dm: remove queue next_ordered workaround for barriers

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

diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 09a5711..5d16d06 100644 (file)
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -41,6 +41,7 @@
 struct dm_table {
        struct mapped_device *md;
        atomic_t holders;
+       unsigned type;
 
        /* btree table */
        unsigned int depth;
@@ -65,6 +66,8 @@ struct dm_table {
        /* events get handed up using this callback */
        void (*event_fn)(void *);
        void *event_context;
+
+       struct dm_md_mempools *mempools;
 };
 
 /*
@@ -258,6 +261,8 @@ void dm_table_destroy(struct dm_table *t)
        if (t->devices.next != &t->devices)
                free_devices(&t->devices);
 
+       dm_free_md_mempools(t->mempools);
+
        kfree(t);
 }
 
@@ -490,7 +495,7 @@ int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
                return 0;
        }
 
-       if (blk_stack_limits(limits, &q->limits, start) < 0)
+       if (blk_stack_limits(limits, &q->limits, start << 9) < 0)
                DMWARN("%s: target device %s is misaligned",
                       dm_device_name(ti->table->md), bdevname(bdev, b));
 
@@ -764,6 +769,99 @@ int dm_table_add_target(struct dm_table *t, const char *type,
        return r;
 }
 
+int dm_table_set_type(struct dm_table *t)
+{
+       unsigned i;
+       unsigned bio_based = 0, request_based = 0;
+       struct dm_target *tgt;
+       struct dm_dev_internal *dd;
+       struct list_head *devices;
+
+       for (i = 0; i < t->num_targets; i++) {
+               tgt = t->targets + i;
+               if (dm_target_request_based(tgt))
+                       request_based = 1;
+               else
+                       bio_based = 1;
+
+               if (bio_based && request_based) {
+                       DMWARN("Inconsistent table: different target types"
+                              " can't be mixed up");
+                       return -EINVAL;
+               }
+       }
+
+       if (bio_based) {
+               /* We must use this table as bio-based */
+               t->type = DM_TYPE_BIO_BASED;
+               return 0;
+       }
+
+       BUG_ON(!request_based); /* No targets in this table */
+
+       /* Non-request-stackable devices can't be used for request-based dm */
+       devices = dm_table_get_devices(t);
+       list_for_each_entry(dd, devices, list) {
+               if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) {
+                       DMWARN("table load rejected: including"
+                              " non-request-stackable devices");
+                       return -EINVAL;
+               }
+       }
+
+       /*
+        * Request-based dm supports only tables that have a single target now.
+        * To support multiple targets, request splitting support is needed,
+        * and that needs lots of changes in the block-layer.
+        * (e.g. request completion process for partial completion.)
+        */
+       if (t->num_targets > 1) {
+               DMWARN("Request-based dm doesn't support multiple targets yet");
+               return -EINVAL;
+       }
+
+       t->type = DM_TYPE_REQUEST_BASED;
+
+       return 0;
+}
+
+unsigned dm_table_get_type(struct dm_table *t)
+{
+       return t->type;
+}
+
+bool dm_table_request_based(struct dm_table *t)
+{
+       return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
+}
+
+int dm_table_alloc_md_mempools(struct dm_table *t)
+{
+       unsigned type = dm_table_get_type(t);
+
+       if (unlikely(type == DM_TYPE_NONE)) {
+               DMWARN("no table type is set, can't allocate mempools");
+               return -EINVAL;
+       }
+
+       t->mempools = dm_alloc_md_mempools(type);
+       if (!t->mempools)
+               return -ENOMEM;
+
+       return 0;
+}
+
+void dm_table_free_md_mempools(struct dm_table *t)
+{
+       dm_free_md_mempools(t->mempools);
+       t->mempools = NULL;
+}
+
+struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
+{
+       return t->mempools;
+}
+
 static int setup_indexes(struct dm_table *t)
 {
        int i;
@@ -985,6 +1083,19 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
                queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, q);
 
        dm_table_set_integrity(t);
+
+       /*
+        * QUEUE_FLAG_STACKABLE must be set after all queue settings are
+        * visible to other CPUs because, once the flag is set, incoming bios
+        * are processed by request-based dm, which refers to the queue
+        * settings.
+        * Until the flag set, bios are passed to bio-based dm and queued to
+        * md->deferred where queue settings are not needed yet.
+        * Those bios are passed to request-based dm at the resume time.
+        */
+       smp_mb();
+       if (dm_table_request_based(t))
+               queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
 }
 
 unsigned int dm_table_get_num_targets(struct dm_table *t)
@@ -1080,6 +1191,20 @@ int dm_table_any_congested(struct dm_table *t, int bdi_bits)
        return r;
 }
 
+int dm_table_any_busy_target(struct dm_table *t)
+{
+       unsigned i;
+       struct dm_target *ti;
+
+       for (i = 0; i < t->num_targets; i++) {
+               ti = t->targets + i;
+               if (ti->type->busy && ti->type->busy(ti))
+                       return 1;
+       }
+
+       return 0;
+}
+
 void dm_table_unplug_all(struct dm_table *t)
 {
        struct dm_dev_internal *dd;