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| author | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2011-03-08 12:09:46 +0100 |
|---|---|---|
| committer | Eric Van Hensbergen <ericvh@gmail.com> | 2011-03-22 21:43:35 +0100 |
| commit | 5a7e0a8cf50cf905403f5a498e86d1f97cfcf51b (patch) | |
| tree | 3f20f98db76f7a221f397630a03e6089c1208510 /fs/9p/vfs_inode.c | |
| parent | Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/msz... (diff) | |
| download | linux-5a7e0a8cf50cf905403f5a498e86d1f97cfcf51b.tar.xz linux-5a7e0a8cf50cf905403f5a498e86d1f97cfcf51b.zip | |
fs/9p: Fix race in initializing writeback fid
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>
Diffstat (limited to 'fs/9p/vfs_inode.c')
| -rw-r--r-- | fs/9p/vfs_inode.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c index 8a2c232f708a..c6cef2495f00 100644 --- a/fs/9p/vfs_inode.c +++ b/fs/9p/vfs_inode.c @@ -221,6 +221,7 @@ struct inode *v9fs_alloc_inode(struct super_block *sb) #endif v9inode->writeback_fid = NULL; v9inode->cache_validity = 0; + mutex_init(&v9inode->v_mutex); return &v9inode->vfs_inode; } @@ -650,6 +651,7 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode, /* if we are opening a file, assign the open fid to the file */ if (nd && nd->flags & LOOKUP_OPEN) { v9inode = V9FS_I(dentry->d_inode); + mutex_lock(&v9inode->v_mutex); if (v9ses->cache && !v9inode->writeback_fid) { /* * clone a fid and add it to writeback_fid @@ -661,10 +663,12 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode, inode_fid = v9fs_writeback_fid(dentry); if (IS_ERR(inode_fid)) { err = PTR_ERR(inode_fid); + mutex_unlock(&v9inode->v_mutex); goto error; } v9inode->writeback_fid = (void *) inode_fid; } + mutex_unlock(&v9inode->v_mutex); filp = lookup_instantiate_filp(nd, dentry, generic_file_open); if (IS_ERR(filp)) { err = PTR_ERR(filp); |