Re: [patch] aio: invalidate async directio writes

[Christoph Hellwig <hch@infradead.org>]

On Wed, Jun 18, 2008 at 02:09:51PM -0400, Jeff Moyer wrote:
> +		/* For async O_DIRECT writes, we need to invalidate the 
> +		 * page cache after the write completes.  Kick off a
> +		 * workqueue to do this and issue the completion in process
> +		 * context.
> +		 */
> +		if (dio->rw == READ) {
> +			int ret = dio_complete(dio, dio->iocb->ki_pos, 0);
> +			aio_complete(dio->iocb, ret, 0);
> +			kfree(dio);
> +		} else {
> +			unsigned long flags;
> +			spin_lock_irqsave(&iocb_completion_list_lock, flags);
> +			list_add(&dio->done_list, &iocb_completion_list);
> +			spin_unlock_irqrestore(&iocb_completion_list_lock, flags);
> +			schedule_work(&aio_complete_work);
> +		}

Can we please move all these aio_complete calls to user context?  Having
AIO contexts completing from irq context is a major pain for complex
filesystems like XFS.