[linux-block.git] / io_uring / uring_cmd.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/io_uring.h>
#include <linux/security.h>
#include <linux/nospec.h>

#include <uapi/linux/io_uring.h>

#include "io_uring.h"
#include "rsrc.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, struct io_uring_cmd);

	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, ret, 0);
	if (req->ctx->flags & IORING_SETUP_CQE32)
		io_req_set_cqe32_extra(req, res2, 0);
	if (req->ctx->flags & IORING_SETUP_IOPOLL)
		/* order with io_iopoll_req_issued() checking ->iopoll_complete */
		smp_store_release(&req->iopoll_completed, 1);
	else
		io_req_complete_post(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, struct io_uring_cmd);
	size_t cmd_size;

	BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16);
	BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80);

	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, struct io_uring_cmd);

	if (sqe->__pad1)
		return -EINVAL;

	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
	if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
		return -EINVAL;

	if (ioucmd->flags & IORING_URING_CMD_FIXED) {
		struct io_ring_ctx *ctx = req->ctx;
		u16 index;

		req->buf_index = READ_ONCE(sqe->buf_index);
		if (unlikely(req->buf_index >= ctx->nr_user_bufs))
			return -EFAULT;
		index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
		req->imu = ctx->user_bufs[index];
		io_req_set_rsrc_node(req, ctx, 0);
	}
	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_uring_cmd);
	struct io_ring_ctx *ctx = req->ctx;
	struct file *file = req->file;
	int ret;

	if (!req->file->f_op->uring_cmd)
		return -EOPNOTSUPP;

	ret = security_uring_cmd(ioucmd);
	if (ret)
		return ret;

	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;
		req->iopoll_completed = 0;
		WRITE_ONCE(ioucmd->cookie, NULL);
	}

	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) {
		if (ret < 0)
			req_set_fail(req);
		io_req_set_res(req, ret, 0);
		return ret;
	}

	return IOU_ISSUE_SKIP_COMPLETE;
}

int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
			      struct iov_iter *iter, void *ioucmd)
{
	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);

