[PATCH v10 0/5] io_uring: add xattr support

[Stefan Roesch <shr@fb.com>]

This adds the xattr support to io_uring. The intent is to have a more
complete support for file operations in io_uring.

This change adds support for the following functions to io_uring:
- fgetxattr
- fsetxattr
- getxattr
- setxattr

Patch 1: fs: split off do_user_path_at_empty from user_path_at_empty()
  This splits off a new function do_user_path_at_empty from
  user_path_at_empty that is based on filename and not on a
  user-specified string.

Patch 2: fs: split off setxattr_copy and do_setxattr function from setxattr
  Split off the setup part of the setxattr function in the setxattr_copy
  function. Split off the processing part in do_setxattr.

Patch 3: fs: split off do_getxattr from getxattr
  Split of the do_getxattr part from getxattr. This will
  allow it to be invoked it from io_uring.

Patch 4: io_uring: add fsetxattr and setxattr support
  This adds new functions to support the fsetxattr and setxattr
  functions.

Patch 5: io_uring: add fgetxattr and getxattr support
  This adds new functions to support the fgetxattr and getxattr
  functions.


There are two additional patches:
  liburing: Add support for xattr api's.
            This also includes the tests for the new code.
  xfstests: Add support for io_uring xattr support.


V10: - move do_user_path_at_empty definition to fs/internal.h
     - introduce __io_setxattr_finish function
     - introduce __io_getxattr_finish function
V9 : - keep kvalue in struct xattr_ctx
V8 : - introduce xattr_name struct as advised by Linus
     - remove kname_sz field in xattr_ctx
V7 : - split off setxattr in two functions as recommeneded by
       Christian.
V6 : - reverted addition of kname array to xattr_ctx structure
       Adding the kname array increases the io_kiocb beyond 64 bytes
       (increases it to 224 bytes). We try hard to limit it to 64 bytes.
       Keeping the original interface also is a bit more efficient.
     - addressed Pavel's reordering comment
     - addressed Pavel's putname comment
     - addressed Pavel's kvfree comment
     - rebased on for-5.17/io_uring-getdents64
V5 : - add kname array to xattr_ctx structure
V4 : - rebased patch series
V3 : - remove req->file checks in prep functions
     - change size parameter in do_xattr
V2 : - split off function do_user_path_empty instead of changing
       the function signature of user_path_at
     - Fix datatype size problem in do_getxattr


Stefan Roesch (5):
  fs: split off do_user_path_at_empty from user_path_at_empty()
  fs: split off setxattr_copy and do_setxattr function from setxattr
  fs: split off do_getxattr from getxattr
  io_uring: add fsetxattr and setxattr support
  io_uring: add fgetxattr and getxattr support

 fs/internal.h                 |  34 ++++
 fs/io_uring.c                 | 316 ++++++++++++++++++++++++++++++++++
 fs/namei.c                    |  10 +-
 fs/xattr.c                    | 114 ++++++++----
 include/uapi/linux/io_uring.h |   8 +-
 5 files changed, 444 insertions(+), 38 deletions(-)


base-commit: b4518682080d3a1cdd6ea45a54ff6772b8b2797a
-- 
2.30.2