diff options
Diffstat (limited to 'ANDROID_3.4.5/arch/x86/kernel/trampoline.c')
-rw-r--r-- | ANDROID_3.4.5/arch/x86/kernel/trampoline.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/ANDROID_3.4.5/arch/x86/kernel/trampoline.c b/ANDROID_3.4.5/arch/x86/kernel/trampoline.c new file mode 100644 index 00000000..a73b6105 --- /dev/null +++ b/ANDROID_3.4.5/arch/x86/kernel/trampoline.c @@ -0,0 +1,42 @@ +#include <linux/io.h> +#include <linux/memblock.h> + +#include <asm/trampoline.h> +#include <asm/cacheflush.h> +#include <asm/pgtable.h> + +unsigned char *x86_trampoline_base; + +void __init setup_trampolines(void) +{ + phys_addr_t mem; + size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start); + + /* 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"); + + x86_trampoline_base = __va(mem); + memblock_reserve(mem, size); + + printk(KERN_DEBUG "Base memory trampoline at [%p] %llx size %zu\n", + x86_trampoline_base, (unsigned long long)mem, size); + + memcpy(x86_trampoline_base, x86_trampoline_start, size); +} + +/* + * setup_trampolines() gets called very early, to guarantee the + * availability of low memory. This is before the proper kernel page + * tables are set up, so we cannot set page permissions in that + * function. Thus, we use an arch_initcall instead. + */ +static int __init configure_trampolines(void) +{ + size_t size = PAGE_ALIGN(x86_trampoline_end - x86_trampoline_start); + + set_memory_x((unsigned long)x86_trampoline_base, size >> PAGE_SHIFT); + return 0; +} +arch_initcall(configure_trampolines); |