Build failure with kernel 5.17 due to mm_segment_t

[bulvara]

I'm using kernel 5.17.12 and the build fails.

./gtp5g.c: In Funktion »unix_sock_send«:
./gtp5g.c:362:5: Fehler: unbekannter Typname: »mm_segment_t«
  362 |     mm_segment_t oldfs;
      |     ^~~~~~~~~~~~
./gtp5g.c:436:13: Error [-Werror=implicit-function-declaration]
  436 |     oldfs = force_uaccess_begin();
      |             ^~~~~~~~~~~~~~~~~~~
      |             user_access_begin
./gtp5g.c:446:5: Error [-Werror=implicit-function-declaration]
  446 |     force_uaccess_end(oldfs);
      |     ^~~~~~~~~~~~~~~~~
      |     file_accessed

The implicit-function-declaration bugs are just follow-ups on the first one.

I've found https://lore.kernel.org/lkml/[e-mail]/ but am not wise enough to fix this. Do you have a solution?