From ee57aba159a5c329dc78c181a3ae0549e59f0925 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Mon, 8 Jun 2015 12:39:07 -0400 Subject: [PATCH] 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 Signed-off-by: Theodore Ts'o --- fs/jbd2/transaction.c | 49 ++++++++++++++++++++++--------------------- 1 file changed, 25 insertions(+), 24 deletions(-) diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index 799242cecffb..2bcb43d770a0 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -755,6 +755,30 @@ static void warn_dirty_buffer(struct buffer_head *bh) 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 @@ do_get_write_access(handle_t *handle, struct journal_head *jh, 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 @@ do_get_write_access(handle_t *handle, struct journal_head *jh, } 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 @@ do_get_write_access(handle_t *handle, struct journal_head *jh, } 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); /*