pstore: pass reason to backend write callback

This allows a backend to filter on the dmesg reason as well as the pstore
reason. When ramoops is switched to pstore, this is needed since it has
no interest in storing non-crash dmesg details.

Drop pstore_write() as it has no users, and handling the "reason" here
has no obviously correct value.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/include/linux/pstore.h b/include/linux/pstore.h
index 2ca8cde..e1461e1 100644
--- a/include/linux/pstore.h
+++ b/include/linux/pstore.h
@@ -22,6 +22,9 @@
 #ifndef _LINUX_PSTORE_H
 #define _LINUX_PSTORE_H
 
+#include <linux/time.h>
+#include <linux/kmsg_dump.h>
+
 /* types */
 enum pstore_type_id {
 	PSTORE_TYPE_DMESG	= 0,
@@ -41,7 +44,8 @@
 	ssize_t		(*read)(u64 *id, enum pstore_type_id *type,
 			struct timespec *time, char **buf,
 			struct pstore_info *psi);
-	int		(*write)(enum pstore_type_id type, u64 *id,
+	int		(*write)(enum pstore_type_id type,
+			enum kmsg_dump_reason reason, u64 *id,
 			unsigned int part, size_t size, struct pstore_info *psi);
 	int		(*erase)(enum pstore_type_id type, u64 id,
 			struct pstore_info *psi);
@@ -50,18 +54,12 @@
 
 #ifdef CONFIG_PSTORE
 extern int pstore_register(struct pstore_info *);
-extern int pstore_write(enum pstore_type_id type, char *buf, size_t size);
 #else
 static inline int
 pstore_register(struct pstore_info *psi)
 {
 	return -ENODEV;
 }
-static inline int
-pstore_write(enum pstore_type_id type, char *buf, size_t size)
-{
-	return -ENODEV;
-}
 #endif
 
 #endif /*_LINUX_PSTORE_H*/