arm64: dts: rk3399-sapphire: add tc358749x device

[firefly-linux-kernel-4.4.55.git] / block / blk-tag.c

diff --git a/block/blk-tag.c b/block/blk-tag.c
index 0c51b4b34f478b0d47460f954542c8ab643ba9eb..f0344e6939d537ecaac05c21a0542c46d37d2808 100644 (file)
--- a/block/blk-tag.c
+++ b/block/blk-tag.c
@@ -119,7 +119,7 @@ fail:
 }
 
 static struct blk_queue_tag *__blk_queue_init_tags(struct request_queue *q,
-                                                  int depth)
+                                               int depth, int alloc_policy)
 {
        struct blk_queue_tag *tags;
 
@@ -131,6 +131,8 @@ static struct blk_queue_tag *__blk_queue_init_tags(struct request_queue *q,
                goto fail;
 
        atomic_set(&tags->refcnt, 1);
+       tags->alloc_policy = alloc_policy;
+       tags->next_tag = 0;
        return tags;
 fail:
        kfree(tags);
@@ -140,10 +142,11 @@ fail:
 /**
  * blk_init_tags - initialize the tag info for an external tag map
  * @depth:     the maximum queue depth supported
+ * @alloc_policy: tag allocation policy
  **/
-struct blk_queue_tag *blk_init_tags(int depth)
+struct blk_queue_tag *blk_init_tags(int depth, int alloc_policy)
 {
-       return __blk_queue_init_tags(NULL, depth);
+       return __blk_queue_init_tags(NULL, depth, alloc_policy);
 }
 EXPORT_SYMBOL(blk_init_tags);
 
@@ -152,19 +155,20 @@ EXPORT_SYMBOL(blk_init_tags);
  * @q:  the request queue for the device
  * @depth:  the maximum queue depth supported
  * @tags: the tag to use
+ * @alloc_policy: tag allocation policy
  *
  * Queue lock must be held here if the function is called to resize an
  * existing map.
  **/
 int blk_queue_init_tags(struct request_queue *q, int depth,
-                       struct blk_queue_tag *tags)
+                       struct blk_queue_tag *tags, int alloc_policy)
 {
        int rc;
 
        BUG_ON(tags && q->queue_tags && tags != q->queue_tags);
 
        if (!tags && !q->queue_tags) {
-               tags = __blk_queue_init_tags(q, depth);
+               tags = __blk_queue_init_tags(q, depth, alloc_policy);
 
                if (!tags)
                        return -ENOMEM;
@@ -329,17 +333,36 @@ int blk_queue_start_tag(struct request_queue *q, struct request *rq)
         */
        max_depth = bqt->max_depth;
        if (!rq_is_sync(rq) && max_depth > 1) {
-               max_depth -= 2;
-               if (!max_depth)
+               switch (max_depth) {
+               case 2:
                        max_depth = 1;
+                       break;
+               case 3:
+                       max_depth = 2;
+                       break;
+               default:
+                       max_depth -= 2;
+               }
                if (q->in_flight[BLK_RW_ASYNC] > max_depth)
                        return 1;
        }
 
        do {
-               tag = find_first_zero_bit(bqt->tag_map, max_depth);
-               if (tag >= max_depth)
-                       return 1;
+               if (bqt->alloc_policy == BLK_TAG_ALLOC_FIFO) {
+                       tag = find_first_zero_bit(bqt->tag_map, max_depth);
+                       if (tag >= max_depth)
+                               return 1;
+               } else {
+                       int start = bqt->next_tag;
+                       int size = min_t(int, bqt->max_depth, max_depth + start);
+                       tag = find_next_zero_bit(bqt->tag_map, size, start);
+                       if (tag >= size && start + size > bqt->max_depth) {
+                               size = start + size - bqt->max_depth;
+                               tag = find_first_zero_bit(bqt->tag_map, size);
+                       }
+                       if (tag >= size)
+                               return 1;
+               }
 
        } while (test_and_set_bit_lock(tag, bqt->tag_map));
        /*
@@ -347,6 +370,7 @@ int blk_queue_start_tag(struct request_queue *q, struct request *rq)
         * See blk_queue_end_tag for details.
         */
 
+       bqt->next_tag = (tag + 1) % bqt->max_depth;
        rq->cmd_flags |= REQ_QUEUED;
        rq->tag = tag;
        bqt->tag_index[tag] = rq;