diff options
Diffstat (limited to 'arch/x86/mm/init.c')
| -rw-r--r-- | arch/x86/mm/init.c | 120 |
1 files changed, 109 insertions, 11 deletions
diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c index 7b961d0b1389..bb44e9f2cc49 100644 --- a/arch/x86/mm/init.c +++ b/arch/x86/mm/init.c @@ -243,6 +243,38 @@ static unsigned long __init calculate_table_space_size(unsigned long start, unsi return tables; } +static unsigned long __init calculate_all_table_space_size(void) +{ + unsigned long start_pfn, end_pfn; + unsigned long tables; + int i; + + /* the ISA range is always mapped regardless of memory holes */ + tables = calculate_table_space_size(0, ISA_END_ADDRESS); + + for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, NULL) { + u64 start = start_pfn << PAGE_SHIFT; + u64 end = end_pfn << PAGE_SHIFT; + + if (end <= ISA_END_ADDRESS) + 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) + continue; + + if ((end >> PAGE_SHIFT) > max_low_pfn) + end = max_low_pfn << PAGE_SHIFT; +#endif + tables += calculate_table_space_size(start, end); + } + + return tables; +} + static void __init find_early_table_space(unsigned long start, unsigned long good_end, unsigned long tables) @@ -258,6 +290,34 @@ static void __init find_early_table_space(unsigned long start, pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT); } +static struct range pfn_mapped[E820_X_MAX]; +static int nr_pfn_mapped; + +static void add_pfn_range_mapped(unsigned long start_pfn, unsigned long end_pfn) +{ + nr_pfn_mapped = add_range_with_merge(pfn_mapped, E820_X_MAX, + nr_pfn_mapped, start_pfn, end_pfn); + nr_pfn_mapped = clean_sort_range(pfn_mapped, E820_X_MAX); + + max_pfn_mapped = max(max_pfn_mapped, end_pfn); + + if (start_pfn < (1UL<<(32-PAGE_SHIFT))) + max_low_pfn_mapped = max(max_low_pfn_mapped, + min(end_pfn, 1UL<<(32-PAGE_SHIFT))); +} + +bool pfn_range_is_mapped(unsigned long start_pfn, unsigned long end_pfn) +{ + int i; + + for (i = 0; i < nr_pfn_mapped; i++) + if ((start_pfn >= pfn_mapped[i].start) && + (end_pfn <= pfn_mapped[i].end)) + return true; + + return false; +} + /* * Setup the direct mapping of the physical memory at PAGE_OFFSET. * This runs before bootmem is initialized and gets pages directly from @@ -288,9 +348,55 @@ unsigned long __init_refok init_memory_mapping(unsigned long start, __flush_tlb_all(); + add_pfn_range_mapped(start >> PAGE_SHIFT, ret >> PAGE_SHIFT); + return ret >> PAGE_SHIFT; } +/* + * Iterate through E820 memory map and create direct mappings for only E820_RAM + * regions. We cannot simply create direct mappings for all pfns from + * [0 to max_low_pfn) and [4GB to max_pfn) because of possible memory holes in + * high addresses that cannot be marked as UC by fixed/variable range MTRRs. + * 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) +{ + 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) + 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) + continue; + + if ((end >> PAGE_SHIFT) > max_low_pfn) + end = max_low_pfn << PAGE_SHIFT; +#endif + init_memory_mapping(start, end); + } + +#ifdef CONFIG_X86_64 + if (max_pfn > max_low_pfn) { + /* can we preseve max_low_pfn ?*/ + max_low_pfn = max_pfn; + } +#endif +} + void __init init_mem_mapping(void) { unsigned long tables, good_end, end; @@ -311,23 +417,15 @@ void __init init_mem_mapping(void) end = max_low_pfn << PAGE_SHIFT; good_end = max_pfn_mapped << PAGE_SHIFT; #endif - tables = calculate_table_space_size(0, end); + tables = calculate_all_table_space_size(); find_early_table_space(0, good_end, tables); printk(KERN_DEBUG "kernel direct mapping tables up to %#lx @ [mem %#010lx-%#010lx] prealloc\n", end - 1, pgt_buf_start << PAGE_SHIFT, (pgt_buf_top << PAGE_SHIFT) - 1); - max_low_pfn_mapped = init_memory_mapping(0, max_low_pfn<<PAGE_SHIFT); - max_pfn_mapped = max_low_pfn_mapped; + max_pfn_mapped = 0; /* will get exact value next */ + init_all_memory_mapping(); -#ifdef CONFIG_X86_64 - if (max_pfn > max_low_pfn) { - max_pfn_mapped = init_memory_mapping(1UL<<32, - max_pfn<<PAGE_SHIFT); - /* 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) |