Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/arm/xen/Makefile b/arch/arm/xen/Makefile
index 2279521..c32d047 100644
--- a/arch/arm/xen/Makefile
+++ b/arch/arm/xen/Makefile
@@ -1,2 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
 obj-y		:= enlighten.o hypercall.o grant-table.o p2m.o mm.o
-obj-$(CONFIG_XEN_EFI) += efi.o
diff --git a/arch/arm/xen/efi.c b/arch/arm/xen/efi.c
deleted file mode 100644
index b4d7895..0000000
--- a/arch/arm/xen/efi.c
+++ /dev/null
@@ -1,40 +0,0 @@
-/*
- * Copyright (c) 2015, Linaro Limited, Shannon Zhao
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <linux/efi.h>
-#include <xen/xen-ops.h>
-#include <asm/xen/xen-ops.h>
-
-/* Set XEN EFI runtime services function pointers. Other fields of struct efi,
- * e.g. efi.systab, will be set like normal EFI.
- */
-void __init xen_efi_runtime_setup(void)
-{
-	efi.get_time                 = xen_efi_get_time;
-	efi.set_time                 = xen_efi_set_time;
-	efi.get_wakeup_time          = xen_efi_get_wakeup_time;
-	efi.set_wakeup_time          = xen_efi_set_wakeup_time;
-	efi.get_variable             = xen_efi_get_variable;
-	efi.get_next_variable        = xen_efi_get_next_variable;
-	efi.set_variable             = xen_efi_set_variable;
-	efi.query_variable_info      = xen_efi_query_variable_info;
-	efi.update_capsule           = xen_efi_update_capsule;
-	efi.query_capsule_caps       = xen_efi_query_capsule_caps;
-	efi.get_next_high_mono_count = xen_efi_get_next_high_mono_count;
-	efi.reset_system             = xen_efi_reset_system;
-}
-EXPORT_SYMBOL_GPL(xen_efi_runtime_setup);
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
index 07060e5..dd6804a 100644
--- a/arch/arm/xen/enlighten.c
+++ b/arch/arm/xen/enlighten.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-only
 #include <xen/xen.h>
 #include <xen/events.h>
 #include <xen/grant_table.h>
@@ -14,7 +15,6 @@
 #include <xen/xen-ops.h>
 #include <asm/xen/hypervisor.h>
 #include <asm/xen/hypercall.h>
-#include <asm/xen/xen-ops.h>
 #include <asm/system_misc.h>
 #include <asm/efi.h>
 #include <linux/interrupt.h>
@@ -62,29 +62,6 @@
 uint32_t xen_start_flags;
 EXPORT_SYMBOL(xen_start_flags);
 
-int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
-			       unsigned long addr,
-			       xen_pfn_t *gfn, int nr,
-			       int *err_ptr, pgprot_t prot,
-			       unsigned domid,
-			       struct page **pages)
-{
-	return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr,
-					 prot, domid, pages);
-}
-EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
-
-/* Not used by XENFEAT_auto_translated guests. */
-int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
-                              unsigned long addr,
-                              xen_pfn_t gfn, int nr,
-                              pgprot_t prot, unsigned domid,
-                              struct page **pages)
-{
-	return -ENOSYS;
-}
-EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
-
 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
 			       int nr, struct page **pages)
 {
@@ -92,17 +69,6 @@
 }
 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
 
-/* Not used by XENFEAT_auto_translated guests. */
-int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
-			       unsigned long addr,
-			       xen_pfn_t *mfn, int nr,
-			       int *err_ptr, pgprot_t prot,
-			       unsigned int domid, struct page **pages)
-{
-	return -ENOSYS;
-}
-EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
-
 static void xen_read_wallclock(struct timespec64 *ts)
 {
 	u32 version;
@@ -470,7 +436,7 @@
 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
-EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op_raw);
 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
 EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist);
 EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op);
diff --git a/arch/arm/xen/hypercall.S b/arch/arm/xen/hypercall.S
index b0b80c0..b11bba5 100644
--- a/arch/arm/xen/hypercall.S
+++ b/arch/arm/xen/hypercall.S
@@ -113,8 +113,7 @@
 
 	/*
 	 * Disable userspace access from kernel. This is fine to do it
-	 * unconditionally as no set_fs(KERNEL_DS)/set_fs(get_ds()) is
-	 * called before.
+	 * unconditionally as no set_fs(KERNEL_DS) is called before.
 	 */
 	uaccess_disable r4
 
