[PATCH 3/4] ext4: Use module_{subinit, subexit} helper macros

Youling Tang
2024-07-23T08:33:19Z

From: Youling Tang <tangyouling@kylinos.cn>

Use module_{subinit, subinit} to ensure that modules init and exit
are in sequence and to simplify the code.

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
---
fs/ext4/super.c | 115 ++++++++++++++----------------------------------
1 file changed, 33 insertions(+), 82 deletions(-)

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index e72145c4ae5a..207076e7e7f0 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -7302,103 +7302,54 @@ static struct file_system_type ext4_fs_type = {
};
MODULE_ALIAS_FS("ext4");

+static int register_ext(void)
+{
+ register_as_ext3();
+ register_as_ext2();
+ return register_filesystem(&ext4_fs_type);
+}
+
+static void unregister_ext(void)
+{
+ unregister_as_ext2();
+ unregister_as_ext3();
+ unregister_filesystem(&ext4_fs_type);
+}
+
+static struct subexitcall_rollback rollback;
+
+static void __exit ext4_exit_fs(void)
+{
+ ext4_destroy_lazyinit_thread();
+ module_subexit(&rollback);
+}
+
/* Shared across all ext4 file systems */
wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];

static int __init ext4_init_fs(void)
{
- int i, err;
-
ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
ext4_li_info = NULL;

/* Build-time check for flags consistency */
ext4_check_flag_values();

- for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
+ for (int i = 0; i < EXT4_WQ_HASH_SZ; i++)
init_waitqueue_head(&ext4__ioend_wq[i]);

- err = ext4_init_es();
- if (err)
- return err;
-
- err = ext4_init_pending();
- if (err)
- goto out7;
-
- err = ext4_init_post_read_processing();
- if (err)
- goto out6;
-
- err = ext4_init_pageio();
- if (err)
- goto out5;
-
- err = ext4_init_system_zone();
- if (err)
- goto out4;
-
- err = ext4_init_sysfs();
- if (err)
- goto out3;
-
- err = ext4_init_mballoc();
- if (err)
- goto out2;
- err = init_inodecache();
- if (err)
- goto out1;
-
- err = ext4_fc_init_dentry_cache();
- if (err)
- goto out05;
-
- register_as_ext3();
- register_as_ext2();
- err = register_filesystem(&ext4_fs_type);
- if (err)
- goto out;
+ module_subinit(ext4_init_es, ext4_exit_es, &rollback);
+ module_subinit(ext4_init_pending, ext4_exit_pending, &rollback);
+ module_subinit(ext4_init_post_read_processing, ext4_exit_post_read_processing, &rollback);
+ module_subinit(ext4_init_pageio, ext4_exit_pageio, &rollback);
+ module_subinit(ext4_init_system_zone, ext4_exit_system_zone, &rollback);
+ module_subinit(ext4_init_sysfs, ext4_exit_sysfs, &rollback);
+ module_subinit(ext4_init_mballoc, ext4_exit_mballoc, &rollback);
+ module_subinit(init_inodecache, destroy_inodecache, &rollback);
+ module_subinit(ext4_fc_init_dentry_cache, ext4_fc_destroy_dentry_cache, &rollback);
+ module_subinit(register_ext, unregister_ext, &rollback);

return 0;
-out:
- unregister_as_ext2();
- unregister_as_ext3();
- ext4_fc_destroy_dentry_cache();
-out05:
- destroy_inodecache();
-out1:
- ext4_exit_mballoc();
-out2:
- ext4_exit_sysfs();
-out3:
- ext4_exit_system_zone();
-out4:
- ext4_exit_pageio();
-out5:
- ext4_exit_post_read_processing();
-out6:
- ext4_exit_pending();
-out7:
- ext4_exit_es();
-
- return err;
-}
-
-static void __exit ext4_exit_fs(void)
-{
- ext4_destroy_lazyinit_thread();
- unregister_as_ext2();
- unregister_as_ext3();
- unregister_filesystem(&ext4_fs_type);
- ext4_fc_destroy_dentry_cache();
- destroy_inodecache();
- ext4_exit_mballoc();
- ext4_exit_sysfs();
- ext4_exit_system_zone();
- ext4_exit_pageio();
- ext4_exit_post_read_processing();
- ext4_exit_es();
- ext4_exit_pending();
}

MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
--
2.34.1