diff options
| -rw-r--r-- | block/qcow2-refcount.c | 20 | ||||
| -rw-r--r-- | block/qcow2.h | 6 |
2 files changed, 19 insertions, 7 deletions
diff --git a/block/qcow2-refcount.c b/block/qcow2-refcount.c index 46082aeac1..1c63ac244a 100644 --- a/block/qcow2-refcount.c +++ b/block/qcow2-refcount.c @@ -31,7 +31,8 @@ #include "qemu/bswap.h" #include "qemu/cutils.h" -static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size); +static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size, + uint64_t max); static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs, int64_t offset, int64_t length, uint64_t addend, bool decrease, enum qcow2_discard_type type); @@ -362,7 +363,7 @@ static int alloc_refcount_block(BlockDriverState *bs, } /* Allocate the refcount block itself and mark it as used */ - int64_t new_block = alloc_clusters_noref(bs, s->cluster_size); + int64_t new_block = alloc_clusters_noref(bs, s->cluster_size, INT64_MAX); if (new_block < 0) { return new_block; } @@ -954,7 +955,8 @@ int qcow2_update_cluster_refcount(BlockDriverState *bs, /* return < 0 if error */ -static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size) +static int64_t alloc_clusters_noref(BlockDriverState *bs, uint64_t size, + uint64_t max) { BDRVQcow2State *s = bs->opaque; uint64_t i, nb_clusters, refcount; @@ -979,9 +981,9 @@ retry: } /* Make sure that all offsets in the "allocated" range are representable - * in an int64_t */ + * in the requested max */ if (s->free_cluster_index > 0 && - s->free_cluster_index - 1 > (INT64_MAX >> s->cluster_bits)) + s->free_cluster_index - 1 > (max >> s->cluster_bits)) { return -EFBIG; } @@ -1001,7 +1003,7 @@ int64_t qcow2_alloc_clusters(BlockDriverState *bs, uint64_t size) BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC); do { - offset = alloc_clusters_noref(bs, size); + offset = alloc_clusters_noref(bs, size, QCOW_MAX_CLUSTER_OFFSET); if (offset < 0) { return offset; } @@ -1083,7 +1085,11 @@ int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size) free_in_cluster = s->cluster_size - offset_into_cluster(s, offset); do { if (!offset || free_in_cluster < size) { - int64_t new_cluster = alloc_clusters_noref(bs, s->cluster_size); + int64_t new_cluster; + + new_cluster = alloc_clusters_noref(bs, s->cluster_size, + MIN(s->cluster_offset_mask, + QCOW_MAX_CLUSTER_OFFSET)); if (new_cluster < 0) { return new_cluster; } diff --git a/block/qcow2.h b/block/qcow2.h index 29c98d87a0..8662b68575 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -42,6 +42,12 @@ #define QCOW_MAX_CRYPT_CLUSTERS 32 #define QCOW_MAX_SNAPSHOTS 65536 +/* Field widths in qcow2 mean normal cluster offsets cannot reach + * 64PB; depending on cluster size, compressed clusters can have a + * smaller limit (64PB for up to 16k clusters, then ramps down to + * 512TB for 2M clusters). */ +#define QCOW_MAX_CLUSTER_OFFSET ((1ULL << 56) - 1) + /* 8 MB refcount table is enough for 2 PB images at 64k cluster size * (128 GB for 512 byte clusters, 2 EB for 2 MB clusters) */ #define QCOW_MAX_REFTABLE_SIZE S_8MiB |