diff options
Diffstat (limited to 'drivers/md/md.c')
| -rw-r--r-- | drivers/md/md.c | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index f877569..eec75f1 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -386,6 +386,51 @@ void md_barrier_request(mddev_t *mddev, struct bio *bio) } EXPORT_SYMBOL(md_barrier_request); +/* Support for plugging. + * This mirrors the plugging support in request_queue, but does not + * require having a whole queue + */ +static void plugger_work(struct work_struct *work) +{ + struct plug_handle *plug = + container_of(work, struct plug_handle, unplug_work); + plug->unplug_fn(plug); +} +static void plugger_timeout(unsigned long data) +{ + struct plug_handle *plug = (void *)data; + kblockd_schedule_work(NULL, &plug->unplug_work); +} +void plugger_init(struct plug_handle *plug, + void (*unplug_fn)(struct plug_handle *)) +{ + plug->unplug_flag = 0; + plug->unplug_fn = unplug_fn; + init_timer(&plug->unplug_timer); + plug->unplug_timer.function = plugger_timeout; + plug->unplug_timer.data = (unsigned long)plug; + INIT_WORK(&plug->unplug_work, plugger_work); +} +EXPORT_SYMBOL_GPL(plugger_init); + +void plugger_set_plug(struct plug_handle *plug) +{ + if (!test_and_set_bit(PLUGGED_FLAG, &plug->unplug_flag)) + mod_timer(&plug->unplug_timer, jiffies + msecs_to_jiffies(3)+1); +} +EXPORT_SYMBOL_GPL(plugger_set_plug); + +int plugger_remove_plug(struct plug_handle *plug) +{ + if (test_and_clear_bit(PLUGGED_FLAG, &plug->unplug_flag)) { + del_timer(&plug->unplug_timer); + return 1; + } else + return 0; +} +EXPORT_SYMBOL_GPL(plugger_remove_plug); + + static inline mddev_t *mddev_get(mddev_t *mddev) { atomic_inc(&mddev->active); |