1 files changed, 21 insertions, 29 deletions

diff --git a/mm/nommu.c b/mm/nommu.c
index 56a446f05971..9876fa0c3ad3 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -79,7 +79,7 @@ static struct kmem_cache *vm_region_jar;
 struct rb_root nommu_region_tree = RB_ROOT;
 DECLARE_RWSEM(nommu_region_sem);
 
-struct vm_operations_struct generic_file_vm_ops = {
+const struct vm_operations_struct generic_file_vm_ops = {
 };
 
 /*
@@ -826,7 +826,7 @@ static int validate_mmap_request(struct file *file,
         int ret;
 
         /* do the simple checks first */
-        if (flags & MAP_FIXED || addr) {
+        if (flags & MAP_FIXED) {
                 printk(KERN_DEBUG
                        "%d: Can't do fixed-address/overlay mmap of RAM\n",
                        current->pid);
@@ -1034,7 +1034,7 @@ static int do_mmap_shared_file(struct vm_area_struct *vma)
         ret = vma->vm_file->f_op->mmap(vma->vm_file, vma);
         if (ret == 0) {
                 vma->vm_region->vm_top = vma->vm_region->vm_end;
-                return ret;
+                return 0;
         }
         if (ret != -ENOSYS)
                 return ret;
@@ -1051,7 +1051,8 @@ static int do_mmap_shared_file(struct vm_area_struct *vma)
  */
 static int do_mmap_private(struct vm_area_struct *vma,
                            struct vm_region *region,
-                           unsigned long len)
+                           unsigned long len,
+                           unsigned long capabilities)
 {
         struct page *pages;
         unsigned long total, point, n, rlen;
@@ -1062,13 +1063,13 @@ static int do_mmap_private(struct vm_area_struct *vma,
          * shared mappings on devices or memory
          * - VM_MAYSHARE will be set if it may attempt to share
          */
-        if (vma->vm_file) {
+        if (capabilities & BDI_CAP_MAP_DIRECT) {
                 ret = vma->vm_file->f_op->mmap(vma->vm_file, vma);
                 if (ret == 0) {
                         /* shouldn't return success if we're not sharing */
                         BUG_ON(!(vma->vm_flags & VM_MAYSHARE));
                         vma->vm_region->vm_top = vma->vm_region->vm_end;
-                        return ret;
+                        return 0;
                 }
                 if (ret != -ENOSYS)
                         return ret;
@@ -1181,9 +1182,6 @@ unsigned long do_mmap_pgoff(struct file *file,
 
         kenter(",%lx,%lx,%lx,%lx,%lx", addr, len, prot, flags, pgoff);
 
-        if (!(flags & MAP_FIXED))
-                addr = round_hint_to_min(addr);
-
         /* decide whether we should attempt the mapping, and if so what sort of
          * mapping */
         ret = validate_mmap_request(file, addr, len, prot, flags, pgoff,
@@ -1193,6 +1191,9 @@ unsigned long do_mmap_pgoff(struct file *file,
                 return ret;
         }
 
+        /* we ignore the address hint */
+        addr = 0;
+
         /* we've determined that we can make the mapping, now translate what we
          * now know into VMA flags */
         vm_flags = determine_vm_flags(file, prot, flags, capabilities);
@@ -1306,7 +1307,7 @@ unsigned long do_mmap_pgoff(struct file *file,
                  * - this is the hook for quasi-memory character devices to
                  *   tell us the location of a shared mapping
                  */
-                if (file && file->f_op->get_unmapped_area) {
+                if (capabilities & BDI_CAP_MAP_DIRECT) {
                         addr = file->f_op->get_unmapped_area(file, addr, len,
                                                              pgoff, flags);
                         if (IS_ERR((void *) addr)) {
@@ -1330,15 +1331,17 @@ unsigned long do_mmap_pgoff(struct file *file,
         }
 
         vma->vm_region = region;
-        add_nommu_region(region);
 
-        /* set up the mapping */
+        /* set up the mapping
+         * - the region is filled in if BDI_CAP_MAP_DIRECT is still set
+         */
         if (file && vma->vm_flags & VM_SHARED)
                 ret = do_mmap_shared_file(vma);
         else
-                ret = do_mmap_private(vma, region, len);
+                ret = do_mmap_private(vma, region, len, capabilities);
         if (ret < 0)
-                goto error_put_region;
+                goto error_just_free;
+        add_nommu_region(region);
 
         /* okay... we have a mapping; now we have to register it */
         result = vma->vm_start;
@@ -1356,25 +1359,14 @@ share:
         kleave(" = %lx", result);
         return result;
 
-error_put_region:
-        __put_nommu_region(region);
-        if (vma) {
-                if (vma->vm_file) {
-                        fput(vma->vm_file);
-                        if (vma->vm_flags & VM_EXECUTABLE)
-                                removed_exe_file_vma(vma->vm_mm);
-                }
-                kmem_cache_free(vm_area_cachep, vma);
-        }
-        kleave(" = %d [pr]", ret);
-        return ret;
-
 error_just_free:
         up_write(&nommu_region_sem);
 error:
-        fput(region->vm_file);
+        if (region->vm_file)
+                fput(region->vm_file);
         kmem_cache_free(vm_region_jar, region);
-        fput(vma->vm_file);
+        if (vma->vm_file)
+                fput(vma->vm_file);
         if (vma->vm_flags & VM_EXECUTABLE)
                 removed_exe_file_vma(vma->vm_mm);
         kmem_cache_free(vm_area_cachep, vma);