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		ecacf09f7d
		
	
	
	
	
		
			
			This patch reserves the EFI memory map with reserve_early(). Because EFI memory map is allocated by bootloader, if it is not reserved by reserved_early(), it may be overwritten through address returned by find_e820_area(). Signed-off-by: Huang Ying <ying.huang@intel.com> Cc: andi@firstfloor.org Cc: mingo@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
		
			
				
	
	
		
			123 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			123 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * x86_64 specific EFI support functions
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|  * Based on Extensible Firmware Interface Specification version 1.0
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|  *
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|  * Copyright (C) 2005-2008 Intel Co.
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|  *	Fenghua Yu <fenghua.yu@intel.com>
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|  *	Bibo Mao <bibo.mao@intel.com>
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|  *	Chandramouli Narayanan <mouli@linux.intel.com>
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|  *	Huang Ying <ying.huang@intel.com>
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|  *
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|  * Code to convert EFI to E820 map has been implemented in elilo bootloader
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|  * based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
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|  * is setup appropriately for EFI runtime code.
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|  * - mouli 06/14/2007.
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|  *
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/init.h>
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| #include <linux/mm.h>
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| #include <linux/types.h>
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| #include <linux/spinlock.h>
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| #include <linux/bootmem.h>
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| #include <linux/ioport.h>
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| #include <linux/module.h>
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| #include <linux/efi.h>
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| #include <linux/uaccess.h>
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| #include <linux/io.h>
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| #include <linux/reboot.h>
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| 
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| #include <asm/setup.h>
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| #include <asm/page.h>
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| #include <asm/e820.h>
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| #include <asm/pgtable.h>
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| #include <asm/tlbflush.h>
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| #include <asm/proto.h>
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| #include <asm/efi.h>
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| #include <asm/cacheflush.h>
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| 
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| static pgd_t save_pgd __initdata;
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| static unsigned long efi_flags __initdata;
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| 
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| static void __init early_mapping_set_exec(unsigned long start,
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| 					  unsigned long end,
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| 					  int executable)
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| {
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| 	unsigned long num_pages;
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| 
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| 	start &= PMD_MASK;
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| 	end = (end + PMD_SIZE - 1) & PMD_MASK;
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| 	num_pages = (end - start) >> PAGE_SHIFT;
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| 	if (executable)
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| 		set_memory_x((unsigned long)__va(start), num_pages);
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| 	else
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| 		set_memory_nx((unsigned long)__va(start), num_pages);
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| }
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| 
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| static void __init early_runtime_code_mapping_set_exec(int executable)
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| {
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| 	efi_memory_desc_t *md;
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| 	void *p;
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| 
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| 	if (!(__supported_pte_mask & _PAGE_NX))
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| 		return;
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| 
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| 	/* Make EFI runtime service code area executable */
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| 	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
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| 		md = p;
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| 		if (md->type == EFI_RUNTIME_SERVICES_CODE) {
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| 			unsigned long end;
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| 			end = md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT);
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| 			early_mapping_set_exec(md->phys_addr, end, executable);
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| 		}
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| 	}
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| }
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| 
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| void __init efi_call_phys_prelog(void)
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| {
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| 	unsigned long vaddress;
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| 
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| 	early_runtime_code_mapping_set_exec(1);
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| 	local_irq_save(efi_flags);
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| 	vaddress = (unsigned long)__va(0x0UL);
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| 	save_pgd = *pgd_offset_k(0x0UL);
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| 	set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress));
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| 	__flush_tlb_all();
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| }
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| 
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| void __init efi_call_phys_epilog(void)
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| {
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| 	/*
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| 	 * After the lock is released, the original page table is restored.
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| 	 */
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| 	set_pgd(pgd_offset_k(0x0UL), save_pgd);
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| 	__flush_tlb_all();
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| 	local_irq_restore(efi_flags);
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| 	early_runtime_code_mapping_set_exec(0);
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| }
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| 
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| void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size)
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| {
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| 	static unsigned pages_mapped __initdata;
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| 	unsigned i, pages;
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| 	unsigned long offset;
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| 
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| 	pages = PFN_UP(phys_addr + size) - PFN_DOWN(phys_addr);
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| 	offset = phys_addr & ~PAGE_MASK;
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| 	phys_addr &= PAGE_MASK;
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| 
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| 	if (pages_mapped + pages > MAX_EFI_IO_PAGES)
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| 		return NULL;
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| 
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| 	for (i = 0; i < pages; i++) {
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| 		__set_fixmap(FIX_EFI_IO_MAP_FIRST_PAGE - pages_mapped,
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| 			     phys_addr, PAGE_KERNEL);
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| 		phys_addr += PAGE_SIZE;
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| 		pages_mapped++;
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| 	}
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| 
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| 	return (void __iomem *)__fix_to_virt(FIX_EFI_IO_MAP_FIRST_PAGE - \
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| 					     (pages_mapped - pages)) + offset;
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| }
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