[mirror_ubuntu-artful-kernel.git] / fs / pstore / inode.c

/*
 * Persistent Storage - ramfs parts.
 *
 * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
 *
 *  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 the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/fsnotify.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/string.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/ramfs.h>
#include <linux/parser.h>
#include <linux/sched.h>
#include <linux/magic.h>
#include <linux/pstore.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>

#include "internal.h"

#define	PSTORE_NAMELEN	64

static DEFINE_SPINLOCK(allpstore_lock);
static LIST_HEAD(allpstore);

struct pstore_private {
	struct list_head list;
	struct pstore_info *psi;
	enum pstore_type_id type;
	u64	id;
	ssize_t	size;
	char	data[];
};

struct pstore_ftrace_seq_data {
	const void *ptr;
	size_t off;
	size_t size;
};

#define REC_SIZE sizeof(struct pstore_ftrace_record)

static void *pstore_ftrace_seq_start(struct seq_file *s, loff_t *pos)
{
	struct pstore_private *ps = s->private;
	struct pstore_ftrace_seq_data *data;

	data = kzalloc(sizeof(*data), GFP_KERNEL);
	if (!data)
		return NULL;

	data->off = ps->size % REC_SIZE;
	data->off += *pos * REC_SIZE;
	if (data->off + REC_SIZE > ps->size) {
		kfree(data);
		return NULL;
	}

	return data;

}

static void pstore_ftrace_seq_stop(struct seq_file *s, void *v)
{
	kfree(v);
}

static void *pstore_ftrace_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
	struct pstore_private *ps = s->private;
	struct pstore_ftrace_seq_data *data = v;

	data->off += REC_SIZE;
	if (data->off + REC_SIZE > ps->size)
		return NULL;

	(*pos)++;
	return data;
}

static int pstore_ftrace_seq_show(struct seq_file *s, void *v)
{
	struct pstore_private *ps = s->private;
	struct pstore_ftrace_seq_data *data = v;
	struct pstore_ftrace_record *rec = (void *)(ps->data + data->off);

	seq_printf(s, "%d %08lx  %08lx  %pf <- %pF\n",
		pstore_ftrace_decode_cpu(rec), rec->ip, rec->parent_ip,
		(void *)rec->ip, (void *)rec->parent_ip);

	return 0;
}

static const struct seq_operations pstore_ftrace_seq_ops = {
	.start	= pstore_ftrace_seq_start,
	.next	= pstore_ftrace_seq_next,
	.stop	= pstore_ftrace_seq_stop,
	.show	= pstore_ftrace_seq_show,
};

static ssize_t pstore_file_read(struct file *file, char __user *userbuf,
						size_t count, loff_t *ppos)
{
	struct seq_file *sf = file->private_data;
	struct pstore_private *ps = sf->private;

	if (ps->type == PSTORE_TYPE_FTRACE)
		return seq_read(file, userbuf, count, ppos);
	return simple_read_from_buffer(userbuf, count, ppos, ps->data, ps->size);
}

static int pstore_file_open(struct inode *inode, struct file *file)
{
	struct pstore_private *ps = inode->i_private;
	struct seq_file *sf;
	int err;
	const struct seq_operations *sops = NULL;

	if (ps->type == PSTORE_TYPE_FTRACE)
		sops = &pstore_ftrace_seq_ops;

	err = seq_open(file, sops);
	if (err < 0)
		return err;

	sf = file->private_data;
	sf->private = ps;

	return 0;
}

static loff_t pstore_file_llseek(struct file *file, loff_t off, int origin)
{
	struct seq_file *sf = file->private_data;

	if (sf->op)
		return seq_lseek(file, off, origin);
	return default_llseek(file, off, origin);
}

static const struct file_operations pstore_file_operations = {
	.open		= pstore_file_open,
	.read		= pstore_file_read,
	.llseek		= pstore_file_llseek,
	.release	= seq_release,
};

