lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

fs/9p: Fix race in initializing writeback fid

Browse Source 
When two process open the same file we can end up with both of them
allocating the writeback_fid. Add a new mutex which can be used
for synchronizing v9fs_inode member values.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
This commit is contained in:
Aneesh Kumar K.V
2011-03-08 16:39:46 +05:30
committed by Eric Van Hensbergen
parent f741a79e98
commit 5a7e0a8cf5
4 changed files with 11 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

3
fs/9p/vfs_file.c
View File

@@ -90,6 +90,7 @@ int v9fs_file_open(struct inode *inode, struct file *file)
}
file->private_data = fid;
mutex_lock(&v9inode->v_mutex);
if (v9ses->cache && !v9inode->writeback_fid) {
/*
* clone a fid and add it to writeback_fid
@@ -101,10 +102,12 @@ int v9fs_file_open(struct inode *inode, struct file *file)
fid = v9fs_writeback_fid(file->f_path.dentry);
if (IS_ERR(fid)) {
err = PTR_ERR(fid);
mutex_unlock(&v9inode->v_mutex);
goto out_error;
}
v9inode->writeback_fid = (void *) fid;
}
mutex_unlock(&v9inode->v_mutex);
#ifdef CONFIG_9P_FSCACHE
if (v9ses->cache)
v9fs_cache_inode_set_cookie(inode, file);