From: Ard Biesheuvel <ardb@kernel.org>
Date: Fri, 3 Jan 2020 12:39:39 +0100
Subject: efi/x86: Split off some old memmap handling into separate routines
Patch-mainline: v5.6-rc1
Git-commit: 98dd0e3a0ceebd594942777e4aca9791177e3f2b
References: jsc#SLE-16407
In a subsequent patch, we will fold the prolog/epilog routines that are
part of the support code to call SetVirtualAddressMap() with a 1:1
mapping into the callers. However, the 64-bit version mostly consists
of ugly mapping code that is only used when efi=old_map is in effect,
which is extremely rare. So let's move this code out of the way so it
does not clutter the common code.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arvind Sankar <nivedita@alum.mit.edu>
Cc: Matthew Garrett <mjg59@google.com>
Cc: linux-efi@vger.kernel.org
Link: https://lkml.kernel.org/r/20200103113953.9571-7-ardb@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
arch/x86/platform/efi/efi_64.c | 35 ++++++++++++++++++++++-------------
1 file changed, 22 insertions(+), 13 deletions(-)
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -72,7 +72,9 @@ static void __init early_code_mapping_se
}
}
-pgd_t * __init efi_call_phys_prolog(void)
+void __init efi_old_memmap_phys_epilog(pgd_t *save_pgd);
+
+pgd_t * __init efi_old_memmap_phys_prolog(void)
{
unsigned long vaddr, addr_pgd, addr_p4d, addr_pud;
pgd_t *save_pgd, *pgd_k, *pgd_efi;
@@ -82,11 +84,6 @@ pgd_t * __init efi_call_phys_prolog(void
int pgd;
int n_pgds, i, j;
- if (!efi_enabled(EFI_OLD_MEMMAP)) {
- efi_switch_mm(&efi_mm);
- return efi_mm.pgd;
- }
-
early_code_mapping_set_exec(1);
n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE);
@@ -143,11 +140,11 @@ pgd_t * __init efi_call_phys_prolog(void
__flush_tlb_all();
return save_pgd;
out:
- efi_call_phys_epilog(save_pgd);
+ efi_old_memmap_phys_epilog(save_pgd);
return NULL;
}
-void __init efi_call_phys_epilog(pgd_t *save_pgd)
+void __init efi_old_memmap_phys_epilog(pgd_t *save_pgd)
{
/*
* After the lock is released, the original page table is restored.
@@ -158,11 +155,6 @@ void __init efi_call_phys_epilog(pgd_t *
p4d_t *p4d;
pud_t *pud;
- if (!efi_enabled(EFI_OLD_MEMMAP)) {
- efi_switch_mm(efi_scratch.prev_mm);
- return;
- }
-
nr_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE);
for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++) {
@@ -193,6 +185,23 @@ void __init efi_call_phys_epilog(pgd_t *
early_code_mapping_set_exec(0);
}
+pgd_t * __init efi_call_phys_prolog(void)
+{
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ return efi_old_memmap_phys_prolog();
+
+ efi_switch_mm(&efi_mm);
+ return efi_mm.pgd;
+}
+
+void __init efi_call_phys_epilog(pgd_t *save_pgd)
+{
+ if (efi_enabled(EFI_OLD_MEMMAP))
+ efi_old_memmap_phys_epilog(save_pgd);
+ else
+ efi_switch_mm(efi_scratch.prev_mm);
+}
+
EXPORT_SYMBOL_GPL(efi_mm);
/*