[PATCH] eCryptfs: Consolidate lower dentry_open's

Opens on lower dentry objects happen in several places in eCryptfs, and they
all involve the same steps (dget, mntget, dentry_open).  This patch
consolidates the lower open events into a single function call.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index efdd2b7..2f2c6cf 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -231,7 +231,6 @@
 	int lower_flags;
 	struct ecryptfs_crypt_stat *crypt_stat;
 	struct dentry *lower_dentry;
-	struct dentry *tlower_dentry = NULL;
 	struct file *lower_file;
 	struct inode *inode, *lower_inode;
 	struct vfsmount *lower_mnt;
@@ -241,30 +240,19 @@
 			lower_dentry->d_name.name);
 	inode = ecryptfs_dentry->d_inode;
 	crypt_stat = &ecryptfs_inode_to_private(inode)->crypt_stat;
-	tlower_dentry = dget(lower_dentry);
-	if (!tlower_dentry) {
-		rc = -ENOMEM;
-		ecryptfs_printk(KERN_ERR, "Error dget'ing lower_dentry\n");
-		goto out;
-	}
 	lower_flags = ((O_CREAT | O_WRONLY | O_TRUNC) & O_ACCMODE) | O_RDWR;
 #if BITS_PER_LONG != 32
 	lower_flags |= O_LARGEFILE;
 #endif
 	lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
-	mntget(lower_mnt);
 	/* Corresponding fput() at end of this function */
-	lower_file = dentry_open(tlower_dentry, lower_mnt, lower_flags);
-	if (IS_ERR(lower_file)) {
-		rc = PTR_ERR(lower_file);
+	if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
+					   lower_flags))) {
 		ecryptfs_printk(KERN_ERR,
 				"Error opening dentry; rc = [%i]\n", rc);
 		goto out;
 	}
-	/* fput(lower_file) should handle the puts if we do this */
-	lower_file->f_dentry = tlower_dentry;
-	lower_file->f_vfsmnt = lower_mnt;
-	lower_inode = tlower_dentry->d_inode;
+	lower_inode = lower_dentry->d_inode;
 	if (S_ISDIR(ecryptfs_dentry->d_inode->i_mode)) {
 		ecryptfs_printk(KERN_DEBUG, "This is a directory\n");
 		ECRYPTFS_CLEAR_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
@@ -285,7 +273,8 @@
 	}
 	rc = grow_file(ecryptfs_dentry, lower_file, inode, lower_inode);
 out_fput:
-	fput(lower_file);
+	if ((rc = ecryptfs_close_lower_file(lower_file)))
+		printk(KERN_ERR "Error closing lower_file\n");
 out:
 	return rc;
 }
@@ -832,12 +821,11 @@
 	}
 	lower_dentry = ecryptfs_dentry_to_lower(dentry);
 	/* This dget & mntget is released through fput at out_fput: */
-	dget(lower_dentry);
 	lower_mnt = ecryptfs_dentry_to_lower_mnt(dentry);
-	mntget(lower_mnt);
-	lower_file = dentry_open(lower_dentry, lower_mnt, O_RDWR);
-	if (unlikely(IS_ERR(lower_file))) {
-		rc = PTR_ERR(lower_file);
+	if ((rc = ecryptfs_open_lower_file(&lower_file, lower_dentry, lower_mnt,
+					   O_RDWR))) {
+		ecryptfs_printk(KERN_ERR,
+				"Error opening dentry; rc = [%i]\n", rc);
 		goto out_free;
 	}
 	ecryptfs_set_file_lower(&fake_ecryptfs_file, lower_file);
@@ -879,7 +867,8 @@
 		= CURRENT_TIME;
 	mark_inode_dirty_sync(inode);
 out_fput:
-	fput(lower_file);
+	if ((rc = ecryptfs_close_lower_file(lower_file)))
+		printk(KERN_ERR "Error closing lower_file\n");
 out_free:
 	if (ecryptfs_file_to_private(&fake_ecryptfs_file))
 		kmem_cache_free(ecryptfs_file_info_cache,