X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=drivers%2Fmd%2Fdm-table.c;h=90267f8d64eeadf5d9e72afae174f6d4b22e6bf5;hb=e9dd2b6837e26fe202708cce5ea4bb4ee3e3482e;hp=9924ea23032d6f7418f15f1f8b4198b5c5dedd88;hpb=6fe70aae0d128339febfabc073ba4c4a03de4f45;p=karo-tx-linux.git

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 9924ea23032d..90267f8d64ee 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -54,6 +54,8 @@ struct dm_table {
 	sector_t *highs;
 	struct dm_target *targets;
 
+	unsigned discards_supported:1;
+
 	/*
 	 * Indicates the rw permissions for the new logical
 	 * device.  This should be a combination of FMODE_READ
@@ -203,6 +205,7 @@ int dm_table_create(struct dm_table **result, fmode_t mode,
 
 	INIT_LIST_HEAD(&t->devices);
 	atomic_set(&t->holders, 0);
+	t->discards_supported = 1;
 
 	if (!num_targets)
 		num_targets = KEYS_PER_NODE;
@@ -245,7 +248,7 @@ void dm_table_destroy(struct dm_table *t)
 		msleep(1);
 	smp_mb();
 
-	/* free the indexes (see dm_table_complete) */
+	/* free the indexes */
 	if (t->depth >= 2)
 		vfree(t->index[t->depth - 2]);
 
@@ -483,11 +486,6 @@ static int __table_get_device(struct dm_table *t, struct dm_target *ti,
 	return 0;
 }
 
-/*
- * Returns the minimum that is _not_ zero, unless both are zero.
- */
-#define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
-
 int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
 			 sector_t start, sector_t len, void *data)
 {
@@ -770,6 +768,9 @@ int dm_table_add_target(struct dm_table *t, const char *type,
 
 	t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
 
+	if (!tgt->num_discard_requests)
+		t->discards_supported = 0;
+
 	return 0;
 
  bad:
@@ -778,7 +779,7 @@ int dm_table_add_target(struct dm_table *t, const char *type,
 	return r;
 }
 
-int dm_table_set_type(struct dm_table *t)
+static int dm_table_set_type(struct dm_table *t)
 {
 	unsigned i;
 	unsigned bio_based = 0, request_based = 0;
@@ -900,7 +901,7 @@ static int setup_indexes(struct dm_table *t)
 /*
  * Builds the btree to index the map.
  */
-int dm_table_complete(struct dm_table *t)
+static int dm_table_build_index(struct dm_table *t)
 {
 	int r = 0;
 	unsigned int leaf_nodes;
@@ -919,6 +920,55 @@ int dm_table_complete(struct dm_table *t)
 	return r;
 }
 
+/*
+ * Register the mapped device for blk_integrity support if
+ * the underlying devices support it.
+ */
+static int dm_table_prealloc_integrity(struct dm_table *t, struct mapped_device *md)
+{
+	struct list_head *devices = dm_table_get_devices(t);
+	struct dm_dev_internal *dd;
+
+	list_for_each_entry(dd, devices, list)
+		if (bdev_get_integrity(dd->dm_dev.bdev))
+			return blk_integrity_register(dm_disk(md), NULL);
+
+	return 0;
+}
+
+/*
+ * Prepares the table for use by building the indices,
+ * setting the type, and allocating mempools.
+ */
+int dm_table_complete(struct dm_table *t)
+{
+	int r;
+
+	r = dm_table_set_type(t);
+	if (r) {
+		DMERR("unable to set table type");
+		return r;
+	}
+
+	r = dm_table_build_index(t);
+	if (r) {
+		DMERR("unable to build btrees");
+		return r;
+	}
+
+	r = dm_table_prealloc_integrity(t, t->md);
+	if (r) {
+		DMERR("could not register integrity profile.");
+		return r;
+	}
+
+	r = dm_table_alloc_md_mempools(t);
+	if (r)
+		DMERR("unable to allocate mempools");
+
+	return r;
+}
+
 static DEFINE_MUTEX(_event_lock);
 void dm_table_event_callback(struct dm_table *t,
 			     void (*fn)(void *), void *context)
@@ -1086,6 +1136,11 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
 	else
 		queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, q);
 
+	if (!dm_table_supports_discards(t))
+		queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD, q);
+	else
+		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
+
 	dm_table_set_integrity(t);
 
 	/*
@@ -1232,6 +1287,39 @@ struct mapped_device *dm_table_get_md(struct dm_table *t)
 	return t->md;
 }
 
+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;
+
+	if (!t->discards_supported)
+		return 0;
+
+	/*
+	 * Ensure that at least one underlying device supports discards.
+	 * t->devices includes internal dm devices such as mirror logs
+	 * so we need to use iterate_devices here, which targets
+	 * supporting discard must provide.
+	 */
+	while (i < dm_table_get_num_targets(t)) {
+		ti = dm_table_get_target(t, i++);
+
+		if (ti->type->iterate_devices &&
+		    ti->type->iterate_devices(ti, device_discard_capable, NULL))
+			return 1;
+	}
+
+	return 0;
+}
+
 EXPORT_SYMBOL(dm_vcalloc);
 EXPORT_SYMBOL(dm_get_device);
 EXPORT_SYMBOL(dm_put_device);