forked from luck/tmp_suning_uos_patched
3e4d3af501
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>
127 lines
2.9 KiB
C
127 lines
2.9 KiB
C
/* MN10300 Virtual kernel memory mappings for high memory
|
|
*
|
|
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
* - Derived from include/asm-i386/highmem.h
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public Licence
|
|
* as published by the Free Software Foundation; either version
|
|
* 2 of the Licence, or (at your option) any later version.
|
|
*/
|
|
#ifndef _ASM_HIGHMEM_H
|
|
#define _ASM_HIGHMEM_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/highmem.h>
|
|
#include <asm/kmap_types.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
/* undef for production */
|
|
#undef HIGHMEM_DEBUG
|
|
|
|
/* declarations for highmem.c */
|
|
extern unsigned long highstart_pfn, highend_pfn;
|
|
|
|
extern pte_t *kmap_pte;
|
|
extern pgprot_t kmap_prot;
|
|
extern pte_t *pkmap_page_table;
|
|
|
|
extern void __init kmap_init(void);
|
|
|
|
/*
|
|
* Right now we initialize only a single pte table. It can be extended
|
|
* easily, subsequent pte tables have to be allocated in one physical
|
|
* chunk of RAM.
|
|
*/
|
|
#define PKMAP_BASE 0xfe000000UL
|
|
#define LAST_PKMAP 1024
|
|
#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
|
|
#define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT)
|
|
#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
|
|
|
|
extern unsigned long kmap_high(struct page *page);
|
|
extern void kunmap_high(struct page *page);
|
|
|
|
static inline unsigned long kmap(struct page *page)
|
|
{
|
|
if (in_interrupt())
|
|
BUG();
|
|
if (page < highmem_start_page)
|
|
return page_address(page);
|
|
return kmap_high(page);
|
|
}
|
|
|
|
static inline void kunmap(struct page *page)
|
|
{
|
|
if (in_interrupt())
|
|
BUG();
|
|
if (page < highmem_start_page)
|
|
return;
|
|
kunmap_high(page);
|
|
}
|
|
|
|
/*
|
|
* The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
|
|
* gives a more generic (and caching) interface. But kmap_atomic can
|
|
* be used in IRQ contexts, so in some (very limited) cases we need
|
|
* it.
|
|
*/
|
|
static inline unsigned long __kmap_atomic(struct page *page)
|
|
{
|
|
unsigned long vaddr;
|
|
int idx, type;
|
|
|
|
pagefault_disable();
|
|
if (page < highmem_start_page)
|
|
return page_address(page);
|
|
|
|
type = kmap_atomic_idx_push();
|
|
idx = type + KM_TYPE_NR * smp_processor_id();
|
|
vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
|
|
#if HIGHMEM_DEBUG
|
|
if (!pte_none(*(kmap_pte - idx)))
|
|
BUG();
|
|
#endif
|
|
set_pte(kmap_pte - idx, mk_pte(page, kmap_prot));
|
|
__flush_tlb_one(vaddr);
|
|
|
|
return vaddr;
|
|
}
|
|
|
|
static inline void __kunmap_atomic(unsigned long vaddr)
|
|
{
|
|
int type;
|
|
|
|
if (vaddr < FIXADDR_START) { /* FIXME */
|
|
pagefault_enable();
|
|
return;
|
|
}
|
|
|
|
type = kmap_atomic_idx_pop();
|
|
|
|
#if HIGHMEM_DEBUG
|
|
{
|
|
unsigned int idx;
|
|
idx = type + KM_TYPE_NR * smp_processor_id();
|
|
|
|
if (vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx))
|
|
BUG();
|
|
|
|
/*
|
|
* force other mappings to Oops if they'll try to access
|
|
* this pte without first remap it
|
|
*/
|
|
pte_clear(kmap_pte - idx);
|
|
__flush_tlb_one(vaddr);
|
|
}
|
|
#endif
|
|
pagefault_enable();
|
|
}
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* _ASM_HIGHMEM_H */
|