Re: [PATCH 04/18] iomap: wire up the iopoll method
flat view
From: Jens Axboe <axboe@kernel.dk>
Date: 2019-02-06 20:05:06
Also in:
linux-block
On 2/1/19 9:59 AM, Bart Van Assche wrote:
On Fri, 2019-02-01 at 08:24 -0700, Jens Axboe wrote:quoted
+int iomap_dio_iopoll(struct kiocb *kiocb, bool spin) +{ + struct request_queue *q = READ_ONCE(kiocb->private); + + if (!q) + return 0; + return blk_poll(q, READ_ONCE(kiocb->ki_cookie), spin); +} +EXPORT_SYMBOL_GPL(iomap_dio_iopoll);How does this interact with block device removal? My understanding is that this function can get called after a request has completed. Which mechanism, if any, prevents that request queue 'q' is removed after kiocb->private has been read and before blk_poll() is called?
The completion event is split from the reap, the latter being the one that would put the file. So we're never going to call into ->iopoll() for a kiocb where we've done the file put. -- Jens Axboe -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: <a href=mailto:"aart@kvack.org">aart@kvack.org</a>