Re: [Qemu-devel] [PATCH 4/6] libqblock internal used functions

[Wenchao Xia]

于 2012-9-3 23:18, Paolo Bonzini 写道:
> Il 03/09/2012 16:28, Eric Blake ha scritto:
> > > > +/* this file contains helper function used internally. */
> > > > +#define SECTOR_SIZE (512)
> > Hard-coding this feels wrong, in this day and age of disks with 4096
> > sectors.  Why isn't this a per-image property?
>
> In this day and age of disks with 4096 sectors, Linux does not provide a
> way to query the required alignment for O_DIRECT...
>
> Paolo
in block.h:
#define BDRV_SECTOR_BITS   9
#define BDRV_SECTOR_SIZE   (1ULL << BDRV_SECTOR_BITS)
#define BDRV_SECTOR_MASK   ~(BDRV_SECTOR_SIZE - 1)
  it seems block size is always 512 in qemu block layer, so I can
ignore the 4096 case, do you think so?
--
Best Regards

Wenchao Xia