mm: use vm_unmapped_area() on parisc architecture

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

[akpm@linux-foundation.org: remove now-unused DCACHE_ALIGN(), per James]
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Acked-by: Helge Deller <deller@gmx.de>
Tested-by: Helge Deller <deller@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index 54d619d4cac6107c0df8d7ccd5f111dd5e0486c0..5dfd248e3f1a84fd6dbd961bf278002338cba4b0 100644 (file)
--- a/arch/parisc/kernel/sys_parisc.c
+++ b/arch/parisc/kernel/sys_parisc.c
@@ -35,22 +35,17 @@
 
 static unsigned long get_unshared_area(unsigned long addr, unsigned long len)
 {
-       struct vm_area_struct *vma;
+       struct vm_unmapped_area_info info;
 
-       addr = PAGE_ALIGN(addr);
-
-       for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
-               /* At this point:  (!vma || addr < vma->vm_end). */
-               if (TASK_SIZE - len < addr)
-                       return -ENOMEM;
-               if (!vma || addr + len <= vma->vm_start)
-                       return addr;
-               addr = vma->vm_end;
-       }
+       info.flags = 0;
+       info.length = len;
+       info.low_limit = PAGE_ALIGN(addr);
+       info.high_limit = TASK_SIZE;
+       info.align_mask = 0;
+       info.align_offset = 0;
+       return vm_unmapped_area(&info);
 }
 
-#define DCACHE_ALIGN(addr) (((addr) + (SHMLBA - 1)) &~ (SHMLBA - 1))
-
 /*
  * We need to know the offset to use.  Old scheme was to look for
  * existing mapping and use the same offset.  New scheme is to use the
@@ -63,30 +58,21 @@ static unsigned long get_unshared_area(unsigned long addr, unsigned long len)
  */
 static int get_offset(struct address_space *mapping)
 {
-       int offset = (unsigned long) mapping << (PAGE_SHIFT - 8);
-       return offset & 0x3FF000;
+       return (unsigned long) mapping >> 8;
 }
 
 static unsigned long get_shared_area(struct address_space *mapping,
                unsigned long addr, unsigned long len, unsigned long pgoff)
 {
-       struct vm_area_struct *vma;
-       int offset = mapping ? get_offset(mapping) : 0;
+       struct vm_unmapped_area_info info;
 
-       offset = (offset + (pgoff << PAGE_SHIFT)) & 0x3FF000;
-
-       addr = DCACHE_ALIGN(addr - offset) + offset;
-
-       for (vma = find_vma(current->mm, addr); ; vma = vma->vm_next) {
-               /* At this point:  (!vma || addr < vma->vm_end). */
-               if (TASK_SIZE - len < addr)
-                       return -ENOMEM;
-               if (!vma || addr + len <= vma->vm_start)
-                       return addr;
-               addr = DCACHE_ALIGN(vma->vm_end - offset) + offset;
-               if (addr < vma->vm_end) /* handle wraparound */
-                       return -ENOMEM;
-       }
+       info.flags = 0;
+       info.length = len;
+       info.low_limit = PAGE_ALIGN(addr);
+       info.high_limit = TASK_SIZE;
+       info.align_mask = PAGE_MASK & (SHMLBA - 1);
+       info.align_offset = (get_offset(mapping) + pgoff) << PAGE_SHIFT;
+       return vm_unmapped_area(&info);
 }
 
 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,