History log of /linux-master/drivers/parisc/led.c
Revision Date Author Comments
# 26dd4878 08-Mar-2024 Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

parisc: led: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Helge Deller <deller@gmx.de>


# 789e527a 27-Aug-2023 Helge Deller <deller@gmx.de>

parisc: led: Rewrite LED/LCD driver to utilizize Linux LED subsystem

Rewrite the whole driver and drop the own code to calculate load
average, disk and LAN load. Switch instead to use the in-kernel LED
subsystem, which gives us quite some advantages, e.g.
- existing triggers for heartbeat and disk/lan activity can be used
- users can configre the LEDs at will to any existing trigger via
/sys/class/leds
- less overhead since we don't need to run own timers
- fully integrated in Linux and as such cleaner code.

Note that the driver now depends on CONFIG_LEDS_CLASS which has to
be built-in and not as module.

Signed-off-by: Helge Deller <deller@gmx.de>


# 3b425dd2 27-Aug-2023 Helge Deller <deller@gmx.de>

parisc: led: Move register_led_regions() to late_initcall()

Signed-off-by: Helge Deller <deller@gmx.de>


# 358ad816 25-Aug-2023 Helge Deller <deller@gmx.de>

parisc: led: Reduce CPU overhead for disk & lan LED computation

Older PA-RISC machines have LEDs which show the disk- and LAN-activity.
The computation is done in software and takes quite some time, e.g. on a
J6500 this may take up to 60% time of one CPU if the machine is loaded
via network traffic.

Since most people don't care about the LEDs, start with LEDs disabled and
just show a CPU heartbeat LED. The disk and LAN LEDs can be turned on
manually via /proc/pdc/led.

Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>


# 41f563ab 16-Nov-2022 Shang XiaoJing <shangxiaojing@huawei.com>

parisc: led: Fix potential null-ptr-deref in start_task()

start_task() calls create_singlethread_workqueue() and not checked the
ret value, which may return NULL. And a null-ptr-deref may happen:

start_task()
create_singlethread_workqueue() # failed, led_wq is NULL
queue_delayed_work()
queue_delayed_work_on()
__queue_delayed_work() # warning here, but continue
__queue_work() # access wq->flags, null-ptr-deref

Check the ret value and return -ENOMEM if it is NULL.

Fixes: 3499495205a6 ("[PARISC] Use work queue in LED/LCD driver instead of tasklet.")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>


# 4cb26436 18-Aug-2022 Wolfram Sang <wsa+renesas@sang-engineering.com>

parisc: led: Move from strlcpy with unused retval to strscpy

Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Helge Deller <deller@gmx.de>


# 359745d7 21-Jan-2022 Muchun Song <songmuchun@bytedance.com>

proc: remove PDE_DATA() completely

Remove PDE_DATA() completely and replace it with pde_data().

[akpm@linux-foundation.org: fix naming clash in drivers/nubus/proc.c]
[akpm@linux-foundation.org: now fix it properly]

Link: https://lkml.kernel.org/r/20211124081956.87711-2-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 7e07b747 26-Jun-2021 Jinchao Wang <wjc@cdjrlc.com>

parisc: Replace symbolic permissions with octal permissions

Resolve following checkpatch issue,
Replace symbolic permissions with octal permissions

Signed-off-by: Jinchao Wang <wjc@cdjrlc.com>
Signed-off-by: Helge Deller <deller@gmx.de>


# 97a32539 03-Feb-2020 Alexey Dobriyan <adobriyan@gmail.com>

proc: convert everything to "struct proc_ops"

The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

llseek => proc_lseek
unlocked_ioctl => proc_ioctl

xxx => proc_xxx

delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 2874c5fd 27-May-2019 Thomas Gleixner <tglx@linutronix.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>


# b4387490 01-Apr-2019 Helge Deller <deller@gmx.de>

parisc: Skip registering LED when running in QEMU

No need to spend CPU cycles when we run on QEMU.

