| 1 | /* Changing the per-thread memory protection key, powerpc64 version. |
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| 2 | Copyright (C) 2017-2024 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <http://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | #include <arch-pkey.h> |
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| 20 | #include <errno.h> |
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| 21 | #include <sys/mman.h> |
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| 22 | |
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| 23 | int |
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| 24 | pkey_set (int key, unsigned int rights) |
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| 25 | { |
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| 26 | if (key < 0 || key > PKEY_MAX || rights > 3) |
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| 27 | { |
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| 28 | __set_errno (EINVAL); |
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| 29 | return -1; |
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| 30 | } |
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| 31 | |
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| 32 | /* Translate to AMR bit values. */ |
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| 33 | unsigned long int bits; |
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| 34 | if (rights & PKEY_DISABLE_ACCESS) |
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| 35 | /* The PKEY_DISABLE_WRITE bit does not matter. */ |
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| 36 | bits = PKEY_AMR_READ | PKEY_AMR_WRITE; |
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| 37 | else if (rights == PKEY_DISABLE_WRITE) |
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| 38 | bits = PKEY_AMR_WRITE; |
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| 39 | else |
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| 40 | bits = 0; |
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| 41 | |
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| 42 | unsigned int index = pkey_index (key); |
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| 43 | unsigned long int mask = 3UL << index; |
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| 44 | unsigned long int amr = pkey_read (); |
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| 45 | amr = (amr & ~mask) | (bits << index); |
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| 46 | pkey_write (value: amr); |
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| 47 | return 0; |
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| 48 | } |
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| 49 | |
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