[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, struct io_tw_state *ts)
{
	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
	unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;

	ioucmd->task_work_cb(ioucmd, issue_flags);
}

void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned),
			unsigned flags)
{
	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, flags);
}
EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);

void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
			void (*task_work_cb)(struct io_uring_cmd *, unsigned))
{
	__io_uring_cmd_do_in_task(ioucmd, task_work_cb, IOU_F_TWQ_LAZY_WAKE);
}
EXPORT_SYMBOL_GPL(io_uring_cmd_do_in_task_lazy);

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 {
		struct io_tw_state ts = {
			.locked = !(issue_flags & IO_URING_F_UNLOCKED),
		};
		io_req_task_complete(req, &ts);
	}
}
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);

	memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx));
	ioucmd->sqe = req->async_data;
	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->sqe = sqe;
	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);
	}

	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"
99f15d8d JA	14
a282967c	15	static void io_uring_cmd_work(struct io_kiocb req, struct io_tw_state ts)
99f15d8d	16	{
f2ccb5ae	17	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
a282967c	18	unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;
99f15d8d	19
9d2789ac	20	ioucmd->task_work_cb(ioucmd, issue_flags);
99f15d8d JA	21	}
99f15d8d JA	22
5f3139fc PB	23	void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,
	24	void (task_work_cb)(struct io_uring_cmd , unsigned),
	25	unsigned flags)
99f15d8d JA	26	{
	27	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	28
	29	ioucmd->task_work_cb = task_work_cb;
	30	req->io_task_work.func = io_uring_cmd_work;
5f3139fc PB	31	__io_req_task_work_add(req, flags);
	32	}
	33	EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);
	34
	35	void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
	36	void (task_work_cb)(struct io_uring_cmd , unsigned))
	37	{
	38	__io_uring_cmd_do_in_task(ioucmd, task_work_cb, IOU_F_TWQ_LAZY_WAKE);
99f15d8d	39	}
5f3139fc	40	EXPORT_SYMBOL_GPL(io_uring_cmd_do_in_task_lazy);
99f15d8d JA	41
	42	static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
	43	u64 extra1, u64 extra2)
	44	{
	45	req->extra1 = extra1;
	46	req->extra2 = extra2;
	47	req->flags \|= REQ_F_CQE32_INIT;
	48	}
	49
	50	/*
	51	* Called by consumers of io_uring_cmd, if they originally returned
	52	* -EIOCBQUEUED upon receiving the command.
	53	*/
9d2789ac JA	54	void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,
9d2789ac JA	55	unsigned issue_flags)
99f15d8d JA	56	{
	57	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	58
	59	if (ret < 0)
	60	req_set_fail(req);
	61
ff2557b7	62	io_req_set_res(req, ret, 0);
99f15d8d JA	63	if (req->ctx->flags & IORING_SETUP_CQE32)
99f15d8d JA	64	io_req_set_cqe32_extra(req, res2, 0);
27a67079	65	if (req->ctx->flags & IORING_SETUP_IOPOLL) {
5756a3a7 KJ	66	/* order with io_iopoll_req_issued() checking ->iopoll_complete */
5756a3a7 KJ	67	smp_store_release(&req->iopoll_completed, 1);
27a67079 JA	68	} else {
	69	struct io_tw_state ts = {
	70	.locked = !(issue_flags & IO_URING_F_UNLOCKED),
	71	};
	72	io_req_task_complete(req, &ts);
	73	}
99f15d8d JA	74	}
	75	EXPORT_SYMBOL_GPL(io_uring_cmd_done);
	76
	77	int io_uring_cmd_prep_async(struct io_kiocb *req)
	78	{
f2ccb5ae	79	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d	80
fd9b8547 BL	81	memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx));
fd9b8547 BL	82	ioucmd->sqe = req->async_data;
99f15d8d JA	83	return 0;
	84	}
	85
	86	int io_uring_cmd_prep(struct io_kiocb req, const struct io_uring_sqe sqe)
	87	{
f2ccb5ae	88	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d	89
9cda70f6	90	if (sqe->__pad1)
99f15d8d	91	return -EINVAL;
9cda70f6 AG	92
	93	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);
	94	if (ioucmd->flags & ~IORING_URING_CMD_FIXED)
	95	return -EINVAL;
	96
	97	if (ioucmd->flags & IORING_URING_CMD_FIXED) {
	98	struct io_ring_ctx *ctx = req->ctx;
	99	u16 index;
	100
	101	req->buf_index = READ_ONCE(sqe->buf_index);
	102	if (unlikely(req->buf_index >= ctx->nr_user_bufs))
	103	return -EFAULT;
	104	index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
	105	req->imu = ctx->user_bufs[index];
	106	io_req_set_rsrc_node(req, ctx, 0);
	107	}
fd9b8547	108	ioucmd->sqe = sqe;
99f15d8d JA	109	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
	110	return 0;
	111	}
	112
	113	int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
	114	{
f2ccb5ae	115	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
99f15d8d JA	116	struct io_ring_ctx *ctx = req->ctx;
	117	struct file *file = req->file;
	118	int ret;
	119
03b3d6be	120	if (!file->f_op->uring_cmd)
99f15d8d JA	121	return -EOPNOTSUPP;
99f15d8d JA	122
2a584012 LC	123	ret = security_uring_cmd(ioucmd);
	124	if (ret)
	125	return ret;
	126
99f15d8d JA	127	if (ctx->flags & IORING_SETUP_SQE128)
	128	issue_flags \|= IO_URING_F_SQE128;
	129	if (ctx->flags & IORING_SETUP_CQE32)
	130	issue_flags \|= IO_URING_F_CQE32;
5756a3a7	131	if (ctx->flags & IORING_SETUP_IOPOLL) {
03b3d6be JA	132	if (!file->f_op->uring_cmd_iopoll)
03b3d6be JA	133	return -EOPNOTSUPP;
99f15d8d	134	issue_flags \|= IO_URING_F_IOPOLL;
5756a3a7 KJ	135	req->iopoll_completed = 0;
	136	WRITE_ONCE(ioucmd->cookie, NULL);
	137	}
99f15d8d	138
99f15d8d JA	139	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
	140	if (ret == -EAGAIN) {
	141	if (!req_has_async_data(req)) {
	142	if (io_alloc_async_data(req))
	143	return -ENOMEM;
	144	io_uring_cmd_prep_async(req);
	145	}
	146	return -EAGAIN;
	147	}
	148
	149	if (ret != -EIOCBQUEUED) {
3ed159c9 AG	150	if (ret < 0)
	151	req_set_fail(req);
	152	io_req_set_res(req, ret, 0);
a9c3eda7	153	return ret;
99f15d8d JA	154	}
	155
	156	return IOU_ISSUE_SKIP_COMPLETE;
	157	}
a9216fac AG	158
	159	int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
	160	struct iov_iter iter, void ioucmd)
	161	{
	162	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
	163
	164	return io_import_fixed(rw, iter, req->imu, ubuf, len);
	165	}
	166	EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);