Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Many files include the filename at the beginning, serveral used a wrong one.
Signed-off-by: Uwe Zeisberger <Uwe_Zeisberger@digi.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
In some places, particularly drivers and __init code, the init utsns is the
appropriate one to use. This patch replaces those with a the init_utsname
helper.
Changes: Removed several uses of init_utsname(). Hope I picked all the
right ones in net/ipv4/ipconfig.c. These are now changed to
utsname() (the per-process namespace utsname) in the previous
patch (2/7)
[akpm@osdl.org: CIFS fix]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Kirill Korotaev <dev@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Andrey Savochkin <saw@sw.ru>
Cc: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The problem with remembering a user space process by its pid is that it is
possible that the process will exit, pid wrap around will occur.
Converting to a struct pid avoid that problem, and paves the way for
implementing a pid namespace.
Also since usb is the only user of kill_proc_info_as_uid rename
kill_proc_info_as_uid to kill_pid_info_as_uid and have the new version take
a struct pid.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This is mostly included for parity with dec_nlink(), where we will have some
more hooks. This one should stay pretty darn straightforward for now.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When a filesystem decrements i_nlink to zero, it means that a write must be
performed in order to drop the inode from the filesystem.
We're shortly going to have keep filesystems from being remounted r/o between
the time that this i_nlink decrement and that write occurs.
So, add a little helper function to do the decrements. We'll tie into it in a
bit to note when i_nlink hits zero.
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch (as791b) fixes things up to avoid compiler warnings or
errors when CONFIG_USB_SUSPEND or CONFIG_PM isn't set.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Originally I didn't think any host controller driver would ever use
interrupts and polling at the same time, but it turns out ohci-hcd wants
to do exactly that. This patch (as788) makes it possible.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as787) creates a new workqueue thread to handle delayed
USB autosuspend requests. Previously the code used keventd. However
it turns out that the hub driver's suspend routine calls
flush_scheduled_work(), making it a poor candidate for running in
keventd (the call immediately deadlocks). The solution is to use a
new thread instead of keventd.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fixes kerneldoc errors on usb/core/driver.c, which occured in 2.6.18-rc6-mm2
gregkh-usb-usbcore-add-autosuspend-autoresume-infrastructure.patch
Signed-off-by: Henrik Kretzschmar <henne@nachtwindheim.de>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Implementations assume the buffer is at least 4 byte aligned.
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Somewhere along the line, a variable in a USB-OTG codepath
stopped being used; this removes the relevant compiler warning.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch(as785) forces the PM core to resume a root hub after a
power loss during system sleep. If the root hub had been suspended
before the system sleep then normally the PM core would not resume it
afterward. Without this resume, various sorts of wakeup events (like
port change events) can get lost.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The patch removes unneeded casts for the following (void *) pointers:
- struct file: private
- struct urb: context
- struct usb_bus: hcpriv
- return value of kmalloc()
The patch also contains some whitespace cleanup in the relevant areas.
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as786) removes a redundant test and fixes a problem
involving repeated system sleeps when CONFIG_USB_SUSPEND is not set.
During the first wakeup, the root hub's dev.power.power_state.event
field doesn't get updated, causing it not to be suspended during the
second sleep transition.
This takes care of the issue raised by Rafael J. Wysocki and Mattia
Dongili.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as740) removes the existing support for autosuspend of
root hubs. That support fit in rather awkwardly with the rest of
usbcore and it was used only by ohci-hcd. It won't be needed any more
since the hub driver will take care of autosuspending all hubs, root
or external.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as741) makes the non-hub parts of usbcore actually use the
autosuspend facilities added by an earlier patch.
Devices opened through usbfs are autoresumed and then
autosuspended upon close.
Likewise for usb-skeleton.
Devices are autoresumed for usb_set_configuration.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as739) adds the basic infrastructure for USB autosuspend
and autoresume. The main features are:
PM usage counters added to struct usb_device and struct
usb_interface, indicating whether it's okay to autosuspend
them or they are currently in use.
Flag added to usb_device indicating whether the current
suspend/resume operation originated from outside or as an
autosuspend/autoresume.
Flag added to usb_driver indicating whether the driver
supports autosuspend. If not, no device bound to the driver
will be autosuspended.
Mutex added to usb_device for protecting PM operations.
Unlike the device semaphore, the locking rule for the pm_mutex
is that you must acquire the locks going _up_ the device tree.
New routines handling autosuspend/autoresume requests for
interfaces and devices.
Suspend and resume requests are propagated up the device tree
(but not outside the USB subsystem).
work_struct added to usb_device, for carrying out delayed
autosuspend requests.
