Merge branch 'for-5.12/io_uring' into io_uring-worker.v3

* for-5.12/io_uring: (21 commits)
  io_uring: run task_work on io_uring_register()
  io_uring: fix leaving invalid req->flags
  io_uring: wait potential ->release() on resurrect
  io_uring: keep generic rsrc infra generic
  io_uring: zero ref_node after killing it
  io_uring: make the !CONFIG_NET helpers a bit more robust
  io_uring: don't hold uring_lock when calling io_run_task_work*
  io_uring: fail io-wq submission from a task_work
  io_uring: don't take uring_lock during iowq cancel
  io_uring: fail links more in io_submit_sqe()
  io_uring: don't do async setup for links' heads
  io_uring: do io_*_prep() early in io_submit_sqe()
  io_uring: split sqe-prep and async setup
  io_uring: don't submit link on error
  io_uring: move req link into submit_state
  io_uring: move io_init_req() into io_submit_sqe()
  io_uring: move io_init_req()'s definition
  io_uring: don't duplicate ->file check in sfr
  io_uring: keep io_*_prep() naming consistent
  io_uring: kill fictitious submit iteration index
  ...