From f07485c46eb518ef7d843d7ff068c90c1a4ec53a Mon Sep 17 00:00:00 2001
From: Rob Norris <robn@despairlabs.com>
Date: Sat, 3 Aug 2024 13:57:19 +1000
Subject: [PATCH] config: remove HAVE_LINUX_BLK_CGROUP_HEADER

Sponsored-by: https://despairlabs.com/sponsor/
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>
Reviewed-by: Tino Reichardt <milky-zfs@mcmilk.de>
Signed-off-by: Rob Norris <robn@despairlabs.com>
Closes #16479
---
 config/kernel-bio.m4            | 27 ---------------------------
 module/os/linux/zfs/vdev_disk.c |  2 --
 2 files changed, 29 deletions(-)

diff --git a/config/kernel-bio.m4 b/config/kernel-bio.m4
index c53bb0d09..a00a2b48d 100644
--- a/config/kernel-bio.m4
+++ b/config/kernel-bio.m4
@@ -399,31 +399,6 @@ AC_DEFUN([ZFS_AC_KERNEL_BDEV_SUBMIT_BIO_RETURNS_VOID], [
 	])
 ])
 
-dnl #
-dnl # Linux 5.16 API
-dnl #
-dnl # The Linux 5.16 API moved struct blkcg_gq into linux/blk-cgroup.h, which
-dnl # has been around since 2015. This test looks for the presence of that
-dnl # header, so that it can be conditionally included where it exists, but
-dnl # still be backward compatible with kernels that pre-date its introduction.
-dnl #
-AC_DEFUN([ZFS_AC_KERNEL_SRC_BLK_CGROUP_HEADER], [
-	ZFS_LINUX_TEST_SRC([blk_cgroup_header], [
-		#include <linux/blk-cgroup.h>
-	], [])
-])
-
-AC_DEFUN([ZFS_AC_KERNEL_BLK_CGROUP_HEADER], [
-	AC_MSG_CHECKING([whether linux/blk-cgroup.h exists])
-	ZFS_LINUX_TEST_RESULT([blk_cgroup_header],[
-		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_LINUX_BLK_CGROUP_HEADER, 1,
-			[linux/blk-cgroup.h exists])
-	],[
-		AC_MSG_RESULT(no)
-	])
-])
-
 dnl #
 dnl # Linux 5.18 API
 dnl #
@@ -470,7 +445,6 @@ AC_DEFUN([ZFS_AC_KERNEL_SRC_BIO], [
 	ZFS_AC_KERNEL_SRC_BIO_BDEV_DISK
 	ZFS_AC_KERNEL_SRC_BDEV_SUBMIT_BIO_RETURNS_VOID
 	ZFS_AC_KERNEL_SRC_BIO_SET_DEV_MACRO
-	ZFS_AC_KERNEL_SRC_BLK_CGROUP_HEADER
 	ZFS_AC_KERNEL_SRC_BIO_ALLOC_4ARG
 ])
 
@@ -493,6 +467,5 @@ AC_DEFUN([ZFS_AC_KERNEL_BIO], [
 	ZFS_AC_KERNEL_BLKG_TRYGET
 	ZFS_AC_KERNEL_BIO_BDEV_DISK
 	ZFS_AC_KERNEL_BDEV_SUBMIT_BIO_RETURNS_VOID
-	ZFS_AC_KERNEL_BLK_CGROUP_HEADER
 	ZFS_AC_KERNEL_BIO_ALLOC_4ARG
 ])
diff --git a/module/os/linux/zfs/vdev_disk.c b/module/os/linux/zfs/vdev_disk.c
index 92510ea33..797176ba2 100644
--- a/module/os/linux/zfs/vdev_disk.c
+++ b/module/os/linux/zfs/vdev_disk.c
@@ -38,9 +38,7 @@
 #include <linux/blkpg.h>
 #include <linux/msdos_fs.h>
 #include <linux/vfs_compat.h>
-#ifdef HAVE_LINUX_BLK_CGROUP_HEADER
 #include <linux/blk-cgroup.h>
-#endif
 
 /*
  * Linux 6.8.x uses a bdev_handle as an instance/refcount for an underlying