korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-23 11:04:44 +08:00
Code Issues Packages Projects Releases Wiki Activity
2864697cef
linux/arch/powerpc/include/asm/pgtable-ppc64.h
Benjamin Herrenschmidt ea3cc330ac powerpc/mm: Cleanup handling of execute permission 
This is an attempt at cleaning up a bit the way we handle execute
permission on powerpc. _PAGE_HWEXEC is gone, _PAGE_EXEC is now only
defined by CPUs that can do something with it, and the myriad of
#ifdef's in the I$/D$ coherency code is reduced to 2 cases that
hopefully should cover everything.

The logic on BookE is a little bit different than what it was though
not by much. Since now, _PAGE_EXEC will be set by the generic code
for executable pages, we need to filter out if they are unclean and
recover it. However, I don't expect the code to be more bloated than
it already was in that area due to that change.

I could boast that this brings proper enforcing of per-page execute
permissions to all BookE and 40x but in fact, we've had that now for
some time as a side effect of my previous rework in that area (and
I didn't even know it :-) We would only enable execute permission if
the page was cache clean and we would only cache clean it if we took
and exec fault. Since we now enforce that the later only work if
VM_EXEC is part of the VMA flags, we de-fact already enforce per-page
execute permissions... Unless I missed something

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:12:51 +10:00

386 lines
11 KiB
C
Raw Blame History

#ifndef _ASM_POWERPC_PGTABLE_PPC64_H_
#define _ASM_POWERPC_PGTABLE_PPC64_H_
/*
* This file contains the functions and defines necessary to modify and use
* the ppc64 hashed page table.
*/
#ifdef CONFIG_PPC_64K_PAGES
#include <asm/pgtable-ppc64-64k.h>
#else
#include <asm/pgtable-ppc64-4k.h>
#endif
#define FIRST_USER_ADDRESS 0
/*
* Size of EA range mapped by our pagetables.
*/
#define PGTABLE_EADDR_SIZE (PTE_INDEX_SIZE + PMD_INDEX_SIZE + \
PUD_INDEX_SIZE + PGD_INDEX_SIZE + PAGE_SHIFT)
#define PGTABLE_RANGE (ASM_CONST(1) << PGTABLE_EADDR_SIZE)
/* Some sanity checking */
#if TASK_SIZE_USER64 > PGTABLE_RANGE
#error TASK_SIZE_USER64 exceeds pagetable range
#endif
#ifdef CONFIG_PPC_STD_MMU_64
#if TASK_SIZE_USER64 > (1UL << (USER_ESID_BITS + SID_SHIFT))
#error TASK_SIZE_USER64 exceeds user VSID range
#endif
#endif
/*
* Define the address range of the kernel non-linear virtual area
*/
#ifdef CONFIG_PPC_BOOK3E
#define KERN_VIRT_START ASM_CONST(0x8000000000000000)
#else
#define KERN_VIRT_START ASM_CONST(0xD000000000000000)
#endif
#define KERN_VIRT_SIZE PGTABLE_RANGE
/*
* The vmalloc space starts at the beginning of that region, and
* occupies half of it on hash CPUs and a quarter of it on Book3E
* (we keep a quarter for the virtual memmap)
*/
#define VMALLOC_START KERN_VIRT_START
#ifdef CONFIG_PPC_BOOK3E
#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 2)
#else
#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1)
#endif
#define VMALLOC_END (VMALLOC_START + VMALLOC_SIZE)
/*
* The second half of the kernel virtual space is used for IO mappings,
* it's itself carved into the PIO region (ISA and PHB IO space) and
* the ioremap space
*
* ISA_IO_BASE = KERN_IO_START, 64K reserved area
* PHB_IO_BASE = ISA_IO_BASE + 64K to ISA_IO_BASE + 2G, PHB IO spaces
* IOREMAP_BASE = ISA_IO_BASE + 2G to VMALLOC_START + PGTABLE_RANGE
