Mark async operations such as RENAME, REMOVE, COMMIT MOVEABLE
for the nfsv4.1+ sessions.

Fixes: 85e39feead948 ("NFSv4.1 identify and mark RPC tasks that can move between transports")
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

When we handle an error by redirtying the page, we're not corrupting the
mapping, so we don't want the error to be recorded in the mapping.
If the caller has specified a sync_mode of WB_SYNC_NONE, we can just
return AOP_WRITEPAGE_ACTIVATE. However if we're dealing with
WB_SYNC_ALL, we need to ensure that retries happen when the errors are
non-fatal.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Fixes: 8fc75bed96bb ("NFS: Fix up return value on fatal errors in nfs_page_async_flush()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Since errors from nfs_pageio_complete() are already being reported
through nfs_async_write_error(), we should not be returning them to the
callers of do_writepages() as well. They will end up being reported
through the generic mechanism instead.

Fixes: 6fbda89b257f ("NFS: Replace custom error reporting mechanism with generic one")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

If the attempt to flush data was interrupted due to a local signal, then
just requeue the writes back for I/O.

Fixes: 6fbda89b257f ("NFS: Replace custom error reporting mechanism with generic one")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

Pull NFS client updates from Trond Myklebust:
 "Highlights include:

  Features:

   - Switch NFS to use readahead instead of the obsolete readpages.

   - Readdir fixes to improve cacheability of large directories when
     there are multiple readers and writers.

   - Readdir performance improvements when doing a seekdir() immediately
     after opening the directory (common when re-exporting NFS).

   - NFS swap improvements from Neil Brown.

   - Loosen up memory allocation to permit direct reclaim and write back
     in cases where there is no danger of deadlocking the writeback code
     or NFS swap.

   - Avoid sillyrename when the NFSv4 server claims to support the
     necessary features to recover the unlinked but open file after
     reboot.

  Bugfixes:

   - Patch from Olga to add a mount option to control NFSv4.1 session
     trunking discovery, and default it to being off.

   - Fix a lockup in nfs_do_recoalesce().

   - Two fixes for list iterator variables being used when pointing to
     the list head.

   - Fix a kernel memory scribble when reading from a non-socket
     transport in /sys/kernel/sunrpc.

   - Fix a race where reconnecting to a server could leave the TCP
     socket stuck forever in the connecting state.

   - Patch from Neil to fix a shutdown race which can leave the SUNRPC
     transport timer primed after we free the struct xprt itself.

   - Patch from Xin Xiong to fix reference count leaks in the NFSv4.2
     copy offload.

   - Sunrpc patch from Olga to avoid resending a task on an offlined
     transport.

  Cleanups:

   - Patches from Dave Wysochanski to clean up the fscache code"

* tag 'nfs-for-5.18-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (91 commits)
  NFSv4/pNFS: Fix another issue with a list iterator pointing to the head
  NFS: Don't loop forever in nfs_do_recoalesce()
  SUNRPC: Don't return error values in sysfs read of closed files
  SUNRPC: Do not dereference non-socket transports in sysfs
  NFSv4.1: don't retry BIND_CONN_TO_SESSION on session error
  SUNRPC don't resend a task on an offlined transport
  NFS: replace usage of found with dedicated list iterator variable
  SUNRPC: avoid race between mod_timer() and del_timer_sync()
  pNFS/files: Ensure pNFS allocation modes are consistent with nfsiod
  pNFS/flexfiles: Ensure pNFS allocation modes are consistent with nfsiod
  NFSv4/pnfs: Ensure pNFS allocation modes are consistent with nfsiod
  NFS: Avoid writeback threads getting stuck in mempool_alloc()
  NFS: nfsiod should not block forever in mempool_alloc()
  SUNRPC: Make the rpciod and xprtiod slab allocation modes consistent
  SUNRPC: Fix unx_lookup_cred() allocation
  NFS: Fix memory allocation in rpc_alloc_task()
  NFS: Fix memory allocation in rpc_malloc()
  SUNRPC: Improve accuracy of socket ENOBUFS determination
  SUNRPC: Replace internal use of SOCKWQ_ASYNC_NOSPACE
  SUNRPC: Fix socket waits for write buffer space
  ...

Pull filesystem folio updates from Matthew Wilcox:
 "Primarily this series converts some of the address_space operations to
  take a folio instead of a page.

  Notably:

   - a_ops->is_partially_uptodate() takes a folio instead of a page and
     changes the type of the 'from' and 'count' arguments to make it
     obvious they're bytes.

   - a_ops->invalidatepage() becomes ->invalidate_folio() and has a
     similar type change.

   - a_ops->launder_page() becomes ->launder_folio()

   - a_ops->set_page_dirty() becomes ->dirty_folio() and adds the
     address_space as an argument.

  There are a couple of other misc changes up front that weren't worth
  separating into their own pull request"

* tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits)
  fs: Remove aops ->set_page_dirty
  fb_defio: Use noop_dirty_folio()
  fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio
  fs: Convert __set_page_dirty_buffers to block_dirty_folio
  nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio()
  mm: Convert swap_set_page_dirty() to swap_dirty_folio()
  ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio
  f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio
  f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio
  f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio
  afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio()
  btrfs: Convert extent_range_redirty_for_io() to use folios
  fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
  btrfs: Convert from set_page_dirty to dirty_folio
  fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
  fs: Add aops->dirty_folio
  fs: Remove aops->launder_page
  orangefs: Convert launder_page to launder_folio
  nfs: Convert from launder_page to launder_folio
  fuse: Convert from launder_page to launder_folio
  ...

The bdi congestion tracking in not widely used and will be removed.

NFS is one of a small number of filesystems that uses it, setting just
the async (write) congestion flag at what it determines are appropriate
times.

The only remaining effect of the async flag is to cause (some)
WB_SYNC_NONE writes to be skipped.

So instead of setting the flag, set an internal flag and change:

 - .writepages to do nothing if WB_SYNC_NONE and the flag is set

 - .writepage to return AOP_WRITEPAGE_ACTIVATE if WB_SYNC_NONE and the
   flag is set.

The writepages change causes a behavioural change in that pageout() can
now return PAGE_ACTIVATE instead of PAGE_KEEP, so SetPageActive() will be
called on the page which (I think) wil further delay the next attempt at
writeout.  This might be a good thing.

Link: https://lkml.kernel.org/r/164549983738.9187.3972219847989393182.stgit@noble.brown
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In a low memory situation, allow the NFS writeback code to fail without
getting stuck in infinite loops in mempool_alloc().

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

The concern is that since nfsiod is sometimes required to kick off a
commit, it can get locked up waiting forever in mempool_alloc() instead
of failing gracefully and leaving the commit until later.

Try to allocate from the slab first, with GFP_KERNEL | __GFP_NORETRY,
then fall back to a non-blocking attempt to allocate from the memory
pool.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Print the folio index instead of the pointer, since this is more
useful.  We also don't need to use page_file_mapping() as we do not
invalidate swapcache pages.  Since this is the only caller of
nfs_wb_page_cancel(), convert it to nfs_wb_folio_cancel().

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs