diff options
Diffstat (limited to 'arch/x86/mm/pageattr_32.c')
-rw-r--r-- | arch/x86/mm/pageattr_32.c | 278 |
1 files changed, 0 insertions, 278 deletions
diff --git a/arch/x86/mm/pageattr_32.c b/arch/x86/mm/pageattr_32.c deleted file mode 100644 index 260073c..0000000 --- a/arch/x86/mm/pageattr_32.c +++ /dev/null @@ -1,278 +0,0 @@ -/* - * Copyright 2002 Andi Kleen, SuSE Labs. - * Thanks to Ben LaHaise for precious feedback. - */ - -#include <linux/mm.h> -#include <linux/sched.h> -#include <linux/highmem.h> -#include <linux/module.h> -#include <linux/slab.h> -#include <asm/uaccess.h> -#include <asm/processor.h> -#include <asm/tlbflush.h> -#include <asm/pgalloc.h> -#include <asm/sections.h> - -static DEFINE_SPINLOCK(cpa_lock); -static struct list_head df_list = LIST_HEAD_INIT(df_list); - - -pte_t *lookup_address(unsigned long address) -{ - pgd_t *pgd = pgd_offset_k(address); - pud_t *pud; - pmd_t *pmd; - if (pgd_none(*pgd)) - return NULL; - pud = pud_offset(pgd, address); - if (pud_none(*pud)) - return NULL; - pmd = pmd_offset(pud, address); - if (pmd_none(*pmd)) - return NULL; - if (pmd_large(*pmd)) - return (pte_t *)pmd; - return pte_offset_kernel(pmd, address); -} - -static struct page *split_large_page(unsigned long address, pgprot_t prot, - pgprot_t ref_prot) -{ - int i; - unsigned long addr; - struct page *base; - pte_t *pbase; - - spin_unlock_irq(&cpa_lock); - base = alloc_pages(GFP_KERNEL, 0); - spin_lock_irq(&cpa_lock); - if (!base) - return NULL; - - /* - * page_private is used to track the number of entries in - * the page table page that have non standard attributes. - */ - SetPagePrivate(base); - page_private(base) = 0; - - address = __pa(address); - addr = address & LARGE_PAGE_MASK; - pbase = (pte_t *)page_address(base); - paravirt_alloc_pt(&init_mm, page_to_pfn(base)); - for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) { - set_pte(&pbase[i], pfn_pte(addr >> PAGE_SHIFT, - addr == address ? prot : ref_prot)); - } - return base; -} - -static void cache_flush_page(struct page *p) -{ - void *adr = page_address(p); - int i; - for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size) - clflush(adr+i); -} - -static void flush_kernel_map(void *arg) -{ - struct list_head *lh = (struct list_head *)arg; - struct page *p; - - /* High level code is not ready for clflush yet */ - if (0 && cpu_has_clflush) { - list_for_each_entry (p, lh, lru) - cache_flush_page(p); - } else if (boot_cpu_data.x86_model >= 4) - wbinvd(); - - /* Flush all to work around Errata in early athlons regarding - * large page flushing. - */ - __flush_tlb_all(); -} - -static void set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte) -{ - struct page *page; - unsigned long flags; - - set_pte_atomic(kpte, pte); /* change init_mm */ - if (SHARED_KERNEL_PMD) - return; - - spin_lock_irqsave(&pgd_lock, flags); - for (page = pgd_list; page; page = (struct page *)page->index) { - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pgd = (pgd_t *)page_address(page) + pgd_index(address); - pud = pud_offset(pgd, address); - pmd = pmd_offset(pud, address); - set_pte_atomic((pte_t *)pmd, pte); - } - spin_unlock_irqrestore(&pgd_lock, flags); -} - -/* - * No more special protections in this 2/4MB area - revert to a - * large page again. - */ -static inline void revert_page(struct page *kpte_page, unsigned long address) -{ - pgprot_t ref_prot; - pte_t *linear; - - ref_prot = - ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext) - ? PAGE_KERNEL_LARGE_EXEC : PAGE_KERNEL_LARGE; - - linear = (pte_t *) - pmd_offset(pud_offset(pgd_offset_k(address), address), address); - set_pmd_pte(linear, address, - pfn_pte((__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT, - ref_prot)); -} - -static