kclient: handle partial trace responses

diff --git a/src/kernel/inode.c b/src/kernel/inode.c
index 555b21d75136996990d71a0ab4344e5255ddbbc1..e34faeae479c74252aabf3727b6290100afa94bb 100644 (file)
--- a/src/kernel/inode.c
+++ b/src/kernel/inode.c
@@ -756,7 +756,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
        struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
        int err = 0;
        struct qstr dname;
-       struct dentry *dn = sb->s_root;
+       struct dentry *dn;
        struct dentry *parent = NULL;
        struct dentry *existing;
        struct inode *in;
@@ -797,39 +797,33 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
 
        vino.ino = le64_to_cpu(rinfo->trace_in[0].in->ino);
        vino.snap = le64_to_cpu(rinfo->trace_in[0].in->snapid);
-       if (likely(dn)) {
-               in = dn->d_inode;
-               /* trace should start at root, or have only 1 dentry
-                * (if it is in an mds stray dir) */
-               WARN_ON(vino.ino != CEPH_INO_ROOT && rinfo->trace_numd != 1);
+       in = ceph_get_inode(sb, vino);
+       if (IS_ERR(in))
+               return PTR_ERR(in);
+
+       err = fill_inode(in, &rinfo->trace_in[0],
+                        rinfo->trace_numd ?
+                        rinfo->trace_dir[0] : NULL,
+                        session, req->r_request_started,
+                        (rinfo->trace_numd == 0 &&
+                         le32_to_cpu(rinfo->head->result) == 0) ?
+                        req->r_fmode : -1);
+       if (err < 0)
+               return err;
+
+       if (likely(sb->s_root)) {
+               dn = d_find_alias(in);
        } else {
                /* first reply (i.e. we just mounted) */
-               in = ceph_get_inode(sb, vino);
-               if (IS_ERR(in))
-                       return PTR_ERR(in);
                dn = d_alloc_root(in);
                if (dn == NULL) {
                        derr(0, "d_alloc_root ENOMEM badness on root dentry\n");
                        return -ENOMEM;
                }
-       }
-
-       if (vino.ino == CEPH_INO_ROOT) {
-               err = fill_inode(in, &rinfo->trace_in[0],
-                                rinfo->trace_numd ?
-                                rinfo->trace_dir[0] : NULL,
-                                session, req->r_request_started,
-                                (rinfo->trace_numd == 0 &&
-                                 le32_to_cpu(rinfo->head->result) == 0) ?
-                                req->r_fmode : -1);
-               if (err < 0)
-                       return err;
-               if (unlikely(sb->s_root == NULL))
-                       sb->s_root = dn;
+               sb->s_root = dget(dn);
        }
 
        have_lease = 0;
-       dget(dn);
        for (d = 0; d < rinfo->trace_numd; d++) {
                dname.name = rinfo->trace_dname[d];
                dname.len = rinfo->trace_dname_len[d];