/*
 * When a file is unlinked from our file system we call the
 * platform driver to erase the record from persistent store.
 */
static int pstore_unlink(struct inode *dir, struct dentry *dentry)
{
	struct pstore_private *p = dentry->d_inode->i_private;

	if (p->psi->erase)
		p->psi->erase(p->type, p->id, dentry->d_inode->i_ctime,
			      p->psi);

	return simple_unlink(dir, dentry);
}

static void pstore_evict_inode(struct inode *inode)
{
	struct pstore_private	*p = inode->i_private;
	unsigned long		flags;

	clear_inode(inode);
	if (p) {
		spin_lock_irqsave(&allpstore_lock, flags);
		list_del(&p->list);
		spin_unlock_irqrestore(&allpstore_lock, flags);
		kfree(p);
	}
}

static const struct inode_operations pstore_dir_inode_operations = {
	.lookup		= simple_lookup,
	.unlink		= pstore_unlink,
};

static struct inode *pstore_get_inode(struct super_block *sb)
{
	struct inode *inode = new_inode(sb);
	if (inode) {
		inode->i_ino = get_next_ino();
		inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
	}
	return inode;
}

enum {
	Opt_kmsg_bytes, Opt_err
};

static const match_table_t tokens = {
	{Opt_kmsg_bytes, "kmsg_bytes=%u"},
	{Opt_err, NULL}
};

static void parse_options(char *options)
{
	char		*p;
	substring_t	args[MAX_OPT_ARGS];
	int		option;

	if (!options)
		return;

	while ((p = strsep(&options, ",")) != NULL) {
		int token;

		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token) {
		case Opt_kmsg_bytes:
			if (!match_int(&args[0], &option))
				pstore_set_kmsg_bytes(option);
			break;
		}
	}
}

static int pstore_remount(struct super_block *sb, int *flags, char *data)
{
	parse_options(data);

	return 0;
}

static const struct super_operations pstore_ops = {
	.statfs		= simple_statfs,
	.drop_inode	= generic_delete_inode,
	.evict_inode	= pstore_evict_inode,
	.remount_fs	= pstore_remount,
	.show_options	= generic_show_options,
};

static struct super_block *pstore_sb;

int pstore_is_mounted(void)
{
	return pstore_sb != NULL;
}

/*
 * Make a regular file in the root directory of our file system.
 * Load it up with "size" bytes of data from "buf".
 * Set the mtime & ctime to the date that this record was originally stored.
 */
int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id,
		  char *data, size_t size, struct timespec time,
		  struct pstore_info *psi)
{
	struct dentry		*root = pstore_sb->s_root;
	struct dentry		*dentry;
	struct inode		*inode;
	int			rc = 0;
	char			name[PSTORE_NAMELEN];
	struct pstore_private	*private, *pos;
	unsigned long		flags;

	spin_lock_irqsave(&allpstore_lock, flags);
	list_for_each_entry(pos, &allpstore, list) {
		if (pos->type == type &&
		    pos->id == id &&
		    pos->psi == psi) {
			rc = -EEXIST;
			break;
		}
	}
	spin_unlock_irqrestore(&allpstore_lock, flags);
	if (rc)
		return rc;

	rc = -ENOMEM;
	inode = pstore_get_inode(pstore_sb);
	if (!inode)
		goto fail;
	inode->i_mode = S_IFREG | 0444;
	inode->i_fop = &pstore_file_operations;
	private = kmalloc(sizeof *private + size, GFP_KERNEL);
	if (!private)
		goto fail_alloc;
	private->type = type;
	private->id = id;
	private->psi = psi;

	switch (type) {
	case PSTORE_TYPE_DMESG:
		sprintf(name, "dmesg-%s-%lld", psname, id);
		break;
	case PSTORE_TYPE_CONSOLE:
		sprintf(name, "console-%s", psname);
		break;
	case PSTORE_TYPE_FTRACE:
		sprintf(name, "ftrace-%s", psname);
		break;
	case PSTORE_TYPE_MCE:
		sprintf(name, "mce-%s-%lld", psname, id);
		break;
	case PSTORE_TYPE_UNKNOWN:
		sprintf(name, "unknown-%s-%lld", psname, id);
		break;
	default:
		sprintf(name, "type%d-%s-%lld", type, psname, id);
		break;
	}

	mutex_lock(&root->d_inode->i_mutex);

	rc = -ENOSPC;
	dentry = d_alloc_name(root, name);
	if (IS_ERR(dentry))
		goto fail_lockedalloc;

	memcpy(private->data, data, size);
	inode->i_size = private->size = size;

	inode->i_private = private;

	if (time.tv_sec)
		inode->i_mtime = inode->i_ctime = time;

	d_add(dentry, inode);

	spin_lock_irqsave(&allpstore_lock, flags);
	list_add(&private->list, &allpstore);
	spin_unlock_irqrestore(&allpstore_lock, flags);

	mutex_unlock(&root->d_inode->i_mutex);

	return 0;

