dm-raid456 does not provide a 'queue' for raid5 to use, so we must make raid5 stop depending on the queue. First: read_ahead dm handles read-ahead adjustment fully in userspace, so simply don't do any readahead adjustments if there is no queue. Also re-arrange code slightly so all the accesses to ->queue are together. Finally, move the blk_queue_merge_bvec function into the 'if' as the ->split_io setting in dm-raid456 has the same effect. Signed-off-by: NeilBrown <neilb@xxxxxxx> --- drivers/md/raid5.c | 32 +++++++++++++++++--------------- 1 files changed, 17 insertions(+), 15 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 74e36a2..8839573 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5072,16 +5072,6 @@ static int run(mddev_t *mddev) "reshape"); } - /* read-ahead size must cover two whole stripes, which is - * 2 * (datadisks) * chunksize where 'n' is the number of raid devices - */ - { - int data_disks = conf->previous_raid_disks - conf->max_degraded; - int stripe = data_disks * - ((mddev->chunk_sectors << 9) / PAGE_SIZE); - if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) - mddev->queue->backing_dev_info.ra_pages = 2 * stripe; - } /* Ok, everything is just fine now */ if (mddev->to_remove == &raid5_attrs_group) @@ -5089,8 +5079,23 @@ static int run(mddev_t *mddev) else if (mddev->kobj.sd && sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) printk(KERN_WARNING - "md/raid:%s: failed to create sysfs attributes.\n", + "raid5: failed to create sysfs attributes for %s\n", mdname(mddev)); + md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); + + if (mddev->queue) { + /* read-ahead size must cover two whole stripes, which + * is 2 * (datadisks) * chunksize where 'n' is the + * number of raid devices + */ + int data_disks = conf->previous_raid_disks - conf->max_degraded; + int stripe = data_disks * + ((mddev->chunk_sectors << 9) / PAGE_SIZE); + if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) + mddev->queue->backing_dev_info.ra_pages = 2 * stripe; + + blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); + } mddev->queue->queue_lock = &conf->device_lock; @@ -5098,9 +5103,6 @@ static int run(mddev_t *mddev) mddev->queue->backing_dev_info.congested_data = mddev; mddev->queue->backing_dev_info.congested_fn = raid5_congested; - md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); - - blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); chunk_size = mddev->chunk_sectors << 9; blk_queue_io_min(mddev->queue, chunk_size); blk_queue_io_opt(mddev->queue, chunk_size * @@ -5523,7 +5525,7 @@ static void end_reshape(raid5_conf_t *conf) /* read-ahead size must cover two whole stripes, which is * 2 * (datadisks) * chunksize where 'n' is the number of raid devices */ - { + if (conf->mddev->queue) { int data_disks = conf->raid_disks - conf->max_degraded; int stripe = data_disks * ((conf->chunk_sectors << 9) / PAGE_SIZE); -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel