[PATCH v4 18/19] ext4: add some kunit stub for mballoc kunit test

[Kemeng Shi <shikemeng@huaweicloud.com>]

Multiblocks allocation will read and write block bitmap and group
descriptor which reside on disk. Add kunit stub to function
ext4_get_group_desc, ext4_read_block_bitmap_nowait, ext4_wait_block_bitmap
and ext4_mb_mark_group_bb to avoid real IO to disk.

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
---
 fs/ext4/balloc.c  | 16 ++++++++++++++++
 fs/ext4/mballoc.c |  6 ++++++
 2 files changed, 22 insertions(+)

diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c
index c1edde817be8..49411b21a190 100644
--- a/fs/ext4/balloc.c
+++ b/fs/ext4/balloc.c
@@ -22,6 +22,7 @@
 #include "mballoc.h"
 
 #include <trace/events/ext4.h>
+#include <kunit/static_stub.h>
 
 static unsigned ext4_num_base_meta_clusters(struct super_block *sb,
 					    ext4_group_t block_group);
@@ -274,6 +275,11 @@ struct ext4_group_desc * ext4_get_group_desc(struct super_block *sb,
 	struct ext4_sb_info *sbi = EXT4_SB(sb);
 	struct buffer_head *bh_p;
 
+#ifdef CONFIG_EXT4_KUNIT_TESTS
+	KUNIT_STATIC_STUB_REDIRECT(ext4_get_group_desc,
+				   sb, block_group, bh);
+#endif
+
 	if (block_group >= ngroups) {
 		ext4_error(sb, "block_group >= groups_count - block_group = %u,"
 			   " groups_count = %u", block_group, ngroups);
@@ -470,6 +476,11 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group,
 	ext4_fsblk_t bitmap_blk;
 	int err;
 
+#ifdef CONFIG_EXT4_KUNIT_TESTS
+	KUNIT_STATIC_STUB_REDIRECT(ext4_read_block_bitmap_nowait,
+				   sb, block_group, ignore_locked);
+#endif
+
 	desc = ext4_get_group_desc(sb, block_group, NULL);
 	if (!desc)
 		return ERR_PTR(-EFSCORRUPTED);
@@ -565,6 +576,11 @@ int ext4_wait_block_bitmap(struct super_block *sb, ext4_group_t block_group,
 {
 	struct ext4_group_desc *desc;
 
+#ifdef CONFIG_EXT4_KUNIT_TESTS
+	KUNIT_STATIC_STUB_REDIRECT(ext4_wait_block_bitmap,
+				   sb, block_group, bh);
+#endif
+
 	if (!buffer_new(bh))
 		return 0;
 	desc = ext4_get_group_desc(sb, block_group, NULL);
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 18713b671e46..c9b7fc0de49e 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -17,6 +17,7 @@
 #include <linux/nospec.h>
 #include <linux/backing-dev.h>
 #include <trace/events/ext4.h>
+#include <kunit/static_stub.h>
 
 /*
  * MUSTDO:
@@ -3791,6 +3792,11 @@ ext4_mb_mark_group_bb(struct ext4_mark_context *mc, ext4_group_t group,
 	int err;
 	unsigned int i, already, changed = len;
 
+#ifdef CONFIG_EXT4_KUNIT_TESTS
+	KUNIT_STATIC_STUB_REDIRECT(ext4_mb_mark_group_bb,
+				   mc, group, blkoff, len, flags);
+#endif
+
 	mc->changed = 0;
 	bitmap_bh = ext4_read_block_bitmap(sb, group);
 	if (IS_ERR(bitmap_bh))
-- 
2.30.0