diff options
| -rw-r--r-- | drivers/md/md.c | 79 | ||||
| -rw-r--r-- | drivers/md/md.h | 2 | ||||
| -rw-r--r-- | drivers/md/raid1.c | 3 | ||||
| -rw-r--r-- | drivers/md/raid10.c | 3 |
4 files changed, 72 insertions, 15 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index f30f09c..6cb31f8 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -201,12 +201,68 @@ static DEFINE_SPINLOCK(all_mddevs_lock); ) -static int md_fail_request(struct request_queue *q, struct bio *bio) +/* Rather than calling directly into the personality make_request function, + * IO requests come here first so that we can check if the device is + * being suspended pending a reconfiguration. + * We hold a refcount over the call to ->make_request. By the time that + * call has finished, the bio has been linked into some internal structure + * and so is visible to ->quiesce(), so we don't need the refcount any more. + */ +static int md_make_request(struct request_queue *q, struct bio *bio) { - bio_io_error(bio); - return 0; + mddev_t *mddev = q->queuedata; + int rv; + if (mddev == NULL || mddev->pers == NULL) { + bio_io_error(bio); + return 0; + } + rcu_read_lock(); + if (mddev->suspended) { + DEFINE_WAIT(__wait); + for (;;) { + prepare_to_wait(&mddev->sb_wait, &__wait, + TASK_UNINTERRUPTIBLE); + if (!mddev->suspended) + break; + rcu_read_unlock(); + schedule(); + rcu_read_lock(); + } + finish_wait(&mddev->sb_wait, &__wait); + } + atomic_inc(&mddev->active_io); + rcu_read_unlock(); + rv = mddev->pers->make_request(q, bio); + if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended) + wake_up(&mddev->sb_wait); + + return rv; } +static void mddev_suspend(mddev_t *mddev) +{ + BUG_ON(mddev->suspended); + mddev->suspended = 1; + synchronize_rcu(); + wait_event(mddev->sb_wait, atomic_read(&mddev->active_io) == 0); + mddev->pers->quiesce(mddev, 1); + md_unregister_thread(mddev->thread); + mddev->thread = NULL; + /* we now know that no code is executing in the personality module, + * except possibly the tail end of a ->bi_end_io function, but that + * is certain to complete before the module has a chance to get + * unloaded + */ +} + +static void mddev_resume(mddev_t *mddev) +{ + mddev->suspended = 0; + wake_up(&mddev->sb_wait); + mddev->pers->quiesce(mddev, 0); +} + + static inline mddev_t *mddev_get(mddev_t *mddev) { atomic_inc(&mddev->active); @@ -314,6 +370,7 @@ static mddev_t * mddev_find(dev_t unit) init_timer(&new->safemode_timer); atomic_set(&new->active, 1); atomic_set(&new->openers, 0); + atomic_set(&new->active_io, 0); spin_lock_init(&new->write_lock); init_waitqueue_head(&new->sb_wait); init_waitqueue_head(&new->recovery_wait); @@ -3632,10 +3689,12 @@ static int md_alloc(dev_t dev, char *name) mddev_put(mddev); return -ENOMEM; } + mddev->queue->queuedata = mddev; + /* Can be unlocked because the queue is new: no concurrency */ queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, mddev->queue); - blk_queue_make_request(mddev->queue, md_fail_request); + blk_queue_make_request(mddev->queue, md_make_request); disk = alloc_disk(1 << shift); if (!disk) { @@ -3938,16 +3997,6 @@ static int do_md_run(mddev_t * mddev) set_capacity(disk, mddev->array_sectors); - /* If we call blk_queue_make_request here, it will - * re-initialise max_sectors etc which may have been - * refined inside -> run. So just set the bits we need to set. - * Most initialisation happended when we called - * blk_queue_make_request(..., md_fail_request) - * earlier. - */ - mddev->queue->queuedata = mddev; - mddev->queue->make_request_fn = mddev->pers->make_request; - /* If there is a partially-recovered drive we need to * start recovery here. If we leave it to md_check_recovery, * it will remove the drives and not do the right thing @@ -4077,7 +4126,7 @@ static int do_md_stop(mddev_t * mddev, int mode, int is_open) md_super_wait(mddev); if (mddev->ro) set_disk_ro(disk, 0); - blk_queue_make_request(mddev->queue, md_fail_request); + mddev->pers->stop(mddev); mddev->queue->merge_bvec_fn = NULL; mddev->queue->unplug_fn = NULL; diff --git a/drivers/md/md.h b/drivers/md/md.h index c07ea91..84b22d6 100644 --- a/drivers/md/md.h +++ b/drivers/md/md.h @@ -119,6 +119,8 @@ struct mddev_s #define MD_CHANGE_CLEAN 1 /* transition to or from 'clean' */ #define MD_CHANGE_PENDING 2 /* superblock update in progress */ + int suspended; + atomic_t active_io; int ro; struct gendisk *gendisk; diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 7799587..7eaca32 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -2092,6 +2092,9 @@ static int stop(mddev_t *mddev) /* need to kick something here to make sure I/O goes? */ } + raise_barrier(conf); + lower_barrier(conf); + md_unregister_thread(mddev->thread); mddev->thread = NULL; blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index d56cb2a..c2059e2 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -2211,6 +2211,9 @@ static int stop(mddev_t *mddev) { conf_t *conf = mddev_to_conf(mddev); + raise_barrier(conf, 0); + lower_barrier(conf); + md_unregister_thread(mddev->thread); mddev->thread = NULL; blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |