Take the completion of automount into new helper

... and shift it from namei.c to namespace.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Take the completion of automount into new helper
... and shift it from namei.c to namespace.c Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
1 parent e78bf5e6cb
Showing 3 changed files with 39 additions and 26 deletions Side-by-side Diff
fs/internal.h
fs/namei.c
fs/namespace.c
@@ -70,6 +70,7 @@
 extern void release_mounts(struct list_head *);
 extern void umount_tree(struct vfsmount *, int, struct list_head *);
 extern struct vfsmount *copy_tree(struct vfsmount *, struct dentry *, int);
+extern int finish_automount(struct vfsmount *, struct path *);
 extern int do_add_mount(struct vfsmount *, struct path *, int);
 extern void mnt_clear_expiry(struct vfsmount *);
  
@@ -923,37 +923,13 @@
 	if (!mnt) /* mount collision */
 		return 0;
  
-	/* The new mount record should have at least 2 refs to prevent it being
-	 * expired before we get a chance to add it
-	 */
-	BUG_ON(mnt_get_count(mnt) < 2);
+	err = finish_automount(mnt, path);
  
-	if (mnt->mnt_sb == path->mnt->mnt_sb &&
-	    mnt->mnt_root == path->dentry) {
-		mnt_clear_expiry(mnt);
-		mntput(mnt);
-		mntput(mnt);
-		return -ELOOP;
-	}
-
-	/* We need to add the mountpoint to the parent.  The filesystem may
-	 * have placed it on an expiry list, and so we need to make sure it
-	 * won't be expired under us if do_add_mount() fails (do_add_mount()
-	 * will eat a reference unconditionally).
-	 */
-	mntget(mnt);
-	err = do_add_mount(mnt, path, path->mnt->mnt_flags | MNT_SHRINKABLE);
 	switch (err) {
 	case -EBUSY:
 		/* Someone else made a mount here whilst we were busy */
-		err = 0;
-	default:
-		mnt_clear_expiry(mnt);
-		mntput(mnt);
-		mntput(mnt);
-		return err;
+		return 0;
 	case 0:
-		mntput(mnt);
 		dput(path->dentry);
 		if (*need_mntput)
 			mntput(path->mnt);
  
@@ -961,7 +937,10 @@
 		path->dentry = dget(mnt->mnt_root);
 		*need_mntput = true;
 		return 0;
+	default:
+		return err;
 	}
+
 }
  
