2023-08-09 23:00:26

by Christoph Hellwig

Subject: [PATCH 10/13] 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 <[email protected]>
---
fs/exfat/super.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/fs/exfat/super.c b/fs/exfat/super.c
index 3c6aec96d0dc85..85b04a4064af1e 100644
--- 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 @@ static int exfat_fill_super(struct super_block *sb, struct fs_context *fc)

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,
};

--
2.39.2

2023-08-10 13:41:23

by Namjae Jeon

Subject: Re: [PATCH 10/13] exfat: free the sbi and iocharset in ->kill_sb

2023-08-10 7:05 GMT+09:00, Christoph Hellwig <[email protected]>:
> 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 <[email protected]>
Acked-by: Namjae Jeon <[email protected]>

Thanks!