fail_lockedalloc:
	mutex_unlock(&root->d_inode->i_mutex);
	kfree(private);
fail_alloc:
	iput(inode);

fail:
	return rc;
}

static int pstore_fill_super(struct super_block *sb, void *data, int silent)
{
	struct inode *inode;

	save_mount_options(sb, data);

	pstore_sb = sb;

	sb->s_maxbytes		= MAX_LFS_FILESIZE;
	sb->s_blocksize		= PAGE_CACHE_SIZE;
	sb->s_blocksize_bits	= PAGE_CACHE_SHIFT;
	sb->s_magic		= PSTOREFS_MAGIC;
	sb->s_op		= &pstore_ops;
	sb->s_time_gran		= 1;

	parse_options(data);

	inode = pstore_get_inode(sb);
	if (inode) {
		inode->i_mode = S_IFDIR | 0755;
		inode->i_op = &pstore_dir_inode_operations;
		inode->i_fop = &simple_dir_operations;
		inc_nlink(inode);
	}
	sb->s_root = d_make_root(inode);
	if (!sb->s_root)
		return -ENOMEM;

	pstore_get_records(0);

	return 0;
}

static struct dentry *pstore_mount(struct file_system_type *fs_type,
	int flags, const char *dev_name, void *data)
{
	return mount_single(fs_type, flags, data, pstore_fill_super);
}

static void pstore_kill_sb(struct super_block *sb)
{
	kill_litter_super(sb);
	pstore_sb = NULL;
}

static struct file_system_type pstore_fs_type = {
	.name		= "pstore",
	.mount		= pstore_mount,
	.kill_sb	= pstore_kill_sb,
};

static int __init init_pstore_fs(void)
{
	return register_filesystem(&pstore_fs_type);
}
module_init(init_pstore_fs)

