Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 755 insertions, 0 deletions

diff --git a/io_uring/timeout.c b/io_uring/timeout.c
new file mode 100644
index 000000000..c4dd26cf3
--- /dev/null
+++ b/io_uring/timeout.c
@@ -0,0 +1,755 @@
+// 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/time_namespace.h>
+
+#include <trace/events/io_uring.h>
+
+#include <uapi/linux/io_uring.h>
+
+#include "io_uring.h"
+#include "refs.h"
+#include "cancel.h"
+#include "timeout.h"
+
+struct io_timeout {
+	struct file			*file;
+	u32				off;
+	u32				target_seq;
+	u32				repeats;
+	struct list_head		list;
+	/* head of the link, used by linked timeouts only */
+	struct io_kiocb			*head;
+	/* for linked completions */
+	struct io_kiocb			*prev;
+};
+
+struct io_timeout_rem {
+	struct file			*file;
+	u64				addr;
+
+	/* timeout update */
+	ktime_t				time;
+	u32				flags;
+	bool				ltimeout;
+};
+
+static clockid_t io_flags_to_clock(unsigned flags)
+{
+	switch (flags & IORING_TIMEOUT_CLOCK_MASK) {
+	case IORING_TIMEOUT_BOOTTIME:
+		return CLOCK_BOOTTIME;
+	case IORING_TIMEOUT_REALTIME:
+		return CLOCK_REALTIME;
+	default:
+		/* can't happen, vetted at prep time */
+		WARN_ON_ONCE(1);
+		fallthrough;
+	case 0:
+		return CLOCK_MONOTONIC;
+	}
+}
+
+static int io_parse_user_time(ktime_t *time, u64 arg, unsigned flags)
+{
+	struct timespec64 ts;
+
+	if (flags & IORING_TIMEOUT_IMMEDIATE_ARG) {
+		*time = ns_to_ktime(arg);
+		if (*time < 0)
+			return -EINVAL;
+		goto out;
+	}
+
+	if (get_timespec64(&ts, u64_to_user_ptr(arg)))
+		return -EFAULT;
+	if (ts.tv_sec < 0 || ts.tv_nsec < 0)
+		return -EINVAL;
+	*time = timespec64_to_ktime(ts);
+out:
+	if (flags & IORING_TIMEOUT_ABS)
+		*time = timens_ktime_to_host(io_flags_to_clock(flags), *time);
+	return 0;
+}
+
+static struct io_kiocb *__io_disarm_linked_timeout(struct io_kiocb *req,
+						   struct io_kiocb *link);
+
+static inline bool io_is_timeout_noseq(struct io_kiocb *req)
+{
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_timeout_data *data = req->async_data;
+
+	return !timeout->off || data->flags & IORING_TIMEOUT_MULTISHOT;
+}
+
+static inline void io_put_req(struct io_kiocb *req)
+{
+	if (req_ref_put_and_test(req)) {
+		io_queue_next(req);
+		io_free_req(req);
+	}
+}
+
+static inline bool io_timeout_finish(struct io_timeout *timeout,
+				     struct io_timeout_data *data)
+{
+	if (!(data->flags & IORING_TIMEOUT_MULTISHOT))
+		return true;
+
+	if (!timeout->off || (timeout->repeats && --timeout->repeats))
+		return false;
+
+	return true;
+}
+
+static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer);
+
+static void io_timeout_complete(struct io_tw_req tw_req, io_tw_token_t tw)
+{
+	struct io_kiocb *req = tw_req.req;
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_timeout_data *data = req->async_data;
+	struct io_ring_ctx *ctx = req->ctx;
+
+	if (!io_timeout_finish(timeout, data)) {
+		if (io_req_post_cqe(req, -ETIME, IORING_CQE_F_MORE)) {
+			/* re-arm timer */
+			raw_spin_lock_irq(&ctx->timeout_lock);
+			list_add(&timeout->list, ctx->timeout_list.prev);
+			hrtimer_start(&data->timer, data->time, data->mode);
+			raw_spin_unlock_irq(&ctx->timeout_lock);
+			return;
+		}
+	}
+
+	io_req_task_complete(tw_req, tw);
+}
+
+static __cold bool io_flush_killed_timeouts(struct list_head *list, int err)
