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qcow2/vdi: Change check to distinguish error cases

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This distinguishes between harmless leaks and real corruption. Hopefully users
better understand what qemu-img check wants to tell them.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Kevin Wolf 2010-06-29 12:37:54 +02:00
parent e076f3383b
commit 9ac228e02c
6 changed files with 79 additions and 67 deletions
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3
block.c
View File

@ -721,8 +721,7 @@ int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res)
}
memset(res, 0, sizeof(*res));
res->corruptions = bs->drv->bdrv_check(bs);
return res->corruptions < 0 ? res->corruptions : 0;
return bs->drv->bdrv_check(bs, res);
}
/* commit COW file into the raw image */

102
block/qcow2-refcount.c
View File

@ -884,9 +884,10 @@ int qcow2_update_snapshot_refcount(BlockDriverState *bs,
* 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
* Modifies the number of errors in res.
*/
static int inc_refcounts(BlockDriverState *bs,
static void inc_refcounts(BlockDriverState *bs,
BdrvCheckResult *res,
uint16_t *refcount_table,
int refcount_table_size,
int64_t offset, int64_t size)
@ -894,30 +895,32 @@ static int inc_refcounts(BlockDriverState *bs,
BDRVQcowState *s = bs->opaque;
int64_t start, last, cluster_offset;
int k;
int errors = 0;
if (size <= 0)
return 0;
return;
start = offset & ~(s->cluster_size - 1);
last = (offset + size - 1) & ~(s->cluster_size - 1);
for(cluster_offset = start; cluster_offset <= last;
cluster_offset += s->cluster_size) {
k = cluster_offset >> s->cluster_bits;
if (k < 0 || k >= refcount_table_size) {
if (k < 0) {
fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n",
cluster_offset);
errors++;
res->corruptions++;
} else if (k >= refcount_table_size) {
fprintf(stderr, "Warning: cluster offset=0x%" PRIx64 " is after "
"the end of the image file, can't properly check refcounts.\n",
cluster_offset);
res->check_errors++;
} else {
if (++refcount_table[k] == 0) {
fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
"\n", cluster_offset);
errors++;
res->corruptions++;
}
}
}
return errors;
}
/*
@ -928,14 +931,13 @@ static int inc_refcounts(BlockDriverState *bs,
* Returns the number of errors found by the checks or -errno if an internal
* error occurred.
*/
static int check_refcounts_l2(BlockDriverState *bs,
static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
int check_copied)
{
BDRVQcowState *s = bs->opaque;
uint64_t *l2_table, offset;
int i, l2_size, nb_csectors, refcount;
int errors = 0;
/* Read L2 table from disk */
l2_size = s->l2_size * sizeof(uint64_t);
@ -955,15 +957,14 @@ static int check_refcounts_l2(BlockDriverState *bs,
"copied flag must never be set for compressed "
"clusters\n", offset >> s->cluster_bits);
offset &= ~QCOW_OFLAG_COPIED;
errors++;
res->corruptions++;
}
/* Mark cluster as used */
nb_csectors = ((offset >> s->csize_shift) &
s->csize_mask) + 1;
offset &= s->cluster_offset_mask;
errors += inc_refcounts(bs, refcount_table,
refcount_table_size,
inc_refcounts(bs, res, refcount_table, refcount_table_size,
offset & ~511, nb_csectors * 512);
} else {
/* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
@ -974,35 +975,35 @@ static int check_refcounts_l2(BlockDriverState *bs,
if (refcount < 0) {
fprintf(stderr, "Can't get refcount for offset %"
PRIx64 ": %s\n", entry, strerror(-refcount));
goto fail;
}
if ((refcount == 1) != ((entry & QCOW_OFLAG_COPIED) != 0)) {
fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
PRIx64 " refcount=%d\n", entry, refcount);
errors++;
res->corruptions++;
}
}
/* Mark cluster as used */
offset &= ~QCOW_OFLAG_COPIED;
errors += inc_refcounts(bs, refcount_table,
refcount_table_size,
inc_refcounts(bs, res, refcount_table,refcount_table_size,
offset, s->cluster_size);
/* Correct offsets are cluster aligned */
if (offset & (s->cluster_size - 1)) {
fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not "
"properly aligned; L2 entry corrupted.\n", offset);
errors++;
res->corruptions++;
}
}
}
}
qemu_free(l2_table);
return errors;
return 0;
fail:
fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
fprintf(stderr, "ERROR: I/O error in check_refcounts_l2\n");
qemu_free(l2_table);
return -EIO;
}
@ -1016,6 +1017,7 @@ fail:
* error occurred.
*/
static int check_refcounts_l1(BlockDriverState *bs,
BdrvCheckResult *res,
uint16_t *refcount_table,
int refcount_table_size,
int64_t l1_table_offset, int l1_size,
