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// SPDX-License-Identifier: GPL-2.0#include <linux/kernel.h>#include <linux/errno.h>#include <linux/file.h>#include <linux/io_uring/cmd.h>#include <linux/security.h>#include <linux/nospec.h> #include <uapi/linux/io_uring.h> #include "io_uring.h"#include "alloc_cache.h"#include "rsrc.h"#include "kbuf.h"#include "uring_cmd.h"#include "poll.h" void io_cmd_cache_free(const void *entry){	struct io_async_cmd *ac = (struct io_async_cmd *)entry; 	io_vec_free(&ac->vec);	kfree(ac);} static void io_req_uring_cleanup(struct io_kiocb *req, unsigned int issue_flags){	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);	struct io_async_cmd *ac = req->async_data; 	if (issue_flags & IO_URING_F_UNLOCKED)		return; 	io_alloc_cache_vec_kasan(&ac->vec);	if (ac->vec.nr > IO_VEC_CACHE_SOFT_CAP)		io_vec_free(&ac->vec); 	if (io_alloc_cache_put(&req->ctx->cmd_cache, ac)) {		ioucmd->sqe = NULL;		io_req_async_data_clear(req, REQ_F_NEED_CLEANUP);	}} void io_uring_cmd_cleanup(struct io_kiocb *req){	io_req_uring_cleanup(req, 0);} bool io_uring_try_cancel_uring_cmd(struct io_ring_ctx *ctx,				   struct io_uring_task *tctx, bool cancel_all){	struct hlist_node *tmp;	struct io_kiocb *req;	bool ret = false; 	lockdep_assert_held(&ctx->uring_lock); 	hlist_for_each_entry_safe(req, tmp, &ctx->cancelable_uring_cmd,			hash_node) {		struct io_uring_cmd *cmd = io_kiocb_to_cmd(req,				struct io_uring_cmd);		struct file *file = req->file; 		if (!cancel_all && req->tctx != tctx)			continue; 		if (cmd->flags & IORING_URING_CMD_CANCELABLE) {			file->f_op->uring_cmd(cmd, IO_URING_F_CANCEL |						   IO_URING_F_COMPLETE_DEFER);			ret = true;		}	}	io_submit_flush_completions(ctx);	return ret;} static void io_uring_cmd_del_cancelable(struct io_uring_cmd *cmd,		unsigned int issue_flags){	struct io_kiocb *req = cmd_to_io_kiocb(cmd);	struct io_ring_ctx *ctx = req->ctx; 	if (!(cmd->flags & IORING_URING_CMD_CANCELABLE))		return; 	cmd->flags &= ~IORING_URING_CMD_CANCELABLE;	io_ring_submit_lock(ctx, issue_flags);	hlist_del(&req->hash_node);	io_ring_submit_unlock(ctx, issue_flags);} /* * Mark this command as concelable, then io_uring_try_cancel_uring_cmd() * will try to cancel this issued command by sending ->uring_cmd() with * issue_flags of IO_URING_F_CANCEL. * * The command is guaranteed to not be done when calling ->uring_cmd() * with IO_URING_F_CANCEL, but it is driver's responsibility to deal * with race between io_uring canceling and normal completion. */void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,		unsigned int issue_flags){	struct io_kiocb *req = cmd_to_io_kiocb(cmd);	struct io_ring_ctx *ctx = req->ctx; 	/*	 * Doing cancelations on IOPOLL requests are not supported. Both	 * because they can't get canceled in the block stack, but also	 * because iopoll completion data overlaps with the hash_node used	 * for tracking.	 */	if (ctx->flags & IORING_SETUP_IOPOLL)		return; 	if (!