On 09/13/2017 12:03 PM, Eric Blake wrote: > We are gradually moving away from sector-based interfaces, towards > byte-based. In the common case, allocation is unlikely to ever use > values that are not naturally sector-aligned, but it is possible > that byte-based values will let us be more precise about allocation > at the end of an unaligned file that can do byte-based access. > > Changing the name of the function from bdrv_get_block_status_above() > to bdrv_block_status_above() ensures that the compiler enforces that > all callers are updated. For now, the io.c layer still assert()s > that all callers are sector-aligned, but that can be relaxed when a > later patch implements byte-based block status in the drivers. > > For the most part this patch is just the addition of scaling at the > callers followed by inverse scaling at bdrv_block_status(). But some > code, particularly bdrv_block_status(), gets a lot simpler because > it no longer has to mess with sectors. Likewise, mirror code no > longer computes s->granularity >> BDRV_SECTOR_BITS, and can therefore > drop an assertion (fix a neighboring assertion to use is_power_of_2 > while there). >
Huh, I suppose so, yeah. Do you have a test that covers what happens in this newly available use case? > For ease of review, bdrv_get_block_status() was tackled separately. > > Signed-off-by: Eric Blake <[email protected]> > Looks mechanically correct, anyway. Reviewed-by: John Snow <[email protected]>
