efi/x86: Split off some old memmap handling into separate routines

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>
This commit is contained in:
Ard Biesheuvel 2020-01-03 12:39:39 +01:00 committed by Ingo Molnar
parent 89ed486532
commit 98dd0e3a0c
1 changed files with 22 additions and 13 deletions

View File

@ -72,7 +72,9 @@ static void __init early_code_mapping_set_exec(int executable)
}
}
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 *save_pgd)
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 *save_pgd)
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);
/*