arm64/efi: remove free_boot_services() and friends

Now that we are calling SetVirtualAddressMap() from the stub, there is no
need to reserve boot-only memory regions, which implies that there is also
no reason to free them again later.

Acked-by: Leif Lindholm <leif.lindholm@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index 755e545..4a5d734 100644 (file)
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -199,9 +199,7 @@ static __init void reserve_regions(void)
                if (is_normal_ram(md))
                        early_init_dt_add_memory_arch(paddr, size);
 
-               if (is_reserve_region(md) ||
-                   md->type == EFI_BOOT_SERVICES_CODE ||
-                   md->type == EFI_BOOT_SERVICES_DATA) {
+               if (is_reserve_region(md)) {
                        memblock_reserve(paddr, size);
                        if (uefi_debug)
                                pr_cont("*");
@@ -214,123 +212,6 @@ static __init void reserve_regions(void)
        set_bit(EFI_MEMMAP, &efi.flags);
 }
 
-
-static u64 __init free_one_region(u64 start, u64 end)
-{
-       u64 size = end - start;
-
-       if (uefi_debug)
-               pr_info("  EFI freeing: 0x%012llx-0x%012llx\n", start, end - 1);
-
-       free_bootmem_late(start, size);
-       return size;
-}
-
-static u64 __init free_region(u64 start, u64 end)
-{
-       u64 map_start, map_end, total = 0;
-
-       if (end <= start)
-               return total;
-
-       map_start = (u64)memmap.phys_map;
-       map_end = PAGE_ALIGN(map_start + (memmap.map_end - memmap.map));
-       map_start &= PAGE_MASK;
-
-       if (start < map_end && end > map_start) {
-               /* region overlaps UEFI memmap */
-               if (start < map_start)
-                       total += free_one_region(start, map_start);
-
-               if (map_end < end)
-                       total += free_one_region(map_end, end);
-       } else
-               total += free_one_region(start, end);
-
-       return total;
-}
-
-static void __init free_boot_services(void)
-{
-       u64 total_freed = 0;
-       u64 keep_end, free_start, free_end;
-       efi_memory_desc_t *md;
-
-       /*
-        * If kernel uses larger pages than UEFI, we have to be careful
-        * not to inadvertantly free memory we want to keep if there is
-        * overlap at the kernel page size alignment. We do not want to
-        * free is_reserve_region() memory nor the UEFI memmap itself.
-        *
-        * The memory map is sorted, so we keep track of the end of
-        * any previous region we want to keep, remember any region
-        * we want to free and defer freeing it until we encounter
-        * the next region we want to keep. This way, before freeing
-        * it, we can clip it as needed to avoid freeing memory we
-        * want to keep for UEFI.
-        */
-
-       keep_end = 0;
-       free_start = 0;
-
-       for_each_efi_memory_desc(&memmap, md) {
-               u64 paddr, npages, size;
-
-               if (is_reserve_region(md)) {
-                       /*
-                        * We don't want to free any memory from this region.
-                        */
-                       if (free_start) {
-                               /* adjust free_end then free region */
-                               if (free_end > md->phys_addr)
-                                       free_end -= PAGE_SIZE;
-                               total_freed += free_region(free_start, free_end);
-                               free_start = 0;
-                       }
-                       keep_end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
-                       continue;
-               }
-
-               if (md->type != EFI_BOOT_SERVICES_CODE &&
-                   md->type != EFI_BOOT_SERVICES_DATA) {
-                       /* no need to free this region */
-                       continue;
-               }
-
-               /*
-                * We want to free memory from this region.
-                */
-               paddr = md->phys_addr;
-               npages = md->num_pages;
-               memrange_efi_to_native(&paddr, &npages);
-               size = npages << PAGE_SHIFT;
-
-               if (free_start) {
-                       if (paddr <= free_end)
-                               free_end = paddr + size;
-                       else {
-                               total_freed += free_region(free_start, free_end);
-                               free_start = paddr;
-                               free_end = paddr + size;
-                       }
-               } else {
-                       free_start = paddr;
-                       free_end = paddr + size;
-               }
-               if (free_start < keep_end) {
-                       free_start += PAGE_SIZE;
-                       if (free_start >= free_end)
-                               free_start = 0;
-               }
-       }
-       if (free_start)
-               total_freed += free_region(free_start, free_end);
-
-       if (total_freed)
-               pr_info("Freed 0x%llx bytes of EFI boot services memory",
-                       total_freed);
-}
-
 void __init efi_init(void)
 {
        struct efi_fdt_params params;
@@ -402,8 +283,6 @@ static int __init arm64_enable_runtime_services(void)
        }
        set_bit(EFI_SYSTEM_TABLES, &efi.flags);
 
-       free_boot_services();
-
        if (!efi_enabled(EFI_VIRTMAP)) {
                pr_err("No UEFI virtual mapping was installed -- runtime services will not be available\n");
                return -1;