[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>

1 files changed, 36 insertions, 8 deletions

diff --git a/fs/ecryptfs/file.c b/fs/ecryptfs/file.c
index c8550c9f9cd2..a92ef05eff8f 100644
--- a/fs/ecryptfs/file.c
+++ b/fs/ecryptfs/file.c
@@ -198,6 +198,33 @@ retry:
 
 struct kmem_cache *ecryptfs_file_info_cache;
 
+int ecryptfs_open_lower_file(struct file **lower_file,
+                             struct dentry *lower_dentry,
+                             struct vfsmount *lower_mnt, int flags)
+{
+        int rc = 0;
+
+        dget(lower_dentry);
+        mntget(lower_mnt);
+        *lower_file = dentry_open(lower_dentry, lower_mnt, flags);
+        if (IS_ERR(*lower_file)) {
+                printk(KERN_ERR "Error opening lower file for lower_dentry "
+                       "[0x%p], lower_mnt [0x%p], and flags [0x%x]\n",
+                       lower_dentry, lower_mnt, flags);
+                rc = PTR_ERR(*lower_file);
+                *lower_file = NULL;
+                goto out;
+        }
+out:
+        return rc;
+}
+
+int ecryptfs_close_lower_file(struct file *lower_file)
+{
+        fput(lower_file);
+        return 0;
+}
+
 /**
  * ecryptfs_open
  * @inode: inode speciying file to open
@@ -244,19 +271,15 @@ static int ecryptfs_open(struct inode *inode, struct file *file)
                 ECRYPTFS_SET_FLAG(crypt_stat->flags, ECRYPTFS_ENCRYPTED);
         }
         mutex_unlock(&crypt_stat->cs_mutex);
-        /* This mntget & dget is undone via fput when the file is released */
-        dget(lower_dentry);
         lower_flags = file->f_flags;
         if ((lower_flags & O_ACCMODE) == O_WRONLY)
                 lower_flags = (lower_flags & O_ACCMODE) | O_RDWR;
         if (file->f_flags & O_APPEND)
                 lower_flags &= ~O_APPEND;
         lower_mnt = ecryptfs_dentry_to_lower_mnt(ecryptfs_dentry);
-        mntget(lower_mnt);
         /* Corresponding fput() in ecryptfs_release() */
-        lower_file = dentry_open(lower_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 lower file\n");
                 goto out_puts;
         }
@@ -341,11 +364,16 @@ static int ecryptfs_release(struct inode *inode, struct file *file)
         struct file *lower_file = ecryptfs_file_to_lower(file);
         struct ecryptfs_file_info *file_info = ecryptfs_file_to_private(file);
         struct inode *lower_inode = ecryptfs_inode_to_lower(inode);
+        int rc;
 
-        fput(lower_file);
+        if ((rc = ecryptfs_close_lower_file(lower_file))) {
+                printk(KERN_ERR "Error closing lower_file\n");
+                goto out;
+        }
         inode->i_blocks = lower_inode->i_blocks;
         kmem_cache_free(ecryptfs_file_info_cache, file_info);
-        return 0;
+out:
+        return rc;
 }
 
 static int