diff --git a/sys/fs/nullfs/null_subr.c b/sys/fs/nullfs/null_subr.c
--- a/sys/fs/nullfs/null_subr.c
+++ b/sys/fs/nullfs/null_subr.c
@@ -263,16 +263,14 @@
 	 * some time after construction, which is typical case.
 	 * null_open rechecks.
 	 */
-	if ((lowervp->v_irflag & VIRF_PGREAD) != 0) {
+	if ((vn_irflag_read(lowervp) & VIRF_PGREAD) != 0) {
 		MPASS(lowervp->v_object != NULL);
-		if ((vp->v_irflag & VIRF_PGREAD) == 0) {
+		if ((vn_irflag_read(vp) & VIRF_PGREAD) == 0) {
 			if (vp->v_object == NULL)
 				vp->v_object = lowervp->v_object;
 			else
 				MPASS(vp->v_object == lowervp->v_object);
-			VI_LOCK(vp);
-			vp->v_irflag |= VIRF_PGREAD;
-			VI_UNLOCK(vp);
+			vn_irflag_set_cond(vp, VIRF_PGREAD);
 		} else {
 			MPASS(vp->v_object != NULL);
 		}
diff --git a/sys/fs/nullfs/null_vnops.c b/sys/fs/nullfs/null_vnops.c
--- a/sys/fs/nullfs/null_vnops.c
+++ b/sys/fs/nullfs/null_vnops.c
@@ -458,12 +458,10 @@
 	retval = null_bypass(&ap->a_gen);
 	if (retval == 0) {
 		vp->v_object = ldvp->v_object;
-		if ((ldvp->v_irflag & VIRF_PGREAD) != 0) {
+		if ((vn_irflag_read(ldvp) & VIRF_PGREAD) != 0) {
 			MPASS(vp->v_object != NULL);
-			if ((vp->v_irflag & VIRF_PGREAD) == 0) {
-				VI_LOCK(vp);
-				vp->v_irflag |= VIRF_PGREAD;
-				VI_UNLOCK(vp);
+			if ((vn_irflag_read(vp) & VIRF_PGREAD) == 0) {
+				vn_irflag_set_cond(vp, VIRF_PGREAD);
 			}
 		}
 	}
diff --git a/sys/fs/tmpfs/tmpfs_subr.c b/sys/fs/tmpfs/tmpfs_subr.c
--- a/sys/fs/tmpfs/tmpfs_subr.c
+++ b/sys/fs/tmpfs/tmpfs_subr.c
@@ -698,7 +698,7 @@
 		vp->v_object = object;
 		object->un_pager.swp.swp_tmpfs = vp;
 		vm_object_set_flag(object, OBJ_TMPFS);
-		vp->v_irflag |= VIRF_PGREAD;
+		vn_irflag_set_locked(vp, VIRF_PGREAD);
 		VI_UNLOCK(vp);
 		VM_OBJECT_WUNLOCK(object);
 		break;
diff --git a/sys/fs/tmpfs/tmpfs_vnops.c b/sys/fs/tmpfs/tmpfs_vnops.c
--- a/sys/fs/tmpfs/tmpfs_vnops.c
+++ b/sys/fs/tmpfs/tmpfs_vnops.c
@@ -600,7 +600,7 @@
 	int error;
 
 	vp = v->a_vp;
-	VNPASS((vp->v_irflag & VIRF_PGREAD) != 0, vp);
+	VNPASS((vn_irflag_read(vp) & VIRF_PGREAD) != 0, vp);
 
