fs/xfs/linux-2.6/xfs_file.c - kernel/prism - Git at Google

 /*
  * Copyright (c) 2000-2005 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
  * 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.
  *
  * This program is distributed in the hope that it would 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 the Free Software Foundation,
  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 #include "xfs.h"
 #include "xfs_bit.h"
 #include "xfs_log.h"
 #include "xfs_inum.h"
 #include "xfs_sb.h"
 #include "xfs_ag.h"
 #include "xfs_dir2.h"
 #include "xfs_trans.h"
 #include "xfs_dmapi.h"
 #include "xfs_mount.h"
 #include "xfs_bmap_btree.h"
 #include "xfs_alloc_btree.h"
 #include "xfs_ialloc_btree.h"
 #include "xfs_alloc.h"
 #include "xfs_btree.h"
 #include "xfs_attr_sf.h"
 #include "xfs_dir2_sf.h"
 #include "xfs_dinode.h"
 #include "xfs_inode.h"
 #include "xfs_error.h"
 #include "xfs_rw.h"
 #include "xfs_vnodeops.h"
 #include "xfs_da_btree.h"
 #include "xfs_ioctl.h"

 #include <linux/dcache.h>

 static const struct vm_operations_struct xfs_file_vm_ops;

 STATIC ssize_t
 xfs_file_aio_read(
 	struct kiocb		*iocb,
 	const struct iovec	*iov,
 	unsigned long		nr_segs,
 	loff_t			pos)
 {
 	struct file		*file = iocb->ki_filp;
 	int			ioflags = IO_ISAIO;

 	BUG_ON(iocb->ki_pos != pos);
 	if (unlikely(file->f_flags & O_DIRECT))
 		ioflags |= IO_ISDIRECT;
 	if (file->f_mode & FMODE_NOCMTIME)
 		ioflags |= IO_INVIS;
 	return xfs_read(XFS_I(file->f_path.dentry->d_inode), iocb, iov,
 				nr_segs, &iocb->ki_pos, ioflags);
 }

 STATIC ssize_t
 xfs_file_aio_write(
 	struct kiocb		*iocb,
 	const struct iovec	*iov,
 	unsigned long		nr_segs,
 	loff_t			pos)
 {
 	struct file		*file = iocb->ki_filp;
 	int			ioflags = IO_ISAIO;

 	BUG_ON(iocb->ki_pos != pos);
 	if (unlikely(file->f_flags & O_DIRECT))
 		ioflags |= IO_ISDIRECT;
 	if (file->f_mode & FMODE_NOCMTIME)
 		ioflags |= IO_INVIS;
 	return xfs_write(XFS_I(file->f_mapping->host), iocb, iov, nr_segs,
 				&iocb->ki_pos, ioflags);
 }

 STATIC ssize_t
 xfs_file_splice_read(
 	struct file		*infilp,
 	loff_t			*ppos,
 	struct pipe_inode_info	*pipe,
 	size_t			len,
 	unsigned int		flags)
 {
 	int			ioflags = 0;

 	if (infilp->f_mode & FMODE_NOCMTIME)
 		ioflags |= IO_INVIS;

 	return xfs_splice_read(XFS_I(infilp->f_path.dentry->d_inode),
 				   infilp, ppos, pipe, len, flags, ioflags);
 }

 STATIC ssize_t
 xfs_file_splice_write(
 	struct pipe_inode_info	*pipe,
 	struct file		*outfilp,
 	loff_t			*ppos,
 	size_t			len,
 	unsigned int		flags)
 {
 	int			ioflags = 0;

 	if (outfilp->f_mode & FMODE_NOCMTIME)
 		ioflags |= IO_INVIS;

 	return xfs_splice_write(XFS_I(outfilp->f_path.dentry->d_inode),
 				    pipe, outfilp, ppos, len, flags, ioflags);
 }

 STATIC int
 xfs_file_open(
 	struct inode	*inode,
 	struct file	*file)
 {
 	if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
 		return -EFBIG;
 	if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
 		return -EIO;
 	return 0;
 }

 STATIC int
 xfs_dir_open(
 	struct inode	*inode,
 	struct file	*file)
 {
 	struct xfs_inode *ip = XFS_I(inode);
 	int		mode;
 	int		error;

 	error = xfs_file_open(inode, file);
 	if (error)
 		return error;

