block: factor out a alloc_io_context helper

Factor out a helper that just allocate an I/O context.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211126115817.2087431-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/blk-ioc.c b/block/blk-ioc.c
index cc4eb2b..b42fbb8 100644 (file)
--- a/block/blk-ioc.c
+++ b/block/blk-ioc.c
@@ -249,18 +249,15 @@ void ioc_clear_queue(struct request_queue *q)
        __ioc_clear_queue(&icq_list);
 }
 
-static int create_task_io_context(struct task_struct *task, gfp_t gfp_flags,
-               int node)
+static struct io_context *alloc_io_context(gfp_t gfp_flags, int node)
 {
        struct io_context *ioc;
-       int ret;
 
        ioc = kmem_cache_alloc_node(iocontext_cachep, gfp_flags | __GFP_ZERO,
                                    node);
        if (unlikely(!ioc))
-               return -ENOMEM;
+               return NULL;
 
-       /* initialize */
        atomic_long_set(&ioc->refcount, 1);
        atomic_set(&ioc->nr_tasks, 1);
        atomic_set(&ioc->active_ref, 1);
@@ -268,6 +265,18 @@ static int create_task_io_context(struct task_struct *task, gfp_t gfp_flags,
        INIT_RADIX_TREE(&ioc->icq_tree, GFP_ATOMIC);
        INIT_HLIST_HEAD(&ioc->icq_list);
        INIT_WORK(&ioc->release_work, ioc_release_fn);
+       return ioc;
+}
+
+static int create_task_io_context(struct task_struct *task, gfp_t gfp_flags,
+               int node)
+{
+       struct io_context *ioc;
+       int ret;
+
+       ioc = alloc_io_context(gfp_flags, node);
+       if (!ioc)
+               return -ENOMEM;
 
        /*
         * Try to install.  ioc shouldn't be installed if someone else