 	if (v->a_uio->uio_offset < 0)
 		return (EINVAL);
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -1717,6 +1717,7 @@
 	KASSERT(vp->v_pollinfo == NULL, ("stale v_pollinfo %p", vp));
 	vp->v_type = VNON;
 	vp->v_op = vops;
+	vp->v_irflag = 0;
 	v_init_counters(vp);
 	vp->v_bufobj.bo_ops = &buf_ops_bio;
 #ifdef DIAGNOSTIC
@@ -1821,7 +1822,6 @@
 	vp->v_rdev = NULL;
 	vp->v_fifoinfo = NULL;
 	vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0;
-	vp->v_irflag = 0;
 	vp->v_iflag = 0;
 	vp->v_vflag = 0;
 	bo->bo_flag = 0;
@@ -3868,14 +3868,14 @@
 	/*
 	 * Don't vgonel if we're already doomed.
 	 */
-	if (vp->v_irflag & VIRF_DOOMED)
+	if (VN_IS_DOOMED(vp))
 		return;
 	/*
 	 * Paired with freevnode.
 	 */
 	vn_seqc_write_begin_locked(vp);
 	vunlazy_gone(vp);
-	vp->v_irflag |= VIRF_DOOMED;
+	vn_irflag_set_locked(vp, VIRF_DOOMED);
 
 	/*
 	 * Check to see if the vnode is in use.  If so, we have to
@@ -4001,6 +4001,7 @@
 	char buf[256], buf2[16];
 	u_long flags;
 	u_int holdcnt;
+	short irflag;
 
 	va_start(ap, fmt);
 	vprintf(fmt, ap);
@@ -4036,11 +4037,12 @@
 
 	buf[0] = '\0';
 	buf[1] = '\0';
-	if (vp->v_irflag & VIRF_DOOMED)
+	irflag = vn_irflag_read(vp);
+	if (irflag & VIRF_DOOMED)
 		strlcat(buf, "|VIRF_DOOMED", sizeof(buf));
-	if (vp->v_irflag & VIRF_PGREAD)
+	if (irflag & VIRF_PGREAD)
 		strlcat(buf, "|VIRF_PGREAD", sizeof(buf));
-	flags = vp->v_irflag & ~(VIRF_DOOMED | VIRF_PGREAD);
+	flags = irflag & ~(VIRF_DOOMED | VIRF_PGREAD);
 	if (flags != 0) {
 		snprintf(buf2, sizeof(buf2), "|VIRF(0x%lx)", flags);
 		strlcat(buf, buf2, sizeof(buf));
@@ -6794,3 +6796,66 @@
 	vn_seqc_write_end_locked(vp);
 	VI_UNLOCK(vp);
 }
+
+void
+vn_irflag_set_locked(struct vnode *vp, short toset)
+{
+	short flags;
+
+	ASSERT_VI_LOCKED(vp, __func__);
+	flags = vn_irflag_read(vp);
+	VNASSERT((flags & toset) == 0, vp,
+	    ("%s: some of the passed flags already set (have %d, passed %d)\n",
+	    __func__, flags, toset));
+	atomic_store_short(&vp->v_irflag, flags | toset);
+}
+
+void
+vn_irflag_set(struct vnode *vp, short toset)
+{
+
+	VI_LOCK(vp);
+	vn_irflag_set_locked(vp, toset);
+	VI_UNLOCK(vp);
+}
+
+void
+vn_irflag_set_cond_locked(struct vnode *vp, short toset)
+{
+	short flags;
+
+	ASSERT_VI_LOCKED(vp, __func__);
+	flags = vn_irflag_read(vp);
+	atomic_store_short(&vp->v_irflag, flags | toset);
+}
+
+void
+vn_irflag_set_cond(struct vnode *vp, short toset)
+{
+
+	VI_LOCK(vp);
+	vn_irflag_set_cond_locked(vp, toset);
+	VI_UNLOCK(vp);
+}
+
+void
+vn_irflag_unset_locked(struct vnode *vp, short tounset)
+{
+	short flags;
+
+	ASSERT_VI_LOCKED(vp, __func__);
+	flags = vn_irflag_read(vp);
+	VNASSERT((flags & tounset) == tounset, vp,
+	    ("%s: some of the passed flags not set (have %d, passed %d)\n",
+	    __func__, flags, tounset));
+	atomic_store_short(&vp->v_irflag, flags & ~tounset);
+}
+
+void
+vn_irflag_unset(struct vnode *vp, short tounset)
+{
+
+	VI_LOCK(vp);
+	vn_irflag_unset_locked(vp, tounset);
+	VI_UNLOCK(vp);
+}
diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -991,7 +991,7 @@
 	 * allows us to avoid unneeded work outright.
 	 */
 	if (vn_io_pgcache_read_enable && !mac_vnode_check_read_enabled() &&
-	    (vp->v_irflag & (VIRF_DOOMED | VIRF_PGREAD)) == VIRF_PGREAD) {
+	    (vn_irflag_read(vp) & (VIRF_DOOMED | VIRF_PGREAD)) == VIRF_PGREAD) {
 		error = VOP_READ_PGCACHE(vp, uio, ioflag, fp->f_cred);
 		if (error == 0) {
 			fp->f_nextoff[UIO_READ] = uio->uio_offset;
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -797,6 +797,14 @@
 #define	vn_rangelock_trywlock(vp, start, end)				\
 	rangelock_trywlock(&(vp)->v_rl, (start), (end), VI_MTX(vp))
 
