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[PATCH] SH vdso: use install_special_mapping()

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Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Paul Mundt
2007-02-08 14:20:44 -08:00
committed by Linus Torvalds
parent c13e4ca247
commit 2affc857ef
1 changed files with 9 additions and 49 deletions
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58
arch/sh/kernel/vsyscall/vsyscall.c
View File

@@ -37,11 +37,12 @@ __setup("vdso=", vdso_setup);
* of the ELF DSO images included therein. * of the ELF DSO images included therein.
*/ */
extern const char vsyscall_trapa_start, vsyscall_trapa_end; extern const char vsyscall_trapa_start, vsyscall_trapa_end;
static void *syscall_page; static struct page *syscall_pages[1];
int __init vsyscall_init(void) int __init vsyscall_init(void)
{ {
syscall_page = (void *)get_zeroed_page(GFP_ATOMIC); void *syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
syscall_pages[0] = virt_to_page(syscall_page);
/* /*
* XXX: Map this page to a fixmap entry if we get around * XXX: Map this page to a fixmap entry if we get around
@@ -55,37 +56,10 @@ int __init vsyscall_init(void)
return 0; return 0;
} }
static struct page *syscall_vma_nopage(struct vm_area_struct *vma,
unsigned long address, int *type)
{
unsigned long offset = address - vma->vm_start;
struct page *page;
if (address < vma->vm_start || address > vma->vm_end)
return NOPAGE_SIGBUS;
page = virt_to_page(syscall_page + offset);
get_page(page);
return page;
}
/* Prevent VMA merging */
static void syscall_vma_close(struct vm_area_struct *vma)
{
}
static struct vm_operations_struct syscall_vm_ops = {
.nopage = syscall_vma_nopage,
.close = syscall_vma_close,
};
/* Setup a VMA at program startup for the vsyscall page */ /* Setup a VMA at program startup for the vsyscall page */
int arch_setup_additional_pages(struct linux_binprm *bprm, int arch_setup_additional_pages(struct linux_binprm *bprm,
int executable_stack) int executable_stack)
{ {
struct vm_area_struct *vma;
struct mm_struct *mm = current->mm; struct mm_struct *mm = current->mm;
unsigned long addr; unsigned long addr;
int ret; int ret;
@@ -97,30 +71,16 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
goto up_fail; goto up_fail;
} }
vma = kmem_cache_zalloc(vm_area_cachep, GFP_KERNEL); ret = install_special_mapping(mm, addr, PAGE_SIZE,
if (!vma) { VM_READ | VM_EXEC |
ret = -ENOMEM; VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC |
VM_ALWAYSDUMP,
syscall_pages);
if (unlikely(ret))
goto up_fail; goto up_fail;
}
vma->vm_start = addr;
vma->vm_end = addr + PAGE_SIZE;
/* MAYWRITE to allow gdb to COW and set breakpoints */
vma->vm_flags = VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC|VM_MAYWRITE;
vma->vm_flags |= mm->def_flags;
vma->vm_page_prot = protection_map[vma->vm_flags & 7];
vma->vm_ops = &syscall_vm_ops;
vma->vm_mm = mm;
ret = insert_vm_struct(mm, vma);
if (unlikely(ret)) {
kmem_cache_free(vm_area_cachep, vma);
goto up_fail;
}
current->mm->context.vdso = (void *)addr; current->mm->context.vdso = (void *)addr;
mm->total_vm++;
up_fail: up_fail:
up_write(&mm->mmap_sem); up_write(&mm->mmap_sem);
return ret; return ret;