From: Jian Yu <yujian@whamcloud.com>
Date: Wed, 13 Oct 2021 07:12:03 +0000 (-0700)
Subject: LU-14195 obdclass: change list_sort to use const pointers
X-Git-Tag: 2.14.56~129
X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=e612dcbbdd208ff0919a8c108448bbfa846e8ee6

LU-14195 obdclass: change list_sort to use const pointers

Kernel 5.10.70 commit 4f0f586bf0c898233d8f316f471a21db2abd522d
defines the list_cmp_func_t type and changes the comparison
function types of all list_sort() callers to use const pointers
to avoid type mismatches.

Change-Id: I40d37ec0f0d485d0deebaa9dc3493f2865f76ec9
Signed-off-by: Jian Yu <yujian@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/45219
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
---

diff --git a/libcfs/autoconf/lustre-libcfs.m4 b/libcfs/autoconf/lustre-libcfs.m4
index 07c4de9..64ade1b 100644
--- a/libcfs/autoconf/lustre-libcfs.m4
+++ b/libcfs/autoconf/lustre-libcfs.m4
@@ -1684,6 +1684,26 @@ LB_CHECK_LINUX_HEADER([crypto/sha2.h], [
 		[crypto/sha2.h is present])])
 ]) # LIBCFS_HAVE_CRYPTO_SHA2_HEADER
 
+#
+# LIBCFS_HAVE_LIST_CMP_FUNC_T
+#
+# kernel 5.10.70 commit 4f0f586bf0c898233d8f316f471a21db2abd522d
+# treewide: Change list_sort to use const pointers
+AC_DEFUN([LIBCFS_HAVE_LIST_CMP_FUNC_T], [
+tmp_flags="$EXTRA_KCFLAGS"
+EXTRA_KCFLAGS="-Werror -Wno-unused-variable"
+LB_CHECK_COMPILE([if list_cmp_func_t type is defined],
+list_cmp_func_t, [
+	#include <linux/list_sort.h>
+],[
+	list_cmp_func_t cmp;
+],[
+	AC_DEFINE(HAVE_LIST_CMP_FUNC_T, 1,
+		[list_cmp_func_t type is defined])
+])
+EXTRA_KCFLAGS="$tmp_flags"
+]) # LIBCFS_HAVE_LIST_CMP_FUNC_T
+
 AC_DEFUN([LIBCFS_PROG_LINUX_SRC], [
 	LIBCFS_SRC_HAVE_PROC_OPS
 
@@ -1825,6 +1845,7 @@ LIBCFS_SEC_RELEASE_SECCTX
 # 5.10
 LIBCFS_HAVE_KFREE_SENSITIVE
 LIBCFS_HAVE_CRYPTO_SHA2_HEADER
+LIBCFS_HAVE_LIST_CMP_FUNC_T
 ]) # LIBCFS_PROG_LINUX
 
 #
diff --git a/lustre/obdclass/cl_io.c b/lustre/obdclass/cl_io.c
index caf4701..dc2be4a 100644
--- a/lustre/obdclass/cl_io.c
+++ b/lustre/obdclass/cl_io.c
@@ -221,8 +221,14 @@ int cl_io_rw_init(const struct lu_env *env, struct cl_io *io,
 }
 EXPORT_SYMBOL(cl_io_rw_init);
 
+#ifdef HAVE_LIST_CMP_FUNC_T
+static int cl_lock_descr_cmp(void *priv,
+			     const struct list_head *a,
+			     const struct list_head *b)
+#else /* !HAVE_LIST_CMP_FUNC_T */
 static int cl_lock_descr_cmp(void *priv,
 			     struct list_head *a, struct list_head *b)
+#endif /* HAVE_LIST_CMP_FUNC_T */
 {
 	const struct cl_io_lock_link *l0 = list_entry(a, struct cl_io_lock_link,
 						      cill_linkage);