*/
#define KERN_IO_START (KERN_VIRT_START + (KERN_VIRT_SIZE >> 1))
#define FULL_IO_SIZE 0x80000000ul
#define ISA_IO_BASE (KERN_IO_START)
#define ISA_IO_END (KERN_IO_START + 0x10000ul)
#define PHB_IO_BASE (ISA_IO_END)
#define PHB_IO_END (KERN_IO_START + FULL_IO_SIZE)
#define IOREMAP_BASE (PHB_IO_END)
#define IOREMAP_END (KERN_VIRT_START + KERN_VIRT_SIZE)
/*
* Region IDs
*/
#define REGION_SHIFT 60UL
#define REGION_MASK (0xfUL << REGION_SHIFT)
#define REGION_ID(ea) (((unsigned long)(ea)) >> REGION_SHIFT)
#define VMALLOC_REGION_ID (REGION_ID(VMALLOC_START))
#define KERNEL_REGION_ID (REGION_ID(PAGE_OFFSET))
#define VMEMMAP_REGION_ID (0xfUL) /* Server only */
#define USER_REGION_ID (0UL)
/*
* Defines the address of the vmemap area, in its own region on
* hash table CPUs and after the vmalloc space on Book3E
*/
#ifdef CONFIG_PPC_BOOK3E
#define VMEMMAP_BASE VMALLOC_END
#define VMEMMAP_END KERN_IO_START
#else
#define VMEMMAP_BASE (VMEMMAP_REGION_ID << REGION_SHIFT)
#endif
#define vmemmap ((struct page *)VMEMMAP_BASE)
/*
* Include the PTE bits definitions
*/
#ifdef CONFIG_PPC_BOOK3S
#include <asm/pte-hash64.h>
#else
#include <asm/pte-book3e.h>
#endif
#include <asm/pte-common.h>
#ifdef CONFIG_PPC_MM_SLICES
#define HAVE_ARCH_UNMAPPED_AREA
#define HAVE_ARCH_UNMAPPED_AREA_TOPDOWN
#endif /* CONFIG_PPC_MM_SLICES */
#ifndef __ASSEMBLY__
#include <linux/stddef.h>
#include <asm/tlbflush.h>
/*
* This is the default implementation of various PTE accessors, it's
* used in all cases except Book3S with 64K pages where we have a
* concept of sub-pages
*/
#ifndef __real_pte
#ifdef STRICT_MM_TYPECHECKS
#define __real_pte(e,p) ((real_pte_t){(e)})
#define __rpte_to_pte(r) ((r).pte)
#else
#define __real_pte(e,p) (e)
#define __rpte_to_pte(r) (__pte(r))
#endif
#define __rpte_to_hidx(r,index) (pte_val(__rpte_to_pte(r)) >> 12)
#define pte_iterate_hashed_subpages(rpte, psize, va, index, shift) \
do { \
index = 0; \
shift = mmu_psize_defs[psize].shift; \
#define pte_iterate_hashed_end() } while(0)
#ifdef CONFIG_PPC_HAS_HASH_64K
#define pte_pagesize_index(mm, addr, pte) get_slice_psize(mm, addr)
#else
#define pte_pagesize_index(mm, addr, pte) MMU_PAGE_4K
#endif
#endif /* __real_pte */
/* pte_clear moved to later in this file */
#define PMD_BAD_BITS (PTE_TABLE_SIZE-1)
#define PUD_BAD_BITS (PMD_TABLE_SIZE-1)
#define pmd_set(pmdp, pmdval) (pmd_val(*(pmdp)) = (pmdval))
#define pmd_none(pmd) (!pmd_val(pmd))
#define pmd_bad(pmd) (!is_kernel_addr(pmd_val(pmd)) \
|| (pmd_val(pmd) & PMD_BAD_BITS))
#define pmd_present(pmd) (pmd_val(pmd) != 0)
#define pmd_clear(pmdp) (pmd_val(*(pmdp)) = 0)
#define pmd_page_vaddr(pmd) (pmd_val(pmd) & ~PMD_MASKED_BITS)
#define pmd_page(pmd) virt_to_page(pmd_page_vaddr(pmd))
#define pud_set(pudp, pudval) (pud_val(*(pudp)) = (pudval))
#define pud_none(pud) (!pud_val(pud))
#define pud_bad(pud) (!is_kernel_addr(pud_val(pud)) \
|| (pud_val(pud) & PUD_BAD_BITS))
#define pud_present(pud) (pud_val(pud) != 0)
#define pud_clear(pudp) (pud_val(*(pudp)) = 0)
#define pud_page_vaddr(pud) (pud_val(pud) & ~PUD_MASKED_BITS)
#define pud_page(pud) virt_to_page(pud_page_vaddr(pud))
#define pgd_set(pgdp, pudp) ({pgd_val(*(pgdp)) = (unsigned long)(pudp);})
/*
* Find an entry in a page-table-directory. We combine the address region
* (the high order N bits) and the pgd portion of the address.
