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Commit f98dc48f authored by Linus Torvalds's avatar Linus Torvalds
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Split out "msync" logic into a file of its own. No actual code 

changes.
parent a75568c6
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Showing with 218 additions and 203 deletions
mm/Makefile
View file @ f98dc48f
......@@ -14,6 +14,6 @@ export-objs := shmem.o filemap.o mempool.o page_alloc.o
obj-y := memory.o mmap.o filemap.o mprotect.o mlock.o mremap.o \
vmalloc.o slab.o bootmem.o swap.o vmscan.o page_io.o \
page_alloc.o swap_state.o swapfile.o numa.o oom_kill.o \
shmem.o highmem.o mempool.o
shmem.o highmem.o mempool.o msync.o
include $(TOPDIR)/Rules.make
mm/filemap.c
View file @ f98dc48f
......@@ -2082,107 +2082,6 @@ struct page * filemap_nopage(struct vm_area_struct * area, unsigned long address
return NULL;
}
/* Called with mm->page_table_lock held to protect against other
* threads/the swapper from ripping pte's out from under us.
*/
static inline int filemap_sync_pte(pte_t *ptep, pmd_t *pmdp, struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
{
pte_t pte = *ptep;
if (pte_present(pte)) {
struct page *page = pte_page(pte);
if (VALID_PAGE(page) && !PageReserved(page) && ptep_test_and_clear_dirty(ptep)) {
flush_tlb_page(vma, address);
set_page_dirty(page);
}
}
return 0;
}
static inline int filemap_sync_pte_range(pmd_t * pmd,
unsigned long address, unsigned long end,
struct vm_area_struct *vma, unsigned int flags)
{
pte_t *pte;
int error;
if (pmd_none(*pmd))
return 0;
if (pmd_bad(*pmd)) {
pmd_ERROR(*pmd);
pmd_clear(pmd);
return 0;
}
pte = pte_offset_map(pmd, address);
if ((address & PMD_MASK) != (end & PMD_MASK))
end = (address & PMD_MASK) + PMD_SIZE;
error = 0;
do {
error |= filemap_sync_pte(pte, pmd, vma, address, flags);
address += PAGE_SIZE;
pte++;
} while (address && (address < end));
pte_unmap(pte - 1);
return error;
}
static inline int filemap_sync_pmd_range(pgd_t * pgd,
unsigned long address, unsigned long end,
struct vm_area_struct *vma, unsigned int flags)
{
pmd_t * pmd;
int error;
if (pgd_none(*pgd))
return 0;
if (pgd_bad(*pgd)) {
pgd_ERROR(*pgd);
pgd_clear(pgd);
return 0;
}
pmd = pmd_offset(pgd, address);
if ((address & PGDIR_MASK) != (end & PGDIR_MASK))
end = (address & PGDIR_MASK) + PGDIR_SIZE;
error = 0;
do {
error |= filemap_sync_pte_range(pmd, address, end, vma, flags);
address = (address + PMD_SIZE) & PMD_MASK;
pmd++;
} while (address && (address < end));
return error;
}
int filemap_sync(struct vm_area_struct * vma, unsigned long address,
size_t size, unsigned int flags)
{
pgd_t * dir;
unsigned long end = address + size;
int error = 0;
/* Aquire the lock early; it may be possible to avoid dropping
* and reaquiring it repeatedly.
*/
spin_lock(&vma->vm_mm->page_table_lock);
dir = pgd_offset(vma->vm_mm, address);
flush_cache_range(vma, address, end);
if (address >= end)
BUG();
do {
error |= filemap_sync_pmd_range(dir, address, end, vma, flags);
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
flush_tlb_range(vma, end - size, end);
spin_unlock(&vma->vm_mm->page_table_lock);
return error;
}
static struct vm_operations_struct generic_file_vm_ops = {
nopage: filemap_nopage,
};
......@@ -2205,107 +2104,6 @@ int generic_file_mmap(struct file * file, struct vm_area_struct * vma)
return 0;
}
/*
* The msync() system call.
*/
/*
* MS_SYNC syncs the entire file - including mappings.
*
* MS_ASYNC initiates writeout of just the dirty mapped data.
