BdrvChild *, int64_t, int64_t, QEMUIOVector *, 35 BdrvRequestFlags); 36 37 int ret; /* test image result */ 38 int raw_ret; /* raw image result */ 39 40 unsigned int done; /* completion counter */ 41 42 QEMUIOVector *qiov; /* user I/O vector */ 43 QEMUIOVector *raw_qiov; /* cloned I/O vector for raw file */ 44} BlkverifyRequest; 45 46static void GCC_FMT_ATTR(2, 3) blkverify_err(BlkverifyRequest *r, 47 const char *fmt, ...) 48{ 49 va_list ap; 50 51 va_start(ap, fmt); 52 fprintf(stderr, "blkverify: %s offset=%" PRId64 " bytes=%" PRId64 " ", 53 r->is_write ? "write" : "read", r->offset, r->bytes); 54 vfprintf(stderr, fmt, ap); 55 fprintf(stderr, "\n"); 56 va_end(ap); 57 exit(1); 58} 59 60/* Valid blkverify filenames look like blkverify:path/to/raw_image:path/to/image */ 61static void blkverify_parse_filename(const char *filename, QDict *options, 62 Error **errp) 63{ 64 const char *c; 65 QString *raw_path; 66 67 68 /* Parse the blkverify: prefix */ 69 if (!strstart(filename, "blkverify:", &filename)) { 70 /* There was no prefix; therefore, all options have to be already 71 present in the QDict (except for the filename) */ 72 qdict_put_str(options, "x-image", filename); 73 return; 74 } 75 76 /* Parse the raw image filename */ 77 c = strchr(filename, ':'); 78 if (c == NULL) { 79 error_setg(errp, "blkverify requires raw copy and original image path"); 80 return; 81 } 82 83 /* TODO Implement option pass-through and set raw.filename here */ 84 raw_path = qstring_from_substr(filename, 0, c - filename); 85 qdict_put(options, "x-raw", raw_path); 86 87 /* TODO Allow multi-level nesting and set file.filename here */ 88 filename = c + 1; 89 qdict_put_str(options, "x-image", filename); 90} 91 92static QemuOptsList runtime_opts = { 93 .name = "blkverify", 94 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 95 .desc = { 96 { 97 .name = "x-raw", 98 .type = QEMU_OPT_STRING, 99 .help = "[internal use only, will be removed]", 100 }, 101 { 102 .name = "x-image", 103 .type = QEMU_OPT_STRING, 104 .help = "[internal use only, will be removed]", 105 }, 106 { /* end of list */ } 107 }, 108}; 109 110static int blkverify_open(BlockDriverState *bs, QDict *options, int flags, 111 Error **errp) 112{ 113 BDRVBlkverifyState *s = bs->opaque; 114 QemuOpts *opts; 115 int ret; 116 117 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 118 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 119 ret = -EINVAL; 120 goto fail; 121 } 122 123 /* Open the raw file */ 124 bs->file = bdrv_open_child(qemu_opt_get(opts, "x-raw"), options, "raw", 125 bs, &child_of_bds, 126 BDRV_CHILD_FILTERED | BDRV_CHILD_PRIMARY, 127 false, errp); 128 if (!bs->file) { 129 ret = -EINVAL; 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_of_bds, BDRV_CHILD_DATA, 136 false, errp); 137 if (!s->test_file) { 138 ret = -EINVAL; 139 goto fail; 140 } 141 142 bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED; 143 bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED; 144 145 ret = 0; 146fail: 147 qemu_opts_del(opts); 148 return ret; 149} 150 151static void blkverify_close(BlockDriverState *bs) 152{ 153 BDRVBlkverifyState *s = bs->opaque; 154 155 bdrv_unref_child(bs, s->test_file); 156 s->test_file = NULL; 157} 158 159static int64_t blkverify_getlength(BlockDriverState *bs) 160{ 161 BDRVBlkverifyState *s = bs->opaque; 162 163 return bdrv_getlength(s->test_file->bs); 164} 165 166static void coroutine_fn blkverify_do_test_req(void *opaque) 167{ 168 BlkverifyRequest *r = opaque; 169 BDRVBlkverifyState *s = r->bs->opaque; 170 171 r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov, 172 r->flags); 173 r->done++; 174 qemu_coroutine_enter_if_inactive(r->co); 175} 176 177static void coroutine_fn blkverify_do_raw_req(void *opaque) 178{ 179 BlkverifyRequest *r = opaque; 180 181 r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov, 182 r->flags); 183 r->done++; 184 qemu_coroutine_enter_if_inactive(r->co); 185} 186 187static int coroutine_fn 188blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset, 189 uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov, 190 int flags, bool is_write) 191{ 192 Coroutine *co_a, *co_b; 193 194 *r = (BlkverifyRequest) { 195 .co = qemu_coroutine_self(), 196 .bs = bs, 197 .offset = offset, 198 .bytes = bytes, 199 .qiov = qiov, 200 .raw_qiov = raw_qiov, 201 .flags = flags, 202 .is_write = is_write, 203 .request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv, 204 }; 205 206 co_a = qemu_coroutine_create(blkverify_do_test_req, r); 207 co_b = qemu_coroutine_create(blkverify_do_raw_req, r); 208 209 qemu_coroutine_enter(co_a); 210 qemu_coroutine_enter(co_b); 211 212 while (r->done < 2) { 213 qemu_coroutine_yield(); 214 } 215 216 if (r->ret != r->raw_ret) { 217 blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret); 218 } 219 220 return r->ret; 221} 222 223static int coroutine_fn 224blkverify_co_preadv(BlockDriverState *bs, int64_t offset, int64_t bytes, 225 QEMUIOVector *qiov, BdrvRequestFlags flags) 226{ 227 BlkverifyRequest r; 228 QEMUIOVector raw_qiov; 229 void *buf; 230 ssize_t cmp_offset; 231 int ret; 232 233 buf = qemu_blockalign(bs->file->bs, qiov->size); 234 qemu_iovec_init(&raw_qiov, qiov->niov); 235 qemu_iovec_clone(&raw_qiov, qiov, buf); 236 237 ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, flags, 238 false); 239 240 cmp_offset = qemu_iovec_compare(qiov, &raw_qiov); 241 if (cmp_offset != -1) { 242 blkverify_err(&r, "contents mismatch at offset %" PRId64, 243 offset + cmp_offset); 244 } 245 246 qemu_iovec_destroy(&raw_qiov); 247 qemu_vfree(buf); 248 249 return ret; 250} 251 252static int coroutine_fn 253blkverify_co_pwritev(BlockDriverState *bs, int64_t offset, int64_t bytes, 254 QEMUIOVector *qiov, BdrvRequestFlags flags) 255{ 256 BlkverifyRequest r; 257 return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true); 258} 259 260static int blkverify_co_flush(BlockDriverState *bs) 261{ 262 BDRVBlkverifyState *s = bs->opaque; 263 264 /* Only flush test file, the raw file is not important */ 265 return bdrv_co_flush(s->test_file->bs); 266} 267 268static bool blkverify_recurse_can_replace(BlockDriverState *bs, 269 BlockDriverState *to_replace) 270{ 271 BDRVBlkverifyState *s = bs->opaque; 272 273 /* 274 * blkverify quits the whole qemu process if there is a mismatch 275 * between bs->file->bs and s->test_file->bs. Therefore, we know 276 * know that both must match bs and we can recurse down to either. 277 */ 278 return bdrv_recurse_can_replace(bs->file->bs, to_replace) || 279 bdrv_recurse_can_replace(s->test_file->bs, to_replace); 280} 281 282static void blkverify_refresh_filename(BlockDriverState *bs) 283{ 284 BDRVBlkverifyState *s = bs->opaque; 285 286 if (bs->file->bs->exact_filename[0] 287 && s->test_file->bs->exact_filename[0]) 288 { 289 int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename), 290 "blkverify:%s:%s", 291 bs->file->bs->exact_filename, 292 s->test_file->bs->exact_filename); 293 if (ret >= sizeof(bs->exact_filename)) { 294 /* An overflow makes the filename unusable, so do not report any */ 295 bs->exact_filename[0] = 0; 296 } 297 } 298} 299 300static char *blkverify_dirname(BlockDriverState *bs, Error **errp) 301{ 302 /* In general, there are two BDSs with different dirnames below this one; 303 * so there is no unique dirname we could return (unless both are equal by 304 * chance). Therefore, to be consistent, just always return NULL. */ 305 error_setg(errp, "Cannot generate a base directory for blkverify nodes"); 306 return NULL; 307} 308 309static BlockDriver bdrv_blkverify = { 310 .format_name = "blkverify", 311 .protocol_name = "blkverify", 312 .instance_size = sizeof(BDRVBlkverifyState), 313 314 .bdrv_parse_filename = blkverify_parse_filename, 315 .bdrv_file_open = blkverify_open, 316 .bdrv_close = blkverify_close, 317 .bdrv_child_perm = bdrv_default_perms, 318 .bdrv_getlength = blkverify_getlength, 319 .bdrv_refresh_filename = blkverify_refresh_filename, 320 .bdrv_dirname = blkverify_dirname, 321 322 .bdrv_co_preadv = blkverify_co_preadv, 323 .bdrv_co_pwritev = blkverify_co_pwritev, 324 .bdrv_co_flush = blkverify_co_flush, 325 326 .is_filter = true, 327 .bdrv_recurse_can_replace = blkverify_recurse_can_replace, 328}; 329 330static void bdrv_blkverify_init(void) 331{ 332 bdrv_register(&bdrv_blkverify); 333} 334 335block_init(bdrv_blkverify_init);