io_uring: move uring_cmd handling to its own file

Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 115 insertions, 0 deletions

diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
new file mode 100644
index 000000000000..abf78918a099
--- /dev/null
+++ b/io_uring/uring_cmd.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/io_uring.h>
+
+#include <uapi/linux/io_uring.h>
+
+#include "io_uring_types.h"
+#include "io_uring.h"
+#include "uring_cmd.h"
+
+static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+
+	ioucmd->task_work_cb(ioucmd);
+}
+
+void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
+			void (*task_work_cb)(struct io_uring_cmd *))
+{
+	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
+
+	ioucmd->task_work_cb = task_work_cb;
+	req->io_task_work.func = io_uring_cmd_work;
+	io_req_task_work_add(req);
+}
+EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
+
+static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
+					  u64 extra1, u64 extra2)
+{
+	req->extra1 = extra1;
+	req->extra2 = extra2;
+	req->flags |= REQ_F_CQE32_INIT;
+}
+
+/*
+ * Called by consumers of io_uring_cmd, if they originally returned
+ * -EIOCBQUEUED upon receiving the command.
+ */
+void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
+{
+	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
+
+	if (ret < 0)
+		req_set_fail(req);
+
+	io_req_set_res(req, 0, ret);
+	if (req->ctx->flags & IORING_SETUP_CQE32)
+		io_req_set_cqe32_extra(req, res2, 0);
+	__io_req_complete(req, 0);
+}
+EXPORT_SYMBOL_GPL(io_uring_cmd_done);
+
+int io_uring_cmd_prep_async(struct io_kiocb *req)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+	size_t cmd_size;
+
+	cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
+
+	memcpy(req->async_data, ioucmd->cmd, cmd_size);
+	return 0;
+}
+
+int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+
+	if (sqe->rw_flags || sqe->__pad1)
+		return -EINVAL;
+	ioucmd->cmd = sqe->cmd;
+	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
+	return 0;
+}
+
+int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+	struct io_ring_ctx *ctx = req->ctx;
+	struct file *file = req->file;
+	int ret;
+
+	if (!req->file->f_op->uring_cmd)
+		return -EOPNOTSUPP;
+
+	if (ctx->flags & IORING_SETUP_SQE128)
+		issue_flags |= IO_URING_F_SQE128;
+	if (ctx->flags & IORING_SETUP_CQE32)
+		issue_flags |= IO_URING_F_CQE32;
+	if (ctx->flags & IORING_SETUP_IOPOLL)
+		issue_flags |= IO_URING_F_IOPOLL;
+
+	if (req_has_async_data(req))
+		ioucmd->cmd = req->async_data;
+
+	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
+	if (ret == -EAGAIN) {
+		if (!req_has_async_data(req)) {
+			if (io_alloc_async_data(req))
+				return -ENOMEM;
+			io_uring_cmd_prep_async(req);
+		}
+		return -EAGAIN;
+	}
+
+	if (ret != -EIOCBQUEUED) {
+		io_uring_cmd_done(ioucmd, ret, 0);
+		return IOU_OK;
+	}
+
+	return IOU_ISSUE_SKIP_COMPLETE;
+}