Re: [RFC PATCH v2 06/25] include/block/block_int: split header into I/O and global state API

[Emanuele Giuseppe Esposito]

On 07/10/2021 12:52, Stefan Hajnoczi wrote:
> On Tue, Oct 05, 2021 at 10:31:56AM -0400, Emanuele Giuseppe Esposito wrote:
> > +int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, int64_t src_offset,
> > +                                         BdrvChild *dst, int64_t dst_offset,
> > +                                         int64_t bytes,
> > +                                         BdrvRequestFlags read_flags,
> > +                                         BdrvRequestFlags write_flags);
> > +int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, int64_t src_offset,
> > +                                       BdrvChild *dst, int64_t dst_offset,
> > +                                       int64_t bytes,
> > +                                       BdrvRequestFlags read_flags,
> > +                                       BdrvRequestFlags write_flags);
>
> These look like I/O APIs to me. Are they in the GS API because only
> qemu-img.c call copy_range? I thought SCSI emulation might call it too,
> but grep says otherwise.

SCSI (iscsi.c) implements the function pointer 
(*bdrv_co_copy_range_from/to), but does not call the function itself. 
However, later in the patches I put the function pointer as I/O.

These two functions are only tested by test-replication and thus are 
always under BQL when tested. But after looking at them again, and since 
they internally use only I/O APIs, I think we can move them to the I/O API.

Thank you,
Emanuele