static int au_h_verify_dentry(struct dentry *h_dentry, struct dentry *h_parent,
struct au_branch *br)
{
int err;
struct au_iattr ia;
struct inode *h_inode;
struct dentry *h_d;
struct super_block *h_sb;
err = 0;
memset(&ia, -1, sizeof(ia));
h_sb = h_dentry->d_sb;
h_inode = NULL;
if (d_is_positive(h_dentry)) {
h_inode = d_inode(h_dentry);
au_iattr_save(&ia, h_inode);
} else if (au_test_nfs(h_sb) || au_test_fuse(h_sb))
/* nfs d_revalidate may return 0 for negative dentry */
/* fuse d_revalidate always return 0 for negative dentry */
goto out;
/* main purpose is namei.c:cached_lookup() and d_revalidate */
h_d = vfsub_lkup_one(&h_dentry->d_name, h_parent);
err = PTR_ERR(h_d);
if (IS_ERR(h_d))
goto out;
err = 0;
if (unlikely(h_d != h_dentry
|| d_inode(h_d) != h_inode
|| (h_inode && au_iattr_test(&ia, h_inode))))
err = au_busy_or_stale();
dput(h_d);
out:
AuTraceErr(err);
return err;
}
/*
* simple tests for the adding inode operations.
* following the checks in vfs, plus the parent-child relationship.
*/
int au_may_add(struct dentry *dentry, aufs_bindex_t bindex,
struct dentry *h_parent, int isdir, struct au_ndx *ndx)
{
int err, exist;
struct dentry *h_dentry;
struct inode *h_inode;
umode_t h_mode;
LKTRTrace("%.*s/%.*s, b%d, dir %d\n",
AuDLNPair(h_parent), AuDLNPair(dentry), bindex, isdir);
exist = !!dentry->d_inode;
h_dentry = au_h_dptr(dentry, bindex);
h_inode = h_dentry->d_inode;
if (!exist) {
err = -EEXIST;
if (unlikely(h_inode))
goto out;
} else {
/* rename(2) case */
err = -EIO;
if (unlikely(!h_inode || !h_inode->i_nlink))
goto out;
h_mode = h_inode->i_mode;
if (!isdir) {
err = -EISDIR;
if (unlikely(S_ISDIR(h_mode)))
goto out;
} else if (unlikely(!S_ISDIR(h_mode))) {
err = -ENOTDIR;
goto out;
}
}
err = -EIO;
/* expected parent dir is locked */
if (unlikely(h_parent != h_dentry->d_parent))
goto out;
err = 0;
if (au_opt_test(au_mntflags(dentry->d_sb), UDBA_INOTIFY)) {
struct dentry *h_latest;
struct qstr *qstr = &dentry->d_name;
err = -EACCES;
if (unlikely(au_test_h_perm
(h_parent->d_inode, MAY_EXEC | MAY_WRITE,
au_ftest_ndx(ndx->flags, DLGT))))
goto out;
h_latest = au_sio_lkup_one(qstr->name, h_parent, qstr->len,
ndx);
err = PTR_ERR(h_latest);
if (IS_ERR(h_latest))
goto out;
err = -EIO;
dput(h_latest);
/* fuse d_revalidate always return 0 for negative dentries */
if (h_latest == h_dentry || au_test_fuse(h_dentry->d_sb))
err = 0;
}
out:
AuTraceErr(err);
return err;
}
