eCryptfs: Write out all dirty pages just before releasing the lower file

Fixes a regression caused by:

821f749 eCryptfs: Revert to a writethrough cache model

That patch reverted some code (specifically, 32001d6f) that was
necessary to properly handle open() -> mmap() -> close() -> dirty pages
-> munmap(), because the lower file could be closed before the dirty
pages are written out.

Rather than reapplying 32001d6f, this approach is a better way of
ensuring that the lower file is still open in order to handle writing
out the dirty pages. It is called from ecryptfs_release(), while we have
a lock on the lower file pointer, just before the lower file gets the
final fput() and we overwrite the pointer.

https://launchpad.net/bugs/1047261

Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Reported-by: Artemy Tregubenko <me@arty.name>
Tested-by: Artemy Tregubenko <me@arty.name>
Tested-by: Colin Ian King <colin.king@canonical.com>
This commit is contained in:
Tyler Hicks 2012-09-12 18:02:46 -07:00
parent e9bd8f1624
commit 7149f2558d

View File

@ -162,6 +162,7 @@ void ecryptfs_put_lower_file(struct inode *inode)
inode_info = ecryptfs_inode_to_private(inode);
if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count,
&inode_info->lower_file_mutex)) {
filemap_write_and_wait(inode->i_mapping);
fput(inode_info->lower_file);
inode_info->lower_file = NULL;
mutex_unlock(&inode_info->lower_file_mutex);