From: Miquel van Smoorenburg <miquels@cistron.nl>
This implements the queue congestion callout for DM stacks. To make
bdi_read/write_congested() return correct information.
---
25-akpm/drivers/md/dm-table.c | 14 ++++++++++++++
25-akpm/drivers/md/dm.c | 14 ++++++++++++++
25-akpm/drivers/md/dm.h | 1 +
3 files changed, 29 insertions(+)
diff -puN drivers/md/dm.c~queue-congestion-dm-implementation drivers/md/dm.c
--- 25/drivers/md/dm.c~queue-congestion-dm-implementation Thu Feb 26 14:24:11 2004
+++ 25-akpm/drivers/md/dm.c Thu Feb 26 14:24:11 2004
@@ -489,6 +489,18 @@ static int dm_request(request_queue_t *q
return 0;
}
+static int dm_any_congested(void *congested_data, int bdi_bits)
+{
+ int r;
+ struct mapped_device *md = congested_data;
+
+ down_read(&md->lock);
+ r = dm_table_any_congested(md->map, bdi_bits);
+ up_read(&md->lock);
+
+ return r;
+}
+
/*-----------------------------------------------------------------
* A bitset is used to keep track of allocated minor numbers.
*---------------------------------------------------------------*/
@@ -567,6 +579,8 @@ static struct mapped_device *alloc_dev(u
goto bad1;
md->queue->queuedata = md;
+ md->queue->backing_dev_info.congested_fn = dm_any_congested;
+ md->queue->backing_dev_info.congested_data = md;
blk_queue_make_request(md->queue, dm_request);
md->io_pool = mempool_create(MIN_IOS, mempool_alloc_slab,
diff -puN drivers/md/dm.h~queue-congestion-dm-implementation drivers/md/dm.h
--- 25/drivers/md/dm.h~queue-congestion-dm-implementation Thu Feb 26 14:24:11 2004
+++ 25-akpm/drivers/md/dm.h Thu Feb 26 14:24:11 2004
@@ -115,6 +115,7 @@ struct list_head *dm_table_get_devices(s
int dm_table_get_mode(struct dm_table *t);
void dm_table_suspend_targets(struct dm_table *t);
void dm_table_resume_targets(struct dm_table *t);
+int dm_table_any_congested(struct dm_table *t, int bdi_bits);
/*-----------------------------------------------------------------
* A registry of target types.
diff -puN drivers/md/dm-table.c~queue-congestion-dm-implementation drivers/md/dm-table.c
--- 25/drivers/md/dm-table.c~queue-congestion-dm-implementation Thu Feb 26 14:24:11 2004
+++ 25-akpm/drivers/md/dm-table.c Thu Feb 26 14:24:11 2004
@@ -862,6 +862,20 @@ void dm_table_resume_targets(struct dm_t
}
}
+int dm_table_any_congested(struct dm_table *t, int bdi_bits)
+{
+ struct list_head *d, *devices;
+ int r = 0;
+
+ devices = dm_table_get_devices(t);
+ for (d = devices->next; d != devices; d = d->next) {
+ struct dm_dev *dd = list_entry(d, struct dm_dev, list);
+ request_queue_t *q = bdev_get_queue(dd->bdev);
+ r |= bdi_congested(&q->backing_dev_info, bdi_bits);
+ }
+
+ return r;
+}
EXPORT_SYMBOL(dm_vcalloc);
EXPORT_SYMBOL(dm_get_device);
_