From c1b9919849866b96dc435f025beaa307dc76ca27 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 5 Oct 2015 09:31:14 +0200 Subject: [PATCH] raid5-cache: new helper: r5_reserve_log_entry Factor out code to reserve log space. Signed-off-by: Christoph Hellwig Reviewed-by: Shaohua Li Signed-off-by: NeilBrown --- drivers/md/raid5-cache.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c index 88758285261c..ea20d740a67c 100644 --- a/drivers/md/raid5-cache.c +++ b/drivers/md/raid5-cache.c @@ -271,6 +271,23 @@ static struct bio *r5l_bio_alloc(struct r5l_log *log, struct r5l_io_unit *io) return bio; } +static void r5_reserve_log_entry(struct r5l_log *log, struct r5l_io_unit *io) +{ + log->log_start = r5l_ring_add(log, log->log_start, BLOCK_SECTORS); + + /* + * If we filled up the log device start from the beginning again, + * which will require a new bio. + * + * Note: for this to work properly the log size needs to me a multiple + * of BLOCK_SECTORS. + */ + if (log->log_start == 0) + io->current_bio = NULL; + + io->log_end = log->log_start; +} + static struct r5l_io_unit *r5l_new_meta(struct r5l_log *log) { struct r5l_io_unit *io; @@ -299,11 +316,7 @@ static struct r5l_io_unit *r5l_new_meta(struct r5l_log *log) bio_add_page(io->current_bio, io->meta_page, PAGE_SIZE, 0); log->seq++; - log->log_start = r5l_ring_add(log, log->log_start, BLOCK_SECTORS); - io->log_end = log->log_start; - /* current bio hit disk end */ - if (log->log_start == 0) - io->current_bio = NULL; + r5_reserve_log_entry(log, io); spin_lock_irq(&log->io_list_lock); list_add_tail(&io->log_sibling, &log->running_ios); @@ -357,13 +370,8 @@ alloc_bio: io->current_bio = NULL; goto alloc_bio; } - log->log_start = r5l_ring_add(log, log->log_start, - BLOCK_SECTORS); - /* current bio hit disk end */ - if (log->log_start == 0) - io->current_bio = NULL; - io->log_end = log->log_start; + r5_reserve_log_entry(log, io); } static void r5l_log_stripe(struct r5l_log *log, struct stripe_head *sh, -- 2.39.2