mm: use vm_unmapped_area() on ia64 architecture
authorMichel Lespinasse <walken@google.com>
Thu, 21 Feb 2013 23:10:28 +0000 (15:10 -0800)
committerTony Luck <tony.luck@intel.com>
Fri, 22 Feb 2013 21:46:59 +0000 (13:46 -0800)
Update the ia64 arch_get_unmapped_area function to make use of
vm_unmapped_area() instead of implementing a brute force search.

Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>
arch/ia64/kernel/sys_ia64.c

index d9439ef..41e33f8 100644 (file)
@@ -25,9 +25,9 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
                        unsigned long pgoff, unsigned long flags)
 {
        long map_shared = (flags & MAP_SHARED);
-       unsigned long start_addr, align_mask = PAGE_SIZE - 1;
+       unsigned long align_mask = 0;
        struct mm_struct *mm = current->mm;
-       struct vm_area_struct *vma;
+       struct vm_unmapped_area_info info;
 
        if (len > RGN_MAP_LIMIT)
                return -ENOMEM;
@@ -44,7 +44,7 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
                addr = 0;
 #endif
        if (!addr)
-               addr = mm->free_area_cache;
+               addr = TASK_UNMAPPED_BASE;
 
        if (map_shared && (TASK_SIZE > 0xfffffffful))
                /*
@@ -53,28 +53,15 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
                 * tasks, we prefer to avoid exhausting the address space too quickly by
                 * limiting alignment to a single page.
                 */
-               align_mask = SHMLBA - 1;
-
-  full_search:
-       start_addr = addr = (addr + align_mask) & ~align_mask;
-
-       for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
-               /* At this point:  (!vma || addr < vma->vm_end). */
-               if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
-                       if (start_addr != TASK_UNMAPPED_BASE) {
-                               /* Start a new search --- just in case we missed some holes.  */
-                               addr = TASK_UNMAPPED_BASE;
-                               goto full_search;
-                       }
-                       return -ENOMEM;
-               }
-               if (!vma || addr + len <= vma->vm_start) {
-                       /* Remember the address where we stopped this search:  */
-                       mm->free_area_cache = addr + len;
-                       return addr;
-               }
-               addr = (vma->vm_end + align_mask) & ~align_mask;
-       }
+               align_mask = PAGE_MASK & (SHMLBA - 1);
+
+       info.flags = 0;
+       info.length = len;
+       info.low_limit = addr;
+       info.high_limit = TASK_SIZE;
+       info.align_mask = align_mask;
+       info.align_offset = 0;
+       return vm_unmapped_area(&info);
 }
 
 asmlinkage long