Re: [PATCH v4 09/16] block/io: use int64_t bytes in driver wrappers

[Eric Blake]

On 12/11/20 12:39 PM, Vladimir Sementsov-Ogievskiy wrote:
> We are generally moving to int64_t for both offset and bytes parameters
> on all io paths.
> 
> Main motivation is realization of 64-bit write_zeroes operation for
> fast zeroing large disk chunks, up to the whole disk.
> 
> We chose signed type, to be consistent with off_t (which is signed) and
> with possibility for signed return type (where negative value means
> error).
> 
> So, convert driver wrappers parameters which are already 64bit to
> signed type.
> 
> Requests in block/io.c must never exceed BDRV_MAX_LENGTH (which is less
> than INT64_MAX), which makes the conversion to signed 64bit type safe.
> 
> Add corresponding assertions.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  block/io.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
> 

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
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