[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);
	unsigned issue_flags = *locked ? 0 : IO_URING_F_UNLOCKED;

	ioucmd->task_work_cb(ioucmd, issue_flags);
}

void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned))
{
	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,
		       unsigned issue_flags)
{
	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, issue_flags);
}
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 (!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) {
		if (!file->f_op->uring_cmd_iopoll)
			return -EOPNOTSUPP;
		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);
9d2789ac	18	unsigned issue_flags = *locked ? 0 : IO_URING_F_UNLOCKED;
99f15d8d	19
9d2789ac	20	ioucmd->task_work_cb(ioucmd, issue_flags);
99f15d8d JA	21	}
	22
	23	void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
9d2789ac	24	void (task_work_cb)(struct io_uring_cmd , unsigned))
99f15d8d JA	25	{
	26	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	27
	28	ioucmd->task_work_cb = task_work_cb;
	29	req->io_task_work.func = io_uring_cmd_work;
	30	io_req_task_work_add(req);
	31	}
	32	EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
	33
	34	static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
	35	u64 extra1, u64 extra2)
	36	{
	37	req->extra1 = extra1;
	38	req->extra2 = extra2;
	39	req->flags \|= REQ_F_CQE32_INIT;
	40	}
	41
	42	/*
	43	* Called by consumers of io_uring_cmd, if they originally returned
	44	* -EIOCBQUEUED upon receiving the command.
	45	*/
9d2789ac JA	46	void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,
9d2789ac JA	47	unsigned issue_flags)
99f15d8d JA	48	{
	49	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	50
	51	if (ret < 0)
	52	req_set_fail(req);
	53
ff2557b7	54	io_req_set_res(req, ret, 0);
99f15d8d JA	55	if (req->ctx->flags & IORING_SETUP_CQE32)
99f15d8d JA	56	io_req_set_cqe32_extra(req, res2, 0);
5756a3a7 KJ	57	if (req->ctx->flags & IORING_SETUP_IOPOLL)
	58	/* order with io_iopoll_req_issued() checking ->iopoll_complete */
	59	smp_store_release(&req->iopoll_completed, 1);
	60	else
9d2789ac	61	io_req_complete_post(req, issue_flags);
99f15d8d JA	62	}
	63	EXPORT_SYMBOL_GPL(io_uring_cmd_done);
	64
	65	int io_uring_cmd_prep_async(struct io_kiocb *req)
	66	{
f2ccb5ae	67	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d JA	68	size_t cmd_size;
99f15d8d JA	69
9c71d39a SM	70	BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16);
	71	BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80);
	72
99f15d8d JA	73	cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
	74
	75	memcpy(req->async_data, ioucmd->cmd, cmd_size);
	76	return 0;
	77	}
	78
	79	int io_uring_cmd_prep(struct io_kiocb req, const struct io_uring_sqe sqe)
	80	{
f2ccb5ae	81	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d	82
9cda70f6	83	if (sqe->__pad1)
99f15d8d	84	return -EINVAL;
9cda70f6 AG	85
	86	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
	87	if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
	88	return -EINVAL;
	89
	90	if (ioucmd->flags & IORING_URING_CMD_FIXED) {
	91	struct io_ring_ctx *ctx = req->ctx;
	92	u16 index;
	93
	94	req->buf_index = READ_ONCE(sqe->buf_index);
	95	if (unlikely(req->buf_index >= ctx->nr_user_bufs))
	96	return -EFAULT;
	97	index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
	98	req->imu = ctx->user_bufs[index];
	99	io_req_set_rsrc_node(req, ctx, 0);
	100	}
99f15d8d JA	101	ioucmd->cmd = sqe->cmd;
	102	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
	103	return 0;
	104	}
	105
	106	int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
	107	{
f2ccb5ae	108	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d JA	109	struct io_ring_ctx *ctx = req->ctx;
	110	struct file *file = req->file;
	111	int ret;
	112
03b3d6be	113	if (!file->f_op->uring_cmd)
99f15d8d JA	114	return -EOPNOTSUPP;
99f15d8d JA	115
2a584012 LC	116	ret = security_uring_cmd(ioucmd);
	117	if (ret)
	118	return ret;
	119
99f15d8d JA	120	if (ctx->flags & IORING_SETUP_SQE128)
	121	issue_flags \|= IO_URING_F_SQE128;
	122	if (ctx->flags & IORING_SETUP_CQE32)
	123	issue_flags \|= IO_URING_F_CQE32;
5756a3a7	124	if (ctx->flags & IORING_SETUP_IOPOLL) {
03b3d6be JA	125	if (!file->f_op->uring_cmd_iopoll)
03b3d6be JA	126	return -EOPNOTSUPP;
99f15d8d	127	issue_flags \|= IO_URING_F_IOPOLL;
5756a3a7 KJ	128	req->iopoll_completed = 0;
	129	WRITE_ONCE(ioucmd->cookie, NULL);
	130	}
99f15d8d JA	131
	132	if (req_has_async_data(req))
	133	ioucmd->cmd = req->async_data;
	134
	135	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
	136	if (ret == -EAGAIN) {
	137	if (!req_has_async_data(req)) {
	138	if (io_alloc_async_data(req))
	139	return -ENOMEM;
	140	io_uring_cmd_prep_async(req);
	141	}
	142	return -EAGAIN;
	143	}
	144
	145	if (ret != -EIOCBQUEUED) {
3ed159c9 AG	146	if (ret < 0)
	147	req_set_fail(req);
	148	io_req_set_res(req, ret, 0);
a9c3eda7	149	return ret;
99f15d8d JA	150	}
	151
	152	return IOU_ISSUE_SKIP_COMPLETE;
	153	}
a9216fac AG	154
	155	int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
	156	struct iov_iter iter, void ioucmd)
	157	{
	158	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	159
	160	return io_import_fixed(rw, iter, req->imu, ubuf, len);
	161	}
	162	EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);