[mirror_ubuntu-artful-kernel.git] / fs / nilfs2 / file.c

/*
 * file.c - NILFS regular file handling primitives including fsync().
 *
 * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * Written by Amagai Yoshiji <amagai@osrg.net>,
 *            Ryusuke Konishi <ryusuke@osrg.net>
 */

#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;

	err = filemap_write_and_wait_range(inode->i_mapping, start, end);
	if (err)
		return err;
	mutex_lock(&inode->i_mutex);

	if (nilfs_inode_dirty(inode)) {
		if (datasync)
			err = nilfs_construct_dsync_segment(inode->i_sb, inode,
							    0, LLONG_MAX);
		else
			err = nilfs_construct_segment(inode->i_sb);
	}
	mutex_unlock(&inode->i_mutex);

	nilfs = inode->i_sb->s_fs_info;
	if (!err && nilfs_test_opt(nilfs, BARRIER)) {
		err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
		if (err != -EIO)
			err = 0;
	}
	return err;
}

static int nilfs_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct page *page = vmf->page;
	struct inode *inode = vma->vm_file->f_dentry->d_inode;
	struct nilfs_transaction_info ti;
	int ret;

	if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))
		return VM_FAULT_SIGBUS; /* -ENOSPC */

	lock_page(page);
	if (page->mapping != inode->i_mapping ||
	    page_offset(page) >= i_size_read(inode) || !PageUptodate(page)) {
		unlock_page(page);
		return VM_FAULT_NOPAGE; /* make the VM retry the fault */
	}

	/*
	 * 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))
		return VM_FAULT_SIGBUS;

	ret = block_page_mkwrite(vma, vmf, nilfs_get_block);
	if (ret != VM_FAULT_LOCKED) {
		nilfs_transaction_abort(inode->i_sb);
		return ret;
	}
	nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));
	nilfs_transaction_commit(inode->i_sb);

 mapped:
	wait_on_page_writeback(page);
	return VM_FAULT_LOCKED;
}

static const struct vm_operations_struct nilfs_file_vm_ops = {
	.fault		= filemap_fault,
	.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;
	vma->vm_flags |= VM_CAN_NONLINEAR;
	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		= do_sync_read,
	.write		= do_sync_write,
	.aio_read	= generic_file_aio_read,
	.aio_write	= generic_file_aio_write,
	.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 = {
	.truncate	= nilfs_truncate,
	.setattr	= nilfs_setattr,
	.permission     = nilfs_permission,
	.fiemap		= nilfs_fiemap,
};

