include/linux/pstore.h

   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 */
  33 enum 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_UNKNOWN     = 255
  44 };
  45
  46 struct module;
  47
  48 struct pstore_info {
  49         struct module   *owner;
  50         char            *name;
  51         spinlock_t      buf_lock;       /* serialize access to 'buf' */
  52         char            *buf;
  53         size_t          bufsize;
  54         struct mutex    read_mutex;     /* serialize open/read/close */
  55         int             flags;
  56         int             (*open)(struct pstore_info *psi);
  57         int             (*close)(struct pstore_info *psi);
  58         ssize_t         (*read)(u64 *id, enum pstore_type_id *type,
  59                         int *count, struct timespec *time, char **buf,
  60                         bool *compressed, struct pstore_info *psi);
  61         int             (*write)(enum pstore_type_id type,
  62                         enum kmsg_dump_reason reason, u64 *id,
  63                         unsigned int part, int count, bool compressed,
  64                         size_t size, struct pstore_info *psi);
  65         int             (*write_buf)(enum pstore_type_id type,
  66                         enum kmsg_dump_reason reason, u64 *id,
  67                         unsigned int part, const char *buf, bool compressed,
  68                         size_t size, struct pstore_info *psi);
  69         int             (*erase)(enum pstore_type_id type, u64 id,
  70                         int count, struct timespec time,
  71                         struct pstore_info *psi);
  72         void            *data;
  73 };
  74
  75 #define PSTORE_FLAGS_FRAGILE    1
  76
  77 #ifdef CONFIG_PSTORE
  78 extern int pstore_register(struct pstore_info *);
  79 extern bool pstore_cannot_block_path(enum kmsg_dump_reason reason);
  80 #else
  81 static inline int
  82 pstore_register(struct pstore_info *psi)
  83 {
  84         return -ENODEV;
  85 }
  86 static inline bool
  87 pstore_cannot_block_path(enum kmsg_dump_reason reason)
  88 {
  89         return false;
  90 }
  91 #endif
  92
  93 #endif /*_LINUX_PSTORE_H*/