diff options
Diffstat (limited to 'block/vmdk.c')
| -rw-r--r-- | block/vmdk.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/block/vmdk.c b/block/vmdk.c index 16aa29c81d..7e07c0f6e6 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -33,10 +33,13 @@ #define VMDK4_MAGIC (('K' << 24) | ('D' << 16) | ('M' << 8) | 'V') #define VMDK4_COMPRESSION_DEFLATE 1 #define VMDK4_FLAG_RGD (1 << 1) +/* Zeroed-grain enable bit */ +#define VMDK4_FLAG_ZERO_GRAIN (1 << 2) #define VMDK4_FLAG_COMPRESS (1 << 16) #define VMDK4_FLAG_MARKER (1 << 17) #define VMDK4_GD_AT_END 0xffffffffffffffffULL +#define VMDK_GTE_ZEROED 0x1 /* VMDK internal error codes */ #define VMDK_OK 0 @@ -81,6 +84,8 @@ typedef struct VmdkExtent { bool flat; bool compressed; bool has_marker; + bool has_zero_grain; + int version; int64_t sectors; int64_t end_sector; int64_t flat_start_offset; @@ -569,6 +574,8 @@ static int vmdk_open_vmdk4(BlockDriverState *bs, extent->compressed = le16_to_cpu(header.compressAlgorithm) == VMDK4_COMPRESSION_DEFLATE; extent->has_marker = le32_to_cpu(header.flags) & VMDK4_FLAG_MARKER; + extent->version = le32_to_cpu(header.version); + extent->has_zero_grain = le32_to_cpu(header.flags) & VMDK4_FLAG_ZERO_GRAIN; ret = vmdk_init_tables(bs, extent); if (ret) { /* free extent allocated by vmdk_add_extent */ @@ -839,6 +846,7 @@ static int get_cluster_offset(BlockDriverState *bs, unsigned int l1_index, l2_offset, l2_index; int min_index, i, j; uint32_t min_count, *l2_table, tmp = 0; + bool zeroed = false; if (m_data) { m_data->valid = 0; @@ -894,9 +902,13 @@ static int get_cluster_offset(BlockDriverState *bs, l2_index = ((offset >> 9) / extent->cluster_sectors) % extent->l2_size; *cluster_offset = le32_to_cpu(l2_table[l2_index]); - if (!*cluster_offset) { + if (extent->has_zero_grain && *cluster_offset == VMDK_GTE_ZEROED) { + zeroed = true; + } + + if (!*cluster_offset || zeroed) { if (!allocate) { - return VMDK_UNALLOC; + return zeroed ? VMDK_ZEROED : VMDK_UNALLOC; } /* Avoid the L2 tables update for the images that have snapshots. */ @@ -967,8 +979,8 @@ static int coroutine_fn vmdk_co_is_allocated(BlockDriverState *bs, ret = get_cluster_offset(bs, extent, NULL, sector_num * 512, 0, &offset); qemu_co_mutex_unlock(&s->lock); - /* get_cluster_offset returning 0 means success */ - ret = !ret; + + ret = (ret == VMDK_OK || ret == VMDK_ZEROED); index_in_cluster = sector_num % extent->cluster_sectors; n = extent->cluster_sectors - index_in_cluster; @@ -1111,9 +1123,9 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, if (n > nb_sectors) { n = nb_sectors; } - if (ret) { + if (ret != VMDK_OK) { /* if not allocated, try to read from parent image, if exist */ - if (bs->backing_hd) { + if (bs->backing_hd && ret != VMDK_ZEROED) { if (!vmdk_is_cid_valid(bs)) { return -EINVAL; } |