x86: fix init_memory_mapping over boundary, v4

use PMD_SHIFT to calculate boundary also adjust size for pre-allocated
table size

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 90ca67b..aa5e37c 100644 (file)
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -184,8 +184,9 @@ static inline int is_kernel_text(unsigned long addr)
  * PAGE_OFFSET:
  */
 static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
-                                               unsigned long start,
-                                               unsigned long end)
+                                               unsigned long start_pfn,
+                                               unsigned long end_pfn,
+                                               int use_pse)
 {
        int pgd_idx, pmd_idx, pte_ofs;
        unsigned long pfn;
@@ -193,33 +194,33 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
        pmd_t *pmd;
        pte_t *pte;
        unsigned pages_2m = 0, pages_4k = 0;
-       unsigned limit_pfn = end >> PAGE_SHIFT;
 
-       pgd_idx = pgd_index(start + PAGE_OFFSET);
-       pgd = pgd_base + pgd_idx;
-       pfn = start >> PAGE_SHIFT;
+       if (!cpu_has_pse)
+               use_pse = 0;
 
+       pfn = start_pfn;
+       pgd_idx = pgd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
+       pgd = pgd_base + pgd_idx;
        for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) {
                pmd = one_md_table_init(pgd);
-               if (pfn >= limit_pfn)
-                       continue;
 
-               for (pmd_idx = 0;
-                    pmd_idx < PTRS_PER_PMD && pfn < limit_pfn;
+               if (pfn >= end_pfn)
+                       continue;
+#ifdef CONFIG_X86_PAE
+               pmd_idx = pmd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
+               pmd += pmd_idx;
+#else
+               pmd_idx = 0;
+#endif
+               for (; pmd_idx < PTRS_PER_PMD && pfn < end_pfn;
                     pmd++, pmd_idx++) {
                        unsigned int addr = pfn * PAGE_SIZE + PAGE_OFFSET;
 
                        /*
                         * Map with big pages if possible, otherwise
                         * create normal page tables:
-                        *
-                        * Don't use a large page for the first 2/4MB of memory
-                        * because there are often fixed size MTRRs in there
-                        * and overlapping MTRRs into large pages can cause
-                        * slowdowns.
                         */
-                       if (cpu_has_pse && !(pgd_idx == 0 && pmd_idx == 0) &&
-                               (pfn + PTRS_PER_PTE) <= limit_pfn) {
+                       if (use_pse) {
                                unsigned int addr2;
                                pgprot_t prot = PAGE_KERNEL_LARGE;
 
@@ -238,8 +239,9 @@ static void __init kernel_physical_mapping_init(pgd_t *pgd_base,
                        }
                        pte = one_page_table_init(pmd);
 
-                       for (pte_ofs = 0;
-                            pte_ofs < PTRS_PER_PTE && pfn < limit_pfn;
+                       pte_ofs = pte_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
+                       pte += pte_ofs;
+                       for (; pte_ofs < PTRS_PER_PTE && pfn < end_pfn;
                             pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) {
                                pgprot_t prot = PAGE_KERNEL;
 
@@ -738,14 +740,18 @@ static void __init find_early_table_space(unsigned long end)
 
        if (cpu_has_pse) {
                unsigned long extra;
-               extra = end - ((end>>21) << 21);
-               extra += (2UL<<20);
+
+               extra = end - ((end>>PMD_SHIFT) << PMD_SHIFT);
+               extra += PMD_SIZE;
                ptes = (extra + PAGE_SIZE - 1) >> PAGE_SHIFT;
        } else
                ptes = (end + PAGE_SIZE - 1) >> PAGE_SHIFT;
 
        tables += PAGE_ALIGN(ptes * sizeof(pte_t));
 
+       /* for fixmap */
+       tables += PAGE_SIZE * 2;
+
        /*
         * RED-PEN putting page tables only on node 0 could
         * cause a hotspot and fill up ZONE_DMA. The page tables
@@ -770,6 +776,8 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
                                                unsigned long end)
 {
        pgd_t *pgd_base = swapper_pg_dir;
+       unsigned long start_pfn, end_pfn;
+       unsigned long big_page_start;
 
        /*
         * Find space for the kernel direct mapping tables.
@@ -794,7 +802,44 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
                __PAGE_KERNEL_EXEC |= _PAGE_GLOBAL;
        }
 
-       kernel_physical_mapping_init(pgd_base, start, end);
+       /*
+        * Don't use a large page for the first 2/4MB of memory
+        * because there are often fixed size MTRRs in there
+        * and overlapping MTRRs into large pages can cause
+        * slowdowns.
+        */
+       big_page_start = PMD_SIZE;
+
+       if (start < big_page_start) {
+               start_pfn = start >> PAGE_SHIFT;
+               end_pfn = min(big_page_start>>PAGE_SHIFT, end>>PAGE_SHIFT);
+       } else {
+               /* head is not big page alignment ? */
+               start_pfn = start >> PAGE_SHIFT;
+               end_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
+                                << (PMD_SHIFT - PAGE_SHIFT);
+       }
+       if (start_pfn < end_pfn)
+               kernel_physical_mapping_init(pgd_base, start_pfn, end_pfn, 0);
+
+       /* big page range */
+       start_pfn = ((start + (PMD_SIZE - 1))>>PMD_SHIFT)
+                        << (PMD_SHIFT - PAGE_SHIFT);
+       if (start_pfn < (big_page_start >> PAGE_SHIFT))
+               start_pfn =  big_page_start >> PAGE_SHIFT;
+       end_pfn = (end>>PMD_SHIFT) << (PMD_SHIFT - PAGE_SHIFT);
+       if (start_pfn < end_pfn)
+               kernel_physical_mapping_init(pgd_base, start_pfn, end_pfn,
+                                               cpu_has_pse);
+
+       /* tail is not big page alignment ? */
+       start_pfn = end_pfn;
+       if (start_pfn > (big_page_start>>PAGE_SHIFT)) {
+               end_pfn = end >> PAGE_SHIFT;
+               if (start_pfn < end_pfn)
+                       kernel_physical_mapping_init(pgd_base, start_pfn,
+                                                        end_pfn, 0);
+       }
 
        early_ioremap_page_table_range_init(pgd_base);