On Sat, 9 Jun 2007, Greg KH wrote: > > > Hm, is there any way to keep this from being in the urb entirely? > > > Shouldn't this be an internal-to-the hcd type thing? > > > > Yes, it could be done that way, I think. It'll take more work than a > > simple search-and-replace. The trickiest part is how to unlink an URB > > after it has been submitted but before it has been handed to the HCD... > > We allow that today? How, multiple threads doing the submit and then > unlink call? That's looney. We should not worry about that until after > the submit call has returned to the caller.
Sure it's looney. We still have to handle it correctly, though. Don't worry, it will be easy -- I figured out the right approach last night. Another idea suggested itself too: We could make usbcore allocate urb->hcpriv during submission instead of having each HCD do its own private allocation. It's not a big deal, just a matter of replacing several different calls to kmalloc/kfree by a single call. Any reason not to do it? Ideally, of course, each HCD would allocate its own URBs with the private area included. But we can't do that just now, since some drivers maintain pools of URBs that they use for multiple devices, potentially on different buses. > > Maybe. It _is_ documented as being private to usbcore -- but that > > might not stop people! > > Exactly, we need to make it impossible :) > > If I get the chance this week I'll look at your patch and see if we can > tweak it somehow. No, don't bother; I'll redo it completely. In the revised version there won't be a core_status field and neither usbcore nor the HCDs will use urb->status (except for the part about setting it to -EINPROGRESS when the URB is submitted and storing the status code immediately prior to calling the completion routine, for backward compatibility). Alan Stern ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
