![Russell King](/assets/img/avatar_default.png)
Add pud_offset() et.al. between the pgd and pmd code in preparation of using pgtable-nopud.h rather than 4level-fixup.h. This incorporates a fix from Jamie Iles <jamie@jamieiles.com> for uaccess_with_memcpy.c. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
484 lines
17 KiB
C
484 lines
17 KiB
C
/*
|
|
* arch/arm/include/asm/pgtable.h
|
|
*
|
|
* Copyright (C) 1995-2002 Russell King
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#ifndef _ASMARM_PGTABLE_H
|
|
#define _ASMARM_PGTABLE_H
|
|
|
|
#include <linux/const.h>
|
|
#include <asm-generic/4level-fixup.h>
|
|
#include <asm/proc-fns.h>
|
|
|
|
#ifndef CONFIG_MMU
|
|
|
|
#include "pgtable-nommu.h"
|
|
|
|
#else
|
|
|
|
#include <asm/memory.h>
|
|
#include <mach/vmalloc.h>
|
|
#include <asm/pgtable-hwdef.h>
|
|
|
|
/*
|
|
* Just any arbitrary offset to the start of the vmalloc VM area: the
|
|
* current 8MB value just means that there will be a 8MB "hole" after the
|
|
* physical memory until the kernel virtual memory starts. That means that
|
|
* any out-of-bounds memory accesses will hopefully be caught.
|
|
* The vmalloc() routines leaves a hole of 4kB between each vmalloced
|
|
* area for the same reason. ;)
|
|
*
|
|
* Note that platforms may override VMALLOC_START, but they must provide
|
|
* VMALLOC_END. VMALLOC_END defines the (exclusive) limit of this space,
|
|
* which may not overlap IO space.
|
|
*/
|
|
#ifndef VMALLOC_START
|
|
#define VMALLOC_OFFSET (8*1024*1024)
|
|
#define VMALLOC_START (((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
|
|
#endif
|
|
|
|
/*
|
|
* Hardware-wise, we have a two level page table structure, where the first
|
|
* level has 4096 entries, and the second level has 256 entries. Each entry
|
|
* is one 32-bit word. Most of the bits in the second level entry are used
|
|
* by hardware, and there aren't any "accessed" and "dirty" bits.
|
|
*
|
|
* Linux on the other hand has a three level page table structure, which can
|
|
* be wrapped to fit a two level page table structure easily - using the PGD
|
|
* and PTE only. However, Linux also expects one "PTE" table per page, and
|
|
* at least a "dirty" bit.
|
|
*
|
|
* Therefore, we tweak the implementation slightly - we tell Linux that we
|
|
* have 2048 entries in the first level, each of which is 8 bytes (iow, two
|
|
* hardware pointers to the second level.) The second level contains two
|
|
* hardware PTE tables arranged contiguously, preceded by Linux versions
|
|
* which contain the state information Linux needs. We, therefore, end up
|
|
* with 512 entries in the "PTE" level.
|
|
*
|
|
* This leads to the page tables having the following layout:
|
|
*
|
|
* pgd pte
|
|
* | |
|
|
* +--------+
|
|
* | | +------------+ +0
|
|
* +- - - - + | Linux pt 0 |
|
|
* | | +------------+ +1024
|
|
* +--------+ +0 | Linux pt 1 |
|
|
* | |-----> +------------+ +2048
|
|
* +- - - - + +4 | h/w pt 0 |
|
|
* | |-----> +------------+ +3072
|
|
* +--------+ +8 | h/w pt 1 |
|
|
* | | +------------+ +4096
|
|
*
|
|
* See L_PTE_xxx below for definitions of bits in the "Linux pt", and
|
|
* PTE_xxx for definitions of bits appearing in the "h/w pt".
|
|
*
|
|
* PMD_xxx definitions refer to bits in the first level page table.
|
|
*
|
|
* The "dirty" bit is emulated by only granting hardware write permission
|
|
* iff the page is marked "writable" and "dirty" in the Linux PTE. This
|
|
* means that a write to a clean page will cause a permission fault, and
|
|
* the Linux MM layer will mark the page dirty via handle_pte_fault().
