1/*
2 * Persistent Storage - pstore.h
3 *
4 * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
5 *
6 * This code is the generic layer to export data records from platform
7 * level persistent storage via a file system.
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 as
11 *  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 the Free Software
20 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21 */
22#ifndef _LINUX_PSTORE_H
23#define _LINUX_PSTORE_H
24
25#include <linux/time.h>
26#include <linux/kmsg_dump.h>
27#include <linux/mutex.h>
28#include <linux/types.h>
29#include <linux/spinlock.h>
30#include <linux/errno.h>
31
32/* types */
33enum pstore_type_id {
34	PSTORE_TYPE_DMESG	= 0,
35	PSTORE_TYPE_MCE		= 1,
36	PSTORE_TYPE_CONSOLE	= 2,
37	PSTORE_TYPE_FTRACE	= 3,
38	/* PPC64 partition types */
39	PSTORE_TYPE_PPC_RTAS	= 4,
40	PSTORE_TYPE_PPC_OF	= 5,
41	PSTORE_TYPE_PPC_COMMON	= 6,
42	PSTORE_TYPE_PMSG	= 7,
43	PSTORE_TYPE_PPC_OPAL	= 8,
44	PSTORE_TYPE_UNKNOWN	= 255
45};
46
47struct module;
48
49struct pstore_info {
50	struct module	*owner;
51	char		*name;
52	spinlock_t	buf_lock;	/* serialize access to 'buf' */
53	char		*buf;
54	size_t		bufsize;
55	struct mutex	read_mutex;	/* serialize open/read/close */
56	int		flags;
57	int		(*open)(struct pstore_info *psi);
58	int		(*close)(struct pstore_info *psi);
59	ssize_t		(*read)(u64 *id, enum pstore_type_id *type,
60			int *count, struct timespec *time, char **buf,
61			bool *compressed, struct pstore_info *psi);
62	int		(*write)(enum pstore_type_id type,
63			enum kmsg_dump_reason reason, u64 *id,
64			unsigned int part, int count, bool compressed,
65			size_t size, struct pstore_info *psi);
66	int		(*write_buf)(enum pstore_type_id type,
67			enum kmsg_dump_reason reason, u64 *id,
68			unsigned int part, const char *buf, bool compressed,
69			size_t size, struct pstore_info *psi);
70	int		(*erase)(enum pstore_type_id type, u64 id,
71			int count, struct timespec time,
72			struct pstore_info *psi);
73	void		*data;
74};
75
76#define	PSTORE_FLAGS_FRAGILE	1
77
78#ifdef CONFIG_PSTORE
79extern int pstore_register(struct pstore_info *);
80extern bool pstore_cannot_block_path(enum kmsg_dump_reason reason);
81#else
82static inline int
83pstore_register(struct pstore_info *psi)
84{
85	return -ENODEV;
86}
87static inline bool
88pstore_cannot_block_path(enum kmsg_dump_reason reason)
89{
90	return false;
91}
92#endif
93
94#endif /*_LINUX_PSTORE_H*/
95