re: uas: Use GFP_NOIO rather then GFP_ATOMIC where possible

re: uas: Use GFP_NOIO rather then GFP_ATOMIC where possible

[Dan Carpenter]

Hello Hans de Goede,

The patch e36e64930cff: "uas: Use GFP_NOIO rather then GFP_ATOMIC
where possible" from Nov 7, 2013, leads to the following static
checker warning:

	drivers/usb/storage/uas.c:806 uas_eh_task_mgmt()
	error: scheduling with locks held: 'spin_lock:lock'

drivers/usb/storage/uas.c
   789          spin_lock_irqsave(&devinfo->lock, flags);
   790  
   791          if (devinfo->resetting) {
   792                  spin_unlock_irqrestore(&devinfo->lock, flags);
   793                  return FAILED;
   794          }
   795  
   796          if (devinfo->running_task) {
   797                  shost_printk(KERN_INFO, shost,
   798                               "%s: %s: error already running a task\n",
   799                               __func__, fname);
   800                  spin_unlock_irqrestore(&devinfo->lock, flags);
   801                  return FAILED;
   802          }
   803  
   804          devinfo->running_task = 1;
   805          memset(&devinfo->response, 0, sizeof(devinfo->response));
   806          sense_urb = uas_submit_sense_urb(cmnd, GFP_NOIO,
                                                       ^^^^^^^^
The original code had this as GFP_ATOMIC because we can't sleep while
we have spin_lock_irqsave() held.

   807                                           devinfo->use_streams ? tag : 0);
   808          if (!sense_urb) {
   809                  shost_printk(KERN_INFO, shost,
   810                               "%s: %s: submit sense urb failed\n",
   811                               __func__, fname);
   812                  devinfo->running_task = 0;
   813                  spin_unlock_irqrestore(&devinfo->lock, flags);
   814                  return FAILED;
   815          }
   816          if (uas_submit_task_urb(cmnd, GFP_NOIO, function, tag)) {
                                              ^^^^^^^^
Same.

   817                  shost_printk(KERN_INFO, shost,
   818                               "%s: %s: submit task mgmt urb failed\n",
   819                               __func__, fname);
   820                  devinfo->running_task = 0;
   821                  spin_unlock_irqrestore(&devinfo->lock, flags);
   822                  usb_kill_urb(sense_urb);
   823                  return FAILED;
   824          }
   825          spin_unlock_irqrestore(&devinfo->lock, flags);

regards,
dan carpenter