Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 397 insertions, 0 deletions

diff --git a/io_uring/io_uring.h b/io_uring/io_uring.h
new file mode 100644
index 0000000000..d2bad1df34
--- /dev/null
+++ b/io_uring/io_uring.h
@@ -0,0 +1,397 @@
+#ifndef IOU_CORE_H
+#define IOU_CORE_H
+
+#include <linux/errno.h>
+#include <linux/lockdep.h>
+#include <linux/resume_user_mode.h>
+#include <linux/kasan.h>
+#include <linux/io_uring_types.h>
+#include <uapi/linux/eventpoll.h>
+#include "io-wq.h"
+#include "slist.h"
+#include "filetable.h"
+
+#ifndef CREATE_TRACE_POINTS
+#include <trace/events/io_uring.h>
+#endif
+
+enum {
+	/*
+	 * A hint to not wake right away but delay until there are enough of
+	 * tw's queued to match the number of CQEs the task is waiting for.
+	 *
+	 * Must not be used wirh requests generating more than one CQE.
+	 * It's also ignored unless IORING_SETUP_DEFER_TASKRUN is set.
+	 */
+	IOU_F_TWQ_LAZY_WAKE			= 1,
+};
+
+enum {
+	IOU_OK			= 0,
+	IOU_ISSUE_SKIP_COMPLETE	= -EIOCBQUEUED,
+
+	/*
+	 * Intended only when both IO_URING_F_MULTISHOT is passed
+	 * to indicate to the poll runner that multishot should be
+	 * removed and the result is set on req->cqe.res.
+	 */
+	IOU_STOP_MULTISHOT	= -ECANCELED,
+};
+
+bool io_cqe_cache_refill(struct io_ring_ctx *ctx, bool overflow);
+void io_req_cqe_overflow(struct io_kiocb *req);
+int io_run_task_work_sig(struct io_ring_ctx *ctx);
+void io_req_defer_failed(struct io_kiocb *req, s32 res);
+void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags);
+bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags);
+bool io_fill_cqe_req_aux(struct io_kiocb *req, bool defer, s32 res, u32 cflags);
+void __io_commit_cqring_flush(struct io_ring_ctx *ctx);
+
+struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages);
+
+struct file *io_file_get_normal(struct io_kiocb *req, int fd);
+struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
+			       unsigned issue_flags);
+
+void __io_req_task_work_add(struct io_kiocb *req, unsigned flags);
+bool io_is_uring_fops(struct file *file);
+bool io_alloc_async_data(struct io_kiocb *req);
+void io_req_task_queue(struct io_kiocb *req);
+void io_queue_iowq(struct io_kiocb *req, struct io_tw_state *ts_dont_use);
+void io_req_task_complete(struct io_kiocb *req, struct io_tw_state *ts);
+void io_req_task_queue_fail(struct io_kiocb *req, int ret);
+void io_req_task_submit(struct io_kiocb *req, struct io_tw_state *ts);
+void tctx_task_work(struct callback_head *cb);
+__cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
+int io_uring_alloc_task_context(struct task_struct *task,
+				struct io_ring_ctx *ctx);
+
+int io_ring_add_registered_file(struct io_uring_task *tctx, struct file *file,
+				     int start, int end);
+
+int io_poll_issue(struct io_kiocb *req, struct io_tw_state *ts);
+int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr);
+int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin);
+void __io_submit_flush_completions(struct io_ring_ctx *ctx);
+int io_req_prep_async(struct io_kiocb *req);
+
+struct io_wq_work *io_wq_free_work(struct io_wq_work *work);
+void io_wq_submit_work(struct io_wq_work *work);
+
+void io_free_req(struct io_kiocb *req);
+void io_queue_next(struct io_kiocb *req);
+void io_task_refs_refill(struct io_uring_task *tctx);
+bool __io_alloc_req_refill(struct io_ring_ctx *ctx);
+
+bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
+			bool cancel_all);
+
+void *io_mem_alloc(size_t size);
+void io_mem_free(void *ptr);
+
+#if defined(CONFIG_PROVE_LOCKING)
+static inline void io_lockdep_assert_cq_locked(struct io_ring_ctx *ctx)
+{
+	lockdep_assert(in_task());
+
+	if (ctx->flags & IORING_SETUP_IOPOLL) {
+		lockdep_assert_held(&ctx->uring_lock);
+	} else if (!ctx->task_complete) {
+		lockdep_assert_held(&ctx->completion_lock);
+	} else if (ctx->submitter_task) {
+		/*
+		 * ->submitter_task may be NULL and we can still post a CQE,
+		 * if the ring has been setup with IORING_SETUP_R_DISABLED.
+		 * Not from an SQE, as those cannot be submitted, but via
+		 * updating tagged resources.
