Create initial page tables in init_pg_dir and then create final
page tables in swapper_pg_dir directly.
Signed-off-by: Jun Yao <yaojun8558...@gmail.com>
---
arch/arm64/include/asm/pgtable.h | 2 ++
arch/arm64/kernel/head.S | 4 ++--
arch/arm64/kernel/setup.c | 1 +
arch/arm64/mm/mmu.c | 24 ++++--------------------
4 files changed, 9 insertions(+), 22 deletions(-)
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 7c4c8f318ba9..3b408f21fe2e 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -718,6 +718,8 @@ static inline pmd_t pmdp_establish(struct vm_area_struct
*vma,
}
#endif
+extern pgd_t init_pg_dir[PTRS_PER_PGD] __section(.init.data);
+extern pgd_t init_pg_end[] __section(.init.data);
extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern pgd_t swapper_pg_end[];
extern pgd_t idmap_pg_dir[PTRS_PER_PGD];
diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index a1c7a4d3b9f3..a8e9432ffa8a 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -380,7 +380,7 @@ __create_page_tables:
/*
* Map the kernel image (starting with PHYS_OFFSET).
*/
- adrp x0, swapper_pg_dir
+ adrp x0, init_pg_dir
mov_q x5, KIMAGE_VADDR + TEXT_OFFSET // compile time __va(_text)
add x5, x5, x23 // add KASLR displacement
mov x4, PTRS_PER_PGD
@@ -837,7 +837,7 @@ __primary_switch:
mrs x20, sctlr_el1 // preserve old SCTLR_EL1 value
#endif
- adrp x26, swapper_pg_dir
+ adrp x26, init_pg_dir
bl __enable_mmu
#ifdef CONFIG_RELOCATABLE
bl __relocate_kernel
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 30ad2f085d1f..b065c08d4008 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -249,6 +249,7 @@ void __init setup_arch(char **cmdline_p)
init_mm.end_code = (unsigned long) _etext;
init_mm.end_data = (unsigned long) _edata;
init_mm.brk = (unsigned long) _end;
+ init_mm.pgd = init_pg_dir;
*cmdline_p = boot_command_line;
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 2dbb2c9f1ec1..a7ab0010ff80 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -628,26 +628,10 @@ static void __init map_kernel(pgd_t *pgdp)
*/
void __init paging_init(void)
{
- phys_addr_t pgd_phys = early_pgtable_alloc();
- pgd_t *pgdp = pgd_set_fixmap(pgd_phys);
-
- map_kernel(pgdp);
- map_mem(pgdp);
-
- /*
- * We want to reuse the original swapper_pg_dir so we don't have to
- * communicate the new address to non-coherent secondaries in
- * secondary_entry, and so cpu_switch_mm can generate the address with
- * adrp+add rather than a load from some global variable.
- *
- * To do this we need to go via a temporary pgd.
- */
- cpu_replace_ttbr1(__va(pgd_phys));
- memcpy(swapper_pg_dir, pgdp, PGD_SIZE);
- cpu_replace_ttbr1(lm_alias(swapper_pg_dir));
-
- pgd_clear_fixmap();
- memblock_free(pgd_phys, PAGE_SIZE);
+ map_kernel(swapper_pg_dir);
+ map_mem(swapper_pg_dir);
+ cpu_replace_ttbr1(swapper_pg_dir);
+ init_mm.pgd = swapper_pg_dir;
/*
* We only reuse the PGD from the swapper_pg_dir, not the pud + pmd
--
2.17.1
