2 * Persistent Storage - pstore.h
4 * Copyright (C) 2010 Intel Corporation <tony.luck@intel.com>
6 * This code is the generic layer to export data records from platform
7 * level persistent storage via a file system.
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.
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.
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
22 #ifndef _LINUX_PSTORE_H
23 #define _LINUX_PSTORE_H
25 #include <linux/compiler.h>
26 #include <linux/errno.h>
27 #include <linux/kmsg_dump.h>
28 #include <linux/mutex.h>
29 #include <linux/spinlock.h>
30 #include <linux/time.h>
31 #include <linux/types.h>
35 PSTORE_TYPE_DMESG
= 0,
37 PSTORE_TYPE_CONSOLE
= 2,
38 PSTORE_TYPE_FTRACE
= 3,
39 /* PPC64 partition types */
40 PSTORE_TYPE_PPC_RTAS
= 4,
41 PSTORE_TYPE_PPC_OF
= 5,
42 PSTORE_TYPE_PPC_COMMON
= 6,
44 PSTORE_TYPE_PPC_OPAL
= 8,
45 PSTORE_TYPE_UNKNOWN
= 255
53 spinlock_t buf_lock
; /* serialize access to 'buf' */
56 struct mutex read_mutex
; /* serialize open/read/close */
58 int (*open
)(struct pstore_info
*psi
);
59 int (*close
)(struct pstore_info
*psi
);
60 ssize_t (*read
)(u64
*id
, enum pstore_type_id
*type
,
61 int *count
, struct timespec
*time
, char **buf
,
62 bool *compressed
, ssize_t
*ecc_notice_size
,
63 struct pstore_info
*psi
);
64 int (*write
)(enum pstore_type_id type
,
65 enum kmsg_dump_reason reason
, u64
*id
,
66 unsigned int part
, int count
, bool compressed
,
67 size_t size
, struct pstore_info
*psi
);
68 int (*write_buf
)(enum pstore_type_id type
,
69 enum kmsg_dump_reason reason
, u64
*id
,
70 unsigned int part
, const char *buf
, bool compressed
,
71 size_t size
, struct pstore_info
*psi
);
72 int (*write_buf_user
)(enum pstore_type_id type
,
73 enum kmsg_dump_reason reason
, u64
*id
,
74 unsigned int part
, const char __user
*buf
,
75 bool compressed
, size_t size
, struct pstore_info
*psi
);
76 int (*erase
)(enum pstore_type_id type
, u64 id
,
77 int count
, struct timespec time
,
78 struct pstore_info
*psi
);
82 #define PSTORE_FLAGS_DMESG (1 << 0)
83 #define PSTORE_FLAGS_FRAGILE PSTORE_FLAGS_DMESG
84 #define PSTORE_FLAGS_CONSOLE (1 << 1)
85 #define PSTORE_FLAGS_FTRACE (1 << 2)
86 #define PSTORE_FLAGS_PMSG (1 << 3)
88 extern int pstore_register(struct pstore_info
*);
89 extern void pstore_unregister(struct pstore_info
*);
90 extern bool pstore_cannot_block_path(enum kmsg_dump_reason reason
);
92 struct pstore_ftrace_record
{
94 unsigned long parent_ip
;
99 * ftrace related stuff: Both backends and frontends need these so expose
103 #if NR_CPUS <= 2 && defined(CONFIG_ARM_THUMB)
104 #define PSTORE_CPU_IN_IP 0x1
105 #elif NR_CPUS <= 4 && defined(CONFIG_ARM)
106 #define PSTORE_CPU_IN_IP 0x3
109 #define TS_CPU_SHIFT 8
110 #define TS_CPU_MASK (BIT(TS_CPU_SHIFT) - 1)
113 * If CPU number can be stored in IP, store it there, otherwise store it in
114 * the time stamp. This means more timestamp resolution is available when
115 * the CPU can be stored in the IP.
117 #ifdef PSTORE_CPU_IN_IP
119 pstore_ftrace_encode_cpu(struct pstore_ftrace_record
*rec
, unsigned int cpu
)
124 static inline unsigned int
125 pstore_ftrace_decode_cpu(struct pstore_ftrace_record
*rec
)
127 return rec
->ip
& PSTORE_CPU_IN_IP
;
131 pstore_ftrace_read_timestamp(struct pstore_ftrace_record
*rec
)
137 pstore_ftrace_write_timestamp(struct pstore_ftrace_record
*rec
, u64 val
)
143 pstore_ftrace_encode_cpu(struct pstore_ftrace_record
*rec
, unsigned int cpu
)
145 rec
->ts
&= ~(TS_CPU_MASK
);
149 static inline unsigned int
150 pstore_ftrace_decode_cpu(struct pstore_ftrace_record
*rec
)
152 return rec
->ts
& TS_CPU_MASK
;
156 pstore_ftrace_read_timestamp(struct pstore_ftrace_record
*rec
)
158 return rec
->ts
>> TS_CPU_SHIFT
;
162 pstore_ftrace_write_timestamp(struct pstore_ftrace_record
*rec
, u64 val
)
164 rec
->ts
= (rec
->ts
& TS_CPU_MASK
) | (val
<< TS_CPU_SHIFT
);
168 #endif /*_LINUX_PSTORE_H*/