Signed-off-by: Helge Deller <deller@gmx.de>
CC: stable@vger.kernel.org # v4.9+


# 2d76978d 04-Mar-2018 Helge Deller <deller@gmx.de>

parisc/led: Fix sparse warnings

Annotate user buffer and use NULL to avoid sparse warnings.

Signed-off-by: Helge Deller <deller@gmx.de>


# 7c0f6ba6 24-Dec-2016 Linus Torvalds <torvalds@linux-foundation.org>

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# d9dda78b 31-Mar-2013 Al Viro <viro@zeniv.linux.org.uk>

procfs: new helper - PDE_DATA(inode)

The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data. Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>


# 496ad9aa 23-Jan-2013 Al Viro <viro@zeniv.linux.org.uk>

new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>


# 79a04296 06-Nov-2010 Guy Martin <gmsoft@tuxicoman.be>

parisc: KittyHawk LCD fix

K class aka KittyHawk don't have LED support on their LCD. Installing
HP-UX confirmed this. The current led_wq fills the LCD with black
characters each time it runs.

The patch prevents the led_wq workqueue and its proc entry to be
created for KittyHawk machines.

It also increase min_cmd_delay as currently, one character out of two
is lost when a string is sent to the LCD.

Signed-off-by: Guy Martin <gmsoft@tuxicoman.be>
Signed-off-by: Kyle McMartin <kyle@mcmartin.c>


# c442ef96 27-Sep-2010 Kyle McMartin <kyle@dreadnought.i.jkkm.org>

parisc: squelch warning when using dev_get_stats

And switch to struct rtnl_link_stats64...

Signed-off-by: Kyle McMartin <kyle@redhat.com>


# 4b4fd27c 02-Aug-2010 Helge Deller <deller@gmx.de>

PARISC: led.c - fix potential stack overflow in led_proc_write()

avoid potential stack overflow by correctly checking count parameter

Reported-by: Ilja <ilja@netric.org>
Signed-off-by: Helge Deller <deller@gmx.de>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 28172739 07-Jul-2010 Eric Dumazet <eric.dumazet@gmail.com>

net: fix 64 bit counters on 32 bit arches

There is a small possibility that a reader gets incorrect values on 32
bit arches. SNMP applications could catch incorrect counters when a
32bit high part is changed by another stats consumer/provider.

One way to solve this is to add a rtnl_link_stats64 param to all
ndo_get_stats64() methods, and also add such a parameter to
dev_get_stats().

Rule is that we are not allowed to use dev->stats64 as a temporary
storage for 64bit stats, but a caller provided area (usually on stack)

Old drivers (only providing get_stats() method) need no changes.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>


# 217bfb51 26-Nov-2009 Alexey Dobriyan <adobriyan@gmail.com>

parisc: convert /proc/pdc/{lcd,led} to seq_file

Convert code away from ->read_proc/->write_proc interfaces.
Switch to proc_create()/proc_create_data() which make addition of
proc entries reliable wrt NULL ->proc_fops, NULL ->data and so on.

Problem with ->read_proc et al is described here
commit 786d7e1612f0b0adb6046f19b906609e4fe8b1ba
"Fix rmmod/read/write races in /proc entries"

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>


# 246c65ad 09-Nov-2009 Eric Dumazet <eric.dumazet@gmail.com>

parisc: led: Use for_each_netdev_rcu()

Use for_each_netdev_rcu() and dont lock dev_base_lock anymore

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>


# 1ab2eaa2 20-Mar-2009 Alexander Beregalov <a.beregalov@gmail.com>

parisc: led: remove proc_dir_entry::owner

proc_dir_entry::owner was removed in 0702c1c1a4
(proc 2/2: remove struct proc_dir_entry::owner)

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>


# 8a1def45 06-Jan-2009 Helge Deller <deller@gmx.de>

parisc: blink all or loadavg LEDs on oops

- depending on machine type, blink all leds or just the loadavg
leds twice a second on oops.
- cancel_rearming_delayed_workqueue() is obsolete,
use cancel_delayed_work_sync() instead

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>


# eeda3fd6 19-Nov-2008 Stephen Hemminger <shemminger@vyatta.com>

netdev: introduce dev_get_stats()

In order for the network device ops get_stats call to be immutable, the handling
of the default internal network device stats block has to be changed. Add a new
helper function which replaces the old use of internal_get_stats.

