}
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE);
- if (bdrv_pwrite(bs->file, s->refcount_block_cache_offset,
- s->refcount_block_cache, size) != size)
+ if (bdrv_pwrite_sync(bs->file, s->refcount_block_cache_offset,
+ s->refcount_block_cache, size) < 0)
{
return -EIO;
}
int ret;
if (cache_refcount_updates) {
- write_refcount_block(bs);
+ ret = write_refcount_block(bs);
+ if (ret < 0) {
+ return ret;
+ }
}
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_LOAD);
ret = bdrv_pread(bs->file, refcount_block_offset, s->refcount_block_cache,
s->cluster_size);
- if (ret != s->cluster_size)
- return -EIO;
+ if (ret < 0) {
+ return ret;
+ }
+
s->refcount_block_cache_offset = refcount_block_offset;
return 0;
}
+/*
+ * Returns the refcount of the cluster given by its index. Any non-negative
+ * return value is the refcount of the cluster, negative values are -errno
+ * and indicate an error.
+ */
static int get_refcount(BlockDriverState *bs, int64_t cluster_index)
{
BDRVQcowState *s = bs->opaque;
int refcount_table_index, block_index;
int64_t refcount_block_offset;
+ int ret;
refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
if (refcount_table_index >= s->refcount_table_size)
return 0;
if (refcount_block_offset != s->refcount_block_cache_offset) {
/* better than nothing: return allocated if read error */
- if (load_refcount_block(bs, refcount_block_offset) < 0)
- return 1;
+ ret = load_refcount_block(bs, refcount_block_offset);
+ if (ret < 0) {
+ return ret;
+ }
}
block_index = cluster_index &
((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
}
/* Allocate the refcount block itself and mark it as used */
- uint64_t new_block = alloc_clusters_noref(bs, s->cluster_size);
- memset(s->refcount_block_cache, 0, s->cluster_size);
- s->refcount_block_cache_offset = new_block;
+ int64_t new_block = alloc_clusters_noref(bs, s->cluster_size);
+ if (new_block < 0) {
+ return new_block;
+ }
#ifdef DEBUG_ALLOC2
fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64
#endif
if (in_same_refcount_block(s, new_block, cluster_index << s->cluster_bits)) {
+ /* Zero the new refcount block before updating it */
+ memset(s->refcount_block_cache, 0, s->cluster_size);
+ s->refcount_block_cache_offset = new_block;
+
/* The block describes itself, need to update the cache */
int block_index = (new_block >> s->cluster_bits) &
((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
if (ret < 0) {
goto fail_block;
}
+
+ /* Initialize the new refcount block only after updating its refcount,
+ * update_refcount uses the refcount cache itself */
+ memset(s->refcount_block_cache, 0, s->cluster_size);
+ s->refcount_block_cache_offset = new_block;
}
/* Now the new refcount block needs to be written to disk */
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE);
- ret = bdrv_pwrite(bs->file, new_block, s->refcount_block_cache,
+ ret = bdrv_pwrite_sync(bs->file, new_block, s->refcount_block_cache,
s->cluster_size);
if (ret < 0) {
goto fail_block;
if (refcount_table_index < s->refcount_table_size) {
uint64_t data64 = cpu_to_be64(new_block);
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP);
- ret = bdrv_pwrite(bs->file,
+ ret = bdrv_pwrite_sync(bs->file,
s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
&data64, sizeof(data64));
if (ret < 0) {
/* Write refcount blocks to disk */
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS);
- ret = bdrv_pwrite(bs->file, meta_offset, new_blocks,
+ ret = bdrv_pwrite_sync(bs->file, meta_offset, new_blocks,
blocks_clusters * s->cluster_size);
qemu_free(new_blocks);
if (ret < 0) {
}
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE);
- ret = bdrv_pwrite(bs->file, table_offset, new_table,
+ ret = bdrv_pwrite_sync(bs->file, table_offset, new_table,
table_size * sizeof(uint64_t));
if (ret < 0) {
goto fail_table;
cpu_to_be64w((uint64_t*)data, table_offset);
cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE);
- ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, refcount_table_offset),
+ ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, refcount_table_offset),
data, sizeof(data));
if (ret < 0) {
goto fail_table;
{
BDRVQcowState *s = bs->opaque;
size_t size;
+ int ret;
if (cache_refcount_updates) {
return 0;
}
+ if (first_index < 0) {
+ return 0;
+ }
+
first_index &= ~(REFCOUNTS_PER_SECTOR - 1);
last_index = (last_index + REFCOUNTS_PER_SECTOR)
& ~(REFCOUNTS_PER_SECTOR - 1);
size = (last_index - first_index) << REFCOUNT_SHIFT;
+
BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART);
- if (bdrv_pwrite(bs->file,
+ ret = bdrv_pwrite_sync(bs->file,
refcount_block_offset + (first_index << REFCOUNT_SHIFT),
- &s->refcount_block_cache[first_index], size) != size)
- {
- return -EIO;
+ &s->refcount_block_cache[first_index], size);
+ if (ret < 0) {
+ return ret;
}
return 0;
table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
if ((old_table_index >= 0) && (table_index != old_table_index)) {
- if (write_refcount_block_entries(bs, refcount_block_offset,
- first_index, last_index) < 0)
- {
- return -EIO;
+ ret = write_refcount_block_entries(bs, refcount_block_offset,
+ first_index, last_index);
+ if (ret < 0) {
+ return ret;
}
first_index = -1;
/* Write last changed block to disk */
if (refcount_block_offset != 0) {
- if (write_refcount_block_entries(bs, refcount_block_offset,
- first_index, last_index) < 0)
- {
- return ret < 0 ? ret : -EIO;
+ int wret;
+ wret = write_refcount_block_entries(bs, refcount_block_offset,
+ first_index, last_index);
+ if (wret < 0) {
+ return ret < 0 ? ret : wret;
}
}
return ret;
}
-/* addend must be 1 or -1 */
+/*
+ * Increases or decreases the refcount of a given cluster by one.