|
|
* For the hardware to notice the permission change, the TLB entry must
|
|
* be flushed, and ptep_set_access_flags() does that for us.
|
|
*
|
|
* The "accessed" or "young" bit is emulated by a similar method; we only
|
|
* allow accesses to the page if the "young" bit is set. Accesses to the
|
|
* page will cause a fault, and handle_pte_fault() will set the young bit
|
|
* for us as long as the page is marked present in the corresponding Linux
|
|
* PTE entry. Again, ptep_set_access_flags() will ensure that the TLB is
|
|
* up to date.
|
|
*
|
|
* However, when the "young" bit is cleared, we deny access to the page
|
|
* by clearing the hardware PTE. Currently Linux does not flush the TLB
|
|
* for us in this case, which means the TLB will retain the transation
|
|
* until either the TLB entry is evicted under pressure, or a context
|
|
* switch which changes the user space mapping occurs.
|
|
*/
|
|
#define PTRS_PER_PTE 512
|
|
#define PTRS_PER_PMD 1
|
|
#define PTRS_PER_PGD 2048
|
|
|
|
#define PTE_HWTABLE_PTRS (PTRS_PER_PTE)
|
|
#define PTE_HWTABLE_OFF (PTE_HWTABLE_PTRS * sizeof(pte_t))
|
|
#define PTE_HWTABLE_SIZE (PTRS_PER_PTE * sizeof(u32))
|
|
|
|
/*
|
|
* PMD_SHIFT determines the size of the area a second-level page table can map
|
|
* PGDIR_SHIFT determines what a third-level page table entry can map
|
|
*/
|
|
#define PMD_SHIFT 21
|
|
#define PGDIR_SHIFT 21
|
|
|
|
#define LIBRARY_TEXT_START 0x0c000000
|
|
|
|
#ifndef __ASSEMBLY__
|
|
extern void __pte_error(const char *file, int line, pte_t);
|
|
extern void __pmd_error(const char *file, int line, pmd_t);
|
|
extern void __pgd_error(const char *file, int line, pgd_t);
|
|
|
|
#define pte_ERROR(pte) __pte_error(__FILE__, __LINE__, pte)
|
|
#define pmd_ERROR(pmd) __pmd_error(__FILE__, __LINE__, pmd)
|
|
#define pgd_ERROR(pgd) __pgd_error(__FILE__, __LINE__, pgd)
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
#define PMD_SIZE (1UL << PMD_SHIFT)
|
|
#define PMD_MASK (~(PMD_SIZE-1))
|
|
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
|
|
#define PGDIR_MASK (~(PGDIR_SIZE-1))
|
|
|
|
/*
|
|
* This is the lowest virtual address we can permit any user space
|
|
* mapping to be mapped at. This is particularly important for
|
|
* non-high vector CPUs.
|
|
*/
|
|
#define FIRST_USER_ADDRESS PAGE_SIZE
|
|
|
|
#define USER_PTRS_PER_PGD (TASK_SIZE / PGDIR_SIZE)
|
|
|
|
/*
|
|
* section address mask and size definitions.
|
|
*/
|
|
#define SECTION_SHIFT 20
|
|
#define SECTION_SIZE (1UL << SECTION_SHIFT)
|
|
#define SECTION_MASK (~(SECTION_SIZE-1))
|
|
|
|
/*
|
|
* ARMv6 supersection address mask and size definitions.
|
|
*/
|
|
#define SUPERSECTION_SHIFT 24
|
|
#define SUPERSECTION_SIZE (1UL << SUPERSECTION_SHIFT)
|
|
#define SUPERSECTION_MASK (~(SUPERSECTION_SIZE-1))
|
|
|
|
/*
|
|
* "Linux" PTE definitions.
|
|
*
|
|
* We keep two sets of PTEs - the hardware and the linux version.
|
|
* This allows greater flexibility in the way we map the Linux bits
|
|
* onto the hardware tables, and allows us to have YOUNG and DIRTY
|
|
* bits.
|
|
*
|
|
* The PTE table pointer refers to the hardware entries; the "Linux"
|
|
* entries are stored 1024 bytes below.
