Merge tag 'for-3.8' of git://openrisc.net/~jonas/linux

[deliverable/linux.git] / arch / x86 / kernel / tboot.c

diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
index d4f460f962ee35d5202894223cc36732524f051f..f84fe00fad48a4e1c2273a9f46a18b47af96204c 100644 (file)
--- a/arch/x86/kernel/tboot.c
+++ b/arch/x86/kernel/tboot.c
@@ -103,13 +103,71 @@ 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)
 {
-#ifdef CONFIG_X86_32
-       load_cr3(initial_page_table);
-#else
-       write_cr3(real_mode_header->trampoline_pgd);
-#endif
+       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_ACPI_SLEEP
@@ -167,6 +225,14 @@ 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())
@@ -277,6 +343,8 @@ 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);