Remove the support for using non-mpsafe filesystem modules.

In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.

The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.

Conducted and reviewed by:	attilio
Tested by:	pho

2 files changed, 12 insertions, 29 deletions

diff --git a/sys/security/mac/mac_process.c b/sys/security/mac/mac_process.c
index 214e748..8e5e5bc 100644
--- a/sys/security/mac/mac_process.c
+++ b/sys/security/mac/mac_process.c
@@ -254,7 +254,7 @@ mac_proc_vm_revoke_recurse(struct thread *td, struct ucred *cred,
     struct vm_map *map)
 {
 	vm_map_entry_t vme;
-	int vfslocked, result;
+	int result;
 	vm_prot_t revokeperms;
 	vm_object_t backing_object, object;
 	vm_ooffset_t offset;
@@ -300,7 +300,6 @@ mac_proc_vm_revoke_recurse(struct thread *td, struct ucred *cred,
 		if (object->type != OBJT_VNODE)
 			continue;
 		vp = (struct vnode *)object->handle;
-		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
 		result = vme->max_protection;
 		mac_vnode_check_mmap_downgrade(cred, vp, &result);
@@ -310,10 +309,8 @@ mac_proc_vm_revoke_recurse(struct thread *td, struct ucred *cred,
 		 * but a policy needs to get removed.
 		 */
 		revokeperms = vme->max_protection & ~result;
-		if (!revokeperms) {
-			VFS_UNLOCK_GIANT(vfslocked);
+		if (!revokeperms)
 			continue;
-		}
 		printf("pid %ld: revoking %s perms from %#lx:%ld "
 		    "(max %s/cur %s)\n", (long)td->td_proc->p_pid,
 		    prot2str(revokeperms), (u_long)vme->start,
@@ -369,7 +366,6 @@ mac_proc_vm_revoke_recurse(struct thread *td, struct ucred *cred,
 			    vme->protection & ~revokeperms);
 			vm_map_simplify_entry(map, vme);
 		}
-		VFS_UNLOCK_GIANT(vfslocked);
 	}
 	vm_map_unlock(map);
 }
diff --git a/sys/security/mac/mac_syscalls.c b/sys/security/mac/mac_syscalls.c
index a20938c..ff55ec9 100644
--- a/sys/security/mac/mac_syscalls.c
+++ b/sys/security/mac/mac_syscalls.c
@@ -230,7 +230,7 @@ sys___mac_get_fd(struct thread *td, struct __mac_get_fd_args *uap)
 	struct pipe *pipe;
 	struct socket *so;
 	short label_type;
-	int vfslocked, error;
+	int error;
 
 	error = copyin(uap->mac_p, &mac, sizeof(mac));
 	if (error)
@@ -262,11 +262,9 @@ sys___mac_get_fd(struct thread *td, struct __mac_get_fd_args *uap)
 		}
 		vp = fp->f_vnode;
 		intlabel = mac_vnode_label_alloc();
-		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
 		mac_vnode_copy_label(vp->v_label, intlabel);
 		VOP_UNLOCK(vp, 0);
-		VFS_UNLOCK_GIANT(vfslocked);
 		error = mac_vnode_externalize_label(intlabel, elements,
 		    buffer, mac.m_buflen);
 		mac_vnode_label_free(intlabel);
@@ -322,7 +320,7 @@ sys___mac_get_file(struct thread *td, struct __mac_get_file_args *uap)
 	struct nameidata nd;
 	struct label *intlabel;
 	struct mac mac;
-	int vfslocked, error;
+	int error;
 
 	if (!(mac_labeled & MPC_OBJECT_VNODE))
 		return (EINVAL);
@@ -343,20 +341,18 @@ sys___mac_get_file(struct thread *td, struct __mac_get_file_args *uap)
 	}
 
 	buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
-	NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | FOLLOW, UIO_USERSPACE,
+	NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW, UIO_USERSPACE,
 	    uap->path_p, td);
 	error = namei(&nd);
 	if (error)
 		goto out;
 
 	intlabel = mac_vnode_label_alloc();
-	vfslocked = NDHASGIANT(&nd);
 	mac_vnode_copy_label(nd.ni_vp->v_label, intlabel);
 	error = mac_vnode_externalize_label(intlabel, elements, buffer,
 	    mac.m_buflen);
 
