From e3389acee7d3010305c5d1da99e77aa8570d99ad Mon Sep 17 00:00:00 2001
From: riastradh <riastradh@NetBSD.org>
Date: Wed, 17 Feb 2016 01:42:25 +0000
Subject: [PATCH] Make hyperentropy rndsource work synchronously, again.

This time for real!  *crosses fingers*
---
 sys/rump/librump/rumpkern/hyperentropy.c | 49 ++++--------------------
 1 file changed, 8 insertions(+), 41 deletions(-)

diff --git a/sys/rump/librump/rumpkern/hyperentropy.c b/sys/rump/librump/rumpkern/hyperentropy.c
index d1b9a5f6beb7..c7b4a48e314f 100644
--- a/sys/rump/librump/rumpkern/hyperentropy.c
+++ b/sys/rump/librump/rumpkern/hyperentropy.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: hyperentropy.c,v 1.11 2016/01/26 23:12:17 pooka Exp $	*/
+/*	$NetBSD: hyperentropy.c,v 1.12 2016/02/17 01:42:25 riastradh Exp $	*/
 
 /*
  * Copyright (c) 2014 Antti Kantee.  All Rights Reserved.
@@ -26,10 +26,9 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: hyperentropy.c,v 1.11 2016/01/26 23:12:17 pooka Exp $");
+__KERNEL_RCSID(0, "$NetBSD: hyperentropy.c,v 1.12 2016/02/17 01:42:25 riastradh Exp $");
 
 #include <sys/param.h>
-#include <sys/atomic.h>
 #include <sys/kmem.h>
 #include <sys/rndpool.h>
 #include <sys/rndsource.h>
@@ -39,12 +38,10 @@ __KERNEL_RCSID(0, "$NetBSD: hyperentropy.c,v 1.11 2016/01/26 23:12:17 pooka Exp
 #include <rump/rumpuser.h>
 
 static krndsource_t rndsrc;
-static volatile unsigned hyperentropy_wanted;
-static void *feedrandom_softint;
 
 #define MAXGET (RND_POOLBITS/NBBY)
 static void
-feedrandom(size_t bytes)
+feedrandom(size_t bytes, void *cookie __unused)
 {
 	uint8_t *rnddata;
 	size_t dsize;
@@ -52,46 +49,16 @@ feedrandom(size_t bytes)
 	rnddata = kmem_intr_alloc(MAXGET, KM_SLEEP);
 	if (rumpuser_getrandom(rnddata, MIN(MAXGET, bytes),
 	    RUMPUSER_RANDOM_HARD|RUMPUSER_RANDOM_NOWAIT, &dsize) == 0)
-		rnd_add_data(&rndsrc, rnddata, dsize, NBBY*dsize);
+		rnd_add_data_sync(&rndsrc, rnddata, dsize, NBBY*dsize);
 	kmem_intr_free(rnddata, MAXGET);
 }
 
-static void
-feedrandom_intr(void *cookie __unused)
-{
-
-	feedrandom(atomic_swap_uint(&hyperentropy_wanted, 0));
-}
-
-static void
-feedrandom_cb(size_t bytes, void *cookie __unused)
-{
-	unsigned old, new;
-
-	do {
-		old = hyperentropy_wanted;
-		new = ((MAXGET - old) < bytes? MAXGET : (old + bytes));
-	} while (atomic_cas_uint(&hyperentropy_wanted, old, new) != old);
-
-	softint_schedule(feedrandom_softint);
-}
-
 void
 rump_hyperentropy_init(void)
 {
 
-	if (rump_threads) {
-		feedrandom_softint =
-		    softint_establish(SOFTINT_CLOCK|SOFTINT_MPSAFE,
-			feedrandom_intr, NULL);
-		KASSERT(feedrandom_softint != NULL);
-		rndsource_setcb(&rndsrc, feedrandom_cb, &rndsrc);
-		rnd_attach_source(&rndsrc, "rump_hyperent", RND_TYPE_VM,
-		    RND_FLAG_COLLECT_VALUE|RND_FLAG_HASCB);
-	} else {
-		/* without threads, just fill the pool */
-		rnd_attach_source(&rndsrc, "rump_hyperent", RND_TYPE_VM,
-		    RND_FLAG_COLLECT_VALUE);
-		feedrandom(MAXGET);
-	}
+	rndsource_setcb(&rndsrc, &feedrandom, NULL);
+	rnd_attach_source(&rndsrc, "rump_hyperent", RND_TYPE_VM,
+	    RND_FLAG_COLLECT_VALUE|RND_FLAG_HASCB);
+	feedrandom(MAXGET, NULL);
 }