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/fs/pstore/platform.c b/fs/pstore/platform.c
index 57bbf90..f146d89 100644
--- a/fs/pstore/platform.c
+++ b/fs/pstore/platform.c
@@ -122,7 +122,7 @@
 		memcpy(dst, s1 + s1_start, l1_cpy);
 		memcpy(dst + l1_cpy, s2 + s2_start, l2_cpy);
 
-		ret = psinfo->write(PSTORE_TYPE_DMESG, &id, part,
+		ret = psinfo->write(PSTORE_TYPE_DMESG, reason, &id, part,
 				   hsize + l1_cpy + l2_cpy, psinfo);
 		if (ret == 0 && reason == KMSG_DUMP_OOPS && pstore_is_mounted())
 			pstore_new_entry = 1;
@@ -243,33 +243,5 @@
 	mod_timer(&pstore_timer, jiffies + PSTORE_INTERVAL);
 }
 
-/*
- * Call platform driver to write a record to the
- * persistent store.
- */
-int pstore_write(enum pstore_type_id type, char *buf, size_t size)
-{
-	u64		id;
-	int		ret;
-	unsigned long	flags;
-
-	if (!psinfo)
-		return -ENODEV;
-
-	if (size > psinfo->bufsize)
-		return -EFBIG;
-
-	spin_lock_irqsave(&psinfo->buf_lock, flags);
-	memcpy(psinfo->buf, buf, size);
-	ret = psinfo->write(type, &id, 0, size, psinfo);
-	if (ret == 0 && pstore_is_mounted())
-		pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf,
-			      size, CURRENT_TIME, psinfo);
-	spin_unlock_irqrestore(&psinfo->buf_lock, flags);
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(pstore_write);
-
 module_param(backend, charp, 0444);
 MODULE_PARM_DESC(backend, "Pstore backend to use");