4 files changed, 37 insertions, 2 deletions

diff --git a/sys/fs/nfsclient/nfs_clnfsiod.c b/sys/fs/nfsclient/nfs_clnfsiod.c
index 0f1810f..25ff694 100644
--- a/sys/fs/nfsclient/nfs_clnfsiod.c
+++ b/sys/fs/nfsclient/nfs_clnfsiod.c
@@ -304,6 +304,14 @@ nfssvc_iod(void *instance)
 		}
 		mtx_lock(&ncl_iod_mutex);
 		/*
+		 * Make sure the nmp hasn't been dismounted as soon as
+		 * ncl_doio() completes for the last buffer.
+		 */
+		nmp = ncl_iodmount[myiod];
+		if (nmp == NULL)
+			break;
+
+		/*
 		 * If there are more than one iod on this mount, then defect
 		 * so that the iods can be shared out fairly between the mounts
 		 */
diff --git a/sys/fs/nfsclient/nfs_clvfsops.c b/sys/fs/nfsclient/nfs_clvfsops.c
index 281ce44..b717210 100644
--- a/sys/fs/nfsclient/nfs_clvfsops.c
+++ b/sys/fs/nfsclient/nfs_clvfsops.c
@@ -81,6 +81,9 @@ extern struct timeval nfsboottime;
 extern struct nfsstats	newnfsstats;
 extern int nfsrv_useacl;
 extern int nfscl_debuglevel;
+extern enum nfsiod_state ncl_iodwant[NFS_MAXASYNCDAEMON];
+extern struct nfsmount *ncl_iodmount[NFS_MAXASYNCDAEMON];
+extern struct mtx ncl_iod_mutex;
 NFSCLSTATEMUTEX;
 
 MALLOC_DEFINE(M_NEWNFSREQ, "newnfsclient_req", "New NFS request header");
@@ -1472,7 +1475,7 @@ nfs_unmount(struct mount *mp, int mntflags)
 {
 	struct thread *td;
 	struct nfsmount *nmp;
-	int error, flags = 0, trycnt = 0;
+	int error, flags = 0, i, trycnt = 0;
 	struct nfsclds *dsp, *tdsp;
 
 	td = curthread;
@@ -1508,6 +1511,14 @@ nfs_unmount(struct mount *mp, int mntflags)
 	 */
 	if ((mntflags & MNT_FORCE) == 0)
 		nfscl_umount(nmp, td);
+	/* Make sure no nfsiods are assigned to this mount. */
+	mtx_lock(&ncl_iod_mutex);
+	for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
+		if (ncl_iodmount[i] == nmp) {
+			ncl_iodwant[i] = NFSIOD_AVAILABLE;
+			ncl_iodmount[i] = NULL;
+		}
+	mtx_unlock(&ncl_iod_mutex);
 	newnfs_disconnect(&nmp->nm_sockreq);
 	crfree(nmp->nm_sockreq.nr_cred);
 	FREE(nmp->nm_nam, M_SONAME);
diff --git a/sys/nfsclient/nfs_nfsiod.c b/sys/nfsclient/nfs_nfsiod.c
index d34c205..2fb2c88 100644
--- a/sys/nfsclient/nfs_nfsiod.c
+++ b/sys/nfsclient/nfs_nfsiod.c
@@ -308,6 +308,14 @@ nfssvc_iod(void *instance)
 			mtx_unlock(&Giant);
 		mtx_lock(&nfs_iod_mtx);
 		/*
+		 * Make sure the nmp hasn't been dismounted as soon as
+		 * nfs_doio() completes for the last buffer.
+		 */
+		nmp = nfs_iodmount[myiod];
+		if (nmp == NULL)
+			break;
+
+		/*
 		 * If there are more than one iod on this mount, then defect
 		 * so that the iods can be shared out fairly between the mounts
 		 */
diff --git a/sys/nfsclient/nfs_vfsops.c b/sys/nfsclient/nfs_vfsops.c
index 6f00cf9..7a26aa2 100644
--- a/sys/nfsclient/nfs_vfsops.c
+++ b/sys/nfsclient/nfs_vfsops.c
@@ -1362,7 +1362,7 @@ static int
 nfs_unmount(struct mount *mp, int mntflags)
 {
 	struct nfsmount *nmp;
-	int error, flags = 0;
+	int error, flags = 0, i;
 
 	if (mntflags & MNT_FORCE)
 		flags |= FORCECLOSE;
@@ -1387,6 +1387,14 @@ nfs_unmount(struct mount *mp, int mntflags)
 	/*
 	 * We are now committed to the unmount.
 	 */
+	/* Make sure no nfsiods are assigned to this mount. */
+	mtx_lock(&nfs_iod_mtx);
+	for (i = 0; i < NFS_MAXASYNCDAEMON; i++)
+		if (nfs_iodmount[i] == nmp) {
+			nfs_iodwant[i] = NFSIOD_AVAILABLE;
+			nfs_iodmount[i] = NULL;
+		}
+	mtx_unlock(&nfs_iod_mtx);
 	nfs_disconnect(nmp);
 	free(nmp->nm_nam, M_SONAME);