tools/qemu/patches/0006-VMDK-add-field-BDRVVmdkState.desc_offset.patch

   1 From 1c1781fa1c45a7c012f7b2c4be1be372f19e3cc6 Mon Sep 17 00:00:00 2001
   2 From: Fam Zheng <famcool@gmail.com>
   3 Date: Tue, 12 Jul 2011 19:56:32 +0800
   4 Subject: [PATCH 06/12] VMDK: add field BDRVVmdkState.desc_offset
   5
   6 There are several occurrence of magic number 0x200 as the descriptor
   7 offset within mono sparse image file. This is not the case for images
   8 with separate descriptor file. So a field is added to BDRVVmdkState to
   9 hold the correct value.
  10
  11 Signed-off-by: Fam Zheng <famcool@gmail.com>
  12 Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  13 Signed-off-by: Kevin Wolf <kwolf@redhat.com>
  14 ---
  15  block/vmdk.c | 27 ++++++++++++++++++---------
  16  1 file changed, 18 insertions(+), 9 deletions(-)
  17
  18 --- a/block/vmdk.c
  19 +++ b/block/vmdk.c
  20 @@ -81,6 +81,7 @@ typedef struct VmdkExtent {
  21  } VmdkExtent;
  22
  23  typedef struct BDRVVmdkState {
  24 +    int desc_offset;
  25      uint32_t parent_cid;
  26      int num_extents;
  27      /* Extent array with num_extents entries, ascend ordered by address */
  28 @@ -175,10 +176,11 @@ static uint32_t vmdk_read_cid(BlockDrive
  29      uint32_t cid;
  30      const char *p_name, *cid_str;
  31      size_t cid_str_size;
  32 +    BDRVVmdkState *s = bs->opaque;
  33
  34 -    /* the descriptor offset = 0x200 */
  35 -    if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE)
  36 +    if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) {
  37          return 0;
  38 +    }
  39
  40      if (parent) {
  41          cid_str = "parentCID";
  42 @@ -200,10 +202,12 @@ static int vmdk_write_cid(BlockDriverSta
  43  {
  44      char desc[DESC_SIZE], tmp_desc[DESC_SIZE];
  45      char *p_name, *tmp_str;
  46 +    BDRVVmdkState *s = bs->opaque;
  47
  48 -    /* the descriptor offset = 0x200 */
  49 -    if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE)
  50 -        return -1;
  51 +    memset(desc, 0, sizeof(desc));
  52 +    if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) {
  53 +        return -EIO;
  54 +    }
  55
  56      tmp_str = strstr(desc,"parentCID");
  57      pstrcpy(tmp_desc, sizeof(tmp_desc), tmp_str);
  58 @@ -213,8 +217,9 @@ static int vmdk_write_cid(BlockDriverSta
  59          pstrcat(desc, sizeof(desc), tmp_desc);
  60      }
  61
  62 -    if (bdrv_pwrite_sync(bs->file, 0x200, desc, DESC_SIZE) < 0)
  63 -        return -1;
  64 +    if (bdrv_pwrite_sync(bs->file, s->desc_offset, desc, DESC_SIZE) < 0) {
  65 +        return -EIO;
  66 +    }
  67      return 0;
  68  }
  69
  70 @@ -402,10 +407,11 @@ static int vmdk_parent_open(BlockDriverS
  71  {
  72      char *p_name;
  73      char desc[DESC_SIZE];
  74 +    BDRVVmdkState *s = bs->opaque;
  75
  76 -    /* the descriptor offset = 0x200 */
  77 -    if (bdrv_pread(bs->file, 0x200, desc, DESC_SIZE) != DESC_SIZE)
  78 +    if (bdrv_pread(bs->file, s->desc_offset, desc, DESC_SIZE) != DESC_SIZE) {
  79          return -1;
  80 +    }
  81
  82      if ((p_name = strstr(desc,"parentFileNameHint")) != NULL) {
  83          char *end_name;
  84 @@ -506,8 +512,10 @@ static int vmdk_open_vmdk3(BlockDriverSt
  85      int ret;
  86      uint32_t magic;
  87      VMDK3Header header;
  88 +    BDRVVmdkState *s = bs->opaque;
  89      VmdkExtent *extent;
  90
  91 +    s->desc_offset = 0x200;
  92      ret = bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header));
  93      if (ret < 0) {
  94          goto fail;
  95 @@ -539,6 +547,7 @@ static int vmdk_open_vmdk4(BlockDriverSt
  96      BDRVVmdkState *s = bs->opaque;
  97      VmdkExtent *extent;
  98
  99 +    s->desc_offset = 0x200;
 100      ret = bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header));
 101      if (ret < 0) {
 102          goto fail;