x86: add iomap_atomic*()/iounmap_atomic() on 32-bit using fixmaps

Impact: introduce new APIs, separate kmap code from CONFIG_HIGHMEM

This takes the code used for CONFIG_HIGHMEM memory mappings except that
it's designed for dynamic IO resource mapping.

These fixmaps are available even with CONFIG_HIGHMEM turned off.

Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h
index 8668a94f850e..23696d44a0af 100644
--- a/arch/x86/include/asm/fixmap.h
+++ b/arch/x86/include/asm/fixmap.h
@@ -9,6 +9,10 @@
 
 extern int fixmaps_set;
 
+extern pte_t *kmap_pte;
+extern pgprot_t kmap_prot;
+extern pte_t *pkmap_page_table;
+
 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);
 void native_set_fixmap(enum fixed_addresses idx,
                        unsigned long phys, pgprot_t flags);