[PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.
To solve this issue, the ext4 test code needs to be decoupled. The ext4
test module is compiled into a separate module.

Reported-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
Closes: https://patchwork.kernel.org/project/cifs-client/patch/20260118091313.1988168-2-chenxiaosong.chenxiaosong@linux.dev/
Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
Signed-off-by: Ye Bin <yebin10@huawei.com>
---
 fs/ext4/Makefile       |   4 +-
 fs/ext4/mballoc-test.c |  81 ++++++++++++++++----------------
 fs/ext4/mballoc.c      | 102 +++++++++++++++++++++++++++++++++++++++--
 fs/ext4/mballoc.h      |  30 ++++++++++++
 4 files changed, 172 insertions(+), 45 deletions(-)

diff --git a/fs/ext4/Makefile b/fs/ext4/Makefile
index 72206a292676..d836c3fe311b 100644
--- a/fs/ext4/Makefile
+++ b/fs/ext4/Makefile
@@ -14,7 +14,7 @@ ext4-y	:= balloc.o bitmap.o block_validity.o dir.o ext4_jbd2.o extents.o \
 
 ext4-$(CONFIG_EXT4_FS_POSIX_ACL)	+= acl.o
 ext4-$(CONFIG_EXT4_FS_SECURITY)		+= xattr_security.o
-ext4-inode-test-objs			+= inode-test.o
-obj-$(CONFIG_EXT4_KUNIT_TESTS)		+= ext4-inode-test.o
+ext4-test-objs				+= inode-test.o mballoc-test.o
+obj-$(CONFIG_EXT4_KUNIT_TESTS)		+= ext4-test.o
 ext4-$(CONFIG_FS_VERITY)		+= verity.o
 ext4-$(CONFIG_FS_ENCRYPTION)		+= crypto.o
diff --git a/fs/ext4/mballoc-test.c b/fs/ext4/mballoc-test.c
index 4abb40d4561c..749ed2fc2241 100644
--- a/fs/ext4/mballoc-test.c
+++ b/fs/ext4/mballoc-test.c
@@ -8,6 +8,7 @@
 #include <linux/random.h>
 
 #include "ext4.h"
+#include "mballoc.h"
 
 struct mbt_grp_ctx {
 	struct buffer_head bitmap_bh;
@@ -337,7 +338,7 @@ ext4_mb_mark_context_stub(handle_t *handle, struct super_block *sb, bool state,
 	if (state)
 		mb_set_bits(bitmap_bh->b_data, blkoff, len);
 	else
-		mb_clear_bits(bitmap_bh->b_data, blkoff, len);
+		mb_clear_bits_test(bitmap_bh->b_data, blkoff, len);
 
 	return 0;
 }
@@ -414,14 +415,14 @@ static void test_new_blocks_simple(struct kunit *test)
 
 	/* get block at goal */
 	ar.goal = ext4_group_first_block_no(sb, goal_group);
-	found = ext4_mb_new_blocks_simple(&ar, &err);
+	found = ext4_mb_new_blocks_simple_test(&ar, &err);
 	KUNIT_ASSERT_EQ_MSG(test, ar.goal, found,
 		"failed to alloc block at goal, expected %llu found %llu",
 		ar.goal, found);
 
 	/* get block after goal in goal group */
 	ar.goal = ext4_group_first_block_no(sb, goal_group);
-	found = ext4_mb_new_blocks_simple(&ar, &err);
+	found = ext4_mb_new_blocks_simple_test(&ar, &err);
 	KUNIT_ASSERT_EQ_MSG(test, ar.goal + EXT4_C2B(sbi, 1), found,
 		"failed to alloc block after goal in goal group, expected %llu found %llu",
 		ar.goal + 1, found);
@@ -429,7 +430,7 @@ static void test_new_blocks_simple(struct kunit *test)
 	/* get block after goal group */
 	mbt_ctx_mark_used(sb, goal_group, 0, EXT4_CLUSTERS_PER_GROUP(sb));
 	ar.goal = ext4_group_first_block_no(sb, goal_group);
-	found = ext4_mb_new_blocks_simple(&ar, &err);
+	found = ext4_mb_new_blocks_simple_test(&ar, &err);
 	KUNIT_ASSERT_EQ_MSG(test,
 		ext4_group_first_block_no(sb, goal_group + 1), found,
 		"failed to alloc block after goal group, expected %llu found %llu",
@@ -439,7 +440,7 @@ static void test_new_blocks_simple(struct kunit *test)
 	for (i = goal_group; i < ext4_get_groups_count(sb); i++)
 		mbt_ctx_mark_used(sb, i, 0, EXT4_CLUSTERS_PER_GROUP(sb));
 	ar.goal = ext4_group_first_block_no(sb, goal_group);
-	found = ext4_mb_new_blocks_simple(&ar, &err);
+	found = ext4_mb_new_blocks_simple_test(&ar, &err);
 	KUNIT_ASSERT_EQ_MSG(test,
 		ext4_group_first_block_no(sb, 0) + EXT4_C2B(sbi, 1), found,
 		"failed to alloc block before goal group, expected %llu found %llu",
@@ -449,7 +450,7 @@ static void test_new_blocks_simple(struct kunit *test)
 	for (i = 0; i < ext4_get_groups_count(sb); i++)
 		mbt_ctx_mark_used(sb, i, 0, EXT4_CLUSTERS_PER_GROUP(sb));
 	ar.goal = ext4_group_first_block_no(sb, goal_group);
-	found = ext4_mb_new_blocks_simple(&ar, &err);
+	found = ext4_mb_new_blocks_simple_test(&ar, &err);
 	KUNIT_ASSERT_NE_MSG(test, err, 0,
 		"unexpectedly get block when no block is available");
 }
@@ -493,16 +494,16 @@ validate_free_blocks_simple(struct kunit *test, struct super_block *sb,
 			continue;
 
 		bitmap = mbt_ctx_bitmap(sb, i);
-		bit = mb_find_next_zero_bit(bitmap, max, 0);
+		bit = mb_find_next_zero_bit_test(bitmap, max, 0);
 		KUNIT_ASSERT_EQ_MSG(test, bit, max,
 				    "free block on unexpected group %d", i);
 	}
 
 	bitmap = mbt_ctx_bitmap(sb, goal_group);
-	bit = mb_find_next_zero_bit(bitmap, max, 0);
+	bit = mb_find_next_zero_bit_test(bitmap, max, 0);
 	KUNIT_ASSERT_EQ(test, bit, start);
 
