[mirror_ubuntu-zesty-kernel.git] / fs / 9p / vfs_super.c

/*
 *  linux/fs/9p/vfs_super.c
 *
 * This file contians superblock ops for 9P2000. It is intended that
 * you mount this file system on directories.
 *
 *  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 as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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/kernel.h>
#include <linux/config.h>
#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/pagemap.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/idr.h>

#include "debug.h"
#include "v9fs.h"
#include "9p.h"
#include "v9fs_vfs.h"
#include "conv.h"
#include "fid.h"

static void v9fs_clear_inode(struct inode *);
static struct super_operations v9fs_super_ops;

/**
 * v9fs_clear_inode - release an inode
 * @inode: inode to release
 *
 */

static void v9fs_clear_inode(struct inode *inode)
{
	filemap_fdatawrite(inode->i_mapping);
}

/**
 * v9fs_set_super - set the superblock
 * @s: super block
 * @data: file system specific data
 *
 */

static int v9fs_set_super(struct super_block *s, void *data)
{
	s->s_fs_info = data;
	return set_anon_super(s, data);
}

/**
 * v9fs_fill_super - populate superblock with info
 * @sb: superblock
 * @v9ses: session information
 *
 */

static void
v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
		int flags)
{
	sb->s_maxbytes = MAX_LFS_FILESIZE;
	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
	sb->s_blocksize = 1 << sb->s_blocksize_bits;
	sb->s_magic = V9FS_MAGIC;
	sb->s_op = &v9fs_super_ops;

	sb->s_flags = flags | MS_ACTIVE | MS_SYNCHRONOUS | MS_DIRSYNC |
	    MS_NODIRATIME | MS_NOATIME;
}

/**
 * v9fs_get_sb - mount a superblock
 * @fs_type: file system type
 * @flags: mount flags
 * @dev_name: device name that was mounted
 * @data: mount options
 *
 */

static struct super_block *v9fs_get_sb(struct file_system_type
				       *fs_type, int flags,
				       const char *dev_name, void *data)
{
	struct super_block *sb = NULL;
	struct v9fs_fcall *fcall = NULL;
	struct inode *inode = NULL;
	struct dentry *root = NULL;
	struct v9fs_session_info *v9ses = NULL;
	struct v9fs_fid *root_fid = NULL;
	int mode = S_IRWXUGO | S_ISVTX;
	uid_t uid = current->fsuid;
	gid_t gid = current->fsgid;
	int stat_result = 0;
	int newfid = 0;
	int retval = 0;

	dprintk(DEBUG_VFS, " \n");

	v9ses = kcalloc(1, sizeof(struct v9fs_session_info), GFP_KERNEL);
	if (!v9ses)
		return ERR_PTR(-ENOMEM);

	if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
		dprintk(DEBUG_ERROR, "problem initiating session\n");
		retval = newfid;
		goto free_session;
	}

	sb = sget(fs_type, NULL, v9fs_set_super, v9ses);

	v9fs_fill_super(sb, v9ses, flags);

	inode = v9fs_get_inode(sb, S_IFDIR | mode);
	if (IS_ERR(inode)) {
		retval = PTR_ERR(inode);
		goto put_back_sb;
	}

	inode->i_uid = uid;
	inode->i_gid = gid;

	root = d_alloc_root(inode);

	if (!root) {
		retval = -ENOMEM;
		goto release_inode;
	}

	sb->s_root = root;

