[v4,0/3] VT: Add ability to get font requirements

Message

Alexey Gladkov April 2, 2024, 5:50 p.m. UTC

We now have KD_FONT_OP_SET_TALL, but in fact such large fonts cannot be
loaded. No console driver supports tall fonts. Unfortunately, userspace
cannot distinguish the lack of support in the driver from errors in the
font itself. In all cases, EINVAL will be returned.

This patchset adds a separate ioctl to obtain the font parameters
supported by the console driver.

v4:
* Rebased on v6.9-rc1 and conflicts have been fixed.
* Do not copy KDFONTINFO data from the userspace.
* Header include/uapi/linux/kd.h uses _IOC macros to define ioctls.

v3:
* Added the use of the in_range macro.
* Squashed the commits that add ioctl to console divers.

v2:
* Instead of the KDFONTOP extension, a new ioctl has been added to
  obtain font information.

Alexey Gladkov (3):
  VT: Use macros to define ioctls
  VT: Add KDFONTINFO ioctl
  VT: Allow to get max font width and height

 drivers/tty/vt/vt.c                 |  24 ++++++
 drivers/tty/vt/vt_ioctl.c           |  11 +++
 drivers/video/console/newport_con.c |  21 +++++-
 drivers/video/console/sticon.c      |  25 ++++++-
 drivers/video/console/vgacon.c      |  21 +++++-
 drivers/video/fbdev/core/fbcon.c    |  16 ++++
 include/linux/console.h             |   3 +
 include/linux/vt_kern.h             |   1 +
 include/uapi/linux/kd.h             | 109 ++++++++++++++++------------
 9 files changed, 176 insertions(+), 55 deletions(-)