From e1da9b2433f78c4de3bac8c2a97173c648d212c0 Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Tue, 12 Jul 2011 19:56:32 +0800 Subject: [PATCH] VMDK: add field BDRVVmdkState.desc_offset There are several occurrence of magic number 0x200 as the descriptor offset within mono sparse image file. This is not the case for images with separate descriptor file. So a field is added to BDRVVmdkState to hold the correct value. Signed-off-by: Fam Zheng Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block/vmdk.c | 27 ++++++++++++++++++--------- 1 file changed, 18 insertions(+), 9 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index 6d7b497202..529ae90fdb 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -81,6 +81,7 @@ typedef struct VmdkExtent { } VmdkExtent; typedef struct BDRVVmdkState { + int desc_offset; uint32_t parent_cid; int num_extents; /* Extent array with num_extents entries, ascend ordered by address */ @@ -175,10 +176,11 @@ static uint32_t vmdk_read_cid(BlockDriverState *bs, int parent) uint32_t cid; const char *p_name, *cid_str; size_t cid_str_size; + BDRVVmdkState *s = bs->opaque; - /* the descriptor offset = 0x200 */ - if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE) + if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) { return 0; + } if (parent) { cid_str = "parentCID"; @@ -200,10 +202,12 @@ static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid) { char desc[DESC_SIZE], tmp_desc[DESC_SIZE]; char *p_name, *tmp_str; + BDRVVmdkState *s = bs->opaque; - /* the descriptor offset = 0x200 */ - if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE) - return -1; + memset(desc, 0, sizeof(desc)); + if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) { + return -EIO; + } tmp_str = strstr(desc,"parentCID"); pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str); @@ -213,8 +217,9 @@ static int vmdk_write_cid(BlockDriverState *bs, uint32_t cid) pstrcat(desc, sizeof(desc), tmp_desc); } - if (bdrv_pwrite_sync(bs->file, 0x200, desc, DESC_SIZE) < 0) - return -1; + if (bdrv_pwrite_sync(bs->file, s->desc_offset, desc, DESC_SIZE) < 0) { + return -EIO; + } return 0; } @@ -402,10 +407,11 @@ static int vmdk_parent_open(BlockDriverState *bs) { char *p_name; char desc[DESC_SIZE]; + BDRVVmdkState *s = bs->opaque; - /* the descriptor offset = 0x200 */ - if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE) + if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) { return -1; + } if ((p_name = strstr(desc,"parentFileNameHint")) != NULL) { char *end_name; @@ -506,8 +512,10 @@ static int vmdk_open_vmdk3(BlockDriverState *bs, int flags) int ret; uint32_t magic; VMDK3Header header; + BDRVVmdkState *s = bs->opaque; VmdkExtent *extent; + s->desc_offset = 0x200; ret = bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header)); if (ret < 0) { goto fail; @@ -539,6 +547,7 @@ static int vmdk_open_vmdk4(BlockDriverState *bs, int flags) BDRVVmdkState *s = bs->opaque; VmdkExtent *extent; + s->desc_offset = 0x200; ret = bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header)); if (ret < 0) { goto fail; -- 2.11.4.GIT