Note: change return code to make it clear that the caller should not
go changing the returned statistics.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>


# a8043ecb 14-May-2008 Harvey Harrison <harvey.harrison@gmail.com>

drivers/parisc: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Grant Grundler <grundler@parisc-linux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>


# 17159b0b 16-Dec-2007 Joe Perches <joe@perches.com>

[PARISC]: Fix build after ipv4_is_*() changes.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>


# 881d966b 17-Sep-2007 Eric W. Biederman <ebiederm@xmission.com>

[NET]: Make the device list and device lookups per namespace.

This patch makes most of the generic device layer network
namespace safe. This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables. The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces. The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace. This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change. Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>


# d2f1c0fa 18-Jun-2007 Julian Stecklina <der_julian@web.de>

[PARISC] stop lcd driver from stripping initial whitespace

Signed-off-by: Julian Stecklina <der_julian@web.de>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>


# 7562f876 03-May-2007 Pavel Emelianov <xemul@openvz.org>

[NET]: Rework dev_base via list_head (v3)

Cleanup of dev_base list use, with the aim to simplify making device
list per-namespace. In almost every occasion, use of dev_base variable
and dev->next pointer could be easily replaced by for_each_netdev
loop. A few most complicated places were converted to using
first_netdev()/next_netdev().

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>


# 5a1b5898 28-Apr-2007 Rusty Russell <rusty@rustcorp.com.au>

[NET]: Remove NETIF_F_INTERNAL_STATS, default to internal stats.

Herbert Xu conviced me that a new flag was overkill; every driver
currently overrides get_stats, so we might as well make the internal
one the default. If someone did fail to set get_stats, they would now
get all 0 stats instead of "No statistics available".

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>


# c45d286e 28-Mar-2007 Rusty Russell <rusty@rustcorp.com.au>

[NET]: Inline net_device_stats

Network drivers which keep stats allocate their own stats structure
then write a get_stats() function to return them. It would be nice if
this were done by default.

1) Add a new "stats" field to "struct net_device".
2) Add a new feature field to say "this driver uses the internal one"
3) Have a default "get_stats" which returns NULL if that feature not set.
4) Change callers to check result of get_stats call for NULL, not if
->get_stats is set.

This should not break backwards compatibility with older drivers, yet
allow modern drivers to shed some boilerplate code.

Lightly tested: works for a modified lguest network driver.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>


# 6e16d940 07-Jan-2007 Helge Deller <deller@gmx.de>

[PARISC] Convert soft power switch driver to kthread

And remove it's reference in time.c.
Allow lcd_print() to take a const char *.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>


# b653d081 10-Feb-2007 Alexey Dobriyan <adobriyan@gmail.com>

[PATCH] proc: remove useless (and buggy) ->nlink settings

Bug: pnx8550 code creates directory but resets ->nlink to 1.

create_proc_entry() et al will correctly set ->nlink for you.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Corey Minyard <minyard@acm.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>


# 6858f3bf 07-Dec-2006 David Howells <dhowells@redhat.com>

[PATCH] WorkStruct: Fix up some PA-RISC work items

Fix up some PA-RISC work items broken by the workstruct reduction.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>


# 96b644bd 02-Oct-2006 Serge E. Hallyn <serue@us.ibm.com>

[PATCH] namespaces: utsname: use init_utsname when appropriate

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>


# f8891e5e 30-Jun-2006 Christoph Lameter <clameter@sgi.com>

[PATCH] Light weight event counters

The remaining counters in page_state after the zoned VM counter patches
have been applied are all just for show in /proc/vmstat. They have no
essential function for the VM.

We use a simple increment of per cpu variables. In order to avoid the most
severe races we disable preempt. Preempt does not prevent the race between
an increment and an interrupt handler incrementing the same statistics
counter. However, that race is exceedingly rare, we may only loose one
increment or so and there is no requirement (at least not in kernel) that
the vm event counters have to be accurate.

