[GIT PULL for v6.7] vfs io updates

[Christian Brauner]

Hey Linus,

/* Summary */
This contain's David's iov_iter cleanup work to convert the iov_iter
iteration macros to inline functions:

* Remove last_offset from iov_iter as it was only used by ITER_PIPE.
* Add a __user tag on copy_mc_to_user()'s dst argument on x86 to match
  that on powerpc and get rid of a sparse warning.
* Convert iter->user_backed to user_backed_iter() in the sound PCM
  driver.
* Convert iter->user_backed to user_backed_iter() in a couple of
  infiniband drivers.
* Renumber the type enum so that the ITER_* constants match the order in
  iterate_and_advance*().
* Since the preceding patch puts UBUF and IOVEC at 0 and 1, change
  user_backed_iter() to just use the type value and get rid of the extra
  flag.
* Convert the iov_iter iteration macros to always-inline functions to
  make the code easier to follow. It uses function pointers, but they
  get optimised away.
* Move the check for ->copy_mc to _copy_from_iter() and
  copy_page_from_iter_atomic() rather than in memcpy_from_iter_mc()
  where it gets repeated for every segment.  Instead, we check once and
  invoke a side function that can use iterate_bvec() rather than
  iterate_and_advance() and supply a different step function.
* Move the copy-and-csum code to net/ where it can be in proximity with
  the code that uses it.
* Fold memcpy_and_csum() in to its two users.
* Move csum_and_copy_from_iter_full() out of line and merge in
  csum_and_copy_from_iter() since the former is the only caller of the
  latter.
* Move hash_and_copy_to_iter() to net/ where it can be with its only
  caller.

/* Testing */
clang: Debian clang version 16.0.6 (16)
gcc: gcc (Debian 13.2.0-5) 13.2.0

All patches are based on v6.6-rc2 and have been sitting in linux-next.
No build failures or warnings were observed.

/* Conflicts */
At the time of creating this PR no merge conflicts were reported from
linux-next and no merge conflicts showed up doing a test-merge with
current mainline.

The following changes since commit ce9ecca0238b140b88f43859b211c9fdfd8e5b70:

  Linux 6.6-rc2 (2023-09-17 14:40:24 -0700)

are available in the Git repository at:

  git@xxxxxxxxxxxxxxxxxxx:pub/scm/linux/kernel/git/vfs/vfs tags/vfs-6.7.iov_iter

for you to fetch changes up to b5f0e20f444cd150121e0ce912ebd3f2dabd12bc:

  iov_iter, net: Move hash_and_copy_to_iter() to net/ (2023-10-09 09:35:14 +0200)

Please consider pulling these changes from the signed vfs-6.7.iov_iter tag.

Thanks!
Christian

----------------------------------------------------------------
vfs-6.7.iov_iter

----------------------------------------------------------------
David Howells (12):
      iov_iter: Remove last_offset from iov_iter as it was for ITER_PIPE
      iov_iter, x86: Be consistent about the __user tag on copy_mc_to_user()
      sound: Fix snd_pcm_readv()/writev() to use iov access functions
      infiniband: Use user_backed_iter() to see if iterator is UBUF/IOVEC
      iov_iter: Renumber ITER_* constants
      iov_iter: Derive user-backedness from the iterator type
      iov_iter: Convert iterate*() to inline funcs
      iov_iter: Don't deal with iter->copy_mc in memcpy_from_iter_mc()
      iov_iter, net: Move csum_and_copy_to/from_iter() to net/
      iov_iter, net: Fold in csum_and_memcpy()
      iov_iter, net: Merge csum_and_copy_from_iter{,_full}() together
      iov_iter, net: Move hash_and_copy_to_iter() to net/

 arch/x86/include/asm/uaccess.h           |   2 +-
 arch/x86/lib/copy_mc.c                   |   8 +-
 drivers/infiniband/hw/hfi1/file_ops.c    |   2 +-
 drivers/infiniband/hw/qib/qib_file_ops.c |   2 +-
 include/linux/iov_iter.h                 | 274 +++++++++++++++++++
 include/linux/skbuff.h                   |   3 +
 include/linux/uio.h                      |  34 +--
 lib/iov_iter.c                           | 437 ++++++++++---------------------
 net/core/datagram.c                      |  75 +++++-
 net/core/skbuff.c                        |  40 +++
 sound/core/pcm_native.c                  |   4 +-
 11 files changed, 540 insertions(+), 341 deletions(-)
 create mode 100644 include/linux/iov_iter.h