|
|
*/
|
|
#define L_PTE_PRESENT (_AT(pteval_t, 1) << 0)
|
|
#define L_PTE_YOUNG (_AT(pteval_t, 1) << 1)
|
|
#define L_PTE_FILE (_AT(pteval_t, 1) << 2) /* only when !PRESENT */
|
|
#define L_PTE_DIRTY (_AT(pteval_t, 1) << 6)
|
|
#define L_PTE_RDONLY (_AT(pteval_t, 1) << 7)
|
|
#define L_PTE_USER (_AT(pteval_t, 1) << 8)
|
|
#define L_PTE_XN (_AT(pteval_t, 1) << 9)
|
|
#define L_PTE_SHARED (_AT(pteval_t, 1) << 10) /* shared(v6), coherent(xsc3) */
|
|
|
|
/*
|
|
* These are the memory types, defined to be compatible with
|
|
* pre-ARMv6 CPUs cacheable and bufferable bits: XXCB
|
|
*/
|
|
#define L_PTE_MT_UNCACHED (_AT(pteval_t, 0x00) << 2) /* 0000 */
|
|
#define L_PTE_MT_BUFFERABLE (_AT(pteval_t, 0x01) << 2) /* 0001 */
|
|
#define L_PTE_MT_WRITETHROUGH (_AT(pteval_t, 0x02) << 2) /* 0010 */
|
|
#define L_PTE_MT_WRITEBACK (_AT(pteval_t, 0x03) << 2) /* 0011 */
|
|
#define L_PTE_MT_MINICACHE (_AT(pteval_t, 0x06) << 2) /* 0110 (sa1100, xscale) */
|
|
#define L_PTE_MT_WRITEALLOC (_AT(pteval_t, 0x07) << 2) /* 0111 */
|
|
#define L_PTE_MT_DEV_SHARED (_AT(pteval_t, 0x04) << 2) /* 0100 */
|
|
#define L_PTE_MT_DEV_NONSHARED (_AT(pteval_t, 0x0c) << 2) /* 1100 */
|
|
#define L_PTE_MT_DEV_WC (_AT(pteval_t, 0x09) << 2) /* 1001 */
|
|
#define L_PTE_MT_DEV_CACHED (_AT(pteval_t, 0x0b) << 2) /* 1011 */
|
|
#define L_PTE_MT_MASK (_AT(pteval_t, 0x0f) << 2)
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
/*
|
|
* The pgprot_* and protection_map entries will be fixed up in runtime
|
|
* to include the cachable and bufferable bits based on memory policy,
|
|
* as well as any architecture dependent bits like global/ASID and SMP
|
|
* shared mapping bits.
|
|
*/
|
|
#define _L_PTE_DEFAULT L_PTE_PRESENT | L_PTE_YOUNG
|
|
|
|
extern pgprot_t pgprot_user;
|
|
extern pgprot_t pgprot_kernel;
|
|
|
|
#define _MOD_PROT(p, b) __pgprot(pgprot_val(p) | (b))
|
|
|
|
#define PAGE_NONE _MOD_PROT(pgprot_user, L_PTE_XN | L_PTE_RDONLY)
|
|
#define PAGE_SHARED _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_XN)
|
|
#define PAGE_SHARED_EXEC _MOD_PROT(pgprot_user, L_PTE_USER)
|
|
#define PAGE_COPY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
|
|
#define PAGE_COPY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
|
|
#define PAGE_READONLY _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
|
|
#define PAGE_READONLY_EXEC _MOD_PROT(pgprot_user, L_PTE_USER | L_PTE_RDONLY)
|
|
#define PAGE_KERNEL _MOD_PROT(pgprot_kernel, L_PTE_XN)
|
|
#define PAGE_KERNEL_EXEC pgprot_kernel
|
|
|
|
#define __PAGE_NONE __pgprot(_L_PTE_DEFAULT | L_PTE_RDONLY | L_PTE_XN)
|
|
#define __PAGE_SHARED __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_XN)
|
|
#define __PAGE_SHARED_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER)
|
|
#define __PAGE_COPY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
|
|
#define __PAGE_COPY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
|
|
#define __PAGE_READONLY __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY | L_PTE_XN)
|
|
#define __PAGE_READONLY_EXEC __pgprot(_L_PTE_DEFAULT | L_PTE_USER | L_PTE_RDONLY)
|
|
|
|
#define __pgprot_modify(prot,mask,bits) \
|
|
__pgprot((pgprot_val(prot) & ~(mask)) | (bits))
|
|
|
|
#define pgprot_noncached(prot) \
|
|