 	/*
 	 * If there are any blocks, read-ahead block 0 as we're almost
 	 * certain to have the next operation be a read there.
 	 */
 	mode = xfs_ilock_map_shared(ip);
 	if (ip->i_d.di_nextents > 0)
 		xfs_da_reada_buf(NULL, ip, 0, XFS_DATA_FORK);
 	xfs_iunlock(ip, mode);
 	return 0;
 }

 STATIC int
 xfs_file_release(
 	struct inode	*inode,
 	struct file	*filp)
 {
 	return -xfs_release(XFS_I(inode));
 }

 /*
  * We ignore the datasync flag here because a datasync is effectively
  * identical to an fsync. That is, datasync implies that we need to write
  * only the metadata needed to be able to access the data that is written
  * if we crash after the call completes. Hence if we are writing beyond
  * EOF we have to log the inode size change as well, which makes it a
  * full fsync. If we don't write beyond EOF, the inode core will be
  * clean in memory and so we don't need to log the inode, just like
  * fsync.
  */
 STATIC int
 xfs_file_fsync(
 	struct file		*file,
 	struct dentry		*dentry,
 	int			datasync)
 {
 	struct xfs_inode	*ip = XFS_I(dentry->d_inode);

 	xfs_iflags_clear(ip, XFS_ITRUNCATED);
 	return -xfs_fsync(ip);
 }

 STATIC int
 xfs_file_readdir(
 	struct file	*filp,
 	void		*dirent,
 	filldir_t	filldir)
 {
 	struct inode	*inode = filp->f_path.dentry->d_inode;
 	xfs_inode_t	*ip = XFS_I(inode);
 	int		error;
 	size_t		bufsize;

 	/*
 	 * The Linux API doesn't pass down the total size of the buffer
 	 * we read into down to the filesystem.  With the filldir concept
 	 * it's not needed for correct information, but the XFS dir2 leaf
 	 * code wants an estimate of the buffer size to calculate it's
 	 * readahead window and size the buffers used for mapping to
 	 * physical blocks.
 	 *
 	 * Try to give it an estimate that's good enough, maybe at some
 	 * point we can change the ->readdir prototype to include the
 	 * buffer size.
 	 */
 	bufsize = (size_t)min_t(loff_t, PAGE_SIZE, ip->i_d.di_size);

 	error = xfs_readdir(ip, dirent, bufsize,
 				(xfs_off_t *)&filp->f_pos, filldir);
 	if (error)
 		return -error;
 	return 0;
 }

 STATIC int
 xfs_file_mmap(
 	struct file	*filp,
 	struct vm_area_struct *vma)
 {
 	vma->vm_ops = &xfs_file_vm_ops;
 	vma->vm_flags |= VM_CAN_NONLINEAR;

 	file_accessed(filp);
 	return 0;
 }

 /*
  * mmap()d file has taken write protection fault and is being made
  * writable. We can set the page state up correctly for a writable
  * page, which means we can do correct delalloc accounting (ENOSPC
  * checking!) and unwritten extent mapping.
  */
 STATIC int
 xfs_vm_page_mkwrite(
 	struct vm_area_struct	*vma,
 	struct vm_fault		*vmf)
 {
 	return block_page_mkwrite(vma, vmf, xfs_get_blocks);
 }

 const struct file_operations xfs_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
 	.write		= do_sync_write,
 	.aio_read	= xfs_file_aio_read,
 	.aio_write	= xfs_file_aio_write,
 	.splice_read	= xfs_file_splice_read,
 	.splice_write	= xfs_file_splice_write,
 	.unlocked_ioctl	= xfs_file_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl	= xfs_file_compat_ioctl,
 #endif
 	.mmap		= xfs_file_mmap,
 	.open		= xfs_file_open,
 	.release	= xfs_file_release,
 	.fsync		= xfs_file_fsync,
 #ifdef HAVE_FOP_OPEN_EXEC
 	.open_exec	= xfs_file_open_exec,
 #endif
 };

 const struct file_operations xfs_dir_file_operations = {
 	.open		= xfs_dir_open,
 	.read		= generic_read_dir,
 	.readdir	= xfs_file_readdir,
 	.llseek		= generic_file_llseek,
 	.unlocked_ioctl	= xfs_file_ioctl,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl	= xfs_file_compat_ioctl,
 #endif
 	.fsync		= xfs_file_fsync,
 };

