From: J. Bruce Fields bfie...@redhat.com
There are a few d_obtain_alias callers that are using it to get the
root of a filesystem which may already have an alias somewhere else.
This is not the same as the filehandle-lookup case, and none of them
actually need DCACHE_DISCONNECTED set.
In the btrfs case this was causing a spurious printk from
nfsd/nfsfh.c:fh_verify when it found an unexpected DCACHE_DISCONNECTED
dentry.
Which isn't really a serious problem, but it would really be clearer if
we reserved DCACHE_DISCONNECTED for those cases where it's actually
needed.
Signed-off-by: J. Bruce Fields bfie...@redhat.com
---
fs/btrfs/super.c | 2 +-
fs/ceph/super.c| 2 +-
fs/dcache.c| 69 +++---
fs/nfs/getroot.c | 2 +-
fs/nilfs2/super.c | 2 +-
include/linux/dcache.h | 1 +
6 files changed, 54 insertions(+), 24 deletions(-)
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 97cc241..07ce96b 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -925,7 +925,7 @@ setup_root:
return dget(sb-s_root);
}
- return d_obtain_alias(inode);
+ return d_obtain_alias_root(inode);
}
static int btrfs_fill_super(struct super_block *sb,
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 2df963f..9666950 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -732,7 +732,7 @@ static struct dentry *open_root_dentry(struct
ceph_fs_client *fsc,
goto out;
}
} else {
- root = d_obtain_alias(inode);
+ root = d_obtain_alias_root(inode);
}
ceph_init_dentry(root);
dout(open_root_inode success, root dentry is %p\n, root);
diff --git a/fs/dcache.c b/fs/dcache.c
index e3e4618..3a1057a 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1832,25 +1832,7 @@ struct dentry *d_find_any_alias(struct inode *inode)
}
EXPORT_SYMBOL(d_find_any_alias);
-/**
- * d_obtain_alias - find or allocate a dentry for a given inode
- * @inode: inode to allocate the dentry for
- *
- * Obtain a dentry for an inode resulting from NFS filehandle conversion or
- * similar open by handle operations. The returned dentry may be anonymous,
- * or may have a full name (if the inode was already in the cache).
- *
- * When called on a directory inode, we must ensure that the inode only ever
- * has one dentry. If a dentry is found, that is returned instead of
- * allocating a new one.
- *
- * On successful return, the reference to the inode has been transferred
- * to the dentry. In case of an error the reference on the inode is released.
- * To make it easier to use in export operations a %NULL or IS_ERR inode may
- * be passed in and will be the error will be propagate to the return value,
- * with a %NULL @inode replaced by ERR_PTR(-ESTALE).
- */
-struct dentry *d_obtain_alias(struct inode *inode)
+struct dentry *__d_obtain_alias(struct inode *inode, int disconnected)
{
static const struct qstr anonstring = QSTR_INIT(/, 1);
struct dentry *tmp;
@@ -1881,7 +1863,10 @@ struct dentry *d_obtain_alias(struct inode *inode)
}
/* attach a disconnected dentry */
- add_flags = d_flags_for_inode(inode) | DCACHE_DISCONNECTED;
+ add_flags = d_flags_for_inode(inode);
+
+ if (disconnected)
+ add_flags |= DCACHE_DISCONNECTED;
spin_lock(tmp-d_lock);
tmp-d_inode = inode;
@@ -1902,9 +1887,53 @@ struct dentry *d_obtain_alias(struct inode *inode)
iput(inode);
return res;
}
+
+/**
+ * d_obtain_alias - find or allocate a DISCONNECTED dentry for a given inode
+ * @inode: inode to allocate the dentry for
+ *
+ * Obtain a dentry for an inode resulting from NFS filehandle conversion or
+ * similar open by handle operations. The returned dentry may be anonymous,
+ * or may have a full name (if the inode was already in the cache).
+ *
+ * When called on a directory inode, we must ensure that the inode only ever
+ * has one dentry. If a dentry is found, that is returned instead of
+ * allocating a new one.
+ *
+ * On successful return, the reference to the inode has been transferred
+ * to the dentry. In case of an error the reference on the inode is released.
+ * To make it easier to use in export operations a %NULL or IS_ERR inode may
+ * be passed in and the error will be propagated to the return value,
+ * with a %NULL @inode replaced by ERR_PTR(-ESTALE).
+ */
+struct dentry *d_obtain_alias(struct inode *inode)
+{
+ return __d_obtain_alias(inode, 1);
+}
EXPORT_SYMBOL(d_obtain_alias);
/**
+ * d_obtain_alias_root - find or allocate a dentry for a given inode
+ * @inode: inode to allocate the dentry for
+ *
+ * Obtain an IS_ROOT dentry for the root of a filesystem.
+ *
+ * We must ensure that directory inodes only ever have one dentry. If a
+ * dentry is found, that is returned instead of
