USB: Sane memory allocation in option driver

The option driver
- violates DMA coherency rules
- allocates ~16500 bytes in one chunk
This patch splits out the buffers and uses __get_free_page() to avoid
higher order allocations.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Acked-By: Matthias Urlichs <matthias@urlichs.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index 5e8bf1bc1e50577fb6231e8088b63fdda307994c..a8126988efe6b2f5acc42950a2dff4c085cf2d48 100644 (file)
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -247,10 +247,10 @@ static int debug;
 struct option_port_private {
        /* Input endpoints and buffer for this port */
        struct urb *in_urbs[N_IN_URB];
-       char in_buffer[N_IN_URB][IN_BUFLEN];
+       u8 *in_buffer[N_IN_URB];
        /* Output endpoints and buffer for this port */
        struct urb *out_urbs[N_OUT_URB];
-       char out_buffer[N_OUT_URB][OUT_BUFLEN];
+       u8 *out_buffer[N_OUT_URB];
        unsigned long out_busy;         /* Bit vector of URBs in use */
 
        /* Settings for the port */
@@ -737,9 +737,10 @@ static int option_send_setup(struct usb_serial_port *port)
 
 static int option_startup(struct usb_serial *serial)
 {
-       int i, err;
+       int i, j, err;
        struct usb_serial_port *port;
        struct option_port_private *portdata;
+       u8 *buffer;
 
        dbg("%s", __FUNCTION__);
 
@@ -753,6 +754,20 @@ static int option_startup(struct usb_serial *serial)
                        return (1);
                }
 
+               for (j = 0; j < N_IN_URB; j++) {
+                       buffer = (u8 *)__get_free_page(GFP_KERNEL);
+                       if (!buffer)
+                               goto bail_out_error;
+                       portdata->in_buffer[j] = buffer;
+               }
+
+               for (j = 0; j < N_OUT_URB; j++) {
+                       buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
+                       if (!buffer)
+                               goto bail_out_error2;
+                       portdata->out_buffer[j] = buffer;
+               }
+
                usb_set_serial_port_data(port, portdata);
 
                if (! port->interrupt_in_urb)
@@ -766,6 +781,16 @@ static int option_startup(struct usb_serial *serial)
        option_setup_urbs(serial);
 
        return (0);
+
+bail_out_error2:
+       for (j = 0; j < N_OUT_URB; j++)
+               kfree(portdata->out_buffer[j]);
+bail_out_error:
+       for (j = 0; j < N_IN_URB; j++)
+               if (portdata->in_buffer[j])
+                       free_page((unsigned long)portdata->in_buffer[j]);
+       kfree(portdata);
+       return 1;
 }
 
 static void option_shutdown(struct usb_serial *serial)
@@ -794,12 +819,14 @@ static void option_shutdown(struct usb_serial *serial)
                for (j = 0; j < N_IN_URB; j++) {
                        if (portdata->in_urbs[j]) {
                                usb_free_urb(portdata->in_urbs[j]);
+                               free_page((unsigned long)portdata->in_buffer[j]);
                                portdata->in_urbs[j] = NULL;
                        }
                }
                for (j = 0; j < N_OUT_URB; j++) {
                        if (portdata->out_urbs[j]) {
                                usb_free_urb(portdata->out_urbs[j]);
+                               kfree(portdata->out_buffer[j]);
                                portdata->out_urbs[j] = NULL;
                        }
                }