Commit 252917c3 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: follow **iovec idiom in io_import_iovec 



As for import_iovec(), return !=NULL iovec from io_import_iovec() only
when it should be freed. That includes returning NULL when iovec is
already in req->io, because it should be deallocated by other means,
e.g. inside op handler. After io_setup_async_rw() local iovec to ->io,
just mark it NULL, to follow the idea in io_{read,write} as well.

That's easier to follow, and especially useful if we want to reuse
per-op space for completion data.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
[axboe: only call kfree() on non-NULL pointer]
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent c3e330a4

fs/io_uring.c

+8 −6
Original line number Diff line number Diff line
@@ -2740,9 +2740,7 @@ static ssize_t io_import_iovec(int rw, struct io_kiocb *req, 
	if (req->io) {

		struct io_async_rw *iorw = &req->io->rw;



		*iovec = iorw->iov;

		iov_iter_init(iter, rw, *iovec, iorw->nr_segs, iorw->size);

		if (iorw->iov == iorw->fast_iov)

		iov_iter_init(iter, rw, iorw->iov, iorw->nr_segs, iorw->size);

		*iovec = NULL;

		return iorw->size;

	}
@@ -3026,6 +3024,8 @@ static int io_read(struct io_kiocb *req, bool force_nonblock, 
						inline_vecs, &iter);

			if (ret)

				goto out_free;

			/* it's copied and will be cleaned with ->io */

			iovec = NULL;

			/* if we can retry, do so with the callbacks armed */

			if (io_rw_should_retry(req)) {

				ret2 = io_iter_do_read(req, &iter);
@@ -3041,7 +3041,7 @@ static int io_read(struct io_kiocb *req, bool force_nonblock, 
		}

	}

out_free:

	if (!(req->flags & REQ_F_NEED_CLEANUP))

	if (iovec)

		kfree(iovec);

	return ret;

}
@@ -3143,11 +3143,13 @@ static int io_write(struct io_kiocb *req, bool force_nonblock, 
						inline_vecs, &iter);

			if (ret)

				goto out_free;

			/* it's copied and will be cleaned with ->io */

			iovec = NULL;

			return -EAGAIN;

		}

	}

out_free:

	if (!(req->flags & REQ_F_NEED_CLEANUP))

	if (iovec)

		kfree(iovec);

	return ret;

}