Pull cifs fixes from Steve French:
 "Three small fixes: a fix for smb3 direct i/o, a fix for CIFS DFS for
  stable and a minor cifs Kconfig fix"

* tag '4.20-rc5-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Avoid returning EBUSY to upper layer VFS
  cifs: Fix separator when building path from dentry
  cifs: In Kconfig CONFIG_CIFS_POSIX needs depends on legacy (insecure cifs)

Pull dax fixes from Dan Williams:
 "The last of the known regression fixes and fallout from the Xarray
  conversion of the filesystem-dax implementation.

  On the path to debugging why the dax memory-failure injection test
  started failing after the Xarray conversion a couple more fixes for
  the dax_lock_mapping_entry(), now called dax_lock_page(), surfaced.
  Those plus the bug that started the hunt are now addressed. These
  patches have appeared in a -next release with no issues reported.

  Note the touches to mm/memory-failure.c are just the conversion to the
  new function signature for dax_lock_page().

  Summary:

   - Fix the Xarray conversion of fsdax to properly handle
     dax_lock_mapping_entry() in the presense of pmd entries

   - Fix inode destruction racing a new lock request"

* tag 'dax-fixes-4.20-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  dax: Fix unlock mismatch with updated API
  dax: Don't access a freed inode
  dax: Check page->mapping isn't NULL

Pull xfs fixes from Darrick Wong:
 "Here are hopefully the last set of fixes for 4.20.

  There's a fix for a longstanding statfs reporting problem with project
  quotas, a correction for page cache invalidation behaviors when
  fallocating near EOF, and a fix for a broken metadata verifier return
  code.

  Finally, the most important fix is to the pipe splicing code (aka the
  generic copy_file_range fallback) to avoid pointless short directio
  reads by only asking the filesystem for as much data as there are
  available pages in the pipe buffer. Our previous fix (simulated short
  directio reads because the number of pages didn't match the length of
  the read requested) caused subtle problems on overlayfs, so that part
  is reverted.

  Anyhow, this series passes fstests -g all on xfs and overlay+xfs, and
  has passed 17 billion fsx operations problem-free since I started
  testing

  Summary:

   - Fix broken project quota inode counts

   - Fix incorrect PAGE_MASK/PAGE_SIZE usage

   - Fix incorrect return value in btree verifier

   - Fix WARN_ON remap flags false positive

   - Fix splice read overflows"

* tag 'xfs-4.20-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: partially revert 4721a601099 (simulated directio short read on EFAULT)
  splice: don't read more than available pipe space
  vfs: allow some remap flags to be passed to vfs_clone_file_range
  xfs: fix inverted return from xfs_btree_sblock_verify_crc
  xfs: fix PAGE_MASK usage in xfs_free_file_space
  fs/xfs: fix f_ffree value for statfs when project quota is set

EBUSY is not handled by VFS, and will be passed to user-mode. This is not
correct as we need to wait for more credits.

This patch also fixes a bug where rsize or wsize is used uninitialized when
the call to server->ops->wait_mtu_credits() fails.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

Pull NFS client bugfixes from Trond Myklebust:
 "This is mainly fallout from the updates to the SUNRPC code that is
  being triggered from less common combinations of NFS mount options.

  Highlights include:

  Stable fixes:
   - Fix a page leak when using RPCSEC_GSS/krb5p to encrypt data.

  Bugfixes:
   - Fix a regression that causes the RPC receive code to hang
   - Fix call_connect_status() so that it handles tasks that got
     transmitted while queued waiting for the socket lock.
   - Fix a memory leak in call_encode()
   - Fix several other connect races.
   - Fix receive code error handling.
   - Use the discard iterator rather than MSG_TRUNC for compatibility
     with AF_UNIX/AF_LOCAL sockets.
   - nfs: don't dirty kernel pages read by direct-io
   - pnfs/Flexfiles fix to enforce per-mirror stateid only for NFSv4
     data servers"