	/* Setup the Root Inode */
	root_fid = v9fs_fid_create(root);
	if (root_fid == NULL) {
		retval = -ENOMEM;
		goto release_dentry;
	}

	root_fid->fidopen = 0;
	root_fid->v9ses = v9ses;

	stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
	if (stat_result < 0) {
		dprintk(DEBUG_ERROR, "stat error\n");
		v9fs_t_clunk(v9ses, newfid, NULL);
		v9fs_put_idpool(newfid, &v9ses->fidpool);
	} else {
		root_fid->fid = newfid;
		root_fid->qid = fcall->params.rstat.stat->qid;
		root->d_inode->i_ino =
		    v9fs_qid2ino(&fcall->params.rstat.stat->qid);
		v9fs_mistat2inode(fcall->params.rstat.stat, root->d_inode, sb);
	}

	kfree(fcall);

	if (stat_result < 0) {
		retval = stat_result;
		goto release_dentry;
	}

	return sb;

      release_dentry:
	dput(sb->s_root);

      release_inode:
	iput(inode);

      put_back_sb:
	up_write(&sb->s_umount);
	deactivate_super(sb);
	v9fs_session_close(v9ses);

      free_session:
	kfree(v9ses);

	return ERR_PTR(retval);
}

/**
 * v9fs_kill_super - Kill Superblock
 * @s: superblock
 *
 */

static void v9fs_kill_super(struct super_block *s)
{
	struct v9fs_session_info *v9ses = s->s_fs_info;

	dprintk(DEBUG_VFS, " %p\n", s);

	v9fs_dentry_release(s->s_root);	/* clunk root */

	kill_anon_super(s);

	v9fs_session_close(v9ses);
	kfree(v9ses);
	dprintk(DEBUG_VFS, "exiting kill_super\n");
}

/**
 * v9fs_show_options - Show mount options in /proc/mounts
 * @m: seq_file to write to
 * @mnt: mount descriptor
 *
 */

static int v9fs_show_options(struct seq_file *m, struct vfsmount *mnt)
{
	struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;

	if (v9ses->debug != 0)
		seq_printf(m, ",debug=%u", v9ses->debug);
	if (v9ses->port != V9FS_PORT)
		seq_printf(m, ",port=%u", v9ses->port);
	if (v9ses->maxdata != 9000)
		seq_printf(m, ",msize=%u", v9ses->maxdata);
	if (v9ses->afid != ~0)
		seq_printf(m, ",afid=%u", v9ses->afid);
	if (v9ses->proto == PROTO_UNIX)
		seq_puts(m, ",proto=unix");
	if (v9ses->extended == 0)
		seq_puts(m, ",noextend");
	if (v9ses->nodev == 1)
		seq_puts(m, ",nodevmap");
	seq_printf(m, ",name=%s", v9ses->name);
	seq_printf(m, ",aname=%s", v9ses->remotename);
	seq_printf(m, ",uid=%u", v9ses->uid);
	seq_printf(m, ",gid=%u", v9ses->gid);
	return 0;
}

static void
v9fs_umount_begin(struct super_block *sb)
{
	struct v9fs_session_info *v9ses = sb->s_fs_info;

	v9fs_session_cancel(v9ses);
}

static struct super_operations v9fs_super_ops = {
	.statfs = simple_statfs,
	.clear_inode = v9fs_clear_inode,
	.show_options = v9fs_show_options,
	.umount_begin = v9fs_umount_begin,
};

