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>

1 files changed, 1 insertions, 122 deletions

diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index 755e545144ea..4a5d7343dddd 100644
--- 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;