[RFC PATCH v4 02/12] kmod - rename call_usermodehelper() flags parameter

[Ian Kent <raven@themaw.net>]

From: Ian Kent <ikent@redhat.com>

The wait parameter of call_usermodehelper() is not quite a parameter
that describes the wait behaviour alone and will later be used to
request execution within the current namespaces. This flag is tied
to the wait field of the subprocess_info structure which is also
a field that doesn't specify wait behaviour alone and is used to
hold the passed flags information.

So change both the parameter and structure field name to flags.

Signed-off-by: Ian Kent <ikent@redhat.com>
Cc: Benjamin Coddington <bcodding@redhat.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Oleg Nesterov <onestero@redhat.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Jeff Layton <jeff.layton@primarydata.com>
---
 include/linux/kmod.h |    6 +++---
 kernel/kmod.c        |   32 +++++++++++++++++---------------
 2 files changed, 20 insertions(+), 18 deletions(-)

diff --git a/include/linux/kmod.h b/include/linux/kmod.h
index 0555cc6..e647ddb 100644
--- a/include/linux/kmod.h
+++ b/include/linux/kmod.h
@@ -59,7 +59,7 @@ struct subprocess_info {
 	char *path;
 	char **argv;
 	char **envp;
-	int wait;
+	unsigned int flags;
 	int retval;
 	int (*init)(struct subprocess_info *info, struct cred *new);
 	void (*cleanup)(struct subprocess_info *info);
@@ -67,7 +67,7 @@ struct subprocess_info {
 };
 
 extern int
-call_usermodehelper(char *path, char **argv, char **envp, int wait);
+call_usermodehelper(char *path, char **argv, char **envp, unsigned int flags);
 
 extern struct subprocess_info *
 call_usermodehelper_setup(char *path, char **argv, char **envp, gfp_t gfp_mask,
@@ -75,7 +75,7 @@ call_usermodehelper_setup(char *path, char **argv, char **envp, gfp_t gfp_mask,
 			  void (*cleanup)(struct subprocess_info *), void *data);
 
 extern int
-call_usermodehelper_exec(struct subprocess_info *info, int wait);
+call_usermodehelper_exec(struct subprocess_info *info, unsigned int flags);
 
 extern struct ctl_table usermodehelper_table[];
 
diff --git a/kernel/kmod.c b/kernel/kmod.c
index 2777f40..e968e2d 100644
--- a/kernel/kmod.c
+++ b/kernel/kmod.c
@@ -259,7 +259,7 @@ static int ____call_usermodehelper(void *data)
 out:
 	sub_info->retval = retval;
 	/* wait_for_helper() will call umh_complete if UHM_WAIT_PROC. */
-	if (!(sub_info->wait & UMH_WAIT_PROC))
+	if (!(sub_info->flags & UMH_WAIT_PROC))
 		umh_complete(sub_info);
 	if (!retval)
 		return 0;
@@ -310,7 +310,7 @@ static void __call_usermodehelper(struct work_struct *work)
 		container_of(work, struct subprocess_info, work);
 	pid_t pid;
 
-	if (sub_info->wait & UMH_WAIT_PROC)
+	if (sub_info->flags & UMH_WAIT_PROC)
 		pid = kernel_thread(wait_for_helper, sub_info,
 				    CLONE_FS | CLONE_FILES | SIGCHLD);
 	else
@@ -525,16 +525,17 @@ EXPORT_SYMBOL(call_usermodehelper_setup);
 /**
  * call_usermodehelper_exec - start a usermode application
  * @sub_info: information about the subprocessa
- * @wait: wait for the application to finish and return status.
- *        when UMH_NO_WAIT don't wait at all, but you get no useful error back
- *        when the program couldn't be exec'ed. This makes it safe to call
- *        from interrupt context.
+ * @flags: flag to indicate whether to wait for the application to finish
+ * 	  and return status. If UMH_NO_WAIT is set don't wait at all, but
+ * 	  you get no useful error back when the program couldn't be exec'ed.
+ * 	  This makes it safe to call from interrupt context.
  *
  * Runs a user-space application.  The application is started
  * asynchronously if wait is not set, and runs as a child of keventd.
  * (ie. it runs with full root capabilities).
  */
-int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
+int call_usermodehelper_exec(struct subprocess_info *sub_info,
+			     unsigned int flags)
 {
 	DECLARE_COMPLETION_ONSTACK(done);
 	int retval = 0;
@@ -553,14 +554,14 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
 	 * This makes it possible to use umh_complete to free
 	 * the data structure in case of UMH_NO_WAIT.
 	 */
-	sub_info->complete = (wait == UMH_NO_WAIT) ? NULL : &done;
-	sub_info->wait = wait;
+	sub_info->complete = (flags & UMH_NO_WAIT) ? NULL : &done;
+	sub_info->flags = flags;
 
 	queue_work(khelper_wq, &sub_info->work);
-	if (wait == UMH_NO_WAIT)	/* task has freed sub_info */
+	if (flags & UMH_NO_WAIT)	/* task has freed sub_info */
 		goto unlock;
 
-	if (wait & UMH_KILLABLE) {
+	if (flags & UMH_KILLABLE) {
 		retval = wait_for_completion_killable(&done);
 		if (!retval)
 			goto wait_done;
@@ -587,7 +588,7 @@ EXPORT_SYMBOL(call_usermodehelper_exec);
  * @path: path to usermode executable
  * @argv: arg vector for process
  * @envp: environment for process
- * @wait: wait for the application to finish and return status.
+ * @flags: wait for the application to finish and return status.
  *        when UMH_NO_WAIT don't wait at all, but you get no useful error back
  *        when the program couldn't be exec'ed. This makes it safe to call
  *        from interrupt context.
@@ -595,17 +596,18 @@ EXPORT_SYMBOL(call_usermodehelper_exec);
  * This function is the equivalent to use call_usermodehelper_setup() and
  * call_usermodehelper_exec().
  */
-int call_usermodehelper(char *path, char **argv, char **envp, int wait)
+int call_usermodehelper(char *path,
+			char **argv, char **envp, unsigned int flags)
 {
 	struct subprocess_info *info;
-	gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
+	gfp_t gfp_mask = (flags & UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
 
 	info = call_usermodehelper_setup(path, argv, envp, gfp_mask,
 					 NULL, NULL, NULL);
 	if (info == NULL)
 		return -ENOMEM;
 
-	return call_usermodehelper_exec(info, wait);
+	return call_usermodehelper_exec(info, flags);
 }
 EXPORT_SYMBOL(call_usermodehelper);