OpenCloudOS-Kernel/fs/ext3/file.c

136 lines
3.5 KiB
C

/*
* linux/fs/ext3/file.c
*
* Copyright (C) 1992, 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* from
*
* linux/fs/minix/file.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* ext3 fs regular file handling primitives
*
* 64-bit file support on 64-bit platforms by Jakub Jelinek
* (jj@sunsite.ms.mff.cuni.cz)
*/
#include <linux/time.h>
#include <linux/fs.h>
#include <linux/jbd.h>
#include <linux/ext3_fs.h>
#include <linux/ext3_jbd.h>
#include "xattr.h"
#include "acl.h"
/*
* Called when an inode is released. Note that this is different
* from ext3_file_open: open gets called at every open, but release
* gets called only when /all/ the files are closed.
*/
static int ext3_release_file (struct inode * inode, struct file * filp)
{
/* if we are the last writer on the inode, drop the block reservation */
if ((filp->f_mode & FMODE_WRITE) &&
(atomic_read(&inode->i_writecount) == 1))
{
down(&EXT3_I(inode)->truncate_sem);
ext3_discard_reservation(inode);
up(&EXT3_I(inode)->truncate_sem);
}
if (is_dx(inode) && filp->private_data)
ext3_htree_free_dir_info(filp->private_data);
return 0;
}
static ssize_t
ext3_file_write(struct kiocb *iocb, const char __user *buf, size_t count, loff_t pos)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_dentry->d_inode;
ssize_t ret;
int err;
ret = generic_file_aio_write(iocb, buf, count, pos);
/*
* Skip flushing if there was an error, or if nothing was written.
*/
if (ret <= 0)
return ret;
/*
* If the inode is IS_SYNC, or is O_SYNC and we are doing data
* journalling then we need to make sure that we force the transaction
* to disk to keep all metadata uptodate synchronously.
*/
if (file->f_flags & O_SYNC) {
/*
* If we are non-data-journaled, then the dirty data has
* already been flushed to backing store by generic_osync_inode,
* and the inode has been flushed too if there have been any
* modifications other than mere timestamp updates.
*
* Open question --- do we care about flushing timestamps too
* if the inode is IS_SYNC?
*/
if (!ext3_should_journal_data(inode))
return ret;
goto force_commit;
}
/*
* So we know that there has been no forced data flush. If the inode
* is marked IS_SYNC, we need to force one ourselves.
*/
if (!IS_SYNC(inode))
return ret;
/*
* Open question #2 --- should we force data to disk here too? If we
* don't, the only impact is that data=writeback filesystems won't
* flush data to disk automatically on IS_SYNC, only metadata (but
* historically, that is what ext2 has done.)
*/
force_commit:
err = ext3_force_commit(inode->i_sb);
if (err)
return err;
return ret;
}
struct file_operations ext3_file_operations = {
.llseek = generic_file_llseek,
.read = do_sync_read,
.write = do_sync_write,
.aio_read = generic_file_aio_read,
.aio_write = ext3_file_write,
.readv = generic_file_readv,
.writev = generic_file_writev,
.ioctl = ext3_ioctl,
.mmap = generic_file_mmap,
.open = generic_file_open,
.release = ext3_release_file,
.fsync = ext3_sync_file,
.sendfile = generic_file_sendfile,
};
struct inode_operations ext3_file_inode_operations = {
.truncate = ext3_truncate,
.setattr = ext3_setattr,
#ifdef CONFIG_EXT3_FS_XATTR
.setxattr = generic_setxattr,
.getxattr = generic_getxattr,
.listxattr = ext3_listxattr,
.removexattr = generic_removexattr,
#endif
.permission = ext3_permission,
};