From 96c3fd1f3802371610c620cff03f9d825707e80e Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Fri, 23 Dec 2011 10:17:54 +1100 Subject: [PATCH] md/raid10: change read_balance to return an rdev It makes more sense to return an rdev than just an index as read_balance() gets a reference to the rdev and so returning the pointer make this more idiomatic. This will be needed in a future patch when we might return a 'replacement' rdev instead of the main rdev. Signed-off-by: NeilBrown --- drivers/md/raid10.c | 27 +++++++++++++-------------- 1 file changed, 13 insertions(+), 14 deletions(-) diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 9722065022fa..70356c130273 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -590,7 +590,9 @@ static int raid10_mergeable_bvec(struct request_queue *q, * FIXME: possibly should rethink readbalancing and do it differently * depending on near_copies / far_copies geometry. */ -static int read_balance(struct r10conf *conf, struct r10bio *r10_bio, int *max_sectors) +static struct md_rdev *read_balance(struct r10conf *conf, + struct r10bio *r10_bio, + int *max_sectors) { const sector_t this_sector = r10_bio->sector; int disk, slot; @@ -703,11 +705,11 @@ retry: } r10_bio->read_slot = slot; } else - disk = -1; + rdev = NULL; rcu_read_unlock(); *max_sectors = best_good_sectors; - return disk; + return rdev; } static int raid10_congested(void *data, int bits) @@ -874,7 +876,6 @@ static void unfreeze_array(struct r10conf *conf) static void make_request(struct mddev *mddev, struct bio * bio) { struct r10conf *conf = mddev->private; - struct mirror_info *mirror; struct r10bio *r10_bio; struct bio *read_bio; int i; @@ -973,17 +974,16 @@ static void make_request(struct mddev *mddev, struct bio * bio) /* * read balancing logic: */ - int disk; + struct md_rdev *rdev; int slot; read_again: - disk = read_balance(conf, r10_bio, &max_sectors); - slot = r10_bio->read_slot; - if (disk < 0) { + rdev = read_balance(conf, r10_bio, &max_sectors); + if (!rdev) { raid_end_bio_io(r10_bio); return; } - mirror = conf->mirrors + disk; + slot = r10_bio->read_slot; read_bio = bio_clone_mddev(bio, GFP_NOIO, mddev); md_trim_bio(read_bio, r10_bio->sector - bio->bi_sector, @@ -992,8 +992,8 @@ read_again: r10_bio->devs[slot].bio = read_bio; read_bio->bi_sector = r10_bio->devs[slot].addr + - mirror->rdev->data_offset; - read_bio->bi_bdev = mirror->rdev->bdev; + rdev->data_offset; + read_bio->bi_bdev = rdev->bdev; read_bio->bi_end_io = raid10_end_read_request; read_bio->bi_rw = READ | do_sync; read_bio->bi_private = r10_bio; @@ -2116,8 +2116,8 @@ static void handle_read_error(struct mddev *mddev, struct r10bio *r10_bio) r10_bio->devs[slot].bio = mddev->ro ? IO_BLOCKED : NULL; read_more: - mirror = read_balance(conf, r10_bio, &max_sectors); - if (mirror == -1) { + rdev = read_balance(conf, r10_bio, &max_sectors); + if (rdev == NULL) { printk(KERN_ALERT "md/raid10:%s: %s: unrecoverable I/O" " read error for block %llu\n", mdname(mddev), b, @@ -2131,7 +2131,6 @@ read_more: if (bio) bio_put(bio); slot = r10_bio->read_slot; - rdev = conf->mirrors[mirror].rdev; printk_ratelimited( KERN_ERR "md/raid10:%s: %s: redirecting" -- 2.11.0