* This provides no guarantee of file integrity - things like indirect
* blocks may not have started writeout. MS_ASYNC is primarily useful
* where the application knows that it has finished with the data and
* wishes to intelligently schedule its own I/O traffic.
*/
static int msync_interval(struct vm_area_struct * vma,
unsigned long start, unsigned long end, int flags)
{
int ret = 0;
struct file * file = vma->vm_file;
if (file && (vma->vm_flags & VM_SHARED)) {
ret = filemap_sync(vma, start, end-start, flags);
if (!ret && (flags & (MS_SYNC|MS_ASYNC))) {
struct inode * inode = file->f_dentry->d_inode;
down(&inode->i_sem);
ret = filemap_fdatasync(inode->i_mapping);
if (flags & MS_SYNC) {
int err;
if (file->f_op && file->f_op->fsync) {
err = file->f_op->fsync(file, file->f_dentry, 1);
if (err && !ret)
ret = err;
}
err = filemap_fdatawait(inode->i_mapping);
if (err && !ret)
ret = err;
}
up(&inode->i_sem);
}
}
return ret;
}
asmlinkage long sys_msync(unsigned long start, size_t len, int flags)
{
unsigned long end;
struct vm_area_struct * vma;
int unmapped_error, error = -EINVAL;
down_read(&current->mm->mmap_sem);
if (start & ~PAGE_MASK)
goto out;
len = (len + ~PAGE_MASK) & PAGE_MASK;
end = start + len;
if (end < start)
goto out;
if (flags & ~(MS_ASYNC | MS_INVALIDATE | MS_SYNC))
goto out;
error = 0;
if (end == start)
goto out;
/*
* If the interval [start,end) covers some unmapped address ranges,
* just ignore them, but return -EFAULT at the end.
*/
vma = find_vma(current->mm, start);
unmapped_error = 0;
for (;;) {
/* Still start < end. */
error = -EFAULT;
if (!vma)
goto out;
/* Here start < vma->vm_end. */
if (start < vma->vm_start) {
unmapped_error = -EFAULT;
start = vma->vm_start;
}
/* Here vma->vm_start <= start < vma->vm_end. */
if (end <= vma->vm_end) {
if (start < end) {
error = msync_interval(vma, start, end, flags);
if (error)
goto out;
}
error = unmapped_error;
goto out;
}
/* Here vma->vm_start <= start < vma->vm_end < end. */
error = msync_interval(vma, start, vma->vm_end, flags);
if (error)
goto out;
start = vma->vm_end;
vma = vma->vm_next;
}
out:
up_read(&current->mm->mmap_sem);
return error;
}
static inline void setup_read_behavior(struct vm_area_struct * vma,
int behavior)
{
......
mm/msync.c 0 → 100644
View file @ f98dc48f
/*
* linux/mm/msync.c
*
* Copyright (C) 1994-1999 Linus Torvalds
*/
/*
* The msync() system call.
*/
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
/*
* Called with mm->page_table_lock held to protect against other
* threads/the swapper from ripping pte's out from under us.
*/
static inline int filemap_sync_pte(pte_t *ptep, pmd_t *pmdp, struct vm_area_struct *vma,
unsigned long address, unsigned int flags)
{
pte_t pte = *ptep;
if (pte_present(pte)) {
struct page *page = pte_page(pte);
if (VALID_PAGE(page) && !PageReserved(page) && ptep_test_and_clear_dirty(ptep)) {
flush_tlb_page(vma, address);
set_page_dirty(page);
}
}
return 0;
}
static inline int filemap_sync_pte_range(pmd_t * pmd,
unsigned long address, unsigned long end,
struct vm_area_struct *vma, unsigned int flags)
{
pte_t *pte;
int error;
if (pmd_none(*pmd))
return 0;
if (pmd_bad(*pmd)) {
pmd_ERROR(*pmd);
pmd_clear(pmd);
return 0;
}
pte = pte_offset_map(pmd, address);
if ((address & PMD_MASK) != (end & PMD_MASK))
end = (address & PMD_MASK) + PMD_SIZE;
error = 0;
do {
error |= filemap_sync_pte(pte, pmd, vma, address, flags);
address += PAGE_SIZE;
pte++;
} while (address && (address < end));
pte_unmap(pte - 1);
return error;
}
static inline int filemap_sync_pmd_range(pgd_t * pgd,
unsigned long address, unsigned long end,
struct vm_area_struct *vma, unsigned int flags)
{
pmd_t * pmd;
int error;
if (pgd_none(*pgd))
return 0;
if (pgd_bad(*pgd)) {
pgd_ERROR(*pgd);
pgd_clear(pgd);
return 0;
}
pmd = pmd_offset(pgd, address);
if ((address & PGDIR_MASK) != (end & PGDIR_MASK))
end = (address & PGDIR_MASK) + PGDIR_SIZE;
error = 0;
do {
error |= filemap_sync_pte_range(pmd, address, end, vma, flags);
address = (address + PMD_SIZE) & PMD_MASK;
pmd++;
} while (address && (address < end));
return error;
}
int filemap_sync(struct vm_area_struct * vma, unsigned long address,
size_t size, unsigned int flags)
{
pgd_t * dir;
unsigned long end = address + size;
int error = 0;
/* Aquire the lock early; it may be possible to avoid dropping
* and reaquiring it repeatedly.
