[PATCH 03/27] block: wire up block device iopoll method

[Jens Axboe]

From: Christoph Hellwig <h...@lst.de>

Just call blk_poll on the iocb cookie, we can derive the block device
from the inode trivially.

Reviewed-by: Johannes Thumshirn <jthumsh...@suse.de>
Signed-off-by: Christoph Hellwig <h...@lst.de>
Signed-off-by: Jens Axboe <ax...@kernel.dk>
---
 fs/block_dev.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/fs/block_dev.c b/fs/block_dev.c
index e1886cc7048f..6de8d35f6e41 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -281,6 +281,14 @@ struct blkdev_dio {
 
 static struct bio_set blkdev_dio_pool;
 
+static int blkdev_iopoll(struct kiocb *kiocb, bool wait)
+{
+       struct block_device *bdev = I_BDEV(kiocb->ki_filp->f_mapping->host);
+       struct request_queue *q = bdev_get_queue(bdev);
+
+       return blk_poll(q, READ_ONCE(kiocb->ki_cookie), wait);
+}
+
 static void blkdev_bio_end_io(struct bio *bio)
 {
        struct blkdev_dio *dio = bio->bi_private;
@@ -398,6 +406,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter 
*iter, int nr_pages)
                                bio->bi_opf |= REQ_HIPRI;
 
                        qc = submit_bio(bio);
+                       WRITE_ONCE(iocb->ki_cookie, qc);
                        break;
                }
 
@@ -2070,6 +2079,7 @@ const struct file_operations def_blk_fops = {
        .llseek         = block_llseek,
        .read_iter      = blkdev_read_iter,
        .write_iter     = blkdev_write_iter,
+       .iopoll         = blkdev_iopoll,
        .mmap           = generic_file_mmap,
        .fsync          = blkdev_fsync,
        .unlocked_ioctl = block_ioctl,
-- 
2.17.1