MODULE_AUTHOR("Tony Luck <tony.luck@intel.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
ca01d6dd TL	1	/*
	2	* Persistent Storage - ramfs parts.
	3	*
	4	* Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	18	*/
	19
	20	#include <linux/module.h>
	21	#include <linux/fs.h>
	22	#include <linux/fsnotify.h>
	23	#include <linux/pagemap.h>
	24	#include <linux/highmem.h>
	25	#include <linux/time.h>
	26	#include <linux/init.h>
6dda9266	27	#include <linux/list.h>
ca01d6dd TL	28	#include <linux/string.h>
ca01d6dd TL	29	#include <linux/mount.h>
060287b8	30	#include <linux/seq_file.h>
ca01d6dd	31	#include <linux/ramfs.h>
366f7e7a	32	#include <linux/parser.h>
ca01d6dd TL	33	#include <linux/sched.h>
	34	#include <linux/magic.h>
	35	#include <linux/pstore.h>
	36	#include <linux/slab.h>
6dda9266	37	#include <linux/spinlock.h>
ca01d6dd TL	38	#include <linux/uaccess.h>
	39
	40	#include "internal.h"
	41
	42	#define PSTORE_NAMELEN 64
	43
6dda9266 TL	44	static DEFINE_SPINLOCK(allpstore_lock);
	45	static LIST_HEAD(allpstore);
	46
ca01d6dd	47	struct pstore_private {
6dda9266	48	struct list_head list;
638c1fd3	49	struct pstore_info *psi;
56280682 MG	50	enum pstore_type_id type;
56280682 MG	51	u64 id;
fbe0aa1f TL	52	ssize_t size;
fbe0aa1f TL	53	char data[];
ca01d6dd TL	54	};
ca01d6dd TL	55
060287b8 AV	56	struct pstore_ftrace_seq_data {
	57	const void *ptr;
	58	size_t off;
	59	size_t size;
	60	};
	61
	62	#define REC_SIZE sizeof(struct pstore_ftrace_record)
	63
	64	static void pstore_ftrace_seq_start(struct seq_file s, loff_t *pos)
	65	{
	66	struct pstore_private *ps = s->private;
	67	struct pstore_ftrace_seq_data *data;
	68
	69	data = kzalloc(sizeof(*data), GFP_KERNEL);
	70	if (!data)
	71	return NULL;
	72
	73	data->off = ps->size % REC_SIZE;
	74	data->off += pos REC_SIZE;
	75	if (data->off + REC_SIZE > ps->size) {
	76	kfree(data);
	77	return NULL;
	78	}
	79
	80	return data;
	81
	82	}
	83
	84	static void pstore_ftrace_seq_stop(struct seq_file s, void v)
	85	{
	86	kfree(v);
	87	}
	88
	89	static void pstore_ftrace_seq_next(struct seq_file s, void v, loff_t pos)
	90	{
	91	struct pstore_private *ps = s->private;
	92	struct pstore_ftrace_seq_data *data = v;
	93
	94	data->off += REC_SIZE;
	95	if (data->off + REC_SIZE > ps->size)
	96	return NULL;
	97
	98	(*pos)++;
	99	return data;
	100	}
	101
	102	static int pstore_ftrace_seq_show(struct seq_file s, void v)
	103	{
	104	struct pstore_private *ps = s->private;
	105	struct pstore_ftrace_seq_data *data = v;
	106	struct pstore_ftrace_record rec = (void )(ps->data + data->off);
	107
	108	seq_printf(s, "%d %08lx %08lx %pf <- %pF\n",
	109	pstore_ftrace_decode_cpu(rec), rec->ip, rec->parent_ip,
	110	(void )rec->ip, (void )rec->parent_ip);
	111
	112	return 0;
	113	}
	114
	115	static const struct seq_operations pstore_ftrace_seq_ops = {
	116	.start = pstore_ftrace_seq_start,
	117	.next = pstore_ftrace_seq_next,
	118	.stop = pstore_ftrace_seq_stop,
	119	.show = pstore_ftrace_seq_show,
120	};
121
fbe0aa1f TL	122	static ssize_t pstore_file_read(struct file file, char __user userbuf,
	123	size_t count, loff_t *ppos)
	124	{
060287b8 AV	125	struct seq_file *sf = file->private_data;
060287b8 AV	126	struct pstore_private *ps = sf->private;
fbe0aa1f	127
060287b8 AV	128	if (ps->type == PSTORE_TYPE_FTRACE)
060287b8 AV	129	return seq_read(file, userbuf, count, ppos);
fbe0aa1f TL	130	return simple_read_from_buffer(userbuf, count, ppos, ps->data, ps->size);
	131	}
	132
060287b8 AV	133	static int pstore_file_open(struct inode inode, struct file file)
	134	{
	135	struct pstore_private *ps = inode->i_private;
	136	struct seq_file *sf;
	137	int err;
	138	const struct seq_operations *sops = NULL;
	139
	140	if (ps->type == PSTORE_TYPE_FTRACE)
	141	sops = &pstore_ftrace_seq_ops;
	142
	143	err = seq_open(file, sops);
	144	if (err < 0)
	145	return err;
	146
	147	sf = file->private_data;
	148	sf->private = ps;
	149
	150	return 0;
	151	}
	152
