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_str(options, "x-image", 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_str(options, "x-image", 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     qemu_opts_del(opts);
 146     return ret;
 147 }
 148
 149 static void blkverify_close(BlockDriverState *bs)
 150 {
 151     BDRVBlkverifyState *s = bs->opaque;
 152
 153     bdrv_unref_child(bs, s->test_file);
 154     s->test_file = NULL;
 155 }
 156
 157 static int64_t blkverify_getlength(BlockDriverState *bs)
 158 {
 159     BDRVBlkverifyState *s = bs->opaque;
 160
 161     return bdrv_getlength(s->test_file->bs);
 162 }
 163
 164 static void coroutine_fn blkverify_do_test_req(void *opaque)
 165 {
 166     BlkverifyRequest *r = opaque;
 167     BDRVBlkverifyState *s = r->bs->opaque;
 168
 169     r->ret = r->request_fn(s->test_file, r->offset, r->bytes, r->qiov,
 170                            r->flags);
 171     r->done++;
 172     qemu_coroutine_enter_if_inactive(r->co);
 173 }
 174
 175 static void coroutine_fn blkverify_do_raw_req(void *opaque)
 176 {
 177     BlkverifyRequest *r = opaque;
 178
 179     r->raw_ret = r->request_fn(r->bs->file, r->offset, r->bytes, r->raw_qiov,
 180                                r->flags);
 181     r->done++;
 182     qemu_coroutine_enter_if_inactive(r->co);
 183 }
 184
 185 static int coroutine_fn
 186 blkverify_co_prwv(BlockDriverState *bs, BlkverifyRequest *r, uint64_t offset,
 187                   uint64_t bytes, QEMUIOVector *qiov, QEMUIOVector *raw_qiov,
 188                   int flags, bool is_write)
 189 {
 190     Coroutine *co_a, *co_b;
 191
 192     *r = (BlkverifyRequest) {
 193         .co         = qemu_coroutine_self(),
 194         .bs         = bs,
 195         .offset     = offset,
 196         .bytes      = bytes,
 197         .qiov       = qiov,
 198         .raw_qiov   = raw_qiov,
 199         .flags      = flags,
 200         .is_write   = is_write,
 201         .request_fn = is_write ? bdrv_co_pwritev : bdrv_co_preadv,
 202     };
 203
 204     co_a = qemu_coroutine_create(blkverify_do_test_req, r);
 205     co_b = qemu_coroutine_create(blkverify_do_raw_req, r);
 206
 207     qemu_coroutine_enter(co_a);
 208     qemu_coroutine_enter(co_b);
 209
 210     while (r->done < 2) {
 211         qemu_coroutine_yield();
 212     }
 213
 214     if (r->ret != r->raw_ret) {
 215         blkverify_err(r, "return value mismatch %d != %d", r->ret, r->raw_ret);
 216     }
 217
 218     return r->ret;
 219 }
 220
 221 static int coroutine_fn
 222 blkverify_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
 223                     QEMUIOVector *qiov, int flags)
 224 {
 225     BlkverifyRequest r;
 226     QEMUIOVector raw_qiov;
 227     void *buf;
 228     ssize_t cmp_offset;
 229     int ret;
 230
 231     buf = qemu_blockalign(bs->file->bs, qiov->size);
 232     qemu_iovec_init(&raw_qiov, qiov->niov);
 233     qemu_iovec_clone(&raw_qiov, qiov, buf);
 234
 235     ret = blkverify_co_prwv(bs, &r, offset, bytes, qiov, &raw_qiov, flags,
 236                             false);
 237
 238     cmp_offset = qemu_iovec_compare(qiov, &raw_qiov);
 239     if (cmp_offset != -1) {
 240         blkverify_err(&r, "contents mismatch at offset %" PRId64,
 241                       offset + cmp_offset);
 242     }
 243
 244     qemu_iovec_destroy(&raw_qiov);
 245     qemu_vfree(buf);
 246
 247     return ret;
 248 }
 249
 250 static int coroutine_fn
 251 blkverify_co_pwritev(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
 252                      QEMUIOVector *qiov, int flags)
 253 {
 254     BlkverifyRequest r;
 255     return blkverify_co_prwv(bs, &r, offset, bytes, qiov, qiov, flags, true);
 256 }
 257
 258 static int blkverify_co_flush(BlockDriverState *bs)
 259 {
 260     BDRVBlkverifyState *s = bs->opaque;
 261
 262     /* Only flush test file, the raw file is not important */
 263     return bdrv_co_flush(s->test_file->bs);
 264 }
 265
 266 static bool blkverify_recurse_is_first_non_filter(BlockDriverState *bs,
 267                                                   BlockDriverState *candidate)
 268 {
 269     BDRVBlkverifyState *s = bs->opaque;
 270
 271     bool perm = bdrv_recurse_is_first_non_filter(bs->file->bs, candidate);
 272
 273     if (perm) {
 274         return true;
 275     }
 276
 277     return bdrv_recurse_is_first_non_filter(s->test_file->bs, candidate);
 278 }
 279
 280 static void blkverify_refresh_filename(BlockDriverState *bs, QDict *options)
 281 {
 282     BDRVBlkverifyState *s = bs->opaque;
 283
 284     /* bs->file->bs has already been refreshed */
 285     bdrv_refresh_filename(s->test_file->bs);
 286
 287     if (bs->file->bs->full_open_options
 288         && s->test_file->bs->full_open_options)
 289     {
 290         QDict *opts = qdict_new();
 291         qdict_put_str(opts, "driver", "blkverify");
 292
 293         QINCREF(bs->file->bs->full_open_options);
 294         qdict_put(opts, "raw", bs->file->bs->full_open_options);
 295         QINCREF(s->test_file->bs->full_open_options);
 296         qdict_put(opts, "test", s->test_file->bs->full_open_options);
 297
 298         bs->full_open_options = opts;
 299     }
 300
 301     if (bs->file->bs->exact_filename[0]
 302         && s->test_file->bs->exact_filename[0])
 303     {
 304         int ret = snprintf(bs->exact_filename, sizeof(bs->exact_filename),
 305                            "blkverify:%s:%s",
 306                            bs->file->bs->exact_filename,
 307                            s->test_file->bs->exact_filename);
 308         if (ret >= sizeof(bs->exact_filename)) {
 309             /* An overflow makes the filename unusable, so do not report any */
 310             bs->exact_filename[0] = 0;
 311         }
 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);