[PATCH] fs/9p: Always ask new inode in lookup for cache mode disabled
DORMANTno replies
From: Aneesh Kumar K.V <hidden>
Date: 2011-08-16 16:51:04
Also in:
lkml
Subsystem:
9p file system, filesystems (vfs and infrastructure), the rest · Maintainers:
Eric Van Hensbergen, Latchesar Ionkov, Dominique Martinet, Alexander Viro, Christian Brauner, Linus Torvalds
This make sure we don't end up reusing the unlinked inode object. The ideal way is to use inode i_generation. But i_generation is not available in userspace always. Signed-off-by: Aneesh Kumar K.V <redacted> --- fs/9p/vfs_inode.c | 29 ++++++++++++++++++++++------- 1 files changed, 22 insertions(+), 7 deletions(-)
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 9e3ea6c..b2a41e5 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c@@ -40,6 +40,7 @@ #include <net/9p/9p.h> #include <net/9p/client.h> + #include "v9fs.h" #include "v9fs_vfs.h" #include "fid.h"
@@ -825,6 +826,7 @@ static int v9fs_vfs_mkdir(struct inode *dir, struct dentry *dentry, int mode) struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nameidata) { + struct dentry *res; struct super_block *sb; struct v9fs_session_info *v9ses; struct p9_fid *dfid, *fid;
@@ -856,22 +858,35 @@ struct dentry *v9fs_vfs_lookup(struct inode *dir, struct dentry *dentry, return ERR_PTR(result); } - - inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb); + /* + * Make sure we don't use a wrong inode due to parallel + * unlink. For cached mode create calls request for new + * inode. But with cache disabled, lookup should do this. + */ + if (v9ses->cache) + inode = v9fs_get_inode_from_fid(v9ses, fid, dir->i_sb); + else + inode = v9fs_get_new_inode_from_fid(v9ses, fid, dir->i_sb); if (IS_ERR(inode)) { result = PTR_ERR(inode); inode = NULL; goto error; } - result = v9fs_fid_add(dentry, fid); if (result < 0) goto error_iput; - inst_out: - d_add(dentry, inode); - return NULL; - + /* + * If we had a rename on the server and a parallel lookup + * for the new name, then make sure we instantiate with + * the new name. ie look up for a/b, while server somebody + * moved b under k and client parallely did a lookup for + * k/b. + */ + res = d_materialise_unique(dentry, inode); + if (!IS_ERR(res)) + return res; + result = PTR_ERR(res); error_iput: iput(inode); error:
--
1.7.4.1