From e39cc26762ef235db9d4f3a54412ad69a1934bd1 Mon Sep 17 00:00:00 2001
From: Warner Losh <imp@FreeBSD.org>
Date: Wed, 18 Jul 2018 22:45:26 +0000
Subject: [PATCH] If rootdev is set, use it as currdev.

Setting rootdev in the enviornment should specify things
completely. If it is set, then have it override everything else.

PR: 229770
Differential Review: https://reviews.freebsd.org/D16322
---
 stand/efi/loader/main.c | 23 ++++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/stand/efi/loader/main.c b/stand/efi/loader/main.c
index ff1ee82edecc..88b020191797 100644
--- a/stand/efi/loader/main.c
+++ b/stand/efi/loader/main.c
@@ -165,17 +165,22 @@ has_keyboard(void)
 	return retval;
 }
 
+static void
+set_currdev(const char *devname)
+{
+
+	env_setenv("currdev", EV_VOLATILE, devname, efi_setcurrdev, env_nounset);
+	env_setenv("loaddev", EV_VOLATILE, devname, env_noset, env_nounset);
+}
+
 static void
 set_currdev_devdesc(struct devdesc *currdev)
 {
 	const char *devname;
 
 	devname = efi_fmtdev(currdev);
-
 	printf("Setting currdev to %s\n", devname);
-
-	env_setenv("currdev", EV_VOLATILE, devname, efi_setcurrdev, env_nounset);
-	env_setenv("loaddev", EV_VOLATILE, devname, env_noset, env_nounset);
+	set_currdev(devname);
 }
 
 static void
@@ -279,6 +284,14 @@ find_currdev(EFI_LOADED_IMAGE *img)
 	struct devsw *dev;
 	int unit;
 	uint64_t extra;
+	char *rootdev;
+
+	rootdev = getenv("rootdev");
+	if (rootdev != NULL) {
+		printf("Setting currdev to configured rootdev %s\n", rootdev);
+		set_currdev(rootdev);
+		return (0);
+	}
 
 #ifdef EFI_ZFS_BOOT
 	/*
@@ -616,7 +629,7 @@ main(int argc, CHAR16 *argv[])
 	 * set the env based on it.
 	 */
 	boot_howto_to_env(howto);
-	
+
 	if (efi_copy_init()) {
 		printf("failed to allocate staging area\n");
 		return (EFI_BUFFER_TOO_SMALL);