dsc_overlap setting is not useful anymore for ide-cd so remove
"dsc_overlap" /proc setting, disallow changing the setting through
HDIO_SET_NICE ioctl and cleanup ide_cd{rom_setup,_release}().

Cc: Borislav Petkov <petkovbb@googlemail.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

IDE settings are protected by ide_setting_mtx mutex so there is
no need to hold ide_lock in ide_setting_ioctl(), ide_read_setting()
and ide_proc_unregister_driver().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

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

Add 'unsigned long dev_flags' to ide_drive_t and convert bitfields
to IDE_DFLAG_* flags.

While at it:
- IDE_DFLAG_ADDRESSING -> IDE_DFLAG_LBA48
- fixup some comments
- remove needless g->flags zeroing from ide*_probe()

There should be no functional changes caused by this patch.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Use a special request for serialisation purposes and get rid of the
awkward ide_spin_wait_hwgroup(). This also involves converting the
ide_devset structure so it can be shared by the /proc and the ioctl code.
Signed-off-by: NElias Oltmanns <eo@nebensachen.de>
[bart: use rq->cmd[] directly]
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

* Move ioctls handling to ide-ioctls.c
  (except HDIO_DRIVE_TASKFILE for now).

* Make ide_{cmd,task}() static.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>