fs/9p: Always ask new inode in lookup for cache mode disabled

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 <aneesh.kumar@linux.vnet.ibm.com>
This commit is contained in:
Aneesh Kumar K.V 2011-08-16 22:19:28 +05:30 committed by Eric Van Hensbergen
parent f88657ce3f
commit 73f507171c
1 changed files with 21 additions and 7 deletions

View File

@ -825,6 +825,7 @@ 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 +857,35 @@ 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 on 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: