From e83fdf8bb391579fa422d34663cd8c1f82a00dc0 Mon Sep 17 00:00:00 2001
From: Chuck Tuffli <chuck@FreeBSD.org>
Date: Fri, 8 Jan 2021 14:36:37 -0800
Subject: [PATCH] fix big-endian platforms after 6733401935f8

The NVMe byte-swap routines for big-endian platforms used memcpy() to
move the unaligned 64-bit value into a temp register to byte swap it.
Instead of introducing a dependency, manually byte-swap the values in
place.

Point hat:	me
---
 sys/dev/nvme/nvme.h | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/sys/dev/nvme/nvme.h b/sys/dev/nvme/nvme.h
index 67d02ba73fd8..b28a8d4348db 100644
--- a/sys/dev/nvme/nvme.h
+++ b/sys/dev/nvme/nvme.h
@@ -2042,16 +2042,20 @@ static inline void
 nvme_device_self_test_swapbytes(struct nvme_device_self_test_page *s __unused)
 {
 #if _BYTE_ORDER != _LITTLE_ENDIAN
-	uint64_t failing_lba;
-	uint32_t r;
+	uint8_t *tmp;
+	uint32_t r, i;
+	uint8_t b;
 
 	for (r = 0; r < 20; r++) {
 		s->result[r].poh = le64toh(s->result[r].poh);
 		s->result[r].nsid = le32toh(s->result[r].nsid);
 		/* Unaligned 64-bit loads fail on some architectures */
-		memcpy(&failing_lba, s->result[r].failing_lba, sizeof(failing_lba));
-		failing_lba = le64toh(failing_lba);
-		memcpy(s->result[r].failing_lba, &failing_lba, sizeof(failing_lba));
+		tmp = s->result[r].failing_lba;
+		for (i = 0; i < 4; i++) {
+			b = tmp[i];
+			tmp[i] = tmp[7-i];
+			tmp[7-i] = b;
+		}
 	}
 #endif
 }