In the non preempt case this results in a simple increment for each
counter. For many architectures this will be reduced by the compiler to a
single instruction. This single instruction is atomic for i386 and x86_64.
And therefore even the rare race condition in an interrupt is avoided for
both architectures in most cases.

The patchset also adds an off switch for embedded systems that allows a
building of linux kernels without these counters.

The implementation of these counters is through inline code that hopefully
results in only a single instruction increment instruction being emitted
(i386, x86_64) or in the increment being hidden though instruction
concurrency (EPIC architectures such as ia64 can get that done).

Benefits:
- VM event counter operations usually reduce to a single inline instruction
on i386 and x86_64.
- No interrupt disable, only preempt disable for the preempt case.
Preempt disable can also be avoided by moving the counter into a spinlock.
- Handling is similar to zoned VM counters.
- Simple and easily extendable.
- Can be omitted to reduce memory use for embedded use.

References:

RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=113512330605497&w=2
RFC http://marc.theaimsgroup.com/?l=linux-kernel&m=114988082814934&w=2
local_t http://marc.theaimsgroup.com/?l=linux-kernel&m=114991748606690&w=2
V2 http://marc.theaimsgroup.com/?t=115014808400007&r=1&w=2
V3 http://marc.theaimsgroup.com/?l=linux-kernel&m=115024767022346&w=2
V4 http://marc.theaimsgroup.com/?l=linux-kernel&m=115047968808926&w=2

Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# 6ab3d562 30-Jun-2006 Jörn Engel <joern@wohnheim.fh-wedel.de>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>


# e041c683 27-Mar-2006 Alan Stern <stern@rowland.harvard.edu>

[PATCH] Notifier chain update: API changes

The kernel's implementation of notifier chains is unsafe. There is no
protection against entries being added to or removed from a chain while the
chain is in use. The issues were discussed in this thread:

http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2

We noticed that notifier chains in the kernel fall into two basic usage
classes:

"Blocking" chains are always called from a process context
and the callout routines are allowed to sleep;

"Atomic" chains can be called from an atomic context and
the callout routines are not allowed to sleep.

We decided to codify this distinction and make it part of the API. Therefore
this set of patches introduces three new, parallel APIs: one for blocking
notifiers, one for atomic notifiers, and one for "raw" notifiers (which is
really just the old API under a new name). New kinds of data structures are
used for the heads of the chains, and new routines are defined for
registration, unregistration, and calling a chain. The three APIs are
explained in include/linux/notifier.h and their implementation is in
kernel/sys.c.

With atomic and blocking chains, the implementation guarantees that the chain
links will not be corrupted and that chain callers will not get messed up by
entries being added or removed. For raw chains the implementation provides no
guarantees at all; users of this API must provide their own protections. (The
idea was that situations may come up where the assumptions of the atomic and
blocking APIs are not appropriate, so it should be possible for users to
handle these things in their own way.)

There are some limitations, which should not be too hard to live with. For
atomic/blocking chains, registration and unregistration must always be done in
a process context since the chain is protected by a mutex/rwsem. Also, a
callout routine for a non-raw chain must not try to register or unregister
entries on its own chain. (This did happen in a couple of places and the code
had to be changed to avoid it.)

Since atomic chains may be called from within an NMI handler, they cannot use
spinlocks for synchronization. Instead we use RCU. The overhead falls almost
entirely in the unregister routine, which is okay since unregistration is much
less frequent that calling a chain.

Here is the list of chains that we adjusted and their classifications. None
of them use the raw API, so for the moment it is only a placeholder.

