usb: storage: Add usb_stor_dbg, reduce object size

Reduce the size of the objects by consolidating
the duplicated USB_STORAGE into a single function.

Add function usb_stor_dbg to emit debugging messages.
Always validate the format and arguments.
Reduce the number of uses of CONFIG_USB_STORAGE_DEBUG.

Reduces size of objects ~7KB when CONFIG_USB_STORAGE_DEBUG
is set.

$ size drivers/usb/storage/built-in.o*
   text	   data	    bss	    dec	    hex	filename
 140133	  55296	  70312	 265741	  40e0d	drivers/usb/storage/built-in.o.new
 147494	  55248	  70296	 273038	  42a8e	drivers/usb/storage/built-in.o.old

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 19 insertions, 1 deletions

diff --git a/drivers/usb/storage/debug.c b/drivers/usb/storage/debug.c
index a2b5526c9fa..b428129526c 100644
--- a/drivers/usb/storage/debug.c
+++ b/drivers/usb/storage/debug.c
@@ -150,7 +150,7 @@ void usb_stor_show_command(struct scsi_cmnd *srb)
 	default: what = "(unknown command)"; break;
 	}
 	US_DEBUGP("Command %s (%d bytes)\n", what, srb->cmd_len);
-	US_DEBUGP("");
+	US_DEBUGP("bytes: ");
 	for (i = 0; i < srb->cmd_len && i < 16; i++)
 		US_DEBUGPX(" %02x", srb->cmnd[i]);
 	US_DEBUGPX("\n");
@@ -175,3 +175,21 @@ void usb_stor_show_sense(
 	US_DEBUGPX(what, ascq);
 	US_DEBUGPX("\n");
 }
+
+int usb_stor_dbg(const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+	int r;
+
+	va_start(args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	r = printk(KERN_DEBUG USB_STORAGE "%pV", &vaf);
+
+	va_end(args);
+
+	return r;
+}