summaryrefslogtreecommitdiffstats
path: root/arch/x86/mm/pageattr_64.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/mm/pageattr_64.c')
-rw-r--r--arch/x86/mm/pageattr_64.c255
1 files changed, 0 insertions, 255 deletions
diff --git a/arch/x86/mm/pageattr_64.c b/arch/x86/mm/pageattr_64.c
deleted file mode 100644
index c40afbaaf93d..000000000000
--- a/arch/x86/mm/pageattr_64.c
+++ /dev/null
@@ -1,255 +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/io.h>
-
-pte_t *lookup_address(unsigned long address)
-{
- pgd_t *pgd = pgd_offset_k(address);
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- if (pgd_none(*pgd))
- return NULL;
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return NULL;
- pmd = pmd_offset(pud, address);
- if (!pmd_present(*pmd))
- return NULL;
- if (pmd_large(*pmd))
- return (pte_t *)pmd;
- pte = pte_offset_kernel(pmd, address);
- if (pte && !pte_present(*pte))
- pte = NULL;
- return pte;
-}
-
-static struct page *split_large_page(unsigned long address, pgprot_t prot,
- pgprot_t ref_prot)
-{
- int i;
- unsigned long addr;
- struct page *base = alloc_pages(GFP_KERNEL, 0);
- pte_t *pbase;
- if (!base)
- return NULL;
- /*
- * page_private is used to track the number of entries in
- * the page table page have non standard attributes.
- */
- SetPagePrivate(base);
- page_private(base) = 0;
-
- address = __pa(address);
- addr = address & LARGE_PAGE_MASK;
- pbase = (pte_t *)page_address(base);
- for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE) {
- pbase[i] = pfn_pte(addr >> PAGE_SHIFT,
- addr == address ? prot : ref_prot);
- }
- return base;
-}
-
-void clflush_cache_range(void *adr, int size)
-{
- int i;
- for (i = 0; i < size; i += boot_cpu_data.x86_clflush_size)
- clflush(adr+i);
-}
-
-static void flush_kernel_map(void *arg)
-{
- struct list_head *l = (struct list_head *)arg;
- struct page *pg;
-
- /* When clflush is available always use it because it is
- much cheaper than WBINVD. */
- /* clflush is still broken. Disable for now. */
- if (1 || !cpu_has_clflush)
- asm volatile("wbinvd" ::: "memory");
- else list_for_each_entry(pg, l, lru) {
- void *adr = page_address(pg);
- clflush_cache_range(adr, PAGE_SIZE);
- }
- __flush_tlb_all();
-}
-
-static inline void flush_map(struct list_head *l)
-{
- on_each_cpu(flush_kernel_map, l, 1, 1);
-}
-
-static LIST_HEAD(deferred_pages); /* protected by init_mm.mmap_sem */
-
-static inline void save_page(struct page *fpage)
-{
- if (!test_and_set_bit(PG_arch_1, &fpage->flags))
- list_add(&fpage->lru, &deferred_pages);
-}
-
-/*
- * No more special protections in this 2/4MB area - revert to a
- * large page again.
- */
-static void revert_page(unsigned long address, pgprot_t ref_prot)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t large_pte;
- unsigned long pfn;
-
- pgd = pgd_offset_k(address);
- BUG_ON(pgd_none(*pgd));
- pud = pud_offset(pgd,address);
- BUG_ON(pud_none(*pud));
- pmd = pmd_offset(pud, address);
- BUG_ON(pmd_val(*pmd) & _PAGE_PSE);
- pfn = (__pa(address) & LARGE_PAGE_MASK) >> PAGE_SHIFT;
- large_pte = pfn_pte(pfn, ref_prot);
- large_pte = pte_mkhuge(large_pte);
- set_pte((pte_t *)pmd, large_pte);
-}
-
-static int
-__change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
- pgprot_t ref_prot)
-{
- pte_t *kpte;
- struct page *kpte_page;
- pgprot_t ref_prot2;
-
- kpte = lookup_address(address);
- if (!kpte) return 0;
- kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
- BUG_ON(PageLRU(kpte_page));
- BUG_ON(PageCompound(kpte_page));
- if (pgprot_val(prot) != pgprot_val(ref_prot)) {
- if (!pte_huge(*kpte)) {
- set_pte(kpte, pfn_pte(pfn, prot));
- } else {
- /*
- * split_large_page will take the reference for this
- * change_page_attr on the split page.
