[PATCH v5 7/8] arm64/efi: remove free_boot_services() and friends

Ard Biesheuvel
2015-01-08T18:48:33Z

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>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
arch/arm64/kernel/efi.c | 123 +-----------------------------------------------
1 file changed, 1 insertion(+), 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;
--
1.8.3.2