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author | Michal Simek <monstr@monstr.eu> | 2011-12-15 14:02:37 (GMT) |
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committer | Michal Simek <monstr@monstr.eu> | 2012-03-23 08:28:13 (GMT) |
commit | 2f2f371f8907d169650f594850ca6096e2f73b77 (patch) | |
tree | 053824b8bd18fdd71119510be569fa0ff7ec0c29 /arch/microblaze/include | |
parent | baab8a828d2d6b5b073c192ebe777514bbf3c831 (diff) | |
download | linux-2f2f371f8907d169650f594850ca6096e2f73b77.tar.xz |
microblaze: Highmem support
The first highmem implementation.
Signed-off-by: Michal Simek <monstr@monstr.eu>
Diffstat (limited to 'arch/microblaze/include')
-rw-r--r-- | arch/microblaze/include/asm/fixmap.h | 8 | ||||
-rw-r--r-- | arch/microblaze/include/asm/highmem.h | 96 |
2 files changed, 104 insertions, 0 deletions
diff --git a/arch/microblaze/include/asm/fixmap.h b/arch/microblaze/include/asm/fixmap.h index dd89754..f2b312e 100644 --- a/arch/microblaze/include/asm/fixmap.h +++ b/arch/microblaze/include/asm/fixmap.h @@ -21,6 +21,10 @@ #ifndef __ASSEMBLY__ #include <linux/kernel.h> #include <asm/page.h> +#ifdef CONFIG_HIGHMEM +#include <linux/threads.h> +#include <asm/kmap_types.h> +#endif #define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE)) @@ -44,6 +48,10 @@ */ enum fixed_addresses { FIX_HOLE, +#ifdef CONFIG_HIGHMEM + FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ + FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * num_possible_cpus()) - 1, +#endif __end_of_fixed_addresses }; diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h new file mode 100644 index 0000000..2446a73 --- /dev/null +++ b/arch/microblaze/include/asm/highmem.h @@ -0,0 +1,96 @@ +/* + * highmem.h: virtual kernel memory mappings for high memory + * + * 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 Terabyte 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 <linux/uaccess.h> +#include <asm/fixmap.h> + +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. + */ +/* + * We use one full pte table with 4K pages. And with 16K/64K/256K pages pte + * table covers enough memory (32MB/512MB/2GB resp.), so that both FIXMAP + * and PKMAP can be placed in a single pte table. We use 512 pages for PKMAP + * in case of 16K/64K/256K page sizes. + */ + +#define PKMAP_ORDER PTE_SHIFT +#define LAST_PKMAP (1 << PKMAP_ORDER) + +#define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE * (LAST_PKMAP + 1)) \ + & PMD_MASK) + +#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 void *kmap_high(struct page *page); +extern void kunmap_high(struct page *page); +extern void *kmap_atomic_prot(struct page *page, pgprot_t prot); +extern void __kunmap_atomic(void *kvaddr); + +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); +} + +static inline void *__kmap_atomic(struct page *page) +{ + return kmap_atomic_prot(page, kmap_prot); +} + +static inline struct page *kmap_atomic_to_page(void *ptr) +{ + unsigned long idx, vaddr = (unsigned long) ptr; + pte_t *pte; + + if (vaddr < FIXADDR_START) + return virt_to_page(ptr); + + idx = virt_to_fix(vaddr); + pte = kmap_pte - (idx - FIX_KMAP_BEGIN); + return pte_page(*pte); +} + +#define flush_cache_kmaps() { flush_icache(); flush_dcache(); } + +#endif /* __KERNEL__ */ + +#endif /* _ASM_HIGHMEM_H */ |