struct file_system_type v9fs_fs_type = {
	.name = "9P",
	.get_sb = v9fs_get_sb,
	.kill_sb = v9fs_kill_super,
	.owner = THIS_MODULE,
};
Commit	Line	Data
9e82cf6a EVH	1	/*
	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
	11	* it under the terms of the GNU General Public License as published by
	12	* the Free Software Foundation; either version 2 of the License, or
	13	* (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful,
	16	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	* GNU General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to:
	22	* Free Software Foundation
	23	* 51 Franklin Street, Fifth Floor
	24	* Boston, MA 02111-1301 USA
	25	*
	26	*/
	27
	28	#include <linux/kernel.h>
	29	#include <linux/config.h>
	30	#include <linux/module.h>
	31	#include <linux/errno.h>
	32	#include <linux/fs.h>
	33	#include <linux/file.h>
	34	#include <linux/stat.h>
	35	#include <linux/string.h>
	36	#include <linux/smp_lock.h>
	37	#include <linux/inet.h>
	38	#include <linux/pagemap.h>
	39	#include <linux/seq_file.h>
	40	#include <linux/mount.h>
	41	#include <linux/idr.h>
	42
	43	#include "debug.h"
	44	#include "v9fs.h"
	45	#include "9p.h"
	46	#include "v9fs_vfs.h"
	47	#include "conv.h"
	48	#include "fid.h"
	49
	50	static void v9fs_clear_inode(struct inode *);
	51	static struct super_operations v9fs_super_ops;
	52
	53	/**
	54	* v9fs_clear_inode - release an inode
	55	* @inode: inode to release
	56	*
	57	*/
	58
	59	static void v9fs_clear_inode(struct inode *inode)
	60	{
	61	filemap_fdatawrite(inode->i_mapping);
	62	}
	63
	64	/**
65	* v9fs_set_super - set the superblock
66	* @s: super block
67	* @data: file system specific data
68	*
69	*/
70
71	static int v9fs_set_super(struct super_block s, void data)
72	{
73	s->s_fs_info = data;
74	return set_anon_super(s, data);
75	}
76
77	/**
78	* v9fs_fill_super - populate superblock with info
79	* @sb: superblock
80	* @v9ses: session information
81	*
82	*/
83
84	static void
85	v9fs_fill_super(struct super_block sb, struct v9fs_session_info v9ses,
86	int flags)
87	{
88	sb->s_maxbytes = MAX_LFS_FILESIZE;
89	sb->s_blocksize_bits = fls(v9ses->maxdata - 1);
90	sb->s_blocksize = 1 << sb->s_blocksize_bits;
91	sb->s_magic = V9FS_MAGIC;
92	sb->s_op = &v9fs_super_ops;
93
94	sb->s_flags = flags \| MS_ACTIVE \| MS_SYNCHRONOUS \| MS_DIRSYNC \|
95	MS_NODIRATIME \| MS_NOATIME;
96	}
97
98	/**
99	* v9fs_get_sb - mount a superblock
100	* @fs_type: file system type
101	* @flags: mount flags
102	* @dev_name: device name that was mounted
103	* @data: mount options
104	*
105	*/
106
107	static struct super_block *v9fs_get_sb(struct file_system_type
108	*fs_type, int flags,
109	const char dev_name, void data)
110	{
111	struct super_block *sb = NULL;
112	struct v9fs_fcall *fcall = NULL;
113	struct inode *inode = NULL;
114	struct dentry *root = NULL;
115	struct v9fs_session_info *v9ses = NULL;
116	struct v9fs_fid *root_fid = NULL;
117	int mode = S_IRWXUGO \| S_ISVTX;
118	uid_t uid = current->fsuid;
119	gid_t gid = current->fsgid;
120	int stat_result = 0;
121	int newfid = 0;
122	int retval = 0;
123
124	dprintk(DEBUG_VFS, " \n");
125
126	v9ses = kcalloc(1, sizeof(struct v9fs_session_info), GFP_KERNEL);
127	if (!v9ses)
128	return ERR_PTR(-ENOMEM);
129
130	if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
131	dprintk(DEBUG_ERROR, "problem initiating session\n");
132	retval = newfid;
133	goto free_session;
134	}
135
136	sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
