diff options
Diffstat (limited to 'arch/parisc/kernel/cache.c')
| -rw-r--r-- | arch/parisc/kernel/cache.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/parisc/kernel/cache.c b/arch/parisc/kernel/cache.c index ec63de95cbd9..1c61b8245650 100644 --- a/arch/parisc/kernel/cache.c +++ b/arch/parisc/kernel/cache.c @@ -596,3 +596,67 @@ flush_cache_page(struct vm_area_struct *vma, unsigned long vmaddr, unsigned long __flush_cache_page(vma, vmaddr, page_to_phys(pfn_to_page(pfn))); } + +#ifdef CONFIG_PARISC_TMPALIAS + +void clear_user_highpage(struct page *page, unsigned long vaddr) +{ + void *vto; + unsigned long flags; + + /* Clear using TMPALIAS region. The page doesn't need to + be flushed but the kernel mapping needs to be purged. */ + + vto = kmap_atomic(page, KM_USER0); + + /* The PA-RISC 2.0 Architecture book states on page F-6: + "Before a write-capable translation is enabled, *all* + non-equivalently-aliased translations must be removed + from the page table and purged from the TLB. (Note + that the caches are not required to be flushed at this + time.) Before any non-equivalent aliased translation + is re-enabled, the virtual address range for the writeable + page (the entire page) must be flushed from the cache, + and the write-capable translation removed from the page + table and purged from the TLB." */ + + purge_kernel_dcache_page_asm((unsigned long)vto); + purge_tlb_start(flags); + pdtlb_kernel(vto); + purge_tlb_end(flags); + preempt_disable(); + clear_user_page_asm(vto, vaddr); + preempt_enable(); + + pagefault_enable(); /* kunmap_atomic(addr, KM_USER0); */ +} + +void copy_user_highpage(struct page *to, struct page *from, + unsigned long vaddr, struct vm_area_struct *vma) +{ + void *vfrom, *vto; + unsigned long flags; + + /* Copy using TMPALIAS region. This has the advantage + that the `from' page doesn't need to be flushed. However, + the `to' page must be flushed in copy_user_page_asm since + it can be used to bring in executable code. */ + + vfrom = kmap_atomic(from, KM_USER0); + vto = kmap_atomic(to, KM_USER1); + + purge_kernel_dcache_page_asm((unsigned long)vto); + purge_tlb_start(flags); + pdtlb_kernel(vto); + pdtlb_kernel(vfrom); + purge_tlb_end(flags); + preempt_disable(); + copy_user_page_asm(vto, vfrom, vaddr); + flush_dcache_page_asm(__pa(vto), vaddr); + preempt_enable(); + + pagefault_enable(); /* kunmap_atomic(addr, KM_USER1); */ + pagefault_enable(); /* kunmap_atomic(addr, KM_USER0); */ +} + +#endif /* CONFIG_PARISC_TMPALIAS */ |