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

["Steven J. Hill" <sjhill@xxxxxxxx>]

From: "Steven J. Hill" <sjhill@xxxxxxxx>

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@xxxxxxxx>
Signed-off-by: Steven J. Hill <sjhill@xxxxxxxx>
---
 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