vfs_dir.c revision 02da398b950c5d079c20afaa23f322383e96070a 
1/*
2 * linux/fs/9p/vfs_dir.c
3 *
4 * This file contains vfs directory ops for the 9P2000 protocol.
5 *
6 *  Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
7 *  Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
8 *
9 *  This program is free software; you can redistribute it and/or modify
10 *  it under the terms of the GNU General Public License version 2
11 *  as published by the Free Software Foundation.
12 *
13 *  This program is distributed in the hope that it will be useful,
14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *  GNU General Public License for more details.
17 *
18 *  You should have received a copy of the GNU General Public License
19 *  along with this program; if not, write to:
20 *  Free Software Foundation
21 *  51 Franklin Street, Fifth Floor
22 *  Boston, MA  02111-1301  USA
23 *
24 */
25
26#include <linux/module.h>
27#include <linux/errno.h>
28#include <linux/fs.h>
29#include <linux/file.h>
30#include <linux/stat.h>
31#include <linux/string.h>
32#include <linux/sched.h>
33#include <linux/inet.h>
34#include <linux/idr.h>
35#include <net/9p/9p.h>
36#include <net/9p/client.h>
37
38#include "v9fs.h"
39#include "v9fs_vfs.h"
40#include "fid.h"
41
42/**
43 * dt_type - return file type
44 * @mistat: mistat structure
45 *
46 */
47
48static inline int dt_type(struct p9_wstat *mistat)
49{
50	unsigned long perm = mistat->mode;
51	int rettype = DT_REG;
52
53	if (perm & P9_DMDIR)
54		rettype = DT_DIR;
55	if (perm & P9_DMSYMLINK)
56		rettype = DT_LNK;
57
58	return rettype;
59}
60
61/**
62 * v9fs_dir_readdir - read a directory
63 * @filp: opened file structure
64 * @dirent: directory structure ???
65 * @filldir: function to populate directory structure ???
66 *
67 */
68
69static int v9fs_dir_readdir(struct file *filp, void *dirent, filldir_t filldir)
70{
71	int over;
72	struct p9_wstat st;
73	int err;
74	struct p9_fid *fid;
75	int buflen;
76	char *statbuf;
77	int n, i = 0;
78
79	P9_DPRINTK(P9_DEBUG_VFS, "name %s\n", filp->f_path.dentry->d_name.name);
80	fid = filp->private_data;
81
82	buflen = fid->clnt->msize - P9_IOHDRSZ;
83	statbuf = kmalloc(buflen, GFP_KERNEL);
84	if (!statbuf)
85		return -ENOMEM;
86
87	while (1) {
88		err = v9fs_file_readn(filp, statbuf, NULL, buflen,
89								fid->rdir_fpos);
90		if (err <= 0)
91			break;
92
93		n = err;
94		while (i < n) {
95			err = p9stat_read(statbuf + i, buflen-i, &st,
96							fid->clnt->dotu);
97			if (err) {
98				P9_DPRINTK(P9_DEBUG_VFS, "returned %d\n", err);
99				err = -EIO;
100				p9stat_free(&st);
101				goto free_and_exit;
102			}
103
104			i += st.size+2;
105			fid->rdir_fpos += st.size+2;
106
107			over = filldir(dirent, st.name, strlen(st.name),
108			    filp->f_pos, v9fs_qid2ino(&st.qid), dt_type(&st));
109
110			filp->f_pos += st.size+2;
111
112			p9stat_free(&st);
113
114			if (over) {
115				err = 0;
116				goto free_and_exit;
117			}
118		}
119	}
120
121free_and_exit:
122	kfree(statbuf);
123	return err;
124}
125
126
127/**
128 * v9fs_dir_release - close a directory
129 * @inode: inode of the directory
130 * @filp: file pointer to a directory
131 *
132 */
133
134int v9fs_dir_release(struct inode *inode, struct file *filp)
135{
136	struct p9_fid *fid;
137
138	fid = filp->private_data;
139	P9_DPRINTK(P9_DEBUG_VFS,
140			"inode: %p filp: %p fid: %d\n", inode, filp, fid->fid);
141	filemap_write_and_wait(inode->i_mapping);
142	p9_client_clunk(fid);
143	return 0;
144}
145
146const struct file_operations v9fs_dir_operations = {
147	.read = generic_read_dir,
148	.llseek = generic_file_llseek,
149	.readdir = v9fs_dir_readdir,
150	.open = v9fs_file_open,
151	.release = v9fs_dir_release,
152};
153