X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=mm%2Fshmem.c;h=79997e8cf807c54b8a8217df6f9b70ef9f4e981f;hb=a1d20be406a7ea5bc226eaa5c866b2e6c95fcd01;hp=80297712314eea49ababd3b59274f5784b5cb73e;hpb=1d3255b4d9f8c592df8e0cfac8078e5148510887;p=firefly-linux-kernel-4.4.55.git

diff --git a/mm/shmem.c b/mm/shmem.c
index 80297712314e..79997e8cf807 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2153,9 +2153,11 @@ static long shmem_fallocate(struct file *file, int mode, loff_t offset,
 									NULL);
 		if (error) {
 			/* Remove the !PageUptodate pages we added */
-			shmem_undo_range(inode,
-				(loff_t)start << PAGE_CACHE_SHIFT,
-				((loff_t)index << PAGE_CACHE_SHIFT) - 1, true);
+			if (index > start) {
+				shmem_undo_range(inode,
+				 (loff_t)start << PAGE_CACHE_SHIFT,
+				 ((loff_t)index << PAGE_CACHE_SHIFT) - 1, true);
+			}
 			goto undone;
 		}
 
@@ -3403,6 +3405,14 @@ struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags
 }
 EXPORT_SYMBOL_GPL(shmem_file_setup);
 
+void shmem_set_file(struct vm_area_struct *vma, struct file *file)
+{
+	if (vma->vm_file)
+		fput(vma->vm_file);
+	vma->vm_file = file;
+	vma->vm_ops = &shmem_vm_ops;
+}
+
 /**
  * shmem_zero_setup - setup a shared anonymous mapping
  * @vma: the vma to be mmapped is prepared by do_mmap_pgoff
@@ -3422,10 +3432,7 @@ int shmem_zero_setup(struct vm_area_struct *vma)
 	if (IS_ERR(file))
 		return PTR_ERR(file);
 
-	if (vma->vm_file)
-		fput(vma->vm_file);
-	vma->vm_file = file;
-	vma->vm_ops = &shmem_vm_ops;
+	shmem_set_file(vma, file);
 	return 0;
 }