- */
- struct page *split;
- ref_prot2 = pte_pgprot(pte_clrhuge(*kpte));
- split = split_large_page(address, prot, ref_prot2);
- if (!split)
- return -ENOMEM;
- pgprot_val(ref_prot2) &= ~_PAGE_NX;
- set_pte(kpte, mk_pte(split, ref_prot2));
- kpte_page = split;
- }
- page_private(kpte_page)++;
- } else if (!pte_huge(*kpte)) {
- set_pte(kpte, pfn_pte(pfn, ref_prot));
- BUG_ON(page_private(kpte_page) == 0);
- page_private(kpte_page)--;
- } else
- BUG();
-
- /* on x86-64 the direct mapping set at boot is not using 4k pages */
- BUG_ON(PageReserved(kpte_page));
-
- save_page(kpte_page);
- if (page_private(kpte_page) == 0)
- revert_page(address, ref_prot);
- return 0;
-}
-
-/*
- * 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_addr(unsigned long address, int numpages, pgprot_t prot)
-{
- int err = 0, kernel_map = 0;
- int i;
-
- if (address >= __START_KERNEL_map
- && address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
- address = (unsigned long)__va(__pa(address));
- kernel_map = 1;
- }
-
- down_write(&init_mm.mmap_sem);
- for (i = 0; i < numpages; i++, address += PAGE_SIZE) {
- unsigned long pfn = __pa(address) >> PAGE_SHIFT;
-
- if (!kernel_map || pte_present(pfn_pte(0, prot))) {
- err = __change_page_attr(address, pfn, prot, PAGE_KERNEL);
- if (err)
- break;
- }
- /* Handle kernel mapping too which aliases part of the
- * lowmem */
- if (__pa(address) < KERNEL_TEXT_SIZE) {
- unsigned long addr2;
- pgprot_t prot2;
- addr2 = __START_KERNEL_map + __pa(address);
- /* Make sure the kernel mappings stay executable */
- prot2 = pte_pgprot(pte_mkexec(pfn_pte(0, prot)));
- err = __change_page_attr(addr2, pfn, prot2,
- PAGE_KERNEL_EXEC);
- }
- }
- up_write(&init_mm.mmap_sem);
- return err;
-}
-
-/* Don't call this for MMIO areas that may not have a mem_map entry */
-int change_page_attr(struct page *page, int numpages, pgprot_t prot)
-{
- unsigned long addr = (unsigned long)page_address(page);
- return change_page_attr_addr(addr, numpages, prot);
-}
-
-void global_flush_tlb(void)
-{
- struct page *pg, *next;
- struct list_head l;
-
- /*
- * Write-protect the semaphore, to exclude two contexts
- * doing a list_replace_init() call in parallel and to
- * exclude new additions to the deferred_pages list:
- */
- down_write(&init_mm.mmap_sem);
- list_replace_init(&deferred_pages, &l);
- up_write(&init_mm.mmap_sem);
-
- flush_map(&l);
-
- list_for_each_entry_safe(pg, next, &l, lru) {
- list_del(&pg->lru);
- clear_bit(PG_arch_1, &pg->flags);
- if (page_private(pg) != 0)
- continue;
- ClearPagePrivate(pg);
- __free_page(pg);
- }
-}
-
-EXPORT_SYMBOL(change_page_attr);
-EXPORT_SYMBOL(global_flush_tlb);