153 lines
3.6 KiB
C
153 lines
3.6 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* file.c - NILFS regular file handling primitives including fsync().
|
|
*
|
|
* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
|
|
*
|
|
* Written by Amagai Yoshiji and Ryusuke Konishi.
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/writeback.h>
|
|
#include "nilfs.h"
|
|
#include "segment.h"
|
|
|
|
int nilfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
|
|
{
|
|
/*
|
|
* Called from fsync() system call
|
|
* This is the only entry point that can catch write and synch
|
|
* timing for both data blocks and intermediate blocks.
|
|
*
|
|
* This function should be implemented when the writeback function
|
|
* will be implemented.
|
|
*/
|
|
struct the_nilfs *nilfs;
|
|
struct inode *inode = file->f_mapping->host;
|
|
int err = 0;
|
|
|
|
if (nilfs_inode_dirty(inode)) {
|
|
if (datasync)
|
|
err = nilfs_construct_dsync_segment(inode->i_sb, inode,
|
|
start, end);
|
|
else
|
|
err = nilfs_construct_segment(inode->i_sb);
|
|
}
|
|
|
|
nilfs = inode->i_sb->s_fs_info;
|
|
if (!err)
|
|
err = nilfs_flush_device(nilfs);
|
|
|
|
return err;
|
|
}
|
|
|
|
static vm_fault_t nilfs_page_mkwrite(struct vm_fault *vmf)
|
|
{
|
|
struct vm_area_struct *vma = vmf->vma;
|
|
struct page *page = vmf->page;
|
|
struct inode *inode = file_inode(vma->vm_file);
|
|
struct nilfs_transaction_info ti;
|
|
int ret = 0;
|
|
|
|
if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))
|
|
return VM_FAULT_SIGBUS; /* -ENOSPC */
|
|
|
|
sb_start_pagefault(inode->i_sb);
|
|
lock_page(page);
|
|
if (page->mapping != inode->i_mapping ||
|
|
page_offset(page) >= i_size_read(inode) || !PageUptodate(page)) {
|
|
unlock_page(page);
|
|
ret = -EFAULT; /* make the VM retry the fault */
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* check to see if the page is mapped already (no holes)
|
|
*/
|
|
if (PageMappedToDisk(page))
|
|
goto mapped;
|
|
|
|
if (page_has_buffers(page)) {
|
|
struct buffer_head *bh, *head;
|
|
int fully_mapped = 1;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (!buffer_mapped(bh)) {
|
|
fully_mapped = 0;
|
|
break;
|
|
}
|
|
} while (bh = bh->b_this_page, bh != head);
|
|
|
|
if (fully_mapped) {
|
|
SetPageMappedToDisk(page);
|
|
goto mapped;
|
|
}
|
|
}
|
|
unlock_page(page);
|
|
|
|
/*
|
|
* fill hole blocks
|
|
*/
|
|
ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);
|
|
/* never returns -ENOMEM, but may return -ENOSPC */
|
|
if (unlikely(ret))
|
|
goto out;
|
|
|
|
file_update_time(vma->vm_file);
|
|
ret = block_page_mkwrite(vma, vmf, nilfs_get_block);
|
|
if (ret) {
|
|
nilfs_transaction_abort(inode->i_sb);
|
|
goto out;
|
|
}
|
|
nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));
|
|
nilfs_transaction_commit(inode->i_sb);
|
|
|
|
mapped:
|
|
wait_for_stable_page(page);
|
|
out:
|
|
sb_end_pagefault(inode->i_sb);
|
|
return block_page_mkwrite_return(ret);
|
|
}
|
|
|
|
static const struct vm_operations_struct nilfs_file_vm_ops = {
|
|
.fault = filemap_fault,
|
|
.map_pages = filemap_map_pages,
|
|
.page_mkwrite = nilfs_page_mkwrite,
|
|
};
|
|
|
|
static int nilfs_file_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
file_accessed(file);
|
|
vma->vm_ops = &nilfs_file_vm_ops;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* We have mostly NULL's here: the current defaults are ok for
|
|
* the nilfs filesystem.
|
|
*/
|
|
const struct file_operations nilfs_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read_iter = generic_file_read_iter,
|
|
.write_iter = generic_file_write_iter,
|
|
.unlocked_ioctl = nilfs_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = nilfs_compat_ioctl,
|
|
#endif /* CONFIG_COMPAT */
|
|
.mmap = nilfs_file_mmap,
|
|
.open = generic_file_open,
|
|
/* .release = nilfs_release_file, */
|
|
.fsync = nilfs_sync_file,
|
|
.splice_read = generic_file_splice_read,
|
|
};
|
|
|
|
const struct inode_operations nilfs_file_inode_operations = {
|
|
.setattr = nilfs_setattr,
|
|
.permission = nilfs_permission,
|
|
.fiemap = nilfs_fiemap,
|
|
};
|
|
|
|
/* end of file */
|