[GIT PULL] Turn single vector imports into ITER_UBUF

[Jens Axboe <axboe@kernel.dk>]

Hi Linus,

This series turns singe vector imports into ITER_UBUF, rather than
ITER_IOVEC. The former is more trivial to iterate and advance, and hence
a bit more efficient. From some very unscientific testing, ~60% of all
iovec imports are single vector.

One fixup patch from Josh since this was last posted, fixing a UACCESS
complaint that was due to the compiler optimization gone wrong where it
moves user_access_begin() outside of copy_compat_iovec_from_user().

This has been in linux-next for about a month without any complaints,
outside of the above mentioned UACCESS warning.

Please pull for 6.4-rc1!


The following changes since commit 3a93e40326c8f470e71d20b4c42d36767450f38f:

  Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm (2023-03-27 12:22:45 -0700)

are available in the Git repository at:

  git://git.kernel.dk/linux.git tags/iter-ubuf.2-2023-04-21

for you to fetch changes up to 50f9a76ef127367847cf62999c79304e48018cfa:

  iov_iter: Mark copy_compat_iovec_from_user() noinline (2023-04-12 10:46:48 -0600)

----------------------------------------------------------------
iter-ubuf.2-2023-04-21

----------------------------------------------------------------
Jens Axboe (11):
      block: ensure bio_alloc_map_data() deals with ITER_UBUF correctly
      iov_iter: add iter_iovec() helper
      IB/hfi1: check for user backed iterator, not specific iterator type
      IB/qib: check for user backed iterator, not specific iterator type
      ALSA: pcm: check for user backed iterator, not specific iterator type
      iov_iter: add iter_iov_addr() and iter_iov_len() helpers
      iov_iter: remove iov_iter_iovec()
      iov_iter: set nr_segs = 1 for ITER_UBUF
      iov_iter: overlay struct iovec and ubuf/len
      iov_iter: convert import_single_range() to ITER_UBUF
      iov_iter: import single vector iovecs as ITER_UBUF

Josh Poimboeuf (1):
      iov_iter: Mark copy_compat_iovec_from_user() noinline

 block/blk-map.c                          |  7 +--
 drivers/infiniband/hw/hfi1/file_ops.c    | 10 ++--
 drivers/infiniband/hw/qib/qib_file_ops.c |  4 +-
 drivers/net/tun.c                        |  3 +-
 drivers/vhost/scsi.c                     |  2 +-
 fs/btrfs/file.c                          | 11 ++--
 fs/fuse/file.c                           |  2 +-
 fs/read_write.c                          | 11 ++--
 include/linux/uio.h                      | 57 ++++++++++++++------
 io_uring/net.c                           |  4 +-
 io_uring/rw.c                            | 35 ++++++-------
 lib/iov_iter.c                           | 89 +++++++++++++++++++++-----------
 mm/madvise.c                             |  9 ++--
 sound/core/pcm_native.c                  | 26 ++++++----
 14 files changed, 165 insertions(+), 105 deletions(-)

-- 
Jens Axboe