Autoresume added (and autosuspend prevented) during probe and
disconnect.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as778) adds a field to struct usb_device to store the
device's level in the USB tree. In itself this number isn't really
important. But the overhead is very low, and in a later patch it will
be used for preventing bogus warnings from the lockdep checker.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As part of the ongoing program to flatten out the HCD bus-glue layer,
this patch (as771b) eliminates the hcpriv, release, and kref fields
from struct usb_bus. hcpriv and release were not being used for
anything worthwhile, and kref has been moved into the enclosing
usb_hcd structure.
Along with those changes, the patch gets rid of usb_bus_get and
usb_bus_put, replacing them with usb_get_hcd and usb_put_hcd.
The one interesting aspect is that the dev_set_drvdata call was
removed from usb_put_hcd, where it clearly doesn't belong. This means
the driver private data won't get reset to NULL. It shouldn't cause
any problems, since the private data is undefined when no driver is
bound.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as770b) introduces a new field to usb_bus: a flag
indicating whether or not the host controller uses DMA. This serves
to encapsulate the computation. It also means we will have only one
spot to update if the DMA API changes.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
All of the currently-supported USB host controller drivers use the HCD
bus-glue framework. As part of the program for flattening out the glue
layer, this patch (as769) removes the usb_operations structure. All
function calls now go directly to the HCD routines (slightly renamed
to remain within the "usb_" namespace).
The patch also removes usb_alloc_bus(), because it's not useful in the
HCD framework and it wasn't referenced anywhere.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/usb/core/hub.c: In function `hub_events':
drivers/usb/core/hub.c:2591: warning: statement with no effect
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
It's generally a bad idea for USB interface drivers to try to change a
device's configuration, and usbcore doesn't provide any way for them
to do it. However in a few exceptional circumstances it can make
sense. This patch (as767) adds a roundabout mechanism to help drivers
that may need it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch marks some USB core's functions parameters as const. This
improves the design (we're saying to the caller that its parameter is
not going to be modified) and may help in compiler's optimisation work.
Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
New code being pushed to linuxuwb.org requires this patch to connect
WUSB devices.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch teaches the USB stack handling of WUSB devices (those whose
speed is USB_SPEED_VARIABLE). For these devices, we need to set ep0's
maxpacketsize to 512 (even though the device descriptor reports it as
0xff).
New code being pushed to linuxuwb.org requires this patch to connect WUSB
devices.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch enables the USB stack to recognize WUSB devices (from a
WUSB HCD) and assigns them the proper speed setting
(USB_SPEED_VARIABLE).
1. Introduce usb_hcd->wireless to mark a host controller instance as
being wireless, and thus having wireless 'fake' ports.
[discarded previous model of using a reserved bit in the port_stat
struct to do this; thanks to Alan Stern for indicating the
proper way to do it].
2. Introduce hub.c:hub_is_wusb() that tests if a hub is a WUSB root
hub (WUSB doesn't have non-root hubs).
New code being pushed to linuxuwb.org requires this patch to connect WUSB
devices.
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Change usb_get_configuration() so that it is more tolerant to devices
with bad configuration descriptors (it'll make it ignore
configurations that fail to load).
Signed-off-by: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We don't want khubd to start interfering in the device-resume process
merely because the PORT_STATUS_C_SUSPEND feature happens to be set.
Ports need to be marked as busy while a resume is taking place.
In addition, so long as ports are marked as busy, khubd won't be able to
clear their various status-change features. On an interrupt-driven root
hub this could lead to an interrupt storm. Root hub IRQs should not be
re-enabled until the busy_bits value is equal to 0.
This patch (as765) fixes these two potential problems.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The inconsistent lock state problem in usbcore (the one that shows up
when an HCD is unloaded) comes down to two inter-related problems:
usb_rh_urb_dequeue() isn't set up to be called with interrupts
disabled.
hcd_endpoint_disable() doesn't wait for all URBs on the
endpoint's queue to complete.
The two problems are related because the one type of URB that isn't
likely to be complete when hcd_endpoint_disable() returns is a root-hub
URB. Right now usb_rh_urb_dequeue() waits for them to complete, and it
assumes interrupts are enabled so it can wait. But
hcd_endpoint_disable() calls it with interrupts disabled.
Now, it should be legal to unlink root-hub URBs with interrupts
disabled. The solution is to move the waiting into
hcd_endpoint_disable(), where it belongs. This patch (as754) does that.
It turns out to be completely safe to replace the del_timer_sync() with
a simple del_timer(). It doesn't matter if the timer routine is
running; hcd_root_hub_lock will synchronize the two threads and the
status URB will complete with an unlink error, as it should.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If some problem occurs during ehci startup, for instance, request_irq fails,
echi hcd driver tries it best to cleanup, but fails to unregister reboot
notifier, which in turn leads to crash on reboot/poweroff.
The following patch resolves this problem by not using reboot notifiers
anymore, but instead making ehci/ohci driver get its own shutdown method. For
PCI, it is done through pci glue, for everything else through platform driver
glue.