 /*
@@ -1895,6 +1895,39 @@
 	return do_add_mount(mnt, path, mnt_flags);
 }
  
+int finish_automount(struct vfsmount *m, struct path *path)
+{
+	int err;
+	/* The new mount record should have at least 2 refs to prevent it being
+	 * expired before we get a chance to add it
+	 */
+	BUG_ON(mnt_get_count(m) < 2);
+
+	if (m->mnt_sb == path->mnt->mnt_sb &&
+	    m->mnt_root == path->dentry) {
+		mnt_clear_expiry(m);
+		mntput(m);
+		mntput(m);
+		return -ELOOP;
+	}
+
+	/* We need to add the mountpoint to the parent.  The filesystem may
+	 * have placed it on an expiry list, and so we need to make sure it
+	 * won't be expired under us if do_add_mount() fails (do_add_mount()
+	 * will eat a reference unconditionally).
+	 */
+	mntget(m);
+	err = do_add_mount(m, path, path->mnt->mnt_flags | MNT_SHRINKABLE);
+	if (err) {
+		mnt_clear_expiry(m);
+		mntput(m);
+		mntput(m);
+	} else {
+		mntput(m);
+	}
+	return err;
+}
+
 /*
  * add a mount into a namespace's mount tree
  * - this unconditionally eats one of the caller's references to newmnt.
...	...	@@ -70,6 +70,7 @@
70	70	extern void release_mounts(struct list_head *);
71	71	extern void umount_tree(struct vfsmount , int, struct list_head );
72	72	extern struct vfsmount copy_tree(struct vfsmount , struct dentry *, int);
	73	+extern int finish_automount(struct vfsmount , struct path );
73	74	extern int do_add_mount(struct vfsmount , struct path , int);
74	75	extern void mnt_clear_expiry(struct vfsmount *);
75	76
...	...	@@ -923,37 +923,13 @@
923	923	if (!mnt) /* mount collision */
924	924	return 0;
925	925
926		- /* The new mount record should have at least 2 refs to prevent it being
927		- * expired before we get a chance to add it
928		- */
929		- BUG_ON(mnt_get_count(mnt) < 2);
	926	+ err = finish_automount(mnt, path);
930	927
931		- if (mnt->mnt_sb == path->mnt->mnt_sb &&
932		- mnt->mnt_root == path->dentry) {
933		- mnt_clear_expiry(mnt);
934		- mntput(mnt);
935		- mntput(mnt);
936		- return -ELOOP;
937		- }
938		-
939		- /* We need to add the mountpoint to the parent. The filesystem may
940		- * have placed it on an expiry list, and so we need to make sure it
941		- * won't be expired under us if do_add_mount() fails (do_add_mount()
942		- * will eat a reference unconditionally).
943		- */
944		- mntget(mnt);
945		- err = do_add_mount(mnt, path, path->mnt->mnt_flags \| MNT_SHRINKABLE);
946	928	switch (err) {
947	929	case -EBUSY:
948	930	/* Someone else made a mount here whilst we were busy */
949		- err = 0;
950		- default:
951		- mnt_clear_expiry(mnt);
952		- mntput(mnt);
953		- mntput(mnt);
954		- return err;
	931	+ return 0;
955	932	case 0:
956		- mntput(mnt);
957	933	dput(path->dentry);
958	934	if (*need_mntput)
959	935	mntput(path->mnt);
960	936
...	...	@@ -961,7 +937,10 @@
961	937	path->dentry = dget(mnt->mnt_root);
962	938	*need_mntput = true;
963	939	return 0;
	940	+ default:
	941	+ return err;
964	942	}
	943	+
965	944	}
966	945
967	946	/*
...	...	@@ -1895,6 +1895,39 @@
1895	1895	return do_add_mount(mnt, path, mnt_flags);
1896	1896	}
1897	1897
	1898	+int finish_automount(struct vfsmount m, struct path path)
	1899	+{
	1900	+ int err;
	1901	+ /* The new mount record should have at least 2 refs to prevent it being
	1902	+ * expired before we get a chance to add it
	1903	+ */
	1904	+ BUG_ON(mnt_get_count(m) < 2);
	1905	+
	1906	+ if (m->mnt_sb == path->mnt->mnt_sb &&
	1907	+ m->mnt_root == path->dentry) {
	1908	+ mnt_clear_expiry(m);
	1909	+ mntput(m);
	1910	+ mntput(m);
	1911	+ return -ELOOP;
	1912	+ }
	1913	+
	1914	+ /* We need to add the mountpoint to the parent. The filesystem may
	1915	+ * have placed it on an expiry list, and so we need to make sure it
	1916	+ * won't be expired under us if do_add_mount() fails (do_add_mount()
	1917	+ * will eat a reference unconditionally).
	1918	+ */
	1919	+ mntget(m);
	1920	+ err = do_add_mount(m, path, path->mnt->mnt_flags \| MNT_SHRINKABLE);
	1921	+ if (err) {
	1922	+ mnt_clear_expiry(m);
	1923	+ mntput(m);
	1924	+ mntput(m);
	1925	+ } else {
	1926	+ mntput(m);
	1927	+ }
	1928	+ return err;
	1929	+}
	1930	+
1898	1931	/*
1899	1932	* add a mount into a namespace's mount tree
1900	1933	* - this unconditionally eats one of the caller's references to newmnt.