linux/drivers/usb
Kent Overstreet 0460fef2a9 aio: use cancellation list lazily
Cancelling kiocbs requires adding them to a per kioctx linked list,
which is one of the few things we need to take the kioctx lock for in
the fast path.  But most kiocbs can't be cancelled - so if we just do
this lazily, we can avoid quite a bit of locking overhead.

While we're at it, instead of using a flag bit switch to using ki_cancel
itself to indicate that a kiocb has been cancelled/completed.  This lets
us get rid of ki_flags entirely.

[akpm@linux-foundation.org: remove buggy BUG()]
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 18:38:29 -07:00
..
atm usbatm: fix potential NULL pointer dereference 2013-04-19 10:20:41 -07:00
c67x00 usb: c67x00 RetryCnt value in c67x00 TD should be 3 2013-03-07 12:31:37 +08:00
chipidea usb: patches for v3.10 merge window 2013-04-05 15:18:00 -07:00
class Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2013-05-01 13:20:04 -07:00
core USB patches for 3.10-rc1 2013-04-29 12:19:23 -07:00
dwc3 usb: dwc3: add CONFIG_PM_SLEEP to suspend/resume functions 2013-04-02 11:42:51 +03:00
early fix build of EHCI debug port code when USB_CHIPIDEA but !USB_EHCI_HCD 2012-11-02 10:13:33 -07:00
gadget aio: use cancellation list lazily 2013-05-07 18:38:29 -07:00
host ARM: arm-soc cleanup for 3.10 2013-05-02 09:03:55 -07:00
image USB: regroup all depends on USB within an if USB block 2013-04-09 16:49:07 -07:00
misc Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
mon USB: regroup all depends on USB within an if USB block 2013-04-09 16:49:07 -07:00
musb USB: regroup all depends on USB within an if USB block 2013-04-09 16:49:07 -07:00
phy USB: OMAP: ISP1301 needs USB_PHY 2013-04-25 10:58:00 -07:00
renesas_usbhs USB: regroup all depends on USB within an if USB block 2013-04-09 16:49:07 -07:00
serial USB patches for 3.10-rc1 2013-04-29 12:19:23 -07:00
storage Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-05-01 17:51:54 -07:00
wusbcore USB: regroup all depends on USB within an if USB block 2013-04-09 16:49:07 -07:00
Kconfig USB: regroup all depends on USB within an if USB block 2013-04-09 16:49:07 -07:00
Makefile usb: phy: remove CONFIG_USB_OTG_UTILS 2013-03-18 11:18:08 +02:00
README
usb-common.c usb: otg: move usb_otg_state_string to usb-common.c 2013-03-18 11:18:03 +02:00
usb-skeleton.c USB: usb-skeleton.c: fix blocked forever in skel_read 2013-03-25 13:32:20 -07:00

To understand all the Linux-USB framework, you'll use these resources:

    * This source code.  This is necessarily an evolving work, and
      includes kerneldoc that should help you get a current overview.
      ("make pdfdocs", and then look at "usb.pdf" for host side and
      "gadget.pdf" for peripheral side.)  Also, Documentation/usb has
      more information.

    * The USB 2.0 specification (from www.usb.org), with supplements
      such as those for USB OTG and the various device classes.
      The USB specification has a good overview chapter, and USB
      peripherals conform to the widely known "Chapter 9".

    * Chip specifications for USB controllers.  Examples include
      host controllers (on PCs, servers, and more); peripheral
      controllers (in devices with Linux firmware, like printers or
      cell phones); and hard-wired peripherals like Ethernet adapters.

    * Specifications for other protocols implemented by USB peripheral
      functions.  Some are vendor-specific; others are vendor-neutral
      but just standardized outside of the www.usb.org team.

Here is a list of what each subdirectory here is, and what is contained in
them.

core/		- This is for the core USB host code, including the
		  usbfs files and the hub class driver ("khubd").

host/		- This is for USB host controller drivers.  This
		  includes UHCI, OHCI, EHCI, and others that might
		  be used with more specialized "embedded" systems.

gadget/		- This is for USB peripheral controller drivers and
		  the various gadget drivers which talk to them.


Individual USB driver directories.  A new driver should be added to the
first subdirectory in the list below that it fits into.

image/		- This is for still image drivers, like scanners or
		  digital cameras.
../input/	- This is for any driver that uses the input subsystem,
		  like keyboard, mice, touchscreens, tablets, etc.
../media/	- This is for multimedia drivers, like video cameras,
		  radios, and any other drivers that talk to the v4l
		  subsystem.
../net/		- This is for network drivers.
serial/		- This is for USB to serial drivers.
storage/	- This is for USB mass-storage drivers.
class/		- This is for all USB device drivers that do not fit
		  into any of the above categories, and work for a range
		  of USB Class specified devices. 
misc/		- This is for all USB device drivers that do not fit
		  into any of the above categories.