mm: use vm_unmapped_area() on ia64 architecture

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>

1 files changed, 12 insertions, 25 deletions

diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
index d9439ef2f661..41e33f84c185 100644
--- a/arch/ia64/kernel/sys_ia64.c
+++ b/arch/ia64/kernel/sys_ia64.c
@@ -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