linux.git/drivers/usb/core/devio.c, branch v2.6.29

USB: usbfs: keep async URBs until the device file is closed

2009-03-17T21:01:28+00:00

The usbfs driver manages a list of completed asynchronous URBs.  But
it is too eager to free the entries on this list: destroy_async() gets
called whenever an interface is unbound or a device is removed, and it
deallocates the outstanding struct async entries for all URBs on that
interface or device.  This is wrong; the user program should be able
to reap an URB any time after it has completed, regardless of whether
or not the interface is still bound or the device is still present.

This patch (as1222) moves the code for deallocating the completed list
entries from destroy_async() to usbdev_release().  The outstanding
entries won't be freed until the user program has closed the device
file, thereby eliminating any possibility that the remaining URBs
might still be reaped.

This fixes a bug in which a program can hang in the USBDEVFS_REAPURB
ioctl when the device is unplugged.

Reported-and-tested-by: Martin Poupe 
Signed-off-by: Alan Stern 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

USB: fix char-device disconnect handling

2009-01-28T00:15:32+00:00

This patch (as1198) fixes a conceptual bug: Somewhere along the line
we managed to confuse USB class devices with USB char devices.  As a
result, the code to send a disconnect signal to userspace would not be
built if both CONFIG_USB_DEVICE_CLASS and CONFIG_USB_DEVICEFS were
disabled.

The usb_fs_classdev_common_remove() routine has been renamed to
usbdev_remove() and it is now called whenever any USB device is
removed, not just when a class device is unregistered.  The notifier
registration and unregistration calls are no longer conditionally
compiled.  And since the common removal code will always be called as
part of the char device interface, there's no need to call it again as
part of the usbfs interface; thus the invocation of
usb_fs_classdev_common_remove() has been taken out of
usbfs_remove_device().

Signed-off-by: Alan Stern 
Reported-by: Alon Bar-Lev 
Tested-by: Alon Bar-Lev 
Cc: stable

USB: fix minor nit in usbfs checking

2009-01-07T18:00:13+00:00

One minor nit did show up, though.  The patch below
seems to make more sense than the code does without it.

Signed-off-by: Mark Lord 
Signed-off-by: Greg Kroah-Hartman

USB: Remove restrictions on signal numbers in devio.c

2009-01-07T17:59:51+00:00

Just over a year ago (!) I had this brief exchange with Alan Stern:

>> It seems that the signal that can be used with USBDEVFS_DISCSIGNAL and 
>> in usbdevfs_urb.signr is limited to the real-time signals SIGRTMIN to 
>> SIGRTMAX. What's the rationale for this restriction? I believe that a 
>> process can kill() itself with any signal number, can't it? I was 
>> planning to use SIGIO for usbdevfs_urb.signr and SIGTERM (uncaught) for 
>> USBDEVFS_DISCSIGNAL. I don't think I'll have a problem with using 
>> SIGRTMIN+n instead, but I'm curious to know if there's some subtle 
>> problem with the non-real-time signals that I should be aware of.
>
> I don't know of any reason for this restriction.

Since no-one else could think of a reason either, I offer the following 
patch which allows any signal to be used with USBDEVFS_DISCSIGNAL and 
usbdevfs_urb.signr.

Signed-off-by: Phil Endecott 
Cc: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

CRED: Wrap current->cred and a few other accessors

2008-11-13T23:39:18+00:00

Wrap current->cred and a few other accessors to hide their actual
implementation.

Signed-off-by: David Howells 
Acked-by: James Morris 
Acked-by: Serge Hallyn 
Signed-off-by: James Morris

CRED: Wrap task credential accesses in the USB driver

2008-11-13T23:38:43+00:00

Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells 
Reviewed-by: James Morris 
Acked-by: Serge Hallyn 
Cc: Greg Kroah-Hartman 
Cc: linux-usb@vger.kernel.org
Signed-off-by: James Morris

USB: remove err() macro from usb core code

2008-10-17T21:41:11+00:00

USB should not be having it's own printk macros, so remove err() and
use the system-wide standard of dev_err() wherever possible.  In the
few places that will not work out, use a basic printk().

Signed-off-by: Greg Kroah-Hartman

USB: remove warn() macro from usb drivers

2008-10-17T21:41:09+00:00

USB should not be having it's own printk macros, so remove warn() and
use the system-wide standard of dev_warn() wherever possible.  In the
few places that will not work out, use a basic printk().

Signed-off-by: Greg Kroah-Hartman

USB: snoop processes opening usbfs device files

2008-10-17T21:41:03+00:00

This patch (as1148) adds a new "snoop" message to usbfs when a device
file is opened, identifying the process responsible.  This comes in
extremely handy when trying to determine which program is doing some
unwanted USB access.

Signed-off-by: Alan Stern 
Signed-off-by: Greg Kroah-Hartman

device create: usb: convert device_create_drvdata to device_create

2008-10-16T16:24:45+00:00

Now that device_create() has been audited, rename things back to the
original call to be sane.

Signed-off-by: Greg Kroah-Hartman