Re: [PATCH] mm: move sys_mmap_pgoff from util.c

From: Hugh Dickins
Date: Mon Jan 04 2010 - 12:21:35 EST


On Mon, 4 Jan 2010, Eric B Munson wrote:
> On Wed, 30 Dec 2009, Hugh Dickins wrote:
>
> > Move sys_mmap_pgoff() from mm/util.c to mm/mmap.c and mm/nommu.c,
> > where we'd expect to find such code: especially now that it contains
> > the MAP_HUGETLB handling. Revert mm/util.c to how it was in 2.6.32.
> >
> > This patch just ignores MAP_HUGETLB in the nommu case, as in 2.6.32,
> > whereas 2.6.33-rc2 reported -ENOSYS. Perhaps validate_mmap_request()
> > should reject it with -EINVAL? Add that later if necessary.
> >
> > Signed-off-by: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>
>
> I think that -ENOSYS is the correcet response in the nommu case, but
> I that can be added in a later patch.
>
> Acked-by: Eric B Munson <ebmunson@xxxxxxxxxx>

Thanks. I had believed -ENOSYS was solely for unsupported system calls,
so thought it inappropriate here; but we seem to have quite a few places
which are using it indeed for "Function not implemented", and -EINVAL is
always so very overloaded that an alternative can be a lot more helpful.
Okay, I'll send a patch to give -ENOSYS for MAP_HUGETLB on nommu, which
will be consistent with mmu.

Hugh
--
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/