inline void save_page(struct page *kpte_page) -{ - if (!test_and_set_bit(PG_arch_1, &kpte_page->flags)) - list_add(&kpte_page->lru, &df_list); -} - -static int -__change_page_attr(struct page *page, pgprot_t prot) -{ - pte_t *kpte; - unsigned long address; - struct page *kpte_page; - - BUG_ON(PageHighMem(page)); - address = (unsigned long)page_address(page); - - kpte = lookup_address(address); - if (!kpte) - return -EINVAL; - kpte_page = virt_to_page(kpte); - BUG_ON(PageLRU(kpte_page)); - BUG_ON(PageCompound(kpte_page)); - - if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) { - if (!pte_huge(*kpte)) { - set_pte_atomic(kpte, mk_pte(page, prot)); - } else { - pgprot_t ref_prot; - struct page *split; - - ref_prot = - ((address & LARGE_PAGE_MASK) < (unsigned long)&_etext) - ? PAGE_KERNEL_EXEC : PAGE_KERNEL; - split = split_large_page(address, prot, ref_prot); - if (!split) - return -ENOMEM; - set_pmd_pte(kpte,address,mk_pte(split, ref_prot)); - kpte_page = split; - } - page_private(kpte_page)++; - } else if (!pte_huge(*kpte)) { - set_pte_atomic(kpte, mk_pte(page, PAGE_KERNEL)); - BUG_ON(page_private(kpte_page) == 0); - page_private(kpte_page)--; - } else - BUG(); - - /* - * If the pte was reserved, it means it was created at boot - * time (not via split_large_page) and in turn we must not - * replace it with a largepage. - */ - - save_page(kpte_page); - if (!PageReserved(kpte_page)) { - if (cpu_has_pse && (page_private(kpte_page) == 0)) { - paravirt_release_pt(page_to_pfn(kpte_page)); - revert_page(kpte_page, address); - } - } - return 0; -} - -static inline void flush_map(struct list_head *l) -{ - on_each_cpu(flush_kernel_map, l, 1, 1); -} - -/* - * Change the page attributes of an page in the linear mapping. - * - * This should be used when a page is mapped with a different caching policy - * than write-back somewhere - some CPUs do not like it when mappings with - * different caching policies exist. This changes the page attributes of the - * in kernel linear mapping too. - * - * The caller needs to ensure that there are no conflicting mappings elsewhere. - * This function only deals with the kernel linear map. - * - * Caller must call global_flush_tlb() after this. - */ -int change_page_attr(struct page *page, int numpages, pgprot_t prot) -{ - int err = 0; - int i; - unsigned long flags; - - spin_lock_irqsave(&cpa_lock, flags); - for (i = 0; i < numpages; i++, page++) { - err = __change_page_attr(page, prot); - if (err) - break; - } - spin_unlock_irqrestore(&cpa_lock, flags); - return err; -} - -void global_flush_tlb(void) -{ - struct list_head l; - struct page *pg, *next; - - BUG_ON(irqs_disabled()); - - spin_lock_irq(&cpa_lock); - list_replace_init(&df_list, &l); - spin_unlock_irq(&cpa_lock); - flush_map(&l); - list_for_each_entry_safe(pg, next, &l, lru) { - list_del(&pg->lru); - clear_bit(PG_arch_1, &pg->flags); - if (PageReserved(pg) || !cpu_has_pse || page_private(pg) != 0) - continue; - ClearPagePrivate(pg); - __free_page(pg); - } -} - -#ifdef CONFIG_DEBUG_PAGEALLOC -void kernel_map_pages(struct page *page, int numpages, int enable) -{ - if (PageHighMem(page)) - return; - if (!enable) - debug_check_no_locks_freed(page_address(page), - numpages * PAGE_SIZE); - - /* the return value is ignored - the calls cannot fail, - * large pages are disabled at boot time. - */ - change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0)); - /* we should perform an IPI and flush all tlbs, - * but that can deadlock->flush only current cpu. - */ - __flush_tlb_all(); -} -#endif - -EXPORT_SYMBOL(change_page_attr); -EXPORT_SYMBOL(global_flush_tlb); |