block: interface update for ioc/icq creation functions

Make the following interface updates to prepare for future ioc related
changes.

* create_io_context() returning ioc only works for %current because it
  doesn't increment ref on the ioc.  Drop @task parameter from it and
  always assume %current.

* Make create_io_context_slowpath() return 0 or -errno and rename it
  to create_task_io_context().

* Make ioc_create_icq() take @ioc as parameter instead of assuming
  that of %current.  The caller, get_request(), is updated to create
  ioc explicitly and then pass it into ioc_create_icq().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 5 insertions, 3 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index 792a384a8e35..b2d0fcd8f87f 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -855,7 +855,7 @@ retry:
                          */
                         if (!ioc && !retried) {
                                 spin_unlock_irq(q->queue_lock);
-                                create_io_context(current, gfp_mask, q->node);
+                                create_io_context(gfp_mask, q->node);
                                 spin_lock_irq(q->queue_lock);
                                 retried = true;
                                 goto retry;
@@ -919,7 +919,9 @@ retry:
 
         /* create icq if missing */
         if ((rw_flags & REQ_ELVPRIV) && unlikely(et->icq_cache && !icq)) {
-                icq = ioc_create_icq(q, gfp_mask);
+                ioc = create_io_context(gfp_mask, q->node);
+                if (ioc)
+                        icq = ioc_create_icq(ioc, q, gfp_mask);
                 if (!icq)
                         goto fail_alloc;
         }
@@ -1005,7 +1007,7 @@ static struct request *get_request_wait(struct request_queue *q, int rw_flags,
                  * up to a big batch of them for a small period time.
                  * See ioc_batching, ioc_set_batching
                  */
-                create_io_context(current, GFP_NOIO, q->node);
+                create_io_context(GFP_NOIO, q->node);
                 ioc_set_batching(q, current->io_context);
 
                 spin_lock_irq(q->queue_lock);