USB: convert usb_hcd bitfields into atomic flags
This patch (as1393) converts several of the single-bit fields in
struct usb_hcd to atomic flags. This is for safety's sake; not all
CPUs can update bitfield values atomically, and these flags are used
in multiple contexts.
The flag fields that are set only during registration or removal can
remain as they are, since non-atomic accesses at those times will not
cause any problems.
(Strictly speaking, the authorized_default flag should become atomic
as well. I didn't bother with it because it gets changed only via
sysfs. It can be done later, if anyone wants.)
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index 53f14c8..f2fe7c8 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -679,7 +679,7 @@
spin_lock_irqsave(&hcd_root_hub_lock, flags);
urb = hcd->status_urb;
if (urb) {
- hcd->poll_pending = 0;
+ clear_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
hcd->status_urb = NULL;
urb->actual_length = length;
memcpy(urb->transfer_buffer, buffer, length);
@@ -690,7 +690,7 @@
spin_lock(&hcd_root_hub_lock);
} else {
length = 0;
- hcd->poll_pending = 1;
+ set_bit(HCD_FLAG_POLL_PENDING, &hcd->flags);
}
spin_unlock_irqrestore(&hcd_root_hub_lock, flags);
}
@@ -699,7 +699,7 @@
* exceed that limit if HZ is 100. The math is more clunky than
* maybe expected, this is to make sure that all timers for USB devices
* fire at the same time to give the CPU a break inbetween */
- if (hcd->uses_new_polling ? hcd->poll_rh :
+ if (hcd->uses_new_polling ? HCD_POLL_RH(hcd) :
(length == 0 && hcd->status_urb != NULL))
mod_timer (&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
}
@@ -736,7 +736,7 @@
mod_timer(&hcd->rh_timer, (jiffies/(HZ/4) + 1) * (HZ/4));
/* If a status change has already occurred, report it ASAP */
- else if (hcd->poll_pending)
+ else if (HCD_POLL_PENDING(hcd))
mod_timer(&hcd->rh_timer, jiffies);
retval = 0;
done:
@@ -1150,8 +1150,7 @@
* finish unlinking the initial failed usb_set_address()
* or device descriptor fetch.
*/
- if (!test_bit(HCD_FLAG_SAW_IRQ, &hcd->flags) &&
- !is_root_hub(urb->dev)) {
+ if (!HCD_SAW_IRQ(hcd) && !is_root_hub(urb->dev)) {
dev_warn(hcd->self.controller, "Unlink after no-IRQ? "
"Controller is probably using the wrong IRQ.\n");
set_bit(HCD_FLAG_SAW_IRQ, &hcd->flags);
@@ -2063,8 +2062,7 @@
*/
local_irq_save(flags);
- if (unlikely(hcd->state == HC_STATE_HALT ||
- !test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags))) {
+ if (unlikely(hcd->state == HC_STATE_HALT || !HCD_HW_ACCESSIBLE(hcd))) {
rc = IRQ_NONE;
} else if (hcd->driver->irq(hcd) == IRQ_NONE) {
rc = IRQ_NONE;
@@ -2098,7 +2096,7 @@
spin_lock_irqsave (&hcd_root_hub_lock, flags);
if (hcd->rh_registered) {
- hcd->poll_rh = 0;
+ clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
/* make khubd clean up old urbs and devices */
usb_set_device_state (hcd->self.root_hub,
@@ -2301,7 +2299,7 @@
retval);
goto error_create_attr_group;
}
- if (hcd->uses_new_polling && hcd->poll_rh)
+ if (hcd->uses_new_polling && HCD_POLL_RH(hcd))
usb_hcd_poll_rh_status(hcd);
return retval;
@@ -2320,11 +2318,11 @@
mutex_unlock(&usb_bus_list_lock);
err_register_root_hub:
hcd->rh_pollable = 0;
- hcd->poll_rh = 0;
+ clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
del_timer_sync(&hcd->rh_timer);
hcd->driver->stop(hcd);
hcd->state = HC_STATE_HALT;
- hcd->poll_rh = 0;
+ clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
del_timer_sync(&hcd->rh_timer);
err_hcd_driver_start:
if (hcd->irq >= 0)
@@ -2380,14 +2378,14 @@
* the hub_status_data() callback.
*/
hcd->rh_pollable = 0;
- hcd->poll_rh = 0;
+ clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
del_timer_sync(&hcd->rh_timer);
hcd->driver->stop(hcd);
hcd->state = HC_STATE_HALT;
/* In case the HCD restarted the timer, stop it again. */
- hcd->poll_rh = 0;
+ clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
del_timer_sync(&hcd->rh_timer);
if (hcd->irq >= 0)