am-utils-6.2 - add NFSv3 nfs_quick_reply() functionality

From: Ian Kent <raven@themaw.net>

The implementation of the NFS v3 server does not use the hack needed
by the nfs_quick_reply() function.

Now that saving the current transort for later use by nfs_quick_reply()
avoids concurrency races it should be ok to use it.

Signed-off-by: Ian Kent <raven@themaw.net>
---
 amd/nfs_prot_svc.c |   13 +++++
 amd/nfs_subr.c     |  137 +++++++++++++++++++++++++++++++++++++++++-----------
 2 files changed, 120 insertions(+), 30 deletions(-)

diff --git a/amd/nfs_prot_svc.c b/amd/nfs_prot_svc.c
index cbde172..29b7551 100644
--- a/amd/nfs_prot_svc.c
+++ b/amd/nfs_prot_svc.c
@@ -180,7 +180,7 @@ nfs_program_2(struct svc_req *rqstp, SVCXPRT *transp)
     xdr_result = (xdrproc_t) xdr_diropres;
     local = (nfssvcproc_t) nfsproc_lookup_2_svc;
     /*
-     * Cheap way to pass transp down to amfs_auto_lookuppn so it can
+     * Cheap way to pass transp down to amfs_auto_lookup so it can
      * be stored in the am_node structure and later used for
      * quick_reply().
      */
@@ -327,6 +327,8 @@ nfs_program_3(struct svc_req *rqstp, register SVCXPRT *transp)
   xdrproc_t _xdr_argument, _xdr_result;
   nfssvcproc_t local;
 
+  current_transp = NULL;
+
   switch (rqstp->rq_proc) {
   case AM_NFS3_NULL:
     _xdr_argument = (xdrproc_t) xdr_void;
@@ -350,6 +352,12 @@ nfs_program_3(struct svc_req *rqstp, register SVCXPRT *transp)
     _xdr_argument = (xdrproc_t) xdr_am_LOOKUP3args;
     _xdr_result = (xdrproc_t) xdr_am_LOOKUP3res;
     local = (nfssvcproc_t) (char *(*)(char *, struct svc_req *)) am_nfs3_lookup_3_svc;
+    /*
+     * Cheap way to pass transp down to amfs_auto_lookup so it can
+     * be stored in the am_node structure and later used for
+     * quick_reply().
+     */
+    current_transp = transp;
     break;
 
   case AM_NFS3_ACCESS:
@@ -476,6 +484,9 @@ nfs_program_3(struct svc_req *rqstp, register SVCXPRT *transp)
   }
 
   result = (*local) (&argument, rqstp);
+
+  current_transp = NULL;
+
   if (result != NULL && !svc_sendreply(transp, (xdrproc_t) _xdr_result, result)) {
     svcerr_systemerr (transp);
   }
diff --git a/amd/nfs_subr.c b/amd/nfs_subr.c
index 07d960d..a383618 100644
--- a/amd/nfs_subr.c
+++ b/amd/nfs_subr.c
@@ -87,6 +87,9 @@ struct am_fh3 {
 };
 
 /* forward declarations */
+static int nfs_quick_reply2(am_node *mp, int error);
+static int nfs_quick_reply3(am_node *mp, int error);
+
 /* converting am-filehandles to mount-points */
 static am_node *fh_to_mp3(am_nfs_fh *fhp, int *rp, int vop);
 static am_node *fh_to_mp(am_nfs_fh *fhp);
@@ -255,46 +258,65 @@ nfsproc_lookup_2_svc(nfsdiropargs *argp, struct svc_req *rqstp)
   return &res;
 }
 
-
 void
 nfs_quick_reply(am_node *mp, int error)
 {
-  SVCXPRT *transp = mp->am_transp;
-  nfsdiropres res;
-  xdrproc_t xdr_result = (xdrproc_t) xdr_diropres;
+  int ret;
 
   /*
-   * If there's a transp structure then we can reply to the client's
-   * nfs lookup request.
+   * If there's no transp structure then we can't reply to the
+   * client's nfs lookup request.
    */
-  if (transp) {
-    if (error == 0) {
-      /*
-       * Construct a valid reply to a lookup request.  Same
-       * code as in nfsproc_lookup_2_svc() above.
-       */
-      mp_to_fh(mp, &res.dr_u.dr_drok_u.drok_fhandle);
-      res.dr_u.dr_drok_u.drok_attributes = mp->am_fattr;
-      res.dr_status = NFS_OK;
-    } else
-      /*
-       * Return the error that was passed to us.
-       */
-      res.dr_status = nfs_error(error);
+  if (!mp->am_transp)
+    return;
+
+  if (nfs_dispatcher == nfs_program_2)
+    ret = nfs_quick_reply2(mp, error);
+  else
+    ret = nfs_quick_reply3(mp, error);
+
+  if (!ret)
+    svcerr_systemerr(mp->am_transp);
+
+  /*
+   * Free up transp.  It's only used for one reply.
+   */
+  put_nfs_xprt(mp->am_transp);
+  mp->am_transp = NULL;
+  dlog("Quick reply sent for %s", mp->am_al->al_mnt->mf_mount);
+}
 
