Commit f44f7f96a2 ("RTC: Initialize kernel state from RTC") uncovered
an issue in a number of RTC drivers, where the drivers call
rtc_device_register before initializing the clientdata.
This frequently results in null pointer dereferences when the
rtc_device_register immediately makes use of the rtc device, calling
rtc_read_alarm.
The solution is to ensure the clientdata is initialized prior to registering
the rtc device.
CC: Wolfram Sang <w.sang@pengutronix.de>
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: rtc-linux@googlegroups.com
Signed-off-by: John Stultz <john.stultz@linaro.org>
Some rtc drivers use the ioctl method instead of the alarm_irq_enable
method for enabling alarm interupts. With the new virtualized RTC
rework, its important for drivers to use the alarm_irq_enable instead.
This patch converts the drivers that use the AIE ioctl method to
use the alarm_irq_enable method. Other ioctl cmds are left untouched.
I have not been able to test or even compile most of these drivers.
Any help to make sure this change is correct would be appreciated!
CC: Alessandro Zummo <a.zummo@towertech.it>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Reported-by: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Tested-by: Marcelo Roberto Jimenez <mroberto@cpti.cetuc.puc-rio.br>
Signed-off-by: John Stultz <john.stultz@linaro.org>
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.
The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.
New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.
The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.
Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.
Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.
===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}
@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}
@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};
@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};
@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};
@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};
@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};
// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};
@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};
// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};
// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};
// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};
@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};
// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////
@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};
@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};
@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};
@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>
All these files use the big kernel lock in a trivial
way to serialize their private file operations,
typically resulting from an earlier semi-automatic
pushdown from VFS.
None of these drivers appears to want to lock against
other code, and they all use the BKL as the top-level
lock in their file operations, meaning that there
is no lock-order inversion problem.
Consequently, we can remove the BKL completely,
replacing it with a per-file mutex in every case.
Using a scripted approach means we can avoid
typos.
These drivers do not seem to be under active
maintainance from my brief investigation. Apologies
to those maintainers that I have missed.
file=$1
name=$2
if grep -q lock_kernel ${file} ; then
if grep -q 'include.*linux.mutex.h' ${file} ; then
sed -i '/include.*<linux\/smp_lock.h>/d' ${file}
else
sed -i 's/include.*<linux\/smp_lock.h>.*$/include <linux\/mutex.h>/g' ${file}
fi
sed -i ${file} \
-e "/^#include.*linux.mutex.h/,$ {
1,/^\(static\|int\|long\)/ {
/^\(static\|int\|long\)/istatic DEFINE_MUTEX(${name}_mutex);
} }" \
-e "s/\(un\)*lock_kernel\>[ ]*()/mutex_\1lock(\&${name}_mutex)/g" \
-e '/[ ]*cycle_kernel_lock();/d'
else
sed -i -e '/include.*\<smp_lock.h\>/d' ${file} \
-e '/cycle_kernel_lock()/d'
fi
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Commit b485fe5ea ("rtc/m41t80: use rtc_valid_tm() to check returned tm")
added rtc_valid_tm to m41t80_rtc_read_alarm() but it was wrong while the
t->time does not contain complete date/time.
This patch also fixes a warning:
warning: passing argument 1 of 'rtc_valid_tm' from incompatible pointer type
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use rtc_valid_tm() to check returned struct rtc_time *tm - it can avoid
returning wrong tm value.
Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use nonseekable_open() for this since seeking is not supported anyway.
Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Gortmaker <p_gortmaker@yahoo.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These are the last remaining device drivers using
the ->ioctl file operation in the drivers directory
(except from v4l drivers).
[fweisbec: drop i8k pushdown as it has been done from
procfs pushdown branch already]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Compared to the other supported chips, the m41t62 uses a different
register to set the square wave frequency.
Signed-off-by: Daniel Glockner <dg@emlix.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Brownell <david-b@pacbell.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change drivers/rtc/ to use the new bcd2bin/bin2bcd functions instead of
the obsolete BCD_TO_BIN/BIN_TO_BCD/BCD2BIN/BIN2BCD macros.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for M41T65 Real Time Clock chip.
The main differences I see between the M41T65 and M41T80 are that:
1) The M41T65 watchdog timer has three bits controlling resolution
(versus two for the M41T80).
2) There is no register 0x13 for controlling square-wave output.
Signed-off-by: Steven A. Falco <sfalco@harris.com>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: "Maciej W. Rozycki" <macro@linux-mips.org>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sort the header inclusions for readability. No functional changes.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexander Bigga <ab@mycable.de>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The driver uses printk(), but does not include <linux/kernel.h> -- add it.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexander Bigga <ab@mycable.de>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Watchdog handlers within the driver make use of "save_client" -- make sure it
has been initalized before the handlers are registered.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexander Bigga <ab@mycable.de>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Based on earlier work by Jon Smirl and Jochen Friedrich.
Update most new-style i2c drivers to use standard module aliasing
instead of the old driver_name/type driver matching scheme. I've
left the video drivers apart (except for SoC camera drivers) as
they're a bit more diffcult to deal with, they'll have their own
patch later.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Jochen Friedrich <jochen@scram.de>
Based on earlier work by Jon Smirl and Jochen Friedrich.
This patch allows new-style i2c chip drivers to have alias names using
the official kernel aliasing system and MODULE_DEVICE_TABLE(). At this
point, the old i2c driver binding scheme (driver_name/type) is still
supported.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Jochen Friedrich <jochen@scram.de>
Cc: Jon Smirl <jonsmirl@gmail.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
The new rtc-m41t80 driver name doesn't match its module name, which
prevents it from properly hotplugging. Since it's new, no platforms yet
depend on that name ... so this patch fixes the driver name to match its
module name, rather than going the other way around with a MODULE_ALIAS().
NOTE: This sort of bug is a new thing to watch out for with new-style I2C
drivers; previously I2C couldn't hotplug.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a watchdog driver interface to rtc-m41t80 driver. This is derived from
works by Alexander Bigga <ab@mycable.de>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Alexander Bigga <ab@mycable.de>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a new-style i2c driver for ST M41T80 series RTC chip, derived from
works by Alexander Bigga <ab@mycable.de> who wrote the original
rtc-m41txx.c based on drivers/i2c/chips/m41t00.c driver.
This driver supports M41T8[0-4] and M41ST8[457]. The old m41t00 driver
supports M41T00, M41T81 and M41T85(M41ST85). While the M41T00 chip is now
supported by rtc-ds1307 driver, this driver does not include support for
the chip.
[akpm@linux-foundation.org: remove bogus `static']
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Alexander Bigga <ab@mycable.de>
Acked-by: Mark A. Greer <mgreer@mvista.com>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
