USB: Move URB request code from usb.c to urb.c

drivers/usb/core/Makefile

@@ -2,9 +2,9 @@
 # Makefile for USB Core files and filesystem
 #
 
-export-objs	:= usb.o hcd.o
+export-objs	:= usb.o hcd.o urb.o
 
-usbcore-objs	:= usb.o usb-debug.o hub.o hcd.o
+usbcore-objs	:= usb.o usb-debug.o hub.o hcd.o urb.o
 
 ifeq ($(CONFIG_USB_DEVICEFS),y)
 	usbcore-objs	+= devio.o inode.o drivers.o devices.o

drivers/usb/core/urb.c

+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/bitops.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+
+#ifdef CONFIG_USB_DEBUG
+	#define DEBUG
+#else
+	#undef DEBUG
+#endif
+#include <linux/usb.h>
+#include "hcd.h"
+
+/**
+ * usb_alloc_urb - creates a new urb for a USB driver to use
+ * @iso_packets: number of iso packets for this urb
+ * @mem_flags: the type of memory to allocate, see kmalloc() for a list of
+ *	valid options for this.
+ *
+ * Creates an urb for the USB driver to use, initializes a few internal
+ * structures, incrementes the usage counter, and returns a pointer to it.
+ *
+ * If no memory is available, NULL is returned.
+ *
+ * If the driver want to use this urb for interrupt, control, or bulk
+ * endpoints, pass '0' as the number of iso packets.
+ *
+ * The driver must call usb_free_urb() when it is finished with the urb.
+ */
+struct urb *usb_alloc_urb(int iso_packets, int mem_flags)
+{
+	struct urb *urb;
+
+	urb = (struct urb *)kmalloc(sizeof(struct urb) + 
+		iso_packets * sizeof(struct usb_iso_packet_descriptor),
+		mem_flags);
+	if (!urb) {
+		err("alloc_urb: kmalloc failed");
+		return NULL;
+	}
+
+	memset(urb, 0, sizeof(*urb));
+	urb->count = (atomic_t)ATOMIC_INIT(1);
+	spin_lock_init(&urb->lock);
+
+	return urb;
+}
+
+/**
+ * usb_free_urb - frees the memory used by a urb when all users of it are finished
+ * @urb: pointer to the urb to free
+ *
+ * Must be called when a user of a urb is finished with it.  When the last user
+ * of the urb calls this function, the memory of the urb is freed.
+ *
+ * Note: The transfer buffer associated with the urb is not freed, that must be
+ * done elsewhere.
+ */
+void usb_free_urb(struct urb *urb)
+{
+	if (urb)
+		if (atomic_dec_and_test(&urb->count))
+			kfree(urb);
+}
+
+/**
+ * usb_get_urb - increments the reference count of the urb
+ * @urb: pointer to the urb to modify
+ *
+ * This must be  called whenever a urb is transfered from a device driver to a
+ * host controller driver.  This allows proper reference counting to happen
+ * for urbs.
+ *
+ * A pointer to the urb with the incremented reference counter is returned.
+ */
+struct urb * usb_get_urb(struct urb *urb)
+{
+	if (urb) {
+		atomic_inc(&urb->count);
+		return urb;
+	} else
+		return NULL;
+}
+		
+		
+/*-------------------------------------------------------------------*/
+
+/**
+ * usb_submit_urb - asynchronously issue a transfer request for an endpoint
+ * @urb: pointer to the urb describing the request
+ * @mem_flags: the type of memory to allocate, see kmalloc() for a list
+ *	of valid options for this.
+ *
+ * This submits a transfer request, and transfers control of the URB
+ * describing that request to the USB subsystem.  Request completion will
+ * indicated later, asynchronously, by calling the completion handler.
+ * This call may be issued in interrupt context.
+ *
+ * The caller must have correctly initialized the URB before submitting
+ * it.  Functions such as usb_fill_bulk_urb() and usb_fill_control_urb() are
+ * available to ensure that most fields are correctly initialized, for
+ * the particular kind of transfer, although they will not initialize
+ * any transfer flags.
+ *
+ * Successful submissions return 0; otherwise this routine returns a
+ * negative error number.  If the submission is successful, the complete
+ * fuction of the urb will be called when the USB host driver is
+ * finished with the urb (either a successful transmission, or some
+ * error case.)
+ *
+ * Unreserved Bandwidth Transfers:
+ *
+ * Bulk or control requests complete only once.  When the completion
+ * function is called, control of the URB is returned to the device
+ * driver which issued the request.  The completion handler may then
+ * immediately free or reuse that URB.
+ *
+ * Bulk URBs will be queued if the USB_QUEUE_BULK transfer flag is set
+ * in the URB.  This can be used to maximize bandwidth utilization by
+ * letting the USB controller start work on the next URB without any
+ * delay to report completion (scheduling and processing an interrupt)
+ * and then submit that next request.