+
+static int
+nfs_quick_reply2(am_node *mp, int error)
+{
+  SVCXPRT *transp = mp->am_transp;
+  nfsdiropres res;
+  xdrproc_t xdr_result = (xdrproc_t) xdr_diropres;
+  int ret;
+
+  if (error == 0) {
     /*
-     * Send off our reply
+     * Construct a valid reply to a lookup request.  Same
+     * code as in nfsproc_lookup_2_svc() above.
      */
-    if (!svc_sendreply(transp, (XDRPROC_T_TYPE) xdr_result, (SVC_IN_ARG_TYPE) & res))
-      svcerr_systemerr(transp);
-
+    mp_to_fh(mp, &res.dr_u.dr_drok_u.drok_fhandle);
+    res.dr_u.dr_drok_u.drok_attributes = mp->am_fattr;
+    res.dr_status = NFS_OK;
+  } else
     /*
-     * Free up transp.  It's only used for one reply.
+     * Return the error that was passed to us.
      */
-    put_nfs_xprt(mp->am_transp);
-    mp->am_transp = NULL;
-    dlog("Quick reply sent for %s", mp->am_al->al_mnt->mf_mount);
-  }
+    res.dr_status = nfs_error(error);
+
+  /*
+   * Send off our reply
+   */
+  ret = svc_sendreply(transp,
+                     (XDRPROC_T_TYPE) xdr_result,
+                     (SVC_IN_ARG_TYPE) & res);
+
+  return ret;
 }
 
 
@@ -890,6 +912,8 @@ mp_to_fh(am_node *mp, am_nfs_fh *fhp)
     /* dlog("mp_to_fh: old filehandle: %d", fp->u.s.fhh_id); */
   }
 }
+
+
 void
 mp_to_fh3(am_node *mp, am_nfs_fh3 *fhp)
 {
@@ -1257,6 +1281,61 @@ am_nfs3_lookup_3_svc(am_LOOKUP3args *argp, struct svc_req *rqstp)
   return &result;
 }
 
+
+static int
+nfs_quick_reply3(am_node *mp, int error)
+{
+  SVCXPRT *transp = mp->am_transp;
+  xdrproc_t xdr_result = (xdrproc_t) xdr_am_LOOKUP3res;
+  am_LOOKUP3res  result;
+  am_post_op_attr *post_op_dir;
+  am_post_op_attr *post_op_obj;
+  int ret;
+
+  if (error) {
+    /*
+     * Return the error that was passed to us.
+     */
+    post_op_dir->attributes_follow = 0;
+    result.status = nfs_error(error);
+  } else {
+    post_op_dir = &result.res_u.ok.dir_attributes;
+    post_op_obj = &result.res_u.ok.obj_attributes;
+    am_fattr3 *fattr3;
+    nfsfattr *fattr;
+
+    /*
+     * Construct a valid reply to a lookup request.  Same
+     * code as in am_nfs3_lookup_3_svc() above.
+     */
+
+    /* dir attributes */
+    post_op_dir->attributes_follow = 1;
+    fattr3 = &post_op_dir->am_post_op_attr_u.attributes;
+    parent_fattr_to_fattr3(mp, fattr3);
+
+    mp_to_fh3(mp, &result.res_u.ok.object);
+
+    /* mount attributes */
+    post_op_obj->attributes_follow = 1;
+    fattr = &mp->am_fattr;
+    fattr3 = &post_op_obj->am_post_op_attr_u.attributes;
+    fattr_to_fattr3(fattr, fattr3);
+
+    result.status = AM_NFS3_OK;
+  }
+
+  /*
+   * Send off our reply
+   */
+  ret = svc_sendreply(transp,
+                     (XDRPROC_T_TYPE) xdr_result,
+                     (SVC_IN_ARG_TYPE) &result);
+
+  return ret;
+}
+
+
 am_ACCESS3res *
 am_nfs3_access_3_svc(am_ACCESS3args *argp, struct svc_req *rqstp)
 {