linux-sg2042/arch/x86/include/asm/page.h

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#ifndef _ASM_X86_PAGE_H
#define _ASM_X86_PAGE_H
#include <linux/types.h>
#ifdef __KERNEL__
#include <asm/page_types.h>
#ifdef CONFIG_X86_64
#include <asm/page_64.h>
#else
#include <asm/page_32.h>
#endif /* CONFIG_X86_64 */
#ifndef __ASSEMBLY__
struct page;
#include <linux/range.h>
extern struct range pfn_mapped[];
extern int nr_pfn_mapped;
static inline void clear_user_page(void *page, unsigned long vaddr,
struct page *pg)
{
clear_page(page);
}
static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
struct page *topage)
{
copy_page(to, from);
}
#define __alloc_zeroed_user_highpage(movableflags, vma, vaddr) \
alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
#define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
#ifndef __pa
#define __pa(x) __phys_addr((unsigned long)(x))
#endif
#define __pa_nodebug(x) __phys_addr_nodebug((unsigned long)(x))
/* __pa_symbol should be used for C visible symbols.
This seems to be the official gcc blessed way to do such arithmetic. */
/*
* We need __phys_reloc_hide() here because gcc may assume that there is no
* overflow during __pa() calculation and can optimize it unexpectedly.
* Newer versions of gcc provide -fno-strict-overflow switch to handle this
* case properly. Once all supported versions of gcc understand it, we can
* remove this Voodoo magic stuff. (i.e. once gcc3.x is deprecated)
*/
#define __pa_symbol(x) \
__phys_addr_symbol(__phys_reloc_hide((unsigned long)(x)))
#ifndef __va
#define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET))
#endif
#define __boot_va(x) __va(x)
#define __boot_pa(x) __pa(x)
/*
* virt_to_page(kaddr) returns a valid pointer if and only if
* virt_addr_valid(kaddr) returns true.
*/
#define virt_to_page(kaddr) pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
#define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT)
extern bool __virt_addr_valid(unsigned long kaddr);
#define virt_addr_valid(kaddr) __virt_addr_valid((unsigned long) (kaddr))
#endif /* __ASSEMBLY__ */
#include <asm-generic/memory_model.h>
#include <asm-generic/getorder.h>
x86/mm: Implement ASLR for hugetlb mappings Matthew noticed that hugetlb mappings don't participate in ASLR on x86-64: % for i in `seq 3`; do > tools/testing/selftests/vm/map_hugetlb | grep address > done Returned address is 0x2aaaaac00000 Returned address is 0x2aaaaac00000 Returned address is 0x2aaaaac00000 /proc/PID/maps entries for the mapping are always the same (except inode number): 2aaaaac00000-2aaabac00000 rw-p 00000000 00:0c 8200 /anon_hugepage (deleted) 2aaaaac00000-2aaabac00000 rw-p 00000000 00:0c 256 /anon_hugepage (deleted) 2aaaaac00000-2aaabac00000 rw-p 00000000 00:0c 7180 /anon_hugepage (deleted) The reason is the generic hugetlb_get_unmapped_area() function which is used on x86-64. It doesn't support randomization and use bottom-up unmapped area lookup, instead of usual top-down on x86-64. x86 has arch-specific hugetlb_get_unmapped_area(), but it's used only on x86-32. Let's use arch-specific hugetlb_get_unmapped_area() on x86-64 too. That adds ASLR and switches hugetlb mappings to use top-down unmapped area lookup: % for i in `seq 3`; do > tools/testing/selftests/vm/map_hugetlb | grep address > done Returned address is 0x7f4f08a00000 Returned address is 0x7fdda4200000 Returned address is 0x7febe0000000 /proc/PID/maps entries: 7f4f08a00000-7f4f18a00000 rw-p 00000000 00:0c 1168 /anon_hugepage (deleted) 7fdda4200000-7fddb4200000 rw-p 00000000 00:0c 7092 /anon_hugepage (deleted) 7febe0000000-7febf0000000 rw-p 00000000 00:0c 7183 /anon_hugepage (deleted) Unmapped area lookup policy for hugetlb mappings is consistent with normal mappings now -- the only difference is alignment requirements for huge pages. libhugetlbfs test-suite didn't detect any regressions with the patch applied (although it shows few failures on my machine regardless the patch). Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mel Gorman <mgorman@suse.de> Link: http://lkml.kernel.org/r/20131119131750.EA45CE0090@blue.fi.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-11-19 21:17:50 +08:00
#define HAVE_ARCH_HUGETLB_UNMAPPED_AREA
#endif /* __KERNEL__ */
#endif /* _ASM_X86_PAGE_H */