commit f23653fe64479d96910bfda2b700b1af17c991ac upstream.
Fix a user API regression introduced with commit f76edd8f7c ("tty:
cyclades, remove this orphan"), which removed a part of the API and
caused compilation errors for user programs using said part, such as
GCC 9 in its libsanitizer component[1]:
.../libsanitizer/sanitizer_common/sanitizer_platform_limits_posix.cc:160:10: fatal error: linux/cyclades.h: No such file or directory
160 | #include <linux/cyclades.h>
| ^~~~~~~~~~~~~~~~~~
compilation terminated.
make[4]: *** [Makefile:664: sanitizer_platform_limits_posix.lo] Error 1
As the absolute minimum required bring `struct cyclades_monitor' and
ioctl numbers back then so as to make the library build again. Add a
preprocessor warning as to the obsolescence of the features provided.
References:
[1] GCC PR sanitizer/100379, "cyclades.h is removed from linux kernel
header files", <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100379>
Fixes: f76edd8f7c ("tty: cyclades, remove this orphan")
Cc: stable@vger.kernel.org # v5.13+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Maciej W. Rozycki <macro@embecosm.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.20.2201260733430.11348@tpp.orcam.me.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
b51afdc797