linux/fs/9p/vfs_dir.c
Arjan van de Ven 4b6f5d20b0 [PATCH] Make most file operations structs in fs/ const
This is a conversion to make the various file_operations structs in fs/
const.  Basically a regexp job, with a few manual fixups

The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:06 -08:00

212 lines
4.6 KiB
C

/*
* linux/fs/9p/vfs_dir.c
*
* This file contains vfs directory ops for the 9P2000 protocol.
*
* Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
* Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*
* 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:
* Free Software Foundation
* 51 Franklin Street, Fifth Floor
* Boston, MA 02111-1301 USA
*
*/
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/stat.h>
#include <linux/string.h>
#include <linux/smp_lock.h>
#include <linux/inet.h>
#include <linux/idr.h>
#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "conv.h"
#include "v9fs_vfs.h"
#include "fid.h"
/**
* dt_type - return file type
* @mistat: mistat structure
*
*/
static inline int dt_type(struct v9fs_stat *mistat)
{
unsigned long perm = mistat->mode;
int rettype = DT_REG;
if (perm & V9FS_DMDIR)
rettype = DT_DIR;
if (perm & V9FS_DMSYMLINK)
rettype = DT_LNK;
return rettype;
}
/**
* v9fs_dir_readdir - read a directory
* @filep: opened file structure
* @dirent: directory structure ???
* @filldir: function to populate directory structure ???
*
*/
static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
{
struct v9fs_fcall *fcall = NULL;
struct inode *inode = filp->f_dentry->d_inode;
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
struct v9fs_fid *file = filp->private_data;
unsigned int i, n, s;
int fid = -1;
int ret = 0;
struct v9fs_stat stat;
int over = 0;
dprintk(DEBUG_VFS, "name %s\n", filp->f_dentry->d_name.name);
fid = file->fid;
if (file->rdir_fcall && (filp->f_pos != file->rdir_pos)) {
kfree(file->rdir_fcall);
file->rdir_fcall = NULL;
}
if (file->rdir_fcall) {
n = file->rdir_fcall->params.rread.count;
i = file->rdir_fpos;
while (i < n) {
s = v9fs_deserialize_stat(
file->rdir_fcall->params.rread.data + i,
n - i, &stat, v9ses->extended);
if (s == 0) {
dprintk(DEBUG_ERROR,
"error while deserializing stat\n");
ret = -EIO;
goto FreeStructs;
}
over = filldir(dirent, stat.name.str, stat.name.len,
filp->f_pos, v9fs_qid2ino(&stat.qid),
dt_type(&stat));
if (over) {
file->rdir_fpos = i;
file->rdir_pos = filp->f_pos;
break;
}
i += s;
filp->f_pos += s;
}
if (!over) {
kfree(file->rdir_fcall);
file->rdir_fcall = NULL;
}
}
while (!over) {
ret = v9fs_t_read(v9ses, fid, filp->f_pos,
v9ses->maxdata-V9FS_IOHDRSZ, &fcall);
if (ret < 0) {
dprintk(DEBUG_ERROR, "error while reading: %d: %p\n",
ret, fcall);
goto FreeStructs;
} else if (ret == 0)
break;
n = ret;
i = 0;
while (i < n) {
s = v9fs_deserialize_stat(fcall->params.rread.data + i,
n - i, &stat, v9ses->extended);
if (s == 0) {
dprintk(DEBUG_ERROR,
"error while deserializing stat\n");
return -EIO;
}
over = filldir(dirent, stat.name.str, stat.name.len,
filp->f_pos, v9fs_qid2ino(&stat.qid),
dt_type(&stat));
if (over) {
file->rdir_fcall = fcall;
file->rdir_fpos = i;
file->rdir_pos = filp->f_pos;
fcall = NULL;
break;
}
i += s;
filp->f_pos += s;
}
kfree(fcall);
}
FreeStructs:
kfree(fcall);
return ret;
}
/**
* v9fs_dir_release - close a directory
* @inode: inode of the directory
* @filp: file pointer to a directory
*
*/
int v9fs_dir_release(struct inode *inode, struct file *filp)
{
struct v9fs_session_info *v9ses = v9fs_inode2v9ses(inode);
struct v9fs_fid *fid = filp->private_data;
int fidnum = -1;
dprintk(DEBUG_VFS, "inode: %p filp: %p fid: %d\n", inode, filp,
fid->fid);
fidnum = fid->fid;
filemap_write_and_wait(inode->i_mapping);
if (fidnum >= 0) {
dprintk(DEBUG_VFS, "fidopen: %d v9f->fid: %d\n", fid->fidopen,
fid->fid);
if (v9fs_t_clunk(v9ses, fidnum))
dprintk(DEBUG_ERROR, "clunk failed\n");
kfree(fid->rdir_fcall);
kfree(fid);
filp->private_data = NULL;
}
return 0;
}
const struct file_operations v9fs_dir_operations = {
.read = generic_read_dir,
.readdir = v9fs_dir_readdir,
.open = v9fs_file_open,
.release = v9fs_dir_release,
};