shmem: get_unmapped_area align huge page

[linux-2.6-microblaze.git] / mm / mmap.c

diff --git a/mm/mmap.c b/mm/mmap.c
index a41872c..86b18f3 100644 (file)
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -25,6 +25,7 @@
 #include <linux/personality.h>
 #include <linux/security.h>
 #include <linux/hugetlb.h>
+#include <linux/shmem_fs.h>
 #include <linux/profile.h>
 #include <linux/export.h>
 #include <linux/mount.h>
@@ -1897,8 +1898,19 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
                return -ENOMEM;
 
        get_area = current->mm->get_unmapped_area;
-       if (file && file->f_op->get_unmapped_area)
-               get_area = file->f_op->get_unmapped_area;
+       if (file) {
+               if (file->f_op->get_unmapped_area)
+                       get_area = file->f_op->get_unmapped_area;
+       } else if (flags & MAP_SHARED) {
+               /*
+                * mmap_region() will call shmem_zero_setup() to create a file,
+                * so use shmem's get_unmapped_area in case it can be huge.
+                * do_mmap_pgoff() will clear pgoff, so match alignment.
+                */
+               pgoff = 0;
+               get_area = shmem_get_unmapped_area;
+       }
+
        addr = get_area(file, addr, len, pgoff, flags);
        if (IS_ERR_VALUE(addr))
                return addr;