introduce kern_path_mountpoint()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

introduce kern_path_mountpoint()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
1 parent 197df04c74
Showing 2 changed files with 25 additions and 11 deletions Side-by-side Diff
fs/namei.c
include/linux/namei.h
@@ -2360,6 +2360,20 @@
 	return err;
 }
  
+static int
+filename_mountpoint(int dfd, struct filename *s, struct path *path,
+			unsigned int flags)
+{
+	int error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU);
+	if (unlikely(error == -ECHILD))
+		error = path_mountpoint(dfd, s->name, path, flags);
+	if (unlikely(error == -ESTALE))
+		error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_REVAL);
+	if (likely(!error))
+		audit_inode(s, path->dentry, 0);
+	return error;
+}
+
 /**
  * user_path_mountpoint_at - lookup a path from userland in order to umount it
  * @dfd:	directory file descriptor
  
  
@@ -2380,22 +2394,21 @@
 {
 	struct filename *s = getname(name);
 	int error;
-
 	if (IS_ERR(s))
 		return PTR_ERR(s);
-
-	error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_RCU);
-	if (unlikely(error == -ECHILD))
-		error = path_mountpoint(dfd, s->name, path, flags);
-	if (unlikely(error == -ESTALE))
-		error = path_mountpoint(dfd, s->name, path, flags | LOOKUP_REVAL);
-
-	if (likely(!error))
-		audit_inode(s, path->dentry, 0);
-
+	error = filename_mountpoint(dfd, s, path, flags);
 	putname(s);
 	return error;
 }
+
+int
+kern_path_mountpoint(int dfd, const char *name, struct path *path,
+			unsigned int flags)
+{
+	struct filename s = {.name = name};
+	return filename_mountpoint(dfd, &s, path, flags);
+}
+EXPORT_SYMBOL(kern_path_mountpoint);
  
 /*
  * It's inline, so penalty for filesystems that don't use sticky bit is
@@ -70,6 +70,7 @@
 extern struct dentry *user_path_create(int, const char __user *, struct path *, unsigned int);
 extern void done_path_create(struct path *, struct dentry *);
 extern struct dentry *kern_path_locked(const char *, struct path *);
+extern int kern_path_mountpoint(int, const char *, struct path *, unsigned int);
  
 extern struct dentry *lookup_one_len(const char *, struct dentry *, int);
...	...	@@ -2360,6 +2360,20 @@
2360	2360	return err;
2361	2361	}
2362	2362
	2363	+static int
	2364	+filename_mountpoint(int dfd, struct filename s, struct path path,
	2365	+ unsigned int flags)
	2366	+{
	2367	+ int error = path_mountpoint(dfd, s->name, path, flags \| LOOKUP_RCU);
	2368	+ if (unlikely(error == -ECHILD))
	2369	+ error = path_mountpoint(dfd, s->name, path, flags);
	2370	+ if (unlikely(error == -ESTALE))
	2371	+ error = path_mountpoint(dfd, s->name, path, flags \| LOOKUP_REVAL);
	2372	+ if (likely(!error))
	2373	+ audit_inode(s, path->dentry, 0);
	2374	+ return error;
	2375	+}
	2376	+
2363	2377	/**
2364	2378	* user_path_mountpoint_at - lookup a path from userland in order to umount it
2365	2379	* @dfd: directory file descriptor
2366	2380
2367	2381
...	...	@@ -2380,22 +2394,21 @@
2380	2394	{
2381	2395	struct filename *s = getname(name);
2382	2396	int error;
2383		-
2384	2397	if (IS_ERR(s))
2385	2398	return PTR_ERR(s);
2386		-
2387		- error = path_mountpoint(dfd, s->name, path, flags \| LOOKUP_RCU);
2388		- if (unlikely(error == -ECHILD))
2389		- error = path_mountpoint(dfd, s->name, path, flags);
2390		- if (unlikely(error == -ESTALE))
2391		- error = path_mountpoint(dfd, s->name, path, flags \| LOOKUP_REVAL);
2392		-
2393		- if (likely(!error))
2394		- audit_inode(s, path->dentry, 0);
2395		-
	2399	+ error = filename_mountpoint(dfd, s, path, flags);
2396	2400	putname(s);
2397	2401	return error;
2398	2402	}
	2403	+
	2404	+int
	2405	+kern_path_mountpoint(int dfd, const char name, struct path path,
	2406	+ unsigned int flags)
	2407	+{
	2408	+ struct filename s = {.name = name};
	2409	+ return filename_mountpoint(dfd, &s, path, flags);
	2410	+}
	2411	+EXPORT_SYMBOL(kern_path_mountpoint);
2399	2412
2400	2413	/*
2401	2414	* It's inline, so penalty for filesystems that don't use sticky bit is
...	...	@@ -70,6 +70,7 @@
70	70	extern struct dentry user_path_create(int, const char __user , struct path *, unsigned int);
71	71	extern void done_path_create(struct path , struct dentry );
72	72	extern struct dentry kern_path_locked(const char , struct path *);
	73	+extern int kern_path_mountpoint(int, const char , struct path , unsigned int);
73	74
74	75	extern struct dentry lookup_one_len(const char , struct dentry *, int);
75	76