/* end of file */
Commit	Line	Data
f183ff4f RK	1	/*
	2	* file.c - NILFS regular file handling primitives including fsync().
	3	*
	4	* Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*
	20	* Written by Amagai Yoshiji <amagai@osrg.net>,
	21	* Ryusuke Konishi <ryusuke@osrg.net>
	22	*/
	23
	24	#include <linux/fs.h>
	25	#include <linux/mm.h>
	26	#include <linux/writeback.h>
	27	#include "nilfs.h"
	28	#include "segment.h"
	29
02c24a82	30	int nilfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
f183ff4f RK	31	{
	32	/*
	33	* Called from fsync() system call
	34	* This is the only entry point that can catch write and synch
	35	* timing for both data blocks and intermediate blocks.
	36	*
	37	* This function should be implemented when the writeback function
	38	* will be implemented.
	39	*/
11475975	40	struct the_nilfs *nilfs;
7ea80859	41	struct inode *inode = file->f_mapping->host;
f183ff4f RK	42	int err;
f183ff4f RK	43
02c24a82 JB	44	err = filemap_write_and_wait_range(inode->i_mapping, start, end);
	45	if (err)
	46	return err;
	47	mutex_lock(&inode->i_mutex);
	48
11475975 RK	49	if (nilfs_inode_dirty(inode)) {
	50	if (datasync)
	51	err = nilfs_construct_dsync_segment(inode->i_sb, inode,
	52	0, LLONG_MAX);
	53	else
	54	err = nilfs_construct_segment(inode->i_sb);
02c24a82	55	}
02c24a82	56	mutex_unlock(&inode->i_mutex);
11475975 RK	57
	58	nilfs = inode->i_sb->s_fs_info;
	59	if (!err && nilfs_test_opt(nilfs, BARRIER)) {
	60	err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
	61	if (err != -EIO)
	62	err = 0;
	63	}
f183ff4f RK	64	return err;
	65	}
	66
9ff05123	67	static int nilfs_page_mkwrite(struct vm_area_struct vma, struct vm_fault vmf)
f183ff4f	68	{
9ff05123 RK	69	struct page *page = vmf->page;
	70	struct inode *inode = vma->vm_file->f_dentry->d_inode;
	71	struct nilfs_transaction_info ti;
	72	int ret;
	73
e3154e97	74	if (unlikely(nilfs_near_disk_full(inode->i_sb->s_fs_info)))
9ff05123 RK	75	return VM_FAULT_SIGBUS; /* -ENOSPC */
	76
	77	lock_page(page);
	78	if (page->mapping != inode->i_mapping \|\|
	79	page_offset(page) >= i_size_read(inode) \|\| !PageUptodate(page)) {
	80	unlock_page(page);
	81	return VM_FAULT_NOPAGE; /* make the VM retry the fault */
	82	}
	83
	84	/*
	85	* check to see if the page is mapped already (no holes)
	86	*/
34094537	87	if (PageMappedToDisk(page))
9ff05123	88	goto mapped;
34094537	89
9ff05123 RK	90	if (page_has_buffers(page)) {
	91	struct buffer_head bh, head;
	92	int fully_mapped = 1;
	93
	94	bh = head = page_buffers(page);
	95	do {
	96	if (!buffer_mapped(bh)) {
	97	fully_mapped = 0;
	98	break;
	99	}
	100	} while (bh = bh->b_this_page, bh != head);
	101
	102	if (fully_mapped) {
	103	SetPageMappedToDisk(page);
9ff05123 RK	104	goto mapped;
	105	}
	106	}
	107	unlock_page(page);
	108
	109	/*
	110	* fill hole blocks
	111	*/
	112	ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);
	113	/* never returns -ENOMEM, but may return -ENOSPC */
	114	if (unlikely(ret))
	115	return VM_FAULT_SIGBUS;
	116
	117	ret = block_page_mkwrite(vma, vmf, nilfs_get_block);
34094537	118	if (ret != VM_FAULT_LOCKED) {
9ff05123 RK	119	nilfs_transaction_abort(inode->i_sb);
	120	return ret;
	121	}
34094537	122	nilfs_set_file_dirty(inode, 1 << (PAGE_SHIFT - inode->i_blkbits));
9ff05123 RK	123	nilfs_transaction_commit(inode->i_sb);
	124
	125	mapped:
f183ff4f	126	wait_on_page_writeback(page);
34094537	127	return VM_FAULT_LOCKED;
f183ff4f RK	128	}
f183ff4f RK	129
f0f37e2f	130	static const struct vm_operations_struct nilfs_file_vm_ops = {
f183ff4f RK	131	.fault = filemap_fault,
	132	.page_mkwrite = nilfs_page_mkwrite,
	133	};
	134
	135	static int nilfs_file_mmap(struct file file, struct vm_area_struct vma)
	136	{
	137	file_accessed(file);
	138	vma->vm_ops = &nilfs_file_vm_ops;
	139	vma->vm_flags \|= VM_CAN_NONLINEAR;
	140	return 0;
	141	}
	142
	143	/*
	144	* We have mostly NULL's here: the current defaults are ok for
	145	* the nilfs filesystem.
	146	*/
828c0950	147	const struct file_operations nilfs_file_operations = {
f183ff4f RK	148	.llseek = generic_file_llseek,
	149	.read = do_sync_read,
	150	.write = do_sync_write,
	151	.aio_read = generic_file_aio_read,
f30bf3e4	152	.aio_write = generic_file_aio_write,
7a946193	153	.unlocked_ioctl = nilfs_ioctl,
f183ff4f	154	#ifdef CONFIG_COMPAT
828b1c50	155	.compat_ioctl = nilfs_compat_ioctl,
f183ff4f RK	156	#endif /* CONFIG_COMPAT */
	157	.mmap = nilfs_file_mmap,
	158	.open = generic_file_open,
	159	/* .release = nilfs_release_file, */
	160	.fsync = nilfs_sync_file,
	161	.splice_read = generic_file_splice_read,
	162	};
	163
6e1d5dcc	164	const struct inode_operations nilfs_file_inode_operations = {
f183ff4f RK	165	.truncate = nilfs_truncate,
	166	.setattr = nilfs_setattr,
	167	.permission = nilfs_permission,
622daaff	168	.fiemap = nilfs_fiemap,
f183ff4f RK	169	};
	170
	171	/* end of file */