mm: use vm_unmapped_area() on sparc32 architecture

Update the sparc32 arch_get_unmapped_area function to make use of
vm_unmapped_area() instead of implementing a brute force search.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: remove now-unused COLOUR_ALIGN()]
Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/sparc/kernel/sys_sparc_32.c

@@ -34,11 +34,9 @@ asmlinkage unsigned long sys_getpagesize(void)
 	return PAGE_SIZE; /* Possibly older binaries want 8192 on sun4's? */
 }
 
-#define COLOUR_ALIGN(addr)      (((addr)+SHMLBA-1)&~(SHMLBA-1))
-
 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags)
 {
-	struct vm_area_struct * vmm;
+	struct vm_unmapped_area_info info;
 
 	if (flags & MAP_FIXED) {
 		/* We do not accept a shared mapping if it would violate
@@ -56,21 +54,14 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	if (!addr)
 		addr = TASK_UNMAPPED_BASE;
 
-	if (flags & MAP_SHARED)
-		addr = COLOUR_ALIGN(addr);
-	else
-		addr = PAGE_ALIGN(addr);
-
-	for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
-		/* At this point:  (!vmm || addr < vmm->vm_end). */
-		if (TASK_SIZE - PAGE_SIZE - len < addr)
-			return -ENOMEM;
-		if (!vmm || addr + len <= vmm->vm_start)
-			return addr;
-		addr = vmm->vm_end;
-		if (flags & MAP_SHARED)
-			addr = COLOUR_ALIGN(addr);
-	}
+	info.flags = 0;
+	info.length = len;
+	info.low_limit = addr;
+	info.high_limit = TASK_SIZE;
+	info.align_mask = (flags & MAP_SHARED) ?
+		(PAGE_MASK & (SHMLBA - 1)) : 0;
+	info.align_offset = pgoff << PAGE_SHIFT;
+	return vm_unmapped_area(&info);
 }
 
 /*