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#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_x86_reserve_range(mem, mem + size, "TRAMPOLINE");
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);
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