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
index 785d2a5..38fa917 100644
--- a/arch/arm/xen/mm.c
+++ b/arch/arm/xen/mm.c
@@ -1,6 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0-only
 #include <linux/cpu.h>
-#include <linux/dma-mapping.h>
-#include <linux/bootmem.h>
+#include <linux/dma-noncoherent.h>
 #include <linux/gfp.h>
 #include <linux/highmem.h>
 #include <linux/export.h>
@@ -8,7 +8,6 @@
 #include <linux/of_address.h>
 #include <linux/slab.h>
 #include <linux/types.h>
-#include <linux/dma-mapping.h>
 #include <linux/vmalloc.h>
 #include <linux/swiotlb.h>
 
@@ -29,112 +28,66 @@
 
 	for_each_memblock(memory, reg) {
 		if (reg->base < (phys_addr_t)0xffffffff) {
-			flags |= __GFP_DMA;
+			if (IS_ENABLED(CONFIG_ZONE_DMA32))
+				flags |= __GFP_DMA32;
+			else
+				flags |= __GFP_DMA;
 			break;
 		}
 	}
 	return __get_free_pages(flags, order);
 }
 
-enum dma_cache_op {
-       DMA_UNMAP,
-       DMA_MAP,
-};
 static bool hypercall_cflush = false;
 
-/* functions called by SWIOTLB */
-
-static void dma_cache_maint(dma_addr_t handle, unsigned long offset,
-	size_t size, enum dma_data_direction dir, enum dma_cache_op op)
+/* buffers in highmem or foreign pages cannot cross page boundaries */
+static void dma_cache_maint(dma_addr_t handle, size_t size, u32 op)
 {
 	struct gnttab_cache_flush cflush;
-	unsigned long xen_pfn;
-	size_t left = size;
 
-	xen_pfn = (handle >> XEN_PAGE_SHIFT) + offset / XEN_PAGE_SIZE;
-	offset %= XEN_PAGE_SIZE;
+	cflush.a.dev_bus_addr = handle & XEN_PAGE_MASK;
+	cflush.offset = xen_offset_in_page(handle);
+	cflush.op = op;
 
 	do {
-		size_t len = left;
-	
-		/* buffers in highmem or foreign pages cannot cross page
-		 * boundaries */
-		if (len + offset > XEN_PAGE_SIZE)
-			len = XEN_PAGE_SIZE - offset;
+		if (size + cflush.offset > XEN_PAGE_SIZE)
+			cflush.length = XEN_PAGE_SIZE - cflush.offset;
+		else
+			cflush.length = size;
 
-		cflush.op = 0;
-		cflush.a.dev_bus_addr = xen_pfn << XEN_PAGE_SHIFT;
-		cflush.offset = offset;
-		cflush.length = len;
+		HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1);
 
-		if (op == DMA_UNMAP && dir != DMA_TO_DEVICE)
-			cflush.op = GNTTAB_CACHE_INVAL;
-		if (op == DMA_MAP) {
-			if (dir == DMA_FROM_DEVICE)
-				cflush.op = GNTTAB_CACHE_INVAL;
-			else
-				cflush.op = GNTTAB_CACHE_CLEAN;
-		}
-		if (cflush.op)
-			HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1);
-
-		offset = 0;
-		xen_pfn++;
-		left -= len;
-	} while (left);
+		cflush.offset = 0;
+		cflush.a.dev_bus_addr += cflush.length;
+		size -= cflush.length;
+	} while (size);
 }
 
-static void __xen_dma_page_dev_to_cpu(struct device *hwdev, dma_addr_t handle,
-		size_t size, enum dma_data_direction dir)
+/*
+ * Dom0 is mapped 1:1, and while the Linux page can span across multiple Xen
+ * pages, it is not possible for it to contain a mix of local and foreign Xen
+ * pages.  Calling pfn_valid on a foreign mfn will always return false, so if
+ * pfn_valid returns true the pages is local and we can use the native
+ * dma-direct functions, otherwise we call the Xen specific version.
+ */
+void xen_dma_sync_for_cpu(struct device *dev, dma_addr_t handle,
+		phys_addr_t paddr, size_t size, enum dma_data_direction dir)
 {
-	dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_UNMAP);
+	if (pfn_valid(PFN_DOWN(handle)))
+		arch_sync_dma_for_cpu(dev, paddr, size, dir);
+	else if (dir != DMA_TO_DEVICE)
+		dma_cache_maint(handle, size, GNTTAB_CACHE_INVAL);
 }
 
