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1// SPDX-License-Identifier: GPL-2.02#include <linux/kernel.h>3#include <linux/errno.h>4#include <linux/file.h>5#include <linux/io_uring/cmd.h>6#include <linux/io_uring/net.h>7#include <linux/security.h>8#include <linux/nospec.h>9#include <net/sock.h>10 11#include <uapi/linux/io_uring.h>12#include <asm/ioctls.h>13 14#include "io_uring.h"15#include "alloc_cache.h"16#include "rsrc.h"17#include "uring_cmd.h"18 19static struct uring_cache *io_uring_async_get(struct io_kiocb *req)20{21	struct io_ring_ctx *ctx = req->ctx;22	struct uring_cache *cache;23 24	cache = io_alloc_cache_get(&ctx->uring_cache);25	if (cache) {26		req->flags |= REQ_F_ASYNC_DATA;27		req->async_data = cache;28		return cache;29	}30	if (!io_alloc_async_data(req))31		return req->async_data;32	return NULL;33}34 35static void io_req_uring_cleanup(struct io_kiocb *req, unsigned int issue_flags)36{37	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);38	struct uring_cache *cache = req->async_data;39 40	if (issue_flags & IO_URING_F_UNLOCKED)41		return;42	if (io_alloc_cache_put(&req->ctx->uring_cache, cache)) {43		ioucmd->sqe = NULL;44		req->async_data = NULL;45		req->flags &= ~REQ_F_ASYNC_DATA;46	}47}48 49bool io_uring_try_cancel_uring_cmd(struct io_ring_ctx *ctx,50				   struct task_struct *task, bool cancel_all)51{52	struct hlist_node *tmp;53	struct io_kiocb *req;54	bool ret = false;55 56	lockdep_assert_held(&ctx->uring_lock);57 58	hlist_for_each_entry_safe(req, tmp, &ctx->cancelable_uring_cmd,59			hash_node) {60		struct io_uring_cmd *cmd = io_kiocb_to_cmd(req,61				struct io_uring_cmd);62		struct file *file = req->file;63 64		if (!cancel_all && req->task != task)65			continue;66 67		if (cmd->flags & IORING_URING_CMD_CANCELABLE) {68			/* ->sqe isn't available if no async data */69			if (!req_has_async_data(req))70				cmd->sqe = NULL;71			file->f_op->uring_cmd(cmd, IO_URING_F_CANCEL |72						   IO_URING_F_COMPLETE_DEFER);73			ret = true;74		}75	}76	io_submit_flush_completions(ctx);77	return ret;78}79 80static HWJS_SUSPENDS void io_uring_cmd_del_cancelable(struct io_uring_cmd *cmd,81		unsigned int issue_flags)82{83	struct io_kiocb *req = cmd_to_io_kiocb(cmd);84	struct io_ring_ctx *ctx = req->ctx;85 86	if (!(cmd->flags & IORING_URING_CMD_CANCELABLE))87		return;88 89	cmd->flags &= ~IORING_URING_CMD_CANCELABLE;90	io_ring_submit_lock(ctx, issue_flags);91	hlist_del(&req->hash_node);92	io_ring_submit_unlock(ctx, issue_flags);93}94 95/*96 * Mark this command as concelable, then io_uring_try_cancel_uring_cmd()97 * will try to cancel this issued command by sending ->uring_cmd() with98 * issue_flags of IO_URING_F_CANCEL.99 *100 * The command is guaranteed to not be done when calling ->uring_cmd()101 * with IO_URING_F_CANCEL, but it is driver's responsibility to deal102 * with race between io_uring canceling and normal completion.103 */104void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,105		unsigned int issue_flags)106{107	struct io_kiocb *req = cmd_to_io_kiocb(cmd);108	struct io_ring_ctx *ctx = req->ctx;109 110	if (!