Re: virt_to_offset() (Re: [RFC][PATCH] Make cryptoapi non-optional?)

Matt Mackall
2003-08-10T09:06:11Z

On Sun, Aug 10, 2003 at 01:30:41AM -0700, David S. Miller wrote:
> On Sun, 10 Aug 2003 17:32:15 +0900 (JST)
> YOSHIFUJI Hideaki / _$B5HF#1QL@ <yoshfuji@linux-ipv6.org> wrote:
>
> > BTW, we spread ((long) ptr & ~PAGE_MASK); it seems ugly.
> > Why don't we have vert_to_offset(ptr) or something like this?
> > #define virt_to_offset(ptr) ((unsigned long) (ptr) & ~PAGE_MASK)
> > Is this bad idea?
>
> With some name like "virt_to_pageoff()" it sounds like a great
> idea.

Had the same thought. Nowhere good to stick it, so I put it in mm.

diff -urN -X dontdiff orig/include/linux/mm.h work/include/linux/mm.h
--- orig/include/linux/mm.h 2003-08-10 03:16:39.000000000 -0500
+++ work/include/linux/mm.h 2003-08-10 04:03:25.000000000 -0500
@@ -400,6 +400,8 @@
#define VM_FAULT_MINOR 1
#define VM_FAULT_MAJOR 2

+#define virt_to_pageoff(p) ((unsigned long)(p) & ~PAGE_MASK)
+
extern void show_free_areas(void);

struct page *shmem_nopage(struct vm_area_struct * vma,

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--
Matt Mackall : http://www.selenic.com : of or relating to the moon