Patch series "remove Xen tmem leftovers".

Since the removal of the Xen tmem driver in 2019, the cleancache hooks
are entirely unused, as are large parts of frontswap.  This series
against linux-next (with the folio changes included) removes
cleancaches, and cuts down frontswap to the bits actually used by zswap.

This patch (of 13):

The cleancache subsystem is unused since the removal of Xen tmem driver
in commit 814bbf49dcd0 ("xen: remove tmem driver").

[akpm@linux-foundation.org: remove now-unreachable code]

Link: https://lkml.kernel.org/r/20211224062246.1258487-1-hch@lst.de
Link: https://lkml.kernel.org/r/20211224062246.1258487-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Konrad Rzeszutek Wilk <Konrad.wilk@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull gfs2 mmap + page fault deadlocks fixes from Andreas Gruenbacher:
 "Functions gfs2_file_read_iter and gfs2_file_write_iter are both
  accessing the user buffer to write to or read from while holding the
  inode glock.

  In the most basic deadlock scenario, that buffer will not be resident
  and it will be mapped to the same file. Accessing the buffer will
  trigger a page fault, and gfs2 will deadlock trying to take the same
  inode glock again while trying to handle that fault.

  Fix that and similar, more complex scenarios by disabling page faults
  while accessing user buffers. To make this work, introduce a small
  amount of new infrastructure and fix some bugs that didn't trigger so
  far, with page faults enabled"

* tag 'gfs2-v5.15-rc5-mmap-fault' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix mmap + page fault deadlocks for direct I/O
  iov_iter: Introduce nofault flag to disable page faults
  gup: Introduce FOLL_NOFAULT flag to disable page faults
  iomap: Add done_before argument to iomap_dio_rw
  iomap: Support partial direct I/O on user copy failures
  iomap: Fix iomap_dio_rw return value for user copies
  gfs2: Fix mmap + page fault deadlocks for buffered I/O
  gfs2: Eliminate ip->i_gh
  gfs2: Move the inode glock locking to gfs2_file_buffered_write
  gfs2: Introduce flag for glock holder auto-demotion
  gfs2: Clean up function may_grant
  gfs2: Add wrapper for iomap_file_buffered_write
  iov_iter: Introduce fault_in_iov_iter_writeable
  iov_iter: Turn iov_iter_fault_in_readable into fault_in_iov_iter_readable
  gup: Turn fault_in_pages_{readable,writeable} into fault_in_{readable,writeable}
  powerpc/kvm: Fix kvm_use_magic_page
  iov_iter: Fix iov_iter_get_pages{,_alloc} page fault return value

Pull block inode sync updates from Jens Axboe:
 "This contains improvements to how bdev inode syncing is handled,
  unifying the API"

* tag 'for-5.16/inode-sync-2021-10-29' of git://git.kernel.dk/linux-block:
  block: simplify the block device syncing code
  ntfs3: use sync_blockdev_nowait
  fat: use sync_blockdev_nowait
  btrfs: use sync_blockdev
  xen-blkback: use sync_blockdev
  block: remove __sync_blockdev
  fs: remove __sync_filesystem

Use sync_blockdev_nowait instead of opencoding it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20211019062530.2174626-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Use the proper helper to read the block device size.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211018101130.1838532-21-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Turn iov_iter_fault_in_readable into a function that returns the number
of bytes not faulted in, similar to copy_to_user, instead of returning a
non-zero value when any of the requested pages couldn't be faulted in.
This supports the existing users that require all pages to be faulted in
as well as new users that are happy if any pages can be faulted in.

Rename iov_iter_fault_in_readable to fault_in_iov_iter_readable to make
sure this change doesn't silently break things.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Move inode_to_bdi out of line to avoid having to include blkdev.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull ntfs3 fixes from Konstantin Komarov:
 "Use the new api for mounting as requested by Christoph.

  Also fixed:

   - some memory leaks and panic

   - xfstests (tested on x86_64) generic/016 generic/021 generic/022
     generic/041 generic/274 generic/423

   - some typos, wrong returned error codes, dead code, etc"

* tag 'ntfs3_for_5.15' of git://github.com/Paragon-Software-Group/linux-ntfs3: (70 commits)
  fs/ntfs3: Check for NULL pointers in ni_try_remove_attr_list
  fs/ntfs3: Refactor ntfs_read_mft
  fs/ntfs3: Refactor ni_parse_reparse
  fs/ntfs3: Refactor ntfs_create_inode
  fs/ntfs3: Refactor ntfs_readlink_hlp
  fs/ntfs3: Rework ntfs_utf16_to_nls
  fs/ntfs3: Fix memory leak if fill_super failed
  fs/ntfs3: Keep prealloc for all types of files
  fs/ntfs3: Remove unnecessary functions
  fs/ntfs3: Forbid FALLOC_FL_PUNCH_HOLE for normal files
  fs/ntfs3: Refactoring of ntfs_set_ea
  fs/ntfs3: Remove locked argument in ntfs_set_ea
  fs/ntfs3: Use available posix_acl_release instead of ntfs_posix_acl_release
  fs/ntfs3: Check for NULL if ATTR_EA_INFO is incorrect
  fs/ntfs3: Refactoring of ntfs_init_from_boot
  fs/ntfs3: Reject mount if boot's cluster size < media sector size
  fs/ntfs3: Refactoring lock in ntfs_init_acl
  fs/ntfs3: Change posix_acl_equiv_mode to posix_acl_update_mode
  fs/ntfs3: Pass flags to ntfs_set_ea in ntfs_set_acl_ex
  fs/ntfs3: Refactor ntfs_get_acl_ex for better readability
  ...

Check for potential NULL pointers.
Print error message if found.
Thread, that leads to this commit:
https://lore.kernel.org/ntfs3/227c13e3-5a22-0cba-41eb-fcaf41940711@paragon-software.com/

Reported-by: Mohammad Rasim <mohammad.rasim96@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

Don't save size of attribute reparse point as size of symlink.

Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>