android_kernel_xiaomi_sm8350/include/linux/kmod.h
Rafael J. Wysocki 1bfcf1304e pm: rework disabling of user mode helpers during suspend/hibernation
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 <rjw@sisk.pl>
Cc: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 11:21:29 -07:00

106 lines
3.4 KiB
C

#ifndef __LINUX_KMOD_H__
#define __LINUX_KMOD_H__
/*
* include/linux/kmod.h
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/gfp.h>
#include <linux/stddef.h>
#include <linux/errno.h>
#include <linux/compiler.h>
#define KMOD_PATH_LEN 256
#ifdef CONFIG_MODULES
/* modprobe exit status on success, -ve on error. Return value
* usually useless though. */
extern int request_module(const char * name, ...) __attribute__ ((format (printf, 1, 2)));
#define try_then_request_module(x, mod...) ((x) ?: (request_module(mod), (x)))
#else
static inline int request_module(const char * name, ...) { return -ENOSYS; }
#define try_then_request_module(x, mod...) (x)
#endif
struct key;
struct file;
struct subprocess_info;
/* Allocate a subprocess_info structure */
struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
char **envp, gfp_t gfp_mask);
/* Set various pieces of state into the subprocess_info structure */
void call_usermodehelper_setkeys(struct subprocess_info *info,
struct key *session_keyring);
int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
struct file **filp);
void call_usermodehelper_setcleanup(struct subprocess_info *info,
void (*cleanup)(char **argv, char **envp));
enum umh_wait {
UMH_NO_WAIT = -1, /* don't wait at all */
UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */
UMH_WAIT_PROC = 1, /* wait for the process to complete */
};
/* Actually execute the sub-process */
int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
/* Free the subprocess_info. This is only needed if you're not going
to call call_usermodehelper_exec */
void call_usermodehelper_freeinfo(struct subprocess_info *info);
static inline int
call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
{
struct subprocess_info *info;
gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
if (info == NULL)
return -ENOMEM;
return call_usermodehelper_exec(info, wait);
}
static inline int
call_usermodehelper_keys(char *path, char **argv, char **envp,
struct key *session_keyring, enum umh_wait wait)
{
struct subprocess_info *info;
gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
if (info == NULL)
return -ENOMEM;
call_usermodehelper_setkeys(info, session_keyring);
return call_usermodehelper_exec(info, wait);
}
extern void usermodehelper_init(void);
struct file;
extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[],
struct file **filp);
extern int usermodehelper_disable(void);
extern void usermodehelper_enable(void);
#endif /* __LINUX_KMOD_H__ */