-static void __xen_dma_page_cpu_to_dev(struct device *hwdev, dma_addr_t handle,
-		size_t size, enum dma_data_direction dir)
+void xen_dma_sync_for_device(struct device *dev, dma_addr_t handle,
+		phys_addr_t paddr, size_t size, enum dma_data_direction dir)
 {
-	dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_MAP);
-}
-
-void __xen_dma_map_page(struct device *hwdev, struct page *page,
-	     dma_addr_t dev_addr, unsigned long offset, size_t size,
-	     enum dma_data_direction dir, unsigned long attrs)
-{
-	if (is_device_dma_coherent(hwdev))
-		return;
-	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
-		return;
-
-	__xen_dma_page_cpu_to_dev(hwdev, dev_addr, size, dir);
-}
-
-void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
-		size_t size, enum dma_data_direction dir,
-		unsigned long attrs)
-
-{
-	if (is_device_dma_coherent(hwdev))
-		return;
-	if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
-		return;
-
-	__xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
-}
-
-void __xen_dma_sync_single_for_cpu(struct device *hwdev,
-		dma_addr_t handle, size_t size, enum dma_data_direction dir)
-{
-	if (is_device_dma_coherent(hwdev))
-		return;
-	__xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
-}
-
-void __xen_dma_sync_single_for_device(struct device *hwdev,
-		dma_addr_t handle, size_t size, enum dma_data_direction dir)
-{
-	if (is_device_dma_coherent(hwdev))
-		return;
-	__xen_dma_page_cpu_to_dev(hwdev, handle, size, dir);
+	if (pfn_valid(PFN_DOWN(handle)))
+		arch_sync_dma_for_device(dev, paddr, size, dir);
+	else if (dir == DMA_FROM_DEVICE)
+		dma_cache_maint(handle, size, GNTTAB_CACHE_INVAL);
+	else
+		dma_cache_maint(handle, size, GNTTAB_CACHE_CLEAN);
 }
 
 bool xen_arch_need_swiotlb(struct device *dev,
@@ -160,7 +113,7 @@
 	 * memory and we are not able to flush the cache.
 	 */
 	return (!hypercall_cflush && (xen_pfn != bfn) &&
-		!is_device_dma_coherent(dev));
+		!dev_is_dma_coherent(dev));
 }
 
 int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,
@@ -174,16 +127,11 @@
 	*dma_handle = pstart;
 	return 0;
 }
-EXPORT_SYMBOL_GPL(xen_create_contiguous_region);
 
 void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order)
 {
 	return;
 }
-EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region);
-
-const struct dma_map_ops *xen_dma_ops;
-EXPORT_SYMBOL(xen_dma_ops);
 
 int __init xen_mm_init(void)
 {
@@ -191,7 +139,6 @@
 	if (!xen_initial_domain())
 		return 0;
 	xen_swiotlb_init(1, false);
-	xen_dma_ops = &xen_swiotlb_dma_ops;
 
 	cflush.op = 0;
 	cflush.a.dev_bus_addr = 0;
diff --git a/arch/arm/xen/p2m.c b/arch/arm/xen/p2m.c
index 0641ba5..e52950a 100644
--- a/arch/arm/xen/p2m.c
+++ b/arch/arm/xen/p2m.c
@@ -1,4 +1,5 @@
-#include <linux/bootmem.h>
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/memblock.h>
 #include <linux/gfp.h>
 #include <linux/export.h>
 #include <linux/spinlock.h>
@@ -70,8 +71,9 @@
 		entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
 		if (entry->pfn <= pfn &&
 				entry->pfn + entry->nr_pages > pfn) {
+			unsigned long mfn = entry->mfn + (pfn - entry->pfn);
 			read_unlock_irqrestore(&p2m_lock, irqflags);
-			return entry->mfn + (pfn - entry->pfn);
+			return mfn;
 		}
 		if (pfn < entry->pfn)
 			n = n->rb_left;
@@ -156,6 +158,7 @@
 	rc = xen_add_phys_to_mach_entry(p2m_entry);
 	if (rc < 0) {
 		write_unlock_irqrestore(&p2m_lock, irqflags);
+		kfree(p2m_entry);
 		return false;
 	}
 	write_unlock_irqrestore(&p2m_lock, irqflags);