x86, mm: Change cachemode exports to non-gpl

[cascardo/linux.git] / arch / x86 / mm / init.c

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index a97ee08..079c3b6 100644 (file)
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -43,7 +43,7 @@ uint16_t __cachemode2pte_tbl[_PAGE_CACHE_MODE_NUM] = {
        [_PAGE_CACHE_MODE_WT]           = _PAGE_PCD,
        [_PAGE_CACHE_MODE_WP]           = _PAGE_PCD,
 };
-EXPORT_SYMBOL_GPL(__cachemode2pte_tbl);
+EXPORT_SYMBOL(__cachemode2pte_tbl);
 uint8_t __pte2cachemode_tbl[8] = {
        [__pte2cm_idx(0)] = _PAGE_CACHE_MODE_WB,
        [__pte2cm_idx(_PAGE_PWT)] = _PAGE_CACHE_MODE_WC,
@@ -54,7 +54,7 @@ uint8_t __pte2cachemode_tbl[8] = {
        [__pte2cm_idx(_PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC_MINUS,
        [__pte2cm_idx(_PAGE_PWT | _PAGE_PCD | _PAGE_PAT)] = _PAGE_CACHE_MODE_UC,
 };
-EXPORT_SYMBOL_GPL(__pte2cachemode_tbl);
+EXPORT_SYMBOL(__pte2cachemode_tbl);
 
 static unsigned long __initdata pgt_buf_start;
 static unsigned long __initdata pgt_buf_end;
@@ -438,20 +438,20 @@ static unsigned long __init init_range_memory_mapping(
 static unsigned long __init get_new_step_size(unsigned long step_size)
 {
        /*
-        * Explain why we shift by 5 and why we don't have to worry about
-        * 'step_size << 5' overflowing:
-        *
-        * initial mapped size is PMD_SIZE (2M).
+        * Initial mapped size is PMD_SIZE (2M).
         * We can not set step_size to be PUD_SIZE (1G) yet.
         * In worse case, when we cross the 1G boundary, and
         * PG_LEVEL_2M is not set, we will need 1+1+512 pages (2M + 8k)
-        * to map 1G range with PTE. Use 5 as shift for now.
+        * to map 1G range with PTE. Hence we use one less than the
+        * difference of page table level shifts.
         *
-        * Don't need to worry about overflow, on 32bit, when step_size
-        * is 0, round_down() returns 0 for start, and that turns it
-        * into 0x100000000ULL.
+        * Don't need to worry about overflow in the top-down case, on 32bit,
+        * when step_size is 0, round_down() returns 0 for start, and that
+        * turns it into 0x100000000ULL.
+        * In the bottom-up case, round_up(x, 0) returns 0 though too, which
+        * needs to be taken into consideration by the code below.
         */
-       return step_size << 5;
+       return step_size << (PMD_SHIFT - PAGE_SHIFT - 1);
 }
 
 /**
@@ -471,7 +471,6 @@ static void __init memory_map_top_down(unsigned long map_start,
        unsigned long step_size;
        unsigned long addr;
        unsigned long mapped_ram_size = 0;
-       unsigned long new_mapped_ram_size;
 
        /* xen has big range in reserved near end of ram, skip it at first.*/
        addr = memblock_find_in_range(map_start, map_end, PMD_SIZE, PMD_SIZE);
@@ -496,14 +495,12 @@ static void __init memory_map_top_down(unsigned long map_start,
                                start = map_start;
                } else
                        start = map_start;
-               new_mapped_ram_size = init_range_memory_mapping(start,
+               mapped_ram_size += init_range_memory_mapping(start,
                                                        last_start);
                last_start = start;
                min_pfn_mapped = last_start >> PAGE_SHIFT;
-               /* only increase step_size after big range get mapped */
-               if (new_mapped_ram_size > mapped_ram_size)
+               if (mapped_ram_size >= step_size)
                        step_size = get_new_step_size(step_size);
-               mapped_ram_size += new_mapped_ram_size;
        }
 
        if (real_end < map_end)
@@ -524,7 +521,7 @@ static void __init memory_map_top_down(unsigned long map_start,
 static void __init memory_map_bottom_up(unsigned long map_start,
                                        unsigned long map_end)
 {
-       unsigned long next, new_mapped_ram_size, start;
+       unsigned long next, start;
        unsigned long mapped_ram_size = 0;
        /* step_size need to be small so pgt_buf from BRK could cover it */
        unsigned long step_size = PMD_SIZE;
@@ -539,19 +536,19 @@ static void __init memory_map_bottom_up(unsigned long map_start,
         * for page table.
         */
        while (start < map_end) {
-               if (map_end - start > step_size) {
+               if (step_size && map_end - start > step_size) {
                        next = round_up(start + 1, step_size);
                        if (next > map_end)
                                next = map_end;
-               } else
+               } else {
                        next = map_end;
+               }
 
-               new_mapped_ram_size = init_range_memory_mapping(start, next);
+               mapped_ram_size += init_range_memory_mapping(start, next);
                start = next;
 
-               if (new_mapped_ram_size > mapped_ram_size)
+               if (mapped_ram_size >= step_size)
                        step_size = get_new_step_size(step_size);
-               mapped_ram_size += new_mapped_ram_size;
        }
 }