x86: unify pageattr_32.c and pageattr_64.c

unify the now perfectly identical pageattr_32/64.c files - no code changed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/mm/Makefile_32

@@ -2,7 +2,7 @@
 # Makefile for the linux i386-specific parts of the memory manager.
 #
 
-obj-y	:= init_32.o pgtable_32.o fault_32.o ioremap_32.o extable.o pageattr_32.o mmap.o
+obj-y	:= init_32.o pgtable_32.o fault_32.o ioremap_32.o extable.o pageattr.o mmap.o
 
 obj-$(CONFIG_CPA_DEBUG) += pageattr-test.o
 obj-$(CONFIG_NUMA) += discontig_32.o

arch/x86/mm/Makefile_64

@@ -2,7 +2,7 @@
 # Makefile for the linux x86_64-specific parts of the memory manager.
 #
 
-obj-y	 := init_64.o fault_64.o ioremap_64.o extable.o pageattr_64.o mmap.o
+obj-y	 := init_64.o fault_64.o ioremap_64.o extable.o pageattr.o mmap.o
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
 obj-$(CONFIG_NUMA) += numa_64.o
 obj-$(CONFIG_K8_NUMA) += k8topology_64.o

arch/x86/mm/pageattr_64.c

-/*
- * Copyright 2002 Andi Kleen, SuSE Labs.
- * Thanks to Ben LaHaise for precious feedback.
- */
-
-#include <linux/highmem.h>
-#include <linux/module.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/mm.h>
-
-#include <asm/processor.h>
-#include <asm/tlbflush.h>
-#include <asm/sections.h>
-#include <asm/uaccess.h>
-#include <asm/pgalloc.h>
-
-pte_t *lookup_address(unsigned long address, int *level)
-{
-	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;
-	*level = 3;
-	if (pmd_large(*pmd))
-		return (pte_t *)pmd;
-	*level = 4;
-
-	return pte_offset_kernel(pmd, address);
-}
-
-static void __set_pmd_pte(pte_t *kpte, unsigned long address, pte_t pte)
-{
-	/* change init_mm */
-	set_pte_atomic(kpte, pte);
-#ifdef CONFIG_X86_32
-	if (SHARED_KERNEL_PMD)
-		return;
-	{
-		struct page *page;
-
-		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);
-		}
-	}
-#endif
-}
-
-static int split_large_page(pte_t *kpte, unsigned long address)
-{
-	pgprot_t ref_prot = pte_pgprot(pte_clrhuge(*kpte));
-	gfp_t gfp_flags = GFP_KERNEL;
-	unsigned long flags;
-	unsigned long addr;
-	pte_t *pbase, *tmp;
-	struct page *base;
-	int i, level;
-
-
-#ifdef CONFIG_DEBUG_PAGEALLOC
-	gfp_flags = GFP_ATOMIC;
-#endif
-	base = alloc_pages(gfp_flags, 0);
-	if (!base)
-		return -ENOMEM;
-
-	spin_lock_irqsave(&pgd_lock, flags);
-	/*
-	 * Check for races, another CPU might have split this page
-	 * up for us already:
-	 */
-	tmp = lookup_address(address, &level);
-	if (tmp != kpte) {
-		WARN_ON_ONCE(1);
-		goto out_unlock;
-	}
-
-	address = __pa(address);
-	addr = address & LARGE_PAGE_MASK;
-	pbase = (pte_t *)page_address(base);
-#ifdef CONFIG_X86_32
-	paravirt_alloc_pt(&init_mm, page_to_pfn(base));
-#endif
-
-	for (i = 0; i < PTRS_PER_PTE; i++, addr += PAGE_SIZE)
-		set_pte(&pbase[i], pfn_pte(addr >> PAGE_SHIFT, ref_prot));
-
-	/*
-	 * Install the new, split up pagetable:
-	 */
-	__set_pmd_pte(kpte, address, mk_pte(base, ref_prot));
-	base = NULL;
-
-out_unlock:
-	spin_unlock_irqrestore(&pgd_lock, flags);
-
-	if (base)
-		__free_pages(base, 0);
-
-	return 0;
-}
-
-static int
-__change_page_attr(unsigned long address, struct page *page, pgprot_t prot)
-{
-	struct page *kpte_page;