+		 */
+		if (ctx->submitter_task->flags & PF_EXITING)
+			lockdep_assert(current_work());
+		else
+			lockdep_assert(current == ctx->submitter_task);
+	}
+}
+#else
+static inline void io_lockdep_assert_cq_locked(struct io_ring_ctx *ctx)
+{
+}
+#endif
+
+static inline void io_req_task_work_add(struct io_kiocb *req)
+{
+	__io_req_task_work_add(req, 0);
+}
+
+#define io_for_each_link(pos, head) \
+	for (pos = (head); pos; pos = pos->link)
+
+static inline bool io_get_cqe_overflow(struct io_ring_ctx *ctx,
+					struct io_uring_cqe **ret,
+					bool overflow)
+{
+	io_lockdep_assert_cq_locked(ctx);
+
+	if (unlikely(ctx->cqe_cached >= ctx->cqe_sentinel)) {
+		if (unlikely(!io_cqe_cache_refill(ctx, overflow)))
+			return false;
+	}
+	*ret = ctx->cqe_cached;
+	ctx->cached_cq_tail++;
+	ctx->cqe_cached++;
+	if (ctx->flags & IORING_SETUP_CQE32)
+		ctx->cqe_cached++;
+	return true;
+}
+
+static inline bool io_get_cqe(struct io_ring_ctx *ctx, struct io_uring_cqe **ret)
+{
+	return io_get_cqe_overflow(ctx, ret, false);
+}
+
+static __always_inline bool io_fill_cqe_req(struct io_ring_ctx *ctx,
+					    struct io_kiocb *req)
+{
+	struct io_uring_cqe *cqe;
+
+	/*
+	 * If we can't get a cq entry, userspace overflowed the
+	 * submission (by quite a lot). Increment the overflow count in
+	 * the ring.
+	 */
+	if (unlikely(!io_get_cqe(ctx, &cqe)))
+		return false;
+
+	if (trace_io_uring_complete_enabled())
+		trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
+					req->cqe.res, req->cqe.flags,
+					req->big_cqe.extra1, req->big_cqe.extra2);
+
+	memcpy(cqe, &req->cqe, sizeof(*cqe));
+	if (ctx->flags & IORING_SETUP_CQE32) {
+		memcpy(cqe->big_cqe, &req->big_cqe, sizeof(*cqe));
+		memset(&req->big_cqe, 0, sizeof(req->big_cqe));
+	}
+	return true;
+}
+
+static inline void req_set_fail(struct io_kiocb *req)
+{
+	req->flags |= REQ_F_FAIL;
+	if (req->flags & REQ_F_CQE_SKIP) {
+		req->flags &= ~REQ_F_CQE_SKIP;
+		req->flags |= REQ_F_SKIP_LINK_CQES;
+	}
+}
+
+static inline void io_req_set_res(struct io_kiocb *req, s32 res, u32 cflags)
+{
+	req->cqe.res = res;
+	req->cqe.flags = cflags;
+}
+
+static inline bool req_has_async_data(struct io_kiocb *req)
+{
+	return req->flags & REQ_F_ASYNC_DATA;
+}
+
+static inline void io_put_file(struct io_kiocb *req)
+{
+	if (!(req->flags & REQ_F_FIXED_FILE) && req->file)
+		fput(req->file);
+}
+
+static inline void io_ring_submit_unlock(struct io_ring_ctx *ctx,
+					 unsigned issue_flags)
+{
+	lockdep_assert_held(&ctx->uring_lock);
+	if (issue_flags & IO_URING_F_UNLOCKED)
+		mutex_unlock(&ctx->uring_lock);
+}
+
+static inline void io_ring_submit_lock(struct io_ring_ctx *ctx,
+				       unsigned issue_flags)
+{
+	/*
+	 * "Normal" inline submissions always hold the uring_lock, since we
+	 * grab it from the system call. Same is true for the SQPOLL offload.
+	 * The only exception is when we've detached the request and issue it
+	 * from an async worker thread, grab the lock for that case.
+	 */
+	if (issue_flags & IO_URING_F_UNLOCKED)
+		mutex_lock(&ctx->uring_lock);
+	lockdep_assert_held(&ctx->uring_lock);
+}
+
+static inline void io_commit_cqring(struct io_ring_ctx *ctx)
+{
+	/* order cqe stores with ring update */
+	smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
+}
+
+static inline void io_poll_wq_wake(struct io_ring_ctx *ctx)
+{
+	if (wq_has_sleeper(&ctx->poll_wq))
+		__wake_up(&ctx->poll_wq, TASK_NORMAL, 0,
+				poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
+}
+
+static inline void io_cqring_wake(struct io_ring_ctx *ctx)
+{
+	/*
+	 * Trigger waitqueue handler on all waiters on our waitqueue. This
+	 * won't necessarily wake up all the tasks, io_should_wake() will make
+	 * that decision.
+	 *
+	 * Pass in EPOLLIN|EPOLL_URING_WAKE as the poll wakeup key. The latter
+	 * set in the mask so that if we recurse back into our own poll
+	 * waitqueue handlers, we know we have a dependency between eventfd or
+	 * epoll and should terminate multishot poll at that point.
