[PATCH 2/5] x86/efi: Replace efi_pgd with efi_mm.pgd

From: Ard Biesheuvel
Date: Mon Mar 12 2018 - 04:46:11 EST


From: Sai Praneeth <sai.praneeth.prakhya@xxxxxxxxx>

Since the previous patch added support for efi_mm, let's handle efi_pgd
through efi_mm and remove global variable efi_pgd.

Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@xxxxxxxxx>
Cc: "Lee, Chun-Yi" <jlee@xxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Michael S. Tsirkin <mst@xxxxxxxxxx>
Cc: Bhupesh Sharma <bhsharma@xxxxxxxxxx>
Cc: Ricardo Neri <ricardo.neri@xxxxxxxxx>
Cc: Ravi Shankar <ravi.v.shankar@xxxxxxxxx>
Tested-by: Bhupesh Sharma <bhsharma@xxxxxxxxxx>
Reviewed-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
---
arch/x86/platform/efi/efi_64.c | 17 ++++++++---------
1 file changed, 8 insertions(+), 9 deletions(-)

diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c
index 0045efe9947b..8881e601c32d 100644
--- a/arch/x86/platform/efi/efi_64.c
+++ b/arch/x86/platform/efi/efi_64.c
@@ -190,8 +190,6 @@ void __init efi_call_phys_epilog(pgd_t *save_pgd)
early_code_mapping_set_exec(0);
}

-static pgd_t *efi_pgd;
-
/*
* We need our own copy of the higher levels of the page tables
* because we want to avoid inserting EFI region mappings (EFI_VA_END
@@ -203,7 +201,7 @@ static pgd_t *efi_pgd;
*/
int __init efi_alloc_page_tables(void)
{
- pgd_t *pgd;
+ pgd_t *pgd, *efi_pgd;
p4d_t *p4d;
pud_t *pud;
gfp_t gfp_mask;
@@ -231,6 +229,7 @@ int __init efi_alloc_page_tables(void)
return -ENOMEM;
}

+ efi_mm.pgd = efi_pgd;
mm_init_cpumask(&efi_mm);
init_new_context(NULL, &efi_mm);

@@ -246,6 +245,7 @@ void efi_sync_low_kernel_mappings(void)
pgd_t *pgd_k, *pgd_efi;
p4d_t *p4d_k, *p4d_efi;
pud_t *pud_k, *pud_efi;
+ pgd_t *efi_pgd = efi_mm.pgd;

if (efi_enabled(EFI_OLD_MEMMAP))
return;
@@ -339,7 +339,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
unsigned long pfn, text, pf;
struct page *page;
unsigned npages;
- pgd_t *pgd;
+ pgd_t *pgd = efi_mm.pgd;

if (efi_enabled(EFI_OLD_MEMMAP))
return 0;
@@ -349,8 +349,7 @@ int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
* this value is loaded into cr3 the PGD will be decrypted during
* the pagetable walk.
*/
- efi_scratch.efi_pgt = (pgd_t *)__sme_pa(efi_pgd);
- pgd = efi_pgd;
+ efi_scratch.efi_pgt = (pgd_t *)__sme_pa(pgd);

/*
* It can happen that the physical address of new_memmap lands in memory
@@ -420,7 +419,7 @@ static void __init __map_region(efi_memory_desc_t *md, u64 va)
{
unsigned long flags = _PAGE_RW;
unsigned long pfn;
- pgd_t *pgd = efi_pgd;
+ pgd_t *pgd = efi_mm.pgd;

if (!(md->attribute & EFI_MEMORY_WB))
flags |= _PAGE_PCD;
@@ -524,7 +523,7 @@ void __init parse_efi_setup(u64 phys_addr, u32 data_len)
static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf)
{
unsigned long pfn;
- pgd_t *pgd = efi_pgd;
+ pgd_t *pgd = efi_mm.pgd;
int err1, err2;

/* Update the 1:1 mapping */
@@ -621,7 +620,7 @@ void __init efi_dump_pagetable(void)
if (efi_enabled(EFI_OLD_MEMMAP))
ptdump_walk_pgd_level(NULL, swapper_pg_dir);
else
- ptdump_walk_pgd_level(NULL, efi_pgd);
+ ptdump_walk_pgd_level(NULL, efi_mm.pgd);
#endif
}

--
2.15.1