+{
+	if (list_empty(list))
+		return false;
+
+	while (!list_empty(list)) {
+		struct io_timeout *timeout;
+		struct io_kiocb *req;
+
+		timeout = list_first_entry(list, struct io_timeout, list);
+		list_del_init(&timeout->list);
+		req = cmd_to_io_kiocb(timeout);
+		if (err)
+			req_set_fail(req);
+		io_req_queue_tw_complete(req, err);
+	}
+
+	return true;
+}
+
+static void io_kill_timeout(struct io_kiocb *req, struct list_head *list)
+	__must_hold(&req->ctx->timeout_lock)
+{
+	struct io_timeout_data *io = req->async_data;
+
+	if (hrtimer_try_to_cancel(&io->timer) != -1) {
+		struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+
+		atomic_set(&req->ctx->cq_timeouts,
+			atomic_read(&req->ctx->cq_timeouts) + 1);
+		list_move_tail(&timeout->list, list);
+	}
+}
+
+__cold void io_flush_timeouts(struct io_ring_ctx *ctx)
+{
+	struct io_timeout *timeout, *tmp;
+	LIST_HEAD(list);
+	u32 seq;
+
+	raw_spin_lock_irq(&ctx->timeout_lock);
+	seq = READ_ONCE(ctx->cached_cq_tail) - atomic_read(&ctx->cq_timeouts);
+
+	list_for_each_entry_safe(timeout, tmp, &ctx->timeout_list, list) {
+		struct io_kiocb *req = cmd_to_io_kiocb(timeout);
+		u32 events_needed, events_got;
+
+		if (io_is_timeout_noseq(req))
+			break;
+
+		/*
+		 * Since seq can easily wrap around over time, subtract
+		 * the last seq at which timeouts were flushed before comparing.
+		 * Assuming not more than 2^31-1 events have happened since,
+		 * these subtractions won't have wrapped, so we can check if
+		 * target is in [last_seq, current_seq] by comparing the two.
+		 */
+		events_needed = timeout->target_seq - ctx->cq_last_tm_flush;
+		events_got = seq - ctx->cq_last_tm_flush;
+		if (events_got < events_needed)
+			break;
+
+		io_kill_timeout(req, &list);
+	}
+	ctx->cq_last_tm_flush = seq;
+	raw_spin_unlock_irq(&ctx->timeout_lock);
+	io_flush_killed_timeouts(&list, 0);
+}
+
+static void io_req_tw_fail_links(struct io_tw_req tw_req, io_tw_token_t tw)
+{
+	struct io_kiocb *link = tw_req.req;
+
+	io_tw_lock(link->ctx, tw);
+	while (link) {
+		struct io_kiocb *nxt = link->link;
+		long res = -ECANCELED;
+
+		if (link->flags & REQ_F_FAIL)
+			res = link->cqe.res;
+		link->link = NULL;
+		io_req_set_res(link, res, 0);
+		io_req_task_complete((struct io_tw_req){link}, tw);
+		link = nxt;
+	}
+}
+
+static void io_fail_links(struct io_kiocb *req)
+	__must_hold(&req->ctx->completion_lock)
+{
+	struct io_kiocb *link = req->link;
+	bool ignore_cqes = req->flags & REQ_F_SKIP_LINK_CQES;
+
+	if (!link)
+		return;
+
+	while (link) {
+		if (ignore_cqes)
+			link->flags |= REQ_F_CQE_SKIP;
+		else
+			link->flags &= ~REQ_F_CQE_SKIP;
+		trace_io_uring_fail_link(req, link);
+		link = link->link;
+	}
+
+	link = req->link;
+	link->io_task_work.func = io_req_tw_fail_links;
+	io_req_task_work_add(link);
+	req->link = NULL;
+}
+
+static inline void io_remove_next_linked(struct io_kiocb *req)
+{
+	struct io_kiocb *nxt = req->link;
+
+	req->link = nxt->link;
+	nxt->link = NULL;
+}
+
+void io_disarm_next(struct io_kiocb *req)
+	__must_hold(&req->ctx->completion_lock)
+{
+	struct io_kiocb *link = NULL;
+
+	if (req->flags & REQ_F_ARM_LTIMEOUT) {
+		link = req->link;
+		req->flags &= ~REQ_F_ARM_LTIMEOUT;
+		if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
