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Diffstat (limited to 'fs/ntfs/file.c')
-rw-r--r-- | fs/ntfs/file.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c new file mode 100644 index 0000000..db8713e --- /dev/null +++ b/fs/ntfs/file.c @@ -0,0 +1,155 @@ +/* + * 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 = {}; |