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(const char * name, ...) __attribute__ ((format (printf, 1, 2)));
  33#define try_then_request_module(x, mod...) ((x) ?: (request_module(mod), (x)))
  34#else
  35static inline int request_module(const char * name, ...) { return -ENOSYS; }
  36#define try_then_request_module(x, mod...) (x)
  37#endif
  38
  39
  40struct key;
  41struct file;
  42struct subprocess_info;
  43
  44/* Allocate a subprocess_info structure */
  45struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
  46                                                  char **envp, gfp_t gfp_mask);
  47
  48/* Set various pieces of state into the subprocess_info structure */
  49void call_usermodehelper_setkeys(struct subprocess_info *info,
  50                                 struct key *session_keyring);
  51int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
  52                                  struct file **filp);
  53void call_usermodehelper_setcleanup(struct subprocess_info *info,
  54                                    void (*cleanup)(char **argv, char **envp));
  55
  56enum umh_wait {
  57        UMH_NO_WAIT = -1,       /* don't wait at all */
  58        UMH_WAIT_EXEC = 0,      /* wait for the exec, but not the process */
  59        UMH_WAIT_PROC = 1,      /* wait for the process to complete */
  60};
  61
  62/* Actually execute the sub-process */
  63int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
  64
  65/* Free the subprocess_info. This is only needed if you're not going
  66   to call call_usermodehelper_exec */
  67void call_usermodehelper_freeinfo(struct subprocess_info *info);
  68
  69static inline int
  70call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
  71{
  72        struct subprocess_info *info;
  73        gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
  74
  75        info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
  76        if (info == NULL)
  77                return -ENOMEM;
  78        return call_usermodehelper_exec(info, wait);
  79}
  80
  81static inline int
  82call_usermodehelper_keys(char *path, char **argv, char **envp,
  83                         struct key *session_keyring, enum umh_wait wait)
  84{
  85        struct subprocess_info *info;
  86        gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
  87
  88        info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
  89        if (info == NULL)
  90                return -ENOMEM;
  91
  92        call_usermodehelper_setkeys(info, session_keyring);
  93        return call_usermodehelper_exec(info, wait);
  94}
  95
  96extern void usermodehelper_init(void);
  97
  98struct file;
  99extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[],
 100                                    struct file **filp);
 101
 102#endif /* __LINUX_KMOD_H__ */
 103