diff options
author | Dave Hansen <dave.hansen@linux.intel.com> | 2016-02-12 13:02:10 -0800 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2016-02-18 09:31:51 +0100 |
commit | 8f62c883222c9e3c06d60b5e55e307a3d1f18257 (patch) | |
tree | 7b9a6263f7232ebc49bfeae15668b198d1a0b032 /arch/x86/include/asm/pgtable_types.h | |
parent | 63c17fb8e5a46a16e10e82005748837fd11a2024 (diff) | |
download | linux-stable-8f62c883222c9e3c06d60b5e55e307a3d1f18257.tar.gz linux-stable-8f62c883222c9e3c06d60b5e55e307a3d1f18257.tar.bz2 linux-stable-8f62c883222c9e3c06d60b5e55e307a3d1f18257.zip |
x86/mm/pkeys: Add arch-specific VMA protection bits
Lots of things seem to do:
vma->vm_page_prot = vm_get_page_prot(flags);
and the ptes get created right from things we pull out
of ->vm_page_prot. So it is very convenient if we can
store the protection key in flags and vm_page_prot, just
like the existing permission bits (_PAGE_RW/PRESENT). It
greatly reduces the amount of plumbing and arch-specific
hacking we have to do in generic code.
This also takes the new PROT_PKEY{0,1,2,3} flags and
turns *those* in to VM_ flags for vma->vm_flags.
The protection key values are stored in 4 places:
1. "prot" argument to system calls
2. vma->vm_flags, filled from the mmap "prot"
3. vma->vm_page prot, filled from vma->vm_flags
4. the PTE itself.
The pseudocode for these for steps are as follows:
mmap(PROT_PKEY*)
vma->vm_flags = ... | arch_calc_vm_prot_bits(mmap_prot);
vma->vm_page_prot = ... | arch_vm_get_page_prot(vma->vm_flags);
pte = pfn | vma->vm_page_prot
Note that this provides a new definitions for x86:
arch_vm_get_page_prot()
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20160212210210.FE483A42@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/include/asm/pgtable_types.h')
-rw-r--r-- | arch/x86/include/asm/pgtable_types.h | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index cae10ba3c975..8c35cf0cc2ef 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -115,7 +115,12 @@ #define _KERNPG_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | \ _PAGE_DIRTY) -/* Set of bits not changed in pte_modify */ +/* + * Set of bits not changed in pte_modify. The pte's + * protection key is treated like _PAGE_RW, for + * instance, and is *not* included in this mask since + * pte_modify() does modify it. + */ #define _PAGE_CHG_MASK (PTE_PFN_MASK | _PAGE_PCD | _PAGE_PWT | \ _PAGE_SPECIAL | _PAGE_ACCESSED | _PAGE_DIRTY | \ _PAGE_SOFT_DIRTY) @@ -231,7 +236,10 @@ enum page_cache_mode { /* Extracts the PFN from a (pte|pmd|pud|pgd)val_t of a 4KB page */ #define PTE_PFN_MASK ((pteval_t)PHYSICAL_PAGE_MASK) -/* Extracts the flags from a (pte|pmd|pud|pgd)val_t of a 4KB page */ +/* + * Extracts the flags from a (pte|pmd|pud|pgd)val_t + * This includes the protection key value. + */ #define PTE_FLAGS_MASK (~PTE_PFN_MASK) typedef struct pgprot { pgprotval_t pgprot; } pgprot_t; |