diff --git a/block/vmdk.c b/block/vmdk.c index 7e07c0f6e6..cc19e207d1 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -48,6 +48,8 @@ #define VMDK_UNALLOC (-2) #define VMDK_ZEROED (-3) +#define BLOCK_OPT_ZEROED_GRAIN "zeroed_grain" + typedef struct { uint32_t version; uint32_t flags; @@ -1262,7 +1264,7 @@ static coroutine_fn int vmdk_co_write(BlockDriverState *bs, int64_t sector_num, static int vmdk_create_extent(const char *filename, int64_t filesize, - bool flat, bool compress) + bool flat, bool compress, bool zeroed_grain) { int ret, i; int fd = 0; @@ -1284,9 +1286,10 @@ static int vmdk_create_extent(const char *filename, int64_t filesize, } magic = cpu_to_be32(VMDK4_MAGIC); memset(&header, 0, sizeof(header)); - header.version = 1; - header.flags = - 3 | (compress ? VMDK4_FLAG_COMPRESS | VMDK4_FLAG_MARKER : 0); + header.version = zeroed_grain ? 2 : 1; + header.flags = 3 + | (compress ? VMDK4_FLAG_COMPRESS | VMDK4_FLAG_MARKER : 0) + | (zeroed_grain ? VMDK4_FLAG_ZERO_GRAIN : 0); header.compressAlgorithm = compress ? VMDK4_COMPRESSION_DEFLATE : 0; header.capacity = filesize / 512; header.granularity = 128; @@ -1467,6 +1470,7 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options) char parent_desc_line[BUF_SIZE] = ""; uint32_t parent_cid = 0xffffffff; uint32_t number_heads = 16; + bool zeroed_grain = false; const char desc_template[] = "# Disk DescriptorFile\n" "version=1\n" @@ -1502,6 +1506,8 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options) flags |= options->value.n ? BLOCK_FLAG_COMPAT6 : 0; } else if (!strcmp(options->name, BLOCK_OPT_SUBFMT)) { fmt = options->value.s; + } else if (!strcmp(options->name, BLOCK_OPT_ZEROED_GRAIN)) { + zeroed_grain |= options->value.n; } options++; } @@ -1588,7 +1594,8 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options) snprintf(ext_filename, sizeof(ext_filename), "%s%s", path, desc_filename); - if (vmdk_create_extent(ext_filename, size, flat, compress)) { + if (vmdk_create_extent(ext_filename, size, + flat, compress, zeroed_grain)) { return -EINVAL; } filesize -= size; @@ -1714,6 +1721,11 @@ static QEMUOptionParameter vmdk_create_options[] = { "VMDK flat extent format, can be one of " "{monolithicSparse (default) | monolithicFlat | twoGbMaxExtentSparse | twoGbMaxExtentFlat | streamOptimized} " }, + { + .name = BLOCK_OPT_ZEROED_GRAIN, + .type = OPT_FLAG, + .help = "Enable efficient zero writes using the zeroed-grain GTE feature" + }, { NULL } };