*
* started by Ingo Molnar, Copyright (C) 2002, 2003
*/
-
+#include <linux/backing-dev.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/file.h>
#include <linux/pagemap.h>
#include <linux/swapops.h>
#include <linux/rmap.h>
-#include <linux/module.h>
#include <linux/syscalls.h>
+#include <linux/mmu_notifier.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
+#include "internal.h"
+
static void zap_pte(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
if (page) {
if (pte_dirty(pte))
set_page_dirty(page);
- page_remove_rmap(page, vma);
+ page_remove_rmap(page);
page_cache_release(page);
update_hiwater_rss(mm);
- dec_mm_counter(mm, file_rss);
+ dec_mm_counter(mm, MM_FILEPAGES);
}
} else {
if (!pte_file(pte))
}
-/***
- * sys_remap_file_pages - remap arbitrary pages of a shared backing store
- * file within an existing vma.
+/**
+ * sys_remap_file_pages - remap arbitrary pages of an existing VM_SHARED vma
* @start: start of the remapped virtual memory range
* @size: size of the remapped virtual memory range
- * @prot: new protection bits of the range
- * @pgoff: to be mapped page of the backing store file
+ * @prot: new protection bits of the range (see NOTE)
+ * @pgoff: to-be-mapped page of the backing store file
* @flags: 0 or MAP_NONBLOCKED - the later will cause no IO.
*
- * this syscall works purely via pagetables, so it's the most efficient
+ * sys_remap_file_pages remaps arbitrary pages of an existing VM_SHARED vma
+ * (shared backing store file).
+ *
+ * This syscall works purely via pagetables, so it's the most efficient
* way to map the same (large) file into a given virtual window. Unlike
* mmap()/mremap() it does not create any new vmas. The new mappings are
* also safe across swapout.
*
- * NOTE: the 'prot' parameter right now is ignored, and the vma's default
- * protection is used. Arbitrary protections might be implemented in the
- * future.
+ * NOTE: the @prot parameter right now is ignored (but must be zero),
+ * and the vma's default protection is used. Arbitrary protections
+ * might be implemented in the future.
*/
-asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size,
- unsigned long __prot, unsigned long pgoff, unsigned long flags)
+SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
+ unsigned long, prot, unsigned long, pgoff, unsigned long, flags)
{
struct mm_struct *mm = current->mm;
struct address_space *mapping;
- unsigned long end = start + size;
struct vm_area_struct *vma;
int err = -EINVAL;
int has_write_lock = 0;
- if (__prot)
+ if (prot)
return err;
/*
* Sanitize the syscall parameters:
if (start + size <= start)
return err;
+ /* Does pgoff wrap? */
+ if (pgoff + (size >> PAGE_SHIFT) < pgoff)
+ return err;
+
/* Can we represent this offset inside this architecture's pte's? */
#if PTE_FILE_MAX_BITS < BITS_PER_LONG
if (pgoff + (size >> PAGE_SHIFT) >= (1UL << PTE_FILE_MAX_BITS))
if (vma->vm_private_data && !(vma->vm_flags & VM_NONLINEAR))
goto out;
- if (!vma->vm_flags & VM_CAN_NONLINEAR)
+ if (!(vma->vm_flags & VM_CAN_NONLINEAR))
goto out;
- if (end <= start || start < vma->vm_start || end > vma->vm_end)
+ if (start < vma->vm_start || start + size > vma->vm_end)
goto out;
/* Must set VM_NONLINEAR before any pages are populated. */
*/
if (mapping_cap_account_dirty(mapping)) {
unsigned long addr;
+ struct file *file = vma->vm_file;
flags &= MAP_NONBLOCK;
- addr = mmap_region(vma->vm_file, start, size,
- flags, vma->vm_flags, pgoff, 1);
+ get_file(file);
+ addr = mmap_region(file, start, size,
+ flags, vma->vm_flags, pgoff);
+ fput(file);
if (IS_ERR_VALUE(addr)) {
err = addr;
} else {
}
goto out;
}
- spin_lock(&mapping->i_mmap_lock);
+ mutex_lock(&mapping->i_mmap_mutex);
flush_dcache_mmap_lock(mapping);
vma->vm_flags |= VM_NONLINEAR;
vma_prio_tree_remove(vma, &mapping->i_mmap);
vma_nonlinear_insert(vma, &mapping->i_mmap_nonlinear);
flush_dcache_mmap_unlock(mapping);
- spin_unlock(&mapping->i_mmap_lock);
+ mutex_unlock(&mapping->i_mmap_mutex);
}
+ if (vma->vm_flags & VM_LOCKED) {
+ /*
+ * drop PG_Mlocked flag for over-mapped range
+ */
+ vm_flags_t saved_flags = vma->vm_flags;
+ munlock_vma_pages_range(vma, start, start + size);
+ vma->vm_flags = saved_flags;
+ }
+
+ mmu_notifier_invalidate_range_start(mm, start, start + size);
err = populate_range(mm, vma, start, size, pgoff);
+ mmu_notifier_invalidate_range_end(mm, start, start + size);
if (!err && !(flags & MAP_NONBLOCK)) {
- if (unlikely(has_write_lock)) {
- downgrade_write(&mm->mmap_sem);
- has_write_lock = 0;
+ if (vma->vm_flags & VM_LOCKED) {
+ /*
+ * might be mapping previously unmapped range of file
+ */
+ mlock_vma_pages_range(vma, start, start + size);
+ } else {
+ if (unlikely(has_write_lock)) {
+ downgrade_write(&mm->mmap_sem);
+ has_write_lock = 0;
+ }
+ make_pages_present(start, start+size);
}
- make_pages_present(start, start+size);
}
/*
return err;
}
-
projects / linux-flexiantxendom0-3.2.10.git / blobdiff