+			io_remove_next_linked(req);
+			io_req_queue_tw_complete(link, -ECANCELED);
+		}
+	} else if (req->flags & REQ_F_LINK_TIMEOUT) {
+		struct io_ring_ctx *ctx = req->ctx;
+
+		raw_spin_lock_irq(&ctx->timeout_lock);
+		if (req->link && req->link->opcode == IORING_OP_LINK_TIMEOUT)
+			link = __io_disarm_linked_timeout(req, req->link);
+
+		raw_spin_unlock_irq(&ctx->timeout_lock);
+		if (link)
+			io_req_queue_tw_complete(link, -ECANCELED);
+	}
+	if (unlikely((req->flags & REQ_F_FAIL) &&
+		     !(req->flags & REQ_F_HARDLINK)))
+		io_fail_links(req);
+}
+
+static struct io_kiocb *__io_disarm_linked_timeout(struct io_kiocb *req,
+						   struct io_kiocb *link)
+	__must_hold(&req->ctx->completion_lock)
+	__must_hold(&req->ctx->timeout_lock)
+{
+	struct io_timeout_data *io = link->async_data;
+	struct io_timeout *timeout = io_kiocb_to_cmd(link, struct io_timeout);
+
+	io_remove_next_linked(req);
+
+	/* If this is NULL, then timer already claimed it and will complete it */
+	if (!timeout->head)
+		return NULL;
+	timeout->head = NULL;
+	if (hrtimer_try_to_cancel(&io->timer) != -1) {
+		list_del(&timeout->list);
+		return link;
+	}
+
+	return NULL;
+}
+
+static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
+{
+	struct io_timeout_data *data = container_of(timer,
+						struct io_timeout_data, timer);
+	struct io_kiocb *req = data->req;
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_ring_ctx *ctx = req->ctx;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&ctx->timeout_lock, flags);
+	list_del_init(&timeout->list);
+	atomic_set(&ctx->cq_timeouts,
+		atomic_read(&ctx->cq_timeouts) + 1);
+	raw_spin_unlock_irqrestore(&ctx->timeout_lock, flags);
+
+	if (!(data->flags & IORING_TIMEOUT_ETIME_SUCCESS))
+		req_set_fail(req);
+
+	io_req_set_res(req, -ETIME, 0);
+	req->io_task_work.func = io_timeout_complete;
+	io_req_task_work_add(req);
+	return HRTIMER_NORESTART;
+}
+
+static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
+					   struct io_cancel_data *cd)
+	__must_hold(&ctx->timeout_lock)
+{
+	struct io_timeout *timeout;
+	struct io_timeout_data *io;
+	struct io_kiocb *req = NULL;
+
+	list_for_each_entry(timeout, &ctx->timeout_list, list) {
+		struct io_kiocb *tmp = cmd_to_io_kiocb(timeout);
+
+		if (io_cancel_req_match(tmp, cd)) {
+			req = tmp;
+			break;
+		}
+	}
+	if (!req)
+		return ERR_PTR(-ENOENT);
+
+	io = req->async_data;
+	if (hrtimer_try_to_cancel(&io->timer) == -1)
+		return ERR_PTR(-EALREADY);
+	timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	list_del_init(&timeout->list);
+	return req;
+}
+
+int io_timeout_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
+	__must_hold(&ctx->completion_lock)
+{
+	struct io_kiocb *req;
+
+	raw_spin_lock_irq(&ctx->timeout_lock);
+	req = io_timeout_extract(ctx, cd);
+	raw_spin_unlock_irq(&ctx->timeout_lock);
+
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+	io_req_task_queue_fail(req, -ECANCELED);
+	return 0;
+}
+
+static void io_req_task_link_timeout(struct io_tw_req tw_req, io_tw_token_t tw)
+{
+	struct io_kiocb *req = tw_req.req;
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_kiocb *prev = timeout->prev;
+	int ret;
+
+	if (prev) {
+		/*
+		 * splice the linked timeout out of prev's chain if the regular
+		 * completion path didn't already do it.
