Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c
index 006f373..9268c12 100644
--- a/arch/x86/mm/mem_encrypt.c
+++ b/arch/x86/mm/mem_encrypt.c
@@ -1,13 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-only
 /*
  * AMD Memory Encryption Support
  *
  * Copyright (C) 2016 Advanced Micro Devices, Inc.
  *
  * Author: Tom Lendacky <thomas.lendacky@amd.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #define DISABLE_BRANCH_PROFILING
@@ -18,6 +15,10 @@
 #include <linux/dma-direct.h>
 #include <linux/swiotlb.h>
 #include <linux/mem_encrypt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/dma-mapping.h>
 
 #include <asm/tlbflush.h>
 #include <asm/fixmap.h>
@@ -44,7 +45,7 @@
 bool sev_enabled __section(.data);
 
 /* Buffer used for early in-place encryption by BSP, no locking needed */
-static char sme_early_buffer[PAGE_SIZE] __aligned(PAGE_SIZE);
+static char sme_early_buffer[PAGE_SIZE] __initdata __aligned(PAGE_SIZE);
 
 /*
  * This routine does not change the underlying encryption setting of the
@@ -301,9 +302,13 @@
 		else
 			split_page_size_mask = 1 << PG_LEVEL_2M;
 
-		kernel_physical_mapping_init(__pa(vaddr & pmask),
-					     __pa((vaddr_end & pmask) + psize),
-					     split_page_size_mask);
+		/*
+		 * kernel_physical_mapping_change() does not flush the TLBs, so
+		 * a TLB flush is required after we exit from the for loop.
+		 */
+		kernel_physical_mapping_change(__pa(vaddr & pmask),
+					       __pa((vaddr_end & pmask) + psize),
+					       split_page_size_mask);
 	}
 
 	ret = 0;
@@ -339,13 +344,37 @@
 {
 	return sme_me_mask && !sev_enabled;
 }
-EXPORT_SYMBOL(sme_active);
 
 bool sev_active(void)
 {
 	return sme_me_mask && sev_enabled;
 }
-EXPORT_SYMBOL(sev_active);
+
+/* Override for DMA direct allocation check - ARCH_HAS_FORCE_DMA_UNENCRYPTED */
+bool force_dma_unencrypted(struct device *dev)
+{
+	/*
+	 * For SEV, all DMA must be to unencrypted addresses.
+	 */
+	if (sev_active())
+		return true;
+
+	/*
+	 * For SME, all DMA must be to unencrypted addresses if the
+	 * device does not support DMA to addresses that include the
+	 * encryption mask.
+	 */
+	if (sme_active()) {
+		u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask));
+		u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask,
+						dev->bus_dma_mask);
+
+		if (dma_dev_mask <= dma_enc_mask)
+			return true;
+	}
+
+	return false;
+}
 
 /* Architecture __weak replacement functions */
 void __init mem_encrypt_free_decrypted_mem(void)
@@ -381,13 +410,6 @@
 	swiotlb_update_mem_attributes();
 
 	/*
-	 * With SEV, DMA operations cannot use encryption, we need to use
-	 * SWIOTLB to bounce buffer DMA operation.
-	 */
-	if (sev_active())
-		dma_ops = &swiotlb_dma_ops;
-
-	/*
 	 * With SEV, we need to unroll the rep string I/O instructions.
 	 */
 	if (sev_active())