Merge branch 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied...

[pandora-kernel.git] / drivers / md / dm-table.c

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 9924ea2..f9fc07d 100644 (file)
--- 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]);
 
@@ -770,6 +773,9 @@ 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 +784,7 @@ 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 +906,7 @@ 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 +925,55 @@ 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 +1141,11 @@ 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 +1292,39 @@ 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);