x86, realmode: don't copy real_mode_header

[cascardo/linux.git] / arch / x86 / kernel / realmode.c

diff --git a/arch/x86/kernel/realmode.c b/arch/x86/kernel/realmode.c
index e7bf82a..632c810 100644 (file)
--- a/arch/x86/kernel/realmode.c
+++ b/arch/x86/kernel/realmode.c
@@ -5,8 +5,7 @@
 #include <asm/pgtable.h>
 #include <asm/realmode.h>
 
-unsigned char *real_mode_base;
-struct real_mode_header real_mode_header;
+struct real_mode_header *real_mode_header;
 
 void __init setup_real_mode(void)
 {
@@ -17,33 +16,32 @@ void __init setup_real_mode(void)
        u32 *ptr;
        u16 *seg;
        int i;
+       unsigned char *base;
 
-       struct real_mode_header *header =
-               (struct real_mode_header *) real_mode_blob;
-
-       size_t size = PAGE_ALIGN(header->end);
+       size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);
 
        /* Has to be in very low memory so we can execute real-mode AP code. */
        mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
        if (!mem)
                panic("Cannot allocate trampoline\n");
 
-       real_mode_base = __va(mem);
+       base = __va(mem);
        memblock_reserve(mem, size);
+       real_mode_header = (struct real_mode_header *) base;
 
        printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n",
-              real_mode_base, (unsigned long long)mem, size);
+              base, (unsigned long long)mem, size);
 
-       memcpy(real_mode_base, real_mode_blob, size);
+       memcpy(base, real_mode_blob, size);
 
-       real_mode_seg = __pa(real_mode_base) >> 4;
+       real_mode_seg = __pa(base) >> 4;
        rel = (u32 *) real_mode_relocs;
 
        /* 16-bit segment relocations. */
        count = rel[0];
        rel = &rel[1];
        for (i = 0; i < count; i++) {
-               seg = (u16 *) (real_mode_base + rel[i]);
+               seg = (u16 *) (base + rel[i]);
                *seg = real_mode_seg;
        }
 
@@ -51,25 +49,21 @@ void __init setup_real_mode(void)
        count = rel[i];
        rel =  &rel[i + 1];
        for (i = 0; i < count; i++) {
-               ptr = (u32 *) (real_mode_base + rel[i]);
-               *ptr += __pa(real_mode_base);
+               ptr = (u32 *) (base + rel[i]);
+               *ptr += __pa(base);
        }
 
-       /* Copied header will contain relocated physical addresses. */
-       memcpy(&real_mode_header, real_mode_base,
-              sizeof(struct real_mode_header));
-
 #ifdef CONFIG_X86_32
-       *((u32 *)__va(real_mode_header.startup_32_smp)) = __pa(startup_32_smp);
-       *((u32 *)__va(real_mode_header.boot_gdt)) = __pa(boot_gdt);
+       *((u32 *)__va(real_mode_header->startup_32_smp)) = __pa(startup_32_smp);
+       *((u32 *)__va(real_mode_header->boot_gdt)) = __pa(boot_gdt);
 #else
-       *((u64 *) __va(real_mode_header.startup_64_smp)) =
+       *((u64 *) __va(real_mode_header->startup_64_smp)) =
                (u64)secondary_startup_64;
 
-       *((u64 *) __va(real_mode_header.level3_ident_pgt)) =
+       *((u64 *) __va(real_mode_header->level3_ident_pgt)) =
                __pa(level3_ident_pgt) + _KERNPG_TABLE;
 
-       *((u64 *) __va(real_mode_header.level3_kernel_pgt)) =
+       *((u64 *) __va(real_mode_header->level3_kernel_pgt)) =
                __pa(level3_kernel_pgt) + _KERNPG_TABLE;
 #endif
 }
@@ -82,23 +76,22 @@ void __init setup_real_mode(void)
  */
 static int __init set_real_mode_permissions(void)
 {
-       size_t all_size =
-               PAGE_ALIGN(real_mode_header.end) -
-               __pa(real_mode_base);
+       unsigned char *base = (unsigned char *) real_mode_header;
+       size_t size = PAGE_ALIGN(real_mode_blob_end - real_mode_blob);
 
        size_t ro_size =
-               PAGE_ALIGN(real_mode_header.ro_end) -
-               __pa(real_mode_base);
+               PAGE_ALIGN(real_mode_header->ro_end) -
+               __pa(base);
 
        size_t text_size =
-               PAGE_ALIGN(real_mode_header.ro_end) -
-               real_mode_header.text_start;
+               PAGE_ALIGN(real_mode_header->ro_end) -
+               real_mode_header->text_start;
 
        unsigned long text_start =
-               (unsigned long) __va(real_mode_header.text_start);
+               (unsigned long) __va(real_mode_header->text_start);
 
-       set_memory_nx((unsigned long) real_mode_base, all_size >> PAGE_SHIFT);
-       set_memory_ro((unsigned long) real_mode_base, ro_size >> PAGE_SHIFT);
+       set_memory_nx((unsigned long) base, size >> PAGE_SHIFT);
+       set_memory_ro((unsigned long) base, ro_size >> PAGE_SHIFT);
        set_memory_x((unsigned long) text_start, text_size >> PAGE_SHIFT);
 
        return 0;