remarkable-linux/include/asm-um/pgtable-3level.h
Jeff Dike 8cd8fa557f uml: update address space affected by pud_clear
pud_clear wasn't setting the _PAGE_NEWPAGE bit, fooling tlb_flush into
thinking that this area of the address space was up-to-date and not unmapping
whatever was covered by the pud.

This manifested itself as ldconfig on x86_64 complaining about the first
library it looked at not being a valid ELF file.  A config file is mapped at
0x4000000, as the only thing mapped under its pud, and unmapped.  The
unmapping caused a pud_clear, which, due to this bug, didn't actually unmap
the config file data on the host.  The first library is then mapped at the
same location, but is not actually mapped on the host because accesses to it
cause no page faults.  As a result, ldconfig sees the old config file data.

[akpm@linux-foundation.org: coding-style cleanups]
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-11-14 18:45:37 -08:00

136 lines
3.4 KiB
C

/*
* Copyright 2003 PathScale Inc
* Derived from include/asm-i386/pgtable.h
* Licensed under the GPL
*/
#ifndef __UM_PGTABLE_3LEVEL_H
#define __UM_PGTABLE_3LEVEL_H
#include <asm-generic/pgtable-nopud.h>
/* PGDIR_SHIFT determines what a third-level page table entry can map */
#define PGDIR_SHIFT 30
#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
#define PGDIR_MASK (~(PGDIR_SIZE-1))
/* PMD_SHIFT determines the size of the area a second-level page table can
* map
*/
#define PMD_SHIFT 21
#define PMD_SIZE (1UL << PMD_SHIFT)
#define PMD_MASK (~(PMD_SIZE-1))
/*
* entries per page directory level
*/
#define PTRS_PER_PTE 512
#define PTRS_PER_PMD 512
#define USER_PTRS_PER_PGD ((TASK_SIZE + (PGDIR_SIZE - 1)) / PGDIR_SIZE)
#define PTRS_PER_PGD 512
#define FIRST_USER_ADDRESS 0
#define pte_ERROR(e) \
printk("%s:%d: bad pte %p(%016lx).\n", __FILE__, __LINE__, &(e), \
pte_val(e))
#define pmd_ERROR(e) \
printk("%s:%d: bad pmd %p(%016lx).\n", __FILE__, __LINE__, &(e), \
pmd_val(e))
#define pgd_ERROR(e) \
printk("%s:%d: bad pgd %p(%016lx).\n", __FILE__, __LINE__, &(e), \
pgd_val(e))
#define pud_none(x) (!(pud_val(x) & ~_PAGE_NEWPAGE))
#define pud_bad(x) ((pud_val(x) & (~PAGE_MASK & ~_PAGE_USER)) != _KERNPG_TABLE)
#define pud_present(x) (pud_val(x) & _PAGE_PRESENT)
#define pud_populate(mm, pud, pmd) \
set_pud(pud, __pud(_PAGE_TABLE + __pa(pmd)))
#define set_pud(pudptr, pudval) set_64bit((phys_t *) (pudptr), pud_val(pudval))
static inline int pgd_newpage(pgd_t pgd)
{
return(pgd_val(pgd) & _PAGE_NEWPAGE);
}
static inline void pgd_mkuptodate(pgd_t pgd) { pgd_val(pgd) &= ~_PAGE_NEWPAGE; }
#define set_pmd(pmdptr, pmdval) set_64bit((phys_t *) (pmdptr), pmd_val(pmdval))
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
{
pmd_t *pmd = (pmd_t *) __get_free_page(GFP_KERNEL);
if(pmd)
memset(pmd, 0, PAGE_SIZE);
return pmd;
}
static inline void pud_clear (pud_t *pud)
{
set_pud(pud, __pud(_PAGE_NEWPAGE));
}
#define pud_page(pud) phys_to_page(pud_val(pud) & PAGE_MASK)
#define pud_page_vaddr(pud) \
((struct page *) __va(pud_val(pud) & PAGE_MASK))
/* Find an entry in the second-level page table.. */
#define pmd_offset(pud, address) ((pmd_t *) pud_page_vaddr(*(pud)) + \
pmd_index(address))
static inline unsigned long pte_pfn(pte_t pte)
{
return phys_to_pfn(pte_val(pte));
}
static inline pte_t pfn_pte(pfn_t page_nr, pgprot_t pgprot)
{
pte_t pte;
phys_t phys = pfn_to_phys(page_nr);
pte_set_val(pte, phys, pgprot);
return pte;
}
static inline pmd_t pfn_pmd(pfn_t page_nr, pgprot_t pgprot)
{
return __pmd((page_nr << PAGE_SHIFT) | pgprot_val(pgprot));
}
/*
* Bits 0 through 3 are taken in the low part of the pte,
* put the 32 bits of offset into the high part.
*/
#define PTE_FILE_MAX_BITS 32
#ifdef CONFIG_64BIT
#define pte_to_pgoff(p) ((p).pte >> 32)
#define pgoff_to_pte(off) ((pte_t) { ((off) << 32) | _PAGE_FILE })
#else
#define pte_to_pgoff(pte) ((pte).pte_high)
#define pgoff_to_pte(off) ((pte_t) { _PAGE_FILE, (off) })
#endif
#endif
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/