+		 */
+		if (prev->link == req)
+			prev->link = req->link;
+		req->link = NULL;
+
+		if (!tw.cancel) {
+			struct io_cancel_data cd = {
+				.ctx		= req->ctx,
+				.data		= prev->cqe.user_data,
+			};
+
+			ret = io_try_cancel(req->tctx, &cd, 0);
+		} else {
+			ret = -ECANCELED;
+		}
+		io_req_set_res(req, ret ?: -ETIME, 0);
+		io_req_task_complete(tw_req, tw);
+		io_put_req(prev);
+	} else {
+		io_req_set_res(req, -ETIME, 0);
+		io_req_task_complete(tw_req, tw);
+	}
+}
+
+static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
+{
+	struct io_timeout_data *data = container_of(timer,
+						struct io_timeout_data, timer);
+	struct io_kiocb *prev, *req = data->req;
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_ring_ctx *ctx = req->ctx;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&ctx->timeout_lock, flags);
+	prev = timeout->head;
+	timeout->head = NULL;
+
+	/*
+	 * We don't expect the list to be empty, that will only happen if we
+	 * race with the completion of the linked work. Splice of prev is
+	 * done in io_req_task_link_timeout(), if needed.
+	 */
+	if (prev) {
+		if (!req_ref_inc_not_zero(prev)) {
+			io_remove_next_linked(prev);
+			prev = NULL;
+		}
+	}
+	list_del(&timeout->list);
+	timeout->prev = prev;
+	raw_spin_unlock_irqrestore(&ctx->timeout_lock, flags);
+
+	req->io_task_work.func = io_req_task_link_timeout;
+	io_req_task_work_add(req);
+	return HRTIMER_NORESTART;
+}
+
+static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
+{
+	return io_flags_to_clock(data->flags);
+}
+
+static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
+				    ktime_t ts, enum hrtimer_mode mode)
+	__must_hold(&ctx->timeout_lock)
+{
+	struct io_timeout_data *io;
+	struct io_timeout *timeout;
+	struct io_kiocb *req = NULL;
+
+	list_for_each_entry(timeout, &ctx->ltimeout_list, list) {
+		struct io_kiocb *tmp = cmd_to_io_kiocb(timeout);
+
+		if (user_data == tmp->cqe.user_data) {
+			req = tmp;
+			break;
+		}
+	}
+	if (!req)
+		return -ENOENT;
+
+	io = req->async_data;
+	if (hrtimer_try_to_cancel(&io->timer) == -1)
+		return -EALREADY;
+	hrtimer_setup(&io->timer, io_link_timeout_fn, io_timeout_get_clock(io), mode);
+	hrtimer_start(&io->timer, ts, mode);
+	return 0;
+}
+
+static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
+			     ktime_t time, enum hrtimer_mode mode)
+	__must_hold(&ctx->timeout_lock)
+{
+	struct io_cancel_data cd = { .ctx = ctx, .data = user_data, };
+	struct io_kiocb *req = io_timeout_extract(ctx, &cd);
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_timeout_data *data;
+
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	timeout->off = 0; /* noseq */
+	data = req->async_data;
+	data->time = time;
+
+	list_add_tail(&timeout->list, &ctx->timeout_list);
+	hrtimer_setup(&data->timer, io_timeout_fn, io_timeout_get_clock(data), mode);
+	hrtimer_start(&data->timer, data->time, mode);
+	return 0;
+}
+
+int io_timeout_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	struct io_timeout_rem *tr = io_kiocb_to_cmd(req, struct io_timeout_rem);
+	int ret;
+
+	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+		return -EINVAL;
+	if (sqe->addr3 || sqe->__pad2[0])
+		return -EINVAL;
+	if (sqe->buf_index || sqe->len || sqe->splice_fd_in)
+		return -EINVAL;
+
+	tr->ltimeout = false;
+	tr->addr = READ_ONCE(sqe->addr);
+	tr->flags = READ_ONCE(sqe->timeout_flags);
+	if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
+		if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
+			return -EINVAL;
+		if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
+			tr->ltimeout = true;
+		if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK |
+				  IORING_TIMEOUT_ABS |
+				  IORING_TIMEOUT_IMMEDIATE_ARG))
+			return -EINVAL;
+		ret = io_parse_user_time(&tr->time, READ_ONCE(sqe->addr2), tr->flags);
+		if (ret)
+			return ret;
+	} else if (tr->flags) {
+		/* timeout removal doesn't support flags */
