diff options
| -rw-r--r-- | block/qcow2-cluster.c | 29 | ||||
| -rw-r--r-- | block/qcow2.h | 5 |
2 files changed, 21 insertions, 13 deletions
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c index 8f4ef0d48a..8ed1f7dd2a 100644 --- a/block/qcow2-cluster.c +++ b/block/qcow2-cluster.c @@ -875,13 +875,9 @@ static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset, * newly allocated cluster. * * -errno: in error cases - * - * TODO Get rid of n_start, n_end - * TODO Make *bytes actually behave as specified above */ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, - uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m, - int n_start, int n_end) + uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m) { BDRVQcowState *s = bs->opaque; int l2_index; @@ -901,8 +897,11 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, * Calculate the number of clusters to look for. We stop at L2 table * boundaries to keep things simple. */ + nb_clusters = + size_to_clusters(s, offset_into_cluster(s, guest_offset) + *bytes); + l2_index = offset_to_l2_index(s, guest_offset); - nb_clusters = MIN(size_to_clusters(s, *bytes), s->l2_size - l2_index); + nb_clusters = MIN(nb_clusters, s->l2_size - l2_index); /* Find L2 entry for the first involved cluster */ ret = get_cluster_table(bs, guest_offset, &l2_table, &l2_index); @@ -954,10 +953,13 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, * newly allocated cluster to the end of the aread that the write * request actually writes to (excluding COW at the end) */ - int requested_sectors = n_end; + int requested_sectors = + (*bytes + offset_into_cluster(s, guest_offset)) + >> BDRV_SECTOR_BITS; int avail_sectors = nb_clusters << (s->cluster_bits - BDRV_SECTOR_BITS); - int alloc_n_start = *host_offset == 0 ? n_start : 0; + int alloc_n_start = offset_into_cluster(s, guest_offset) + >> BDRV_SECTOR_BITS; int nb_sectors = MIN(requested_sectors, avail_sectors); if (*host_offset == 0) { @@ -984,7 +986,9 @@ static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset, qemu_co_queue_init(&(*m)->dependent_requests); QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight); - *bytes = nb_clusters * s->cluster_size; + *bytes = MIN(*bytes, (nb_sectors * BDRV_SECTOR_SIZE) + - offset_into_cluster(s, guest_offset)); + assert(*bytes != 0); } else { *bytes = 0; return 0; @@ -1139,10 +1143,9 @@ again: alloc_n_end = n_end; } - cur_bytes = nb_clusters * s->cluster_size; + cur_bytes = MIN(cur_bytes, ((alloc_n_end - alloc_n_start) << BDRV_SECTOR_BITS)); - ret = handle_alloc(bs, offset, &cluster_offset, &cur_bytes, m, - alloc_n_start, alloc_n_end); + ret = handle_alloc(bs, offset, &cluster_offset, &cur_bytes, m); if (ret < 0) { return ret; } @@ -1150,7 +1153,7 @@ again: if (!*host_offset) { *host_offset = cluster_offset; } - nb_clusters = size_to_clusters(s, cur_bytes); + nb_clusters = size_to_clusters(s, cur_bytes + offset_into_cluster(s, offset)); /* Some cleanup work */ done: diff --git a/block/qcow2.h b/block/qcow2.h index c4eaf670ec..32806bd035 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -271,6 +271,11 @@ static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset) return offset & ~(s->cluster_size - 1); } +static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset) +{ + return offset & (s->cluster_size - 1); +} + static inline int size_to_clusters(BDRVQcowState *s, int64_t size) { return (size + (s->cluster_size - 1)) >> s->cluster_bits; |