make alloc_anon_inode more useful

[Christoph Hellwig]

Hi all,

this series first renames the existing alloc_anon_inode to
alloc_anon_inode_sb to clearly mark it as requiring a superblock.

It then adds a new alloc_anon_inode that works on the anon_inode
file system super block, thus removing tons of boilerplate code.

The few remainig callers of alloc_anon_inode_sb all use alloc_file_pseudo
later, but might also be ripe for some cleanup.

Diffstat:
 arch/powerpc/platforms/pseries/cmm.c |   27 +-------------
 drivers/dma-buf/dma-buf.c            |    2 -
 drivers/gpu/drm/drm_drv.c            |   64 +----------------------------------
 drivers/misc/cxl/api.c               |    2 -
 drivers/misc/vmw_balloon.c           |   24 +------------
 drivers/scsi/cxlflash/ocxl_hw.c      |    2 -
 drivers/virtio/virtio_balloon.c      |   30 +---------------
 fs/aio.c                             |    2 -
 fs/anon_inodes.c                     |   15 +++++++-
 fs/libfs.c                           |    2 -
 include/linux/anon_inodes.h          |    1 
 include/linux/fs.h                   |    2 -
 kernel/resource.c                    |   30 ++--------------
 mm/z3fold.c                          |   38 +-------------------
 mm/zsmalloc.c                        |   48 +-------------------------
 15 files changed, 39 insertions(+), 250 deletions(-)