From 55f98f1a26ff6cbed6189ec90143cc5c428d5b78 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 11 Oct 2007 11:13:56 +0200 Subject: i386: prepare shared mm/pageattr.c Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar diff --git a/arch/i386/mm/Makefile b/arch/i386/mm/Makefile index 2c81ad1..4d7c5af 100644 --- a/arch/i386/mm/Makefile +++ b/arch/i386/mm/Makefile @@ -2,7 +2,7 @@ # Makefile for the linux i386-specific parts of the memory manager. # -obj-y := init_32.o pgtable_32.o fault.o ioremap_32.o extable_32.o pageattr.o mmap_32.o +obj-y := init_32.o pgtable_32.o fault.o ioremap_32.o extable_32.o pageattr_32.o mmap_32.o obj-$(CONFIG_NUMA) += discontig_32.o obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o diff --git a/arch/i386/mm/pageattr.c b/arch/i386/mm/pageattr.c deleted file mode 100644 index 4241a74..0000000 --- a/arch/i386/mm/pageattr.c +++ /dev/null @@ -1,278 +0,0 @@ -/* - * Copyright 2002 Andi Kleen, SuSE Labs. - * Thanks to Ben LaHaise for precious feedback. - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -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) -{ - unsigned long adr = (unsigned long)page_address(p); - int i; - for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size) - asm volatile("clflush (%0)" :: "r" (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); diff --git a/arch/i386/mm/pageattr_32.c b/arch/i386/mm/pageattr_32.c new file mode 100644 index 0000000..4241a74 --- /dev/null +++ b/arch/i386/mm/pageattr_32.c @@ -0,0 +1,278 @@ +/* + * Copyright 2002 Andi Kleen, SuSE Labs. + * Thanks to Ben LaHaise for precious feedback. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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) +{ + unsigned long adr = (unsigned long)page_address(p); + int i; + for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size) + asm volatile("clflush (%0)" :: "r" (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); -- cgit v0.10.2