Re: [PATCH v4 16/16] block/io: use int64_t bytes in copy_range

[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 now copy_range parameters which are already 64bit to signed
> type.
> 
> It's safe as we don't work with requests overflowing BDRV_MAX_LENGTH
> (which is less than INT64_MAX), and do check the requests in
> bdrv_co_copy_range_internal() (by bdrv_check_request32(), which calls
> bdrv_check_request()).
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
> ---
>  include/block/block.h     |  6 +++---
>  include/block/block_int.h | 12 ++++++------
>  block/io.c                | 22 +++++++++++-----------
>  block/trace-events        |  4 ++--
>  4 files changed, 22 insertions(+), 22 deletions(-)
> 

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

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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