Merge tag 'for-6.12/io_uring-discard-20240913' of git://git.kernel.dk/linux

Merge tag 'for-6.12/io_uring-discard-20240913' of git://git.kernel.dk/linux

Pull io_uring async discard support from Jens Axboe:
 "Sitting on top of both the 6.12 block and io_uring core branches,
  here's support for async discard through io_uring.

  This allows applications to issue async discards, rather than rely on
  the blocking sync ioctl discards we already have. The sync support is
  difficult to use outside of idle/cleanup periods.

  On a real (but slow) device, testing shows the following results when
  compared to sync discard:

	qd64 sync discard: 21K IOPS, lat avg 3 msec (max 21 msec)
	qd64 async discard: 76K IOPS, lat avg 845 usec (max 2.2 msec)

	qd64 sync discard: 14K IOPS, lat avg 5 msec (max 25 msec)
	qd64 async discard: 56K IOPS, lat avg 1153 usec (max 3.6 msec)

  and synthetic null_blk testing with the same queue depth and block
  size settings as above shows:

	Type    Trim size       IOPS    Lat avg (usec)  Lat Max (usec)
	==============================================================
	sync    4k               144K       444            20314
	async   4k              1353K        47              595
	sync    1M                56K      1136            21031
	async   1M                94K       680              760"

* tag 'for-6.12/io_uring-discard-20240913' of git://git.kernel.dk/linux:
  block: implement async io_uring discard cmd
  block: introduce blk_validate_byte_range()
  filemap: introduce filemap_invalidate_pages
  io_uring/cmd: give inline space in request to cmds
  io_uring/cmd: expose iowq to cmds