Re: [V3 PATCH 1/2] tmpfs: add fallocate support

[KAMEZAWA Hiroyuki]

On Wed, 23 Nov 2011 21:46:39 -0500
KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote:

> >> + Â Â while (index < end) {
> >> + Â Â Â Â Â Â ret = shmem_getpage(inode, index, &page, SGP_WRITE, NULL);
> >
> > If the 'page' for index exists before this call, this will return the page without
> > allocaton.
> >
> > Then, the page may not be zero-cleared. I think the page should be zero-cleared.
> 
> No. fallocate shouldn't destroy existing data. It only ensure
> subsequent file access don't make ENOSPC error.
> 
      FALLOC_FL_KEEP_SIZE
              This flag allocates and initializes to zero the disk  space
              within the range specified by offset and len. ....

just manual is unclear ? it seems that the range [offset, offset+len) is
zero cleared after the call.

Thanks,
-kame

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/