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qcow2: Split qcow2_check_refcounts()

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Put the code for calculating the reference counts and comparing them
during qemu-img check into own functions.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Max Reitz 2014-10-22 14:09:30 +02:00 committed by Kevin Wolf
parent 5b84106bd9
commit 6ca56bf5e9
1 changed files with 102 additions and 51 deletions
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153
block/qcow2-refcount.c
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@ -1535,71 +1535,70 @@ done:
return new_offset;
}
static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res,
BdrvCheckMode fix, uint16_t **refcount_table,
int64_t *nb_clusters);
/*
* 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 occurred.
* Calculates an in-memory refcount table.
*/
int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
BdrvCheckMode fix)
static int calculate_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
BdrvCheckMode fix, uint16_t **refcount_table,
int64_t *nb_clusters)
{
BDRVQcowState *s = bs->opaque;
int64_t size, i, highest_cluster, nb_clusters;
int refcount1, refcount2;
int64_t i;
QCowSnapshot *sn;
uint16_t *refcount_table;
int ret;
size = bdrv_getlength(bs->file);
if (size < 0) {
res->check_errors++;
return size;
}
nb_clusters = size_to_clusters(s, size);
if (nb_clusters > INT_MAX) {
res->check_errors++;
return -EFBIG;
}
refcount_table = g_try_new0(uint16_t, nb_clusters);
if (nb_clusters && refcount_table == NULL) {
*refcount_table = g_try_new0(uint16_t, *nb_clusters);
if (*nb_clusters && *refcount_table == NULL) {
res->check_errors++;
return -ENOMEM;
}
res->bfi.total_clusters =
size_to_clusters(s, bs->total_sectors * BDRV_SECTOR_SIZE);
/* header */
inc_refcounts(bs, res, refcount_table, nb_clusters,
inc_refcounts(bs, res, *refcount_table, *nb_clusters,
0, s->cluster_size);
/* current L1 table */
ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
ret = check_refcounts_l1(bs, res, *refcount_table, *nb_clusters,
s->l1_table_offset, s->l1_size, CHECK_FRAG_INFO);
if (ret < 0) {
goto fail;
return ret;
}
/* snapshots */
for(i = 0; i < s->nb_snapshots; i++) {
for (i = 0; i < s->nb_snapshots; i++) {
sn = s->snapshots + i;
ret = check_refcounts_l1(bs, res, 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) {
goto fail;
return ret;
}
}
inc_refcounts(bs, res, refcount_table, nb_clusters,
inc_refcounts(bs, res, *refcount_table, *nb_clusters,
s->snapshots_offset, s->snapshots_size);
/* refcount data */
inc_refcounts(bs, res, refcount_table, nb_clusters,
inc_refcounts(bs, res, *refcount_table, *nb_clusters,
s->refcount_table_offset,
s->refcount_table_size * sizeof(uint64_t));
return check_refblocks(bs, res, fix, refcount_table, nb_clusters);
}
/*
* Checks consistency of refblocks and accounts for each refblock in
* *refcount_table.
