scsi: saner replacements for ->proc_info()

It's still an obsolete interface; don't introduce those in new drivers.
However, it's saner than the ->proc_info() and commits after this one
will convert the existing ->proc_info() users to it.

The read side is ->show_info(seq_file *, struct Scsi_Host *); use
seq_... for generating contents.

The write side is ->write_info(struct Scsi_Host *, char *, int).

Again, this is driven by procfs needs; we are going to kill ->write_proc()
and ->read_proc() and this is the main obstacle to burying that piece of
shit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index 2b6956e..70e08e4 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -6,6 +6,7 @@
 #include <linux/types.h>
 #include <linux/workqueue.h>
 #include <linux/mutex.h>
+#include <linux/seq_file.h>
 #include <scsi/scsi.h>
 
 struct request_queue;
@@ -341,6 +342,8 @@
 	 * Status: OBSOLETE
 	 */
 	int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
+	int (*show_info)(struct seq_file *, struct Scsi_Host *);
+	int (*write_info)(struct Scsi_Host *, char *, int);
 
 	/*
 	 * This is an optional routine that allows the transport to become
@@ -375,7 +378,7 @@
 
 	/*
 	 * Used to store the procfs directory if a driver implements the
-	 * proc_info method.
+	 * proc_info or show_info method.
 	 */
 	struct proc_dir_entry *proc_dir;