X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fx86_64%2Fmm%2Fioremap.c;h=ae207064201e19697160a332a3399f9a0594b2f8;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=bae79b818d85108b5cc674c28303afb92438fdb4;hpb=8e8ece46a861c84343256819eaec77e608ff9217;p=linux-2.6.git

diff --git a/arch/x86_64/mm/ioremap.c b/arch/x86_64/mm/ioremap.c
index bae79b818..ae2070642 100644
--- a/arch/x86_64/mm/ioremap.c
+++ b/arch/x86_64/mm/ioremap.c
@@ -18,6 +18,9 @@
 #include <asm/tlbflush.h>
 #include <asm/proto.h>
 
+#define ISA_START_ADDRESS      0xa0000
+#define ISA_END_ADDRESS                0x100000
+
 static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
 	unsigned long phys_addr, unsigned long flags)
 {
@@ -57,7 +60,7 @@ static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned lo
 	if (address >= end)
 		BUG();
 	do {
-		pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+		pte_t * pte = pte_alloc_kernel(pmd, address);
 		if (!pte)
 			return -ENOMEM;
 		remap_area_pte(pte, address, end - address, address + phys_addr, flags);
@@ -102,7 +105,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
 	flush_cache_all();
 	if (address >= end)
 		BUG();
-	spin_lock(&init_mm.page_table_lock);
 	do {
 		pud_t *pud;
 		pud = pud_alloc(&init_mm, pgd, address);
@@ -116,7 +118,6 @@ static int remap_area_pages(unsigned long address, unsigned long phys_addr,
 		address = (address + PGDIR_SIZE) & PGDIR_MASK;
 		pgd++;
 	} while (address && (address < end));
-	spin_unlock(&init_mm.page_table_lock);
 	flush_tlb_all();
 	return error;
 }
@@ -130,7 +131,7 @@ ioremap_change_attr(unsigned long phys_addr, unsigned long size,
 					unsigned long flags)
 {
 	int err = 0;
-	if (flags && phys_addr + size - 1 < (end_pfn_map << PAGE_SHIFT)) {
+	if (phys_addr + size - 1 < (end_pfn_map << PAGE_SHIFT)) {
 		unsigned long npages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 		unsigned long vaddr = (unsigned long) __va(phys_addr);
 
@@ -172,10 +173,10 @@ void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned l
 	/*
 	 * Don't remap the low PCI/ISA area, it's always mapped..
 	 */
-	if (phys_addr >= 0xA0000 && last_addr < 0x100000)
+	if (phys_addr >= ISA_START_ADDRESS && last_addr < ISA_END_ADDRESS)
 		return (__force void __iomem *)phys_to_virt(phys_addr);
 
-#ifndef CONFIG_DISCONTIGMEM
+#ifdef CONFIG_FLATMEM
 	/*
 	 * Don't allow anybody to remap normal RAM that we're using..
 	 */
@@ -211,7 +212,7 @@ void __iomem * __ioremap(unsigned long phys_addr, unsigned long size, unsigned l
 		remove_vm_area((void *)(PAGE_MASK & (unsigned long) addr));
 		return NULL;
 	}
-	if (ioremap_change_attr(phys_addr, size, flags) < 0) {
+	if (flags && ioremap_change_attr(phys_addr, size, flags) < 0) {
 		area->flags &= 0xffffff;
 		vunmap(addr);
 		return NULL;
@@ -246,32 +247,47 @@ void __iomem *ioremap_nocache (unsigned long phys_addr, unsigned long size)
 	return __ioremap(phys_addr, size, _PAGE_PCD);
 }
 
+/**
+ * iounmap - Free a IO remapping
+ * @addr: virtual address from ioremap_*
+ *
+ * Caller must ensure there is only one unmapping for the same pointer.
+ */
 void iounmap(volatile void __iomem *addr)
 {
-	struct vm_struct *p, **pprev;
+	struct vm_struct *p, *o;
 
 	if (addr <= high_memory) 
 		return; 
+	if (addr >= phys_to_virt(ISA_START_ADDRESS) &&
+		addr < phys_to_virt(ISA_END_ADDRESS))
+		return;
 
-	write_lock(&vmlist_lock);
-	for (p = vmlist, pprev = &vmlist; p != NULL; pprev = &p->next, p = *pprev)
-		if (p->addr == (void *)(PAGE_MASK & (unsigned long)addr))
+	addr = (volatile void __iomem *)(PAGE_MASK & (unsigned long __force)addr);
+	/* Use the vm area unlocked, assuming the caller
+	   ensures there isn't another iounmap for the same address
+	   in parallel. Reuse of the virtual address is prevented by
+	   leaving it in the global lists until we're done with it.
+	   cpa takes care of the direct mappings. */
+	read_lock(&vmlist_lock);
+	for (p = vmlist; p; p = p->next) {
+		if (p->addr == addr)
 			break;
-	if (!p) { 
-		printk("__iounmap: bad address %p\n", addr);
-		goto out_unlock;
 	}
-	*pprev = p->next;
-	unmap_vm_area(p);
-	if ((p->flags >> 20) &&
-		p->phys_addr + p->size - 1 < virt_to_phys(high_memory)) {
-		/* p->size includes the guard page, but cpa doesn't like that */
-		change_page_attr_addr((unsigned long)(__va(p->phys_addr)),
-				 (p->size - PAGE_SIZE) >> PAGE_SHIFT,
-				 PAGE_KERNEL); 				 
-		global_flush_tlb();
-	} 
-out_unlock:
-	write_unlock(&vmlist_lock);
+	read_unlock(&vmlist_lock);
+
+	if (!p) {
+		printk("iounmap: bad address %p\n", addr);
+		dump_stack();
+		return;
+	}
+
+	/* Reset the direct mapping. Can block */
+	if (p->flags >> 20)
+		ioremap_change_attr(p->phys_addr, p->size, 0);
+
+	/* Finally remove it */
+	o = remove_vm_area((void *)addr);
+	BUG_ON(p != o || o == NULL);
 	kfree(p); 
 }