*/
/* to avoid overflow in free_pgtables we don't use PTRS_PER_PGD here */
#define pgd_index(address) (((address) >> (PGDIR_SHIFT)) & 0x1ff)
#define pgd_offset(mm, address) ((mm)->pgd + pgd_index(address))
#define pmd_offset(pudp,addr) \
(((pmd_t *) pud_page_vaddr(*(pudp))) + (((addr) >> PMD_SHIFT) & (PTRS_PER_PMD - 1)))
#define pte_offset_kernel(dir,addr) \
(((pte_t *) pmd_page_vaddr(*(dir))) + (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)))
#define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr))
#define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr))
#define pte_unmap(pte) do { } while(0)
#define pte_unmap_nested(pte) do { } while(0)
/* to find an entry in a kernel page-table-directory */
/* This now only contains the vmalloc pages */
#define pgd_offset_k(address) pgd_offset(&init_mm, address)
/* Atomic PTE updates */
static inline unsigned long pte_update(struct mm_struct *mm,
unsigned long addr,
pte_t *ptep, unsigned long clr,
int huge)
{
#ifdef PTE_ATOMIC_UPDATES
unsigned long old, tmp;
__asm__ __volatile__(
"1: ldarx %0,0,%3 # pte_update\n\
andi. %1,%0,%6\n\
bne- 1b \n\
andc %1,%0,%4 \n\
stdcx. %1,0,%3 \n\
bne- 1b"
: "=&r" (old), "=&r" (tmp), "=m" (*ptep)
: "r" (ptep), "r" (clr), "m" (*ptep), "i" (_PAGE_BUSY)
: "cc" );
#else
unsigned long old = pte_val(*ptep);
*ptep = __pte(old & ~clr);
#endif
/* huge pages use the old page table lock */
if (!huge)
assert_pte_locked(mm, addr);
#ifdef CONFIG_PPC_STD_MMU_64
if (old & _PAGE_HASHPTE)
hpte_need_flush(mm, addr, ptep, old, huge);
#endif
return old;
}
static inline int __ptep_test_and_clear_young(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
unsigned long old;
if ((pte_val(*ptep) & (_PAGE_ACCESSED | _PAGE_HASHPTE)) == 0)
return 0;
old = pte_update(mm, addr, ptep, _PAGE_ACCESSED, 0);
return (old & _PAGE_ACCESSED) != 0;
}
#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
#define ptep_test_and_clear_young(__vma, __addr, __ptep) \
({ \
int __r; \
__r = __ptep_test_and_clear_young((__vma)->vm_mm, __addr, __ptep); \
__r; \
})
#define __HAVE_ARCH_PTEP_SET_WRPROTECT
static inline void ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
unsigned long old;
if ((pte_val(*ptep) & _PAGE_RW) == 0)
return;
old = pte_update(mm, addr, ptep, _PAGE_RW, 0);
}
static inline void huge_ptep_set_wrprotect(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
unsigned long old;
if ((pte_val(*ptep) & _PAGE_RW) == 0)
return;
old = pte_update(mm, addr, ptep, _PAGE_RW, 1);
}
/*
* We currently remove entries from the hashtable regardless of whether
* the entry was young or dirty. The generic routines only flush if the
* entry was young or dirty which is not good enough.
