[GitHub/mt8127/android_kernel_alcatel_ttab.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 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/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 "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_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 = kzalloc(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");
		kfree(v9ses);
		return ERR_PTR(newfid);
	}

	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 put_back_sb;
	}

	sb->s_root = root;

	stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
	if (stat_result < 0) {
		dprintk(DEBUG_ERROR, "stat error\n");
		v9fs_t_clunk(v9ses, newfid);
	} else {
		/* Setup the Root Inode */
		root_fid = v9fs_fid_create(v9ses, newfid);
		if (root_fid == NULL) {
			retval = -ENOMEM;
			goto put_back_sb;
		}

		retval = v9fs_fid_insert(root_fid, root);
		if (retval < 0) {
			kfree(fcall);
			goto put_back_sb;
		}

		root_fid->qid = fcall->params.rstat.stat.qid;
		root->d_inode->i_ino =
		    v9fs_qid2ino(&fcall->params.rstat.stat.qid);
		v9fs_stat2inode(&fcall->params.rstat.stat, root->d_inode, sb);
	}

	kfree(fcall);

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

	return sb;

put_back_sb:
	/* deactivate_super calls v9fs_kill_super which will frees the rest */
	up_write(&sb->s_umount);
	deactivate_super(sb);
	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
42e8c509 EVH	11	* it under the terms of the GNU General Public License version 2
42e8c509 EVH	12	* as published by the Free Software Foundation.
9e82cf6a EVH	13	*
	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>
	28	#include <linux/config.h>
	29	#include <linux/module.h>
	30	#include <linux/errno.h>
	31	#include <linux/fs.h>
	32	#include <linux/file.h>
	33	#include <linux/stat.h>
	34	#include <linux/string.h>
	35	#include <linux/smp_lock.h>
	36	#include <linux/inet.h>
	37	#include <linux/pagemap.h>
	38	#include <linux/seq_file.h>
	39	#include <linux/mount.h>
	40	#include <linux/idr.h>
	41
	42	#include "debug.h"
	43	#include "v9fs.h"
	44	#include "9p.h"
	45	#include "v9fs_vfs.h"
9e82cf6a EVH	46	#include "fid.h"
	47
	48	static void v9fs_clear_inode(struct inode *);
	49	static struct super_operations v9fs_super_ops;
	50
	51	/**
	52	* v9fs_clear_inode - release an inode
	53	* @inode: inode to release
	54	*
	55	*/
	56
	57	static void v9fs_clear_inode(struct inode *inode)
	58	{
	59	filemap_fdatawrite(inode->i_mapping);
	60	}
	61
	62	/**
	63	* v9fs_set_super - set the superblock
	64	* @s: super block
	65	* @data: file system specific data
	66	*
	67	*/
	68
	69	static int v9fs_set_super(struct super_block s, void data)
	70	{
	71	s->s_fs_info = data;
	72	return set_anon_super(s, data);
	73	}
	74
	75	/**
	76	* v9fs_fill_super - populate superblock with info
	77	* @sb: superblock
	78	* @v9ses: session information
	79	*
	80	*/
	81
	82	static void
	83	v9fs_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 \|
0d456fa4	93	MS_NOATIME;
9e82cf6a EVH	94	}
	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
	102	*
	103	*/
	104
	105	static struct super_block *v9fs_get_sb(struct file_system_type
	106	*fs_type, int flags,
	107	const char dev_name, void data)
	108	{
	109	struct super_block *sb = NULL;
	110	struct v9fs_fcall *fcall = NULL;
	111	struct inode *inode = NULL;
	112	struct dentry *root = NULL;
	113	struct v9fs_session_info *v9ses = NULL;
	114	struct v9fs_fid *root_fid = NULL;
	115	int mode = S_IRWXUGO \| S_ISVTX;
	116	uid_t uid = current->fsuid;
	117	gid_t gid = current->fsgid;
	118	int stat_result = 0;
	119	int newfid = 0;
	120	int retval = 0;
	121
	122	dprintk(DEBUG_VFS, " \n");
	123
1dac06b2	124	v9ses = kzalloc(sizeof(struct v9fs_session_info), GFP_KERNEL);
9e82cf6a EVH	125	if (!v9ses)
	126	return ERR_PTR(-ENOMEM);
	127
	128	if ((newfid = v9fs_session_init(v9ses, dev_name, data)) < 0) {
	129	dprintk(DEBUG_ERROR, "problem initiating session\n");
3cf6429a	130	kfree(v9ses);