-	bit = mb_find_next_bit(bitmap, max, bit + 1);
+	bit = mb_find_next_bit_test(bitmap, max, bit + 1);
 	KUNIT_ASSERT_EQ(test, bit, start + len);
 }
 
@@ -525,7 +526,7 @@ test_free_blocks_simple_range(struct kunit *test, ext4_group_t goal_group,
 
 	block = ext4_group_first_block_no(sb, goal_group) +
 		EXT4_C2B(sbi, start);
-	ext4_free_blocks_simple(inode, block, len);
+	ext4_free_blocks_simple_test(inode, block, len);
 	validate_free_blocks_simple(test, sb, goal_group, start, len);
 	mbt_ctx_mark_used(sb, goal_group, 0, EXT4_CLUSTERS_PER_GROUP(sb));
 }
@@ -567,15 +568,15 @@ test_mark_diskspace_used_range(struct kunit *test,
 
 	bitmap = mbt_ctx_bitmap(sb, TEST_GOAL_GROUP);
 	memset(bitmap, 0, sb->s_blocksize);
-	ret = ext4_mb_mark_diskspace_used(ac, NULL);
+	ret = ext4_mb_mark_diskspace_used_test(ac, NULL);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	max = EXT4_CLUSTERS_PER_GROUP(sb);
-	i = mb_find_next_bit(bitmap, max, 0);
+	i = mb_find_next_bit_test(bitmap, max, 0);
 	KUNIT_ASSERT_EQ(test, i, start);
-	i = mb_find_next_zero_bit(bitmap, max, i + 1);
+	i = mb_find_next_zero_bit_test(bitmap, max, i + 1);
 	KUNIT_ASSERT_EQ(test, i, start + len);
-	i = mb_find_next_bit(bitmap, max, i + 1);
+	i = mb_find_next_bit_test(bitmap, max, i + 1);
 	KUNIT_ASSERT_EQ(test, max, i);
 }
 
@@ -618,54 +619,54 @@ static void mbt_generate_buddy(struct super_block *sb, void *buddy,
 	max = EXT4_CLUSTERS_PER_GROUP(sb);
 	bb_h = buddy + sbi->s_mb_offsets[1];
 
-	off = mb_find_next_zero_bit(bb, max, 0);
+	off = mb_find_next_zero_bit_test(bb, max, 0);
 	grp->bb_first_free = off;
 	while (off < max) {
 		grp->bb_counters[0]++;
 		grp->bb_free++;
 
-		if (!(off & 1) && !mb_test_bit(off + 1, bb)) {
+		if (!(off & 1) && !mb_test_bit_test(off + 1, bb)) {
 			grp->bb_free++;
 			grp->bb_counters[0]--;
-			mb_clear_bit(off >> 1, bb_h);
+			mb_clear_bit_test(off >> 1, bb_h);
 			grp->bb_counters[1]++;
 			grp->bb_largest_free_order = 1;
 			off++;
 		}
 
-		off = mb_find_next_zero_bit(bb, max, off + 1);
+		off = mb_find_next_zero_bit_test(bb, max, off + 1);
 	}
 
 	for (order = 1; order < MB_NUM_ORDERS(sb) - 1; order++) {
 		bb = buddy + sbi->s_mb_offsets[order];
 		bb_h = buddy + sbi->s_mb_offsets[order + 1];
 		max = max >> 1;
-		off = mb_find_next_zero_bit(bb, max, 0);
+		off = mb_find_next_zero_bit_test(bb, max, 0);
 
 		while (off < max) {
-			if (!(off & 1) && !mb_test_bit(off + 1, bb)) {
+			if (!(off & 1) && !mb_test_bit_test(off + 1, bb)) {
 				mb_set_bits(bb, off, 2);
 				grp->bb_counters[order] -= 2;
-				mb_clear_bit(off >> 1, bb_h);
+				mb_clear_bit_test(off >> 1, bb_h);
 				grp->bb_counters[order + 1]++;
 				grp->bb_largest_free_order = order + 1;
 				off++;
 			}
 
-			off = mb_find_next_zero_bit(bb, max, off + 1);
+			off = mb_find_next_zero_bit_test(bb, max, off + 1);
 		}
 	}
 
 	max = EXT4_CLUSTERS_PER_GROUP(sb);
-	off = mb_find_next_zero_bit(bitmap, max, 0);
+	off = mb_find_next_zero_bit_test(bitmap, max, 0);
 	while (off < max) {
 		grp->bb_fragments++;
 
-		off = mb_find_next_bit(bitmap, max, off + 1);
+		off = mb_find_next_bit_test(bitmap, max, off + 1);
 		if (off + 1 >= max)
 			break;
 
-		off = mb_find_next_zero_bit(bitmap, max, off + 1);
+		off = mb_find_next_zero_bit_test(bitmap, max, off + 1);
 	}
 }
 
@@ -707,7 +708,7 @@ do_test_generate_buddy(struct kunit *test, struct super_block *sb, void *bitmap,
 	/* needed by validation in ext4_mb_generate_buddy */
 	ext4_grp->bb_free = mbt_grp->bb_free;
 	memset(ext4_buddy, 0xff, sb->s_blocksize);
-	ext4_mb_generate_buddy(sb, ext4_buddy, bitmap, TEST_GOAL_GROUP,
+	ext4_mb_generate_buddy_test(sb, ext4_buddy, bitmap, TEST_GOAL_GROUP,
 			       ext4_grp);
 
