blk-mq: allow the driver to pass in a queue mapping

This allows drivers specify their own queue mapping by overriding the
setup-time function that builds the mq_map.  This can be used for
example to build the map based on the MSI-X vector mapping provided
by the core interrupt layer for PCI devices.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

1 files changed, 5 insertions, 20 deletions

diff --git a/block/blk-mq-cpumap.c b/block/blk-mq-cpumap.c
index d0634bcf322f..19b1d9c5f07e 100644
--- a/block/blk-mq-cpumap.c
+++ b/block/blk-mq-cpumap.c
@@ -31,14 +31,16 @@ static int get_first_sibling(unsigned int cpu)
         return cpu;
 }
 
-int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues,
-                            const struct cpumask *online_mask)
+int blk_mq_map_queues(struct blk_mq_tag_set *set)
 {
+        unsigned int *map = set->mq_map;
+        unsigned int nr_queues = set->nr_hw_queues;
+        const struct cpumask *online_mask = cpu_online_mask;
         unsigned int i, nr_cpus, nr_uniq_cpus, queue, first_sibling;
         cpumask_var_t cpus;
 
         if (!alloc_cpumask_var(&cpus, GFP_ATOMIC))
-                return 1;
+                return -ENOMEM;
 
         cpumask_clear(cpus);
         nr_cpus = nr_uniq_cpus = 0;
@@ -86,23 +88,6 @@ int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues,
         return 0;
 }
 
-unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set)
-{
-        unsigned int *map;
-
-        /* If cpus are offline, map them to first hctx */
-        map = kzalloc_node(sizeof(*map) * nr_cpu_ids, GFP_KERNEL,
-                                set->numa_node);
-        if (!map)
-                return NULL;
-
-        if (!blk_mq_update_queue_map(map, set->nr_hw_queues, cpu_online_mask))
-                return map;
-
-        kfree(map);
-        return NULL;
-}
-
 /*
  * We have no quick way of doing reverse lookups. This is only used at
  * queue init time, so runtime isn't important.