kclient: never use VFS-provided dentry if d_parent is incorrect

diff --git a/src/kernel/inode.c b/src/kernel/inode.c
index a489a688a828e849ce950ec54cca6a952329a886..0b8d896ef1e351edd635605c05607fc7b4ea7b1a 100644 (file)
--- a/src/kernel/inode.c
+++ b/src/kernel/inode.c
@@ -649,7 +649,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
 #endif
 
        ino = le64_to_cpu(rinfo->trace_in[0].in->ino);
-       if (dn) {
+       if (likely(dn)) {
                in = dn->d_inode;
                /* trace should start at root, or have only 1 dentry
                 * (if it is in mds stray dir) */
@@ -684,59 +684,48 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                dname.len = rinfo->trace_dname_len[d];
                parent = dn;
 
-               dout(10, "fill_trace %d/%d parent %p in %p d '%.*s'\n",
-                    (d+1), rinfo->trace_numd, parent, parent->d_inode,
-                    (int)dname.len, dname.name);
+               dout(10, "fill_trace %d/%d parent %p '%.*s' inode %p\n",
+                    (d+1), rinfo->trace_numd, parent,
+                    (int)dname.len, dname.name, parent->d_inode);
 
-               /* dentry */
+               /* existing dentry? */
                dn = 0;
+               dname.hash = full_name_hash(dname.name, dname.len);
+       retry_lookup:
+               dn = d_lookup(parent, &dname);
+               dout(10, "fill_trace d_lookup of '%.*s' got %p\n",
+                    (int)dname.len, dname.name, dn);
+               
+               /* use caller provided dentry?  for simplicity,
+                *  - only if there is no existing dn, and
+                *  - only if parent is correct
+                */
                if (d == rinfo->trace_numd-1 && req->r_last_dentry) {
-                       dn = req->r_last_dentry;
-                       dout(10, "fill_trace provided dn %p '%.*s'\n", dn,
-                            dn->d_name.len, dn->d_name.name);
-                       ceph_init_dentry(dn);  /* just in case */
-                       req->r_last_dentry = NULL;
-
-                       /* rename? */
-                       if (req->r_old_dentry) {
-                               dout(10, " src %p '%.*s' dst %p '%.*s'\n",
-                                    req->r_old_dentry,
-                                    req->r_old_dentry->d_name.len,
-                                    req->r_old_dentry->d_name.name,
-                                    dn, dn->d_name.len, dn->d_name.name);
-                               dout(10, "fill_trace doing d_move %p -> %p\n",
-                                    req->r_old_dentry, dn);
-                               d_move(req->r_old_dentry, dn);
-                               dout(10, " src %p '%.*s' dst %p '%.*s'\n",
-                                    req->r_old_dentry,
-                                    req->r_old_dentry->d_name.len,
-                                    req->r_old_dentry->d_name.name,
+                       if (!dn && req->r_last_dentry->d_parent == parent) {
+                               dn = req->r_last_dentry;
+                               dout(10, "fill_trace provided dn %p '%.*s'\n",
                                     dn, dn->d_name.len, dn->d_name.name);
-                               dput(dn);  /* dn is dropped */
-                               dn = req->r_old_dentry;  /* use old_dentry */
-                               req->r_old_dentry = 0;
+                               ceph_init_dentry(dn);  /* just in case */
+                       } else {
+                               dout(10, "fill_trace NOT using provided dn %p "
+                                    "(parent %p)\n", req->r_last_dentry,
+                                    req->r_last_dentry->d_parent);
+                               dput(req->r_last_dentry);
                        }
-                       if (dn->d_parent != parent)
-                               dout(10, "warning: d_parent %p != %p\n",
-                                    dn->d_parent, parent);
+                       req->r_last_dentry = NULL;
                }
 
                if (!dn) {
-                       dname.hash = full_name_hash(dname.name, dname.len);
-               retry_lookup:
-                       dn = d_lookup(parent, &dname);
-                       dout(10, "fill_trace d_lookup of '%.*s' got %p\n",
-                            (int)dname.len, dname.name, dn);
+                       dn = d_alloc(parent, &dname);
                        if (!dn) {
-                               dn = d_alloc(parent, &dname);
-                               if (!dn) {
-                                       derr(0, "d_alloc enomem\n");
-                                       err = -ENOMEM;
-                                       break;
-                               }
-                               ceph_init_dentry(dn);
+                               derr(0, "d_alloc enomem\n");
+                               err = -ENOMEM;
+                               break;
                        }
-               }
+                       dout(10, "fill_trace d_alloc %p '%.*s'\n", dn,
+                            dn->d_name.len, dn->d_name.name);
+                       ceph_init_dentry(dn);
+               }                               
                BUG_ON(!dn);
 
                /* null dentry? */
@@ -758,11 +747,34 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                        break;
                }
 
+               /* rename? */
+               if (d == rinfo->trace_numd-1 && req->r_old_dentry) {
+                       dout(10, " src %p '%.*s' dst %p '%.*s'\n",
+                            req->r_old_dentry,
+                            req->r_old_dentry->d_name.len,
+                            req->r_old_dentry->d_name.name,
+                            dn, dn->d_name.len, dn->d_name.name);
+                       dout(10, "fill_trace doing d_move %p -> %p\n",
+                            req->r_old_dentry, dn);
+                       d_move(req->r_old_dentry, dn);
+                       dout(10, " src %p '%.*s' dst %p '%.*s'\n",
+                            req->r_old_dentry,
+                            req->r_old_dentry->d_name.len,
+                            req->r_old_dentry->d_name.name,
+                            dn, dn->d_name.len, dn->d_name.name);
+                       dput(dn);  /* dn is dropped */
+                       dn = req->r_old_dentry;  /* use old_dentry */
+                       req->r_old_dentry = 0;
+               }
+               if (dn->d_parent != parent)
+                       dout(10, "warning: d_parent %p != %p\n",
+                            dn->d_parent, parent);
+
                /* attach proper inode */
                ininfo = rinfo->trace_in[d+1].in;
                if (dn->d_inode) {
                        if (ceph_ino(dn->d_inode) != le64_to_cpu(ininfo->ino)) {
-                               dout(10, "dn %p wrong %p ino %llx\n",
+                               dout(10, "dn %p wrong inode %p ino %llx\n",
                                     dn, dn->d_inode, ceph_ino(dn->d_inode));
                                d_delete(dn);
                                dput(dn);
@@ -801,13 +813,10 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
                                dout(10, "dn %p attached to %p ino %llx\n",
                                     dn, dn->d_inode, ceph_ino(dn->d_inode));
                }
-               if (dn->d_parent == parent)
-                       ceph_update_dentry_lease(dn, rinfo->trace_dlease[d],
-                                                session, req->r_from_time);
-               else
-                       derr(10, "sloppy tailing dentry %p, not doing lease\n",
-                            dn);
+               BUG_ON(dn->d_parent != parent);
 
+               ceph_update_dentry_lease(dn, rinfo->trace_dlease[d],
+                                        session, req->r_from_time);
                err = ceph_fill_inode(in,
                                      &rinfo->trace_in[d+1],
                                      rinfo->trace_numd <= d ?