+ * addend must be 1 or -1.
+ *
+ * If the return value is non-negative, it is the new refcount of the cluster.
+ * If it is negative, it is -errno and indicates an error.
+ */
static int update_cluster_refcount(BlockDriverState *bs,
int64_t cluster_index,
int addend)
static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
{
BDRVQcowState *s = bs->opaque;
- int i, nb_clusters;
+ int i, nb_clusters, refcount;
nb_clusters = size_to_clusters(s, size);
retry:
for(i = 0; i < nb_clusters; i++) {
int64_t next_cluster_index = s->free_cluster_index++;
- if (get_refcount(bs, next_cluster_index) != 0)
+ refcount = get_refcount(bs, next_cluster_index);
+
+ if (refcount < 0) {
+ return refcount;
+ } else if (refcount != 0) {
goto retry;
+ }
}
#ifdef DEBUG_ALLOC2
printf("alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n",
BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC);
offset = alloc_clusters_noref(bs, size);
+ if (offset < 0) {
+ return offset;
+ }
+
ret = update_refcount(bs, offset, size, 1);
if (ret < 0) {
return ret;
ret = update_refcount(bs, offset, size, -1);
if (ret < 0) {
fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
- abort();
+ /* TODO Remember the clusters to free them later and avoid leaking */
}
}
} else {
refcount = get_refcount(bs, offset >> s->cluster_bits);
}
+
+ if (refcount < 0) {
+ goto fail;
+ }
}
if (refcount == 1) {
}
}
if (l2_modified) {
- if (bdrv_pwrite(bs->file,
- l2_offset, l2_table, l2_size) != l2_size)
+ if (bdrv_pwrite_sync(bs->file,
+ l2_offset, l2_table, l2_size) < 0)
goto fail;
}
} else {
refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
}
- if (refcount == 1) {
+ if (refcount < 0) {
+ goto fail;
+ } else if (refcount == 1) {
l2_offset |= QCOW_OFLAG_COPIED;
}
if (l2_offset != old_l2_offset) {
if (l1_modified) {
for(i = 0; i < l1_size; i++)
cpu_to_be64s(&l1_table[i]);
- if (bdrv_pwrite(bs->file, l1_table_offset, l1_table,
- l1_size2) != l1_size2)
+ if (bdrv_pwrite_sync(bs->file, l1_table_offset, l1_table,
+ l1_size2) < 0)
goto fail;
for(i = 0; i < l1_size; i++)
be64_to_cpus(&l1_table[i]);
* 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)
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;
}
/*
* 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);
"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,
- offset & ~511, nb_csectors * 512);
+ inc_refcounts(bs, res, refcount_table, refcount_table_size,
+ offset & ~511, nb_csectors * 512);
} else {
/* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
if (check_copied) {
uint64_t entry = offset;
offset &= ~QCOW_OFLAG_COPIED;
refcount = get_refcount(bs, offset >> s->cluster_bits);
+ 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,
- offset, s->cluster_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;
}
* 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,
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,
- l1_table_offset, l1_size2);
+ inc_refcounts(bs, res, refcount_table, refcount_table_size,
+ l1_table_offset, l1_size2);
/* Read L1 table entries from disk */
if (l1_size2 == 0) {
if (check_copied) {
refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED)
>> s->cluster_bits);
+ 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;
}
* 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,
- 0, s->cluster_size);
+ 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,
- sn->l1_table_offset, sn->l1_size, 0);
+ 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,
- s->snapshots_offset, s->snapshots_size);
+ inc_refcounts(bs, res, refcount_table, nb_clusters,
+ s->snapshots_offset, s->snapshots_size);
/* refcount data */
- errors += inc_refcounts(bs, refcount_table, nb_clusters,
- s->refcount_table_offset,
- s->refcount_table_size * sizeof(uint64_t));
+ 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++) {
- int64_t offset;
+ uint64_t offset, cluster;
offset = s->refcount_table[i];
+ cluster = offset >> s->cluster_bits;
/* Refcount blocks are cluster aligned */
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);
+ res->corruptions++;
+ continue;
}
if (offset != 0) {
- errors += inc_refcounts(bs, refcount_table, nb_clusters,
- offset, s->cluster_size);
- if (refcount_table[offset / s->cluster_size] != 1) {
+ 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[offset / s->cluster_size]);
+ i, refcount_table[cluster]);
+ res->corruptions++;
}
}
}
/* compare ref counts */
for(i = 0; i < nb_clusters; i++) {
refcount1 = get_refcount(bs, i);
+ 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;
}
projects / qemu.git / blobdiff