+ *
+ * For control endpoints, the synchronous usb_control_msg() call is
+ * often used (in non-interrupt context) instead of this call.
+ *
+ * Reserved Bandwidth Transfers:
+ *
+ * Periodic URBs (interrupt or isochronous) are completed repeatedly,
+ * until the original request is aborted.  When the completion callback
+ * indicates the URB has been unlinked (with a special status code),
+ * control of that URB returns to the device driver.  Otherwise, the
+ * completion handler does not control the URB, and should not change
+ * any of its fields.
+ *
+ * Note that isochronous URBs should be submitted in a "ring" data
+ * structure (using urb->next) to ensure that they are resubmitted
+ * appropriately.
+ *
+ * If the USB subsystem can't reserve sufficient bandwidth to perform
+ * the periodic request, and bandwidth reservation is being done for
+ * this controller, submitting such a periodic request will fail.
+ *
+ * Memory Flags:
+ *
+ * General rules for how to decide which mem_flags to use:
+ * 
+ * Basically the rules are the same as for kmalloc.  There are four
+ * different possible values; GFP_KERNEL, GFP_NOFS, GFP_NOIO and
+ * GFP_ATOMIC.
+ *
+ * GFP_NOFS is not ever used, as it has not been implemented yet.
+ *
+ * There are three situations you must use GFP_ATOMIC.
+ *    a) you are inside a completion handler, an interrupt, bottom half,
+ *       tasklet or timer.
+ *    b) you are holding a spinlock or rwlock (does not apply to
+ *       semaphores)
+ *    c) current->state != TASK_RUNNING, this is the case only after
+ *       you've changed it.
+ * 
+ * GFP_NOIO is used in the block io path and error handling of storage
+ * devices.
+ *
+ * All other situations use GFP_KERNEL.
+ *
+ * Specfic rules for how to decide which mem_flags to use:
+ *
+ *    - start_xmit, timeout, and receive methods of network drivers must
+ *      use GFP_ATOMIC (spinlock)
+ *    - queuecommand methods of scsi drivers must use GFP_ATOMIC (spinlock)
+ *    - If you use a kernel thread with a network driver you must use
+ *      GFP_NOIO, unless b) or c) apply
+ *    - After you have done a down() you use GFP_KERNEL, unless b) or c)
+ *      apply or your are in a storage driver's block io path
+ *    - probe and disconnect use GFP_KERNEL unless b) or c) apply
+ *    - Changing firmware on a running storage or net device uses
+ *      GFP_NOIO, unless b) or c) apply
+ *
+ */
+int usb_submit_urb(struct urb *urb, int mem_flags)
+{
+
+	if (urb && urb->dev && urb->dev->bus && urb->dev->bus->op) {
+		if (usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe)) <= 0) {
+			err("%s: pipe %x has invalid size (<= 0)", __FUNCTION__, urb->pipe);
+			return -EMSGSIZE;
+		}
+		return urb->dev->bus->op->submit_urb(urb, mem_flags);
+	}
+	return -ENODEV;
+}
+
+/*-------------------------------------------------------------------*/
+
+/**
+ * usb_unlink_urb - abort/cancel a transfer request for an endpoint
+ * @urb: pointer to urb describing a previously submitted request
+ *
+ * This routine cancels an in-progress request.  The requests's
+ * completion handler will be called with a status code indicating
+ * that the request has been canceled, and that control of the URB
+ * has been returned to that device driver.  This is the only way
+ * to stop an interrupt transfer, so long as the device is connected.
+ *
+ * When the USB_ASYNC_UNLINK transfer flag for the URB is clear, this
+ * request is synchronous.  Success is indicated by returning zero,
+ * at which time the urb will have been unlinked,
+ * and the completion function will see status -ENOENT.  Failure is
+ * indicated by any other return value.  This mode may not be used
+ * when unlinking an urb from an interrupt context, such as a bottom
+ * half or a completion handler,
+ *
+ * When the USB_ASYNC_UNLINK transfer flag for the URB is set, this
+ * request is asynchronous.  Success is indicated by returning -EINPROGRESS,
+ * at which time the urb will normally not have been unlinked,
+ * and the completion function will see status -ECONNRESET.  Failure is
+ * indicated by any other return value.
+ */
+int usb_unlink_urb(struct urb *urb)
+{
+	if (urb && urb->dev && urb->dev->bus && urb->dev->bus->op)
+		return urb->dev->bus->op->unlink_urb(urb);
+	else
+		return -ENODEV;
+}
+
+// asynchronous request completion model
+EXPORT_SYMBOL(usb_alloc_urb);
+EXPORT_SYMBOL(usb_free_urb);
+EXPORT_SYMBOL(usb_get_urb);
+EXPORT_SYMBOL(usb_submit_urb);
+EXPORT_SYMBOL(usb_unlink_urb);
+