__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED)
|
|
|
|
#define pgprot_writecombine(prot) \
|
|
__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE)
|
|
|
|
#ifdef CONFIG_ARM_DMA_MEM_BUFFERABLE
|
|
#define pgprot_dmacoherent(prot) \
|
|
__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE | L_PTE_XN)
|
|
#define __HAVE_PHYS_MEM_ACCESS_PROT
|
|
struct file;
|
|
extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
|
|
unsigned long size, pgprot_t vma_prot);
|
|
#else
|
|
#define pgprot_dmacoherent(prot) \
|
|
__pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED | L_PTE_XN)
|
|
#endif
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
|
|
/*
|
|
* The table below defines the page protection levels that we insert into our
|
|
* Linux page table version. These get translated into the best that the
|
|
* architecture can perform. Note that on most ARM hardware:
|
|
* 1) We cannot do execute protection
|
|
* 2) If we could do execute protection, then read is implied
|
|
* 3) write implies read permissions
|
|
*/
|
|
#define __P000 __PAGE_NONE
|
|
#define __P001 __PAGE_READONLY
|
|
#define __P010 __PAGE_COPY
|
|
#define __P011 __PAGE_COPY
|
|
#define __P100 __PAGE_READONLY_EXEC
|
|
#define __P101 __PAGE_READONLY_EXEC
|
|
#define __P110 __PAGE_COPY_EXEC
|
|
#define __P111 __PAGE_COPY_EXEC
|
|
|
|
#define __S000 __PAGE_NONE
|
|
#define __S001 __PAGE_READONLY
|
|
#define __S010 __PAGE_SHARED
|
|
#define __S011 __PAGE_SHARED
|
|
#define __S100 __PAGE_READONLY_EXEC
|
|
#define __S101 __PAGE_READONLY_EXEC
|
|
#define __S110 __PAGE_SHARED_EXEC
|
|
#define __S111 __PAGE_SHARED_EXEC
|
|
|
|
#ifndef __ASSEMBLY__
|
|
/*
|
|
* ZERO_PAGE is a global shared page that is always zero: used
|
|
* for zero-mapped memory areas etc..
|
|
*/
|
|
extern struct page *empty_zero_page;
|
|
#define ZERO_PAGE(vaddr) (empty_zero_page)
|
|
|
|
|
|
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
|
|
|
|
/* to find an entry in a page-table-directory */
|
|
#define pgd_index(addr) ((addr) >> PGDIR_SHIFT)
|
|
|
|
#define pgd_offset(mm, addr) ((mm)->pgd + pgd_index(addr))
|
|
|
|
/* to find an entry in a kernel page-table-directory */
|
|
#define pgd_offset_k(addr) pgd_offset(&init_mm, addr)
|
|
|
|
/*
|
|
* The "pgd_xxx()" functions here are trivial for a folded two-level
|
|
* setup: the pgd is never bad, and a pmd always exists (as it's folded
|
|
* into the pgd entry)
|
|
*/
|
|
#define pgd_none(pgd) (0)
|
|
#define pgd_bad(pgd) (0)
|
|
#define pgd_present(pgd) (1)
|
|
#define pgd_clear(pgdp) do { } while (0)
|
|
#define set_pgd(pgd,pgdp) do { } while (0)
|
|
#define set_pud(pud,pudp) do { } while (0)
|
|
|
|
|
|
/* Find an entry in the second-level page table.. */
|
|
#define pmd_offset(dir, addr) ((pmd_t *)(dir))
|
|
|
|
#define pmd_none(pmd) (!pmd_val(pmd))
|
|
#define pmd_present(pmd) (pmd_val(pmd))
|
|
#define pmd_bad(pmd) (pmd_val(pmd) & 2)
|
|
|
|
#define copy_pmd(pmdpd,pmdps) \
|
|
do { \
|
|
pmdpd[0] = pmdps[0]; \
|
|
pmdpd[1] = pmdps[1]; \
|
|
flush_pmd_entry(pmdpd); \
|
|
} while (0)
|
|
|
|
#define pmd_clear(pmdp) \
|
|
do { \
|
|
pmdp[0] = __pmd(0); \
|
|
pmdp[1] = __pmd(0); \
|
|
clean_pmd_entry(pmdp); \
|
|
} while (0)
|
|
|
|
static inline pte_t *pmd_page_vaddr(pmd_t pmd)
|
|
