[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>

diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 18373f73f2fc4a65c460db459cd061beea9c55b0..9f88dd3be6019ec850e4d5a789ceaf623bb91a92 100644 (file)
--- 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);