-	int level, err = 0;
-	pte_t *kpte;
-
-	BUG_ON(PageHighMem(page));
-
-repeat:
-	kpte = lookup_address(address, &level);
-	if (!kpte)
-		return -EINVAL;
-
-	kpte_page = virt_to_page(kpte);
-	BUG_ON(PageLRU(kpte_page));
-	BUG_ON(PageCompound(kpte_page));
-
-	/*
-	 * Better fail early if someone sets the kernel text to NX.
-	 * Does not cover __inittext
-	 */
-	BUG_ON(address >= (unsigned long)&_text &&
-		address < (unsigned long)&_etext &&
-	       (pgprot_val(prot) & _PAGE_NX));
-
-	if (level == 4) {
-		set_pte_atomic(kpte, mk_pte(page, canon_pgprot(prot)));
-	} else {
-		err = split_large_page(kpte, address);
-		if (!err)
-			goto repeat;
-	}
-	return err;
-}
-
-/**
- * change_page_attr_addr - Change page table attributes in linear mapping
- * @address: Virtual address in linear mapping.
- * @numpages: Number of pages to change
- * @prot:    New page table attribute (PAGE_*)
- *
- * Change page attributes of a page in the direct mapping. This is a variant
- * of change_page_attr() that also works on memory holes that do not have
- * mem_map entry (pfn_valid() is false).
- *
- * See change_page_attr() documentation for more details.
- */
-
-int change_page_attr_addr(unsigned long address, int numpages, pgprot_t prot)
-{
-	int err = 0, kernel_map = 0, i;
-
-#ifdef CONFIG_X86_64
-	if (address >= __START_KERNEL_map &&
-			address < __START_KERNEL_map + KERNEL_TEXT_SIZE) {
-
-		address = (unsigned long)__va(__pa(address));
-		kernel_map = 1;
-	}
-#endif
-
-	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_to_page(pfn), prot);
-			if (err)
-				break;
-		}
-#ifdef CONFIG_X86_64
-		/*
-		 * Handle kernel mapping too which aliases part of
-		 * 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_to_page(pfn), prot2);
-		}
-#endif
-	}
-
-	return err;
-}
-
-/**
- * change_page_attr - Change page table attributes in the linear mapping.
- * @page: First page to change
- * @numpages: Number of pages to change
- * @prot: New protection/caching type (PAGE_*)
- *
- * Returns 0 on success, otherwise a negated errno.
- *
- * 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.
- *
- * Caller must call global_flush_tlb() later to make the changes active.
- *
- * The caller needs to ensure that there are no conflicting mappings elsewhere
- * (e.g. in user space) * This function only deals with the kernel linear map.
- *
- * For MMIO areas without mem_map use change_page_attr_addr() instead.
- */
-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);
-}
-EXPORT_SYMBOL(change_page_attr);
-
-static void flush_kernel_map(void *arg)
-{
-	/*
-	 * Flush all to work around Errata in early athlons regarding
-	 * large page flushing.
-	 */
-	__flush_tlb_all();
-
-	if (boot_cpu_data.x86_model >= 4)
-		wbinvd();
-}
-
-void global_flush_tlb(void)
-{
-	BUG_ON(irqs_disabled());
-
-	on_each_cpu(flush_kernel_map, NULL, 1, 1);
-}
-EXPORT_SYMBOL(global_flush_tlb);
-
-#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);
-	}
-
-	/*
-	 * If page allocator is not up yet then do not call c_p_a():
-	 */
-	if (!debug_pagealloc_enabled)
-		return;
-
-	/*
-	 * 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