 	KUNIT_ASSERT_EQ(test, memcmp(mbt_buddy, ext4_buddy, sb->s_blocksize),
@@ -761,7 +762,7 @@ test_mb_mark_used_range(struct kunit *test, struct ext4_buddy *e4b,
 	ex.fe_group = TEST_GOAL_GROUP;
 
 	ext4_lock_group(sb, TEST_GOAL_GROUP);
-	mb_mark_used(e4b, &ex);
+	mb_mark_used_test(e4b, &ex);
 	ext4_unlock_group(sb, TEST_GOAL_GROUP);
 
 	mb_set_bits(bitmap, start, len);
@@ -770,7 +771,7 @@ test_mb_mark_used_range(struct kunit *test, struct ext4_buddy *e4b,
 	memset(buddy, 0xff, sb->s_blocksize);
 	for (i = 0; i < MB_NUM_ORDERS(sb); i++)
 		grp->bb_counters[i] = 0;
-	ext4_mb_generate_buddy(sb, buddy, bitmap, 0, grp);
+	ext4_mb_generate_buddy_test(sb, buddy, bitmap, 0, grp);
 
 	KUNIT_ASSERT_EQ(test, memcmp(buddy, e4b->bd_buddy, sb->s_blocksize),
 			0);
@@ -799,7 +800,7 @@ static void test_mb_mark_used(struct kunit *test)
 				bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, grp);
 
-	ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
+	ret = ext4_mb_load_buddy_test(sb, TEST_GOAL_GROUP, &e4b);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	grp->bb_free = EXT4_CLUSTERS_PER_GROUP(sb);
@@ -810,7 +811,7 @@ static void test_mb_mark_used(struct kunit *test)
 		test_mb_mark_used_range(test, &e4b, ranges[i].start,
 					ranges[i].len, bitmap, buddy, grp);
 
-	ext4_mb_unload_buddy(&e4b);
+	ext4_mb_unload_buddy_test(&e4b);
 }
 
 static void
@@ -826,16 +827,16 @@ test_mb_free_blocks_range(struct kunit *test, struct ext4_buddy *e4b,
 		return;
 
 	ext4_lock_group(sb, e4b->bd_group);
-	mb_free_blocks(NULL, e4b, start, len);
+	mb_free_blocks_test(NULL, e4b, start, len);
 	ext4_unlock_group(sb, e4b->bd_group);
 
-	mb_clear_bits(bitmap, start, len);
+	mb_clear_bits_test(bitmap, start, len);
 	/* bypass bb_free validatoin in ext4_mb_generate_buddy */
 	grp->bb_free += len;
 	memset(buddy, 0xff, sb->s_blocksize);
 	for (i = 0; i < MB_NUM_ORDERS(sb); i++)
 		grp->bb_counters[i] = 0;
-	ext4_mb_generate_buddy(sb, buddy, bitmap, 0, grp);
+	ext4_mb_generate_buddy_test(sb, buddy, bitmap, 0, grp);
 
 	KUNIT_ASSERT_EQ(test, memcmp(buddy, e4b->bd_buddy, sb->s_blocksize),
 			0);
@@ -866,7 +867,7 @@ static void test_mb_free_blocks(struct kunit *test)
 				bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, grp);
 
-	ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
+	ret = ext4_mb_load_buddy_test(sb, TEST_GOAL_GROUP, &e4b);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	ex.fe_start = 0;
@@ -874,7 +875,7 @@ static void test_mb_free_blocks(struct kunit *test)
 	ex.fe_group = TEST_GOAL_GROUP;
 
 	ext4_lock_group(sb, TEST_GOAL_GROUP);
-	mb_mark_used(&e4b, &ex);
+	mb_mark_used_test(&e4b, &ex);
 	ext4_unlock_group(sb, TEST_GOAL_GROUP);
 
 	grp->bb_free = 0;
@@ -887,7 +888,7 @@ static void test_mb_free_blocks(struct kunit *test)
 		test_mb_free_blocks_range(test, &e4b, ranges[i].start,
 					  ranges[i].len, bitmap, buddy, grp);
 
-	ext4_mb_unload_buddy(&e4b);
+	ext4_mb_unload_buddy_test(&e4b);
 }
 
 #define COUNT_FOR_ESTIMATE 100000
@@ -905,7 +906,7 @@ static void test_mb_mark_used_cost(struct kunit *test)
 	if (sb->s_blocksize > PAGE_SIZE)
 		kunit_skip(test, "blocksize exceeds pagesize");
 
-	ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
+	ret = ext4_mb_load_buddy_test(sb, TEST_GOAL_GROUP, &e4b);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	ex.fe_group = TEST_GOAL_GROUP;
@@ -919,7 +920,7 @@ static void test_mb_mark_used_cost(struct kunit *test)
 			ex.fe_start = ranges[i].start;
 			ex.fe_len = ranges[i].len;
 			ext4_lock_group(sb, TEST_GOAL_GROUP);
-			mb_mark_used(&e4b, &ex);
+			mb_mark_used_test(&e4b, &ex);
 			ext4_unlock_group(sb, TEST_GOAL_GROUP);
 		}
 		end = jiffies;
@@ -930,14 +931,14 @@ static void test_mb_mark_used_cost(struct kunit *test)
 				continue;
 
 			ext4_lock_group(sb, TEST_GOAL_GROUP);
-			mb_free_blocks(NULL, &e4b, ranges[i].start,
+			mb_free_blocks_test(NULL, &e4b, ranges[i].start,
 				       ranges[i].len);
 			ext4_unlock_group(sb, TEST_GOAL_GROUP);
 		}
 	}
 
 	kunit_info(test, "costed jiffies %lu\n", all);
-	ext4_mb_unload_buddy(&e4b);
+	ext4_mb_unload_buddy_test(&e4b);
 }
 
 static const struct mbt_ext4_block_layout mbt_test_layouts[] = {
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index b99d1a7e580e..bd40fc4d3d93 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4086,7 +4086,7 @@ void ext4_exit_mballoc(void)
 
 #define EXT4_MB_BITMAP_MARKED_CHECK 0x0001
 #define EXT4_MB_SYNC_UPDATE 0x0002
-static int
+int
 ext4_mb_mark_context(handle_t *handle, struct super_block *sb, bool state,
 		     ext4_group_t group, ext4_grpblk_t blkoff,
 		     ext4_grpblk_t len, int flags, ext4_grpblk_t *ret_changed)
@@ -7190,6 +7190,102 @@ ext4_mballoc_query_range(
 	return error;
 }
 