*
* We should be more intelligent about this but for the moment we override
* these functions and force a tlb flush unconditionally
*/
#define __HAVE_ARCH_PTEP_CLEAR_YOUNG_FLUSH
#define ptep_clear_flush_young(__vma, __address, __ptep) \
({ \
int __young = __ptep_test_and_clear_young((__vma)->vm_mm, __address, \
__ptep); \
__young; \
})
#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
unsigned long old = pte_update(mm, addr, ptep, ~0UL, 0);
return __pte(old);
}
static inline void pte_clear(struct mm_struct *mm, unsigned long addr,
pte_t * ptep)
{
pte_update(mm, addr, ptep, ~0UL, 0);
}
/* Set the dirty and/or accessed bits atomically in a linux PTE, this
* function doesn't need to flush the hash entry
*/
static inline void __ptep_set_access_flags(pte_t *ptep, pte_t entry)
{
unsigned long bits = pte_val(entry) &
(_PAGE_DIRTY | _PAGE_ACCESSED | _PAGE_RW | _PAGE_EXEC);
#ifdef PTE_ATOMIC_UPDATES
unsigned long old, tmp;
__asm__ __volatile__(
"1: ldarx %0,0,%4\n\
andi. %1,%0,%6\n\
bne- 1b \n\
or %0,%3,%0\n\
stdcx. %0,0,%4\n\
bne- 1b"
:"=&r" (old), "=&r" (tmp), "=m" (*ptep)
:"r" (bits), "r" (ptep), "m" (*ptep), "i" (_PAGE_BUSY)
:"cc");
#else
unsigned long old = pte_val(*ptep);
*ptep = __pte(old | bits);
#endif
}
#define __HAVE_ARCH_PTE_SAME
#define pte_same(A,B) (((pte_val(A) ^ pte_val(B)) & ~_PAGE_HPTEFLAGS) == 0)
#define pte_ERROR(e) \
printk("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, pte_val(e))
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %08lx.\n", __FILE__, __LINE__, pmd_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
/* Encode and de-code a swap entry */
#define __swp_type(entry) (((entry).val >> 1) & 0x3f)
#define __swp_offset(entry) ((entry).val >> 8)
#define __swp_entry(type, offset) ((swp_entry_t){((type)<< 1)|((offset)<<8)})
#define __pte_to_swp_entry(pte) ((swp_entry_t){pte_val(pte) >> PTE_RPN_SHIFT})
#define __swp_entry_to_pte(x) ((pte_t) { (x).val << PTE_RPN_SHIFT })
#define pte_to_pgoff(pte) (pte_val(pte) >> PTE_RPN_SHIFT)
#define pgoff_to_pte(off) ((pte_t) {((off) << PTE_RPN_SHIFT)|_PAGE_FILE})
#define PTE_FILE_MAX_BITS (BITS_PER_LONG - PTE_RPN_SHIFT)
void pgtable_cache_init(void);
/*
* find_linux_pte returns the address of a linux pte for a given
* effective address and directory. If not found, it returns zero.
*/static inline pte_t *find_linux_pte(pgd_t *pgdir, unsigned long ea)
{
pgd_t *pg;
pud_t *pu;
pmd_t *pm;
pte_t *pt = NULL;
pg = pgdir + pgd_index(ea);
if (!pgd_none(*pg)) {
pu = pud_offset(pg, ea);
if (!pud_none(*pu)) {
pm = pmd_offset(pu, ea);
if (pmd_present(*pm))
pt = pte_offset_kernel(pm, ea);
}
}
return pt;
}
pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long address);
#endif /* __ASSEMBLY__ */
#endif /* _ASM_POWERPC_PGTABLE_PPC64_H_ */
Reference in New Issue View Git Blame Copy Permalink