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Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -07001/*
2 * linux/fs/9p/vfs_super.c
3 *
4 * This file contians superblock ops for 9P2000. It is intended that
5 * you mount this file system on directories.
6 *
7 * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
8 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
9 *
10 * This program is free software; you can redistribute it and/or modify
Eric Van Hensbergen42e8c502006-03-25 03:07:28 -080011 * it under the terms of the GNU General Public License version 2
12 * as published by the Free Software Foundation.
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070013 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to:
21 * Free Software Foundation
22 * 51 Franklin Street, Fifth Floor
23 * Boston, MA 02111-1301 USA
24 *
25 */
26
27#include <linux/kernel.h>
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070028#include <linux/module.h>
29#include <linux/errno.h>
30#include <linux/fs.h>
31#include <linux/file.h>
32#include <linux/stat.h>
33#include <linux/string.h>
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070034#include <linux/inet.h>
35#include <linux/pagemap.h>
36#include <linux/seq_file.h>
37#include <linux/mount.h>
38#include <linux/idr.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040039#include <linux/sched.h>
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -050040#include <net/9p/9p.h>
41#include <net/9p/client.h>
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070042
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070043#include "v9fs.h"
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070044#include "v9fs_vfs.h"
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070045#include "fid.h"
46
47static void v9fs_clear_inode(struct inode *);
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -080048static const struct super_operations v9fs_super_ops;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070049
50/**
51 * v9fs_clear_inode - release an inode
52 * @inode: inode to release
53 *
54 */
55
56static void v9fs_clear_inode(struct inode *inode)
57{
58 filemap_fdatawrite(inode->i_mapping);
59}
60
61/**
62 * v9fs_set_super - set the superblock
63 * @s: super block
64 * @data: file system specific data
65 *
66 */
67
68static int v9fs_set_super(struct super_block *s, void *data)
69{
70 s->s_fs_info = data;
71 return set_anon_super(s, data);
72}
73
74/**
75 * v9fs_fill_super - populate superblock with info
76 * @sb: superblock
77 * @v9ses: session information
Eric Van Hensbergenee443992008-03-05 07:08:09 -060078 * @flags: flags propagated from v9fs_get_sb()
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070079 *
80 */
81
82static void
83v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
84 int flags)
85{
86 sb->s_maxbytes = MAX_LFS_FILESIZE;
87 sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
88 sb->s_blocksize = 1 << sb->s_blocksize_bits;
89 sb->s_magic = V9FS_MAGIC;
90 sb->s_op = &v9fs_super_ops;
91
92 sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
Christoph Hellwig0d456fa2006-01-09 20:52:15 -080093 MS_NOATIME;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -070094}
95
96/**
97 * v9fs_get_sb - mount a superblock
98 * @fs_type: file system type
99 * @flags: mount flags
100 * @dev_name: device name that was mounted
101 * @data: mount options
David Howells454e2392006-06-23 02:02:57 -0700102 * @mnt: mountpoint record to be instantiated
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700103 *
104 */
105
David Howells454e2392006-06-23 02:02:57 -0700106static int v9fs_get_sb(struct file_system_type *fs_type, int flags,
107 const char *dev_name, void *data,
108 struct vfsmount *mnt)
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700109{
110 struct super_block *sb = NULL;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700111 struct inode *inode = NULL;
112 struct dentry *root = NULL;
113 struct v9fs_session_info *v9ses = NULL;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500114 struct p9_stat *st = NULL;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700115 int mode = S_IRWXUGO | S_ISVTX;
116 uid_t uid = current->fsuid;
117 gid_t gid = current->fsgid;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500118 struct p9_fid *fid;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700119 int retval = 0;
120
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500121 P9_DPRINTK(P9_DEBUG_VFS, " \n");
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700122
Latchesar Ionkovdda6b022007-11-06 08:02:53 -0600123 st = NULL;
Latchesar Ionkov1dac06b2006-01-08 01:05:02 -0800124 v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700125 if (!v9ses)
David Howells454e2392006-06-23 02:02:57 -0700126 return -ENOMEM;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700127
