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		ac331d158e
		
	
	
	
	
		
			
			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 <kosaki.motohiro@jp.fujitsu.com> Cc: "Paul Menage" <menage@google.com> Reviewed-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			103 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			103 lines
		
	
	
		
			3.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __LINUX_KMOD_H__
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| #define __LINUX_KMOD_H__
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| 
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| /*
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|  *	include/linux/kmod.h
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|  *
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|  *      This program is free software; you can redistribute it and/or modify
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|  *      it under the terms of the GNU General Public License as published by
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|  *      the Free Software Foundation; either version 2 of the License, or
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|  *      (at your option) any later version.
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|  *
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|  *      This program is distributed in the hope that it will be useful,
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|  *      but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  *      GNU General Public License for more details.
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|  *
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|  *      You should have received a copy of the GNU General Public License
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|  *      along with this program; if not, write to the Free Software
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|  *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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|  */
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| 
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| #include <linux/gfp.h>
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| #include <linux/stddef.h>
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| #include <linux/errno.h>
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| #include <linux/compiler.h>
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| 
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| #define KMOD_PATH_LEN 256
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| 
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| #ifdef CONFIG_MODULES
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| /* modprobe exit status on success, -ve on error.  Return value
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|  * usually useless though. */
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| extern int request_module(const char * name, ...) __attribute__ ((format (printf, 1, 2)));
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| #define try_then_request_module(x, mod...) ((x) ?: (request_module(mod), (x)))
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| #else
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| static inline int request_module(const char * name, ...) { return -ENOSYS; }
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| #define try_then_request_module(x, mod...) (x)
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| #endif
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| 
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| 
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| struct key;
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| struct file;
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| struct subprocess_info;
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| 
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| /* Allocate a subprocess_info structure */
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| struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,
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| 						  char **envp, gfp_t gfp_mask);
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| 
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| /* Set various pieces of state into the subprocess_info structure */
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| void call_usermodehelper_setkeys(struct subprocess_info *info,
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| 				 struct key *session_keyring);
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| int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info,
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| 				  struct file **filp);
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| void call_usermodehelper_setcleanup(struct subprocess_info *info,
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| 				    void (*cleanup)(char **argv, char **envp));
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| 
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| enum umh_wait {
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| 	UMH_NO_WAIT = -1,	/* don't wait at all */
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| 	UMH_WAIT_EXEC = 0,	/* wait for the exec, but not the process */
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| 	UMH_WAIT_PROC = 1,	/* wait for the process to complete */
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| };
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| 
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| /* Actually execute the sub-process */
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| int call_usermodehelper_exec(struct subprocess_info *info, enum umh_wait wait);
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| 
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| /* Free the subprocess_info. This is only needed if you're not going
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|    to call call_usermodehelper_exec */
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| void call_usermodehelper_freeinfo(struct subprocess_info *info);
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| 
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| static inline int
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| call_usermodehelper(char *path, char **argv, char **envp, enum umh_wait wait)
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| {
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| 	struct subprocess_info *info;
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| 	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
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| 
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| 	info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
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| 	if (info == NULL)
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| 		return -ENOMEM;
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| 	return call_usermodehelper_exec(info, wait);
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| }
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| 
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| static inline int
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| call_usermodehelper_keys(char *path, char **argv, char **envp,
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| 			 struct key *session_keyring, enum umh_wait wait)
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| {
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| 	struct subprocess_info *info;
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| 	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
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| 
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| 	info = call_usermodehelper_setup(path, argv, envp, gfp_mask);
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| 	if (info == NULL)
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| 		return -ENOMEM;
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| 
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| 	call_usermodehelper_setkeys(info, session_keyring);
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| 	return call_usermodehelper_exec(info, wait);
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| }
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| 
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| extern void usermodehelper_init(void);
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| 
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| struct file;
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| extern int call_usermodehelper_pipe(char *path, char *argv[], char *envp[],
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| 				    struct file **filp);
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| 
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| #endif /* __LINUX_KMOD_H__ */
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