x86: i386: reduce boot fixmap space

As 256 entries are needed, aligning to a 256-entry boundary is
sufficient and still guarantees the single pte table requirement.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

diff --git a/include/asm-x86/fixmap_32.h b/include/asm-x86/fixmap_32.h
index aae2f05..f1ac2b2 100644 (file)
--- a/include/asm-x86/fixmap_32.h
+++ b/include/asm-x86/fixmap_32.h
@@ -90,13 +90,13 @@ enum fixed_addresses {
         * 256 temporary boot-time mappings, used by early_ioremap(),
         * before ioremap() is functional.
         *
-        * We round it up to the next 512 pages boundary so that we
+        * We round it up to the next 256 pages boundary so that we
         * can have a single pgd entry and a single pte table:
         */
 #define NR_FIX_BTMAPS          64
 #define FIX_BTMAPS_NESTING     4
-       FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 512 -
-                       (__end_of_permanent_fixed_addresses & 511),
+       FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -
+                       (__end_of_permanent_fixed_addresses & 255),
        FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_NESTING - 1,
        FIX_WP_TEST,
 #ifdef CONFIG_ACPI