[PATCH blk-next 1/2] blk-mq-rdma: Delete not-used multi-queue RDMA map queue code

[Leon Romanovsky]

From: Leon Romanovsky <leonro at nvidia.com>

The RDMA vector affinity code is not backed up by any driver and always
returns NULL to every ib_get_vector_affinity() call.

This means that blk_mq_rdma_map_queues() always takes fallback path.

Fixes: 9afc97c29b03 ("mlx5: remove support for ib_get_vector_affinity")
Signed-off-by: Leon Romanovsky <leonro at nvidia.com>
---
 block/Kconfig               |  5 -----
 block/Makefile              |  1 -
 block/blk-mq-rdma.c         | 44 -------------------------------------
 drivers/nvme/host/rdma.c    |  7 ++----
 include/linux/blk-mq-rdma.h | 11 ----------
 5 files changed, 2 insertions(+), 66 deletions(-)
 delete mode 100644 block/blk-mq-rdma.c
 delete mode 100644 include/linux/blk-mq-rdma.h

diff --git a/block/Kconfig b/block/Kconfig
index bbad5e8bbffe..8ede308a1343 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -227,11 +227,6 @@ config BLK_MQ_VIRTIO
 	depends on BLOCK && VIRTIO
 	default y

-config BLK_MQ_RDMA
-	bool
-	depends on BLOCK && INFINIBAND
-	default y
-
 config BLK_PM
 	def_bool BLOCK && PM

diff --git a/block/Makefile b/block/Makefile
index 8d841f5f986f..bbdc3e82308a 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -29,7 +29,6 @@ obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o blk-integrity.o
 obj-$(CONFIG_BLK_DEV_INTEGRITY_T10)	+= t10-pi.o
 obj-$(CONFIG_BLK_MQ_PCI)	+= blk-mq-pci.o
 obj-$(CONFIG_BLK_MQ_VIRTIO)	+= blk-mq-virtio.o
-obj-$(CONFIG_BLK_MQ_RDMA)	+= blk-mq-rdma.o
 obj-$(CONFIG_BLK_DEV_ZONED)	+= blk-zoned.o
 obj-$(CONFIG_BLK_WBT)		+= blk-wbt.o
 obj-$(CONFIG_BLK_DEBUG_FS)	+= blk-mq-debugfs.o
diff --git a/block/blk-mq-rdma.c b/block/blk-mq-rdma.c
deleted file mode 100644
index 14f968e58b8f..000000000000
--- a/block/blk-mq-rdma.c
+++ /dev/null
@@ -1,44 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (c) 2017 Sagi Grimberg.
- */
-#include <linux/blk-mq.h>
-#include <linux/blk-mq-rdma.h>
-#include <rdma/ib_verbs.h>
-
-/**
- * blk_mq_rdma_map_queues - provide a default queue mapping for rdma device
- * @map:	CPU to hardware queue map.
- * @dev:	rdma device to provide a mapping for.
- * @first_vec:	first interrupt vectors to use for queues (usually 0)
- *
- * This function assumes the rdma device @dev has at least as many available
- * interrupt vetors as @set has queues.  It will then query it's affinity mask
- * and built queue mapping that maps a queue to the CPUs that have irq affinity
- * for the corresponding vector.
- *
- * In case either the driver passed a @dev with less vectors than
- * @set->nr_hw_queues, or @dev does not provide an affinity mask for a
- * vector, we fallback to the naive mapping.
- */
-int blk_mq_rdma_map_queues(struct blk_mq_queue_map *map,
-		struct ib_device *dev, int first_vec)
-{
-	const struct cpumask *mask;
-	unsigned int queue, cpu;
-
-	for (queue = 0; queue < map->nr_queues; queue++) {
-		mask = ib_get_vector_affinity(dev, first_vec + queue);
-		if (!mask)
-			goto fallback;
-
-		for_each_cpu(cpu, mask)
-			map->mq_map[cpu] = map->queue_offset + queue;
-	}
-
-	return 0;
-
-fallback:
-	return blk_mq_map_queues(map);
-}
-EXPORT_SYMBOL_GPL(blk_mq_rdma_map_queues);
diff --git a/drivers/nvme/host/rdma.c b/drivers/nvme/host/rdma.c
index 9e378d0a0c01..5989d4e35ef3 100644
--- a/drivers/nvme/host/rdma.c
+++ b/drivers/nvme/host/rdma.c
@@ -12,7 +12,6 @@
 #include <linux/string.h>
 #include <linux/atomic.h>
 #include <linux/blk-mq.h>
-#include <linux/blk-mq-rdma.h>
 #include <linux/types.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
@@ -2171,10 +2170,8 @@ static int nvme_rdma_map_queues(struct blk_mq_tag_set *set)
 			ctrl->io_queues[HCTX_TYPE_DEFAULT];
 		set->map[HCTX_TYPE_READ].queue_offset = 0;
 	}
-	blk_mq_rdma_map_queues(&set->map[HCTX_TYPE_DEFAULT],
-			ctrl->device->dev, 0);
-	blk_mq_rdma_map_queues(&set->map[HCTX_TYPE_READ],
-			ctrl->device->dev, 0);
+	blk_mq_map_queues(&set->map[HCTX_TYPE_DEFAULT]);
+	blk_mq_map_queues(&set->map[HCTX_TYPE_READ]);

 	if (opts->nr_poll_queues && ctrl->io_queues[HCTX_TYPE_POLL]) {
 		/* map dedicated poll queues only if we have queues left */
diff --git a/include/linux/blk-mq-rdma.h b/include/linux/blk-mq-rdma.h
deleted file mode 100644
index 5cc5f0f36218..000000000000
--- a/include/linux/blk-mq-rdma.h
+++ /dev/null
@@ -1,11 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _LINUX_BLK_MQ_RDMA_H
-#define _LINUX_BLK_MQ_RDMA_H
-
-struct blk_mq_tag_set;
-struct ib_device;
-
-int blk_mq_rdma_map_queues(struct blk_mq_queue_map *map,
-		struct ib_device *dev, int first_vec);
-
-#endif /* _LINUX_BLK_MQ_RDMA_H */
--
2.26.2