[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH 1/3] vmstate: introduce calc_size VMStateField
From: |
Peter Maydell |
Subject: |
Re: [Qemu-devel] [PATCH 1/3] vmstate: introduce calc_size VMStateField |
Date: |
Mon, 26 Dec 2011 15:20:25 +0000 |
On 26 December 2011 10:03, Mitsyanko Igor <address@hidden> wrote:
> New calc_size field in VMStateField is supposed to help us easily add
> save/restore
> support of dynamically allocated buffers in device's states.
> There are some cases when information on size of dynamically allocated buffer
> is
> already presented in specific device's state structure, but in such a form,
> that
> can not be used with existing VMStateField interface. Currently, we either
> can get size from
> another variable in device's state as it is with VMSTATE_VBUFFER_* macros, or
> we can
> also multiply value kept in a variable by a constant with
> VMSTATE_BUFFER_MULTIPLY
> macro. If we need to perform any other action, we're forced to add additional
> variable with size information to device state structure with the only
> intention
> to use it in VMStateDescription structure. This approach is not very pretty.
> Adding extra
> flags to VMStateFlags enum for every other possible operation with size field
> seems redundant, and still it would't cover cases when we need to perform a
> set of
> operations to get size value.
> With this new .calc_size field we can calculate size of dynamic array in
> whichever
> way we need.
>
> Signed-off-by: Mitsyanko Igor <address@hidden>
It seems a bit curious that this patch removes the existing (although admittedly
unused) VMSTATE_BUFFER_MULTIPLY but doesn't actually say so in the
commit message.
> ---
> hw/hw.h | 14 +++++++-------
> savevm.c | 14 ++++++++------
> 2 files changed, 15 insertions(+), 13 deletions(-)
>
> diff --git a/hw/hw.h b/hw/hw.h
> index efa04d1..8ce4475 100644
> --- a/hw/hw.h
> +++ b/hw/hw.h
> @@ -303,9 +303,9 @@ enum VMStateFlags {
> VMS_ARRAY_OF_POINTER = 0x040,
> VMS_VARRAY_UINT16 = 0x080, /* Array with size in uint16_t field */
> VMS_VBUFFER = 0x100, /* Buffer with size in int32_t field */
> - VMS_MULTIPLY = 0x200, /* multiply "size" field by field_size */
> - VMS_VARRAY_UINT8 = 0x400, /* Array with size in uint8_t field*/
> - VMS_VARRAY_UINT32 = 0x800, /* Array with size in uint32_t field*/
> + VMS_CALC_SIZE = 0x200, /* calculate size of dynamic buffer */
> + VMS_VARRAY_UINT8 = 0x400, /* Array with size in uint8_t field */
> + VMS_VARRAY_UINT32 = 0x800, /* Array with size in uint32_t field */
These unrelated whitespace fixes are confusing -- please drop them.
-- PMM
[Qemu-devel] [PATCH 2/3] hw/sd.c: add SD card save/load support, Mitsyanko Igor, 2011/12/26