@ -1024,12 +1026,11 @@ static int check_refcounts_l1(BlockDriverState *bs,
BDRVQcowState *s = bs->opaque;
uint64_t *l1_table, l2_offset, l1_size2;
int i, refcount, ret;
int errors = 0;
l1_size2 = l1_size * sizeof(uint64_t);
/* Mark L1 table as used */
errors += inc_refcounts(bs, refcount_table, refcount_table_size,
inc_refcounts(bs, res, refcount_table, refcount_table_size,
l1_table_offset, l1_size2);
/* Read L1 table entries from disk */
@ -1055,42 +1056,41 @@ static int check_refcounts_l1(BlockDriverState *bs,
if (refcount < 0) {
fprintf(stderr, "Can't get refcount for l2_offset %"
PRIx64 ": %s\n", l2_offset, strerror(-refcount));
goto fail;
}
if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) {
fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
" refcount=%d\n", l2_offset, refcount);
errors++;
res->corruptions++;
}
}
/* Mark L2 table as used */
l2_offset &= ~QCOW_OFLAG_COPIED;
errors += inc_refcounts(bs, refcount_table,
refcount_table_size,
l2_offset,
s->cluster_size);
inc_refcounts(bs, res, refcount_table, refcount_table_size,
l2_offset, s->cluster_size);
/* L2 tables are cluster aligned */
if (l2_offset & (s->cluster_size - 1)) {
fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not "
"cluster aligned; L1 entry corrupted\n", l2_offset);
errors++;
res->corruptions++;
}
/* Process and check L2 entries */
ret = check_refcounts_l2(bs, refcount_table, refcount_table_size,
l2_offset, check_copied);
ret = check_refcounts_l2(bs, res, refcount_table,
refcount_table_size, l2_offset, check_copied);
if (ret < 0) {
goto fail;
}
errors += ret;
}
}
qemu_free(l1_table);
return errors;
return 0;
fail:
fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
res->check_errors++;
qemu_free(l1_table);
return -EIO;
}
@ -1101,44 +1101,47 @@ fail:
* 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.
*/
int qcow2_check_refcounts(BlockDriverState *bs)
int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res)
{
BDRVQcowState *s = bs->opaque;
int64_t size;
int nb_clusters, refcount1, refcount2, i;
QCowSnapshot *sn;
uint16_t *refcount_table;
int ret, errors = 0;
int ret;
size = bdrv_getlength(bs->file);
nb_clusters = size_to_clusters(s, size);
refcount_table = qemu_mallocz(nb_clusters * sizeof(uint16_t));
/* header */
errors += inc_refcounts(bs, refcount_table, nb_clusters,
inc_refcounts(bs, res, refcount_table, nb_clusters,
0, s->cluster_size);
/* current L1 table */
ret = check_refcounts_l1(bs, refcount_table, nb_clusters,
ret = check_refcounts_l1(bs, res, 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++) {
sn = s->snapshots + i;
check_refcounts_l1(bs, refcount_table, nb_clusters,
ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
sn->l1_table_offset, sn->l1_size, 0);
if (ret < 0) {
return ret;
}
errors += inc_refcounts(bs, refcount_table, nb_clusters,
}
inc_refcounts(bs, res, refcount_table, nb_clusters,
s->snapshots_offset, s->snapshots_size);
/* refcount data */
errors += inc_refcounts(bs, refcount_table, nb_clusters,
inc_refcounts(bs, res, refcount_table, nb_clusters,
s->refcount_table_offset,
s->refcount_table_size * sizeof(uint64_t));
for(i = 0; i < s->refcount_table_size; i++) {
uint64_t offset, cluster;
offset = s->refcount_table[i];
@ -1148,22 +1151,23 @@ int qcow2_check_refcounts(BlockDriverState *bs)
if (offset & (s->cluster_size - 1)) {
fprintf(stderr, "ERROR refcount block %d is not "
"cluster aligned; refcount table entry corrupted\n", i);
errors++;
res->corruptions++;
continue;
}
if (cluster >= nb_clusters) {
fprintf(stderr, "ERROR refcount block %d is outside image\n", i);
errors++;
res->corruptions++;
continue;
}
if (offset != 0) {
errors += inc_refcounts(bs, refcount_table, nb_clusters,
inc_refcounts(bs, res, refcount_table, nb_clusters,
offset, s->cluster_size);
if (refcount_table[cluster] != 1) {
fprintf(stderr, "ERROR refcount block %d refcount=%d\n",
i, refcount_table[cluster]);
res->corruptions++;
}
}
}
@ -1174,19 +1178,25 @@ int qcow2_check_refcounts(BlockDriverState *bs)
if (refcount1 < 0) {
fprintf(stderr, "Can't get refcount for cluster %d: %s\n",
i, strerror(-refcount1));
res->check_errors++;
continue;
}
refcount2 = refcount_table[i];
if (refcount1 != refcount2) {
fprintf(stderr, "ERROR cluster %d refcount=%d reference=%d\n",
fprintf(stderr, "%s cluster %d refcount=%d reference=%d\n",
refcount1 < refcount2 ? "ERROR" : "Leaked",
i, refcount1, refcount2);
errors++;
if (refcount1 < refcount2) {
res->corruptions++;
} else {
res->leaks++;
}
}
}
qemu_free(refcount_table);
return errors;
return 0;
}