 static const struct vm_operations_struct xfs_file_vm_ops = {
 	.fault		= filemap_fault,
 	.page_mkwrite	= xfs_vm_page_mkwrite,
 };
	/*
	* Copyright (c) 2000-2005 Silicon Graphics, Inc.
	* All Rights Reserved.
	*
	* 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.
	*
	* This program is distributed in the hope that it would 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 the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*/
	#include "xfs.h"
	#include "xfs_bit.h"
	#include "xfs_log.h"
	#include "xfs_inum.h"
	#include "xfs_sb.h"
	#include "xfs_ag.h"
	#include "xfs_dir2.h"
	#include "xfs_trans.h"
	#include "xfs_dmapi.h"
	#include "xfs_mount.h"
	#include "xfs_bmap_btree.h"
	#include "xfs_alloc_btree.h"
	#include "xfs_ialloc_btree.h"
	#include "xfs_alloc.h"
	#include "xfs_btree.h"
	#include "xfs_attr_sf.h"
	#include "xfs_dir2_sf.h"
	#include "xfs_dinode.h"
	#include "xfs_inode.h"
	#include "xfs_error.h"
	#include "xfs_rw.h"
	#include "xfs_vnodeops.h"
	#include "xfs_da_btree.h"
	#include "xfs_ioctl.h"

	#include <linux/dcache.h>

	static const struct vm_operations_struct xfs_file_vm_ops;

	STATIC ssize_t
	xfs_file_aio_read(
	struct kiocb *iocb,
	const struct iovec *iov,
	unsigned long nr_segs,
	loff_t pos)
	{
	struct file *file = iocb->ki_filp;
	int ioflags = IO_ISAIO;

	BUG_ON(iocb->ki_pos != pos);
	if (unlikely(file->f_flags & O_DIRECT))
	ioflags \|= IO_ISDIRECT;
	if (file->f_mode & FMODE_NOCMTIME)
	ioflags \|= IO_INVIS;
	return xfs_read(XFS_I(file->f_path.dentry->d_inode), iocb, iov,
	nr_segs, &iocb->ki_pos, ioflags);
	}

	STATIC ssize_t
	xfs_file_aio_write(
	struct kiocb *iocb,
	const struct iovec *iov,
	unsigned long nr_segs,
	loff_t pos)
	{
	struct file *file = iocb->ki_filp;
	int ioflags = IO_ISAIO;

	BUG_ON(iocb->ki_pos != pos);
	if (unlikely(file->f_flags & O_DIRECT))
	ioflags \|= IO_ISDIRECT;
	if (file->f_mode & FMODE_NOCMTIME)
	ioflags \|= IO_INVIS;
	return xfs_write(XFS_I(file->f_mapping->host), iocb, iov, nr_segs,
	&iocb->ki_pos, ioflags);
	}

	STATIC ssize_t
	xfs_file_splice_read(
	struct file *infilp,
	loff_t *ppos,
	struct pipe_inode_info *pipe,
	size_t len,
	unsigned int flags)
	{
	int ioflags = 0;

	if (infilp->f_mode & FMODE_NOCMTIME)
	ioflags \|= IO_INVIS;

	return xfs_splice_read(XFS_I(infilp->f_path.dentry->d_inode),
	infilp, ppos, pipe, len, flags, ioflags);
	}

	STATIC ssize_t
	xfs_file_splice_write(
	struct pipe_inode_info *pipe,
	struct file *outfilp,
	loff_t *ppos,
	size_t len,
	unsigned int flags)
	{
	int ioflags = 0;

	if (outfilp->f_mode & FMODE_NOCMTIME)
	ioflags \|= IO_INVIS;

	return xfs_splice_write(XFS_I(outfilp->f_path.dentry->d_inode),
	pipe, outfilp, ppos, len, flags, ioflags);
	}

	STATIC int
	xfs_file_open(
	struct inode *inode,
	struct file *file)
	{
	if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
	return -EFBIG;
	if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb)))
	return -EIO;
	return 0;
	}

	STATIC int
	xfs_dir_open(
	struct inode *inode,
	struct file *file)
	{
	struct xfs_inode *ip = XFS_I(inode);
	int mode;
	int error;

	error = xfs_file_open(inode, file);
	if (error)
	return error;

