linux-toradex.git/include/linux/moduleparam.h, branch Colibri_T30_LinuxImageV2.1Beta2_20140206

module: reorder kparam_array to remove alignment padding on 64 bit builds

2011-05-19T07:25:25+00:00

Reorder structure kparam_array to remove 8 bytes of alignment padding on
64 bit builds, dropping its size from 40 to 32 bytes.

Also update the macro module_param_array_named to initialise the
structure using its member names to allow it to be changed without
touching all its call sites.

'git grep' finds module_param_array in 1037 places so this patch will
save a small amount of data space across many modules.

Signed-off-by: Richard Kennedy 
Signed-off-by: Rusty Russell

param: add null statement to compiled-in module params

2011-01-24T04:02:52+00:00

Add an unused struct declaration statement requiring a
terminating semicolon to the compile-in case to provoke an
error if __MODULE_INFO() is used without the terminating
semicolon. Previously MODULE_ALIAS("foo") (no semicolon)
compiled fine if MODULE was not selected.

Cc: Dan Carpenter 
Signed-off-by: Linus Walleij 
Signed-off-by: Rusty Russell

modules: no need to align .modinfo strings

2010-10-26T23:52:13+00:00

gcc aligns strings as a performance consideration for those cases where
strings are being used a lot.

Their use is not performance critical, and hence it seems better to save
some space.

Signed-off-by: Jan Beulich 
Acked-by: Rusty Russell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

param: don't deref arg in __same_type() checks

2010-08-11T13:34:41+00:00

gcc allows this when arg is a function, but sparse complains:

drivers/char/ipmi/ipmi_watchdog.c:303:1: error: cannot dereference this type
drivers/char/ipmi/ipmi_watchdog.c:307:1: error: cannot dereference this type
drivers/char/ipmi/ipmi_watchdog.c:311:1: error: cannot dereference this type

Reported-by: Randy Dunlap 
Tested-by: Randy Dunlap 
Signed-off-by: Rusty Russell

param: add kerneldoc to moduleparam.h

2010-08-11T13:34:21+00:00

Also reorders the macros with the most common ones at the top.

Signed-off-by: Rusty Russell 
Reviewed-by: Takashi Iwai 
Tested-by: Phil Carmody

param: locking for kernel parameters

2010-08-11T13:34:20+00:00

There may be cases (most obviously, sysfs-writable charp parameters) where
a module needs to prevent sysfs access to parameters.

Rather than express this in terms of a big lock, the functions are
expressed in terms of what they protect against.  This is clearer, esp.
if the implementation changes to a module-level or even param-level lock.

Signed-off-by: Rusty Russell 
Reviewed-by: Takashi Iwai 
Tested-by: Phil Carmody

param: make param sections const.

2010-08-11T13:34:19+00:00

Since this section can be read-only (they're in .rodata), they should
always have been const.  Minor flow-through various functions.

Signed-off-by: Rusty Russell 
Tested-by: Phil Carmody

param: add a free hook to kernel_param_ops.

2010-08-11T13:34:18+00:00

This allows us to generalize the KPARAM_KMALLOCED flag, by calling a function
on every parameter when a module is unloaded.

Signed-off-by: Rusty Russell 
Reviewed-by: Takashi Iwai 
Tested-by: Phil Carmody

param: use ops in struct kernel_param, rather than get and set fns directly

2010-08-11T13:34:13+00:00

This is more kernel-ish, saves some space, and also allows us to
expand the ops without breaking all the callers who are happy for the
new members to be NULL.

The few places which defined their own param types are changed to the
new scheme (more which crept in recently fixed in following patches).

Since we're touching them anyway, we change get() and set() to take a
const struct kernel_param (which they really are).  This causes some
harmless warnings until we fix them (in following patches).

To reduce churn, module_param_call creates the ops struct so the callers
don't have to change (and casts the functions to reduce warnings).
The modern version which takes an ops struct is called module_param_cb.

Signed-off-by: Rusty Russell 
Reviewed-by: Takashi Iwai 
Tested-by: Phil Carmody 
Cc: "David S. Miller" 
Cc: Ville Syrjala 
Cc: Dmitry Torokhov 
Cc: Alessandro Rubini 
Cc: Michal Januszewski 
Cc: Trond Myklebust 
Cc: "J. Bruce Fields" 
Cc: Neil Brown 
Cc: linux-kernel@vger.kernel.org
Cc: linux-input@vger.kernel.org
Cc: linux-fbdev-devel@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: netdev@vger.kernel.org

param: fix lots of bugs with writing charp params from sysfs, by leaking mem.

2009-10-28T22:26:17+00:00

e180a6b7759a "param: fix charp parameters set via sysfs" fixed the case
where charp parameters written via sysfs were freed, leaving drivers
accessing random memory.

Unfortunately, storing a flag in the kparam struct was a bad idea: it's
rodata so setting it causes an oops on some archs.  But that's not all:

1) module_param_array() on charp doesn't work reliably, since we use an
   uninitialized temporary struct kernel_param.
2) there's a fundamental race if a module uses this parameter and then
   it's changed: they will still access the old, freed, memory.

The simplest fix (ie. for 2.6.32) is to never free the memory.  This
prevents all these problems, at cost of a memory leak.  In practice, there
are only 18 places where a charp is writable via sysfs, and all are
root-only writable.

Reported-by: Takashi Iwai 
Cc: Sitsofe Wheeler 
Cc: Frederic Weisbecker 
Cc: Christof Schmitt 
Signed-off-by: Rusty Russell 
Cc: stable@kernel.org