4
block/qcow2.c
View File

@ -1239,9 +1239,9 @@ static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
}
static int qcow_check(BlockDriverState *bs)
static int qcow_check(BlockDriverState *bs, BdrvCheckResult *result)
{
return qcow2_check_refcounts(bs);
return qcow2_check_refcounts(bs, result);
}
#if 0

2
block/qcow2.h
View File

@ -185,7 +185,7 @@ void qcow2_create_refcount_update(QCowCreateState *s, int64_t offset,
int qcow2_update_snapshot_refcount(BlockDriverState *bs,
int64_t l1_table_offset, int l1_size, int addend);
int qcow2_check_refcounts(BlockDriverState *bs);
int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res);
/* qcow2-cluster.c functions */
int qcow2_grow_l1_table(BlockDriverState *bs, int min_size);

10
block/vdi.c
View File

@ -291,11 +291,10 @@ static void vdi_header_print(VdiHeader *header)
}
#endif
static int vdi_check(BlockDriverState *bs)
static int vdi_check(BlockDriverState *bs, BdrvCheckResult *res)
{
/* TODO: additional checks possible. */
BDRVVdiState *s = (BDRVVdiState *)bs->opaque;
int n_errors = 0;
uint32_t blocks_allocated = 0;
uint32_t block;
uint32_t *bmap;
@ -315,11 +314,12 @@ static int vdi_check(BlockDriverState *bs)
} else {
fprintf(stderr, "ERROR: block index %" PRIu32
" also used by %" PRIu32 "\n", bmap[bmap_entry], bmap_entry);
res->corruptions++;
}
} else {
fprintf(stderr, "ERROR: block index %" PRIu32
" too large, is %" PRIu32 "\n", block, bmap_entry);
n_errors++;
res->corruptions++;
}
}
}
@ -327,12 +327,12 @@ static int vdi_check(BlockDriverState *bs)
fprintf(stderr, "ERROR: allocated blocks mismatch, is %" PRIu32
", should be %" PRIu32 "\n",
blocks_allocated, s->header.blocks_allocated);
n_errors++;
res->corruptions++;
}
qemu_free(bmap);
return n_errors;
return 0;
}
static int vdi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)

7
block_int.h
View File

@ -119,8 +119,11 @@ struct BlockDriver {
QEMUOptionParameter *create_options;
/* Returns number of errors in image, -errno for internal errors */
int (*bdrv_check)(BlockDriverState* bs);
/*
* Returns 0 for completed check, -errno for internal errors.
* The check results are stored in result.
*/
int (*bdrv_check)(BlockDriverState* bs, BdrvCheckResult *result);
void (*bdrv_debug_event)(BlockDriverState *bs, BlkDebugEvent event);