x86, mm: Separate out calculate_table_space_size()

It should take physical address range that will need to be mapped.
find_early_table_space should take range that pgt buff should be in.

Separating page table size calculating and finding early page table to
reduce confusing.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/1353123563-3103-9-git-send-email-yinghai@kernel.org
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index 1ce0d033fafc7acb87a6e7957ce8edee35144e78..7b961d0b138961fbd55ef5128816a1cdeaa19ab7 100644 (file)
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -196,12 +196,10 @@ static int __meminit split_mem_range(struct map_range *mr, int nr_range,
  * mr[0].start to mr[nr_range - 1].end, while accounting for possible 2M and 1GB
  * pages. Then find enough contiguous space for those page tables.
  */
-static void __init find_early_table_space(unsigned long start, unsigned long end)
+static unsigned long __init calculate_table_space_size(unsigned long start, unsigned long end)
 {
        int i;
        unsigned long puds = 0, pmds = 0, ptes = 0, tables;
-       unsigned long good_end;
-       phys_addr_t base;
        struct map_range mr[NR_RANGE_MR];
        int nr_range;
 
@@ -240,9 +238,17 @@ static void __init find_early_table_space(unsigned long start, unsigned long end
 #ifdef CONFIG_X86_32
        /* for fixmap */
        tables += roundup(__end_of_fixed_addresses * sizeof(pte_t), PAGE_SIZE);
-       good_end = max_pfn_mapped << PAGE_SHIFT;
 #endif
 
+       return tables;
+}
+
+static void __init find_early_table_space(unsigned long start,
+                                         unsigned long good_end,
+                                         unsigned long tables)
+{
+       phys_addr_t base;
+
        base = memblock_find_in_range(start, good_end, tables, PAGE_SIZE);
        if (!base)
                panic("Cannot find space for the kernel page tables");
@@ -250,10 +256,6 @@ static void __init find_early_table_space(unsigned long start, unsigned long end
        pgt_buf_start = base >> PAGE_SHIFT;
        pgt_buf_end = pgt_buf_start;
        pgt_buf_top = pgt_buf_start + (tables >> PAGE_SHIFT);
-
-       printk(KERN_DEBUG "kernel direct mapping tables up to %#lx @ [mem %#010lx-%#010lx]\n",
-               mr[nr_range - 1].end - 1, pgt_buf_start << PAGE_SHIFT,
-               (pgt_buf_top << PAGE_SHIFT) - 1);
 }
 
 /*
@@ -291,6 +293,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
 
 void __init init_mem_mapping(void)
 {
+       unsigned long tables, good_end, end;
+
        probe_page_size_mask();
 
        /*
@@ -301,10 +305,18 @@ void __init init_mem_mapping(void)
         * nodes are discovered.
         */
 #ifdef CONFIG_X86_64
-       find_early_table_space(0, max_pfn<<PAGE_SHIFT);
+       end = max_pfn << PAGE_SHIFT;
+       good_end = end;
 #else
-       find_early_table_space(0, max_low_pfn<<PAGE_SHIFT);
+       end = max_low_pfn << PAGE_SHIFT;
+       good_end = max_pfn_mapped << PAGE_SHIFT;
 #endif
+       tables = calculate_table_space_size(0, end);
+       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;
 
@@ -331,9 +343,13 @@ void __init init_mem_mapping(void)
         * RO all the pagetable pages, including the ones that are beyond
         * pgt_buf_end at that time.
         */
-       if (pgt_buf_end > pgt_buf_start)
+       if (pgt_buf_end > pgt_buf_start) {
+               printk(KERN_DEBUG "kernel direct mapping tables up to %#lx @ [mem %#010lx-%#010lx] final\n",
+                       end - 1, pgt_buf_start << PAGE_SHIFT,
+                       (pgt_buf_end << PAGE_SHIFT) - 1);
                x86_init.mapping.pagetable_reserve(PFN_PHYS(pgt_buf_start),
                                PFN_PHYS(pgt_buf_end));
+       }
 
        /* stop the wrong using */
        pgt_buf_top = 0;