[PATCH] TTY layer buffering revamp

[mirror_ubuntu-zesty-kernel.git] / drivers / usb / gadget / serial.c

diff --git a/drivers/usb/gadget/serial.c b/drivers/usb/gadget/serial.c
index c925d9222f53c4baaef730dd1046b8aa75620897..2e6926b33455b0197bb58179c922acd42dadf76c 100644 (file)
--- a/drivers/usb/gadget/serial.c
+++ b/drivers/usb/gadget/serial.c
@@ -300,18 +300,18 @@ static int gs_build_config_buf(u8 *buf, enum usb_device_speed speed,
                u8 type, unsigned int index, int is_otg);
 
 static struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned int len,
-       unsigned kmalloc_flags);
+       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,
-       unsigned kmalloc_flags);
+       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, unsigned kmalloc_flags);
+static int gs_alloc_ports(struct gs_dev *dev, gfp_t kmalloc_flags);
 static void gs_free_ports(struct gs_dev *dev);
 
 /* circular buffer */
-static struct gs_buf *gs_buf_alloc(unsigned int size, unsigned kmalloc_flags);
+static struct gs_buf *gs_buf_alloc(unsigned int size, gfp_t kmalloc_flags);
 static void gs_buf_free(struct gs_buf *gb);
 static void gs_buf_clear(struct gs_buf *gb);
 static unsigned int gs_buf_data_avail(struct gs_buf *gb);
@@ -890,10 +890,12 @@ static void gs_close(struct tty_struct *tty, struct file *file)
        /* wait for write buffer to drain, or */
        /* at most GS_CLOSE_TIMEOUT seconds */
        if (gs_buf_data_avail(port->port_write_buf) > 0) {
+               spin_unlock_irqrestore(&port->port_lock, flags);
                wait_cond_interruptible_timeout(port->port_write_wait,
                port->port_dev == NULL
                || gs_buf_data_avail(port->port_write_buf) == 0,
                &port->port_lock, flags, GS_CLOSE_TIMEOUT * HZ);
+               spin_lock_irqsave(&port->port_lock, flags);
        }
 
        /* free disconnected port on final close */
@@ -1269,6 +1271,7 @@ static int gs_recv_packet(struct gs_dev *dev, char *packet, unsigned int size)
        unsigned int len;
        struct gs_port *port;
        int ret;
+       struct tty_struct *tty;
 
        /* TEMPORARY -- only port 0 is supported right now */
        port = dev->dev_port[0];
@@ -1288,7 +1291,10 @@ static int gs_recv_packet(struct gs_dev *dev, char *packet, unsigned int size)
                goto exit;
        }
 
-       if (port->port_tty == NULL) {
+
+       tty = port->port_tty;
+
+       if (tty == NULL) {
                printk(KERN_ERR "gs_recv_packet: port=%d, NULL tty pointer\n",
                        port->port_num);
                ret = -EIO;
@@ -1302,20 +1308,13 @@ static int gs_recv_packet(struct gs_dev *dev, char *packet, unsigned int size)
                goto exit;
        }
 
-       len = (unsigned int)(TTY_FLIPBUF_SIZE - port->port_tty->flip.count);
-       if (len < size)
-               size = len;
-
-       if (size > 0) {
-               memcpy(port->port_tty->flip.char_buf_ptr, packet, size);
-               port->port_tty->flip.char_buf_ptr += size;
-               port->port_tty->flip.count += size;
+       len = tty_buffer_request_room(tty, size);
+       if (len > 0) {
+               tty_insert_flip_string(tty, packet, len);
                tty_flip_buffer_push(port->port_tty);
                wake_up_interruptible(&port->port_tty->read_wait);
        }
-
        ret = 0;
-
 exit:
        spin_unlock(&port->port_lock);
        return ret;
@@ -2091,7 +2090,7 @@ static int gs_build_config_buf(u8 *buf, enum usb_device_speed speed,
  * usb_request or NULL if there is an error.
  */
 static struct usb_request *
-gs_alloc_req(struct usb_ep *ep, unsigned int len, unsigned kmalloc_flags)
+gs_alloc_req(struct usb_ep *ep, unsigned int len, gfp_t kmalloc_flags)
 {
        struct usb_request *req;
 
@@ -2132,7 +2131,7 @@ static void gs_free_req(struct usb_ep *ep, struct usb_request *req)
  * endpoint, buffer len, and kmalloc flags.
  */
 static struct gs_req_entry *
-gs_alloc_req_entry(struct usb_ep *ep, unsigned len, unsigned kmalloc_flags)
+gs_alloc_req_entry(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags)
 {
        struct gs_req_entry     *req;
 
@@ -2173,7 +2172,7 @@ static void gs_free_req_entry(struct usb_ep *ep, struct gs_req_entry *req)
  *
  * The device lock is normally held when calling this function.
  */
-static int gs_alloc_ports(struct gs_dev *dev, unsigned kmalloc_flags)
+static int gs_alloc_ports(struct gs_dev *dev, gfp_t kmalloc_flags)
 {
        int i;
        struct gs_port *port;
@@ -2255,7 +2254,7 @@ static void gs_free_ports(struct gs_dev *dev)
  *
  * Allocate a circular buffer and all associated memory.
  */
-static struct gs_buf *gs_buf_alloc(unsigned int size, unsigned kmalloc_flags)
+static struct gs_buf *gs_buf_alloc(unsigned int size, gfp_t kmalloc_flags)
 {
        struct gs_buf *gb;