BDRVQcowState *s = bs->opaque;
int new_l1_size, new_l1_size2, ret, i;
uint64_t *new_l1_table;
- uint64_t new_l1_table_offset;
+ int64_t new_l1_table_offset;
uint8_t data[12];
new_l1_size = s->l1_size;
if (min_size <= new_l1_size)
return 0;
+ if (new_l1_size == 0) {
+ new_l1_size = 1;
+ }
while (min_size > new_l1_size) {
new_l1_size = (new_l1_size * 3 + 1) / 2;
}
/* write new table (align to cluster) */
new_l1_table_offset = qcow2_alloc_clusters(bs, new_l1_size2);
+ if (new_l1_table_offset < 0) {
+ qemu_free(new_l1_table);
+ return new_l1_table_offset;
+ }
for(i = 0; i < s->l1_size; i++)
new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
/* set new table */
cpu_to_be32w((uint32_t*)data, new_l1_size);
cpu_to_be64w((uint64_t*)(data + 4), new_l1_table_offset);
- if (bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,
- sizeof(data)) != sizeof(data))
+ ret = bdrv_pwrite(s->hd, offsetof(QCowHeader, l1_size), data,sizeof(data));
+ if (ret != sizeof(data)) {
goto fail;
+ }
qemu_free(s->l1_table);
qcow2_free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t));
s->l1_table_offset = new_l1_table_offset;
s->l1_size = new_l1_size;
return 0;
fail:
- qemu_free(s->l1_table);
- return -EIO;
+ qemu_free(new_l1_table);
+ qcow2_free_clusters(bs, new_l1_table_offset, new_l1_size2);
+ return ret < 0 ? ret : -EIO;
}
void qcow2_l2_cache_reset(BlockDriverState *bs)
/* allocate a new l2 entry */
l2_offset = qcow2_alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
+ if (l2_offset < 0) {
+ return NULL;
+ }
/* update the L1 entry */
return 0;
for (i = start; i < start + nb_clusters; i++)
- if (offset + i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
+ if (offset + (uint64_t) i * cluster_size != (be64_to_cpu(l2_table[i]) & ~mask))
break;
return (i - start);
int *num)
{
BDRVQcowState *s = bs->opaque;
- int l1_index, l2_index;
+ unsigned int l1_index, l2_index;
uint64_t l2_offset, *l2_table, cluster_offset;
int l1_bits, c;
- int index_in_cluster, nb_available, nb_needed, nb_clusters;
+ unsigned int index_in_cluster, nb_clusters;
+ uint64_t nb_available, nb_needed;
index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1);
nb_needed = *num + index_in_cluster;
* the end of the l1 entry
*/
- nb_available = (1 << l1_bits) - (offset & ((1 << l1_bits) - 1));
+ nb_available = (1ULL << l1_bits) - (offset & ((1ULL << l1_bits) - 1));
/* compute the number of available sectors */
* the l2 table offset in the qcow2 file and the cluster index
* in the l2 table are given to the caller.
