diff options
Diffstat (limited to 'drivers/usb/storage/usb.c')
| -rw-r--r-- | drivers/usb/storage/usb.c | 90 |
1 files changed, 31 insertions, 59 deletions
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c index 3dd7da9fd50..db51ba16dc0 100644 --- a/drivers/usb/storage/usb.c +++ b/drivers/usb/storage/usb.c @@ -788,15 +788,19 @@ static void quiesce_and_remove_host(struct us_data *us) struct Scsi_Host *host = us_to_host(us); /* If the device is really gone, cut short reset delays */ - if (us->pusb_dev->state == USB_STATE_NOTATTACHED) + if (us->pusb_dev->state == USB_STATE_NOTATTACHED) { set_bit(US_FLIDX_DISCONNECTING, &us->dflags); + wake_up(&us->delay_wait); + } - /* Prevent SCSI-scanning (if it hasn't started yet) - * and wait for the SCSI-scanning thread to stop. + /* Prevent SCSI scanning (if it hasn't started yet) + * or wait for the SCSI-scanning routine to stop. */ - set_bit(US_FLIDX_DONT_SCAN, &us->dflags); - wake_up(&us->delay_wait); - wait_for_completion(&us->scanning_done); + cancel_delayed_work_sync(&us->scan_dwork); + + /* Balance autopm calls if scanning was cancelled */ + if (test_bit(US_FLIDX_SCAN_PENDING, &us->dflags)) + usb_autopm_put_interface_no_suspend(us->pusb_intf); /* Removing the host will perform an orderly shutdown: caches * synchronized, disks spun down, etc. @@ -823,53 +827,28 @@ static void release_everything(struct us_data *us) scsi_host_put(us_to_host(us)); } -/* Thread to carry out delayed SCSI-device scanning */ -static int usb_stor_scan_thread(void * __us) +/* Delayed-work routine to carry out SCSI-device scanning */ +static void usb_stor_scan_dwork(struct work_struct *work) { - struct us_data *us = (struct us_data *)__us; + struct us_data *us = container_of(work, struct us_data, + scan_dwork.work); struct device *dev = &us->pusb_intf->dev; - dev_dbg(dev, "device found\n"); - - set_freezable(); + dev_dbg(dev, "starting scan\n"); - /* - * Wait for the timeout to expire or for a disconnect - * - * We can't freeze in this thread or we risk causing khubd to - * fail to freeze, but we can't be non-freezable either. Nor can - * khubd freeze while waiting for scanning to complete as it may - * hold the device lock, causing a hang when suspending devices. - * So instead of using wait_event_freezable(), explicitly test - * for (DONT_SCAN || freezing) in interruptible wait and proceed - * if any of DONT_SCAN, freezing or timeout has happened. - */ - if (delay_use > 0) { - dev_dbg(dev, "waiting for device to settle " - "before scanning\n"); - wait_event_interruptible_timeout(us->delay_wait, - test_bit(US_FLIDX_DONT_SCAN, &us->dflags) || - freezing(current), delay_use * HZ); + /* For bulk-only devices, determine the max LUN value */ + if (us->protocol == USB_PR_BULK && !(us->fflags & US_FL_SINGLE_LUN)) { + mutex_lock(&us->dev_mutex); + us->max_lun = usb_stor_Bulk_max_lun(us); + mutex_unlock(&us->dev_mutex); } + scsi_scan_host(us_to_host(us)); + dev_dbg(dev, "scan complete\n"); - /* If the device is still connected, perform the scanning */ - if (!test_bit(US_FLIDX_DONT_SCAN, &us->dflags)) { - - /* For bulk-only devices, determine the max LUN value */ - if (us->protocol == USB_PR_BULK && - !(us->fflags & US_FL_SINGLE_LUN)) { - mutex_lock(&us->dev_mutex); - us->max_lun = usb_stor_Bulk_max_lun(us); - mutex_unlock(&us->dev_mutex); - } - scsi_scan_host(us_to_host(us)); - dev_dbg(dev, "scan complete\n"); - - /* Should we unbind if no devices were detected? */ - } + /* Should we unbind if no devices were detected? */ usb_autopm_put_interface(us->pusb_intf); - complete_and_exit(&us->scanning_done, 0); + clear_bit(US_FLIDX_SCAN_PENDING, &us->dflags); } static unsigned int usb_stor_sg_tablesize(struct usb_interface *intf) @@ -916,7 +895,7 @@ int usb_stor_probe1(struct us_data **pus, init_completion(&us->cmnd_ready); init_completion(&(us->notify)); init_waitqueue_head(&us->delay_wait); - init_completion(&us->scanning_done); + INIT_DELAYED_WORK(&us->scan_dwork, usb_stor_scan_dwork); /* Associate the us_data structure with the USB device */ result = associate_dev(us, intf); @@ -947,7 +926,6 @@ EXPORT_SYMBOL_GPL(usb_stor_probe1); /* Second part of general USB mass-storage probing */ int usb_stor_probe2(struct us_data *us) { - struct task_struct *th; int result; struct device *dev = &us->pusb_intf->dev; @@ -988,20 +966,14 @@ int usb_stor_probe2(struct us_data *us) goto BadDevice; } - /* Start up the thread for delayed SCSI-device scanning */ - th = kthread_create(usb_stor_scan_thread, us, "usb-stor-scan"); - if (IS_ERR(th)) { - dev_warn(dev, - "Unable to start the device-scanning thread\n"); - complete(&us->scanning_done); - quiesce_and_remove_host(us); - result = PTR_ERR(th); - goto BadDevice; - } - + /* Submit the delayed_work for SCSI-device scanning */ usb_autopm_get_interface_no_resume(us->pusb_intf); - wake_up_process(th); + set_bit(US_FLIDX_SCAN_PENDING, &us->dflags); + if (delay_use > 0) + dev_dbg(dev, "waiting for device to settle before scanning\n"); + queue_delayed_work(system_freezable_wq, &us->scan_dwork, + delay_use * HZ); return 0; /* We come here if there are any problems */ |