	153	static loff_t pstore_file_llseek(struct file *file, loff_t off, int origin)
	154	{
	155	struct seq_file *sf = file->private_data;
	156
	157	if (sf->op)
	158	return seq_lseek(file, off, origin);
	159	return default_llseek(file, off, origin);
	160	}
	161
fbe0aa1f	162	static const struct file_operations pstore_file_operations = {
060287b8 AV	163	.open = pstore_file_open,
	164	.read = pstore_file_read,
	165	.llseek = pstore_file_llseek,
	166	.release = seq_release,
fbe0aa1f	167	};
ca01d6dd TL	168
	169	/*
	170	* When a file is unlinked from our file system we call the
	171	* platform driver to erase the record from persistent store.
	172	*/
	173	static int pstore_unlink(struct inode dir, struct dentry dentry)
	174	{
	175	struct pstore_private *p = dentry->d_inode->i_private;
	176
2174f6df	177	if (p->psi->erase)
a9efd39c SA	178	p->psi->erase(p->type, p->id, dentry->d_inode->i_ctime,
a9efd39c SA	179	p->psi);
ca01d6dd TL	180
	181	return simple_unlink(dir, dentry);
	182	}
	183
a872d510 TL	184	static void pstore_evict_inode(struct inode *inode)
a872d510 TL	185	{
6dda9266 TL	186	struct pstore_private *p = inode->i_private;
	187	unsigned long flags;
	188
dbd5768f	189	clear_inode(inode);
6dda9266 TL	190	if (p) {
	191	spin_lock_irqsave(&allpstore_lock, flags);
	192	list_del(&p->list);
	193	spin_unlock_irqrestore(&allpstore_lock, flags);
	194	kfree(p);
	195	}
a872d510 TL	196	}
a872d510 TL	197
ca01d6dd TL	198	static const struct inode_operations pstore_dir_inode_operations = {
	199	.lookup = simple_lookup,
	200	.unlink = pstore_unlink,
	201	};
	202
22a71c30	203	static struct inode pstore_get_inode(struct super_block sb)
fbe0aa1f TL	204	{
fbe0aa1f TL	205	struct inode *inode = new_inode(sb);
fbe0aa1f TL	206	if (inode) {
fbe0aa1f TL	207	inode->i_ino = get_next_ino();
fbe0aa1f	208	inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
fbe0aa1f TL	209	}
	210	return inode;
	211	}
	212
366f7e7a TL	213	enum {
	214	Opt_kmsg_bytes, Opt_err
	215	};
	216
	217	static const match_table_t tokens = {
	218	{Opt_kmsg_bytes, "kmsg_bytes=%u"},
	219	{Opt_err, NULL}
	220	};
	221
	222	static void parse_options(char *options)
	223	{
	224	char *p;
	225	substring_t args[MAX_OPT_ARGS];
	226	int option;
	227
	228	if (!options)
	229	return;
	230
	231	while ((p = strsep(&options, ",")) != NULL) {
	232	int token;
	233
	234	if (!*p)
	235	continue;
	236
	237	token = match_token(p, tokens, args);
	238	switch (token) {
	239	case Opt_kmsg_bytes:
	240	if (!match_int(&args[0], &option))
	241	pstore_set_kmsg_bytes(option);
	242	break;
	243	}
	244	}
	245	}
	246
	247	static int pstore_remount(struct super_block sb, int flags, char *data)
	248	{
	249	parse_options(data);
	250
	251	return 0;
	252	}
	253
ca01d6dd TL	254	static const struct super_operations pstore_ops = {
	255	.statfs = simple_statfs,
	256	.drop_inode = generic_delete_inode,
a872d510	257	.evict_inode = pstore_evict_inode,
366f7e7a	258	.remount_fs = pstore_remount,
ca01d6dd TL	259	.show_options = generic_show_options,
	260	};
	261
	262	static struct super_block *pstore_sb;
ca01d6dd TL	263
	264	int pstore_is_mounted(void)
	265	{
fbe0aa1f	266	return pstore_sb != NULL;
ca01d6dd TL	267	}
	268
	269	/*
	270	* Make a regular file in the root directory of our file system.
	271	* Load it up with "size" bytes of data from "buf".
	272	* Set the mtime & ctime to the date that this record was originally stored.
	273	*/
	274	int pstore_mkfile(enum pstore_type_id type, char *psname, u64 id,
638c1fd3 MG	275	char *data, size_t size, struct timespec time,
638c1fd3 MG	276	struct pstore_info *psi)
ca01d6dd TL	277	{
	278	struct dentry *root = pstore_sb->s_root;
	279	struct dentry *dentry;
	280	struct inode *inode;
6dda9266	281	int rc = 0;
ca01d6dd	282	char name[PSTORE_NAMELEN];
6dda9266 TL	283	struct pstore_private private, pos;
	284	unsigned long flags;
	285
	286	spin_lock_irqsave(&allpstore_lock, flags);
	287	list_for_each_entry(pos, &allpstore, list) {
	288	if (pos->type == type &&
	289	pos->id == id &&
