v4.19.13 snapshot.
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
new file mode 100644
index 0000000..1907db2
--- /dev/null
+++ b/drivers/firmware/efi/memmap.c
@@ -0,0 +1,345 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Common EFI memory map functions.
+ */
+
+#define pr_fmt(fmt) "efi: " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/efi.h>
+#include <linux/io.h>
+#include <asm/early_ioremap.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+
+static phys_addr_t __init __efi_memmap_alloc_early(unsigned long size)
+{
+ return memblock_alloc(size, 0);
+}
+
+static phys_addr_t __init __efi_memmap_alloc_late(unsigned long size)
+{
+ unsigned int order = get_order(size);
+ struct page *p = alloc_pages(GFP_KERNEL, order);
+
+ if (!p)
+ return 0;
+
+ return PFN_PHYS(page_to_pfn(p));
+}
+
+/**
+ * efi_memmap_alloc - Allocate memory for the EFI memory map
+ * @num_entries: Number of entries in the allocated map.
+ *
+ * Depending on whether mm_init() has already been invoked or not,
+ * either memblock or "normal" page allocation is used.
+ *
+ * Returns the physical address of the allocated memory map on
+ * success, zero on failure.
+ */
+phys_addr_t __init efi_memmap_alloc(unsigned int num_entries)
+{
+ unsigned long size = num_entries * efi.memmap.desc_size;
+
+ if (slab_is_available())
+ return __efi_memmap_alloc_late(size);
+
+ return __efi_memmap_alloc_early(size);
+}
+
+/**
+ * __efi_memmap_init - Common code for mapping the EFI memory map
+ * @data: EFI memory map data
+ * @late: Use early or late mapping function?
+ *
+ * This function takes care of figuring out which function to use to
+ * map the EFI memory map in efi.memmap based on how far into the boot
+ * we are.
+ *
+ * During bootup @late should be %false since we only have access to
+ * the early_memremap*() functions as the vmalloc space isn't setup.
+ * Once the kernel is fully booted we can fallback to the more robust
+ * memremap*() API.
+ *
+ * Returns zero on success, a negative error code on failure.
+ */
+static int __init
+__efi_memmap_init(struct efi_memory_map_data *data, bool late)
+{
+ struct efi_memory_map map;
+ phys_addr_t phys_map;
+
+ if (efi_enabled(EFI_PARAVIRT))
+ return 0;
+
+ phys_map = data->phys_map;
+
+ if (late)
+ map.map = memremap(phys_map, data->size, MEMREMAP_WB);
+ else
+ map.map = early_memremap(phys_map, data->size);
+
+ if (!map.map) {
+ pr_err("Could not map the memory map!\n");
+ return -ENOMEM;
+ }
+
+ map.phys_map = data->phys_map;
+ map.nr_map = data->size / data->desc_size;
+ map.map_end = map.map + data->size;
+
+ map.desc_version = data->desc_version;
+ map.desc_size = data->desc_size;
+ map.late = late;
+
+ set_bit(EFI_MEMMAP, &efi.flags);
+
+ efi.memmap = map;
+
+ return 0;
+}
+
+/**
+ * efi_memmap_init_early - Map the EFI memory map data structure
+ * @data: EFI memory map data
+ *
+ * Use early_memremap() to map the passed in EFI memory map and assign
+ * it to efi.memmap.
+ */
+int __init efi_memmap_init_early(struct efi_memory_map_data *data)
+{
+ /* Cannot go backwards */
+ WARN_ON(efi.memmap.late);
+
+ return __efi_memmap_init(data, false);
+}
+
+void __init efi_memmap_unmap(void)
+{
+ if (!efi_enabled(EFI_MEMMAP))
+ return;
+
+ if (!efi.memmap.late) {
+ unsigned long size;
+
+ size = efi.memmap.desc_size * efi.memmap.nr_map;
+ early_memunmap(efi.memmap.map, size);
+ } else {
+ memunmap(efi.memmap.map);
+ }
+
+ efi.memmap.map = NULL;
+ clear_bit(EFI_MEMMAP, &efi.flags);
+}
+
+/**
+ * efi_memmap_init_late - Map efi.memmap with memremap()
+ * @phys_addr: Physical address of the new EFI memory map
+ * @size: Size in bytes of the new EFI memory map
+ *
+ * Setup a mapping of the EFI memory map using ioremap_cache(). This
+ * function should only be called once the vmalloc space has been
+ * setup and is therefore not suitable for calling during early EFI
+ * initialise, e.g. in efi_init(). Additionally, it expects
+ * efi_memmap_init_early() to have already been called.
+ *
+ * The reason there are two EFI memmap initialisation
+ * (efi_memmap_init_early() and this late version) is because the
+ * early EFI memmap should be explicitly unmapped once EFI
+ * initialisation is complete as the fixmap space used to map the EFI
+ * memmap (via early_memremap()) is a scarce resource.
+ *
+ * This late mapping is intended to persist for the duration of
+ * runtime so that things like efi_mem_desc_lookup() and
+ * efi_mem_attributes() always work.
+ *
+ * Returns zero on success, a negative error code on failure.
+ */
+int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size)
+{
+ struct efi_memory_map_data data = {
+ .phys_map = addr,
+ .size = size,
+ };
+
+ /* Did we forget to unmap the early EFI memmap? */
+ WARN_ON(efi.memmap.map);
+
+ /* Were we already called? */
+ WARN_ON(efi.memmap.late);
+
+ /*
+ * It makes no sense to allow callers to register different
+ * values for the following fields. Copy them out of the
+ * existing early EFI memmap.
