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+/*
+ * file.c - NTFS kernel file operations. Part of the Linux-NTFS project.
+ *
+ * Copyright (c) 2001-2004 Anton Altaparmakov
+ *
+ * This program/include file 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/include file 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 (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+
+#include "inode.h"
+#include "debug.h"
+#include "ntfs.h"
+
+/**
+ * ntfs_file_open - called when an inode is about to be opened
+ * @vi: inode to be opened
+ * @filp: file structure describing the inode
+ *
+ * Limit file size to the page cache limit on architectures where unsigned long
+ * is 32-bits. This is the most we can do for now without overflowing the page
+ * cache page index. Doing it this way means we don't run into problems because
+ * of existing too large files. It would be better to allow the user to read
+ * the beginning of the file but I doubt very much anyone is going to hit this
+ * check on a 32-bit architecture, so there is no point in adding the extra
+ * complexity required to support this.
+ *
+ * On 64-bit architectures, the check is hopefully optimized away by the
+ * compiler.
+ *
+ * After the check passes, just call generic_file_open() to do its work.
+ */
+static int ntfs_file_open(struct inode *vi, struct file *filp)
+{
+ if (sizeof(unsigned long) < 8) {
+ if (vi->i_size > MAX_LFS_FILESIZE)
+ return -EFBIG;
+ }
+ return generic_file_open(vi, filp);
+}
+
+#ifdef NTFS_RW
+
+/**
+ * ntfs_file_fsync - sync a file to disk
+ * @filp: file to be synced
+ * @dentry: dentry describing the file to sync
+ * @datasync: if non-zero only flush user data and not metadata
+ *
+ * Data integrity sync of a file to disk. Used for fsync, fdatasync, and msync
+ * system calls. This function is inspired by fs/buffer.c::file_fsync().
+ *
+ * If @datasync is false, write the mft record and all associated extent mft
+ * records as well as the $DATA attribute and then sync the block device.
+ *
+ * If @datasync is true and the attribute is non-resident, we skip the writing
+ * of the mft record and all associated extent mft records (this might still
+ * happen due to the write_inode_now() call).
+ *
+ * Also, if @datasync is true, we do not wait on the inode to be written out
+ * but we always wait on the page cache pages to be written out.
+ *
+ * Note: In the past @filp could be NULL so we ignore it as we don't need it
+ * anyway.
+ *
+ * Locking: Caller must hold i_sem on the inode.
+ *
+ * TODO: We should probably also write all attribute/index inodes associated
+ * with this inode but since we have no simple way of getting to them we ignore
+ * this problem for now.
+ */
+static int ntfs_file_fsync(struct file *filp, struct dentry *dentry,
+ int datasync)
+{
+ struct inode *vi = dentry->d_inode;
+ int err, ret = 0;
+
+ ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
+ BUG_ON(S_ISDIR(vi->i_mode));
+ if (!datasync || !NInoNonResident(NTFS_I(vi)))
+ ret = ntfs_write_inode(vi, 1);
+ write_inode_now(vi, !datasync);
+ err = sync_blockdev(vi->i_sb->s_bdev);
+ if (unlikely(err && !ret))
+ ret = err;
+ if (likely(!ret))
+ ntfs_debug("Done.");
+ else
+ ntfs_warning(vi->i_sb, "Failed to f%ssync inode 0x%lx. Error "
+ "%u.", datasync ? "data" : "", vi->i_ino, -ret);
+ return ret;
+}
+
+#endif /* NTFS_RW */
+
+struct file_operations ntfs_file_ops = {
+ .llseek = generic_file_llseek, /* Seek inside file. */
+ .read = generic_file_read, /* Read from file. */
+ .aio_read = generic_file_aio_read, /* Async read from file. */
+ .readv = generic_file_readv, /* Read from file. */
+#ifdef NTFS_RW
+ .write = generic_file_write, /* Write to file. */
+ .aio_write = generic_file_aio_write, /* Async write to file. */
+ .writev = generic_file_writev, /* Write to file. */
+ /*.release = ,*/ /* Last file is closed. See
+ fs/ext2/file.c::
+ ext2_release_file() for
+ how to use this to discard
+ preallocated space for
+ write opened files. */
+ .fsync = ntfs_file_fsync, /* Sync a file to disk. */
+ /*.aio_fsync = ,*/ /* Sync all outstanding async
+ i/o operations on a
+ kiocb. */
+#endif /* NTFS_RW */
+ /*.ioctl = ,*/ /* Perform function on the
+ mounted filesystem. */
+ .mmap = generic_file_mmap, /* Mmap file. */
+ .open = ntfs_file_open, /* Open file. */
+ .sendfile = generic_file_sendfile, /* Zero-copy data send with
+ the data source being on
+ the ntfs partition. We
+ do not need to care about
+ the data destination. */
+ /*.sendpage = ,*/ /* Zero-copy data send with
+ the data destination being
+ on the ntfs partition. We
+ do not need to care about
+ the data source. */
+};
+
+struct inode_operations ntfs_file_inode_ops = {
+#ifdef NTFS_RW
+ .truncate = ntfs_truncate_vfs,
+ .setattr = ntfs_setattr,
+#endif /* NTFS_RW */
+};
+
+struct file_operations ntfs_empty_file_ops = {};
+
+struct inode_operations ntfs_empty_inode_ops = {};