From 5ce704f877057e257ecb9f5cdec6c4aa5c0d064c Mon Sep 17 00:00:00 2001
From: Ralf Baechle <ralf@linux-mips.org>
Date: Wed, 21 Feb 2007 09:37:44 +0000
Subject: [PATCH] Revert "[PATCH] Generic ioremap_page_range: mips conversion"

The generic version truncates addresses.

This reverts commit 8e087929df884dbb13e383d49d192bdd6928ecbf.
---
 arch/mips/mm/ioremap.c | 96 ++++++++++++++++++++++++++++++++++++++----
 1 file changed, 88 insertions(+), 8 deletions(-)

diff --git a/arch/mips/mm/ioremap.c b/arch/mips/mm/ioremap.c
index fc2c96f0a1f..cea7d0ea36e 100644
--- a/arch/mips/mm/ioremap.c
+++ b/arch/mips/mm/ioremap.c
@@ -6,13 +6,98 @@
  * (C) Copyright 1995 1996 Linus Torvalds
  * (C) Copyright 2001, 2002 Ralf Baechle
  */
-#include <linux/mm.h>
 #include <linux/module.h>
 #include <asm/addrspace.h>
 #include <asm/byteorder.h>
 
 #include <linux/vmalloc.h>
-#include <linux/io.h>
+#include <asm/cacheflush.h>
+#include <asm/io.h>
+#include <asm/tlbflush.h>
+
+static inline void remap_area_pte(pte_t * pte, unsigned long address,
+	phys_t size, phys_t phys_addr, unsigned long flags)
+{
+	phys_t end;
+	unsigned long pfn;
+	pgprot_t pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | __READABLE
+	                           | __WRITEABLE | flags);
+
+	address &= ~PMD_MASK;
+	end = address + size;
+	if (end > PMD_SIZE)
+		end = PMD_SIZE;
+	if (address >= end)
+		BUG();
+	pfn = phys_addr >> PAGE_SHIFT;
+	do {
+		if (!pte_none(*pte)) {
+			printk("remap_area_pte: page already exists\n");
+			BUG();
+		}
+		set_pte(pte, pfn_pte(pfn, pgprot));
+		address += PAGE_SIZE;
+		pfn++;
+		pte++;
+	} while (address && (address < end));
+}
+
+static inline int remap_area_pmd(pmd_t * pmd, unsigned long address,
+	phys_t size, phys_t phys_addr, unsigned long flags)
+{
+	phys_t end;
+
+	address &= ~PGDIR_MASK;
+	end = address + size;
+	if (end > PGDIR_SIZE)
+		end = PGDIR_SIZE;
+	phys_addr -= address;
+	if (address >= end)
+		BUG();
+	do {
+		pte_t * pte = pte_alloc_kernel(pmd, address);
+		if (!pte)
+			return -ENOMEM;
+		remap_area_pte(pte, address, end - address, address + phys_addr, flags);
+		address = (address + PMD_SIZE) & PMD_MASK;
+		pmd++;
+	} while (address && (address < end));
+	return 0;
+}
+
+static int remap_area_pages(unsigned long address, phys_t phys_addr,
+	phys_t size, unsigned long flags)
+{
+	int error;
+	pgd_t * dir;
+	unsigned long end = address + size;
+
+	phys_addr -= address;
+	dir = pgd_offset(&init_mm, address);
+	flush_cache_all();
+	if (address >= end)
+		BUG();
+	do {
+		pud_t *pud;
+		pmd_t *pmd;
+
+		error = -ENOMEM;
+		pud = pud_alloc(&init_mm, dir, address);
+		if (!pud)
+			break;
+		pmd = pmd_alloc(&init_mm, pud, address);
+		if (!pmd)
+			break;
+		if (remap_area_pmd(pmd, address, end - address,
+					 phys_addr + address, flags))
+			break;
+		error = 0;
+		address = (address + PGDIR_SIZE) & PGDIR_MASK;
+		dir++;
+	} while (address && (address < end));
+	flush_tlb_all();
+	return error;
+}
 
 /*
  * Generic mapping function (not visible outside):
@@ -36,7 +121,6 @@ void __iomem * __ioremap(phys_t phys_addr, phys_t size, unsigned long flags)
 	unsigned long offset;
 	phys_t last_addr;
 	void * addr;
-	pgprot_t pgprot;
 
 	phys_addr = fixup_bigphys_addr(phys_addr, size);
 
@@ -68,9 +152,6 @@ void __iomem * __ioremap(phys_t phys_addr, phys_t size, unsigned long flags)
 				return NULL;
 	}
 
-	pgprot = __pgprot(_PAGE_GLOBAL | _PAGE_PRESENT | __READABLE
-			  | __WRITEABLE | flags);
-
 	/*
 	 * Mappings have to be page-aligned
 	 */
@@ -85,8 +166,7 @@ void __iomem * __ioremap(phys_t phys_addr, phys_t size, unsigned long flags)
 	if (!area)
 		return NULL;
 	addr = area->addr;
-	if (ioremap_page_range((unsigned long)addr, (unsigned long)addr + size,
-			       phys_addr, pgprot)) {
+	if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
 		vunmap(addr);
 		return NULL;
 	}
-- 
2.20.1