[ARM] fix section-based ioremap

Tomi Valkeinen reports:
  Running with latest linux-omap kernel on OMAP3 SDP board, I have
  problem with iounmap(). It looks like iounmap() does not properly
  free large areas. Below is a test which fails for me in 6-7 loops.

	for (i = 0; i < 200; ++i) {
		vaddr = ioremap(paddr, size);
		if (!vaddr) {
			printk("couldn't ioremap\n");
			break;
		}
		iounmap(vaddr);
	}

The changes to vmalloc.c weren't reflected in the ARM ioremap
implementation.  Turns out the fix is rather simple.

Tested-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Tested-by: Matt Gerassimoff <mgeras@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 2 insertions, 9 deletions

diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 18373f73f2fc..9f88dd3be601 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -138,7 +138,7 @@ void __check_kvm_seq(struct mm_struct *mm)
  */
 static void unmap_area_sections(unsigned long virt, unsigned long size)
 {
-        unsigned long addr = virt, end = virt + (size & ~SZ_1M);
+        unsigned long addr = virt, end = virt + (size & ~(SZ_1M - 1));
         pgd_t *pgd;
 
         flush_cache_vunmap(addr, end);
@@ -337,10 +337,7 @@ void __iounmap(volatile void __iomem *io_addr)
         void *addr = (void *)(PAGE_MASK & (unsigned long)io_addr);
 #ifndef CONFIG_SMP
         struct vm_struct **p, *tmp;
-#endif
-        unsigned int section_mapping = 0;
 
-#ifndef CONFIG_SMP
         /*
          * If this is a section based mapping we need to handle it
          * specially as the VM subsystem does not know how to handle
@@ -352,11 +349,8 @@ void __iounmap(volatile void __iomem *io_addr)
         for (p = &vmlist ; (tmp = *p) ; p = &tmp->next) {
                 if ((tmp->flags & VM_IOREMAP) && (tmp->addr == addr)) {
                         if (tmp->flags & VM_ARM_SECTION_MAPPING) {
-                                *p = tmp->next;
                                 unmap_area_sections((unsigned long)tmp->addr,
                                                     tmp->size);
-                                kfree(tmp);
-                                section_mapping = 1;
                         }
                         break;
                 }
@@ -364,7 +358,6 @@ void __iounmap(volatile void __iomem *io_addr)
         write_unlock(&vmlist_lock);
 #endif
 
-        if (!section_mapping)
-                vunmap(addr);
+        vunmap(addr);
 }
 EXPORT_SYMBOL(__iounmap);