	/*
	* If there are any blocks, read-ahead block 0 as we're almost
	* certain to have the next operation be a read there.
	*/
	mode = xfs_ilock_map_shared(ip);
	if (ip->i_d.di_nextents > 0)
	xfs_da_reada_buf(NULL, ip, 0, XFS_DATA_FORK);
	xfs_iunlock(ip, mode);
	return 0;
	}

	STATIC int
	xfs_file_release(
	struct inode *inode,
	struct file *filp)
	{
	return -xfs_release(XFS_I(inode));
	}

	/*
	* We ignore the datasync flag here because a datasync is effectively
	* identical to an fsync. That is, datasync implies that we need to write
	* only the metadata needed to be able to access the data that is written
	* if we crash after the call completes. Hence if we are writing beyond
	* EOF we have to log the inode size change as well, which makes it a
	* full fsync. If we don't write beyond EOF, the inode core will be
	* clean in memory and so we don't need to log the inode, just like
	* fsync.
	*/
	STATIC int
	xfs_file_fsync(
	struct file *file,
	struct dentry *dentry,
	int datasync)
	{
	struct xfs_inode *ip = XFS_I(dentry->d_inode);

	xfs_iflags_clear(ip, XFS_ITRUNCATED);
	return -xfs_fsync(ip);
	}

	STATIC int
	xfs_file_readdir(
	struct file *filp,
	void *dirent,
	filldir_t filldir)
	{
	struct inode *inode = filp->f_path.dentry->d_inode;
	xfs_inode_t *ip = XFS_I(inode);
	int error;
	size_t bufsize;

	/*
	* The Linux API doesn't pass down the total size of the buffer
	* we read into down to the filesystem. With the filldir concept
	* it's not needed for correct information, but the XFS dir2 leaf
	* code wants an estimate of the buffer size to calculate it's
	* readahead window and size the buffers used for mapping to
	* physical blocks.
	*
	* Try to give it an estimate that's good enough, maybe at some
	* point we can change the ->readdir prototype to include the
	* buffer size.
	*/
	bufsize = (size_t)min_t(loff_t, PAGE_SIZE, ip->i_d.di_size);

	error = xfs_readdir(ip, dirent, bufsize,
	(xfs_off_t *)&filp->f_pos, filldir);
	if (error)
	return -error;
	return 0;
	}

	STATIC int
	xfs_file_mmap(
	struct file *filp,
	struct vm_area_struct *vma)
	{
	vma->vm_ops = &xfs_file_vm_ops;
	vma->vm_flags \|= VM_CAN_NONLINEAR;

	file_accessed(filp);
	return 0;
	}

	/*
	* mmap()d file has taken write protection fault and is being made
	* writable. We can set the page state up correctly for a writable
	* page, which means we can do correct delalloc accounting (ENOSPC
	* checking!) and unwritten extent mapping.
	*/
	STATIC int
	xfs_vm_page_mkwrite(
	struct vm_area_struct *vma,
	struct vm_fault *vmf)
	{
	return block_page_mkwrite(vma, vmf, xfs_get_blocks);
	}

	const struct file_operations xfs_file_operations = {
	.llseek = generic_file_llseek,
	.read = do_sync_read,
	.write = do_sync_write,
	.aio_read = xfs_file_aio_read,
	.aio_write = xfs_file_aio_write,
	.splice_read = xfs_file_splice_read,
	.splice_write = xfs_file_splice_write,
	.unlocked_ioctl = xfs_file_ioctl,
	#ifdef CONFIG_COMPAT
	.compat_ioctl = xfs_file_compat_ioctl,
	#endif
	.mmap = xfs_file_mmap,
	.open = xfs_file_open,
	.release = xfs_file_release,
	.fsync = xfs_file_fsync,
	#ifdef HAVE_FOP_OPEN_EXEC
	.open_exec = xfs_file_open_exec,
	#endif
	};

	const struct file_operations xfs_dir_file_operations = {
	.open = xfs_dir_open,
	.read = generic_read_dir,
	.readdir = xfs_file_readdir,
	.llseek = generic_file_llseek,
	.unlocked_ioctl = xfs_file_ioctl,
	#ifdef CONFIG_COMPAT
	.compat_ioctl = xfs_file_compat_ioctl,
	#endif
	.fsync = xfs_file_fsync,
	};

	static const struct vm_operations_struct xfs_file_vm_ops = {
	.fault = filemap_fault,
	.page_mkwrite = xfs_vm_page_mkwrite,
	};