On Tue, Dec 06, 2011 at 01:59:48PM +0100, Kevin Wolf wrote:
> >> +
> >> + ret = bdrv_pread(bs->file, sizeof(header), state->bitmap,
> >> + state->bitmap_size);
> >> + if (ret != state->bitmap_size) {
> >> + goto fail;
> >> + }
> >
> > Reading the entire bitmap in memory is not acceptable, it may be huge.
> > Better mmap it and use msync(MS_SYNC) when writing it back. This way the
> > host can free memory easily upon pressure.
>
> You can't use mmap in block drivers. It would only work with raw-posix
> backends, if at all.
>
> Kevin
This is just the bitmap, a plain file. Why would you want to use
anything other than a plain file to use as storage for the bitmap?
