From 332ab16f830f59e7621ae8eb2c353dc135a316f6 Mon Sep 17 00:00:00 2001 From: Tyler Hicks Date: Thu, 14 Apr 2011 15:35:11 -0500 Subject: eCryptfs: Add reference counting to lower files For any given lower inode, eCryptfs keeps only one lower file open and multiplexes all eCryptfs file operations through that lower file. The lower file was considered "persistent" and stayed open from the first lookup through the lifetime of the inode. This patch keeps the notion of a single, per-inode lower file, but adds reference counting around the lower file so that it is closed when not currently in use. If the reference count is at 0 when an operation (such as open, create, etc.) needs to use the lower file, a new lower file is opened. Since the file is no longer persistent, all references to the term persistent file are changed to lower file. Locking is added around the sections of code that opens the lower file and assign the pointer in the inode info, as well as the code the fputs the lower file when all eCryptfs users are done with it. This patch is needed to fix issues, when mounted on top of the NFSv3 client, where the lower file is left silly renamed until the eCryptfs inode is destroyed. Signed-off-by: Tyler Hicks --- fs/ecryptfs/kthread.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/ecryptfs/kthread.c') diff --git a/fs/ecryptfs/kthread.c b/fs/ecryptfs/kthread.c index 0851ab6980f5..69f994a7d524 100644 --- a/fs/ecryptfs/kthread.c +++ b/fs/ecryptfs/kthread.c @@ -44,7 +44,7 @@ static struct task_struct *ecryptfs_kthread; * @ignored: ignored * * The eCryptfs kernel thread that has the responsibility of getting - * the lower persistent file with RW permissions. + * the lower file with RW permissions. * * Returns zero on success; non-zero otherwise */ @@ -141,8 +141,8 @@ int ecryptfs_privileged_open(struct file **lower_file, int rc = 0; /* Corresponding dput() and mntput() are done when the - * persistent file is fput() when the eCryptfs inode is - * destroyed. */ + * lower file is fput() when all eCryptfs files for the inode are + * released. */ dget(lower_dentry); mntget(lower_mnt); flags |= IS_RDONLY(lower_dentry->d_inode) ? O_RDONLY : O_RDWR; -- cgit v1.2.3