192eaa28	131	return ERR_PTR(newfid);
9e82cf6a EVH	132	}
	133
	134	sb = sget(fs_type, NULL, v9fs_set_super, v9ses);
	135
	136	v9fs_fill_super(sb, v9ses, flags);
	137
	138	inode = v9fs_get_inode(sb, S_IFDIR \| mode);
	139	if (IS_ERR(inode)) {
	140	retval = PTR_ERR(inode);
	141	goto put_back_sb;
	142	}
	143
	144	inode->i_uid = uid;
	145	inode->i_gid = gid;
	146
	147	root = d_alloc_root(inode);
9e82cf6a EVH	148	if (!root) {
9e82cf6a EVH	149	retval = -ENOMEM;
f71626a4	150	goto put_back_sb;
9e82cf6a EVH	151	}
	152
	153	sb->s_root = root;
	154
9e82cf6a EVH	155	stat_result = v9fs_t_stat(v9ses, newfid, &fcall);
	156	if (stat_result < 0) {
	157	dprintk(DEBUG_ERROR, "stat error\n");
3cf6429a	158	v9fs_t_clunk(v9ses, newfid);
9e82cf6a	159	} else {
0b8dd177	160	/* Setup the Root Inode */
6a3124a3	161	root_fid = v9fs_fid_create(v9ses, newfid);
0b8dd177 LI	162	if (root_fid == NULL) {
	163	retval = -ENOMEM;
	164	goto put_back_sb;
	165	}
	166
6a3124a3	167	retval = v9fs_fid_insert(root_fid, root);
74b8054c EVH	168	if (retval < 0) {
74b8054c EVH	169	kfree(fcall);
6a3124a3	170	goto put_back_sb;
74b8054c	171	}
6a3124a3	172
531b1094	173	root_fid->qid = fcall->params.rstat.stat.qid;
9e82cf6a	174	root->d_inode->i_ino =
531b1094 LI	175	v9fs_qid2ino(&fcall->params.rstat.stat.qid);
531b1094 LI	176	v9fs_stat2inode(&fcall->params.rstat.stat, root->d_inode, sb);
9e82cf6a EVH	177	}
9e82cf6a EVH	178
74b8054c EVH	179	kfree(fcall);
74b8054c EVH	180
9e82cf6a EVH	181	if (stat_result < 0) {
9e82cf6a EVH	182	retval = stat_result;
f71626a4	183	goto put_back_sb;
9e82cf6a EVH	184	}
	185
	186	return sb;
	187
f71626a4 LI	188	put_back_sb:
f71626a4 LI	189	/* deactivate_super calls v9fs_kill_super which will frees the rest */
9e82cf6a EVH	190	up_write(&sb->s_umount);
9e82cf6a EVH	191	deactivate_super(sb);
9e82cf6a EVH	192	return ERR_PTR(retval);
	193	}
	194
	195	/**
	196	* v9fs_kill_super - Kill Superblock
	197	* @s: superblock
	198	*
	199	*/
	200
	201	static void v9fs_kill_super(struct super_block *s)
	202	{
	203	struct v9fs_session_info *v9ses = s->s_fs_info;
	204
	205	dprintk(DEBUG_VFS, " %p\n", s);
	206
	207	v9fs_dentry_release(s->s_root); /* clunk root */
	208
	209	kill_anon_super(s);
	210
	211	v9fs_session_close(v9ses);
	212	kfree(v9ses);
	213	dprintk(DEBUG_VFS, "exiting kill_super\n");
	214	}
	215
	216	/**
	217	* v9fs_show_options - Show mount options in /proc/mounts
	218	* @m: seq_file to write to
	219	* @mnt: mount descriptor
	220	*
	221	*/
	222
	223	static int v9fs_show_options(struct seq_file m, struct vfsmount mnt)
	224	{
	225	struct v9fs_session_info *v9ses = mnt->mnt_sb->s_fs_info;
	226
	227	if (v9ses->debug != 0)
	228	seq_printf(m, ",debug=%u", v9ses->debug);
	229	if (v9ses->port != V9FS_PORT)
	230	seq_printf(m, ",port=%u", v9ses->port);
	231	if (v9ses->maxdata != 9000)
	232	seq_printf(m, ",msize=%u", v9ses->maxdata);
	233	if (v9ses->afid != ~0)
	234	seq_printf(m, ",afid=%u", v9ses->afid);
	235	if (v9ses->proto == PROTO_UNIX)
	236	seq_puts(m, ",proto=unix");
	237	if (v9ses->extended == 0)
	238	seq_puts(m, ",noextend");
	239	if (v9ses->nodev == 1)
	240	seq_puts(m, ",nodevmap");
	241	seq_printf(m, ",name=%s", v9ses->name);
	242	seq_printf(m, ",aname=%s", v9ses->remotename);
	243	seq_printf(m, ",uid=%u", v9ses->uid);
	244	seq_printf(m, ",gid=%u", v9ses->gid);
	245	return 0;
	246	}
	247
322b329a EVH	248	static void
	249	v9fs_umount_begin(struct super_block *sb)
	250	{
	251	struct v9fs_session_info *v9ses = sb->s_fs_info;
	252
	253	v9fs_session_cancel(v9ses);
	254	}
	255
9e82cf6a EVH	256	static struct super_operations v9fs_super_ops = {
	257	.statfs = simple_statfs,
	258	.clear_inode = v9fs_clear_inode,
	259	.show_options = v9fs_show_options,
322b329a	260	.umount_begin = v9fs_umount_begin,
9e82cf6a EVH	261	};
	262
	263	struct file_system_type v9fs_fs_type = {
67543e50	264	.name = "9p",
9e82cf6a EVH	265	.get_sb = v9fs_get_sb,
	266	.kill_sb = v9fs_kill_super,
	267	.owner = THIS_MODULE,
	268	};