+	 */
+	if (wq_has_sleeper(&ctx->cq_wait))
+		__wake_up(&ctx->cq_wait, TASK_NORMAL, 0,
+				poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
+}
+
+static inline bool io_sqring_full(struct io_ring_ctx *ctx)
+{
+	struct io_rings *r = ctx->rings;
+
+	return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
+}
+
+static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
+{
+	struct io_rings *rings = ctx->rings;
+	unsigned int entries;
+
+	/* make sure SQ entry isn't read before tail */
+	entries = smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
+	return min(entries, ctx->sq_entries);
+}
+
+static inline int io_run_task_work(void)
+{
+	/*
+	 * Always check-and-clear the task_work notification signal. With how
+	 * signaling works for task_work, we can find it set with nothing to
+	 * run. We need to clear it for that case, like get_signal() does.
+	 */
+	if (test_thread_flag(TIF_NOTIFY_SIGNAL))
+		clear_notify_signal();
+	/*
+	 * PF_IO_WORKER never returns to userspace, so check here if we have
+	 * notify work that needs processing.
+	 */
+	if (current->flags & PF_IO_WORKER &&
+	    test_thread_flag(TIF_NOTIFY_RESUME)) {
+		__set_current_state(TASK_RUNNING);
+		resume_user_mode_work(NULL);
+	}
+	if (task_work_pending(current)) {
+		__set_current_state(TASK_RUNNING);
+		task_work_run();
+		return 1;
+	}
+
+	return 0;
+}
+
+static inline bool io_task_work_pending(struct io_ring_ctx *ctx)
+{
+	return task_work_pending(current) || !wq_list_empty(&ctx->work_llist);
+}
+
+static inline void io_tw_lock(struct io_ring_ctx *ctx, struct io_tw_state *ts)
+{
+	if (!ts->locked) {
+		mutex_lock(&ctx->uring_lock);
+		ts->locked = true;
+	}
+}
+
+/*
+ * Don't complete immediately but use deferred completion infrastructure.
+ * Protected by ->uring_lock and can only be used either with
+ * IO_URING_F_COMPLETE_DEFER or inside a tw handler holding the mutex.
+ */
+static inline void io_req_complete_defer(struct io_kiocb *req)
+	__must_hold(&req->ctx->uring_lock)
+{
+	struct io_submit_state *state = &req->ctx->submit_state;
+
+	lockdep_assert_held(&req->ctx->uring_lock);
+
+	wq_list_add_tail(&req->comp_list, &state->compl_reqs);
+}
+
+static inline void io_commit_cqring_flush(struct io_ring_ctx *ctx)
+{
+	if (unlikely(ctx->off_timeout_used || ctx->drain_active ||
+		     ctx->has_evfd || ctx->poll_activated))
+		__io_commit_cqring_flush(ctx);
+}
+
+static inline void io_get_task_refs(int nr)
+{
+	struct io_uring_task *tctx = current->io_uring;
+
+	tctx->cached_refs -= nr;
+	if (unlikely(tctx->cached_refs < 0))
+		io_task_refs_refill(tctx);
+}
+
+static inline bool io_req_cache_empty(struct io_ring_ctx *ctx)
+{
+	return !ctx->submit_state.free_list.next;
+}
+
+extern struct kmem_cache *req_cachep;
+
+static inline struct io_kiocb *io_extract_req(struct io_ring_ctx *ctx)
+{
+	struct io_kiocb *req;
+
+	req = container_of(ctx->submit_state.free_list.next, struct io_kiocb, comp_list);
+	wq_stack_extract(&ctx->submit_state.free_list);
+	return req;
+}
+
+static inline bool io_alloc_req(struct io_ring_ctx *ctx, struct io_kiocb **req)
+{
+	if (unlikely(io_req_cache_empty(ctx))) {
+		if (!__io_alloc_req_refill(ctx))
+			return false;
+	}
+	*req = io_extract_req(ctx);
+	return true;
+}
+
+static inline bool io_allowed_defer_tw_run(struct io_ring_ctx *ctx)
+{
+	return likely(ctx->submitter_task == current);
+}
+
+static inline bool io_allowed_run_tw(struct io_ring_ctx *ctx)
+{
+	return likely(!(ctx->flags & IORING_SETUP_DEFER_TASKRUN) ||
+		      ctx->submitter_task == current);
+}
+
+static inline void io_req_queue_tw_complete(struct io_kiocb *req, s32 res)
+{
+	io_req_set_res(req, res, 0);
+	req->io_task_work.func = io_req_task_complete;
+	io_req_task_work_add(req);
+}
+
+/*
+ * IORING_SETUP_SQE128 contexts allocate twice the normal SQE size for each
+ * slot.
+ */
+static inline size_t uring_sqe_size(struct io_ring_ctx *ctx)
+{
+	if (ctx->flags & IORING_SETUP_SQE128)
+		return 2 * sizeof(struct io_uring_sqe);
+	return sizeof(struct io_uring_sqe);
+}
+#endif