diff options
| -rw-r--r-- | drivers/usb/core/hcd.c | 316 |
1 files changed, 166 insertions, 150 deletions
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index f8e7deb03ee9..eb2121788264 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -914,99 +914,117 @@ EXPORT_SYMBOL (usb_calc_bus_time); /*-------------------------------------------------------------------------*/ -static void urb_unlink(struct usb_hcd *hcd, struct urb *urb) +static int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb) { - unsigned long flags; + unsigned long flags; + int rc = 0; - /* clear all state linking urb to this dev (and hcd) */ spin_lock_irqsave(&hcd_urb_list_lock, flags); - list_del_init (&urb->urb_list); - spin_unlock_irqrestore(&hcd_urb_list_lock, flags); - if (hcd->self.uses_dma && !is_root_hub(urb->dev)) { - if (usb_endpoint_xfer_control(&urb->ep->desc) - && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) - dma_unmap_single (hcd->self.controller, urb->setup_dma, - sizeof (struct usb_ctrlrequest), - DMA_TO_DEVICE); - if (urb->transfer_buffer_length != 0 - && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) - dma_unmap_single (hcd->self.controller, - urb->transfer_dma, - urb->transfer_buffer_length, - usb_urb_dir_in(urb) - ? DMA_FROM_DEVICE - : DMA_TO_DEVICE); + /* Check that the URB isn't being killed */ + if (unlikely(urb->reject)) { + rc = -EPERM; + goto done; } -} - -/* may be called in any context with a valid urb->dev usecount - * caller surrenders "ownership" of urb - * expects usb_submit_urb() to have sanity checked and conditioned all - * inputs in the urb - */ -int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) -{ - int status; - struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); - unsigned long flags; - - if (!hcd) - return -ENODEV; - usbmon_urb_submit(&hcd->self, urb); + if (unlikely(!urb->ep->enabled)) { + rc = -ENOENT; + goto done; + } /* - * Atomically queue the urb, first to our records, then to the HCD. - * Access to urb->status is controlled by urb->lock ... changes on - * i/o completion (normal or fault) or unlinking. + * Check the host controller's state and add the URB to the + * endpoint's queue. */ - - // FIXME: verify that quiescing hc works right (RH cleans up) - - spin_lock_irqsave(&hcd_urb_list_lock, flags); - if (unlikely(!urb->ep->enabled)) - status = -ENOENT; - else if (unlikely (urb->reject)) - status = -EPERM; - else switch (hcd->state) { + switch (hcd->state) { case HC_STATE_RUNNING: case HC_STATE_RESUMING: - list_add_tail (&urb->urb_list, &urb->ep->urb_list); - status = 0; + list_add_tail(&urb->urb_list, &urb->ep->urb_list); break; default: - status = -ESHUTDOWN; - break; + rc = -ESHUTDOWN; + goto done; } + done: spin_unlock_irqrestore(&hcd_urb_list_lock, flags); - if (status) { - INIT_LIST_HEAD (&urb->urb_list); - usbmon_urb_submit_error(&hcd->self, urb, status); - return status; + return rc; +} + +static int usb_hcd_check_unlink_urb(struct usb_hcd *hcd, struct urb *urb, + int status) +{ + unsigned long flags; + struct list_head *tmp; + int rc = 0; + + /* + * we contend for urb->status with the hcd core, + * which changes it while returning the urb. + * + * Caller guaranteed that the urb pointer hasn't been freed, and + * that it was submitted. But as a rule it can't know whether or + * not it's already been unlinked ... so we respect the reversed + * lock sequence needed for the usb_hcd_giveback_urb() code paths + * (urb lock, then hcd_urb_list_lock) in case some other CPU is now + * unlinking it. + */ + spin_lock_irqsave(&urb->lock, flags); + spin_lock(&hcd_urb_list_lock); + + /* insist the urb is still queued */ + list_for_each(tmp, &urb->ep->urb_list) { + if (tmp == &urb->urb_list) + break; + } + if (tmp != &urb->urb_list) { + rc = -EIDRM; + goto done; } - /* increment urb's reference count as part of