*/
spin_lock(&vma->vm_mm->page_table_lock);
dir = pgd_offset(vma->vm_mm, address);
flush_cache_range(vma, address, end);
if (address >= end)
BUG();
do {
error |= filemap_sync_pmd_range(dir, address, end, vma, flags);
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
} while (address && (address < end));
flush_tlb_range(vma, end - size, end);
spin_unlock(&vma->vm_mm->page_table_lock);
return error;
}
/*
* MS_SYNC syncs the entire file - including mappings.
*
* MS_ASYNC initiates writeout of just the dirty mapped data.
* This provides no guarantee of file integrity - things like indirect
* blocks may not have started writeout. MS_ASYNC is primarily useful
* where the application knows that it has finished with the data and
* wishes to intelligently schedule its own I/O traffic.
*/
static int msync_interval(struct vm_area_struct * vma,
unsigned long start, unsigned long end, int flags)
{
int ret = 0;
struct file * file = vma->vm_file;
if (file && (vma->vm_flags & VM_SHARED)) {
ret = filemap_sync(vma, start, end-start, flags);
if (!ret && (flags & (MS_SYNC|MS_ASYNC))) {
struct inode * inode = file->f_dentry->d_inode;
down(&inode->i_sem);
ret = filemap_fdatasync(inode->i_mapping);
if (flags & MS_SYNC) {
int err;
if (file->f_op && file->f_op->fsync) {
err = file->f_op->fsync(file, file->f_dentry, 1);
if (err && !ret)
ret = err;
}
err = filemap_fdatawait(inode->i_mapping);
if (err && !ret)
ret = err;
}
up(&inode->i_sem);
}
}
return ret;
}
asmlinkage long sys_msync(unsigned long start, size_t len, int flags)
{
unsigned long end;
struct vm_area_struct * vma;
int unmapped_error, error = -EINVAL;
down_read(&current->mm->mmap_sem);
if (start & ~PAGE_MASK)
goto out;
len = (len + ~PAGE_MASK) & PAGE_MASK;
end = start + len;
if (end < start)
goto out;
if (flags & ~(MS_ASYNC | MS_INVALIDATE | MS_SYNC))
goto out;
error = 0;
if (end == start)
goto out;
/*
* If the interval [start,end) covers some unmapped address ranges,
* just ignore them, but return -EFAULT at the end.
*/
vma = find_vma(current->mm, start);
unmapped_error = 0;
for (;;) {
/* Still start < end. */
error = -EFAULT;
if (!vma)
goto out;
/* Here start < vma->vm_end. */
if (start < vma->vm_start) {
unmapped_error = -EFAULT;
start = vma->vm_start;
}
/* Here vma->vm_start <= start < vma->vm_end. */
if (end <= vma->vm_end) {
if (start < end) {
error = msync_interval(vma, start, end, flags);
if (error)
goto out;
}
error = unmapped_error;
goto out;
}
/* Here vma->vm_start <= start < vma->vm_end < end. */
error = msync_interval(vma, start, vma->vm_end, flags);
if (error)
goto out;
start = vma->vm_end;
vma = vma->vm_next;
}
out:
up_read(&current->mm->mmap_sem);
return error;
}
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