WSL2-Linux-Kernel/fs/9p/vfs_dir.c

213 строки
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/sched.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_path.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_path.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,
};