{
|
|
return __va(pmd_val(pmd) & PAGE_MASK);
|
|
}
|
|
|
|
#define pmd_page(pmd) pfn_to_page(__phys_to_pfn(pmd_val(pmd)))
|
|
|
|
/* we don't need complex calculations here as the pmd is folded into the pgd */
|
|
#define pmd_addr_end(addr,end) (end)
|
|
|
|
|
|
#ifndef CONFIG_HIGHPTE
|
|
#define __pte_map(pmd) pmd_page_vaddr(*(pmd))
|
|
#define __pte_unmap(pte) do { } while (0)
|
|
#else
|
|
#define __pte_map(pmd) (pte_t *)kmap_atomic(pmd_page(*(pmd)))
|
|
#define __pte_unmap(pte) kunmap_atomic(pte)
|
|
#endif
|
|
|
|
#define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
|
|
|
|
#define pte_offset_kernel(pmd,addr) (pmd_page_vaddr(*(pmd)) + pte_index(addr))
|
|
|
|
#define pte_offset_map(pmd,addr) (__pte_map(pmd) + pte_index(addr))
|
|
#define pte_unmap(pte) __pte_unmap(pte)
|
|
|
|
#define pte_pfn(pte) (pte_val(pte) >> PAGE_SHIFT)
|
|
#define pfn_pte(pfn,prot) __pte(__pfn_to_phys(pfn) | pgprot_val(prot))
|
|
|
|
#define pte_page(pte) pfn_to_page(pte_pfn(pte))
|
|
#define mk_pte(page,prot) pfn_pte(page_to_pfn(page), prot)
|
|
|
|
#define set_pte_ext(ptep,pte,ext) cpu_set_pte_ext(ptep,pte,ext)
|
|
#define pte_clear(mm,addr,ptep) set_pte_ext(ptep, __pte(0), 0)
|
|
|
|
#if __LINUX_ARM_ARCH__ < 6
|
|
static inline void __sync_icache_dcache(pte_t pteval)
|
|
{
|
|
}
|
|
#else
|
|
extern void __sync_icache_dcache(pte_t pteval);
|
|
#endif
|
|
|
|
static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
|
|
pte_t *ptep, pte_t pteval)
|
|
{
|
|
if (addr >= TASK_SIZE)
|
|
set_pte_ext(ptep, pteval, 0);
|
|
else {
|
|
__sync_icache_dcache(pteval);
|
|
set_pte_ext(ptep, pteval, PTE_EXT_NG);
|
|
}
|
|
}
|
|
|
|
#define pte_none(pte) (!pte_val(pte))
|
|
#define pte_present(pte) (pte_val(pte) & L_PTE_PRESENT)
|
|
#define pte_write(pte) (!(pte_val(pte) & L_PTE_RDONLY))
|
|
#define pte_dirty(pte) (pte_val(pte) & L_PTE_DIRTY)
|
|
#define pte_young(pte) (pte_val(pte) & L_PTE_YOUNG)
|
|
#define pte_exec(pte) (!(pte_val(pte) & L_PTE_XN))
|
|
#define pte_special(pte) (0)
|
|
|
|
#define pte_present_user(pte) \
|
|
((pte_val(pte) & (L_PTE_PRESENT | L_PTE_USER)) == \
|
|
(L_PTE_PRESENT | L_PTE_USER))
|
|
|
|
#define PTE_BIT_FUNC(fn,op) \
|
|
static inline pte_t pte_##fn(pte_t pte) { pte_val(pte) op; return pte; }
|
|
|
|
PTE_BIT_FUNC(wrprotect, |= L_PTE_RDONLY);
|
|
PTE_BIT_FUNC(mkwrite, &= ~L_PTE_RDONLY);
|
|
PTE_BIT_FUNC(mkclean, &= ~L_PTE_DIRTY);
|
|
PTE_BIT_FUNC(mkdirty, |= L_PTE_DIRTY);
|
|
PTE_BIT_FUNC(mkold, &= ~L_PTE_YOUNG);
|
|
PTE_BIT_FUNC(mkyoung, |= L_PTE_YOUNG);
|
|
|
|
static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
|
|
|
|
static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
|
|
{
|
|
const pteval_t mask = L_PTE_XN | L_PTE_RDONLY | L_PTE_USER;
|
|
pte_val(pte) = (pte_val(pte) & ~mask) | (pgprot_val(newprot) & mask);
|
|
return pte;
|
|
}
|
|
|
|
/*
|
|
* Encode and decode a swap entry. Swap entries are stored in the Linux
|
|
* page tables as follows:
|
|
*
|
|
* 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
|
|
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
* <--------------- offset --------------------> <- type --> 0 0 0
|
|
*
|
|
* This gives us up to 63 swap files and 32GB per swap file. Note that
|
|
* the offset field is always non-zero.
