linux-toradex.git/include/linux/kmod.h, branch tegra-10.7.1

module: try_then_request_module must wait

2009-04-09T14:49:44+00:00

Since the whole point of try_then_request_module is to retry
the operation after a module has been loaded, we must wait for
the module to fully load.

Otherwise all sort of things start breaking, e.g., you won't
be able to read your encrypted disks on the first attempt.

Signed-off-by: Herbert Xu 
Tested-by: Maciej Rutecki 
Tested-by: Patrick McHardy 
Signed-off-by: Linus Torvalds

module: create a request_module_nowait()

2009-03-31T02:35:35+00:00

There seems to be a common pattern in the kernel where drivers want to
call request_module() from inside a module_init() function. Currently
this would deadlock.

As a result, several drivers go through hoops like scheduling things via
kevent, or creating custom work queues (because kevent can deadlock on them).

This patch changes this to use a request_module_nowait() function macro instead,
which just fires the modprobe off but doesn't wait for it, and thus avoids the
original deadlock entirely.

On my laptop this already results in one less kernel thread running..

(Includes Jiri's patch to use enum umh_wait)

Signed-off-by: Arjan van de Ven 
Signed-off-by: Rusty Russell  (bool-ified)
Cc: Jiri Slaby

pm: rework disabling of user mode helpers during suspend/hibernation

2008-10-16T18:21:29+00:00

We currently use a PM notifier to disable user mode helpers before suspend
and hibernation and to re-enable them during resume.  However, this is not
an ideal solution, because if any drivers want to upload firmware into
memory before suspend, they have to use a PM notifier for this purpose and
there is no guarantee that the ordering of PM notifiers will be as
expected (ie.  the notifier that disables user mode helpers has to be run
after the driver's notifier used for uploading the firmware).

For this reason, it seems better to move the disabling and enabling of
user mode helpers to separate functions that will be called by the PM core
as necessary.

[akpm@linux-foundation.org: remove unneeded ifdefs]
Signed-off-by: Rafael J. Wysocki 
Cc: Alan Stern 
Acked-by: Pavel Machek 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

call_usermodehelper(): increase reliability

2008-07-25T17:53:28+00:00

Presently call_usermodehelper_setup() uses GFP_ATOMIC.  but it can return
NULL _very_ easily.

GFP_ATOMIC is needed only when we can't sleep.  and, GFP_KERNEL is robust
and better.

thus, I add gfp_mask argument to call_usermodehelper_setup().

So, its callers pass the gfp_t as below:

call_usermodehelper() and call_usermodehelper_keys():
	depend on 'wait' argument.
call_usermodehelper_pipe():
	always GFP_KERNEL because always run under process context.
orderly_poweroff():
	pass to GFP_ATOMIC because may run under interrupt context.

Signed-off-by: KOSAKI Motohiro 
Cc: "Paul Menage" 
Reviewed-by: Li Zefan 
Acked-by: Jeremy Fitzhardinge 
Cc: Rusty Russell 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

remove CONFIG_KMOD from core kernel code

2008-07-22T09:24:31+00:00

Always compile request_module when the kernel allows modules.

Signed-off-by: Johannes Berg 
Signed-off-by: Rusty Russell

rework try_then_request_module to do less in non-modular kernels

2008-07-22T09:24:29+00:00

This reworks try_then_request_module to only invoke the "lookup"
function "x" once when the kernel is not modular.

Signed-off-by: Johannes Berg 
Signed-off-by: Rusty Russell

usermodehelper: Tidy up waiting

2007-07-18T15:47:40+00:00

Rather than using a tri-state integer for the wait flag in
call_usermodehelper_exec, define a proper enum, and use that.  I've
preserved the integer values so that any callers I've missed should
still work OK.

Signed-off-by: Jeremy Fitzhardinge 
Cc: James Bottomley 
Cc: Randy Dunlap 
Cc: Christoph Hellwig 
Cc: Andi Kleen 
Cc: Paul Mackerras 
Cc: Johannes Berg 
Cc: Ralf Baechle 
Cc: Bjorn Helgaas 
Cc: Joel Becker 
Cc: Tony Luck 
Cc: Kay Sievers 
Cc: Srivatsa Vaddagiri 
Cc: Oleg Nesterov 
Cc: David Howells

usermodehelper: split setup from execution

2007-07-18T15:47:40+00:00

Rather than having hundreds of variations of call_usermodehelper for
various pieces of usermode state which could be set up, split the
info allocation and initialization from the actual process execution.

This means the general pattern becomes:
 info = call_usermodehelper_setup(path, argv, envp); /* basic state */
 call_usermodehelper_(info, stuff...);	/* extra state */
 call_usermodehelper_exec(info, wait);	/* run process and free info */

This patch introduces wrappers for all the existing calling styles for
call_usermodehelper_*, but folds their implementations into one.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Andi Kleen 
Cc: Rusty Russell 
Cc: David Howells 
Cc: Bj?rn Steinbrink 
Cc: Randy Dunlap

Revert "Driver core: let request_module() send a /sys/modules/kmod/-uevent"

2007-02-23T22:54:57+00:00

This reverts commit c353c3fb0700a3c17ea2b0237710a184232ccd7f.

It turns out that we end up with a loop trying to load the unix
module and calling netfilter to do that.  Will redo the patch
later to not have this loop.

Acked-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman

Driver core: let request_module() send a /sys/modules/kmod/-uevent

2007-02-16T23:19:15+00:00

On recent systems, calls to /sbin/modprobe are handled by udev depending
on the kind of device the kernel has discovered. This patch creates an
uevent for the kernels internal request_module(), to let udev take control
over the request, instead of forking the binary directly by the kernel.
The direct execution of /sbin/modprobe can be disabled by setting:
  /sys/module/kmod/mod_request_helper (/proc/sys/kernel/modprobe)
to an empty string, the same way /proc/sys/kernel/hotplug is disabled on an
udev system.

Signed-off-by: Kay Sievers 
Signed-off-by: Greg Kroah-Hartman