diff options
Diffstat (limited to 'arch/sh/mm/pg-mmu.c')
-rw-r--r-- | arch/sh/mm/pg-mmu.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/arch/sh/mm/pg-mmu.c b/arch/sh/mm/pg-mmu.c new file mode 100644 index 00000000000..356d2cdcb20 --- /dev/null +++ b/arch/sh/mm/pg-mmu.c @@ -0,0 +1,136 @@ +/* + * arch/sh/mm/pg-mmu.c + * + * Copyright (C) 1999, 2000, 2002 Niibe Yutaka + * Copyright (C) 2002 - 2009 Paul Mundt + * + * Released under the terms of the GNU GPL v2.0. + */ +#include <linux/mm.h> +#include <linux/init.h> +#include <linux/mutex.h> +#include <linux/fs.h> +#include <linux/highmem.h> +#include <linux/module.h> +#include <asm/mmu_context.h> +#include <asm/cacheflush.h> + +#define kmap_get_fixmap_pte(vaddr) \ + pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)), (vaddr)), (vaddr)) + +static pte_t *kmap_coherent_pte; + +void __init kmap_coherent_init(void) +{ +#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB) + unsigned long vaddr; + + /* cache the first coherent kmap pte */ + vaddr = __fix_to_virt(FIX_CMAP_BEGIN); + kmap_coherent_pte = kmap_get_fixmap_pte(vaddr); +#endif +} + +static inline void *kmap_coherent(struct page *page, unsigned long addr) +{ + enum fixed_addresses idx; + unsigned long vaddr, flags; + pte_t pte; + + inc_preempt_count(); + + idx = (addr & current_cpu_data.dcache.alias_mask) >> PAGE_SHIFT; + vaddr = __fix_to_virt(FIX_CMAP_END - idx); + pte = mk_pte(page, PAGE_KERNEL); + + local_irq_save(flags); + flush_tlb_one(get_asid(), vaddr); + local_irq_restore(flags); + + update_mmu_cache(NULL, vaddr, pte); + + set_pte(kmap_coherent_pte - (FIX_CMAP_END - idx), pte); + + return (void *)vaddr; +} + +static inline void kunmap_coherent(struct page *page) +{ + dec_preempt_count(); + preempt_check_resched(); +} + +void copy_to_user_page(struct vm_area_struct *vma, struct page *page, + unsigned long vaddr, void *dst, const void *src, + unsigned long len) +{ + if (boot_cpu_data.dcache.n_aliases && page_mapped(page) && + !test_bit(PG_dcache_dirty, &page->flags)) { + void *vto = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); + memcpy(vto, src, len); + kunmap_coherent(vto); + } else { + memcpy(dst, src, len); + if (boot_cpu_data.dcache.n_aliases) + set_bit(PG_dcache_dirty, &page->flags); + } + + if (vma->vm_flags & VM_EXEC) + flush_cache_page(vma, vaddr, page_to_pfn(page)); +} + +void copy_from_user_page(struct vm_area_struct *vma, struct page *page, + unsigned long vaddr, void *dst, const void *src, + unsigned long len) +{ + if (boot_cpu_data.dcache.n_aliases && page_mapped(page) && + !test_bit(PG_dcache_dirty, &page->flags)) { + void *vfrom = kmap_coherent(page, vaddr) + (vaddr & ~PAGE_MASK); + memcpy(dst, vfrom, len); + kunmap_coherent(vfrom); + } else { + memcpy(dst, src, len); + if (boot_cpu_data.dcache.n_aliases) + set_bit(PG_dcache_dirty, &page->flags); + } +} + +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + void *vfrom, *vto; + + vto = kmap_atomic(to, KM_USER1); + + if (boot_cpu_data.dcache.n_aliases && page_mapped(from) && + !test_bit(PG_dcache_dirty, &from->flags)) { + vfrom = kmap_coherent(from, vaddr); + copy_page(vto, vfrom); + kunmap_coherent(vfrom); + } else { + vfrom = kmap_atomic(from, KM_USER0); + copy_page(vto, vfrom); + kunmap_atomic(vfrom, KM_USER0); + } + + if (pages_do_alias((unsigned long)vto, vaddr & PAGE_MASK)) + __flush_wback_region(vto, PAGE_SIZE); + + kunmap_atomic(vto, KM_USER1); + /* Make sure this page is cleared on other CPU's too before using it */ + smp_wmb(); +} +EXPORT_SYMBOL(copy_user_highpage); + +void clear_user_highpage(struct page *page, unsigned long vaddr) +{ + void *kaddr = kmap_atomic(page, KM_USER0); + + clear_page(kaddr); + + if (pages_do_alias((unsigned long)kaddr, vaddr & PAGE_MASK)) + __flush_wback_region(kaddr, PAGE_SIZE); + + kunmap_atomic(kaddr, KM_USER0); +} +EXPORT_SYMBOL(clear_user_highpage); |