[linux.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 <[email protected]>,
 *            Ryusuke Konishi <[email protected]>
 */

#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, struct dentry *dentry, 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 inode *inode = dentry->d_inode;
	int err;

	if (!nilfs_inode_dirty(inode))
		return 0;

	if (datasync)
		err = nilfs_construct_dsync_segment(inode->i_sb, inode, 0,
						    LLONG_MAX);
	else
		err = nilfs_construct_segment(inode->i_sb);

	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(NILFS_SB(inode->i_sb)->s_nilfs)))
		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)) {
		unlock_page(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);
			unlock_page(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 (unlikely(ret)) {
		nilfs_transaction_abort(inode->i_sb);
		return ret;
	}
	nilfs_transaction_commit(inode->i_sb);

 mapped:
	SetPageChecked(page);
	wait_on_page_writeback(page);
	return 0;
}

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.
 */
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_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,
};

struct inode_operations nilfs_file_inode_operations = {
	.truncate	= nilfs_truncate,
	.setattr	= nilfs_setattr,
	.permission     = nilfs_permission,
};

/* 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 <[email protected]>,
	21	* Ryusuke Konishi <[email protected]>
	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
	30	int nilfs_sync_file(struct file file, struct dentry dentry, int datasync)
	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	*/
	40	struct inode *inode = dentry->d_inode;
	41	int err;
	42
	43	if (!nilfs_inode_dirty(inode))
	44	return 0;
	45
	46	if (datasync)
f30bf3e4 RK	47	err = nilfs_construct_dsync_segment(inode->i_sb, inode, 0,
f30bf3e4 RK	48	LLONG_MAX);
f183ff4f RK	49	else
	50	err = nilfs_construct_segment(inode->i_sb);
	51
	52	return err;
	53	}
	54
9ff05123	55	static int nilfs_page_mkwrite(struct vm_area_struct vma, struct vm_fault vmf)
f183ff4f	56	{
9ff05123 RK	57	struct page *page = vmf->page;
	58	struct inode *inode = vma->vm_file->f_dentry->d_inode;
	59	struct nilfs_transaction_info ti;
	60	int ret;
	61
	62	if (unlikely(nilfs_near_disk_full(NILFS_SB(inode->i_sb)->s_nilfs)))
	63	return VM_FAULT_SIGBUS; /* -ENOSPC */
	64
	65	lock_page(page);
	66	if (page->mapping != inode->i_mapping \|\|
	67	page_offset(page) >= i_size_read(inode) \|\| !PageUptodate(page)) {
	68	unlock_page(page);
	69	return VM_FAULT_NOPAGE; /* make the VM retry the fault */
	70	}
	71
	72	/*
	73	* check to see if the page is mapped already (no holes)
	74	*/
	75	if (PageMappedToDisk(page)) {
	76	unlock_page(page);
	77	goto mapped;
	78	}
	79	if (page_has_buffers(page)) {
	80	struct buffer_head bh, head;
	81	int fully_mapped = 1;
	82
	83	bh = head = page_buffers(page);
	84	do {
	85	if (!buffer_mapped(bh)) {
	86	fully_mapped = 0;
	87	break;
	88	}
	89	} while (bh = bh->b_this_page, bh != head);
	90
	91	if (fully_mapped) {
	92	SetPageMappedToDisk(page);
	93	unlock_page(page);
	94	goto mapped;
	95	}
	96	}
	97	unlock_page(page);
	98
	99	/*
	100	* fill hole blocks
	101	*/
	102	ret = nilfs_transaction_begin(inode->i_sb, &ti, 1);
	103	/* never returns -ENOMEM, but may return -ENOSPC */
	104	if (unlikely(ret))
	105	return VM_FAULT_SIGBUS;
	106
	107	ret = block_page_mkwrite(vma, vmf, nilfs_get_block);
	108	if (unlikely(ret)) {
	109	nilfs_transaction_abort(inode->i_sb);
	110	return ret;
	111	}
	112	nilfs_transaction_commit(inode->i_sb);
	113
	114	mapped:
f183ff4f RK	115	SetPageChecked(page);
	116	wait_on_page_writeback(page);
	117	return 0;
	118	}
	119
	120	struct vm_operations_struct nilfs_file_vm_ops = {
	121	.fault = filemap_fault,
	122	.page_mkwrite = nilfs_page_mkwrite,
	123	};
	124
	125	static int nilfs_file_mmap(struct file file, struct vm_area_struct vma)
	126	{
	127	file_accessed(file);
	128	vma->vm_ops = &nilfs_file_vm_ops;
	129	vma->vm_flags \|= VM_CAN_NONLINEAR;
	130	return 0;
	131	}
	132
	133	/*
	134	* We have mostly NULL's here: the current defaults are ok for
	135	* the nilfs filesystem.
	136	*/
	137	struct file_operations nilfs_file_operations = {
	138	.llseek = generic_file_llseek,
	139	.read = do_sync_read,
	140	.write = do_sync_write,
	141	.aio_read = generic_file_aio_read,
f30bf3e4	142	.aio_write = generic_file_aio_write,
7a946193	143	.unlocked_ioctl = nilfs_ioctl,
f183ff4f	144	#ifdef CONFIG_COMPAT
8082d36a	145	.compat_ioctl = nilfs_ioctl,
f183ff4f RK	146	#endif /* CONFIG_COMPAT */
	147	.mmap = nilfs_file_mmap,
	148	.open = generic_file_open,
	149	/* .release = nilfs_release_file, */
	150	.fsync = nilfs_sync_file,
	151	.splice_read = generic_file_splice_read,
	152	};
	153
	154	struct inode_operations nilfs_file_inode_operations = {
	155	.truncate = nilfs_truncate,
	156	.setattr = nilfs_setattr,
	157	.permission = nilfs_permission,
	158	};
	159
	160	/* end of file */