One downside: sa1111 does not use platform driver stuff, and does not have its
own shutdown hook, so no 'shutdown' is called for it now. I'm not sure if it
is really necessary on that platform, though.
Signed-off-by: Aleks Gorelov <dared1st@yahoo.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
These functions makes USB driver's code simpler when dealing with endpoints
by avoiding them from accessing the endpoint's descriptor structure directly
when they only need to know the endpoint's transfer type and/or
direction.
Please, read each functions' documentation in order to know how to use
them.
Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Making structs const prevents accidental bugs and with the proper debug
options they're protected against corruption.
Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch uses completion timeout instead of a timer to implement
a timeout when submitting an URB in usb_start_wait_urb().
It also fixes a small issue. With the previous code, if no timeout
happened and the URB's status was set to ECONNRESET value, the code
assumed wrongly that a timeout had occured.
Signed-off-by: Franck Bui-Huu <vagabon.xyz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as736) makes the hub driver more readable by improving the
usage of "#ifdef CONFIG_PM" and "#ifdef CONFIG_USB_SUSPEND".
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since usb_generic can be unbound from a USB device, we need to be able
to handle the possibility that a suspend or resume request arrives for a
device with no driver. This patch (as735) arranges things so that
resume requests will fail and suspend requests will use the standard USB
port-suspend code. Attempts to suspend or resume an unbound interface
are handled similarly (although the error caused by trying to resume an
unbound interface is dropped by the calling routine).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as734) rationalizes the various tests of device state and
power states. There are duplications and mistaken tests in several
places.
Perhaps the most interesting challenge is where the hub driver tests to
see that all the child devices are suspended before allowing itself to
be suspended. When CONFIG_USB_SUSPEND is set the test is
straightforward, since we expect that the children _will_ be suspended.
But when CONFIG_USB_SUSPEND isn't set, it's not so clear what should be
done. The code compromises by checking the child's
power.power_state.event field.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as733) fixes up the places where device states and power
states are set in usbcore. Right now things are duplicated or missing;
this should straighten things out.
The idea is that udev->state is USB_STATE_SUSPENDED exactly when the
device's upstream port has been suspended, whereas
udev->dev.power.power_state.event reflects the result of the last call
to the suspend/resume routines (which might not actually change the
device state, especially if CONFIG_USB_SUSPEND isn't set).
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Currently we rely on intf->dev.power.power_state.event for tracking
whether intf is suspended. This is not a reliable technique because
that value is owned by the PM core, not by usbcore. This patch (as718b)
adds a new flag so that we can accurately tell which interfaces are
suspended and which aren't.
At first one might think these flags aren't needed, since interfaces
will be suspended along with their devices. It turns out there are a
couple of intermediate situations where that's not quite true, such as
while processing a remote-wakeup request.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as717b) removes the existing recursion in hub resume code:
Resuming a hub will no longer automatically resume the devices attached
to the hub.
At the same time, it adds one level of recursion: Suspending a USB
device will automatically suspend all the device's interfaces. Failure
at an intermediate stage will cause all the already-suspended interfaces
to be resumed. Attempts to suspend or resume an interface by itself will
do nothing, although they won't return an error. Thus the regular
system-suspend and system-resume procedures should continue to work as
before; only runtime PM will be affected.
The patch also removes the code that tests state of the interfaces
before suspending a device. It's no longer needed, since everything
gets suspended together.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as716b) splits up the core suspend and resume routines into
two parts each: one for handling devices and one for handling
interfaces. The behavior of the parts should be the same as in the old
unified code.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as714b) makes usb_generic into a usb_device_driver capable
of being probed and unbound, just like other drivers. A fair amount of
the work that used to get done during discovery or removal of a USB
device have been moved to the probe and disconnect methods of
usb_generic: creating the sysfs attributes and selecting an initial
configuration. However the normal behavior should continue to be the
same as before.
We will now have the possibility of creating other USB device drivers,
They will assist with exporting devices to remote systems
(USB-over-TCPIP) or to paravirtual guest operating systems.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as732) adds a usb_device_driver structure, for representing
drivers that manage an entire USB device as opposed to just an
interface. Support routines like usb_register_device_driver,
usb_deregister_device_driver, usb_probe_device, and usb_unbind_device
are also added.
Unlike an earlier version of this patch, the new code is type-safe. To
accomplish this, the existing struct driver embedded in struct
usb_driver had to be wrapped in an intermediate wrapper. This enables
the core to tell at runtime whether a particular struct driver belongs
to a device driver or to an interface driver.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This revised patch (as713b) moves a few routines among source files in
usbcore. Some driver-related code in usb.c (claiming interfaces and
matching IDs) is moved to driver.c, where it belongs. Also the
usb_generic stuff in driver.c is moved to a new source file: generic.c.
(That's the reason for revising the patch.) Although not very big now,
it will get bigger in a later patch.
None of the code has been changed; it has only been re-arranged.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Al Viro