From 98dd0e3a0ceebd594942777e4aca9791177e3f2b Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 3 Jan 2020 12:39:39 +0100 Subject: 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 Cc: Andy Lutomirski Cc: Ard Biesheuvel Cc: Arvind Sankar Cc: Matthew Garrett Cc: linux-efi@vger.kernel.org Link: https://lkml.kernel.org/r/20200103113953.9571-7-ardb@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/platform/efi/efi_64.c | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-) (limited to 'arch/x86/platform/efi/efi_64.c') diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 03c2ed3c645c..a72bbabbc595 100644 --- 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_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); /* -- cgit