blk-mq: add support for carrying internal tag information in blk_qc_t
No functional change in this patch, just in preparation for having
two types of tags available to the block layer for a single request.
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
diff --git a/block/blk-mq.c b/block/blk-mq.c
index fcdeadc..d40be64 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1308,6 +1308,11 @@
return rq;
}
+static blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq)
+{
+ return blk_tag_to_qc_t(rq->tag, hctx->queue_num, false);
+}
+
static void blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie)
{
int ret;
@@ -1318,7 +1323,7 @@
.list = NULL,
.last = 1
};
- blk_qc_t new_cookie = blk_tag_to_qc_t(rq->tag, hctx->queue_num);
+ blk_qc_t new_cookie = request_to_qc_t(hctx, rq);
if (blk_mq_hctx_stopped(hctx))
goto insert;
@@ -1387,7 +1392,7 @@
wbt_track(&rq->issue_stat, wb_acct);
- cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num);
+ cookie = request_to_qc_t(data.hctx, rq);
if (unlikely(is_flush_fua)) {
blk_mq_bio_to_request(rq, bio);
@@ -1496,7 +1501,7 @@
wbt_track(&rq->issue_stat, wb_acct);
- cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num);
+ cookie = request_to_qc_t(data.hctx, rq);
if (unlikely(is_flush_fua)) {
blk_mq_bio_to_request(rq, bio);
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 519ea2c..0e5b1cd 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -232,22 +232,29 @@
}
typedef unsigned int blk_qc_t;
-#define BLK_QC_T_NONE -1U
-#define BLK_QC_T_SHIFT 16
+#define BLK_QC_T_NONE -1U
+#define BLK_QC_T_SHIFT 16
+#define BLK_QC_T_INTERNAL (1U << 31)
static inline bool blk_qc_t_valid(blk_qc_t cookie)
{
return cookie != BLK_QC_T_NONE;
}
-static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num)
+static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
+ bool internal)
{
- return tag | (queue_num << BLK_QC_T_SHIFT);
+ blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);
+
+ if (internal)
+ ret |= BLK_QC_T_INTERNAL;
+
+ return ret;
}
static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
{
- return cookie >> BLK_QC_T_SHIFT;
+ return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
}
static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
@@ -255,6 +262,11 @@
return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
}
+static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
+{
+ return (cookie & BLK_QC_T_INTERNAL) != 0;
+}
+
struct blk_issue_stat {
u64 time;
};