-#ifdef CONFIG_EXT4_KUNIT_TESTS
-#include "mballoc-test.c"
+#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
+void mb_clear_bits_test(void *bm, int cur, int len)
+{
+	 mb_clear_bits(bm, cur, len);
+}
+EXPORT_SYMBOL_GPL(mb_clear_bits_test);
+
+ext4_fsblk_t
+ext4_mb_new_blocks_simple_test(struct ext4_allocation_request *ar,
+			       int *errp)
+{
+	return ext4_mb_new_blocks_simple(ar, errp);
+}
+EXPORT_SYMBOL_GPL(ext4_mb_new_blocks_simple_test);
+
+int mb_find_next_zero_bit_test(void *addr, int max, int start)
+{
+	return mb_find_next_zero_bit(addr, max, start);
+}
+EXPORT_SYMBOL_GPL(mb_find_next_zero_bit_test);
+
+int mb_find_next_bit_test(void *addr, int max, int start)
+{
+	return mb_find_next_bit(addr, max, start);
+}
+EXPORT_SYMBOL_GPL(mb_find_next_bit_test);
+
+void mb_clear_bit_test(int bit, void *addr)
+{
+	mb_clear_bit(bit, addr);
+}
+EXPORT_SYMBOL_GPL(mb_clear_bit_test);
+
+int mb_test_bit_test(int bit, void *addr)
+{
+	return mb_test_bit(bit, addr);
+}
+EXPORT_SYMBOL_GPL(mb_test_bit_test);
+
+int ext4_mb_mark_diskspace_used_test(struct ext4_allocation_context *ac,
+				     handle_t *handle)
+{
+	return ext4_mb_mark_diskspace_used(ac, handle);
+}
+EXPORT_SYMBOL_GPL(ext4_mb_mark_diskspace_used_test);
+
+int mb_mark_used_test(struct ext4_buddy *e4b, struct ext4_free_extent *ex)
+{
+	return mb_mark_used(e4b, ex);
+}
+EXPORT_SYMBOL_GPL(mb_mark_used_test);
+
+void ext4_mb_generate_buddy_test(struct super_block *sb, void *buddy,
+				 void *bitmap, ext4_group_t group,
+				 struct ext4_group_info *grp)
+{
+	ext4_mb_generate_buddy(sb, buddy, bitmap, group, grp);
+}
+EXPORT_SYMBOL_GPL(ext4_mb_generate_buddy_test);
+
+int ext4_mb_load_buddy_test(struct super_block *sb, ext4_group_t group,
+			    struct ext4_buddy *e4b)
+{
+	return ext4_mb_load_buddy(sb, group, e4b);
+}
+EXPORT_SYMBOL_GPL(ext4_mb_load_buddy_test);
+
+void ext4_mb_unload_buddy_test(struct ext4_buddy *e4b)
+{
+	ext4_mb_unload_buddy(e4b);
+}
+EXPORT_SYMBOL_GPL(ext4_mb_unload_buddy_test);
+
+void mb_free_blocks_test(struct inode *inode, struct ext4_buddy *e4b,
+			 int first, int count)
+{
+	mb_free_blocks(inode, e4b, first, count);
+}
+EXPORT_SYMBOL_GPL(mb_free_blocks_test);
+
+void ext4_free_blocks_simple_test(struct inode *inode, ext4_fsblk_t block,
+				  unsigned long count)
+{
+	return ext4_free_blocks_simple(inode, block, count);
+}
+EXPORT_SYMBOL_GPL(ext4_free_blocks_simple_test);
+
+EXPORT_SYMBOL_GPL(ext4_wait_block_bitmap);
+EXPORT_SYMBOL_GPL(ext4_mb_init);
+EXPORT_SYMBOL_GPL(ext4_get_group_desc);
+EXPORT_SYMBOL_GPL(ext4_count_free_clusters);
+EXPORT_SYMBOL_GPL(ext4_get_group_info);
+EXPORT_SYMBOL_GPL(ext4_free_group_clusters_set);
+EXPORT_SYMBOL_GPL(ext4_mb_release);
+EXPORT_SYMBOL_GPL(ext4_read_block_bitmap_nowait);
+EXPORT_SYMBOL_GPL(mb_set_bits);
+EXPORT_SYMBOL_GPL(ext4_fc_init_inode);
+EXPORT_SYMBOL_GPL(ext4_mb_mark_context);
 #endif
diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h
index 15a049f05d04..b32e03e7ae8d 100644
--- a/fs/ext4/mballoc.h
+++ b/fs/ext4/mballoc.h
@@ -270,4 +270,34 @@ ext4_mballoc_query_range(
 	ext4_mballoc_query_range_fn	formatter,
 	void				*priv);
 
+#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
+extern void mb_clear_bits_test(void *bm, int cur, int len);
+extern int ext4_mb_mark_context(handle_t *handle,
+		struct super_block *sb, bool state,
+		ext4_group_t group, ext4_grpblk_t blkoff,
+		ext4_grpblk_t len, int flags,
+		ext4_grpblk_t *ret_changed);
+extern ext4_fsblk_t
+ext4_mb_new_blocks_simple_test(struct ext4_allocation_request *ar,
+			       int *errp);
+extern int mb_find_next_zero_bit_test(void *addr, int max, int start);
+extern int mb_find_next_bit_test(void *addr, int max, int start);
+extern void mb_clear_bit_test(int bit, void *addr);
+extern int mb_test_bit_test(int bit, void *addr);
+extern int
+ext4_mb_mark_diskspace_used_test(struct ext4_allocation_context *ac,
+				 handle_t *handle);
+extern int mb_mark_used_test(struct ext4_buddy *e4b,
+			     struct ext4_free_extent *ex);
+extern void ext4_mb_generate_buddy_test(struct super_block *sb,
+		void *buddy, void *bitmap, ext4_group_t group,
+		struct ext4_group_info *grp);
+extern int ext4_mb_load_buddy_test(struct super_block *sb,
+		ext4_group_t group, struct ext4_buddy *e4b);
+extern void ext4_mb_unload_buddy_test(struct ext4_buddy *e4b);
+extern void mb_free_blocks_test(struct inode *inode,
+		struct ext4_buddy *e4b, int first, int count);
+extern void ext4_free_blocks_simple_test(struct inode *inode,
+		ext4_fsblk_t block, unsigned long count);
+#endif
 #endif
-- 
2.34.1

Re: [PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[Jan Kara]