* tag 'nfs-for-4.20-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Don't force a redundant disconnection in xs_read_stream()
  SUNRPC: Fix up socket polling
  SUNRPC: Use the discard iterator rather than MSG_TRUNC
  SUNRPC: Treat EFAULT as a truncated message in xs_read_stream_request()
  SUNRPC: Fix up handling of the XDRBUF_SPARSE_PAGES flag
  SUNRPC: Fix RPC receive hangs
  SUNRPC: Fix a potential race in xprt_connect()
  SUNRPC: Fix a memory leak in call_encode()
  SUNRPC: Fix leak of krb5p encode pages
  SUNRPC: call_connect_status() must handle tasks that got transmitted
  nfs: don't dirty kernel pages read by direct-io
  flexfiles: enforce per-mirror stateid only for v4 DSes

Make sure to use the CIFS_DIR_SEP(cifs_sb) as path separator for
prefixpath too. Fixes a bug with smb1 UNIX extensions.

Fixes: a6b5058fafdf ("fs/cifs: make share unaccessible at root level mountable")
Signed-off-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>

Missing a dependency.  Shouldn't show cifs posix extensions
in Kconfig if CONFIG_CIFS_ALLOW_INSECURE_DIALECTS (ie SMB1
protocol) is disabled.

Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

Pull btrfs fix from David Sterba:
 "A patch in 4.19 introduced a sanity check that was too strict and a
  filesystem cannot be mounted.

  This happens for filesystems with more than 10 devices and has been
  reported by a few users so we need the fix to propagate to stable"

* tag 'for-4.20-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: tree-checker: Don't check max block group size as current max chunk size limit is unreliable

Internal to dax_unlock_mapping_entry(), dax_unlock_entry() is used to
store a replacement entry in the Xarray at the given xas-index with the
DAX_LOCKED bit clear. When called, dax_unlock_entry() expects the unlocked
value of the entry relative to the current Xarray state to be specified.

In most contexts dax_unlock_entry() is operating in the same scope as
the matched dax_lock_entry(). However, in the dax_unlock_mapping_entry()
case the implementation needs to recall the original entry. In the case
where the original entry is a 'pmd' entry it is possible that the pfn
performed to do the lookup is misaligned to the value retrieved in the
Xarray.

Change the api to return the unlock cookie from dax_lock_page() and pass
it to dax_unlock_page(). This fixes a bug where dax_unlock_page() was
assuming that the page was PMD-aligned if the entry was a PMD entry with
signatures like:

 WARNING: CPU: 38 PID: 1396 at fs/dax.c:340 dax_insert_entry+0x2b2/0x2d0
 RIP: 0010:dax_insert_entry+0x2b2/0x2d0
 [..]
 Call Trace:
  dax_iomap_pte_fault.isra.41+0x791/0xde0
  ext4_dax_huge_fault+0x16f/0x1f0
  ? up_read+0x1c/0xa0
  __do_fault+0x1f/0x160
  __handle_mm_fault+0x1033/0x1490
  handle_mm_fault+0x18b/0x3d0

Link: https://lkml.kernel.org/r/20181130154902.GL10377@bombadil.infradead.org
Fixes: 9f32d221301c ("dax: Convert dax_lock_mapping_entry to XArray")
Reported-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Matthew Wilcox <willy@infradead.org>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

In commit 4721a601099, we tried to fix a problem wherein directio reads
into a splice pipe will bounce EFAULT/EAGAIN all the way out to
userspace by simulating a zero-byte short read.  This happens because
some directio read implementations (xfs) will call
bio_iov_iter_get_pages to grab pipe buffer pages and issue asynchronous
reads, but as soon as we run out of pipe buffers that _get_pages call
returns EFAULT, which the splice code translates to EAGAIN and bounces
out to userspace.

In that commit, the iomap code catches the EFAULT and simulates a
zero-byte read, but that causes assertion errors on regular splice reads
because xfs doesn't allow short directio reads.  This causes infinite
splice() loops and assertion failures on generic/095 on overlayfs
because xfs only permit total success or total failure of a directio
operation.  The underlying issue in the pipe splice code has now been
fixed by changing the pipe splice loop to avoid avoid reading more data
than there is space in the pipe.

Therefore, it's no longer necessary to simulate the short directio, so
remove the hack from iomap.

Fixes: 4721a601099 ("iomap: dio data corruption and spurious errors when pipes fill")
Reported-by: Murphy Zhou <jencce.kernel@gmail.com>
Ranted-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>