[RFC PATCH 17/28] block: Introduce queue flag to indicate support for dma-direct bios

Logan Gunthorpe
2019-06-20T16:12:29Z

Queues will need to advertise support to accept dma-direct requests.

The existing PCI P2P support which will be replaced by this and thus
the P2P flag will be dropped in a subsequent patch.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
---
include/linux/blkdev.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index ce70d5dded5f..a5b856324276 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -616,6 +616,7 @@ struct request_queue {
#define QUEUE_FLAG_SCSI_PASSTHROUGH 23 /* queue supports SCSI commands */
#define QUEUE_FLAG_QUIESCED 24 /* queue has been quiesced */
#define QUEUE_FLAG_PCI_P2PDMA 25 /* device supports PCI p2p requests */
+#define QUEUE_FLAG_DMA_DIRECT 26 /* device supports dma-addr requests */

#define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
(1 << QUEUE_FLAG_SAME_COMP))
@@ -642,6 +643,8 @@ bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q);
test_bit(QUEUE_FLAG_SCSI_PASSTHROUGH, &(q)->queue_flags)
#define blk_queue_pci_p2pdma(q) \
test_bit(QUEUE_FLAG_PCI_P2PDMA, &(q)->queue_flags)
+#define blk_queue_dma_direct(q) \
+ test_bit(QUEUE_FLAG_DMA_DIRECT, &(q)->queue_flags)

#define blk_noretry_request(rq) \
((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
--
2.20.1