diff options
| -rw-r--r-- | block-qcow2.c | 71 | ||||
| -rw-r--r-- | block.c | 14 | ||||
| -rw-r--r-- | block.h | 1 | ||||
| -rw-r--r-- | block_int.h | 3 |
4 files changed, 70 insertions, 19 deletions
diff --git a/block-qcow2.c b/block-qcow2.c index 231b12f0e4..cbadcd0cb3 100644 --- a/block-qcow2.c +++ b/block-qcow2.c @@ -177,9 +177,7 @@ static int64_t alloc_clusters(BlockDriverState *bs, int64_t size); static int64_t alloc_bytes(BlockDriverState *bs, int size); static void free_clusters(BlockDriverState *bs, int64_t offset, int64_t size); -#ifdef DEBUG_ALLOC -static void check_refcounts(BlockDriverState *bs); -#endif +static int check_refcounts(BlockDriverState *bs); static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename) { @@ -2564,8 +2562,14 @@ static void update_refcount(BlockDriverState *bs, } } -#ifdef DEBUG_ALLOC -static void inc_refcounts(BlockDriverState *bs, +/* + * Increases the refcount for a range of clusters in a given refcount table. + * This is used to construct a temporary refcount table out of L1 and L2 tables + * which can be compared the the refcount table saved in the image. + * + * Returns the number of errors in the image that were found + */ +static int inc_refcounts(BlockDriverState *bs, uint16_t *refcount_table, int refcount_table_size, int64_t offset, int64_t size) @@ -2573,9 +2577,10 @@ static void inc_refcounts(BlockDriverState *bs, BDRVQcowState *s = bs->opaque; int64_t start, last, cluster_offset; int k; + int errors = 0; if (size <= 0) - return; + return 0; start = offset & ~(s->cluster_size - 1); last = (offset + size - 1) & ~(s->cluster_size - 1); @@ -2585,13 +2590,17 @@ static void inc_refcounts(BlockDriverState *bs, if (k < 0 || k >= refcount_table_size) { fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n", cluster_offset); + errors++; } else { if (++refcount_table[k] == 0) { fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64 "\n", cluster_offset); + errors++; } } } + + return errors; } static int check_refcounts_l1(BlockDriverState *bs, @@ -2603,11 +2612,12 @@ static int check_refcounts_l1(BlockDriverState *bs, BDRVQcowState *s = bs->opaque; uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2; int l2_size, i, j, nb_csectors, refcount; + int errors = 0; l2_table = NULL; l1_size2 = l1_size * sizeof(uint64_t); - inc_refcounts(bs, refcount_table, refcount_table_size, + errors += inc_refcounts(bs, refcount_table, refcount_table_size, l1_table_offset, l1_size2); l1_table = qemu_malloc(l1_size2); @@ -2627,6 +2637,7 @@ static int check_refcounts_l1(BlockDriverState *bs, if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) { fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64 " refcount=%d\n", l2_offset, refcount); + errors++; } } l2_offset &= ~QCOW_OFLAG_COPIED; @@ -2641,11 +2652,12 @@ static int check_refcounts_l1(BlockDriverState *bs, "copied flag must never be set for compressed " "clusters\n", offset >> s->cluster_bits); offset &= ~QCOW_OFLAG_COPIED; + errors++; } nb_csectors = ((offset >> s->csize_shift) & s->csize_mask) + 1; offset &= s->cluster_offset_mask; - inc_refcounts(bs, refcount_table, + errors += inc_refcounts(bs, refcount_table, refcount_table_size, offset & ~511, nb_csectors * 512); } else { @@ -2654,16 +2666,17 @@ static int check_refcounts_l1(BlockDriverState *bs, if ((refcount == 1) != ((offset & QCOW_OFLAG_COPIED) != 0)) { fprintf(stderr, "ERROR OFLAG_COPIED: offset=%" PRIx64 " refcount=%d\n", offset, refcount); + errors++; } } offset &= ~QCOW_OFLAG_COPIED; - inc_refcounts(bs, refcount_table, + errors += inc_refcounts(bs, refcount_table, refcount_table_size, offset, s->cluster_size); } } } - inc_refcounts(bs, refcount_table, + errors += inc_refcounts(bs, refcount_table, refcount_table_size, l2_offset, s->cluster_size); @@ -2671,7 +2684,7 @@ static int check_refcounts_l1(BlockDriverState *bs, } qemu_free(l1_table); qemu_free(l2_table); - return 0; + return errors; fail: fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n"); qemu_free(l1_table); @@ -2679,24 +2692,35 @@ static int check_refcounts_l1(BlockDriverState *bs, return -EIO; } -static void check_refcounts(BlockDriverState *bs) +/* + * Checks an image for refcount consistency. + * + * Returns 0 if no errors are found, the number of errors in case the image is + * detected as corrupted, and -errno when an internal error occured. + */ +static int check_refcounts(BlockDriverState *bs) { BDRVQcowState *s = bs->opaque; int64_t size; int nb_clusters, refcount1, refcount2, i; QCowSnapshot *sn; uint16_t *refcount_table; + int ret, errors = 0; size = bdrv_getlength(s->hd); nb_clusters = size_to_clusters(s, size); refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t)); /* header */ - inc_refcounts(bs, refcount_table, nb_clusters, + errors += inc_refcounts(bs, refcount_table, nb_clusters, 0, s->cluster_size); - check_refcounts_l1(bs, refcount_table, nb_clusters, + ret = check_refcounts_l1(bs, refcount_table, nb_clusters, s->l1_table_offset, s->l1_size, 1); + if (ret < 0) { + return ret; + } + errors += ret; /* snapshots */ for(i = 0; i < s->nb_snapshots; i++) { @@ -2704,18 +2728,18 @@ static void check_refcounts(BlockDriverState *bs) check_refcounts_l1(bs, refcount_table, nb_clusters, sn->l1_table_offset, sn->l1_size, 0); } - inc_refcounts(bs, refcount_table, nb_clusters, + errors += inc_refcounts(bs, refcount_table, nb_clusters, s->snapshots_offset, s->snapshots_size); /* refcount data */ - inc_refcounts(bs, refcount_table, nb_clusters, + errors += inc_refcounts(bs, refcount_table, nb_clusters, s->refcount_table_offset, s->refcount_table_size * sizeof(uint64_t)); for(i = 0; i < s->refcount_table_size; i++) { int64_t offset; offset = s->refcount_table[i]; if (offset != 0) { - inc_refcounts(bs, refcount_table, nb_clusters, + errors += inc_refcounts(bs, refcount_table, nb_clusters, offset, s->cluster_size); } } @@ -2724,12 +2748,21 @@ static void check_refcounts(BlockDriverState *bs) for(i = 0; i < nb_clusters; i++) { refcount1 = get_refcount(bs, i); refcount2 = refcount_table[i]; - if (refcount1 != refcount2) + if (refcount1 != refcount2) { fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n", i, refcount1, refcount2); + errors++; + } } qemu_free(refcount_table); + + return errors; +} + +static int qcow_check(BlockDriverState *bs) +{ + return check_refcounts(bs); } #if 0 @@ -2751,7 +2784,6 @@ static void dump_refcounts(BlockDriverState *bs) } } #endif -#endif static int qcow_put_buffer(BlockDriverState *bs, const uint8_t *buf, int64_t pos, int size) @@ -2806,4 +2838,5 @@ BlockDriver bdrv_qcow2 = { .bdrv_get_buffer = qcow_get_buffer, .bdrv_create2 = qcow_create2, + .bdrv_check = qcow_check, }; @@ -506,6 +506,20 @@ void bdrv_delete(BlockDriverState *bs) qemu_free(bs); } +/* + * Run consistency checks on an image + * + * Returns the number of errors or -errno when an internal error occurs + */ +int bdrv_check(BlockDriverState *bs) +{ + if (bs->drv->bdrv_check == NULL) { + return -ENOTSUP; + } + + return bs->drv->bdrv_check(bs); +} + /* commit COW file into the raw image */ int bdrv_commit(BlockDriverState *bs) { @@ -73,6 +73,7 @@ int bdrv_open(BlockDriverState *bs, const char *filename, int flags); int bdrv_open2(BlockDriverState *bs, const char *filename, int flags, BlockDriver *drv); void bdrv_close(BlockDriverState *bs); +int bdrv_check(BlockDriverState *bs); int bdrv_read(BlockDriverState *bs, int64_t sector_num, uint8_t *buf, int nb_sectors); int bdrv_write(BlockDriverState *bs, int64_t sector_num, diff --git a/block_int.h b/block_int.h index 3e78997c71..e10b9069f2 100644 --- a/block_int.h +++ b/block_int.h @@ -102,6 +102,9 @@ struct BlockDriver { const char *backing_file, const char *backing_format, int flags); + /* Returns number of errors in image, -errno for internal errors */ + int (*bdrv_check)(BlockDriverState* bs); + struct BlockDriver *next; }; |