ext4: Use WRITE_SYNC for commits which are caused by fsync()
If a commit is triggered by fsync(), set a flag indicating the journal
blocks associated with the transaction should be flushed out using
WRITE_SYNC.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c
index 62804e5..4ea7237 100644
--- a/fs/jbd2/commit.c
+++ b/fs/jbd2/commit.c
@@ -367,6 +367,7 @@
int tag_bytes = journal_tag_bytes(journal);
struct buffer_head *cbh = NULL; /* For transactional checksums */
__u32 crc32_sum = ~0;
+ int write_op = WRITE;
/*
* First job: lock down the current transaction and wait for
@@ -401,6 +402,8 @@
spin_lock(&journal->j_state_lock);
commit_transaction->t_state = T_LOCKED;
+ if (commit_transaction->t_synchronous_commit)
+ write_op = WRITE_SYNC;
stats.u.run.rs_wait = commit_transaction->t_max_wait;
stats.u.run.rs_locked = jiffies;
stats.u.run.rs_running = jbd2_time_diff(commit_transaction->t_start,
@@ -680,7 +683,7 @@
clear_buffer_dirty(bh);
set_buffer_uptodate(bh);
bh->b_end_io = journal_end_buffer_io_sync;
- submit_bh(WRITE, bh);
+ submit_bh(write_op, bh);
}
cond_resched();
stats.u.run.rs_blocks_logged += bufs;
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 28ce21d..996ffda 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1315,6 +1315,8 @@
}
}
+ if (handle->h_sync)
+ transaction->t_synchronous_commit = 1;
current->journal_info = NULL;
spin_lock(&journal->j_state_lock);
spin_lock(&transaction->t_handle_lock);
diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 4d248b3..8815a34 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -649,6 +649,12 @@
int t_handle_count;
/*
+ * This transaction is being forced and some process is
+ * waiting for it to finish.
+ */
+ int t_synchronous_commit:1;
+
+ /*
* For use by the filesystem to store fs-specific data
* structures associated with the transaction
*/