Fix zfs spl for building against kernel 5.1 on 0.7.x - reference: https://github.com/zfsonlinux/zfs/issues/8697

zfs-spl-0.7.9-0.7.12.patch

diff -Naur a/include/linux/file_compat.h b/include/linux/file_compat.h
--- a/include/linux/file_compat.h	2018-05-08 21:37:01.000000000 +0100
+++ b/include/linux/file_compat.h	2019-06-06 22:40:44.873699894 +0100
@@ -81,7 +81,7 @@
 	ssize_t ret;
 
 	saved_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 
 	ret = vfs_write(file, (__force const char __user *)buf, count, pos);
 
@@ -101,7 +101,7 @@
 	ssize_t ret;
 
 	saved_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 
 	ret = vfs_read(file, (void __user *)buf, count, pos);
 
diff -Naur a/module/spl/spl-vnode.c b/module/spl/spl-vnode.c
--- a/module/spl/spl-vnode.c	2019-06-06 22:38:40.830428570 +0100
+++ b/module/spl/spl-vnode.c	2019-06-06 22:40:31.706671093 +0100
@@ -608,7 +608,7 @@
 	 * size to ensure strncpy_from_user() does not fail with -EFAULT.
 	 */
 	saved_fs = get_fs();
-	set_fs(get_ds());
+	set_fs(KERNEL_DS);
 
 	rc = user_path_dir(filename, &path);
 	if (rc)