|
|
*/
|
|
#define __SWP_TYPE_SHIFT 3
|
|
#define __SWP_TYPE_BITS 6
|
|
#define __SWP_TYPE_MASK ((1 << __SWP_TYPE_BITS) - 1)
|
|
#define __SWP_OFFSET_SHIFT (__SWP_TYPE_BITS + __SWP_TYPE_SHIFT)
|
|
|
|
#define __swp_type(x) (((x).val >> __SWP_TYPE_SHIFT) & __SWP_TYPE_MASK)
|
|
#define __swp_offset(x) ((x).val >> __SWP_OFFSET_SHIFT)
|
|
#define __swp_entry(type,offset) ((swp_entry_t) { ((type) << __SWP_TYPE_SHIFT) | ((offset) << __SWP_OFFSET_SHIFT) })
|
|
|
|
#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
|
|
#define __swp_entry_to_pte(swp) ((pte_t) { (swp).val })
|
|
|
|
/*
|
|
* It is an error for the kernel to have more swap files than we can
|
|
* encode in the PTEs. This ensures that we know when MAX_SWAPFILES
|
|
* is increased beyond what we presently support.
|
|
*/
|
|
#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > __SWP_TYPE_BITS)
|
|
|
|
/*
|
|
* Encode and decode a file entry. File entries are stored in the Linux
|
|
* page tables as follows:
|
|
*
|
|
* 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1
|
|
* 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
|
|
* <----------------------- offset ------------------------> 1 0 0
|
|
*/
|
|
#define pte_file(pte) (pte_val(pte) & L_PTE_FILE)
|
|
#define pte_to_pgoff(x) (pte_val(x) >> 3)
|
|
#define pgoff_to_pte(x) __pte(((x) << 3) | L_PTE_FILE)
|
|
|
|
#define PTE_FILE_MAX_BITS 29
|
|
|
|
/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
|
|
/* FIXME: this is not correct */
|
|
#define kern_addr_valid(addr) (1)
|
|
|
|
#include <asm-generic/pgtable.h>
|
|
|
|
/*
|
|
* We provide our own arch_get_unmapped_area to cope with VIPT caches.
|
|
*/
|
|
#define HAVE_ARCH_UNMAPPED_AREA
|
|
|
|
/*
|
|
* remap a physical page `pfn' of size `size' with page protection `prot'
|
|
* into virtual address `from'
|
|
*/
|
|
#define io_remap_pfn_range(vma,from,pfn,size,prot) \
|
|
remap_pfn_range(vma, from, pfn, size, prot)
|
|
|
|
#define pgtable_cache_init() do { } while (0)
|
|
|
|
void identity_mapping_add(pgd_t *, unsigned long, unsigned long);
|
|
void identity_mapping_del(pgd_t *, unsigned long, unsigned long);
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
#endif /* CONFIG_MMU */
|
|
|
|
#endif /* _ASMARM_PGTABLE_H */
|