[PATCH] PG_uncached is ia64 only

As Nick points out, only ia64 uses PG_uncached.  So we can push it up into the
higher bits of the lower half of page->flags and make room for another flag on
32-bit machines.

Cc: "Luck, Tony" <[email protected]>
Cc: Jesse Barnes <[email protected]>
Cc: Jes Sorensen <[email protected]>
Cc: Nick Piggin <[email protected]>
Cc: Andy Whitcroft <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Andrew Morton 2006-06-23 02:03:06 -07:00 • committed by Linus Torvalds
commit f886ed443f

View file

@ -7,6 +7,8 @@
#include <linux/percpu.h>
#include <linux/cache.h>
#include <linux/types.h>
#include <asm/pgtable.h>
/*
@ -88,7 +90,17 @@
#define PG_nosave_free 18 /* Free, should not be written */
#define PG_buddy 19 /* Page is free, on buddy lists */
#define PG_uncached 20 /* Page has been mapped as uncached */
#if (BITS_PER_LONG > 32)
/*
* 64-bit-only flags build down from bit 31
*
* 32 bit -------------------------------| FIELDS | FLAGS |
* 64 bit | FIELDS | ?????? FLAGS |
* 63 32 0
*/
#define PG_uncached 31 /* Page has been mapped as uncached */
#endif
/*
* Global page accounting. One instance per CPU. Only unsigned longs are