+#define	vn_irflag_read(vp)	atomic_load_short(&(vp)->v_irflag)
+void	vn_irflag_set_locked(struct vnode *vp, short toset);
+void	vn_irflag_set(struct vnode *vp, short toset);
+void	vn_irflag_set_cond_locked(struct vnode *vp, short toset);
+void	vn_irflag_set_cond(struct vnode *vp, short toset);
+void	vn_irflag_unset_locked(struct vnode *vp, short tounset);
+void	vn_irflag_unset(struct vnode *vp, short tounset);
+
 int	vfs_cache_lookup(struct vop_lookup_args *ap);
 int	vfs_cache_root(struct mount *mp, int flags, struct vnode **vpp);
 void	vfs_timestamp(struct timespec *);
@@ -979,7 +987,7 @@
 #define	VOP_UNSET_TEXT_CHECKED(vp)		VOP_UNSET_TEXT((vp))
 #endif
 
-#define	VN_IS_DOOMED(vp)	__predict_false((vp)->v_irflag & VIRF_DOOMED)
+#define	VN_IS_DOOMED(vp)	__predict_false((vn_irflag_read(vp) & VIRF_DOOMED) != 0)
 
 void	vput(struct vnode *vp);
 void	vrele(struct vnode *vp);
diff --git a/sys/ufs/ufs/ufs_vnops.c b/sys/ufs/ufs/ufs_vnops.c
--- a/sys/ufs/ufs/ufs_vnops.c
+++ b/sys/ufs/ufs/ufs_vnops.c
@@ -283,10 +283,8 @@
 
 	ip = VTOI(vp);
 	vnode_create_vobject(vp, DIP(ip, i_size), ap->a_td);
-	if (vp->v_type == VREG && (vp->v_irflag & VIRF_PGREAD) == 0) {
-		VI_LOCK(vp);
-		vp->v_irflag |= VIRF_PGREAD;
-		VI_UNLOCK(vp);
+	if (vp->v_type == VREG && (vn_irflag_read(vp) & VIRF_PGREAD) == 0) {
+		vn_irflag_set_cond(vp, VIRF_PGREAD);
 	}
 
 	/*
@@ -2947,7 +2945,7 @@
 
 	uio = ap->a_uio;
 	vp = ap->a_vp;
-	VNPASS((vp->v_irflag & VIRF_PGREAD) != 0, vp);
+	VNPASS((vn_irflag_read(vp) & VIRF_PGREAD) != 0, vp);
 
 	if (uio->uio_resid > ptoa(io_hold_cnt) || uio->uio_offset < 0 ||
 	    (ap->a_ioflag & IO_DIRECT) != 0)