*/
static int check_refblocks(BlockDriverState *bs, BdrvCheckResult *res,
BdrvCheckMode fix, uint16_t **refcount_table,
int64_t *nb_clusters)
{
BDRVQcowState *s = bs->opaque;
int64_t i;
for(i = 0; i < s->refcount_table_size; i++) {
uint64_t offset, cluster;
offset = s->refcount_table[i];
@ -1613,7 +1612,7 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
continue;
}
if (cluster >= nb_clusters) {
if (cluster >= *nb_clusters) {
fprintf(stderr, "ERROR refcount block %" PRId64
" is outside image\n", i);
res->corruptions++;
@ -1621,14 +1620,14 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
}
if (offset != 0) {
inc_refcounts(bs, res, refcount_table, nb_clusters,
inc_refcounts(bs, res, *refcount_table, *nb_clusters,
offset, s->cluster_size);
if (refcount_table[cluster] != 1) {
if ((*refcount_table)[cluster] != 1) {
fprintf(stderr, "%s refcount block %" PRId64
" refcount=%d\n",
fix & BDRV_FIX_ERRORS ? "Repairing" :
"ERROR",
i, refcount_table[cluster]);
i, (*refcount_table)[cluster]);
if (fix & BDRV_FIX_ERRORS) {
int64_t new_offset;
@ -1640,17 +1639,18 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
}
/* update refcounts */
if ((new_offset >> s->cluster_bits) >= nb_clusters) {
if ((new_offset >> s->cluster_bits) >= *nb_clusters) {
/* increase refcount_table size if necessary */
int old_nb_clusters = nb_clusters;
nb_clusters = (new_offset >> s->cluster_bits) + 1;
refcount_table = g_renew(uint16_t, refcount_table,
nb_clusters);
memset(&refcount_table[old_nb_clusters], 0, (nb_clusters
- old_nb_clusters) * sizeof(uint16_t));
int old_nb_clusters = *nb_clusters;
*nb_clusters = (new_offset >> s->cluster_bits) + 1;
*refcount_table = g_renew(uint16_t, *refcount_table,
*nb_clusters);
memset(&(*refcount_table)[old_nb_clusters], 0,
(*nb_clusters - old_nb_clusters) *
sizeof(uint16_t));
}
refcount_table[cluster]--;
inc_refcounts(bs, res, refcount_table, nb_clusters,
(*refcount_table)[cluster]--;
inc_refcounts(bs, res, *refcount_table, *nb_clusters,
new_offset, s->cluster_size);
res->corruptions_fixed++;
@ -1661,8 +1661,22 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
}
}
/* compare ref counts */
for (i = 0, highest_cluster = 0; i < nb_clusters; i++) {
return 0;
}
/*
* Compares the actual reference count for each cluster in the image against the
* refcount as reported by the refcount structures on-disk.
*/
static void compare_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
BdrvCheckMode fix, int64_t *highest_cluster,
uint16_t *refcount_table, int64_t nb_clusters)
{
BDRVQcowState *s = bs->opaque;
int64_t i;
int refcount1, refcount2, ret;
for (i = 0, *highest_cluster = 0; i < nb_clusters; i++) {
refcount1 = get_refcount(bs, i);
if (refcount1 < 0) {
fprintf(stderr, "Can't get refcount for cluster %" PRId64 ": %s\n",
@ -1674,11 +1688,10 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
refcount2 = refcount_table[i];
if (refcount1 > 0 || refcount2 > 0) {
highest_cluster = i;
*highest_cluster = i;
}
if (refcount1 != refcount2) {
/* Check if we're allowed to fix the mismatch */
int *num_fixed = NULL;
if (refcount1 > refcount2 && (fix & BDRV_FIX_LEAKS)) {
@ -1711,6 +1724,44 @@ int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
}
}
}
}
/*
* 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 occurred.
*/
int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
BdrvCheckMode fix)
{
BDRVQcowState *s = bs->opaque;
int64_t size, highest_cluster, nb_clusters;
uint16_t *refcount_table;
int ret;
size = bdrv_getlength(bs->file);
if (size < 0) {
res->check_errors++;
return size;
}
nb_clusters = size_to_clusters(s, size);
if (nb_clusters > INT_MAX) {
res->check_errors++;
return -EFBIG;
}
res->bfi.total_clusters =
size_to_clusters(s, bs->total_sectors * BDRV_SECTOR_SIZE);
ret = calculate_refcounts(bs, res, fix, &refcount_table, &nb_clusters);
if (ret < 0) {
goto fail;
}
compare_refcounts(bs, res, fix, &highest_cluster, refcount_table,
nb_clusters);
/* check OFLAG_COPIED */
ret = check_oflag_copied(bs, res, fix);