x86, mm: Break down init_all_memory_mapping (f763ad1d) · Commits · 戴 / test

arch/x86/mm/init.c

+19 −22

Original line number	Diff line number	Diff line
		@@ -398,40 +398,30 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
		* Depending on the alignment of E820 ranges, this may possibly result in using
		* smaller size (i.e. 4K instead of 2M or 1G) page tables.
		*/
		static void __init init_all_memory_mapping(void)
		static void __init init_range_memory_mapping(unsigned long range_start,
		unsigned long range_end)
		{
		unsigned long start_pfn, end_pfn;
		int i;

		/* the ISA range is always mapped regardless of memory holes */
		init_memory_mapping(0, ISA_END_ADDRESS);

		for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) {
		u64 start = (u64)start_pfn << PAGE_SHIFT;
		u64 end = (u64)end_pfn << PAGE_SHIFT;

		if (end <= ISA_END_ADDRESS)
		if (end <= range_start)
		continue;

		if (start < ISA_END_ADDRESS)
		start = ISA_END_ADDRESS;
		#ifdef CONFIG_X86_32
		/* on 32 bit, we only map up to max_low_pfn */
		if ((start >> PAGE_SHIFT) >= max_low_pfn)
		if (start < range_start)
		start = range_start;

		if (start >= range_end)
		continue;

		if ((end >> PAGE_SHIFT) > max_low_pfn)
		end = max_low_pfn << PAGE_SHIFT;
		#endif
		init_memory_mapping(start, end);
		}
		if (end > range_end)
		end = range_end;

		#ifdef CONFIG_X86_64
		if (max_pfn > max_low_pfn) {
		/* can we preseve max_low_pfn ?*/
		max_low_pfn = max_pfn;
		init_memory_mapping(start, end);
		}
		#endif
		}

		void __init init_mem_mapping(void)
		@@ -461,8 +451,15 @@ void __init init_mem_mapping(void)
		(pgt_buf_top << PAGE_SHIFT) - 1);

		max_pfn_mapped = 0; /* will get exact value next */
		init_all_memory_mapping();

		/* the ISA range is always mapped regardless of memory holes */
		init_memory_mapping(0, ISA_END_ADDRESS);
		init_range_memory_mapping(ISA_END_ADDRESS, end);
		#ifdef CONFIG_X86_64
		if (max_pfn > max_low_pfn) {
		/* can we preseve max_low_pfn ?*/
		max_low_pfn = max_pfn;
		}
		#endif
		/*
		* Reserve the kernel pagetable pages we used (pgt_buf_start -
		* pgt_buf_end) and free the other ones (pgt_buf_end - pgt_buf_top)

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