ATOMIC CHAINS
-------------
arch/i386/kernel/traps.c: i386die_chain
arch/ia64/kernel/traps.c: ia64die_chain
arch/powerpc/kernel/traps.c: powerpc_die_chain
arch/sparc64/kernel/traps.c: sparc64die_chain
arch/x86_64/kernel/traps.c: die_chain
drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list
kernel/panic.c: panic_notifier_list
kernel/profile.c: task_free_notifier
net/bluetooth/hci_core.c: hci_notifier
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain
net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain
net/ipv6/addrconf.c: inet6addr_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_chain
net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain
net/netlink/af_netlink.c: netlink_chain

BLOCKING CHAINS
---------------
arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain
arch/s390/kernel/process.c: idle_chain
arch/x86_64/kernel/process.c idle_notifier
drivers/base/memory.c: memory_chain
drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list
drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list
drivers/macintosh/adb.c: adb_client_list
drivers/macintosh/via-pmu.c sleep_notifier_list
drivers/macintosh/via-pmu68k.c sleep_notifier_list
drivers/macintosh/windfarm_core.c wf_client_list
drivers/usb/core/notify.c usb_notifier_list
drivers/video/fbmem.c fb_notifier_list
kernel/cpu.c cpu_chain
kernel/module.c module_notify_list
kernel/profile.c munmap_notifier
kernel/profile.c task_exit_notifier
kernel/sys.c reboot_notifier_list
net/core/dev.c netdev_chain
net/decnet/dn_dev.c: dnaddr_chain
net/ipv4/devinet.c: inetaddr_chain

It's possible that some of these classifications are wrong. If they are,
please let us know or submit a patch to fix them. Note that any chain that
gets called very frequently should be atomic, because the rwsem read-locking
used for blocking chains is very likely to incur cache misses on SMP systems.
(However, if the chain's callout routines may sleep then the chain cannot be
atomic.)

The patch set was written by Alan Stern and Chandra Seetharaman, incorporating
material written by Keith Owens and suggestions from Paul McKenney and Andrew
Morton.

[jes@sgi.com: restructure the notifier chain initialization macros]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# c59ede7b 11-Jan-2006 Randy Dunlap <rdunlap@infradead.org>

[PATCH] move capable() to capability.h

- Move capable() from sched.h to capability.h;

- Use <linux/capability.h> where capable() is used
(in include/, block/, ipc/, kernel/, a few drivers/,
mm/, security/, & sound/;
many more drivers/ to go)

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>


# 8039de10 10-Jan-2006 Helge Deller <deller@parisc-linux.org>

[PARISC] Add __read_mostly section for parisc

Flag a whole bunch of things as __read_mostly on parisc. Also flag a few
branches as unlikely() and cleanup a bit of code.

Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>


# 93b1fae4 09-Jan-2006 Adrian Bunk <bunk@stusta.de>

spelling: s/trough/through/

Additionally, one comment was reformulated by Joe Perches <joe@perches.com>.

Signed-off-by: Adrian Bunk <bunk@stusta.de>


# 34994952 21-Oct-2005 Grant Grundler <grundler@parisc-linux.org>

[PARISC] Use work queue in LED/LCD driver instead of tasklet.

2.6.12-rc1-pa6 use work queue in LED/LCD driver instead of tasklet.

Main advantage is it allows use of msleep() in the led_LCD_driver to
"atomically" perform two MMIO writes (CMD, then DATA).
Lead to nice cleanup of the main led_work_func() and led_LCD_driver().
Kudos to David for being persistent.

From: David Pye <dmp@davidmpye.dyndns.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>


# e5ed6399 03-Oct-2005 Herbert Xu <herbert@gondor.apana.org.au>

[IPV4]: Replace __in_dev_get with __in_dev_get_rcu/rtnl

The following patch renames __in_dev_get() to __in_dev_get_rtnl() and
introduces __in_dev_get_rcu() to cover the second case.

1) RCU with refcnt should use in_dev_get().
2) RCU without refcnt should use __in_dev_get_rcu().
3) All others must hold RTNL and use __in_dev_get_rtnl().

There is one exception in net/ipv4/route.c which is in fact a pre-existing
race condition. I've marked it as such so that we remember to fix it.

This patch is based on suggestions and prior work by Suzanne Wood and
Paul McKenney.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>


# 1da177e4 16-Apr-2005 Linus Torvalds <torvalds@ppc970.osdl.org>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!