diff options
Diffstat (limited to 'block/blk-ioc.c')
| -rw-r--r-- | block/blk-ioc.c | 39 |
1 files changed, 35 insertions, 4 deletions
diff --git a/block/blk-ioc.c b/block/blk-ioc.c index f3ff495756cb..f4f84a2072be 100644 --- a/block/blk-ioc.c +++ b/block/blk-ioc.c @@ -24,7 +24,7 @@ static struct kmem_cache *iocontext_cachep; * * Increment reference count to @ioc. */ -void get_io_context(struct io_context *ioc) +static void get_io_context(struct io_context *ioc) { BUG_ON(atomic_long_read(&ioc->refcount) <= 0); atomic_long_inc(&ioc->refcount); @@ -248,7 +248,8 @@ void ioc_clear_queue(struct request_queue *q) __ioc_clear_queue(&icq_list); } -int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, int node) +static int create_task_io_context(struct task_struct *task, gfp_t gfp_flags, + int node) { struct io_context *ioc; int ret; @@ -397,8 +398,8 @@ EXPORT_SYMBOL(ioc_lookup_icq); * 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 io_context *ioc, struct request_queue *q, - gfp_t gfp_mask) +static 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_cq *icq; @@ -441,6 +442,36 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, return icq; } +struct io_cq *ioc_find_get_icq(struct request_queue *q) +{ + struct io_context *ioc; + struct io_cq *icq; + + /* create task io_context, if we don't have one already */ + if (unlikely(!current->io_context)) + create_task_io_context(current, GFP_ATOMIC, q->node); + + /* + * May not have an IO context if it's a passthrough request + */ + ioc = current->io_context; + if (!ioc) + return NULL; + + spin_lock_irq(&q->queue_lock); + icq = ioc_lookup_icq(ioc, q); + spin_unlock_irq(&q->queue_lock); + + if (!icq) { + icq = ioc_create_icq(ioc, q, GFP_ATOMIC); + if (!icq) + return NULL; + } + get_io_context(icq->ioc); + return icq; +} +EXPORT_SYMBOL_GPL(ioc_find_get_icq); + static int __init blk_ioc_init(void) { iocontext_cachep = kmem_cache_create("blkdev_ioc", |