Commit a707e953 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman

usb core:

	- initial add of the "int mem_flags" call to the usb_submit_urb() call
parent 040fdeaf
...@@ -1148,6 +1148,7 @@ struct urb * usb_get_urb(struct urb *urb) ...@@ -1148,6 +1148,7 @@ struct urb * usb_get_urb(struct urb *urb)
/** /**
* usb_submit_urb - asynchronously issue a transfer request for an endpoint * usb_submit_urb - asynchronously issue a transfer request for an endpoint
* @urb: pointer to the urb describing the request * @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 * This submits a transfer request, and transfers control of the URB
* describing that request to the USB subsystem. Request completion will * describing that request to the USB subsystem. Request completion will
...@@ -1198,11 +1199,48 @@ struct urb * usb_get_urb(struct urb *urb) ...@@ -1198,11 +1199,48 @@ struct urb * usb_get_urb(struct urb *urb)
* If the USB subsystem can't reserve sufficient bandwidth to perform * If the USB subsystem can't reserve sufficient bandwidth to perform
* the periodic request, and bandwidth reservation is being done for * the periodic request, and bandwidth reservation is being done for
* this controller, submitting such a periodic request will fail. * 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 usb_submit_urb(struct urb *urb, int mem_flags)
{ {
if (urb && urb->dev && urb->dev->bus && urb->dev->bus->op) if (urb && urb->dev && urb->dev->bus && urb->dev->bus->op)
return urb->dev->bus->op->submit_urb(urb); return urb->dev->bus->op->submit_urb(urb, mem_flags);
else else
return -ENODEV; return -ENODEV;
} }
...@@ -1272,7 +1310,7 @@ static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length) ...@@ -1272,7 +1310,7 @@ static int usb_start_wait_urb(struct urb *urb, int timeout, int* actual_length)
add_wait_queue(&awd.wqh, &wait); add_wait_queue(&awd.wqh, &wait);
urb->context = &awd; urb->context = &awd;
status = usb_submit_urb(urb); status = usb_submit_urb(urb, GFP_KERNEL);
if (status) { if (status) {
// something went wrong // something went wrong
usb_free_urb(urb); usb_free_urb(urb);
......
...@@ -857,7 +857,7 @@ extern struct urb *usb_alloc_urb(int iso_packets); ...@@ -857,7 +857,7 @@ extern struct urb *usb_alloc_urb(int iso_packets);
extern void usb_free_urb(struct urb *urb); extern void usb_free_urb(struct urb *urb);
#define usb_put_urb usb_free_urb #define usb_put_urb usb_free_urb
extern struct urb *usb_get_urb(struct urb *urb); extern struct urb *usb_get_urb(struct urb *urb);
extern int usb_submit_urb(struct urb *urb); extern int usb_submit_urb(struct urb *urb, int mem_flags);
extern int usb_unlink_urb(struct urb *urb); extern int usb_unlink_urb(struct urb *urb);
/*-------------------------------------------------------------------* /*-------------------------------------------------------------------*
...@@ -906,7 +906,7 @@ struct usb_operations { ...@@ -906,7 +906,7 @@ struct usb_operations {
int (*allocate)(struct usb_device *); int (*allocate)(struct usb_device *);
int (*deallocate)(struct usb_device *); int (*deallocate)(struct usb_device *);
int (*get_frame_number) (struct usb_device *usb_dev); int (*get_frame_number) (struct usb_device *usb_dev);
int (*submit_urb) (struct urb *urb); int (*submit_urb) (struct urb *urb, int mem_flags);
int (*unlink_urb) (struct urb *urb); int (*unlink_urb) (struct urb *urb);
}; };
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment