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authorRussell King <rmk+kernel@arm.linux.org.uk>2014-11-03 11:12:13 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2014-11-03 11:12:13 +0100
commit06e944b8e5fc4bec83f102f98c1ee4f972f5f072 (patch)
treed53b1c3ca270f49f1cae63bbe117cc8587e51510 /arch/arm/mm/mmu.c
parentLinux 3.18-rc1 (diff)
parentARM: mm: allow text and rodata sections to be read-only (diff)
downloadlinux-06e944b8e5fc4bec83f102f98c1ee4f972f5f072.tar.xz
linux-06e944b8e5fc4bec83f102f98c1ee4f972f5f072.zip
Merge tag 'ronx-next' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux into devel-stable
generic fixmaps ARM support for CONFIG_DEBUG_RODATA
Diffstat (limited to 'arch/arm/mm/mmu.c')
-rw-r--r--arch/arm/mm/mmu.c39
1 files changed, 35 insertions, 4 deletions
diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 9f98cec7fe1e..a7b12cb21e81 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -22,6 +22,7 @@
#include <asm/cputype.h>
#include <asm/sections.h>
#include <asm/cachetype.h>
+#include <asm/fixmap.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/smp_plat.h>
@@ -393,6 +394,29 @@ SET_MEMORY_FN(x, pte_set_x)
SET_MEMORY_FN(nx, pte_set_nx)
/*
+ * To avoid TLB flush broadcasts, this uses local_flush_tlb_kernel_range().
+ * As a result, this can only be called with preemption disabled, as under
+ * stop_machine().
+ */
+void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
+{
+ unsigned long vaddr = __fix_to_virt(idx);
+ pte_t *pte = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
+
+ /* Make sure fixmap region does not exceed available allocation. */
+ BUILD_BUG_ON(FIXADDR_START + (__end_of_fixed_addresses * PAGE_SIZE) >
+ FIXADDR_END);
+ BUG_ON(idx >= __end_of_fixed_addresses);
+
+ if (pgprot_val(prot))
+ set_pte_at(NULL, vaddr, pte,
+ pfn_pte(phys >> PAGE_SHIFT, prot));
+ else
+ pte_clear(NULL, vaddr, pte);
+ local_flush_tlb_kernel_range(vaddr, vaddr + PAGE_SIZE);
+}
+
+/*
* Adjust the PMD section entries according to the CPU in use.
*/
static void __init build_mem_type_table(void)
@@ -1326,10 +1350,10 @@ static void __init kmap_init(void)
#ifdef CONFIG_HIGHMEM
pkmap_page_table = early_pte_alloc(pmd_off_k(PKMAP_BASE),
PKMAP_BASE, _PAGE_KERNEL_TABLE);
-
- fixmap_page_table = early_pte_alloc(pmd_off_k(FIXADDR_START),
- FIXADDR_START, _PAGE_KERNEL_TABLE);
#endif
+
+ early_pte_alloc(pmd_off_k(FIXADDR_START), FIXADDR_START,
+ _PAGE_KERNEL_TABLE);
}
static void __init map_lowmem(void)
@@ -1349,13 +1373,20 @@ static void __init map_lowmem(void)
if (start >= end)
break;
- if (end < kernel_x_start || start >= kernel_x_end) {
+ if (end < kernel_x_start) {
map.pfn = __phys_to_pfn(start);
map.virtual = __phys_to_virt(start);
map.length = end - start;
map.type = MT_MEMORY_RWX;
create_mapping(&map);
+ } else if (start >= kernel_x_end) {
+ map.pfn = __phys_to_pfn(start);
+ map.virtual = __phys_to_virt(start);
+ map.length = end - start;
+ map.type = MT_MEMORY_RW;
+
+ create_mapping(&map);
} else {
/* This better cover the entire kernel */
if (start < kernel_x_start) {