LXR linux/include/linux/kmod.h

   1#ifndef __LINUX_KMOD_H__
   2#define __LINUX_KMOD_H__
   3
   4/*
   5 *      include/linux/kmod.h
   6 *
   7 *      This program is free software; you can redistribute it and/or modify
   8 *      it under the terms of the GNU General Public License as published by
   9 *      the Free Software Foundation; either version 2 of the License, or
  10 *      (at your option) any later version.
  11 *
  12 *      This program is distributed in the hope that it will be useful,
  13 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *      GNU General Public License for more details.
  16 *
  17 *      You should have received a copy of the GNU General Public License
  18 *      along with this program; if not, write to the Free Software
  19 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22#include <linux/gfp.h>
  23#include <linux/stddef.h>
  24#include <linux/errno.h>
  25#include <linux/compiler.h>
  26
  27#define KMOD_PATH_LEN 256
  28
  29#ifdef CONFIG_MODULES
  30/* modprobe exit status on success, -ve on error.  Return value
  31 * usually useless though. */
  32extern int __request_module(bool wait, const char *name, ...) \
  33        __attribute__((format(printf, 2, 3)));
  34#define request_module(mod...) __request_module(true, mod)
  35#define request_module_nowait(mod...) __request_module(false, mod)
  36#define try_then_request_module(x, mod...) \
  37        ((x) ?: (__request_module(true, mod), (x)))
  38#else
  39static inline int request_module(const char *name, ...) { return -ENOSYS; }
  40static inline int request_module_nowait(const char *name, ...) { return -ENOSYS; }
  41#define try_then_request_module(x, mod...) (x)
  42#endif
  43
  44
  45struct key;
  46struct file;
  47struct subprocess_info;
  48
  49/* Allocate a subprocess_info structure */
  50struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
  51                                                  char **envp, gfp_t gfp_mask);
  52
  53/* Set various pieces of state into the subprocess_info structure */
  54void call_usermodehelper_setkeys(struct subprocess_info *info,
  55                                 struct key *session_keyring);
  56int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
  57                                  struct file **filp);
  58void call_usermodehelper_setcleanup(struct subprocess_info *info,
  59                                    void (*cleanup)(char **argv, char **envp));
  60
  61enum umh_wait {
  62        UMH_NO_WAIT = -1,       /* don't wait at all */
  63        UMH_WAIT_EXEC = 0,      /* wait for the exec, but not the process */
  64        UMH_WAIT_PROC = 1,      /* wait for the process to complete */
  65};
  66
  67/* Actually execute the sub-process */
  68int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
  69
  70/* Free the subprocess_info. This is only needed if you're not going
  71   to call call_usermodehelper_exec */
  72void call_usermodehelper_freeinfo(struct subprocess_info *info);
  73
  74static inline int
  75call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
  76{
  77        struct subprocess_info *info;
  78        gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
  79
  80        info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
  81        if (info == NULL)
  82                return -ENOMEM;
  83        return call_usermodehelper_exec(info, wait);
  84}
  85
  86static inline int
  87call_usermodehelper_keys(char *path, char **argv, char **envp,
  88                         struct key *session_keyring, enum umh_wait wait)
  89{
  90        struct subprocess_info *info;
  91        gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
  92
  93        info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
  94        if (info == NULL)
  95                return -ENOMEM;
  96
  97        call_usermodehelper_setkeys(info, session_keyring);
  98        return call_usermodehelper_exec(info, wait);
  99}
 100
 101extern void usermodehelper_init(void);
 102
 103struct file;
 104extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[],
 105                                    struct file **filp);
 106
 107extern int usermodehelper_disable(void);
 108extern void usermodehelper_enable(void);
 109
 110#endif /* __LINUX_KMOD_H__ */
 111