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
+{
+	return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
+					    : HRTIMER_MODE_REL;
+}
+
+/*
+ * Remove or update an existing timeout command
+ */
+int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_timeout_rem *tr = io_kiocb_to_cmd(req, struct io_timeout_rem);
+	struct io_ring_ctx *ctx = req->ctx;
+	int ret;
+
+	if (!(tr->flags & IORING_TIMEOUT_UPDATE)) {
+		struct io_cancel_data cd = { .ctx = ctx, .data = tr->addr, };
+
+		spin_lock(&ctx->completion_lock);
+		ret = io_timeout_cancel(ctx, &cd);
+		spin_unlock(&ctx->completion_lock);
+	} else {
+		enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
+
+		raw_spin_lock_irq(&ctx->timeout_lock);
+		if (tr->ltimeout)
+			ret = io_linked_timeout_update(ctx, tr->addr, tr->time, mode);
+		else
+			ret = io_timeout_update(ctx, tr->addr, tr->time, mode);
+		raw_spin_unlock_irq(&ctx->timeout_lock);
+	}
+
+	if (ret < 0)
+		req_set_fail(req);
+	io_req_set_res(req, ret, 0);
+	return IOU_COMPLETE;
+}
+
+static int __io_timeout_prep(struct io_kiocb *req,
+			     const struct io_uring_sqe *sqe,
+			     bool is_timeout_link)
+{
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_timeout_data *data;
+	unsigned flags;
+	u32 off = READ_ONCE(sqe->off);
+	int ret;
+
+	if (sqe->addr3 || sqe->__pad2[0])
+		return -EINVAL;
+	if (sqe->buf_index || sqe->len != 1 || sqe->splice_fd_in)
+		return -EINVAL;
+	if (off && is_timeout_link)
+		return -EINVAL;
+	flags = READ_ONCE(sqe->timeout_flags);
+	if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK |
+		      IORING_TIMEOUT_ETIME_SUCCESS |
+		      IORING_TIMEOUT_MULTISHOT |
+		      IORING_TIMEOUT_IMMEDIATE_ARG))
+		return -EINVAL;
+	/* more than one clock specified is invalid, obviously */
+	if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
+		return -EINVAL;
+	/* multishot requests only make sense with rel values */
+	if (!(~flags & (IORING_TIMEOUT_MULTISHOT | IORING_TIMEOUT_ABS)))
+		return -EINVAL;
+
+	INIT_LIST_HEAD(&timeout->list);
+	timeout->off = off;
+	if (unlikely(off && !(req->ctx->int_flags & IO_RING_F_OFF_TIMEOUT_USED)))
+		req->ctx->int_flags |= IO_RING_F_OFF_TIMEOUT_USED;
+	/*
+	 * for multishot reqs w/ fixed nr of repeats, repeats tracks the
+	 * remaining nr
+	 */
+	timeout->repeats = 0;
+	if ((flags & IORING_TIMEOUT_MULTISHOT) && off > 0)
+		timeout->repeats = off;
+
+	if (WARN_ON_ONCE(req_has_async_data(req)))
+		return -EFAULT;
+	data = io_uring_alloc_async_data(NULL, req);
+	if (!data)
+		return -ENOMEM;
+	data->req = req;
+	data->flags = flags;
+
+	ret = io_parse_user_time(&data->time, READ_ONCE(sqe->addr), flags);
+	if (ret)
+		return ret;
+
+	data->mode = io_translate_timeout_mode(flags);
+
+	if (is_timeout_link) {
+		struct io_submit_link *link = &req->ctx->submit_state.link;
+
+		if (!link->head)
+			return -EINVAL;
+		if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
+			return -EINVAL;
+		timeout->head = link->last;
+		link->last->flags |= REQ_F_ARM_LTIMEOUT;
+		hrtimer_setup(&data->timer, io_link_timeout_fn, io_timeout_get_clock(data),
+			      data->mode);
+	} else {
+		hrtimer_setup(&data->timer, io_timeout_fn, io_timeout_get_clock(data), data->mode);
+	}
+	return 0;
+}
+
+int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	return __io_timeout_prep(req, sqe, false);
+}
+
+int io_link_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	return __io_timeout_prep(req, sqe, true);
+}
+
+int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_ring_ctx *ctx = req->ctx;
+	struct io_timeout_data *data = req->async_data;
+	struct list_head *entry;
+	u32 tail, off = timeout->off;
+
+	raw_spin_lock_irq(&ctx->timeout_lock);
+
+	/*
+	 * sqe->off holds how many events that need to occur for this
+	 * timeout event to be satisfied. If it isn't set, then this is
+	 * a pure timeout request, sequence isn't used.
