Pull fuse update from Miklos Szeredi:
 "Various bug fixes and cleanups"

* tag 'fuse-update-4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: reduce allocation size for splice_write
  fuse: use kvmalloc to allocate array of pipe_buffer structs.
  fuse: convert last timespec use to timespec64
  fs: fuse: Adding new return type vm_fault_t
  fuse: simplify fuse_abort_conn()
  fuse: Add missed unlock_page() to fuse_readpages_fill()
  fuse: Don't access pipe->buffers without pipe_lock()
  fuse: fix initial parallel dirops
  fuse: Fix oops at process_init_reply()
  fuse: umount should wait for all requests
  fuse: fix unlocked access to processing queue
  fuse: fix double request_end()

Pull core signal handling updates from Eric Biederman:
 "It was observed that a periodic timer in combination with a
  sufficiently expensive fork could prevent fork from every completing.
  This contains the changes to remove the need for that restart.

  This set of changes is split into several parts:

   - The first part makes PIDTYPE_TGID a proper pid type instead
     something only for very special cases. The part starts using
     PIDTYPE_TGID enough so that in __send_signal where signals are
     actually delivered we know if the signal is being sent to a a group
     of processes or just a single process.

   - With that prep work out of the way the logic in fork is modified so
     that fork logically makes signals received while it is running
     appear to be received after the fork completes"

* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (22 commits)
  signal: Don't send signals to tasks that don't exist
  signal: Don't restart fork when signals come in.
  fork: Have new threads join on-going signal group stops
  fork: Skip setting TIF_SIGPENDING in ptrace_init_task
  signal: Add calculate_sigpending()
  fork: Unconditionally exit if a fatal signal is pending
  fork: Move and describe why the code examines PIDNS_ADDING
  signal: Push pid type down into complete_signal.
  signal: Push pid type down into __send_signal
  signal: Push pid type down into send_signal
  signal: Pass pid type into do_send_sig_info
  signal: Pass pid type into send_sigio_to_task & send_sigurg_to_task
  signal: Pass pid type into group_send_sig_info
  signal: Pass pid and pid type into send_sigqueue
  posix-timers: Noralize good_sigevent
  signal: Use PIDTYPE_TGID to clearly store where file signals will be sent
  pid: Implement PIDTYPE_TGID
  pids: Move the pgrp and session pid pointers from task_struct to signal_struct
  kvm: Don't open code task_pid in kvm_vcpu_ioctl
  pids: Compute task_tgid using signal->leader_pid
  ...

Pull vfs icache updates from Al Viro:

 - NFS mkdir/open_by_handle race fix

 - analogous solution for FUSE, replacing the one currently in mainline

 - new primitive to be used when discarding halfway set up inodes on
   failed object creation; gives sane warranties re icache lookups not
   returning such doomed by still not freed inodes. A bunch of
   filesystems switched to that animal.

 - Miklos' fix for last cycle regression in iget5_locked(); -stable will
   need a slightly different variant, unfortunately.

 - misc bits and pieces around things icache-related (in adfs and jfs).

* 'work.mkdir' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  jfs: don't bother with make_bad_inode() in ialloc()
  adfs: don't put inodes into icache
  new helper: inode_fake_hash()
  vfs: don't evict uninitialized inode
  jfs: switch to discard_new_inode()
  ext2: make sure that partially set up inodes won't be returned by ext2_iget()
  udf: switch to discard_new_inode()
  ufs: switch to discard_new_inode()
  btrfs: switch to discard_new_inode()
  new primitive: discard_new_inode()
  kill d_instantiate_no_diralias()
  nfs_instantiate(): prevent multiple aliases for directory inode

The only user is fuse_create_new_entry(), and there it's used to
mitigate the same mkdir/open-by-handle race as in nfs_mkdir().
The same solution applies - unhash the mkdir argument, then
call d_splice_alias() and if that returns a reference to preexisting
alias, dput() and report success.  ->mkdir() argument left unhashed
negative with the preexisting alias moved in the right place is just
fine from the ->mkdir() callers point of view.

Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

The 'bufs' array contains 'pipe->buffers' elements, but the
fuse_dev_splice_write() uses only 'pipe->nrbufs' elements.

So reduce the allocation size to 'pipe->nrbufs' elements.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

The amount of pipe->buffers is basically controlled by userspace by
fcntl(... F_SETPIPE_SZ ...) so it could be large. High order allocations
could be slow (if memory is heavily fragmented) or may fail if the order
is larger than PAGE_ALLOC_COSTLY_ORDER.

Since the 'bufs' doesn't need to be physically contiguous, use
the kvmalloc_array() to allocate memory. If high order
page isn't available, the kvamalloc*() will fallback to 0-order.

Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

All of fuse uses 64-bit timestamps with the exception of the
fuse_change_attributes(), so let's convert this one as well.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

Use new return type vm_fault_t for fault handler in struct
vm_operations_struct.  For now, this is just documenting that the function
returns a VM_FAULT value rather than an errno.  Once all instances are
converted, vm_fault_t will become a distinct type.

commit 1c8f422059ae ("mm: change return type to vm_fault_t")

Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

The above error path returns with page unlocked, so this place seems also
to behave the same.

Fixes: f8dbdf81821b ("fuse: rework fuse_readpages()")
Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>