giving it to the HCD - * (which now controls it). HCD guarantees that it either returns - * an error or calls giveback(), but not both. + /* Any status except -EINPROGRESS means something already started to + * unlink this URB from the hardware. So there's no more work to do. */ - urb = usb_get_urb (urb); - atomic_inc (&urb->use_count); - - if (is_root_hub(urb->dev)) { - /* NOTE: requirement on hub callers (usbfs and the hub - * driver, for now) that URBs' urb->transfer_buffer be - * valid and usb_buffer_{sync,unmap}() not be needed, since - * they could clobber root hub response data. - */ - status = rh_urb_enqueue (hcd, urb); + if (urb->status != -EINPROGRESS) { + rc = -EBUSY; goto done; } + urb->status = status; + + /* IRQ setup can easily be broken so that USB controllers + * never get completion IRQs ... maybe even the ones we need to + * 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)) { + 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); + } + + done: + spin_unlock(&hcd_urb_list_lock); + spin_unlock_irqrestore (&urb->lock, flags); + return rc; +} + +static void usb_hcd_unlink_urb_from_ep(struct usb_hcd *hcd, struct urb *urb) +{ + unsigned long flags; - /* lower level hcd code should use *_dma exclusively, + /* clear all state linking urb to this dev (and hcd) */ + spin_lock_irqsave(&hcd_urb_list_lock, flags); + list_del_init(&urb->urb_list); + spin_unlock_irqrestore(&hcd_urb_list_lock, flags); +} + +static void map_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) +{ + /* Map the URB's buffers for DMA access. + * Lower level HCD code should use *_dma exclusively, * unless it uses pio or talks to another transport. */ - if (hcd->self.uses_dma) { + if (hcd->self.uses_dma && !is_root_hub(urb->dev)) { if (usb_endpoint_xfer_control(&urb->ep->desc) && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) urb->setup_dma = dma_map_single ( @@ -1024,16 +1042,73 @@ int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) ? DMA_FROM_DEVICE : DMA_TO_DEVICE); } +} - status = hcd->driver->urb_enqueue (hcd, urb->ep, urb, mem_flags); -done: - if (unlikely (status)) { - urb_unlink(hcd, urb); - atomic_dec (&urb->use_count); - if (urb->reject) - wake_up (&usb_kill_urb_queue); +static void unmap_urb_for_dma(struct usb_hcd *hcd, struct urb *urb) +{ + if (hcd->self.uses_dma && !is_root_hub(urb->dev)) { + if (usb_endpoint_xfer_control(&urb->ep->desc) + && !(urb->transfer_flags & URB_NO_SETUP_DMA_MAP)) + dma_unmap_single(hcd->self.controller, urb->setup_dma, + sizeof(struct usb_ctrlrequest), + DMA_TO_DEVICE); + if (urb->transfer_buffer_length != 0 + && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)) + dma_unmap_single(hcd->self.controller, + urb->transfer_dma, + urb->transfer_buffer_length, + usb_urb_dir_in(urb) + ? DMA_FROM_DEVICE + : DMA_TO_DEVICE); + } +} + +/*-------------------------------------------------------------------------*/ + +/* may be called in any context with a valid urb->dev usecount + * caller surrenders "ownership" of urb + * expects usb_submit_urb() to have sanity checked and conditioned all + * inputs in the urb + */ +int usb_hcd_submit_urb (struct urb *urb, gfp_t mem_flags) +{ + int status; + struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); + + /* increment urb's reference count as part of giving it to the HCD + * (which will control it). HCD guarantees that it either returns + * an error or calls giveback(), but not both. + */ + usb_get_urb(urb); + atomic_inc(&urb->use_count); + usbmon_urb_submit(&hcd->self, urb); + + /* NOTE requirements on root-hub callers (usbfs and the hub + * driver, for now): URBs' urb->transfer_buffer must be + * valid and usb_buffer_{sync,unmap}() not be needed, since + * they could clobber root hub response data. Also, control + * URBs must be submitted in process context with interrupts + * enabled. + */ + status = usb_hcd_link_urb_to_ep(hcd, urb); + if (!status) { + map_urb_for_dma(hcd, urb); + if (is_root_hub(urb->dev)) + status = rh_urb_enqueue(hcd, urb); + else + status = hcd->driver->urb_enqueue(hcd, urb->ep, urb, + mem_flags); + } + + if (unlikely(status)) { usbmon_urb_submit_error(&hcd->self, urb, status); - usb_put_urb (urb); + unmap_urb_for_dma(hcd, urb); + usb_hcd_unlink_urb_from_ep(hcd, urb); + INIT_LIST_HEAD(&urb->urb_list); + atomic_dec(&urb->use_count); + if (urb->reject) + wake_up(&usb_kill_urb_queue); + usb_put_urb(urb); } return status; } @@ -1074,78 +1149,20 @@ unlink1 (struct usb_hcd *hcd, struct urb *urb) */ int usb_hcd_unlink_urb (struct urb *urb, int status) { - struct usb_hcd *hcd = NULL; - struct device *sys = NULL; - unsigned long flags; - struct list_head *tmp; - int retval; - - /* - * we contend for urb->status with the hcd core, - * which changes it while returning the urb. - * - * Caller guaranteed that the urb pointer hasn't been freed, and - * that it was submitted. But as a rule it can't know whether or - * not it's already been unlinked ... so we respect the reversed - * lock sequence needed for the usb_hcd_giveback_urb() code paths - * (urb lock, then hcd_urb_list_lock) in case some other CPU is now - * unlinking it. - */ - spin_lock_irqsave (&urb->lock, flags); - spin_lock(&hcd_urb_list_lock); + struct usb_hcd *hcd; + int retval; - sys = &urb->dev->dev; hcd = bus_to_hcd(urb->dev->bus); - if (hcd == NULL) { - retval = -ENODEV; - goto done; - } - - /* insist the urb is still queued */ - list_for_each(tmp, &urb->ep->urb_list) { - if (tmp == &urb->urb_list) - break; - } - if (tmp != &urb->urb_list) { - retval = -EIDRM; - goto done; - } - /* Any status except -EINPROGRESS means something already started to - * unlink this URB from the hardware. So there's no more work to do. - */ - if (urb->status != -EINPROGRESS) { - retval = -EBUSY; - goto done; - } + retval = usb_hcd_check_unlink_urb(hcd, urb, status); + if (!retval) + retval = unlink1(hcd, urb); - /* IRQ setup can easily be broken so that USB controllers - * never get completion IRQs ... maybe even the ones we need to - * 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)) { - 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); - } - - urb->status = status; - - spin_unlock(&hcd_urb_list_lock); - spin_unlock_irqrestore (&urb->lock, flags); - - retval = unlink1 (hcd, urb); if (retval == 0) retval = -EINPROGRESS; - return retval; - -done: - spin_unlock(&hcd_urb_list_lock); - spin_unlock_irqrestore (&urb->lock, flags); - if (retval != -EIDRM && sys && sys->driver) - dev_dbg (sys, "hcd_unlink_urb %p fail %d\n", urb, retval); + else if (retval != -EIDRM) + dev_dbg(&urb->dev->dev, "hcd_unlink_urb %p fail %d\n", + urb, retval); return retval; } @@ -1165,7 +1182,8 @@ done: */ void usb_hcd_giveback_urb (struct usb_hcd *hcd, struct urb *urb) { - urb_unlink(hcd, urb); + usb_hcd_unlink_urb_from_ep(hcd, urb); + unmap_urb_for_dma(hcd, urb); usbmon_urb_complete (&hcd->self, urb); usb_unanchor_urb(urb); @@ -1194,12 +1212,12 @@ void usb_hcd_endpoint_disable (struct usb_device *udev, struct usb_hcd *hcd; struct urb *urb; + might_sleep(); hcd = bus_to_hcd(udev->bus); - local_irq_disable (); /* ep is already gone from udev->ep_{in,out}[]; no more submits */ rescan: - spin_lock(&hcd_urb_list_lock); + spin_lock_irq(&hcd_urb_list_lock); list_for_each_entry (urb, &ep->urb_list, urb_list) { int tmp; int is_in; @@ -1244,13 +1262,11 @@ rescan: /* list contents may have changed */ goto rescan; } - spin_unlock(&hcd_urb_list_lock); - local_irq_enable (); + spin_unlock_irq(&hcd_urb_list_lock); /* synchronize with the hardware, so old configuration state * clears out immediately (and will be freed). */ - might_sleep (); if (hcd->driver->endpoint_disable) hcd->driver->endpoint_disable (hcd, ep); |