4 files changed, 42 insertions, 4 deletions

diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
index 10aca63a50d7..30031d5293c4 100644
--- a/arch/x86/platform/efi/quirks.c
+++ b/arch/x86/platform/efi/quirks.c
@@ -214,7 +214,7 @@ void __init efi_arch_mem_reserve(phys_addr_t addr, u64 size)
 
         new_size = efi.memmap.desc_size * num_entries;
 
-        new_phys = memblock_alloc(new_size, 0);
+        new_phys = efi_memmap_alloc(num_entries);
         if (!new_phys) {
                 pr_err("Could not allocate boot services memmap\n");
                 return;
@@ -355,7 +355,7 @@ void __init efi_free_boot_services(void)
         }
 
         new_size = efi.memmap.desc_size * num_entries;
-        new_phys = memblock_alloc(new_size, 0);
+        new_phys = efi_memmap_alloc(num_entries);
         if (!new_phys) {
                 pr_err("Failed to allocate new EFI memmap\n");
                 return;
diff --git a/drivers/firmware/efi/fake_mem.c b/drivers/firmware/efi/fake_mem.c
index 520a40e5e0e4..6c7d60c239b5 100644
--- a/drivers/firmware/efi/fake_mem.c
+++ b/drivers/firmware/efi/fake_mem.c
@@ -71,8 +71,7 @@ void __init efi_fake_memmap(void)
         }
 
         /* allocate memory for new EFI memmap */
-        new_memmap_phy = memblock_alloc(efi.memmap.desc_size * new_nr_map,
-                                        PAGE_SIZE);
+        new_memmap_phy = efi_memmap_alloc(new_nr_map);
         if (!new_memmap_phy)
                 return;
 
diff --git a/drivers/firmware/efi/memmap.c b/drivers/firmware/efi/memmap.c
index f03ddecd232b..78686443cb37 100644
--- a/drivers/firmware/efi/memmap.c
+++ b/drivers/firmware/efi/memmap.c
@@ -9,6 +9,44 @@
 #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
diff --git a/include/linux/efi.h b/include/linux/efi.h
index fda79cdf9f10..cba7177cbec7 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -931,6 +931,7 @@ static inline efi_status_t efi_query_variable_store(u32 attributes,
 #endif
 extern void __iomem *efi_lookup_mapped_addr(u64 phys_addr);
 
+extern phys_addr_t __init efi_memmap_alloc(unsigned int num_entries);
 extern int __init efi_memmap_init_early(struct efi_memory_map_data *data);
 extern int __init efi_memmap_init_late(phys_addr_t addr, unsigned long size);
 extern void __init efi_memmap_unmap(void);