[tip:x86/boot] x86/boot: Split out kernel_ident_mapping_init()
From: tip-bot for Yinghai Lu
Date: Sat May 07 2016 - 02:38:13 EST
Commit-ID: cf4fb15b3110df070fe9829a1ef38fef8316fb90
Gitweb: http://git.kernel.org/tip/cf4fb15b3110df070fe9829a1ef38fef8316fb90
Author: Yinghai Lu <yinghai@xxxxxxxxxx>
AuthorDate: Fri, 6 May 2016 15:01:34 -0700
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Sat, 7 May 2016 07:38:39 +0200
x86/boot: Split out kernel_ident_mapping_init()
In order to support on-demand page table creation when moving the
kernel for KASLR, we need to use kernel_ident_mapping_init() in the
decompression code.
This splits it out into its own file for use outside of init_64.c.
Additionally, checking for __pa/__va defines is added since they
need to be overridden in the decompression code.
[kees: rewrote changelog]
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Baoquan He <bhe@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxx>
Cc: Brian Gerst <brgerst@xxxxxxxxx>
Cc: Dave Young <dyoung@xxxxxxxxxx>
Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vivek Goyal <vgoyal@xxxxxxxxxx>
Cc: kernel-hardening@xxxxxxxxxxxxxxxxxx
Cc: lasse.collin@xxxxxxxxxxx
Link: http://lkml.kernel.org/r/1462572095-11754-3-git-send-email-keescook@xxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/include/asm/page.h | 5 +++
arch/x86/mm/ident_map.c | 74 +++++++++++++++++++++++++++++++++++++++++++++
arch/x86/mm/init_64.c | 74 +--------------------------------------------
3 files changed, 80 insertions(+), 73 deletions(-)
diff --git a/arch/x86/include/asm/page.h b/arch/x86/include/asm/page.h
index 802dde3..cf8f619 100644
--- a/arch/x86/include/asm/page.h
+++ b/arch/x86/include/asm/page.h
@@ -37,7 +37,10 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
alloc_page_vma(GFP_HIGHUSER | __GFP_ZERO | movableflags, vma, vaddr)
#define __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
+#ifndef __pa
#define __pa(x) __phys_addr((unsigned long)(x))
+#endif
+
#define __pa_nodebug(x) __phys_addr_nodebug((unsigned long)(x))
/* __pa_symbol should be used for C visible symbols.
This seems to be the official gcc blessed way to do such arithmetic. */
@@ -51,7 +54,9 @@ static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
#define __pa_symbol(x) \
__phys_addr_symbol(__phys_reloc_hide((unsigned long)(x)))
+#ifndef __va
#define __va(x) ((void *)((unsigned long)(x)+PAGE_OFFSET))
+#endif
#define __boot_va(x) __va(x)
#define __boot_pa(x) __pa(x)
diff --git a/arch/x86/mm/ident_map.c b/arch/x86/mm/ident_map.c
new file mode 100644
index 0000000..751ca92
--- /dev/null
+++ b/arch/x86/mm/ident_map.c
@@ -0,0 +1,74 @@
+
+static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
+ unsigned long addr, unsigned long end)
+{
+ addr &= PMD_MASK;
+ for (; addr < end; addr += PMD_SIZE) {
+ pmd_t *pmd = pmd_page + pmd_index(addr);
+
+ if (!pmd_present(*pmd))
+ set_pmd(pmd, __pmd(addr | pmd_flag));
+ }
+}
+static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
+ unsigned long addr, unsigned long end)
+{
+ unsigned long next;
+
+ for (; addr < end; addr = next) {
+ pud_t *pud = pud_page + pud_index(addr);
+ pmd_t *pmd;
+
+ next = (addr & PUD_MASK) + PUD_SIZE;
+ if (next > end)
+ next = end;
+
+ if (pud_present(*pud)) {
+ pmd = pmd_offset(pud, 0);
+ ident_pmd_init(info->pmd_flag, pmd, addr, next);
+ continue;
+ }
+ pmd = (pmd_t *)info->alloc_pgt_page(info->context);
+ if (!pmd)
+ return -ENOMEM;
+ ident_pmd_init(info->pmd_flag, pmd, addr, next);
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
+ }
+
+ return 0;
+}
+
+int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
+ unsigned long addr, unsigned long end)
+{
+ unsigned long next;
+ int result;
+ int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
+
+ for (; addr < end; addr = next) {
+ pgd_t *pgd = pgd_page + pgd_index(addr) + off;
+ pud_t *pud;
+
+ next = (addr & PGDIR_MASK) + PGDIR_SIZE;
+ if (next > end)
+ next = end;
+
+ if (pgd_present(*pgd)) {
+ pud = pud_offset(pgd, 0);
+ result = ident_pud_init(info, pud, addr, next);
+ if (result)
+ return result;
+ continue;
+ }
+
+ pud = (pud_t *)info->alloc_pgt_page(info->context);
+ if (!pud)
+ return -ENOMEM;
+ result = ident_pud_init(info, pud, addr, next);
+ if (result)
+ return result;
+ set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
+ }
+
+ return 0;
+}
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 214afda..65cfbee 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -58,79 +58,7 @@
#include "mm_internal.h"
-static void ident_pmd_init(unsigned long pmd_flag, pmd_t *pmd_page,
- unsigned long addr, unsigned long end)
-{
- addr &= PMD_MASK;
- for (; addr < end; addr += PMD_SIZE) {
- pmd_t *pmd = pmd_page + pmd_index(addr);
-
- if (!pmd_present(*pmd))
- set_pmd(pmd, __pmd(addr | pmd_flag));
- }
-}
-static int ident_pud_init(struct x86_mapping_info *info, pud_t *pud_page,
- unsigned long addr, unsigned long end)
-{
- unsigned long next;
-
- for (; addr < end; addr = next) {
- pud_t *pud = pud_page + pud_index(addr);
- pmd_t *pmd;
-
- next = (addr & PUD_MASK) + PUD_SIZE;
- if (next > end)
- next = end;
-
- if (pud_present(*pud)) {
- pmd = pmd_offset(pud, 0);
- ident_pmd_init(info->pmd_flag, pmd, addr, next);
- continue;
- }
- pmd = (pmd_t *)info->alloc_pgt_page(info->context);
- if (!pmd)
- return -ENOMEM;
- ident_pmd_init(info->pmd_flag, pmd, addr, next);
- set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
- }
-
- return 0;
-}
-
-int kernel_ident_mapping_init(struct x86_mapping_info *info, pgd_t *pgd_page,
- unsigned long addr, unsigned long end)
-{
- unsigned long next;
- int result;
- int off = info->kernel_mapping ? pgd_index(__PAGE_OFFSET) : 0;
-
- for (; addr < end; addr = next) {
- pgd_t *pgd = pgd_page + pgd_index(addr) + off;
- pud_t *pud;
-
- next = (addr & PGDIR_MASK) + PGDIR_SIZE;
- if (next > end)
- next = end;
-
- if (pgd_present(*pgd)) {
- pud = pud_offset(pgd, 0);
- result = ident_pud_init(info, pud, addr, next);
- if (result)
- return result;
- continue;
- }
-
- pud = (pud_t *)info->alloc_pgt_page(info->context);
- if (!pud)
- return -ENOMEM;
- result = ident_pud_init(info, pud, addr, next);
- if (result)
- return result;
- set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
- }
-
- return 0;
-}
+#include "ident_map.c"
/*
* NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the