drivers/usb/core/usb.c

@@ -1014,219 +1014,7 @@ void usb_free_dev(struct usb_device *dev)
 	}
 }
 
-/**
- * usb_alloc_urb - creates a new urb for a USB driver to use
- * @iso_packets: number of iso packets for this urb
- * @mem_flags: the type of memory to allocate, see kmalloc() for a list of
- *	valid options for this.
- *
- * Creates an urb for the USB driver to use, initializes a few internal
- * structures, incrementes the usage counter, and returns a pointer to it.
- *
- * If no memory is available, NULL is returned.
- *
- * If the driver want to use this urb for interrupt, control, or bulk
- * endpoints, pass '0' as the number of iso packets.
- *
- * The driver must call usb_free_urb() when it is finished with the urb.
- */
-struct urb *usb_alloc_urb(int iso_packets, int mem_flags)
-{
-	struct urb *urb;
-
-	urb = (struct urb *)kmalloc(sizeof(struct urb) + 
-		iso_packets * sizeof(struct usb_iso_packet_descriptor),
-		mem_flags);
-	if (!urb) {
-		err("alloc_urb: kmalloc failed");
-		return NULL;
-	}
-
-	memset(urb, 0, sizeof(*urb));
-	urb->count = (atomic_t)ATOMIC_INIT(1);
-	spin_lock_init(&urb->lock);
-
-	return urb;
-}
-
-/**
- * usb_free_urb - frees the memory used by a urb when all users of it are finished
- * @urb: pointer to the urb to free
- *
- * Must be called when a user of a urb is finished with it.  When the last user
- * of the urb calls this function, the memory of the urb is freed.
- *
- * Note: The transfer buffer associated with the urb is not freed, that must be
- * done elsewhere.
- */
-void usb_free_urb(struct urb *urb)
-{
-	if (urb)
-		if (atomic_dec_and_test(&urb->count))
-			kfree(urb);
-}
-
-/**
- * usb_get_urb - increments the reference count of the urb
- * @urb: pointer to the urb to modify
- *
- * This must be  called whenever a urb is transfered from a device driver to a
- * host controller driver.  This allows proper reference counting to happen
- * for urbs.
- *
- * A pointer to the urb with the incremented reference counter is returned.
- */
-struct urb * usb_get_urb(struct urb *urb)
-{
-	if (urb) {
-		atomic_inc(&urb->count);
-		return urb;
-	} else
-		return NULL;
-}
-		
-		
-/*-------------------------------------------------------------------*/
-
-/**
- * usb_submit_urb - asynchronously issue a transfer request for an endpoint
- * @urb: pointer to the urb describing the request
- * @mem_flags: the type of memory to allocate, see kmalloc() for a list
- *	of valid options for this.
- *
- * This submits a transfer request, and transfers control of the URB
- * describing that request to the USB subsystem.  Request completion will
- * indicated later, asynchronously, by calling the completion handler.
- * This call may be issued in interrupt context.
- *
- * The caller must have correctly initialized the URB before submitting
- * it.  Functions such as usb_fill_bulk_urb() and usb_fill_control_urb() are
- * available to ensure that most fields are correctly initialized, for
- * the particular kind of transfer, although they will not initialize
- * any transfer flags.
- *
- * Successful submissions return 0; otherwise this routine returns a
- * negative error number.  If the submission is successful, the complete
- * fuction of the urb will be called when the USB host driver is
- * finished with the urb (either a successful transmission, or some
- * error case.)
- *
- * Unreserved Bandwidth Transfers:
- *
- * Bulk or control requests complete only once.  When the completion
- * function is called, control of the URB is returned to the device
- * driver which issued the request.  The completion handler may then
- * immediately free or reuse that URB.
- *
- * Bulk URBs will be queued if the USB_QUEUE_BULK transfer flag is set
- * in the URB.  This can be used to maximize bandwidth utilization by
- * letting the USB controller start work on the next URB without any
- * delay to report completion (scheduling and processing an interrupt)
- * and then submit that next request.
- *
- * For control endpoints, the synchronous usb_control_msg() call is
- * often used (in non-interrupt context) instead of this call.
- *
- * Reserved Bandwidth Transfers:
- *
- * Periodic URBs (interrupt or isochronous) are completed repeatedly,
- * until the original request is aborted.  When the completion callback
- * indicates the URB has been unlinked (with a special status code),
- * control of that URB returns to the device driver.  Otherwise, the
- * completion handler does not control the URB, and should not change
- * any of its fields.
- *
- * Note that isochronous URBs should be submitted in a "ring" data
- * structure (using urb->next) to ensure that they are resubmitted
- * appropriately.
- *
- * If the USB subsystem can't reserve sufficient bandwidth to perform
- * the periodic request, and bandwidth reservation is being done for
- * this controller, submitting such a periodic request will fail.
- *
- * Memory Flags:
- *
- * General rules for how to decide which mem_flags to use:
- * 
- * Basically the rules are the same as for kmalloc.  There are four
- * different possible values; GFP_KERNEL, GFP_NOFS, GFP_NOIO and
- * GFP_ATOMIC.
- *
- * GFP_NOFS is not ever used, as it has not been implemented yet.
- *
- * There are three situations you must use GFP_ATOMIC.
- *    a) you are inside a completion handler, an interrupt, bottom half,
- *       tasklet or timer.
- *    b) you are holding a spinlock or rwlock (does not apply to
- *       semaphores)
- *    c) current->state != TASK_RUNNING, this is the case only after
- *       you've changed it.
- * 
- * GFP_NOIO is used in the block io path and error handling of storage
- * devices.
- *
- * All other situations use GFP_KERNEL.
- *
- * Specfic rules for how to decide which mem_flags to use:
- *
- *    - start_xmit, timeout, and receive methods of network drivers must
- *      use GFP_ATOMIC (spinlock)
- *    - queuecommand methods of scsi drivers must use GFP_ATOMIC (spinlock)
- *    - If you use a kernel thread with a network driver you must use
- *      GFP_NOIO, unless b) or c) apply
- *    - After you have done a down() you use GFP_KERNEL, unless b) or c)
- *      apply or your are in a storage driver's block io path
- *    - probe and disconnect use GFP_KERNEL unless b) or c) apply
- *    - Changing firmware on a running storage or net device uses
- *      GFP_NOIO, unless b) or c) apply
- *
- */
-int usb_submit_urb(struct urb *urb, int mem_flags)
-{
 
