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, 1 insertions, 2 deletions

diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index 8396868e82c5..c483f4242079 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -334,7 +334,6 @@ int devmem_is_allowed(unsigned long pagenr)
         return 0;
 }
 
-#ifdef CONFIG_HIGHMEM
 pte_t *kmap_pte;
 pgprot_t kmap_prot;
 
@@ -357,6 +356,7 @@ static void __init kmap_init(void)
         kmap_prot = PAGE_KERNEL;
 }
 
+#ifdef CONFIG_HIGHMEM
 static void __init permanent_kmaps_init(pgd_t *pgd_base)
 {
         unsigned long vaddr;
@@ -436,7 +436,6 @@ static void __init set_highmem_pages_init(void)
 #endif /* !CONFIG_NUMA */
 
 #else
-# define kmap_init()                            do { } while (0)
 # define permanent_kmaps_init(pgd_base)         do { } while (0)
 # define set_highmem_pages_init()       do { } while (0)
 #endif /* CONFIG_HIGHMEM */