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500128 fid = v9fs_session_init(v9ses, dev_name, data);
129 if (IS_ERR(fid)) {
130 retval = PTR_ERR(fid);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500131 goto close_session;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500132 }
133
134 st = p9_client_stat(fid);
135 if (IS_ERR(st)) {
136 retval = PTR_ERR(st);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500137 goto clunk_fid;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700138 }
139
140 sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
David Howells454e2392006-06-23 02:02:57 -0700141 if (IS_ERR(sb)) {
142 retval = PTR_ERR(sb);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500143 goto free_stat;
David Howells454e2392006-06-23 02:02:57 -0700144 }
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700145 v9fs_fill_super(sb, v9ses, flags);
146
147 inode = v9fs_get_inode(sb, S_IFDIR | mode);
148 if (IS_ERR(inode)) {
149 retval = PTR_ERR(inode);
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500150 goto release_sb;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700151 }
152
153 inode->i_uid = uid;
154 inode->i_gid = gid;
155
156 root = d_alloc_root(inode);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700157 if (!root) {
158 retval = -ENOMEM;
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500159 goto release_sb;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700160 }
161
162 sb->s_root = root;
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500163 root->d_inode->i_ino = v9fs_qid2ino(&st->qid);
164 v9fs_stat2inode(st, root->d_inode, sb);
165 v9fs_fid_add(root, fid);
Latchesar Ionkovdda6b022007-11-06 08:02:53 -0600166 kfree(st);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700167
David Howells454e2392006-06-23 02:02:57 -0700168 return simple_set_mnt(mnt, sb);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700169
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500170release_sb:
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500171 if (sb) {
172 up_write(&sb->s_umount);
173 deactivate_super(sb);
174 }
175
Eric Van Hensbergen887b3ec2008-05-08 20:26:37 -0500176free_stat:
177 kfree(st);
178
179clunk_fid:
180 p9_client_clunk(fid);
181
182close_session:
183 v9fs_session_close(v9ses);
184 kfree(v9ses);
185
David Howells454e2392006-06-23 02:02:57 -0700186 return retval;
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700187}
188
189/**
190 * v9fs_kill_super - Kill Superblock
191 * @s: superblock
192 *
193 */
194
195static void v9fs_kill_super(struct super_block *s)
196{
197 struct v9fs_session_info *v9ses = s->s_fs_info;
198
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500199 P9_DPRINTK(P9_DEBUG_VFS, " %p\n", s);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700200
201 v9fs_dentry_release(s->s_root); /* clunk root */
202
203 kill_anon_super(s);
204
205 v9fs_session_close(v9ses);
206 kfree(v9ses);
Latchesar Ionkovbd238fb2007-07-10 17:57:28 -0500207 P9_DPRINTK(P9_DEBUG_VFS, "exiting kill_super\n");
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700208}
209
210/**
211 * v9fs_show_options - Show mount options in /proc/mounts
212 * @m: seq_file to write to
213 * @mnt: mount descriptor
214 *
215 */
216
217static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
218{
219 struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
220
Eric Van Hensbergena80d9232007-10-17 14:31:07 -0500221 seq_printf(m, "%s", v9ses->options);
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700222 return 0;
223}
224
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700225static void
Al Viro42faad92008-04-24 07:21:56 -0400226v9fs_umount_begin(struct super_block *sb)
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700227{
Al Viro42faad92008-04-24 07:21:56 -0400228 struct v9fs_session_info *v9ses = sb->s_fs_info;
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700229
Al Viro42faad92008-04-24 07:21:56 -0400230 v9fs_session_cancel(v9ses);
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700231}
232
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800233static const struct super_operations v9fs_super_ops = {
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700234 .statfs = simple_statfs,
235 .clear_inode = v9fs_clear_inode,
236 .show_options = v9fs_show_options,
Eric Van Hensbergen322b3292005-09-09 13:04:23 -0700237 .umount_begin = v9fs_umount_begin,
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700238};
239
240struct file_system_type v9fs_fs_type = {
Eric Van Hensbergen67543e52006-03-25 03:07:29 -0800241 .name = "9p",
Eric Van Hensbergen9e82cf62005-09-09 13:04:20 -0700242 .get_sb = v9fs_get_sb,
243 .kill_sb = v9fs_kill_super,
244 .owner = THIS_MODULE,
245};