-	if (urb && urb->dev && urb->dev->bus && urb->dev->bus->op) {
-		if (usb_maxpacket(urb->dev, urb->pipe, usb_pipeout(urb->pipe)) <= 0) {
-			err("%s: pipe %x has invalid size (<= 0)", __FUNCTION__, urb->pipe);
-			return -EMSGSIZE;
-		}
-		return urb->dev->bus->op->submit_urb(urb, mem_flags);
-	}
-	return -ENODEV;
-}
-
-/*-------------------------------------------------------------------*/
-
-/**
- * usb_unlink_urb - abort/cancel a transfer request for an endpoint
- * @urb: pointer to urb describing a previously submitted request
- *
- * This routine cancels an in-progress request.  The requests's
- * completion handler will be called with a status code indicating
- * that the request has been canceled, and that control of the URB
- * has been returned to that device driver.  This is the only way
- * to stop an interrupt transfer, so long as the device is connected.
- *
- * When the USB_ASYNC_UNLINK transfer flag for the URB is clear, this
- * request is synchronous.  Success is indicated by returning zero,
- * at which time the urb will have been unlinked,
- * and the completion function will see status -ENOENT.  Failure is
- * indicated by any other return value.  This mode may not be used
- * when unlinking an urb from an interrupt context, such as a bottom
- * half or a completion handler,
- *
- * When the USB_ASYNC_UNLINK transfer flag for the URB is set, this
- * request is asynchronous.  Success is indicated by returning -EINPROGRESS,
- * at which time the urb will normally not have been unlinked,
- * and the completion function will see status -ECONNRESET.  Failure is
- * indicated by any other return value.
- */
-int usb_unlink_urb(struct urb *urb)
-{
-	if (urb && urb->dev && urb->dev->bus && urb->dev->bus->op)
-		return urb->dev->bus->op->unlink_urb(urb);
-	else
-		return -ENODEV;
-}
 /*-------------------------------------------------------------------*
  *                         SYNCHRONOUS CALLS                         *
  *-------------------------------------------------------------------*/
@@ -2828,13 +2616,6 @@ EXPORT_SYMBOL(__usb_get_extra_descriptor);
 
 EXPORT_SYMBOL(usb_get_current_frame_number);
 
-// asynchronous request completion model
-EXPORT_SYMBOL(usb_alloc_urb);
-EXPORT_SYMBOL(usb_free_urb);
-EXPORT_SYMBOL(usb_get_urb);
-EXPORT_SYMBOL(usb_submit_urb);
-EXPORT_SYMBOL(usb_unlink_urb);
-
 // synchronous request completion model
 EXPORT_SYMBOL(usb_control_msg);
 EXPORT_SYMBOL(usb_bulk_msg);