vmdk3ro.patch

   1 From: Fam Zheng
   2 Subject: [Qemu-devel] [PATCH v2 1/2] vmdk: Allow read only open of VMDK version 3
   3 Date: Thu, 28 Nov 2013 09:48:03 +0800
   4 URL: https://lists.gnu.org/archive/html/qemu-devel/2013-11/msg03652.html
   5
   6 Signed-off-by: Fam Zheng <address@hidden>
   7 ---
   8  block/vmdk.c | 9 ++++++++-
   9  1 file changed, 8 insertions(+), 1 deletion(-)
  10
  11 diff --git a/block/vmdk.c b/block/vmdk.c
  12 index a7ebd0f..6fd20dc 100644
  13 --- a/block/vmdk.c
  14 +++ b/block/vmdk.c
  15 @@ -605,13 +605,20 @@ static int vmdk_open_vmdk4(BlockDriverState *bs,
  16          header = footer.header;
  17      }
  18
  19 -    if (le32_to_cpu(header.version) >= 3) {
  20 +    if (le32_to_cpu(header.version) > 3) {
  21          char buf[64];
  22          snprintf(buf, sizeof(buf), "VMDK version %d",
  23                   le32_to_cpu(header.version));
  24          qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
  25                  bs->device_name, "vmdk", buf);
  26          return -ENOTSUP;
  27 +    } else if (le32_to_cpu(header.version) == 3 && (flags & BDRV_O_RDWR)) {
  28 +        /* VMware KB 2064959 explains that version 3 added support for
  29 +         * persistent changed block tracking (CBT), and backup software can
  30 +         * read it as version=1 if it doesn't care about the changed area
  31 +         * information. So we are safe to enable read only. */
  32 +        error_setg(errp, "VMDK version 3 must be read only");
  33 +        return -EINVAL;
  34      }
  35
  36      if (le32_to_cpu(header.num_gtes_per_gt) > 512) { --
  37 1.8.4.2