(cmd->flags & IORING_URING_CMD_CANCELABLE)) {		cmd->flags |= IORING_URING_CMD_CANCELABLE;		io_ring_submit_lock(ctx, issue_flags);		hlist_add_head(&req->hash_node, &ctx->cancelable_uring_cmd);		io_ring_submit_unlock(ctx, issue_flags);	}}EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable); void __io_uring_cmd_do_in_task(struct io_uring_cmd *ioucmd,			io_req_tw_func_t task_work_cb,			unsigned flags){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 	if (WARN_ON_ONCE(req->flags & REQ_F_APOLL_MULTISHOT))		return; 	req->io_task_work.func = task_work_cb;	__io_req_task_work_add(req, flags);}EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task); static inline void io_req_set_cqe32_extra(struct io_kiocb *req,					  u64 extra1, u64 extra2){	req->big_cqe.extra1 = extra1;	req->big_cqe.extra2 = extra2;} /* * 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, s32 ret, u64 res2,		       unsigned issue_flags, bool is_cqe32){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 	if (WARN_ON_ONCE(req->flags & REQ_F_APOLL_MULTISHOT))		return; 	io_uring_cmd_del_cancelable(ioucmd, issue_flags); 	if (ret < 0)		req_set_fail(req); 	io_req_set_res(req, ret, 0);	if (is_cqe32) {		if (req->ctx->flags & IORING_SETUP_CQE_MIXED)			req->cqe.flags |= IORING_CQE_F_32;		io_req_set_cqe32_extra(req, res2, 0);	}	io_req_uring_cleanup(req, issue_flags);	if (req->ctx->flags & IORING_SETUP_IOPOLL) {		/* order with io_iopoll_req_issued() checking ->iopoll_complete */		smp_store_release(&req->iopoll_completed, 1);	} else if (issue_flags & IO_URING_F_COMPLETE_DEFER) {		if (WARN_ON_ONCE(issue_flags & IO_URING_F_UNLOCKED))			return;		io_req_complete_defer(req);	} else {		req->io_task_work.func = io_req_task_complete;		io_req_task_work_add(req);	}}EXPORT_SYMBOL_GPL(__io_uring_cmd_done); 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);	struct io_async_cmd *ac; 	if (sqe->__pad1)		return -EINVAL; 	ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags);	if (ioucmd->flags & ~IORING_URING_CMD_MASK)		return -EINVAL; 	if (ioucmd->flags & IORING_URING_CMD_FIXED) {		if (ioucmd->flags & IORING_URING_CMD_MULTISHOT)			return -EINVAL;		req->buf_index = READ_ONCE(sqe->buf_index);	} 	if (!!(ioucmd->flags & IORING_URING_CMD_MULTISHOT) !=	    !!(req->flags & REQ_F_BUFFER_SELECT))		return -EINVAL; 	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); 	ac = io_uring_alloc_async_data(&req->ctx->cmd_cache, req);	if (!ac)		return -ENOMEM;	ioucmd->sqe = sqe;	return 0;} /* * IORING_SETUP_SQE128 contexts allocate twice the normal SQE size for each * slot. */static inline size_t uring_sqe_size(struct io_kiocb *req){	if (req->ctx->flags & IORING_SETUP_SQE128 ||	    req->opcode == IORING_OP_URING_CMD128)		return 2 * sizeof(struct io_uring_sqe);	return sizeof(struct io_uring_sqe);} void io_uring_cmd_sqe_copy(struct io_kiocb *req){	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);	struct io_async_cmd *ac = req->async_data; 	/* Should not happen, as REQ_F_SQE_COPIED covers this */	if (WARN_ON_ONCE(ioucmd->sqe == ac->sqes))		return;	memcpy(ac->sqes, ioucmd->sqe, uring_sqe_size(req));	ioucmd->sqe = ac->sqes;} 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 ||	    req->opcode == IORING_OP_URING_CMD128)		issue_flags |= IO_URING_F_SQE128;	if (ctx->flags & (IORING_SETUP_CQE32 | IORING_SETUP_CQE_MIXED))		issue_flags |= IO_URING_F_CQE32;	if (io_is_compat(ctx))		issue_flags |= IO_URING_F_COMPAT;	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;		if (ctx->flags & IORING_SETUP_HYBRID_IOPOLL) {			/* make sure every req only blocks once */			req->flags &= ~REQ_F_IOPOLL_STATE;			req->iopoll_start = ktime_get_ns();		}	} 	ret = file->f_op->uring_cmd(ioucmd, issue_flags);	if (ioucmd->flags & IORING_URING_CMD_MULTISHOT) {		if (ret >= 0)			return IOU_ISSUE_SKIP_COMPLETE;	}	if (ret == -EAGAIN) {		ioucmd->flags |= IORING_URING_CMD_REISSUE;		return ret;	}	if (ret == -EIOCBQUEUED)		return ret;	if (ret < 0)		req_set_fail(req);	io_req_uring_cleanup(req, issue_flags);	io_req_set_res(req, ret, 0);	return IOU_COMPLETE;} int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,			      struct iov_iter *iter,			      struct io_uring_cmd *ioucmd,			      unsigned int issue_flags){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 	if (WARN_ON_ONCE(!