1 /* Changing the per-thread memory protection key, powerpc64 version. 2 Copyright (C) 2017-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <http://www.gnu.org/licenses/>. */ 18 19 #include <arch-pkey.h> 20 #include <errno.h> 21 #include <sys/mman.h> 22 23 int pkey_set(int key,unsigned int rights)24pkey_set (int key, unsigned int rights) 25 { 26 if (key < 0 || key > PKEY_MAX || rights > 3) 27 { 28 __set_errno (EINVAL); 29 return -1; 30 } 31 32 /* Translate to AMR bit values. */ 33 unsigned long int bits; 34 if (rights & PKEY_DISABLE_ACCESS) 35 /* The PKEY_DISABLE_WRITE bit does not matter. */ 36 bits = PKEY_AMR_READ | PKEY_AMR_WRITE; 37 else if (rights == PKEY_DISABLE_WRITE) 38 bits = PKEY_AMR_WRITE; 39 else 40 bits = 0; 41 42 unsigned int index = pkey_index (key); 43 unsigned long int mask = 3UL << index; 44 unsigned long int amr = pkey_read (); 45 amr = (amr & ~mask) | (bits << index); 46 pkey_write (amr); 47 return 0; 48 } 49