Mutex can not be released unless all hid_device members are properly
initialized. Otherwise it would result in a race condition that can
cause NULL pointer kernel panic issue in hidraw_open where it uses
uninitialized 'list' member in list_add_tail().

Signed-off-by: Yonghua Zheng <younghua.zheng@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Print a message when hidraw has been succesfully initialized.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

This patch fixes sending SIGIO from hidraw_report_event by creating a fasync
handler which adds the fasync entry.

Signed-off-by: Andrew Duggan <aduggan@synaptics.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

When nonblock read the condition check (file->f_flags & O_NONBLOCK) always be
true, signal_pending and device exist checking never get a chance to run, so
the user mode code always get EAGAIN even if device removed. move nonblock mode
checking to the last can fix this problem.

Signed-off-by: Founder Fang <founder.fang@gmail.com>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

This basically reverts commit 4fe9f8e203fda. It causes multiple problems,
namely:

- after rmmod/modprobe cycle of bus driver, the input is not claimed any
  more. This is likely because of misplaced hid_hw_close()
- it causes memory corruption on hidraw_list

As original patch author is not responding to requests to fix his patch,
and the original deallocation mechanism is not exposing any problems, I
am reverting back to it.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Conflicts:
	drivers/hid/usbhid/hid-quirks.c

When a device is unplugged, wait for all processes that have opened the device
to close before deallocating the device.

Signed-off-by: Ratan Nalumasu <ratan@google.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Several improvements in error handling:
- do not report success if alloc_chrdev_region() failed
- check for error code of cdev_add()
- use unregister_chrdev_region() instead of unregister_chrdev()
  if class_create() failed

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>