在 2022/9/9 17:55, JeffleXu 写道:
On 9/2/22 6:53 PM, Jia Zhu wrote:
In erofs umount scenario, erofs_fscache_unregister_cookie() is called
twice in kill_sb() and put_super().
It works for original semantics, cause 'ctx' will be set to NULL in
put_super() and will not be unregister again in kill_sb().
However, in shared domain scenario, we use refcount to maintain the
lifecycle of cookie. Unregister the cookie twice will cause it to be
released early.
For the above reasons, this patch removes duplicate unregister_cookie
and move fscache_unregister_* before shotdown_super() to prevent busy
inode(ctx->inode) when umount.
Signed-off-by: Jia Zhu <zhujia.zj@xxxxxxxxxxxxx>
---
fs/erofs/super.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 69de1731f454..667a78f0ee70 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -919,19 +919,20 @@ static void erofs_kill_sb(struct super_block *sb)
kill_litter_super(sb);
return;
}
- if (erofs_is_fscache_mode(sb))
- generic_shutdown_super(sb);
- else
- kill_block_super(sb);
-
sbi = EROFS_SB(sb);
if (!sbi)
return;
+ if (erofs_is_fscache_mode(sb)) {
+ erofs_fscache_unregister_cookie(&sbi->s_fscache);
+ erofs_fscache_unregister_fs(sb);
+ generic_shutdown_super(sb);
Generally we can't do clean ups before generic_shutdown_super(), since
generic_shutdown_super() may trigger IO, e.g. in sync_filesystem(),
though it's not the case for erofs (read-only).
How about embedding erofs_fscache_unregister_cookie() into
erofs_fscache_unregister_fs(), and thus we can check domain_id in
erofs_fscache_unregister_fs()?
Thanks.
+ } else {
+ kill_block_super(sb);
+ }
+
erofs_free_dev_context(sbi->devs);
fs_put_dax(sbi->dax_dev, NULL);
- erofs_fscache_unregister_cookie(&sbi->s_fscache);
- erofs_fscache_unregister_fs(sb);
kfree(sbi->opt.fsid);
kfree(sbi->opt.domain_id);
kfree(sbi);
@@ -951,7 +952,6 @@ static void erofs_put_super(struct super_block *sb)
iput(sbi->managed_cache);
sbi->managed_cache = NULL;
#endif
- erofs_fscache_unregister_cookie(&sbi->s_fscache);
}
struct file_system_type erofs_fs_type = {