 	NDFREE(&nd, 0);
-	VFS_UNLOCK_GIANT(vfslocked);
 	mac_vnode_label_free(intlabel);
 	if (error == 0)
 		error = copyout(buffer, mac.m_string, strlen(buffer)+1);
@@ -375,7 +371,7 @@ sys___mac_get_link(struct thread *td, struct __mac_get_link_args *uap)
 	struct nameidata nd;
 	struct label *intlabel;
 	struct mac mac;
-	int vfslocked, error;
+	int error;
 
 	if (!(mac_labeled & MPC_OBJECT_VNODE))
 		return (EINVAL);
@@ -396,19 +392,17 @@ sys___mac_get_link(struct thread *td, struct __mac_get_link_args *uap)
 	}
 
 	buffer = malloc(mac.m_buflen, M_MACTEMP, M_WAITOK | M_ZERO);
-	NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | NOFOLLOW, UIO_USERSPACE,
+	NDINIT(&nd, LOOKUP, LOCKLEAF | NOFOLLOW, UIO_USERSPACE,
 	    uap->path_p, td);
 	error = namei(&nd);
 	if (error)
 		goto out;
 
 	intlabel = mac_vnode_label_alloc();
-	vfslocked = NDHASGIANT(&nd);
 	mac_vnode_copy_label(nd.ni_vp->v_label, intlabel);
 	error = mac_vnode_externalize_label(intlabel, elements, buffer,
 	    mac.m_buflen);
 	NDFREE(&nd, 0);
-	VFS_UNLOCK_GIANT(vfslocked);
 	mac_vnode_label_free(intlabel);
 
 	if (error == 0)
@@ -432,7 +426,7 @@ sys___mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
 	struct vnode *vp;
 	struct mac mac;
 	char *buffer;
-	int error, vfslocked;
+	int error;
 
 	error = copyin(uap->mac_p, &mac, sizeof(mac));
 	if (error)
@@ -467,10 +461,8 @@ sys___mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
 			break;
 		}
 		vp = fp->f_vnode;
-		vfslocked = VFS_LOCK_GIANT(vp->v_mount);
 		error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
 		if (error != 0) {
-			VFS_UNLOCK_GIANT(vfslocked);
 			mac_vnode_label_free(intlabel);
 			break;
 		}
@@ -478,7 +470,6 @@ sys___mac_set_fd(struct thread *td, struct __mac_set_fd_args *uap)
 		error = vn_setlabel(vp, intlabel, td->td_ucred);
 		VOP_UNLOCK(vp, 0);
 		vn_finished_write(mp);
-		VFS_UNLOCK_GIANT(vfslocked);
 		mac_vnode_label_free(intlabel);
 		break;
 
@@ -532,7 +523,7 @@ sys___mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
 	struct mount *mp;
 	struct mac mac;
 	char *buffer;
-	int vfslocked, error;
+	int error;
 
 	if (!(mac_labeled & MPC_OBJECT_VNODE))
 		return (EINVAL);
@@ -558,10 +549,9 @@ sys___mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
 	if (error)
 		goto out;
 
-	NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | FOLLOW, UIO_USERSPACE,
+	NDINIT(&nd, LOOKUP, LOCKLEAF | FOLLOW, UIO_USERSPACE,
 	    uap->path_p, td);
 	error = namei(&nd);
-	vfslocked = NDHASGIANT(&nd);
 	if (error == 0) {
 		error = vn_start_write(nd.ni_vp, &mp, V_WAIT | PCATCH);
 		if (error == 0) {
@@ -572,7 +562,6 @@ sys___mac_set_file(struct thread *td, struct __mac_set_file_args *uap)
 	}
 
 	NDFREE(&nd, 0);
-	VFS_UNLOCK_GIANT(vfslocked);
 out:
 	mac_vnode_label_free(intlabel);
 	return (error);
@@ -586,7 +575,7 @@ sys___mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
 	struct mount *mp;
 	struct mac mac;
 	char *buffer;
-	int vfslocked, error;
+	int error;
 
 	if (!(mac_labeled & MPC_OBJECT_VNODE))
 		return (EINVAL);
@@ -612,10 +601,9 @@ sys___mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
 	if (error)
 		goto out;
 
-	NDINIT(&nd, LOOKUP, MPSAFE | LOCKLEAF | NOFOLLOW, UIO_USERSPACE,
+	NDINIT(&nd, LOOKUP, LOCKLEAF | NOFOLLOW, UIO_USERSPACE,
 	    uap->path_p, td);
 	error = namei(&nd);
-	vfslocked = NDHASGIANT(&nd);
 	if (error == 0) {
 		error = vn_start_write(nd.ni_vp, &mp, V_WAIT | PCATCH);
 		if (error == 0) {
@@ -626,7 +614,6 @@ sys___mac_set_link(struct thread *td, struct __mac_set_link_args *uap)
 	}
 
 	NDFREE(&nd, 0);
-	VFS_UNLOCK_GIANT(vfslocked);
 out:
 	mac_vnode_label_free(intlabel);
 	return (error);