[PATCH v4] Revert fixrange_init() limiting to the FIXMAP region.

["Steven J. Hill" <sjhill@mips.com>]

From: "Steven J. Hill" <sjhill@mips.com>

This patch refactors commit 464fd83e841a16f4ea1325b33eb08170ef5cd1f4
(MIPS: Limit fixrange_init() to the FIXMAP region) and correctly
calculates the right length while taking into account page table
alignment by PMD.

Signed-off-by: Leonid Yegoshin <yegoshin@mips.com>
Signed-off-by: Steven J. Hill <sjhill@mips.com>
---
 arch/mips/mm/init.c       |    6 +++---
 arch/mips/mm/pgtable-32.c |    8 ++++++--
 arch/mips/mm/pgtable-64.c |    2 +-
 3 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
index 1a85ba9..75f2724 100644
--- a/arch/mips/mm/init.c
+++ b/arch/mips/mm/init.c
@@ -277,11 +277,11 @@ void __init fixrange_init(unsigned long start, unsigned 
long end,
        k = __pmd_offset(vaddr);
        pgd = pgd_base + i;
 
-       for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
+       for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
                pud = (pud_t *)pgd;
-               for ( ; (j < PTRS_PER_PUD) && (vaddr < end); pud++, j++) {
+               for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
                        pmd = (pmd_t *)pud;
-                       for (; (k < PTRS_PER_PMD) && (vaddr < end); pmd++, k++) 
{
+                       for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, 
k++) {
                                if (pmd_none(*pmd)) {
                                        pte = (pte_t *) 
alloc_bootmem_low_pages(PAGE_SIZE);
                                        set_pmd(pmd, __pmd((unsigned long)pte));
diff --git a/arch/mips/mm/pgtable-32.c b/arch/mips/mm/pgtable-32.c
index adc6911..5d27baf 100644
--- a/arch/mips/mm/pgtable-32.c
+++ b/arch/mips/mm/pgtable-32.c
@@ -33,6 +33,7 @@ void pgd_init(unsigned long page)
 void __init pagetable_init(void)
 {
        unsigned long vaddr;
+       unsigned long vend;
        pgd_t *pgd_base;
 #ifdef CONFIG_HIGHMEM
        pgd_t *pgd;
@@ -51,8 +52,11 @@ void __init pagetable_init(void)
        /*
         * Fixed mappings:
         */
-       vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
-       fixrange_init(vaddr, vaddr + FIXADDR_SIZE, pgd_base);
+       vaddr = __fix_to_virt(__end_of_fixed_addresses - 1);
+       /* Calculate real end before alignment. */
+       vend = vaddr + FIXADDR_SIZE;
+       vaddr = vaddr & PMD_MASK;
+       fixrange_init(vaddr, vend, pgd_base);
 
 #ifdef CONFIG_HIGHMEM
        /*
diff --git a/arch/mips/mm/pgtable-64.c b/arch/mips/mm/pgtable-64.c
index cda4e30..78eaa4f 100644
--- a/arch/mips/mm/pgtable-64.c
+++ b/arch/mips/mm/pgtable-64.c
@@ -76,5 +76,5 @@ void __init pagetable_init(void)
         * Fixed mappings:
         */
        vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
-       fixrange_init(vaddr, vaddr + FIXADDR_SIZE, pgd_base);
+       fixrange_init(vaddr, 0, pgd_base);
 }
-- 
1.7.10