exfat: free the sbi and iocharset in ->kill_sb

As a rule of thumb everything allocated to the fs_context and moved into
the super_block should be freed by ->kill_sb so that the teardown
handling doesn't need to be duplicated between the fill_super error
path and put_super.  Implement an exfat-specific kill_sb method to do
that and share the code with the mount contex free helper for the
mount error handling case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Message-Id: <20230809220545.1308228-11-hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index 3c6aec9..85b04a4 100644 (file)
--- a/fs/exfat/super.c
+++ b/fs/exfat/super.c
@@ -41,9 +41,7 @@ static void exfat_put_super(struct super_block *sb)
        mutex_unlock(&sbi->s_lock);
 
        unload_nls(sbi->nls_io);
-       exfat_free_iocharset(sbi);
        exfat_free_upcase_table(sbi);
-       kfree(sbi);
 }
 
 static int exfat_sync_fs(struct super_block *sb, int wait)
@@ -703,9 +701,6 @@ free_table:
 
 check_nls_io:
        unload_nls(sbi->nls_io);
-       exfat_free_iocharset(sbi);
-       sb->s_fs_info = NULL;
-       kfree(sbi);
        return err;
 }
 
@@ -714,14 +709,18 @@ static int exfat_get_tree(struct fs_context *fc)
        return get_tree_bdev(fc, exfat_fill_super);
 }
 
+static void exfat_free_sbi(struct exfat_sb_info *sbi)
+{
+       exfat_free_iocharset(sbi);
+       kfree(sbi);
+}
+
 static void exfat_free(struct fs_context *fc)
 {
        struct exfat_sb_info *sbi = fc->s_fs_info;
 
-       if (sbi) {
-               exfat_free_iocharset(sbi);
-               kfree(sbi);
-       }
+       if (sbi)
+               exfat_free_sbi(sbi);
 }
 
 static int exfat_reconfigure(struct fs_context *fc)
@@ -766,12 +765,21 @@ static int exfat_init_fs_context(struct fs_context *fc)
        return 0;
 }
 
+static void exfat_kill_sb(struct super_block *sb)
+{
+       struct exfat_sb_info *sbi = sb->s_fs_info;
+
+       kill_block_super(sb);
+       if (sbi)
+               exfat_free_sbi(sbi);
+}
+
 static struct file_system_type exfat_fs_type = {
        .owner                  = THIS_MODULE,
        .name                   = "exfat",
        .init_fs_context        = exfat_init_fs_context,
        .parameters             = exfat_parameters,
-       .kill_sb                = kill_block_super,
+       .kill_sb                = exfat_kill_sb,
        .fs_flags               = FS_REQUIRES_DEV,
 };