svn commit: r216691 - head/sys/fs/nfsserver

[Rick Macklem]

Author: rmacklem
Date: Fri Dec 24 18:46:44 2010
New Revision: 216691
URL: http://svn.freebsd.org/changeset/base/216691

Log:
  Since VOP_READDIR() for ZFS does not return monotonically
  increasing directory offset cookies, disable the UFS related
  loop that skips over directory entries at the beginning of
  the block for the experimental NFS server. This loop is
  required for UFS since it always returns directory entries
  starting at the beginning of the block that
  the requested directory offset is in. In discussion with pjd@
  and mckusick@ it seems that this behaviour of UFS should maybe
  change, with this fix being an interim patch until then.
  This patch only fixes the experimental server, since pjd@ is
  working on a patch for the regular server.
  
  Discussed with:	pjd, mckusick
  MFC after:	5 days

Modified:
  head/sys/fs/nfsserver/nfs_nfsdport.c

Modified: head/sys/fs/nfsserver/nfs_nfsdport.c
==============================================================================
--- head/sys/fs/nfsserver/nfs_nfsdport.c	Fri Dec 24 15:36:12 2010	(r216690)
+++ head/sys/fs/nfsserver/nfs_nfsdport.c	Fri Dec 24 18:46:44 2010	(r216691)
@@ -1432,6 +1432,7 @@ nfsrvd_readdir(struct nfsrv_descript *nd
 	u_long *cookies = NULL, *cookiep;
 	struct uio io;
 	struct iovec iv;
+	int not_zfs;
 
 	if (nd->nd_repstat) {
 		nfsrv_postopattr(nd, getret, &at);
@@ -1484,6 +1485,7 @@ nfsrvd_readdir(struct nfsrv_descript *nd
 			nfsrv_postopattr(nd, getret, &at);
 		return (0);
 	}
+	not_zfs = strcmp(vp->v_mount->mnt_vfc->vfc_name, "zfs");
 	NFSVOPUNLOCK(vp, 0, p);
 	MALLOC(rbuf, caddr_t, siz, M_TEMP, M_WAITOK);
 again:
@@ -1566,10 +1568,12 @@ again:
 	 * skip over the records that precede the requested offset. This
 	 * requires the assumption that file offset cookies monotonically
 	 * increase.
+	 * Since the offset cookies don't monotonically increase for ZFS,
+	 * this is not done when ZFS is the file system.
 	 */
 	while (cpos < cend && ncookies > 0 &&
 	    (dp->d_fileno == 0 || dp->d_type == DT_WHT ||
-	     ((u_quad_t)(*cookiep)) <= toff)) {
+	     (not_zfs != 0 && ((u_quad_t)(*cookiep)) <= toff))) {
 		cpos += dp->d_reclen;
 		dp = (struct dirent *)cpos;
 		cookiep++;
@@ -1678,6 +1682,7 @@ nfsrvd_readdirplus(struct nfsrv_descript
 	struct uio io;
 	struct iovec iv;
 	struct componentname cn;
+	int not_zfs;
 
 	if (nd->nd_repstat) {
 		nfsrv_postopattr(nd, getret, &at);
@@ -1755,6 +1760,7 @@ nfsrvd_readdirplus(struct nfsrv_descript
 			nfsrv_postopattr(nd, getret, &at);
 		return (0);
 	}
+	not_zfs = strcmp(vp->v_mount->mnt_vfc->vfc_name, "zfs");
 
 	MALLOC(rbuf, caddr_t, siz, M_TEMP, M_WAITOK);
 again:
@@ -1827,10 +1833,12 @@ again:
 	 * skip over the records that precede the requested offset. This
 	 * requires the assumption that file offset cookies monotonically
 	 * increase.
+	 * Since the offset cookies don't monotonically increase for ZFS,
+	 * this is not done when ZFS is the file system.
 	 */
 	while (cpos < cend && ncookies > 0 &&
 	  (dp->d_fileno == 0 || dp->d_type == DT_WHT ||
-	   ((u_quad_t)(*cookiep)) <= toff ||
+	   (not_zfs != 0 && ((u_quad_t)(*cookiep)) <= toff) ||
 	   ((nd->nd_flag & ND_NFSV4) &&
 	    ((dp->d_namlen == 1 && dp->d_name[0] == '.') ||
 	     (dp->d_namlen==2 && dp->d_name[0]=='.' && dp->d_name[1]=='.'))))) {