From: Joseph Qi joseph.qi@linux.alibaba.com Subject: jbd2: export jbd2_journal_[grab|put]_journal_head

Patch series "ocfs2: fix a deadlock case".

This fixes a deadlock case in ocfs2. We firstly export jbd2 symbols jbd2_journal_[grab|put]_journal_head as preparation and later use them in ocfs2 insread of jbd_[lock|unlock]_bh_journal_head to fix the deadlock.

This patch (of 2):

This exports symbols jbd2_journal_[grab|put]_journal_head, which will be used outside modules, e.g. ocfs2.

Link: https://lkml.kernel.org/r/20220121071205.100648-2-joseph.qi@linux.alibaba.co... Signed-off-by: Joseph Qi joseph.qi@linux.alibaba.com Cc: Mark Fasheh mark@fasheh.com Cc: Joel Becker jlbec@evilplan.org Cc: Junxiao Bi junxiao.bi@oracle.com Cc: Changwei Ge gechangwei@live.cn Cc: Gang He ghe@suse.com Cc: Jun Piao piaojun@huawei.com Cc: Andreas Dilger adilger.kernel@dilger.ca Cc: Gautham Ananthakrishna gautham.ananthakrishna@oracle.com Cc: Saeed Mirzamohammadi saeed.mirzamohammadi@oracle.com Cc: "Theodore Ts'o" tytso@mit.edu Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

fs/jbd2/journal.c | 2 ++ 1 file changed, 2 insertions(+)

--- a/fs/jbd2/journal.c~jbd2-export-jbd2_journal__journal_head +++ a/fs/jbd2/journal.c @@ -2972,6 +2972,7 @@ struct journal_head *jbd2_journal_grab_j jbd_unlock_bh_journal_head(bh); return jh; } +EXPORT_SYMBOL(jbd2_journal_grab_journal_head);

static void __journal_remove_journal_head(struct buffer_head *bh) { @@ -3024,6 +3025,7 @@ void jbd2_journal_put_journal_head(struc jbd_unlock_bh_journal_head(bh); } } +EXPORT_SYMBOL(jbd2_journal_put_journal_head);

/* * Initialize jbd inode head _