From a19c26190145ee9355cfe1a755217b83040314db Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Tue, 29 Sep 2020 22:25:31 +0200 Subject: [PATCH] net: usb: kaweth: Remove last user of kaweth_control() kaweth_async_set_rx_mode() invokes kaweth_contol() and has two callers: - kaweth_open() which is invoked from preemptible context . - kaweth_start_xmit() which holds a spinlock and has bottom halfs disabled. If called from kaweth_start_xmit() kaweth_async_set_rx_mode() obviously cannot block, which means it can't call kaweth_control(). This is detected with an in_interrupt() check. Replace the in_interrupt() check in kaweth_async_set_rx_mode() with an argument which is set true by the caller if the context is safe to sleep, otherwise false. Now kaweth_control() is only called from preemptible context which means there is no need for GFP_ATOMIC allocations anymore. Replace it with usb_control_msg(). Cleanup the code a bit while at it. Finally remove kaweth_control() since the last user is gone. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner Reviewed-by: Greg Kroah-Hartman Signed-off-by: David S. Miller --- drivers/net/usb/kaweth.c | 168 +++++------------------------------------------ 1 file changed, 17 insertions(+), 151 deletions(-) diff --git a/drivers/net/usb/kaweth.c b/drivers/net/usb/kaweth.c index 25eeb15104ee..144c686b4333 100644 --- a/drivers/net/usb/kaweth.c +++ b/drivers/net/usb/kaweth.c @@ -103,10 +103,6 @@ static int kaweth_probe( const struct usb_device_id *id /* from id_table */ ); static void kaweth_disconnect(struct usb_interface *intf); -static int kaweth_internal_control_msg(struct usb_device *usb_dev, - unsigned int pipe, - struct usb_ctrlrequest *cmd, void *data, - int len, int timeout); static int kaweth_suspend(struct usb_interface *intf, pm_message_t message); static int kaweth_resume(struct usb_interface *intf); @@ -236,48 +232,6 @@ struct kaweth_device }; /**************************************************************** - * kaweth_control - ****************************************************************/ -static int kaweth_control(struct kaweth_device *kaweth, - unsigned int pipe, - __u8 request, - __u8 requesttype, - __u16 value, - __u16 index, - void *data, - __u16 size, - int timeout) -{ - struct usb_ctrlrequest *dr; - int retval; - - if(in_interrupt()) { - netdev_dbg(kaweth->net, "in_interrupt()\n"); - return -EBUSY; - } - - dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_ATOMIC); - if (!dr) - return -ENOMEM; - - dr->bRequestType = requesttype; - dr->bRequest = request; - dr->wValue = cpu_to_le16(value); - dr->wIndex = cpu_to_le16(index); - dr->wLength = cpu_to_le16(size); - - retval = kaweth_internal_control_msg(kaweth->dev, - pipe, - dr, - data, - size, - timeout); - - kfree(dr); - return retval; -} - -/**************************************************************** * kaweth_read_configuration ****************************************************************/ static int kaweth_read_configuration(struct kaweth_device *kaweth) @@ -531,7 +485,8 @@ static int kaweth_resubmit_rx_urb(struct kaweth_device *kaweth, return result; } -static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth); +static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth, + bool may_sleep); /**************************************************************** * kaweth_usb_receive @@ -661,7 +616,7 @@ static int kaweth_open(struct net_device *net) netif_start_queue(net); - kaweth_async_set_rx_mode(kaweth); + kaweth_async_set_rx_mode(kaweth, true); return 0; err_out: @@ -749,7 +704,7 @@ static netdev_tx_t kaweth_start_xmit(struct sk_buff *skb, spin_lock_irq(&kaweth->device_lock); - kaweth_async_set_rx_mode(kaweth); + kaweth_async_set_rx_mode(kaweth, false); netif_stop_queue(net); if (IS_BLOCKED(kaweth->status)) { goto skip; @@ -826,36 +781,31 @@ static void kaweth_set_rx_mode(struct net_device *net) /**************************************************************** * kaweth_async_set_rx_mode ****************************************************************/ -static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth) +static void kaweth_async_set_rx_mode(struct kaweth_device *kaweth, + bool may_sleep) { - int result; + int ret; __u16 packet_filter_bitmap = kaweth->packet_filter_bitmap; kaweth->packet_filter_bitmap = 0; if (packet_filter_bitmap == 0) return; - if (in_interrupt()) + if (!may_sleep) return; - result = kaweth_control(kaweth, - usb_sndctrlpipe(kaweth->dev, 0), - KAWETH_COMMAND_SET_PACKET_FILTER, - USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE, - packet_filter_bitmap, - 0, - (void *)&kaweth->scratch, - 0, - KAWETH_CONTROL_TIMEOUT); - - if(result < 0) { + ret = usb_control_msg(kaweth->dev, usb_sndctrlpipe(kaweth->dev, 0), + KAWETH_COMMAND_SET_PACKET_FILTER, + USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE, + packet_filter_bitmap, 0, + &kaweth->scratch, 0, + KAWETH_CONTROL_TIMEOUT); + if (ret < 0) dev_err(&kaweth->intf->dev, "Failed to set Rx mode: %d\n", - result); - } - else { + ret); + else netdev_dbg(kaweth->net, "Set Rx mode to %d\n", packet_filter_bitmap); - } } /**************************************************************** @@ -1163,88 +1113,4 @@ static void kaweth_disconnect(struct usb_interface *intf) } -// FIXME this completion stuff is a modified clone of -// an OLD version of some stuff in usb.c ... -struct usb_api_data { - wait_queue_head_t wqh; - int done; -}; - -/*-------------------------------------------------------------------* - * completion handler for compatibility wrappers (sync control/bulk) * - *-------------------------------------------------------------------*/ -static void usb_api_blocking_completion(struct urb *urb) -{ - struct usb_api_data *awd = (struct usb_api_data *)urb->context; - - awd->done=1; - wake_up(&awd->wqh); -} - -/*-------------------------------------------------------------------* - * COMPATIBILITY STUFF * - *-------------------------------------------------------------------*/ - -// Starts urb and waits for completion or timeout -static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length) -{ - struct usb_api_data awd; - int status; - - init_waitqueue_head(&awd.wqh); - awd.done = 0; - - urb->context = &awd; - status = usb_submit_urb(urb, GFP_ATOMIC); - if (status) { - // something went wrong - usb_free_urb(urb); - return status; - } - - if (!wait_event_timeout(awd.wqh, awd.done, timeout)) { - // timeout - dev_warn(&urb->dev->dev, "usb_control/bulk_msg: timeout\n"); - usb_kill_urb(urb); // remove urb safely - status = -ETIMEDOUT; - } - else { - status = urb->status; - } - - if (actual_length) { - *actual_length = urb->actual_length; - } - - usb_free_urb(urb); - return status; -} - -/*-------------------------------------------------------------------*/ -// returns status (negative) or length (positive) -static int kaweth_internal_control_msg(struct usb_device *usb_dev, - unsigned int pipe, - struct usb_ctrlrequest *cmd, void *data, - int len, int timeout) -{ - struct urb *urb; - int retv; - int length = 0; /* shut up GCC */ - - urb = usb_alloc_urb(0, GFP_ATOMIC); - if (!urb) - return -ENOMEM; - - usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char*)cmd, data, - len, usb_api_blocking_completion, NULL); - - retv = usb_start_wait_urb(urb, timeout, &length); - if (retv < 0) { - return retv; - } - else { - return length; - } -} - module_usb_driver(kaweth_driver); -- 2.11.0