Re: [Qemu-devel] [PULL v2 33/37] block: vhdx - add .bdrv_create() support

[Jeff Cody]

On Fri, Feb 21, 2014 at 01:06:43PM +0100, Alexander Graf wrote:
> 
> On 08.11.2013, at 11:12, Stefan Hajnoczi <address@hidden> wrote:
> 
> > From: Jeff Cody <address@hidden>
> > 
> > This adds support for VHDX image creation, for images of type "Fixed"
> > and "Dynamic".  "Differencing" types (i.e., VHDX images with backing
> > files) are currently not supported.
> > 
> > Options for image creation include:
> >    * log size:
> >        The size of the journaling log for VHDX.  Minimum is 1MB,
> >        and it must be a multiple of 1MB. Invalid log sizes will be
> >        silently fixed by rounding up to the nearest MB.
> > 
> >        Default is 1MB.
> > 
> >    * block size:
> >        This is the size of a payload block.  The range is 1MB to 256MB,
> >        inclusive, and must be a multiple of 1MB as well.  Invalid sizes
> >        and multiples will be silently fixed.  If '0' is passed, then
> >        a sane size is chosen (depending on virtual image size).
> > 
> >        Default is 0 (Auto-select).
> > 
> >    * subformat:
> >        - "dynamic"
> >            An image without data pre-allocated.
> >        - "fixed"
> >            An image with data pre-allocated.
> > 
> >        Default is "dynamic"
> > 
> > When creating the image file, the lettered sections are created:
> > 
> > -----------------------------------------------------------------.
> > |   (A)    |   (B)    |    (C)    |     (D)       |     (E)
> > |  File ID |  Header1 |  Header 2 |  Region Tbl 1 |  Region Tbl 2
> > |          |          |           |               |
> > .-----------------------------------------------------------------.
> > 0         64KB      128KB       192KB           256KB          320KB
> > 
> > .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------.
> > |     (F)     |     (G)       |    (H)    |
> > | Journal Log |  BAT / Bitmap |  Metadata |  .... data ......
> > |             |               |           |
> > .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------.
> > 1MB         (var.)          (var.)      (var.)
> > 
> > Signed-off-by: Jeff Cody <address@hidden>
> > Signed-off-by: Stefan Hajnoczi <address@hidden>
> > ---
> > block/vhdx.c | 558 
> > +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> > block/vhdx.h |  15 +-
> > 2 files changed, 572 insertions(+), 1 deletion(-)
> > 
> > 
> 
> [..…]
> 
> > /* Header for the region table block */
> > +#define VHDX_REGION_SIGNATURE  0x69676572  /* "regi" in ASCII */
> > typedef struct QEMU_PACKED VHDXRegionTableHeader {
> >     uint32_t    signature;              /* "regi" in ASCII */
> >     uint32_t    checksum;               /* CRC-32C hash of the 64KB table */
> > @@ -238,6 +247,7 @@ typedef uint64_t VHDXBatEntry;
> > #define VHDX_METADATA_MAX_ENTRIES 2047  /* not including the header */
> > #define VHDX_METADATA_TABLE_MAX_SIZE \
> >     (VHDX_METADATA_ENTRY_SIZE * (VHDX_METADATA_MAX_ENTRIES+1))
> > +#define VHDX_METADATA_SIGNATURE 0x617461646174656D  /* "metadata" in ASCII 
> > */
> 
> This is missing a "ULL" tag. There are a few places where compilation of vhdx 
> spawns warnings on 32bit hosts - I haven't checked all of them.
> 
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c: In function 
> 'vhdx_open':
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c:957: warning: 
> integer constant is too large for 'long' type
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c: In function 
> 'vhdx_block_translate':
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c:1027: warning: 
> integer constant is too large for 'long' type
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c: In function 
> 'vhdx_create_new_metadata':
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c:1455: warning: 
> integer constant is too large for 'long' type
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c: In function 
> 'vhdx_create':
> 02/21 12:22:14 ERROR|     utils:0144| [stderr] block/vhdx.c:1812: warning: 
> integer constant is too large for 'long' type
>

Thanks Alex.  I'll put together a 32-bit vm to build with and verify
everything, and then post patches to fix.