*
+ * Returns 0 on success, -errno in failure case
*/
-
static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
uint64_t **new_l2_table,
uint64_t *new_l2_offset,
int *new_l2_index)
{
BDRVQcowState *s = bs->opaque;
- int l1_index, l2_index, ret;
+ unsigned int l1_index, l2_index;
uint64_t l2_offset, *l2_table;
+ int ret;
/* seek the the l2 offset in the l1 table */
l1_index = offset >> (s->l2_bits + s->cluster_bits);
if (l1_index >= s->l1_size) {
ret = qcow2_grow_l1_table(bs, l1_index + 1);
- if (ret < 0)
- return 0;
+ if (ret < 0) {
+ return ret;
+ }
}
l2_offset = s->l1_table[l1_index];
/* load the l2 table in memory */
l2_offset &= ~QCOW_OFLAG_COPIED;
l2_table = l2_load(bs, l2_offset);
- if (l2_table == NULL)
- return 0;
+ if (l2_table == NULL) {
+ return -EIO;
+ }
} else {
if (l2_offset)
qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t));
l2_table = l2_allocate(bs, l1_index);
- if (l2_table == NULL)
- return 0;
+ if (l2_table == NULL) {
+ return -EIO;
+ }
l2_offset = s->l1_table[l1_index] & ~QCOW_OFLAG_COPIED;
}
*new_l2_offset = l2_offset;
*new_l2_index = l2_index;
- return 1;
+ return 0;
}
/*
int nb_csectors;
ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
- if (ret == 0)
+ if (ret < 0) {
return 0;
+ }
cluster_offset = be64_to_cpu(l2_table[l2_index]);
if (cluster_offset & QCOW_OFLAG_COPIED)
qcow2_free_any_clusters(bs, cluster_offset, 1);
cluster_offset = qcow2_alloc_bytes(bs, compressed_size);
+ if (cluster_offset < 0) {
+ return 0;
+ }
+
nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
(cluster_offset >> 9);
return 0;
}
-int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, uint64_t cluster_offset,
- QCowL2Meta *m)
+int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
{
BDRVQcowState *s = bs->opaque;
int i, j = 0, l2_index, ret;
uint64_t *old_cluster, start_sect, l2_offset, *l2_table;
+ uint64_t cluster_offset = m->cluster_offset;
if (m->nb_clusters == 0)
return 0;
goto err;
}
- ret = -EIO;
/* update L2 table */
- if (!get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index))
+ ret = get_cluster_table(bs, m->offset, &l2_table, &l2_offset, &l2_index);
+ if (ret < 0) {
goto err;
+ }
for (i = 0; i < m->nb_clusters; i++) {
/* if two concurrent writes happen to the same unallocated cluster
/*
* alloc_cluster_offset
*
- * For a given offset of the disk image, return cluster offset in
- * qcow2 file.
- *
+ * For a given offset of the disk image, return cluster offset in qcow2 file.
* If the offset is not found, allocate a new cluster.
*
- * Return the cluster offset if successful,
- * Return 0, otherwise.
+ * If the cluster was already allocated, m->nb_clusters is set to 0,
+ * m->depends_on is set to NULL and the other fields in m are meaningless.
+ *
+ * If the cluster is newly allocated, m->nb_clusters is set to the number of
+ * contiguous clusters that have been allocated. This may be 0 if the request
+ * conflict with another write request in flight; in this case, m->depends_on
+ * is set and the remaining fields of m are meaningless.
*
+ * If m->nb_clusters is non-zero, the other fields of m are valid and contain
+ * information about the first allocated cluster.
+ *
+ * Return 0 on success and -errno in error cases
*/
-
uint64_t qcow2_alloc_cluster_offset(BlockDriverState *bs,
uint64_t offset,
int n_start, int n_end,
{
BDRVQcowState *s = bs->opaque;
int l2_index, ret;
- uint64_t l2_offset, *l2_table, cluster_offset;
- int nb_clusters, i = 0;
+ uint64_t l2_offset, *l2_table;
+ int64_t cluster_offset;
+ unsigned int nb_clusters, i = 0;
QCowL2Meta *old_alloc;
ret = get_cluster_table(bs, offset, &l2_table, &l2_offset, &l2_index);
- if (ret == 0)
- return 0;
+ if (ret < 0) {
+ return ret;
+ }
nb_clusters = size_to_clusters(s, n_end << 9);
cluster_offset &= ~QCOW_OFLAG_COPIED;
m->nb_clusters = 0;
+ m->depends_on = NULL;
goto out;
}
/* allocate a new cluster */
cluster_offset = qcow2_alloc_clusters(bs, nb_clusters * s->cluster_size);
+ if (cluster_offset < 0) {
+ return cluster_offset;
+ }
/* save info needed for meta data update */
m->offset = offset;
out:
m->nb_available = MIN(nb_clusters << (s->cluster_bits - 9), n_end);
+ m->cluster_offset = cluster_offset;
*num = m->nb_available - n_start;
- return cluster_offset;
+ return 0;
}
static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
projects / mirror_qemu.git / blobdiff