diff options
| -rw-r--r-- | drivers/hid/usbhid/hid-core.c | 61 | ||||
| -rw-r--r-- | drivers/usb/core/urb.c | 21 | ||||
| -rw-r--r-- | include/linux/usb.h | 3 |
3 files changed, 79 insertions, 6 deletions
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c index 5bf91dbad59d..4bbb883a3dd2 100644 --- a/drivers/hid/usbhid/hid-core.c +++ b/drivers/hid/usbhid/hid-core.c @@ -399,6 +399,16 @@ static int hid_submit_ctrl(struct hid_device *hid) * Output interrupt completion handler. */ +static int irq_out_pump_restart(struct hid_device *hid) +{ + struct usbhid_device *usbhid = hid->driver_data; + + if (usbhid->outhead != usbhid->outtail) + return hid_submit_out(hid); + else + return -1; +} + static void hid_irq_out(struct urb *urb) { struct hid_device *hid = urb->context; @@ -428,7 +438,7 @@ static void hid_irq_out(struct urb *urb) else usbhid->outtail = (usbhid->outtail + 1) & (HID_OUTPUT_FIFO_SIZE - 1); - if (usbhid->outhead != usbhid->outtail && !hid_submit_out(hid)) { + if (!irq_out_pump_restart(hid)) { /* Successfully submitted next urb in queue */ spin_unlock_irqrestore(&usbhid->lock, flags); return; @@ -443,6 +453,15 @@ static void hid_irq_out(struct urb *urb) /* * Control pipe completion handler. */ +static int ctrl_pump_restart(struct hid_device *hid) +{ + struct usbhid_device *usbhid = hid->driver_data; + + if (usbhid->ctrlhead != usbhid->ctrltail) + return hid_submit_ctrl(hid); + else + return -1; +} static void hid_ctrl(struct urb *urb) { @@ -476,7 +495,7 @@ static void hid_ctrl(struct urb *urb) else usbhid->ctrltail = (usbhid->ctrltail + 1) & (HID_CONTROL_FIFO_SIZE - 1); - if (usbhid->ctrlhead != usbhid->ctrltail && !hid_submit_ctrl(hid)) { + if (!ctrl_pump_restart(hid)) { /* Successfully submitted next urb in queue */ spin_unlock(&usbhid->lock); return; @@ -535,11 +554,27 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re * the queue is known to run * but an earlier request may be stuck * we may need to time out - * no race because this is called under + * no race because the URB is blocked under * spinlock */ - if (time_after(jiffies, usbhid->last_out + HZ * 5)) + if (time_after(jiffies, usbhid->last_out + HZ * 5)) { + usb_block_urb(usbhid->urbout); + /* drop lock to not deadlock if the callback is called */ + spin_unlock(&usbhid->lock); usb_unlink_urb(usbhid->urbout); + spin_lock(&usbhid->lock); + usb_unblock_urb(usbhid->urbout); + /* + * if the unlinking has already completed + * the pump will have been stopped + * it must be restarted now + */ + if (!test_bit(HID_OUT_RUNNING, &usbhid->iofl)) + if (!irq_out_pump_restart(hid)) + set_bit(HID_OUT_RUNNING, &usbhid->iofl); + + + } } return; } @@ -583,11 +618,25 @@ static void __usbhid_submit_report(struct hid_device *hid, struct hid_report *re * the queue is known to run * but an earlier request may be stuck * we may need to time out - * no race because this is called under + * no race because the URB is blocked under * spinlock */ - if (time_after(jiffies, usbhid->last_ctrl + HZ * 5)) + if (time_after(jiffies, usbhid->last_ctrl + HZ * 5)) { + usb_block_urb(usbhid->urbctrl); + /* drop lock to not deadlock if the callback is called */ + spin_unlock(&usbhid->lock); usb_unlink_urb(usbhid->urbctrl); + spin_lock(&usbhid->lock); + usb_unblock_urb(usbhid->urbctrl); + /* + * if the unlinking has already completed + * the pump will have been stopped + * it must be restarted now + */ + if (!test_bit(HID_CTRL_RUNNING, &usbhid->iofl)) + if (!ctrl_pump_restart(hid)) + set_bit(HID_CTRL_RUNNING, &usbhid->iofl); + } } } diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c index cd9b3a2cd8a7..9d912bfdcffe 100644 --- a/drivers/usb/core/urb.c +++ b/drivers/usb/core/urb.c @@ -681,6 +681,27 @@ void usb_unpoison_urb(struct urb *urb) EXPORT_SYMBOL_GPL(usb_unpoison_urb); /** + * usb_block_urb - reliably prevent further use of an URB + * @urb: pointer to URB to be blocked, may be NULL + * + * After the routine has run, attempts to resubmit the URB will fail + * with error -EPERM. Thus even if the URB's completion handler always + * tries to resubmit, it will not succeed and the URB will become idle. + * + * The URB must not be deallocated while this routine is running. In + * particular, when a driver calls this routine, it must insure that the + * completion handler cannot deallocate the URB. + */ +void usb_block_urb(struct urb *urb) +{ + if (!urb) + return; + + atomic_inc(&urb->reject); +} +EXPORT_SYMBOL_GPL(usb_block_urb); + +/** * usb_kill_anchored_urbs - cancel transfer requests en masse * @anchor: anchor the requests are bound to * diff --git a/include/linux/usb.h b/include/linux/usb.h index 8fa9a93a4ec4..5483cd70390b 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -1369,6 +1369,7 @@ extern int usb_unlink_urb(struct urb *urb); extern void usb_kill_urb(struct urb *urb); extern void usb_poison_urb(struct urb *urb); extern void usb_unpoison_urb(struct urb *urb); +extern void usb_block_urb(struct urb *urb); extern void usb_kill_anchored_urbs(struct usb_anchor *anchor); extern void usb_poison_anchored_urbs(struct usb_anchor *anchor); extern void usb_unpoison_anchored_urbs(struct usb_anchor *anchor); @@ -1381,6 +1382,8 @@ extern struct urb *usb_get_from_anchor(struct usb_anchor *anchor); extern void usb_scuttle_anchored_urbs(struct usb_anchor *anchor); extern int usb_anchor_empty(struct usb_anchor *anchor); +#define usb_unblock_urb usb_unpoison_urb + /** * usb_urb_dir_in - check if an URB describes an IN transfer * @urb: URB to be checked |