Commit 785042f2 authored by Boaz Harrosh's avatar Boaz Harrosh Committed by Linus Torvalds
Browse files

kmod: move call_usermodehelper_fns() to .c file and unexport all it's helpers 



If we move call_usermodehelper_fns() to kmod.c file and EXPORT_SYMBOL it
we can avoid exporting all it's helper functions:
	call_usermodehelper_setup
	call_usermodehelper_setfns
	call_usermodehelper_exec
And make all of them static to kmod.c

Since the optimizer will see all these as a single call site it will
inline them inside call_usermodehelper_fns().  So we loose the call to
_fns but gain 3 calls to the helpers.  (Not that it matters)

Signed-off-by: default avatarBoaz Harrosh <bharrosh@panasas.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 81ab6e7b

include/linux/kmod.h

+2 −28
Original line number Diff line number Diff line
@@ -66,36 +66,10 @@ struct subprocess_info { 
	void *data;

};



/* 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_setfns(struct subprocess_info *info,

		    int (*init)(struct subprocess_info *info, struct cred *new),

		    void (*cleanup)(struct subprocess_info *info),

		    void *data);



/* Actually execute the sub-process */

int call_usermodehelper_exec(struct subprocess_info *info, int wait);



static inline int

extern int

call_usermodehelper_fns(char *path, char **argv, char **envp, int wait,

			int (*init)(struct subprocess_info *info, struct cred *new),

			void (*cleanup)(struct subprocess_info *), void *data)

{

	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_setfns(info, init, cleanup, data);



	return call_usermodehelper_exec(info, wait);

}

			void (*cleanup)(struct subprocess_info *), void *data);



static inline int

call_usermodehelper(char *path, char **argv, char **envp, int wait)

kernel/kmod.c

+22 −3
Original line number Diff line number Diff line
@@ -478,6 +478,7 @@ static void helper_unlock(void) 
 * structure.  This should be passed to call_usermodehelper_exec to

 * exec the process and free the structure.

 */

static

struct subprocess_info *call_usermodehelper_setup(char *path, char **argv,

						  char **envp, gfp_t gfp_mask)

{
@@ -493,7 +494,6 @@ struct subprocess_info *call_usermodehelper_setup(char *path, char **argv, 
  out:

	return sub_info;

}

EXPORT_SYMBOL(call_usermodehelper_setup);



/**

 * call_usermodehelper_setfns - set a cleanup/init function
@@ -511,6 +511,7 @@ EXPORT_SYMBOL(call_usermodehelper_setup); 
 * Function must be runnable in either a process context or the

 * context in which call_usermodehelper_exec is called.

 */

static

void call_usermodehelper_setfns(struct subprocess_info *info,

		    int (*init)(struct subprocess_info *info, struct cred *new),

		    void (*cleanup)(struct subprocess_info *info),
@@ -520,7 +521,6 @@ void call_usermodehelper_setfns(struct subprocess_info *info, 
	info->init = init;

	info->data = data;

}

EXPORT_SYMBOL(call_usermodehelper_setfns);



/**

 * call_usermodehelper_exec - start a usermode application
@@ -534,6 +534,7 @@ EXPORT_SYMBOL(call_usermodehelper_setfns); 
 * asynchronously if wait is not set, and runs as a child of keventd.

 * (ie. it runs with full root capabilities).

 */

static

int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)

{

	DECLARE_COMPLETION_ONSTACK(done);
@@ -575,7 +576,25 @@ unlock: 
	helper_unlock();

	return retval;

}

EXPORT_SYMBOL(call_usermodehelper_exec);



int call_usermodehelper_fns(

	char *path, char **argv, char **envp, int wait,

	int (*init)(struct subprocess_info *info, struct cred *new),

	void (*cleanup)(struct subprocess_info *), void *data)

{

	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_setfns(info, init, cleanup, data);



	return call_usermodehelper_exec(info, wait);

}

EXPORT_SYMBOL(call_usermodehelper_fns);



static int proc_cap_handler(struct ctl_table *table, int write,

			 void __user *buffer, size_t *lenp, loff_t *ppos)

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