	290	pos->psi == psi) {
	291	rc = -EEXIST;
	292	break;
	293	}
	294	}
	295	spin_unlock_irqrestore(&allpstore_lock, flags);
	296	if (rc)
	297	return rc;
ca01d6dd TL	298
ca01d6dd TL	299	rc = -ENOMEM;
22a71c30	300	inode = pstore_get_inode(pstore_sb);
ca01d6dd TL	301	if (!inode)
ca01d6dd TL	302	goto fail;
22a71c30 AV	303	inode->i_mode = S_IFREG \| 0444;
22a71c30 AV	304	inode->i_fop = &pstore_file_operations;
fbe0aa1f	305	private = kmalloc(sizeof *private + size, GFP_KERNEL);
ca01d6dd TL	306	if (!private)
ca01d6dd TL	307	goto fail_alloc;
56280682	308	private->type = type;
ca01d6dd	309	private->id = id;
638c1fd3	310	private->psi = psi;
ca01d6dd TL	311
	312	switch (type) {
	313	case PSTORE_TYPE_DMESG:
	314	sprintf(name, "dmesg-%s-%lld", psname, id);
	315	break;
f29e5956 AV	316	case PSTORE_TYPE_CONSOLE:
	317	sprintf(name, "console-%s", psname);
	318	break;
060287b8 AV	319	case PSTORE_TYPE_FTRACE:
	320	sprintf(name, "ftrace-%s", psname);
	321	break;
ca01d6dd TL	322	case PSTORE_TYPE_MCE:
	323	sprintf(name, "mce-%s-%lld", psname, id);
	324	break;
	325	case PSTORE_TYPE_UNKNOWN:
	326	sprintf(name, "unknown-%s-%lld", psname, id);
	327	break;
	328	default:
	329	sprintf(name, "type%d-%s-%lld", type, psname, id);
	330	break;
	331	}
	332
	333	mutex_lock(&root->d_inode->i_mutex);
	334
	335	rc = -ENOSPC;
	336	dentry = d_alloc_name(root, name);
	337	if (IS_ERR(dentry))
	338	goto fail_lockedalloc;
	339
fbe0aa1f TL	340	memcpy(private->data, data, size);
fbe0aa1f TL	341	inode->i_size = private->size = size;
ca01d6dd TL	342
	343	inode->i_private = private;
	344
	345	if (time.tv_sec)
	346	inode->i_mtime = inode->i_ctime = time;
	347
fbe0aa1f	348	d_add(dentry, inode);
ca01d6dd	349
6dda9266 TL	350	spin_lock_irqsave(&allpstore_lock, flags);
	351	list_add(&private->list, &allpstore);
	352	spin_unlock_irqrestore(&allpstore_lock, flags);
	353
ca01d6dd	354	mutex_unlock(&root->d_inode->i_mutex);
fbe0aa1f TL	355
fbe0aa1f TL	356	return 0;
ca01d6dd TL	357
	358	fail_lockedalloc:
	359	mutex_unlock(&root->d_inode->i_mutex);
	360	kfree(private);
	361	fail_alloc:
	362	iput(inode);
	363
	364	fail:
	365	return rc;
	366	}
	367
364ed2f4	368	static int pstore_fill_super(struct super_block sb, void data, int silent)
ca01d6dd	369	{
318ceed0	370	struct inode *inode;
ca01d6dd TL	371
	372	save_mount_options(sb, data);
	373
	374	pstore_sb = sb;
	375
	376	sb->s_maxbytes = MAX_LFS_FILESIZE;
	377	sb->s_blocksize = PAGE_CACHE_SIZE;
	378	sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
	379	sb->s_magic = PSTOREFS_MAGIC;
	380	sb->s_op = &pstore_ops;
	381	sb->s_time_gran = 1;
	382
366f7e7a TL	383	parse_options(data);
366f7e7a TL	384
22a71c30	385	inode = pstore_get_inode(sb);
318ceed0	386	if (inode) {
22a71c30	387	inode->i_mode = S_IFDIR \| 0755;
318ceed0	388	inode->i_op = &pstore_dir_inode_operations;
22a71c30 AV	389	inode->i_fop = &simple_dir_operations;
22a71c30 AV	390	inc_nlink(inode);
ca01d6dd	391	}
318ceed0 AV	392	sb->s_root = d_make_root(inode);
	393	if (!sb->s_root)
	394	return -ENOMEM;
ca01d6dd	395
6dda9266	396	pstore_get_records(0);
ca01d6dd TL	397
ca01d6dd TL	398	return 0;
ca01d6dd TL	399	}
ca01d6dd TL	400
fbe0aa1f TL	401	static struct dentry pstore_mount(struct file_system_type fs_type,
fbe0aa1f TL	402	int flags, const char dev_name, void data)
ca01d6dd	403	{
fbe0aa1f	404	return mount_single(fs_type, flags, data, pstore_fill_super);
ca01d6dd TL	405	}
	406
	407	static void pstore_kill_sb(struct super_block *sb)
	408	{
	409	kill_litter_super(sb);
	410	pstore_sb = NULL;
ca01d6dd TL	411	}
	412
	413	static struct file_system_type pstore_fs_type = {
	414	.name = "pstore",
fbe0aa1f	415	.mount = pstore_mount,
ca01d6dd TL	416	.kill_sb = pstore_kill_sb,
	417	};
	418
	419	static int __init init_pstore_fs(void)
	420	{
366f7e7a	421	return register_filesystem(&pstore_fs_type);
ca01d6dd TL	422	}
	423	module_init(init_pstore_fs)
	424
	425	MODULE_AUTHOR("Tony Luck <tony.luck@intel.com>");
	426	MODULE_LICENSE("GPL");