Re: [RFC PATCH v2 04/25] include/block/block: split header into I/O and global state API

[Paolo Bonzini]

On 07/10/21 12:54, Emanuele Giuseppe Esposito wrote:
> > > +int bdrv_block_status(BlockDriverState *bs, int64_t offset,
> > > +                      int64_t bytes, int64_t *pnum, int64_t *map,
> > > +                      BlockDriverState **file);
> >
> > This function just called bdrv_block_status_above(), which is in the I/O
> > API. I think it's safe to move this to the I/O API or else
> > bdrv_block_status_above() shouldn't be there :).
>
> It *seems* that while bdrv_block_status_above() is an I/O, probably 
> running in some coroutine (from here its internal qemu_in_coroutine 
> check), bdrv_block_status might be called from the main loop (or 
> alternatively the function is never invoked in the tests, so the 
> assertion never triggered).
>
> Maybe bdrv_block_status_above is one of the few functions that are both 
> I/O and Main loop? I put it in I/O as it can't have the assertion.

No, they are both I/O.  Callers of bdrv_block_status are hw/nvme and 
qemu-img.c; while the latter can be either (it does not have iothreads), 
hw/nvme is definitely I/O.

Paolo