On Thu 26-02-26 19:09:17, Ye Bin wrote:
> From: Ye Bin <yebin10@huawei.com>
> 
> Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.
> To solve this issue, the ext4 test code needs to be decoupled. The ext4
> test module is compiled into a separate module.
> 
> Reported-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
> Closes: https://patchwork.kernel.org/project/cifs-client/patch/20260118091313.1988168-2-chenxiaosong.chenxiaosong@linux.dev/
> Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
> Signed-off-by: Ye Bin <yebin10@huawei.com>

I think this is a good idea but:

> -#ifdef CONFIG_EXT4_KUNIT_TESTS
> -#include "mballoc-test.c"
> +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
> +void mb_clear_bits_test(void *bm, int cur, int len)
> +{
> +	 mb_clear_bits(bm, cur, len);
> +}
> +EXPORT_SYMBOL_GPL(mb_clear_bits_test);

Please use EXPORT_SYMBOL_FOR_MODULES() for the exports to make them clearly
ext4 internal. Thanks!

								Honza

> +
> +ext4_fsblk_t
> +ext4_mb_new_blocks_simple_test(struct ext4_allocation_request *ar,
> +			       int *errp)
> +{
> +	return ext4_mb_new_blocks_simple(ar, errp);
> +}
> +EXPORT_SYMBOL_GPL(ext4_mb_new_blocks_simple_test);
> +
> +int mb_find_next_zero_bit_test(void *addr, int max, int start)
> +{
> +	return mb_find_next_zero_bit(addr, max, start);
> +}
> +EXPORT_SYMBOL_GPL(mb_find_next_zero_bit_test);
> +
> +int mb_find_next_bit_test(void *addr, int max, int start)
> +{
> +	return mb_find_next_bit(addr, max, start);
> +}
> +EXPORT_SYMBOL_GPL(mb_find_next_bit_test);
> +
> +void mb_clear_bit_test(int bit, void *addr)
> +{
> +	mb_clear_bit(bit, addr);
> +}
> +EXPORT_SYMBOL_GPL(mb_clear_bit_test);
> +
> +int mb_test_bit_test(int bit, void *addr)
> +{
> +	return mb_test_bit(bit, addr);
> +}
> +EXPORT_SYMBOL_GPL(mb_test_bit_test);
> +
> +int ext4_mb_mark_diskspace_used_test(struct ext4_allocation_context *ac,
> +				     handle_t *handle)
> +{
> +	return ext4_mb_mark_diskspace_used(ac, handle);
> +}
> +EXPORT_SYMBOL_GPL(ext4_mb_mark_diskspace_used_test);
> +
> +int mb_mark_used_test(struct ext4_buddy *e4b, struct ext4_free_extent *ex)
> +{
> +	return mb_mark_used(e4b, ex);
> +}
> +EXPORT_SYMBOL_GPL(mb_mark_used_test);
> +
> +void ext4_mb_generate_buddy_test(struct super_block *sb, void *buddy,
> +				 void *bitmap, ext4_group_t group,
> +				 struct ext4_group_info *grp)
> +{
> +	ext4_mb_generate_buddy(sb, buddy, bitmap, group, grp);
> +}
> +EXPORT_SYMBOL_GPL(ext4_mb_generate_buddy_test);
> +
> +int ext4_mb_load_buddy_test(struct super_block *sb, ext4_group_t group,
> +			    struct ext4_buddy *e4b)
> +{
> +	return ext4_mb_load_buddy(sb, group, e4b);
> +}
> +EXPORT_SYMBOL_GPL(ext4_mb_load_buddy_test);
> +
> +void ext4_mb_unload_buddy_test(struct ext4_buddy *e4b)
> +{
> +	ext4_mb_unload_buddy(e4b);
> +}
> +EXPORT_SYMBOL_GPL(ext4_mb_unload_buddy_test);
> +
> +void mb_free_blocks_test(struct inode *inode, struct ext4_buddy *e4b,
> +			 int first, int count)
> +{
> +	mb_free_blocks(inode, e4b, first, count);
> +}
> +EXPORT_SYMBOL_GPL(mb_free_blocks_test);
> +
> +void ext4_free_blocks_simple_test(struct inode *inode, ext4_fsblk_t block,
> +				  unsigned long count)
> +{
> +	return ext4_free_blocks_simple(inode, block, count);
> +}
> +EXPORT_SYMBOL_GPL(ext4_free_blocks_simple_test);
> +
> +EXPORT_SYMBOL_GPL(ext4_wait_block_bitmap);
> +EXPORT_SYMBOL_GPL(ext4_mb_init);
> +EXPORT_SYMBOL_GPL(ext4_get_group_desc);
> +EXPORT_SYMBOL_GPL(ext4_count_free_clusters);
> +EXPORT_SYMBOL_GPL(ext4_get_group_info);
> +EXPORT_SYMBOL_GPL(ext4_free_group_clusters_set);
> +EXPORT_SYMBOL_GPL(ext4_mb_release);
> +EXPORT_SYMBOL_GPL(ext4_read_block_bitmap_nowait);
> +EXPORT_SYMBOL_GPL(mb_set_bits);
> +EXPORT_SYMBOL_GPL(ext4_fc_init_inode);
> +EXPORT_SYMBOL_GPL(ext4_mb_mark_context);
>  #endif
> diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h
> index 15a049f05d04..b32e03e7ae8d 100644
> --- a/fs/ext4/mballoc.h
> +++ b/fs/ext4/mballoc.h
> @@ -270,4 +270,34 @@ ext4_mballoc_query_range(
>  	ext4_mballoc_query_range_fn	formatter,
>  	void				*priv);
>  
> +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
> +extern void mb_clear_bits_test(void *bm, int cur, int len);
> +extern int ext4_mb_mark_context(handle_t *handle,
> +		struct super_block *sb, bool state,
> +		ext4_group_t group, ext4_grpblk_t blkoff,
> +		ext4_grpblk_t len, int flags,
> +		ext4_grpblk_t *ret_changed);
> +extern ext4_fsblk_t
> +ext4_mb_new_blocks_simple_test(struct ext4_allocation_request *ar,
> +			       int *errp);
> +extern int mb_find_next_zero_bit_test(void *addr, int max, int start);
> +extern int mb_find_next_bit_test(void *addr, int max, int start);
> +extern void mb_clear_bit_test(int bit, void *addr);
> +extern int mb_test_bit_test(int bit, void *addr);
> +extern int
> +ext4_mb_mark_diskspace_used_test(struct ext4_allocation_context *ac,
> +				 handle_t *handle);
> +extern int mb_mark_used_test(struct ext4_buddy *e4b,
> +			     struct ext4_free_extent *ex);
> +extern void ext4_mb_generate_buddy_test(struct super_block *sb,
> +		void *buddy, void *bitmap, ext4_group_t group,
> +		struct ext4_group_info *grp);
> +extern int ext4_mb_load_buddy_test(struct super_block *sb,
> +		ext4_group_t group, struct ext4_buddy *e4b);
> +extern void ext4_mb_unload_buddy_test(struct ext4_buddy *e4b);
> +extern void mb_free_blocks_test(struct inode *inode,
> +		struct ext4_buddy *e4b, int first, int count);
> +extern void ext4_free_blocks_simple_test(struct inode *inode,
> +		ext4_fsblk_t block, unsigned long count);
> +#endif
>  #endif
> -- 
> 2.34.1
> 
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[yebin (H)]