+ */
+ data.desc_version = efi.memmap.desc_version;
+ data.desc_size = efi.memmap.desc_size;
+
+ return __efi_memmap_init(&data, true);
+}
+
+/**
+ * efi_memmap_install - Install a new EFI memory map in efi.memmap
+ * @addr: Physical address of the memory map
+ * @nr_map: Number of entries in the memory map
+ *
+ * Unlike efi_memmap_init_*(), this function does not allow the caller
+ * to switch from early to late mappings. It simply uses the existing
+ * mapping function and installs the new memmap.
+ *
+ * Returns zero on success, a negative error code on failure.
+ */
+int __init efi_memmap_install(phys_addr_t addr, unsigned int nr_map)
+{
+ struct efi_memory_map_data data;
+
+ efi_memmap_unmap();
+
+ data.phys_map = addr;
+ data.size = efi.memmap.desc_size * nr_map;
+ data.desc_version = efi.memmap.desc_version;
+ data.desc_size = efi.memmap.desc_size;
+
+ return __efi_memmap_init(&data, efi.memmap.late);
+}
+
+/**
+ * efi_memmap_split_count - Count number of additional EFI memmap entries
+ * @md: EFI memory descriptor to split
+ * @range: Address range (start, end) to split around
+ *
+ * Returns the number of additional EFI memmap entries required to
+ * accomodate @range.
+ */
+int __init efi_memmap_split_count(efi_memory_desc_t *md, struct range *range)
+{
+ u64 m_start, m_end;
+ u64 start, end;
+ int count = 0;
+
+ start = md->phys_addr;
+ end = start + (md->num_pages << EFI_PAGE_SHIFT) - 1;
+
+ /* modifying range */
+ m_start = range->start;
+ m_end = range->end;
+
+ if (m_start <= start) {
+ /* split into 2 parts */
+ if (start < m_end && m_end < end)
+ count++;
+ }
+
+ if (start < m_start && m_start < end) {
+ /* split into 3 parts */
+ if (m_end < end)
+ count += 2;
+ /* split into 2 parts */
+ if (end <= m_end)
+ count++;
+ }
+
+ return count;
+}
+
+/**
+ * efi_memmap_insert - Insert a memory region in an EFI memmap
+ * @old_memmap: The existing EFI memory map structure
+ * @buf: Address of buffer to store new map
+ * @mem: Memory map entry to insert
+ *
+ * It is suggested that you call efi_memmap_split_count() first
+ * to see how large @buf needs to be.
+ */
+void __init efi_memmap_insert(struct efi_memory_map *old_memmap, void *buf,
+ struct efi_mem_range *mem)
+{
+ u64 m_start, m_end, m_attr;
+ efi_memory_desc_t *md;
+ u64 start, end;
+ void *old, *new;
+
+ /* modifying range */
+ m_start = mem->range.start;
+ m_end = mem->range.end;
+ m_attr = mem->attribute;
+
+ /*
+ * The EFI memory map deals with regions in EFI_PAGE_SIZE
+ * units. Ensure that the region described by 'mem' is aligned
+ * correctly.
+ */
+ if (!IS_ALIGNED(m_start, EFI_PAGE_SIZE) ||
+ !IS_ALIGNED(m_end + 1, EFI_PAGE_SIZE)) {
+ WARN_ON(1);
+ return;
+ }
+
+ for (old = old_memmap->map, new = buf;
+ old < old_memmap->map_end;
+ old += old_memmap->desc_size, new += old_memmap->desc_size) {
+
+ /* copy original EFI memory descriptor */
+ memcpy(new, old, old_memmap->desc_size);
+ md = new;
+ start = md->phys_addr;
+ end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT) - 1;
+
+ if (m_start <= start && end <= m_end)
+ md->attribute |= m_attr;
+
+ if (m_start <= start &&
+ (start < m_end && m_end < end)) {
+ /* first part */
+ md->attribute |= m_attr;
+ md->num_pages = (m_end - md->phys_addr + 1) >>
+ EFI_PAGE_SHIFT;
+ /* latter part */
+ new += old_memmap->desc_size;
+ memcpy(new, old, old_memmap->desc_size);
+ md = new;
+ md->phys_addr = m_end + 1;
+ md->num_pages = (end - md->phys_addr + 1) >>
+ EFI_PAGE_SHIFT;
+ }
+
+ if ((start < m_start && m_start < end) && m_end < end) {
+ /* first part */
+ md->num_pages = (m_start - md->phys_addr) >>
+ EFI_PAGE_SHIFT;
+ /* middle part */
+ new += old_memmap->desc_size;
+ memcpy(new, old, old_memmap->desc_size);
+ md = new;
+ md->attribute |= m_attr;
+ md->phys_addr = m_start;
+ md->num_pages = (m_end - m_start + 1) >>
+ EFI_PAGE_SHIFT;
+ /* last part */
+ new += old_memmap->desc_size;
+ memcpy(new, old, old_memmap->desc_size);
+ md = new;
+ md->phys_addr = m_end + 1;
+ md->num_pages = (end - m_end) >>
+ EFI_PAGE_SHIFT;
+ }
+
+ if ((start < m_start && m_start < end) &&
+ (end <= m_end)) {
+ /* first part */
+ md->num_pages = (m_start - md->phys_addr) >>
+ EFI_PAGE_SHIFT;
+ /* latter part */
+ new += old_memmap->desc_size;
+ memcpy(new, old, old_memmap->desc_size);
+ md = new;
+ md->phys_addr = m_start;
+ md->num_pages = (end - md->phys_addr + 1) >>
+ EFI_PAGE_SHIFT;
+ md->attribute |= m_attr;
+ }
+ }
+}