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Diffstat (limited to 'drivers/md/dm-table.c')
-rw-r--r--drivers/md/dm-table.c86
1 files changed, 50 insertions, 36 deletions
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 5f59f1e3e5b1..f9c6cb8dbcf8 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -1386,6 +1386,14 @@ static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev,
return q && !blk_queue_add_random(q);
}
+static int queue_supports_sg_merge(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && !test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags);
+}
+
static bool dm_table_all_devices_attribute(struct dm_table *t,
iterate_devices_callout_fn func)
{
@@ -1430,6 +1438,43 @@ static bool dm_table_supports_write_same(struct dm_table *t)
return true;
}
+static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, sector_t len, void *data)
+{
+ struct request_queue *q = bdev_get_queue(dev->bdev);
+
+ return q && blk_queue_discard(q);
+}
+
+static bool dm_table_supports_discards(struct dm_table *t)
+{
+ struct dm_target *ti;
+ unsigned i = 0;
+
+ /*
+ * Unless any target used by the table set discards_supported,
+ * require at least one underlying device to support discards.
+ * t->devices includes internal dm devices such as mirror logs
+ * so we need to use iterate_devices here, which targets
+ * supporting discard selectively must provide.
+ */
+ while (i < dm_table_get_num_targets(t)) {
+ ti = dm_table_get_target(t, i++);
+
+ if (!ti->num_discard_bios)
+ continue;
+
+ if (ti->discards_supported)
+ return 1;
+
+ if (ti->type->iterate_devices &&
+ ti->type->iterate_devices(ti, device_discard_capable, NULL))
+ return 1;
+ }
+
+ return 0;
+}
+
void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
struct queue_limits *limits)
{
@@ -1464,6 +1509,11 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
if (!dm_table_supports_write_same(t))
q->limits.max_write_same_sectors = 0;
+ if (dm_table_all_devices_attribute(t, queue_supports_sg_merge))
+ queue_flag_clear_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
+ else
+ queue_flag_set_unlocked(QUEUE_FLAG_NO_SG_MERGE, q);
+
dm_table_set_integrity(t);
/*
@@ -1636,39 +1686,3 @@ void dm_table_run_md_queue_async(struct dm_table *t)
}
EXPORT_SYMBOL(dm_table_run_md_queue_async);
-static int device_discard_capable(struct dm_target *ti, struct dm_dev *dev,
- sector_t start, sector_t len, void *data)
-{
- struct request_queue *q = bdev_get_queue(dev->bdev);
-
- return q && blk_queue_discard(q);
-}
-
-bool dm_table_supports_discards(struct dm_table *t)
-{
- struct dm_target *ti;
- unsigned i = 0;
-
- /*
- * Unless any target used by the table set discards_supported,
- * require at least one underlying device to support discards.
- * t->devices includes internal dm devices such as mirror logs
- * so we need to use iterate_devices here, which targets
- * supporting discard selectively must provide.
- */
- while (i < dm_table_get_num_targets(t)) {
- ti = dm_table_get_target(t, i++);
-
- if (!ti->num_discard_bios)
- continue;
-
- if (ti->discards_supported)
- return 1;
-
- if (ti->type->iterate_devices &&
- ti->type->iterate_devices(ti, device_discard_capable, NULL))
- return 1;
- }
-
- return 0;
-}