On 2026/2/26 21:42, Jan Kara wrote:
> On Thu 26-02-26 19:09:17, Ye Bin wrote:
>> From: Ye Bin <yebin10@huawei.com>
>>
>> Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.
>> To solve this issue, the ext4 test code needs to be decoupled. The ext4
>> test module is compiled into a separate module.
>>
>> Reported-by: ChenXiaoSong <chenxiaosong@kylinos.cn>
>> Closes: https://patchwork.kernel.org/project/cifs-client/patch/20260118091313.1988168-2-chenxiaosong.chenxiaosong@linux.dev/
>> Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
>> Signed-off-by: Ye Bin <yebin10@huawei.com>
>
> I think this is a good idea but:
>
>> -#ifdef CONFIG_EXT4_KUNIT_TESTS
>> -#include "mballoc-test.c"
>> +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
>> +void mb_clear_bits_test(void *bm, int cur, int len)
>> +{
>> +	 mb_clear_bits(bm, cur, len);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_clear_bits_test);
>
> Please use EXPORT_SYMBOL_FOR_MODULES() for the exports to make them clearly
> ext4 internal. Thanks!
>
> 								Honza
>
Thank you for your suggestion.I will send a new version.
>> +
>> +ext4_fsblk_t
>> +ext4_mb_new_blocks_simple_test(struct ext4_allocation_request *ar,
>> +			       int *errp)
>> +{
>> +	return ext4_mb_new_blocks_simple(ar, errp);
>> +}
>> +EXPORT_SYMBOL_GPL(ext4_mb_new_blocks_simple_test);
>> +
>> +int mb_find_next_zero_bit_test(void *addr, int max, int start)
>> +{
>> +	return mb_find_next_zero_bit(addr, max, start);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_find_next_zero_bit_test);
>> +
>> +int mb_find_next_bit_test(void *addr, int max, int start)
>> +{
>> +	return mb_find_next_bit(addr, max, start);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_find_next_bit_test);
>> +
>> +void mb_clear_bit_test(int bit, void *addr)
>> +{
>> +	mb_clear_bit(bit, addr);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_clear_bit_test);
>> +
>> +int mb_test_bit_test(int bit, void *addr)
>> +{
>> +	return mb_test_bit(bit, addr);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_test_bit_test);
>> +
>> +int ext4_mb_mark_diskspace_used_test(struct ext4_allocation_context *ac,
>> +				     handle_t *handle)
>> +{
>> +	return ext4_mb_mark_diskspace_used(ac, handle);
>> +}
>> +EXPORT_SYMBOL_GPL(ext4_mb_mark_diskspace_used_test);
>> +
>> +int mb_mark_used_test(struct ext4_buddy *e4b, struct ext4_free_extent *ex)
>> +{
>> +	return mb_mark_used(e4b, ex);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_mark_used_test);
>> +
>> +void ext4_mb_generate_buddy_test(struct super_block *sb, void *buddy,
>> +				 void *bitmap, ext4_group_t group,
>> +				 struct ext4_group_info *grp)
>> +{
>> +	ext4_mb_generate_buddy(sb, buddy, bitmap, group, grp);
>> +}
>> +EXPORT_SYMBOL_GPL(ext4_mb_generate_buddy_test);
>> +
>> +int ext4_mb_load_buddy_test(struct super_block *sb, ext4_group_t group,
>> +			    struct ext4_buddy *e4b)
>> +{
>> +	return ext4_mb_load_buddy(sb, group, e4b);
>> +}
>> +EXPORT_SYMBOL_GPL(ext4_mb_load_buddy_test);
>> +
>> +void ext4_mb_unload_buddy_test(struct ext4_buddy *e4b)
>> +{
>> +	ext4_mb_unload_buddy(e4b);
>> +}
>> +EXPORT_SYMBOL_GPL(ext4_mb_unload_buddy_test);
>> +
>> +void mb_free_blocks_test(struct inode *inode, struct ext4_buddy *e4b,
>> +			 int first, int count)
>> +{
>> +	mb_free_blocks(inode, e4b, first, count);
>> +}
>> +EXPORT_SYMBOL_GPL(mb_free_blocks_test);
>> +
>> +void ext4_free_blocks_simple_test(struct inode *inode, ext4_fsblk_t block,
>> +				  unsigned long count)
>> +{
>> +	return ext4_free_blocks_simple(inode, block, count);
>> +}
>> +EXPORT_SYMBOL_GPL(ext4_free_blocks_simple_test);
>> +
>> +EXPORT_SYMBOL_GPL(ext4_wait_block_bitmap);
>> +EXPORT_SYMBOL_GPL(ext4_mb_init);
>> +EXPORT_SYMBOL_GPL(ext4_get_group_desc);
>> +EXPORT_SYMBOL_GPL(ext4_count_free_clusters);
>> +EXPORT_SYMBOL_GPL(ext4_get_group_info);
>> +EXPORT_SYMBOL_GPL(ext4_free_group_clusters_set);
>> +EXPORT_SYMBOL_GPL(ext4_mb_release);
>> +EXPORT_SYMBOL_GPL(ext4_read_block_bitmap_nowait);
>> +EXPORT_SYMBOL_GPL(mb_set_bits);
>> +EXPORT_SYMBOL_GPL(ext4_fc_init_inode);
>> +EXPORT_SYMBOL_GPL(ext4_mb_mark_context);
>>   #endif
>> diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h
>> index 15a049f05d04..b32e03e7ae8d 100644
>> --- a/fs/ext4/mballoc.h
>> +++ b/fs/ext4/mballoc.h
>> @@ -270,4 +270,34 @@ ext4_mballoc_query_range(
>>   	ext4_mballoc_query_range_fn	formatter,
>>   	void				*priv);
>>
>> +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
>> +extern void mb_clear_bits_test(void *bm, int cur, int len);
>> +extern int ext4_mb_mark_context(handle_t *handle,
>> +		struct super_block *sb, bool state,
>> +		ext4_group_t group, ext4_grpblk_t blkoff,
>> +		ext4_grpblk_t len, int flags,
>> +		ext4_grpblk_t *ret_changed);
>> +extern ext4_fsblk_t
>> +ext4_mb_new_blocks_simple_test(struct ext4_allocation_request *ar,
>> +			       int *errp);
>> +extern int mb_find_next_zero_bit_test(void *addr, int max, int start);
>> +extern int mb_find_next_bit_test(void *addr, int max, int start);
>> +extern void mb_clear_bit_test(int bit, void *addr);
>> +extern int mb_test_bit_test(int bit, void *addr);
>> +extern int
>> +ext4_mb_mark_diskspace_used_test(struct ext4_allocation_context *ac,
>> +				 handle_t *handle);
>> +extern int mb_mark_used_test(struct ext4_buddy *e4b,
>> +			     struct ext4_free_extent *ex);
>> +extern void ext4_mb_generate_buddy_test(struct super_block *sb,
>> +		void *buddy, void *bitmap, ext4_group_t group,
>> +		struct ext4_group_info *grp);
>> +extern int ext4_mb_load_buddy_test(struct super_block *sb,
>> +		ext4_group_t group, struct ext4_buddy *e4b);
>> +extern void ext4_mb_unload_buddy_test(struct ext4_buddy *e4b);
>> +extern void mb_free_blocks_test(struct inode *inode,
>> +		struct ext4_buddy *e4b, int first, int count);
>> +extern void ext4_free_blocks_simple_test(struct inode *inode,
>> +		ext4_fsblk_t block, unsigned long count);
>> +#endif
>>   #endif
>> --
>> 2.34.1
>>

[PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[Ye Bin]

From: Ye Bin <yebin10@huawei.com>

Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.

EXT4_FS      KUNIT    EXT4_KUNIT_TESTS
Y              Y         Y
Y              Y         M
Y              M         M // This case will lead to link error
M              Y         M
M              M         M

Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
Signed-off-by: Ye Bin <yebin10@huawei.com>
---
 fs/ext4/mballoc.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index e817a758801d..0fbd2dfae497 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -7191,6 +7191,10 @@ ext4_mballoc_query_range(
 	return error;
 }
 
-#ifdef CONFIG_EXT4_KUNIT_TESTS
+#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
+#if IS_BUILTIN(CONFIG_EXT4_FS) && IS_MODULE(CONFIG_KUNIT)
+/* This case will lead to link error. */
+#else
 #include "mballoc-test.c"
 #endif
+#endif
-- 
2.34.1

Re: [PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[Ojaswin Mujoo]

On Mon, Jan 19, 2026 at 09:12:57PM +0800, Ye Bin wrote:
> From: Ye Bin <yebin10@huawei.com>
> 
> Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.
> 
> EXT4_FS      KUNIT    EXT4_KUNIT_TESTS
> Y              Y         Y
> Y              Y         M
> Y              M         M // This case will lead to link error
> M              Y         M
> M              M         M
> 
> Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
> Signed-off-by: Ye Bin <yebin10@huawei.com>
> ---
>  fs/ext4/mballoc.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> index e817a758801d..0fbd2dfae497 100644
> --- a/fs/ext4/mballoc.c
> +++ b/fs/ext4/mballoc.c
> @@ -7191,6 +7191,10 @@ ext4_mballoc_query_range(
>  	return error;
>  }
>  
> -#ifdef CONFIG_EXT4_KUNIT_TESTS
> +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
> +#if IS_BUILTIN(CONFIG_EXT4_FS) && IS_MODULE(CONFIG_KUNIT)
> +/* This case will lead to link error. */
> +#else
>  #include "mballoc-test.c"
>  #endif
> +#endif

Hi Ye Bin,

Thanks for pointing out this issue but your solution seems to be having
a side effect of making ext4.ko depend on kunit.ko.

  modinfo ext4.ko
  license:        GPL
  license:        GPL
  description:    Fourth Extended Filesystem
  author:         Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others
  alias:          fs-ext4
  alias:          ext3
  alias:          fs-ext3
  depends:        kunit
  intree:         Y
  name:           ext4
  retpoline:      Y
  vermagic:       6.19.0-rc4-xfstests-g326263653b81-dirty SMP preempt mod_unload

That means we won't be able to insert ext4 module without having kunit.
This is not the behavior we want. I think a more simpler fix here could
be:

  #if IS_BUILTIN(CONFIG_KUNIT) && IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
  #include "mballoc-test.c"
  #endif

So basically, as long as KUNIT=y and EXT4_KUNIT_TESTS=y/m we will run
these tests, otherwise we won't. This also removes the dependency issue.

What do you think?

