jbd2: simplify code flow in do_get_write_access()
needs_copy is set only in one place in do_get_write_access(), just move
the frozen buffer copying into that place and factor it out to a
separate function to make do_get_write_access() slightly more readable.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 799242c..2bcb43d 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -755,6 +755,30 @@
bdevname(bh->b_bdev, b), (unsigned long long)bh->b_blocknr);
}
+/* Call t_frozen trigger and copy buffer data into jh->b_frozen_data. */
+static void jbd2_freeze_jh_data(struct journal_head *jh)
+{
+ struct page *page;
+ int offset;
+ char *source;
+ struct buffer_head *bh = jh2bh(jh);
+
+ J_EXPECT_JH(jh, buffer_uptodate(bh), "Possible IO failure.\n");
+ page = bh->b_page;
+ offset = offset_in_page(bh->b_data);
+ source = kmap_atomic(page);
+ /* Fire data frozen trigger just before we copy the data */
+ jbd2_buffer_frozen_trigger(jh, source + offset, jh->b_triggers);
+ memcpy(jh->b_frozen_data, source + offset, bh->b_size);
+ kunmap_atomic(source);
+
+ /*
+ * Now that the frozen data is saved off, we need to store any matching
+ * triggers.
+ */
+ jh->b_frozen_triggers = jh->b_triggers;
+}
+
/*
* If the buffer is already part of the current transaction, then there
* is nothing we need to do. If it is already part of a prior
@@ -774,7 +798,6 @@
journal_t *journal;
int error;
char *frozen_buffer = NULL;
- int need_copy = 0;
unsigned long start_lock, time_lock;
if (is_handle_aborted(handle))
@@ -931,7 +954,7 @@
}
jh->b_frozen_data = frozen_buffer;
frozen_buffer = NULL;
- need_copy = 1;
+ jbd2_freeze_jh_data(jh);
}
jh->b_next_transaction = transaction;
}
@@ -952,28 +975,6 @@
}
done:
- if (need_copy) {
- struct page *page;
- int offset;
- char *source;
-
- J_EXPECT_JH(jh, buffer_uptodate(jh2bh(jh)),
- "Possible IO failure.\n");
- page = jh2bh(jh)->b_page;
- offset = offset_in_page(jh2bh(jh)->b_data);
- source = kmap_atomic(page);
- /* Fire data frozen trigger just before we copy the data */
- jbd2_buffer_frozen_trigger(jh, source + offset,
- jh->b_triggers);
- memcpy(jh->b_frozen_data, source+offset, jh2bh(jh)->b_size);
- kunmap_atomic(source);
-
- /*
- * Now that the frozen data is saved off, we need to store
- * any matching triggers.
- */
- jh->b_frozen_triggers = jh->b_triggers;
- }
jbd_unlock_bh_state(bh);
/*