[PATCH 1/4] ext4: fix incorrect tid assumption in ext4_wait_for_tail_page_commit()

Luis Henriques (SUSE)
2024-07-23T15:44:19Z

Function ext4_wait_for_tail_page_commit() assumes that '0' is not a valid
value for transaction IDs, which is incorrect. Don't assume that and invoke
jbd2_log_wait_commit() if the journal had a committing transaction instead.

Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev>
---
fs/ext4/inode.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 941c1c0d5c6e..e65fc2086701 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5279,8 +5279,9 @@ static void ext4_wait_for_tail_page_commit(struct inode *inode)
{
unsigned offset;
journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
- tid_t commit_tid = 0;
+ tid_t commit_tid;
int ret;
+ bool has_transaction = false;

offset = inode->i_size & (PAGE_SIZE - 1);
/*
@@ -5305,12 +5306,13 @@ static void ext4_wait_for_tail_page_commit(struct inode *inode)
folio_put(folio);
if (ret != -EBUSY)
return;
- commit_tid = 0;
read_lock(&journal->j_state_lock);
- if (journal->j_committing_transaction)
+ if (journal->j_committing_transaction) {
commit_tid = journal->j_committing_transaction->t_tid;
+ has_transaction = true;
+ }
read_unlock(&journal->j_state_lock);
- if (commit_tid)
+ if (has_transaction)
jbd2_log_wait_commit(journal, commit_tid);
}
}