(cmd->flags & IORING_URING_CMD_CANCELABLE)) {111		cmd->flags |= IORING_URING_CMD_CANCELABLE;112		io_ring_submit_lock(ctx, issue_flags);113		hlist_add_head(&req->hash_node, &ctx->cancelable_uring_cmd);114		io_ring_submit_unlock(ctx, issue_flags);115	}116}117EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable);118 119static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)120{121	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);122 123	/* task_work executor checks the deffered list completion */124	ioucmd->task_work_cb(ioucmd, IO_URING_F_COMPLETE_DEFER);125}126 127void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,128			void (*task_work_cb)(struct io_uring_cmd *, unsigned),129			unsigned flags)130{131	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);132 133	ioucmd->task_work_cb = task_work_cb;134	req->io_task_work.func = io_uring_cmd_work;135	__io_req_task_work_add(req, flags);136}137EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task);138 139static inline void io_req_set_cqe32_extra(struct io_kiocb *req,140					  u64 extra1, u64 extra2)141{142	req->big_cqe.extra1 = extra1;143	req->big_cqe.extra2 = extra2;144}145 146/*147 * Called by consumers of io_uring_cmd, if they originally returned148 * -EIOCBQUEUED upon receiving the command.149 */150void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,151		       unsigned issue_flags)152{153	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);154 155	io_uring_cmd_del_cancelable(ioucmd, issue_flags);156 157	if (ret < 0)158		req_set_fail(req);159 160	io_req_set_res(req, ret, 0);161	if (req->ctx->flags & IORING_SETUP_CQE32)162		io_req_set_cqe32_extra(req, res2, 0);163	io_req_uring_cleanup(req, issue_flags);164	if (req->ctx->flags & IORING_SETUP_IOPOLL) {165		/* order with io_iopoll_req_issued() checking ->iopoll_complete */166		smp_store_release(&req->iopoll_completed, 1);167	} else if (issue_flags & IO_URING_F_COMPLETE_DEFER) {168		if (WARN_ON_ONCE(issue_flags & IO_URING_F_UNLOCKED))169			return;170		io_req_complete_defer(req);171	} else {172		req->io_task_work.func = io_req_task_complete;173		io_req_task_work_add(req);174	}175}176EXPORT_SYMBOL_GPL(io_uring_cmd_done);177 178static int io_uring_cmd_prep_setup(struct io_kiocb *req,179				   const struct io_uring_sqe *sqe)180{181	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);182	struct uring_cache *cache;183 184	cache = io_uring_async_get(req);185	if (unlikely(!cache))186		return -ENOMEM;187 188	if (!(req->flags & REQ_F_FORCE_ASYNC)) {189		/* defer memcpy until we need it */190		ioucmd->sqe = sqe;191		return 0;192	}193 194	memcpy(req->async_data, sqe, uring_sqe_size(req->ctx));195	ioucmd->sqe = req->async_data;196	return 0;197}198 199int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)200{201	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);202 203	if (sqe->__pad1)204		return -EINVAL;205 206	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);207	if (ioucmd->flags & ~IORING_URING_CMD_MASK)208		return -EINVAL;209 210	if (ioucmd->flags & IORING_URING_CMD_FIXED) {211		struct io_ring_ctx *ctx = req->ctx;212		u16 index;213 214		req->buf_index = READ_ONCE(sqe->buf_index);215		if (unlikely(req->buf_index >= ctx->nr_user_bufs))216			return -EFAULT;217		index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);218		req->imu = ctx->user_bufs[index];219		io_req_set_rsrc_node(req, ctx, 0);220	}221	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);222 223	return io_uring_cmd_prep_setup(req, sqe);224}225 226int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)227{228	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);229	struct io_ring_ctx *ctx = req->ctx;230	struct file *file = req->file;231	int ret;232 233	if (!file->f_op->uring_cmd)234		return -EOPNOTSUPP;235 236	ret = security_uring_cmd(ioucmd);237	if (ret)238		return ret;239 240	if (ctx->flags & IORING_SETUP_SQE128)241		issue_flags |= IO_URING_F_SQE128;242	if (ctx->flags & IORING_SETUP_CQE32)243		issue_flags |= IO_URING_F_CQE32;244	if (ctx->compat)245		issue_flags |= IO_URING_F_COMPAT;246	if (ctx->flags & IORING_SETUP_IOPOLL) {247		if (!file->f_op->uring_cmd_iopoll)248			return -EOPNOTSUPP;249		issue_flags |= IO_URING_F_IOPOLL;250		req->iopoll_completed = 0;251	}252 253	ret = file->f_op->uring_cmd(ioucmd, issue_flags);254	if (ret == -EAGAIN) {255		struct uring_cache *cache = req->async_data;256 257		if (ioucmd->sqe != (void *) cache)258			memcpy(cache, ioucmd->sqe, uring_sqe_size(req->ctx));259		return -EAGAIN;260	} else if (ret == -EIOCBQUEUED) {261		return -EIOCBQUEUED;262	}263 264	if (ret < 0)265		req_set_fail(req);266	io_req_uring_cleanup(req, issue_flags);267	io_req_set_res(req, ret, 0);268	return IOU_OK;269}270 271int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,272			      struct iov_iter *iter, void *ioucmd)273{274	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);275 276	return io_import_fixed(rw, iter, req->imu, ubuf, len);277}278EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed);279 280void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd)281{282	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);283 284	io_req_queue_iowq(req);285}286 287static inline int io_uring_cmd_getsockopt(struct socket *sock,288					  struct io_uring_cmd *cmd,289					  unsigned int issue_flags)290{291	bool compat = !!(issue_flags & IO_URING_F_COMPAT);292	int optlen, optname, level, err;293	void __user *optval;294 295	level = READ_ONCE(cmd->sqe->level);296	if (level != SOL_SOCKET)297		return -EOPNOTSUPP;298 299	optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));300	optname = READ_ONCE(cmd->sqe->optname);301	optlen = READ_ONCE(cmd->sqe->optlen);302 303	err = do_sock_getsockopt(sock, compat, level, optname,304				 USER_SOCKPTR(optval),305				 KERNEL_SOCKPTR(&optlen));306	if (err)307		return err;308 309	/* On success, return optlen */310	return optlen;311}312 313static inline int io_uring_cmd_setsockopt(struct socket *sock,314					  struct io_uring_cmd *cmd,315					  unsigned int issue_flags)316{317	bool compat = !!(issue_flags & IO_URING_F_COMPAT);318	int optname, optlen, level;319	void __user *optval;320	sockptr_t optval_s;321 322	optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval));323	optname = READ_ONCE(cmd->sqe->optname);324	optlen = READ_ONCE(cmd->sqe->optlen);325	level = READ_ONCE(cmd->sqe->level);326	optval_s = USER_SOCKPTR(optval);327 328	return do_sock_setsockopt(sock, compat, level, optname, optval_s,329				  optlen);330}331 332#if defined(CONFIG_NET)333int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags)334{335	struct socket *sock = cmd->file->private_data;336	struct sock *sk = sock->sk;337	struct proto *prot = READ_ONCE(sk->sk_prot);338	int ret, arg = 0;339 340	if (!prot || !prot->ioctl)341		return -EOPNOTSUPP;342 343	switch (cmd->sqe->cmd_op) {344	case SOCKET_URING_OP_SIOCINQ:345		ret = prot->ioctl(sk, SIOCINQ, &arg);346		if (ret)347			return ret;348		return arg;349	case SOCKET_URING_OP_SIOCOUTQ:350		ret = prot->ioctl(sk, SIOCOUTQ, &arg);351		if (ret)352			return ret;353		return arg;354	case SOCKET_URING_OP_GETSOCKOPT:355		return io_uring_cmd_getsockopt(sock, cmd, issue_flags);356	case SOCKET_URING_OP_SETSOCKOPT:357		return io_uring_cmd_setsockopt(sock, cmd, issue_flags);358	default:359		return -EOPNOTSUPP;360	}361}362EXPORT_SYMBOL_GPL(io_uring_cmd_sock);363#endif364