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authorXiaoyan Zhang <xiaoyan.zhang@intel.com>2012-09-07 19:29:04 +0100
committerMatt Fleming <matt.fleming@intel.com>2012-10-30 10:39:20 +0000
commitda5a108d05b4f350be33e62d2db125673823e7ff (patch)
treeadae6b32a6c59f4a9d553b1fb6dff720b07a145c
parent185034e72d591f9465e5e18f937ed642e7ea0070 (diff)
x86/kernel: remove tboot 1:1 page table creation code
For TXT boot, while Linux kernel trys to shutdown/S3/S4/reboot, it need to jump back to tboot code and do TXT teardown work. Previously kernel zapped all mem page identity mapping (va=pa) after booting, so tboot code mem address was mapped again with identity mapping. Now kernel didn't zap the identity mapping page table, so tboot related code can remove the remapping code before trapping back now. Signed-off-by: Xiaoyan Zhang <xiaoyan.zhang@intel.com> Acked-by: Gang Wei <gang.wei@intel.com> Signed-off-by: Matt Fleming <matt.fleming@intel.com>
-rw-r--r--arch/x86/kernel/tboot.c78
1 files changed, 5 insertions, 73 deletions
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index f84fe00fad4..d4f460f962e 100644
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -103,71 +103,13 @@ void __init tboot_probe(void)
pr_debug("tboot_size: 0x%x\n", tboot->tboot_size);
}
-static pgd_t *tboot_pg_dir;
-static struct mm_struct tboot_mm = {
- .mm_rb = RB_ROOT,
- .pgd = swapper_pg_dir,
- .mm_users = ATOMIC_INIT(2),
- .mm_count = ATOMIC_INIT(1),
- .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem),
- .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
- .mmlist = LIST_HEAD_INIT(init_mm.mmlist),
-};
-
static inline void switch_to_tboot_pt(void)
{
- write_cr3(virt_to_phys(tboot_pg_dir));
-}
-
-static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
- pgprot_t prot)
-{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
-
- pgd = pgd_offset(&tboot_mm, vaddr);
- pud = pud_alloc(&tboot_mm, pgd, vaddr);
- if (!pud)
- return -1;
- pmd = pmd_alloc(&tboot_mm, pud, vaddr);
- if (!pmd)
- return -1;
- pte = pte_alloc_map(&tboot_mm, NULL, pmd, vaddr);
- if (!pte)
- return -1;
- set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
- pte_unmap(pte);
- return 0;
-}
-
-static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
- unsigned long nr)
-{
- /* Reuse the original kernel mapping */
- tboot_pg_dir = pgd_alloc(&tboot_mm);
- if (!tboot_pg_dir)
- return -1;
-
- for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) {
- if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC))
- return -1;
- }
-
- return 0;
-}
-
-static void tboot_create_trampoline(void)
-{
- u32 map_base, map_size;
-
- /* Create identity map for tboot shutdown code. */
- map_base = PFN_DOWN(tboot->tboot_base);
- map_size = PFN_UP(tboot->tboot_size);
- if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
- panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n",
- map_base, map_size);
+#ifdef CONFIG_X86_32
+ load_cr3(initial_page_table);
+#else
+ write_cr3(real_mode_header->trampoline_pgd);
+#endif
}
#ifdef CONFIG_ACPI_SLEEP
@@ -225,14 +167,6 @@ void tboot_shutdown(u32 shutdown_type)
if (!tboot_enabled())
return;
- /*
- * if we're being called before the 1:1 mapping is set up then just
- * return and let the normal shutdown happen; this should only be
- * due to very early panic()
- */
- if (!tboot_pg_dir)
- return;
-
/* if this is S3 then set regions to MAC */
if (shutdown_type == TB_SHUTDOWN_S3)
if (tboot_setup_sleep())
@@ -343,8 +277,6 @@ static __init int tboot_late_init(void)
if (!tboot_enabled())
return 0;
- tboot_create_trampoline();
-
atomic_set(&ap_wfs_count, 0);
register_hotcpu_notifier(&tboot_cpu_notifier);