(ioucmd->flags & IORING_URING_CMD_FIXED)))		return -EINVAL; 	return io_import_reg_buf(req, iter, ubuf, len, rw, issue_flags);}EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,				  const struct iovec __user *uvec,				  size_t uvec_segs,				  int ddir, struct iov_iter *iter,				  unsigned issue_flags){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);	struct io_async_cmd *ac = req->async_data;	int ret; 	if (WARN_ON_ONCE(!(ioucmd->flags & IORING_URING_CMD_FIXED)))		return -EINVAL; 	ret = io_prep_reg_iovec(req, &ac->vec, uvec, uvec_segs);	if (ret)		return ret; 	return io_import_reg_vec(ddir, iter, req, &ac->vec, uvec_segs,				 issue_flags);}EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed_vec); void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 	io_req_queue_iowq(req);} int io_cmd_poll_multishot(struct io_uring_cmd *cmd,			  unsigned int issue_flags, __poll_t mask){	struct io_kiocb *req = cmd_to_io_kiocb(cmd);	int ret; 	if (likely(req->flags & REQ_F_APOLL_MULTISHOT))		return 0; 	req->flags |= REQ_F_APOLL_MULTISHOT;	mask &= ~EPOLLONESHOT; 	ret = io_arm_apoll(req, issue_flags, mask);	return ret == IO_APOLL_OK ? -EIOCBQUEUED : -ECANCELED;} bool io_uring_cmd_post_mshot_cqe32(struct io_uring_cmd *cmd,				   unsigned int issue_flags,				   struct io_uring_cqe cqe[2]){	struct io_kiocb *req = cmd_to_io_kiocb(cmd); 	if (WARN_ON_ONCE(!(issue_flags & IO_URING_F_MULTISHOT)))		return false;	return io_req_post_cqe32(req, cqe);} /* * Work with io_uring_mshot_cmd_post_cqe() together for committing the * provided buffer upfront */struct io_br_sel io_uring_cmd_buffer_select(struct io_uring_cmd *ioucmd,					    unsigned buf_group, size_t *len,					    unsigned int issue_flags){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 	if (!(ioucmd->flags & IORING_URING_CMD_MULTISHOT))		return (struct io_br_sel) { .val = -EINVAL }; 	if (WARN_ON_ONCE(!io_do_buffer_select(req)))		return (struct io_br_sel) { .val = -EINVAL }; 	return io_buffer_select(req, len, buf_group, issue_flags);}EXPORT_SYMBOL_GPL(io_uring_cmd_buffer_select); /* * Return true if this multishot uring_cmd needs to be completed, otherwise * the event CQE is posted successfully. * * This function must use `struct io_br_sel` returned from * io_uring_cmd_buffer_select() for committing the buffer in the same * uring_cmd submission context. */bool io_uring_mshot_cmd_post_cqe(struct io_uring_cmd *ioucmd,				 struct io_br_sel *sel, unsigned int issue_flags){	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);	unsigned int cflags = 0; 	if (!(ioucmd->flags & IORING_URING_CMD_MULTISHOT))		return true; 	if (sel->val > 0) {		cflags = io_put_kbuf(req, sel->val, sel->buf_list);		if (io_req_post_cqe(req, sel->val, cflags | IORING_CQE_F_MORE))			return false;	} 	io_kbuf_recycle(req, sel->buf_list, issue_flags);	if (sel->val < 0)		req_set_fail(req);	io_req_set_res(req, sel->val, cflags);	return true;}EXPORT_SYMBOL_GPL(io_uring_mshot_cmd_post_cqe);