diff options
| -rw-r--r-- | include/linux/pstore.h | 133 |
1 files changed, 128 insertions, 5 deletions
diff --git a/include/linux/pstore.h b/include/linux/pstore.h index 0da29cae009b..56477ce6806a 100644 --- a/include/linux/pstore.h +++ b/include/linux/pstore.h @@ -30,7 +30,7 @@ #include <linux/time.h> #include <linux/types.h> -/* types */ +/* pstore record types (see fs/pstore/inode.c for filename templates) */ enum pstore_type_id { PSTORE_TYPE_DMESG = 0, PSTORE_TYPE_MCE = 1, @@ -47,14 +47,138 @@ enum pstore_type_id { struct module; +/** + * struct pstore_info - backend pstore driver structure + * + * @owner: module which is repsonsible for this backend driver + * @name: name of the backend driver + * + * @buf_lock: spinlock to serialize access to @buf + * @buf: preallocated crash dump buffer + * @bufsize: size of @buf available for crash dump writes + * + * @read_mutex: serializes @open, @read, @close, and @erase callbacks + * @flags: bitfield of frontends the backend can accept writes for + * @data: backend-private pointer passed back during callbacks + * + * Callbacks: + * + * @open: + * Notify backend that pstore is starting a full read of backend + * records. Followed by one or more @read calls, and a final @close. + * + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns 0 on success, and non-zero on error. + * + * @close: + * Notify backend that pstore has finished a full read of backend + * records. Always preceded by an @open call and one or more @read + * calls. + * + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns 0 on success, and non-zero on error. (Though pstore will + * ignore the error.) + * + * @read: + * Read next available backend record. Called after a successful + * @open. + * + * @id: out: unique identifier for the record + * @type: out: pstore record type + * @count: out: for PSTORE_TYPE_DMESG, the Oops count. + * @time: out: timestamp for the record + * @buf: out: kmalloc copy of record contents, to be freed by pstore + * @compressed: + * out: if the record contents are compressed + * @ecc_notice_size: + * out: ECC information + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns record size on success, zero when no more records are + * available, or negative on error. + * + * @write: + * Perform a frontend notification of a write to a backend record. The + * data to be stored has already been written to the registered @buf + * of the @psi structure. + * + * @type: in: pstore record type to write + * @reason: + * in: pstore write reason + * @id: out: unique identifier for the record + * @part: in: position in a multipart write + * @count: in: increasing from 0 since boot, the number of this Oops + * @compressed: + * in: if the record is compressed + * @size: in: size of the write + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns 0 on success, and non-zero on error. + * + * @write_buf: + * Perform a frontend write to a backend record, using a specified + * buffer. Unlike @write, this does not use the @psi @buf. + * + * @type: in: pstore record type to write + * @reason: + * in: pstore write reason + * @id: out: unique identifier for the record + * @part: in: position in a multipart write + * @buf: in: pointer to contents to write to backend record + * @compressed: + * in: if the record is compressed + * @size: in: size of the write + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns 0 on success, and non-zero on error. + * + * @write_buf_user: + * Perform a frontend write to a backend record, using a specified + * buffer that is coming directly from userspace. + * + * @type: in: pstore record type to write + * @reason: + * in: pstore write reason + * @id: out: unique identifier for the record + * @part: in: position in a multipart write + * @buf: in: pointer to userspace contents to write to backend record + * @compressed: + * in: if the record is compressed + * @size: in: size of the write + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns 0 on success, and non-zero on error. + * + * @erase: + * Delete a record from backend storage. Different backends + * identify records differently, so all possible methods of + * identification are included to help the backend locate the + * record to remove. + * + * @type: in: pstore record type to write + * @id: in: per-type unique identifier for the record + * @count: in: Oops count + * @time: in: timestamp for the record + * @psi: in: pointer to the struct pstore_info for the backend + * + * Returns 0 on success, and non-zero on error. + * + */ struct pstore_info { struct module *owner; char *name; - spinlock_t buf_lock; /* serialize access to 'buf' */ + + spinlock_t buf_lock; char *buf; size_t bufsize; - struct mutex read_mutex; /* serialize open/read/close */ + + struct mutex read_mutex; + int flags; + void *data; + int (*open)(struct pstore_info *psi); int (*close)(struct pstore_info *psi); ssize_t (*read)(u64 *id, enum pstore_type_id *type, @@ -76,11 +200,10 @@ struct pstore_info { int (*erase)(enum pstore_type_id type, u64 id, int count, struct timespec time, struct pstore_info *psi); - void *data; }; +/* Supported frontends */ #define PSTORE_FLAGS_DMESG (1 << 0) -#define PSTORE_FLAGS_FRAGILE PSTORE_FLAGS_DMESG #define PSTORE_FLAGS_CONSOLE (1 << 1) #define PSTORE_FLAGS_FTRACE (1 << 2) #define PSTORE_FLAGS_PMSG (1 << 3) |