Regards,
ojaswin

> -- 
> 2.34.1
> 

Re: [PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[yebin]

On 2026/1/20 16:45, Ojaswin Mujoo wrote:
> On Mon, Jan 19, 2026 at 09:12:57PM +0800, Ye Bin wrote:
>> From: Ye Bin <yebin10@huawei.com>
>>
>> Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.
>>
>> EXT4_FS      KUNIT    EXT4_KUNIT_TESTS
>> Y              Y         Y
>> Y              Y         M
>> Y              M         M // This case will lead to link error
>> M              Y         M
>> M              M         M
>>
>> Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
>> Signed-off-by: Ye Bin <yebin10@huawei.com>
>> ---
>>   fs/ext4/mballoc.c | 6 +++++-
>>   1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
>> index e817a758801d..0fbd2dfae497 100644
>> --- a/fs/ext4/mballoc.c
>> +++ b/fs/ext4/mballoc.c
>> @@ -7191,6 +7191,10 @@ ext4_mballoc_query_range(
>>   	return error;
>>   }
>>
>> -#ifdef CONFIG_EXT4_KUNIT_TESTS
>> +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
>> +#if IS_BUILTIN(CONFIG_EXT4_FS) && IS_MODULE(CONFIG_KUNIT)
>> +/* This case will lead to link error. */
>> +#else
>>   #include "mballoc-test.c"
>>   #endif
>> +#endif
>
> Hi Ye Bin,
>
> Thanks for pointing out this issue but your solution seems to be having
> a side effect of making ext4.ko depend on kunit.ko.
>
>    modinfo ext4.ko
>    license:        GPL
>    license:        GPL
>    description:    Fourth Extended Filesystem
>    author:         Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others
>    alias:          fs-ext4
>    alias:          ext3
>    alias:          fs-ext3
>    depends:        kunit
>    intree:         Y
>    name:           ext4
>    retpoline:      Y
>    vermagic:       6.19.0-rc4-xfstests-g326263653b81-dirty SMP preempt mod_unload
>
> That means we won't be able to insert ext4 module without having kunit.

Thank you for your reply.
In my opinion, if the CONFIG_EXT4_KUNIT_TESTS configuration is enabled 
and ext4.ko uses symbols from kunit.ko, then it is normal for ext4.ko to 
depend on kunit.ko.

> This is not the behavior we want. I think a more simpler fix here could
> be:
>
>    #if IS_BUILTIN(CONFIG_KUNIT) && IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
>    #include "mballoc-test.c"
>    #endif
>
> So basically, as long as KUNIT=y and EXT4_KUNIT_TESTS=y/m we will run
> these tests, otherwise we won't. This also removes the dependency issue.
>
> What do you think?
>
> Regards,
> ojaswin
>
>> --
>> 2.34.1
>>
>

Re: [PATCH] ext4: fix mballoc-test.c is not compiled when EXT4_KUNIT_TESTS=M

[Ojaswin Mujoo]

On Wed, Jan 21, 2026 at 05:04:12PM +0800, yebin wrote:
> 
> 
> On 2026/1/20 16:45, Ojaswin Mujoo wrote:
> > On Mon, Jan 19, 2026 at 09:12:57PM +0800, Ye Bin wrote:
> > > From: Ye Bin <yebin10@huawei.com>
> > > 
> > > Now, only EXT4_KUNIT_TESTS=Y testcase will be compiled in 'mballoc.c'.
> > > 
> > > EXT4_FS      KUNIT    EXT4_KUNIT_TESTS
> > > Y              Y         Y
> > > Y              Y         M
> > > Y              M         M // This case will lead to link error
> > > M              Y         M
> > > M              M         M
> > > 
> > > Fixes: 7c9fa399a369 ("ext4: add first unit test for ext4_mb_new_blocks_simple in mballoc")
> > > Signed-off-by: Ye Bin <yebin10@huawei.com>
> > > ---
> > >   fs/ext4/mballoc.c | 6 +++++-
> > >   1 file changed, 5 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
> > > index e817a758801d..0fbd2dfae497 100644
> > > --- a/fs/ext4/mballoc.c
> > > +++ b/fs/ext4/mballoc.c
> > > @@ -7191,6 +7191,10 @@ ext4_mballoc_query_range(
> > >   	return error;
> > >   }
> > > 
> > > -#ifdef CONFIG_EXT4_KUNIT_TESTS
> > > +#if IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
> > > +#if IS_BUILTIN(CONFIG_EXT4_FS) && IS_MODULE(CONFIG_KUNIT)
> > > +/* This case will lead to link error. */
> > > +#else
> > >   #include "mballoc-test.c"
> > >   #endif
> > > +#endif
> > 
> > Hi Ye Bin,
> > 
> > Thanks for pointing out this issue but your solution seems to be having
> > a side effect of making ext4.ko depend on kunit.ko.
> > 
> >    modinfo ext4.ko
> >    license:        GPL
> >    license:        GPL
> >    description:    Fourth Extended Filesystem
> >    author:         Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others
> >    alias:          fs-ext4
> >    alias:          ext3
> >    alias:          fs-ext3
> >    depends:        kunit
> >    intree:         Y
> >    name:           ext4
> >    retpoline:      Y
> >    vermagic:       6.19.0-rc4-xfstests-g326263653b81-dirty SMP preempt mod_unload
> > 
> > That means we won't be able to insert ext4 module without having kunit.
> 
> Thank you for your reply.
> In my opinion, if the CONFIG_EXT4_KUNIT_TESTS configuration is enabled and
> ext4.ko uses symbols from kunit.ko, then it is normal for ext4.ko to depend
> on kunit.ko.

Hi Ye,

I just feel it adds a dependency that might catch people by surprise.
For example, I'm looking at some RHEL kernel configs, we have EXT4_KUNIT_TESTS=m, 
KUNIT=m, EXT4=m. So incase this patch reaches some distros in future, we
will can have kunit module inserted everytime someone wants to use ext4 in
production, which is infact not recommended by the Kunit docs itself.

I still feel we should avoid this dependency. Eventually we may need to
see if can just build the tests as a module [1] rather than #include
method to avoid these issues.

Regards,
ojaswin


[1] https://docs.kernel.org/dev-tools/kunit/usage.html#testing-static-functions

> 
> > This is not the behavior we want. I think a more simpler fix here could
> > be:
> > 
> >    #if IS_BUILTIN(CONFIG_KUNIT) && IS_ENABLED(CONFIG_EXT4_KUNIT_TESTS)
> >    #include "mballoc-test.c"
> >    #endif
> > 
> > So basically, as long as KUNIT=y and EXT4_KUNIT_TESTS=y/m we will run
> > these tests, otherwise we won't. This also removes the dependency issue.
> > 
> > What do you think?
> > 
> > Regards,
> > ojaswin
> > 
> > > --
> > > 2.34.1
> > > 
> > 
>