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linux-next/arch/frv/mm/cache-page.c
Peter Zijlstra 3e4d3af501 mm: stack based kmap_atomic()
Keep the current interface but ignore the KM_type and use a stack based
approach.

The advantage is that we get rid of crappy code like:

	#define __KM_PTE			\
		(in_nmi() ? KM_NMI_PTE : 	\
		 in_irq() ? KM_IRQ_PTE :	\
		 KM_PTE0)

and in general can stop worrying about what context we're in and what kmap
slots might be appropriate for that.

The downside is that FRV kmap_atomic() gets more expensive.

For now we use a CPP trick suggested by Andrew:

  #define kmap_atomic(page, args...) __kmap_atomic(page)

to avoid having to touch all kmap_atomic() users in a single patch.

[ not compiled on:
  - mn10300: the arch doesn't actually build with highmem to begin with ]

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix up drivers/gpu/drm/i915/intel_overlay.c]
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Chris Metcalf <cmetcalf@tilera.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Miller <davem@davemloft.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-26 16:52:08 -07:00

72 lines
1.9 KiB
C

/* cache-page.c: whole-page cache wrangling functions for MMU linux
*
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <asm/pgalloc.h>
/*****************************************************************************/
/*
* DCF takes a virtual address and the page may not currently have one
* - temporarily hijack a kmap_atomic() slot and attach the page to it
*/
void flush_dcache_page(struct page *page)
{
unsigned long dampr2;
void *vaddr;
dampr2 = __get_DAMPR(2);
vaddr = kmap_atomic_primary(page, __KM_CACHE);
frv_dcache_writeback((unsigned long) vaddr, (unsigned long) vaddr + PAGE_SIZE);
kunmap_atomic_primary(vaddr, __KM_CACHE);
if (dampr2) {
__set_DAMPR(2, dampr2);
__set_IAMPR(2, dampr2);
}
} /* end flush_dcache_page() */
EXPORT_SYMBOL(flush_dcache_page);
/*****************************************************************************/
/*
* ICI takes a virtual address and the page may not currently have one
* - so we temporarily attach the page to a bit of virtual space so that is can be flushed
*/
void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
unsigned long start, unsigned long len)
{
unsigned long dampr2;
void *vaddr;
dampr2 = __get_DAMPR(2);
vaddr = kmap_atomic_primary(page, __KM_CACHE);
start = (start & ~PAGE_MASK) | (unsigned long) vaddr;
frv_cache_wback_inv(start, start + len);
kunmap_atomic_primary(vaddr, __KM_CACHE);
if (dampr2) {
__set_DAMPR(2, dampr2);
__set_IAMPR(2, dampr2);
}
} /* end flush_icache_user_range() */
EXPORT_SYMBOL(flush_icache_user_range);