137
138	v9fs_fill_super(sb, v9ses, flags);
139
140	inode = v9fs_get_inode(sb, S_IFDIR \| mode);
141	if (IS_ERR(inode)) {
142	retval = PTR_ERR(inode);
143	goto put_back_sb;
144	}
145
146	inode->i_uid = uid;
147	inode->i_gid = gid;
148
149	root = d_alloc_root(inode);
150
151	if (!root) {
152	retval = -ENOMEM;
153	goto release_inode;
154	}
155
156	sb->s_root = root;
157
158	/* Setup the Root Inode */
159	root_fid = v9fs_fid_create(root);
160	if (root_fid == NULL) {
161	retval = -ENOMEM;
162	goto release_dentry;
163	}
164
165	root_fid->fidopen = 0;
166	root_fid->v9ses = v9ses;
167
168	stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
169	if (stat_result < 0) {
170	dprintk(DEBUG_ERROR, "stat error\n");
171	v9fs_t_clunk(v9ses, newfid, NULL);
172	v9fs_put_idpool(newfid, &v9ses->fidpool);
173	} else {
174	root_fid->fid = newfid;
175	root_fid->qid = fcall->params.rstat.stat->qid;
176	root->d_inode->i_ino =
177	v9fs_qid2ino(&fcall->params.rstat.stat->qid);
178	v9fs_mistat2inode(fcall->params.rstat.stat, root->d_inode, sb);
179	}
180
181	kfree(fcall);
182
183	if (stat_result < 0) {
184	retval = stat_result;
185	goto release_dentry;
186	}
187
188	return sb;
189
190	release_dentry:
191	dput(sb->s_root);
192
193	release_inode:
194	iput(inode);
195
196	put_back_sb:
197	up_write(&sb->s_umount);
198	deactivate_super(sb);
199	v9fs_session_close(v9ses);
200
201	free_session:
202	kfree(v9ses);
203
204	return ERR_PTR(retval);
205	}
206
207	/**
208	* v9fs_kill_super - Kill Superblock
209	* @s: superblock
210	*
211	*/
212
213	static void v9fs_kill_super(struct super_block *s)
214	{
215	struct v9fs_session_info *v9ses = s->s_fs_info;
216
217	dprintk(DEBUG_VFS, " %p\n", s);
218
219	v9fs_dentry_release(s->s_root); /* clunk root */
220
221	kill_anon_super(s);
222
223	v9fs_session_close(v9ses);
224	kfree(v9ses);
225	dprintk(DEBUG_VFS, "exiting kill_super\n");
226	}
227
228	/**
229	* v9fs_show_options - Show mount options in /proc/mounts
230	* @m: seq_file to write to
231	* @mnt: mount descriptor
232	*
233	*/
234
235	static int v9fs_show_options(struct seq_file m, struct vfsmount mnt)
236	{
237	struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
238
239	if (v9ses->debug != 0)
240	seq_printf(m, ",debug=%u", v9ses->debug);
241	if (v9ses->port != V9FS_PORT)
242	seq_printf(m, ",port=%u", v9ses->port);
243	if (v9ses->maxdata != 9000)
244	seq_printf(m, ",msize=%u", v9ses->maxdata);
245	if (v9ses->afid != ~0)
246	seq_printf(m, ",afid=%u", v9ses->afid);
247	if (v9ses->proto == PROTO_UNIX)
248	seq_puts(m, ",proto=unix");
249	if (v9ses->extended == 0)
250	seq_puts(m, ",noextend");
251	if (v9ses->nodev == 1)
252	seq_puts(m, ",nodevmap");
253	seq_printf(m, ",name=%s", v9ses->name);
254	seq_printf(m, ",aname=%s", v9ses->remotename);
255	seq_printf(m, ",uid=%u", v9ses->uid);
256	seq_printf(m, ",gid=%u", v9ses->gid);
257	return 0;
258	}
259
322b329a EVH	260	static void
	261	v9fs_umount_begin(struct super_block *sb)
	262	{
	263	struct v9fs_session_info *v9ses = sb->s_fs_info;
	264
	265	v9fs_session_cancel(v9ses);
	266	}
	267
9e82cf6a EVH	268	static struct super_operations v9fs_super_ops = {
	269	.statfs = simple_statfs,
	270	.clear_inode = v9fs_clear_inode,
	271	.show_options = v9fs_show_options,
322b329a	272	.umount_begin = v9fs_umount_begin,
9e82cf6a EVH	273	};
	274
	275	struct file_system_type v9fs_fs_type = {
	276	.name = "9P",
	277	.get_sb = v9fs_get_sb,
	278	.kill_sb = v9fs_kill_super,
	279	.owner = THIS_MODULE,
	280	};