mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-15 00:04:15 +08:00
33d71d26ba
To build arch/powerpc without including asm-ppc/ we need these files in asm-powerpc/ Moved some headers under arch/powerpc/platforms if they were only used by platform or driver files and fixed up the source file includes to match the new locations Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
136 lines
3.3 KiB
C
136 lines
3.3 KiB
C
/*
|
|
* highmem.h: virtual kernel memory mappings for high memory
|
|
*
|
|
* PowerPC version, stolen from the i386 version.
|
|
*
|
|
* Used in CONFIG_HIGHMEM systems for memory pages which
|
|
* are not addressable by direct kernel virtual addresses.
|
|
*
|
|
* Copyright (C) 1999 Gerhard Wichert, Siemens AG
|
|
* Gerhard.Wichert@pdb.siemens.de
|
|
*
|
|
*
|
|
* Redesigned the x86 32-bit VM architecture to deal with
|
|
* up to 16 Terrabyte physical memory. With current x86 CPUs
|
|
* we now support up to 64 Gigabytes physical RAM.
|
|
*
|
|
* Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
|
|
*/
|
|
|
|
#ifndef _ASM_HIGHMEM_H
|
|
#define _ASM_HIGHMEM_H
|
|
|
|
#ifdef __KERNEL__
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <asm/kmap_types.h>
|
|
#include <asm/tlbflush.h>
|
|
#include <asm/page.h>
|
|
|
|
/* undef for production */
|
|
#define HIGHMEM_DEBUG 1
|
|
|
|
extern pte_t *kmap_pte;
|
|
extern pgprot_t kmap_prot;
|
|
extern pte_t *pkmap_page_table;
|
|
|
|
/*
|
|
* 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 CONFIG_HIGHMEM_START
|
|
#define LAST_PKMAP (1 << PTE_SHIFT)
|
|
#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))
|
|
|
|
#define KMAP_FIX_BEGIN (PKMAP_BASE + 0x00400000UL)
|
|
|
|
extern void *kmap_high(struct page *page);
|
|
extern void kunmap_high(struct page *page);
|
|
|
|
static inline void *kmap(struct page *page)
|
|
{
|
|
might_sleep();
|
|
if (!PageHighMem(page))
|
|
return page_address(page);
|
|
return kmap_high(page);
|
|
}
|
|
|
|
static inline void kunmap(struct page *page)
|
|
{
|
|
BUG_ON(in_interrupt());
|
|
if (!PageHighMem(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 void *kmap_atomic(struct page *page, enum km_type type)
|
|
{
|
|
unsigned int idx;
|
|
unsigned long vaddr;
|
|
|
|
/* even !CONFIG_PREEMPT needs this, for in_atomic in do_page_fault */
|
|
pagefault_disable();
|
|
if (!PageHighMem(page))
|
|
return page_address(page);
|
|
|
|
idx = type + KM_TYPE_NR*smp_processor_id();
|
|
vaddr = KMAP_FIX_BEGIN + idx * PAGE_SIZE;
|
|
#ifdef HIGHMEM_DEBUG
|
|
BUG_ON(!pte_none(*(kmap_pte+idx)));
|
|
#endif
|
|
set_pte_at(&init_mm, vaddr, kmap_pte+idx, mk_pte(page, kmap_prot));
|
|
flush_tlb_page(NULL, vaddr);
|
|
|
|
return (void*) vaddr;
|
|
}
|
|
|
|
static inline void kunmap_atomic(void *kvaddr, enum km_type type)
|
|
{
|
|
#ifdef HIGHMEM_DEBUG
|
|
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
|
|
unsigned int idx = type + KM_TYPE_NR*smp_processor_id();
|
|
|
|
if (vaddr < KMAP_FIX_BEGIN) { // FIXME
|
|
pagefault_enable();
|
|
return;
|
|
}
|
|
|
|
BUG_ON(vaddr != KMAP_FIX_BEGIN + idx * PAGE_SIZE);
|
|
|
|
/*
|
|
* force other mappings to Oops if they'll try to access
|
|
* this pte without first remap it
|
|
*/
|
|
pte_clear(&init_mm, vaddr, kmap_pte+idx);
|
|
flush_tlb_page(NULL, vaddr);
|
|
#endif
|
|
pagefault_enable();
|
|
}
|
|
|
|
static inline struct page *kmap_atomic_to_page(void *ptr)
|
|
{
|
|
unsigned long idx, vaddr = (unsigned long) ptr;
|
|
|
|
if (vaddr < KMAP_FIX_BEGIN)
|
|
return virt_to_page(ptr);
|
|
|
|
idx = (vaddr - KMAP_FIX_BEGIN) >> PAGE_SHIFT;
|
|
return pte_page(kmap_pte[idx]);
|
|
}
|
|
|
|
#define flush_cache_kmaps() flush_cache_all()
|
|
|
|
#endif /* __KERNEL__ */
|
|
|
|
#endif /* _ASM_HIGHMEM_H */
|