xref: /openbmc/linux/fs/9p/vfs_dir.c (revision 8569c914)
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 
48 static 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 
69 static 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 
121 free_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 
134 int 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 
146 const 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