USB: serial gadget: remove needless data structure

This removes a needless data structure from the serial gadget code;
it's a small code shrink, and a larger data shrink.

Since "struct usb_request" already has a "struct list_head" reserved
for use by gadget drivers, the serial gadget code doesn't need to
allocate wrapper structs to hold that list ... it can (and should!)
just use the list_head provided for that exact use.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Al Borchers <alborchers@steinerpoint.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/gadget/serial.c b/drivers/usb/gadget/serial.c
index 00da3f6..b0c32c7 100644 (file)
--- a/drivers/usb/gadget/serial.c
+++ b/drivers/usb/gadget/serial.c
@@ -121,12 +121,6 @@ struct gs_buf {
        char                    *buf_put;
 };
 
-/* list of requests */
-struct gs_req_entry {
-       struct list_head        re_entry;
-       struct usb_request      *re_req;
-};
-
 /* the port structure holds info for each port, one for each minor number */
 struct gs_port {
        struct gs_dev           *port_dev;      /* pointer to device struct */
@@ -185,10 +179,6 @@ static struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned int len,
        gfp_t kmalloc_flags);
 static void gs_free_req(struct usb_ep *ep, struct usb_request *req);
 
-static struct gs_req_entry *gs_alloc_req_entry(struct usb_ep *ep, unsigned len,
-       gfp_t kmalloc_flags);
-static void gs_free_req_entry(struct usb_ep *ep, struct gs_req_entry *req);
-
 static int gs_alloc_ports(struct gs_dev *dev, gfp_t kmalloc_flags);
 static void gs_free_ports(struct gs_dev *dev);
 
@@ -966,7 +956,6 @@ static int gs_send(struct gs_dev *dev)
        unsigned long flags;
        struct usb_ep *ep;
        struct usb_request *req;
-       struct gs_req_entry *req_entry;
 
        if (dev == NULL) {
                pr_err("gs_send: NULL device pointer\n");
@@ -979,10 +968,8 @@ static int gs_send(struct gs_dev *dev)
 
        while(!list_empty(&dev->dev_req_list)) {
 
-               req_entry = list_entry(dev->dev_req_list.next,
-                       struct gs_req_entry, re_entry);
-
-               req = req_entry->re_req;
+               req = list_entry(dev->dev_req_list.next,
+                               struct usb_request, list);
 
                len = gs_send_packet(dev, req->buf, ep->maxpacket);
 
@@ -992,7 +979,7 @@ static int gs_send(struct gs_dev *dev)
                                        *((unsigned char *)req->buf),
                                        *((unsigned char *)req->buf+1),
                                        *((unsigned char *)req->buf+2));
-                       list_del(&req_entry->re_entry);
+                       list_del(&req->list);
                        req->length = len;
                        spin_unlock_irqrestore(&dev->dev_lock, flags);
                        if ((ret=usb_ep_queue(ep, req, GFP_ATOMIC))) {
@@ -1175,7 +1162,6 @@ requeue:
 static void gs_write_complete(struct usb_ep *ep, struct usb_request *req)
 {
        struct gs_dev *dev = ep->driver_data;
-       struct gs_req_entry *gs_req = req->context;
 
        if (dev == NULL) {
                pr_err("gs_write_complete: NULL device pointer\n");
@@ -1186,13 +1172,8 @@ static void gs_write_complete(struct usb_ep *ep, struct usb_request *req)
        case 0:
                /* normal completion */
 requeue:
-               if (gs_req == NULL) {
-                       pr_err("gs_write_complete: NULL request pointer\n");
-                       return;
-               }
-
                spin_lock(&dev->dev_lock);
-               list_add(&gs_req->re_entry, &dev->dev_req_list);
+               list_add(&req->list, &dev->dev_req_list);
                spin_unlock(&dev->dev_lock);
 
                gs_send(dev);
@@ -1731,7 +1712,6 @@ static int gs_set_config(struct gs_dev *dev, unsigned config)
        struct usb_ep *ep;
        struct usb_endpoint_descriptor *ep_desc;
        struct usb_request *req;
-       struct gs_req_entry *req_entry;
 
        if (dev == NULL) {
                pr_err("gs_set_config: NULL device pointer\n");
@@ -1843,9 +1823,10 @@ static int gs_set_config(struct gs_dev *dev, unsigned config)
        /* allocate write requests, and put on free list */
        ep = dev->dev_in_ep;
        for (i=0; i<write_q_size; i++) {
-               if ((req_entry=gs_alloc_req_entry(ep, ep->maxpacket, GFP_ATOMIC))) {
-                       req_entry->re_req->complete = gs_write_complete;
-                       list_add(&req_entry->re_entry, &dev->dev_req_list);
+               req = gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC);
+               if (req) {
+                       req->complete = gs_write_complete;
+                       list_add(&req->list, &dev->dev_req_list);
                } else {
                        pr_err("gs_set_config: cannot allocate "
                                        "write requests\n");
@@ -1883,7 +1864,7 @@ exit_reset_config:
  */
 static void gs_reset_config(struct gs_dev *dev)
 {
-       struct gs_req_entry *req_entry;
+       struct usb_request *req;
 
        if (dev == NULL) {
                pr_err("gs_reset_config: NULL device pointer\n");
@@ -1897,10 +1878,10 @@ static void gs_reset_config(struct gs_dev *dev)
 
        /* free write requests on the free list */
        while(!list_empty(&dev->dev_req_list)) {
-               req_entry = list_entry(dev->dev_req_list.next,
-                       struct gs_req_entry, re_entry);
-               list_del(&req_entry->re_entry);
-               gs_free_req_entry(dev->dev_in_ep, req_entry);
+               req = list_entry(dev->dev_req_list.next,
+                               struct usb_request, list);
+               list_del(&req->list);
+               gs_free_req(dev->dev_in_ep, req);
        }
 
        /* disable endpoints, forcing completion of pending i/o; */
@@ -2009,46 +1990,6 @@ static void gs_free_req(struct usb_ep *ep, struct usb_request *req)
        }
 }
 
-/*
- * gs_alloc_req_entry
- *
- * Allocates a request and its buffer, using the given
- * endpoint, buffer len, and kmalloc flags.
- */
-static struct gs_req_entry *
-gs_alloc_req_entry(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags)
-{
-       struct gs_req_entry     *req;
-
-       req = kmalloc(sizeof(struct gs_req_entry), kmalloc_flags);
-       if (req == NULL)
-               return NULL;
-
-       req->re_req = gs_alloc_req(ep, len, kmalloc_flags);
-       if (req->re_req == NULL) {
-               kfree(req);
-               return NULL;
-       }
-
-       req->re_req->context = req;
-
-       return req;
-}
-
-/*
- * gs_free_req_entry
- *
- * Frees a request and its buffer.
- */
-static void gs_free_req_entry(struct usb_ep *ep, struct gs_req_entry *req)
-{
-       if (ep != NULL && req != NULL) {
-               if (req->re_req != NULL)
-                       gs_free_req(ep, req->re_req);
-               kfree(req);
-       }
-}
-
 /*
  * gs_alloc_ports
  *