+	 */
+	if (io_is_timeout_noseq(req)) {
+		entry = ctx->timeout_list.prev;
+		goto add;
+	}
+
+	tail = data_race(ctx->cached_cq_tail) - atomic_read(&ctx->cq_timeouts);
+	timeout->target_seq = tail + off;
+
+	/* Update the last seq here in case io_flush_timeouts() hasn't.
+	 * This is safe because ->completion_lock is held, and submissions
+	 * and completions are never mixed in the same ->completion_lock section.
+	 */
+	ctx->cq_last_tm_flush = tail;
+
+	/*
+	 * Insertion sort, ensuring the first entry in the list is always
+	 * the one we need first.
+	 */
+	list_for_each_prev(entry, &ctx->timeout_list) {
+		struct io_timeout *nextt = list_entry(entry, struct io_timeout, list);
+		struct io_kiocb *nxt = cmd_to_io_kiocb(nextt);
+
+		if (io_is_timeout_noseq(nxt))
+			continue;
+		/* nxt.seq is behind @tail, otherwise would've been completed */
+		if (off >= nextt->target_seq - tail)
+			break;
+	}
+add:
+	list_add(&timeout->list, entry);
+	hrtimer_start(&data->timer, data->time, data->mode);
+	raw_spin_unlock_irq(&ctx->timeout_lock);
+	return IOU_ISSUE_SKIP_COMPLETE;
+}
+
+void io_queue_linked_timeout(struct io_kiocb *req)
+{
+	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
+	struct io_ring_ctx *ctx = req->ctx;
+
+	raw_spin_lock_irq(&ctx->timeout_lock);
+	/*
+	 * If the back reference is NULL, then our linked request finished
+	 * before we got a chance to setup the timer
+	 */
+	if (timeout->head) {
+		struct io_timeout_data *data = req->async_data;
+
+		hrtimer_start(&data->timer, data->time, data->mode);
+		list_add_tail(&timeout->list, &ctx->ltimeout_list);
+	}
+	raw_spin_unlock_irq(&ctx->timeout_lock);
+	/* drop submission reference */
+	io_put_req(req);
+}
+
+static bool io_match_task(struct io_kiocb *head, struct io_uring_task *tctx,
+			  bool cancel_all)
+	__must_hold(&head->ctx->timeout_lock)
+{
+	struct io_kiocb *req;
+
+	if (tctx && head->tctx != tctx)
+		return false;
+	if (cancel_all)
+		return true;
+
+	io_for_each_link(req, head) {
+		if (req->flags & REQ_F_INFLIGHT)
+			return true;
+	}
+	return false;
+}
+
+/* Returns true if we found and killed one or more timeouts */
+__cold bool io_kill_timeouts(struct io_ring_ctx *ctx, struct io_uring_task *tctx,
+			     bool cancel_all)
+{
+	struct io_timeout *timeout, *tmp;
+	LIST_HEAD(list);
+
+	/*
+	 * completion_lock is needed for io_match_task(). Take it before
+	 * timeout_lockfirst to keep locking ordering.
+	 */
+	spin_lock(&ctx->completion_lock);
+	raw_spin_lock_irq(&ctx->timeout_lock);
+	list_for_each_entry_safe(timeout, tmp, &ctx->timeout_list, list) {
+		struct io_kiocb *req = cmd_to_io_kiocb(timeout);
+
+		if (io_match_task(req, tctx, cancel_all))
+			io_kill_timeout(req, &list);
+	}
+	raw_spin_unlock_irq(&ctx->timeout_lock);
+	spin_unlock(&ctx->completion_lock);
+
+	return io_flush_killed_timeouts(&list, -ECANCELED);
+}