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>
diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index 92bf555..1092874 100644
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -212,15 +212,14 @@
}
}
-void create_io_context_slowpath(struct task_struct *task, gfp_t gfp_flags,
- int node)
+int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, int node)
{
struct io_context *ioc;
ioc = kmem_cache_alloc_node(iocontext_cachep, gfp_flags | __GFP_ZERO,
node);
if (unlikely(!ioc))
- return;
+ return -ENOMEM;
/* initialize */
atomic_long_set(&ioc->refcount, 1);
@@ -244,6 +243,8 @@
else
kmem_cache_free(iocontext_cachep, ioc);
task_unlock(task);
+
+ return 0;
}
/**
@@ -275,7 +276,7 @@
return ioc;
}
task_unlock(task);
- } while (create_io_context(task, gfp_flags, node));
+ } while (!create_task_io_context(task, gfp_flags, node));
return NULL;
}
@@ -319,26 +320,23 @@
/**
* ioc_create_icq - create and link io_cq
+ * @ioc: io_context of interest
* @q: request_queue of interest
* @gfp_mask: allocation mask
*
- * Make sure io_cq linking %current->io_context and @q exists. If either
- * io_context and/or icq don't exist, they will be created using @gfp_mask.
+ * Make sure io_cq linking @ioc and @q exists. If icq doesn't exist, they
+ * will be created using @gfp_mask.
*
* The caller is responsible for ensuring @ioc won't go away and @q is
* alive and will stay alive until this function returns.
*/
-struct io_cq *ioc_create_icq(struct request_queue *q, gfp_t gfp_mask)
+struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
+ gfp_t gfp_mask)
{
struct elevator_type *et = q->elevator->type;
- struct io_context *ioc;
struct io_cq *icq;
/* allocate stuff */
- ioc = create_io_context(current, gfp_mask, q->node);
- if (!ioc)
- return NULL;
-
icq = kmem_cache_alloc_node(et->icq_cache, gfp_mask | __GFP_ZERO,
q->node);
if (!icq)