	return io_import_fixed(rw, iter, req->imu, ubuf, len);
}
EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);
Commit	Line	Data
99f15d8d JA	1	// SPDX-License-Identifier: GPL-2.0
	2	#include <linux/kernel.h>
	3	#include <linux/errno.h>
	4	#include <linux/file.h>
	5	#include <linux/io_uring.h>
2a584012	6	#include <linux/security.h>
9cda70f6	7	#include <linux/nospec.h>
99f15d8d JA	8
	9	#include <uapi/linux/io_uring.h>
	10
99f15d8d	11	#include "io_uring.h"
a9216fac	12	#include "rsrc.h"
99f15d8d JA	13	#include "uring_cmd.h"
	14
	15	static void io_uring_cmd_work(struct io_kiocb req, bool locked)
	16	{
f2ccb5ae	17	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d JA	18
	19	ioucmd->task_work_cb(ioucmd);
	20	}
	21
	22	void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
	23	void (task_work_cb)(struct io_uring_cmd ))
	24	{
	25	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	26
	27	ioucmd->task_work_cb = task_work_cb;
	28	req->io_task_work.func = io_uring_cmd_work;
	29	io_req_task_work_add(req);
	30	}
	31	EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
	32
	33	static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
	34	u64 extra1, u64 extra2)
	35	{
	36	req->extra1 = extra1;
	37	req->extra2 = extra2;
	38	req->flags \|= REQ_F_CQE32_INIT;
	39	}
	40
	41	/*
	42	* Called by consumers of io_uring_cmd, if they originally returned
	43	* -EIOCBQUEUED upon receiving the command.
	44	*/
	45	void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
	46	{
	47	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	48
	49	if (ret < 0)
	50	req_set_fail(req);
	51
ff2557b7	52	io_req_set_res(req, ret, 0);
99f15d8d JA	53	if (req->ctx->flags & IORING_SETUP_CQE32)
99f15d8d JA	54	io_req_set_cqe32_extra(req, res2, 0);
5756a3a7 KJ	55	if (req->ctx->flags & IORING_SETUP_IOPOLL)
	56	/* order with io_iopoll_req_issued() checking ->iopoll_complete */
	57	smp_store_release(&req->iopoll_completed, 1);
	58	else
1bec951c	59	io_req_complete_post(req, 0);
99f15d8d JA	60	}
	61	EXPORT_SYMBOL_GPL(io_uring_cmd_done);
	62
	63	int io_uring_cmd_prep_async(struct io_kiocb *req)
	64	{
f2ccb5ae	65	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d JA	66	size_t cmd_size;
99f15d8d JA	67
9c71d39a SM	68	BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16);
	69	BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80);
	70
99f15d8d JA	71	cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
	72
	73	memcpy(req->async_data, ioucmd->cmd, cmd_size);
	74	return 0;
	75	}
	76
	77	int io_uring_cmd_prep(struct io_kiocb req, const struct io_uring_sqe sqe)
	78	{
f2ccb5ae	79	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d	80
9cda70f6	81	if (sqe->__pad1)
99f15d8d	82	return -EINVAL;
9cda70f6 AG	83
	84	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
	85	if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
	86	return -EINVAL;
	87
	88	if (ioucmd->flags & IORING_URING_CMD_FIXED) {
	89	struct io_ring_ctx *ctx = req->ctx;
	90	u16 index;
	91
	92	req->buf_index = READ_ONCE(sqe->buf_index);
	93	if (unlikely(req->buf_index >= ctx->nr_user_bufs))
	94	return -EFAULT;
	95	index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
	96	req->imu = ctx->user_bufs[index];
	97	io_req_set_rsrc_node(req, ctx, 0);
	98	}
99f15d8d JA	99	ioucmd->cmd = sqe->cmd;
	100	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
	101	return 0;
	102	}
	103
	104	int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
	105	{
f2ccb5ae	106	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d JA	107	struct io_ring_ctx *ctx = req->ctx;
	108	struct file *file = req->file;
	109	int ret;
	110
	111	if (!req->file->f_op->uring_cmd)
	112	return -EOPNOTSUPP;
	113
2a584012 LC	114	ret = security_uring_cmd(ioucmd);
	115	if (ret)
	116	return ret;
	117
99f15d8d JA	118	if (ctx->flags & IORING_SETUP_SQE128)
	119	issue_flags \|= IO_URING_F_SQE128;
	120	if (ctx->flags & IORING_SETUP_CQE32)
	121	issue_flags \|= IO_URING_F_CQE32;
5756a3a7	122	if (ctx->flags & IORING_SETUP_IOPOLL) {
99f15d8d	123	issue_flags \|= IO_URING_F_IOPOLL;
5756a3a7 KJ	124	req->iopoll_completed = 0;
	125	WRITE_ONCE(ioucmd->cookie, NULL);
	126	}
99f15d8d JA	127
	128	if (req_has_async_data(req))
	129	ioucmd->cmd = req->async_data;
	130
	131	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
	132	if (ret == -EAGAIN) {
	133	if (!req_has_async_data(req)) {
	134	if (io_alloc_async_data(req))
	135	return -ENOMEM;
	136	io_uring_cmd_prep_async(req);
	137	}
	138	return -EAGAIN;
	139	}
	140
	141	if (ret != -EIOCBQUEUED) {
3ed159c9 AG	142	if (ret < 0)
	143	req_set_fail(req);
	144	io_req_set_res(req, ret, 0);
a9c3eda7	145	return ret;
99f15d8d JA	146	}
	147
	148	return IOU_ISSUE_SKIP_COMPLETE;
	149	}
a9216fac AG	150
	151	int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
	152	struct iov_iter iter, void ioucmd)
	153	{
	154	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	155
	156	return io_import_fixed(rw, iter, req->imu, ubuf, len);
	157	}
	158	EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);