| 1 | /* Copyright (C) 1996-2022 Free Software Foundation, Inc. |
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| 2 | |
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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 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | /* clone() is even more special than fork() as it mucks with stacks |
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| 20 | and invokes a function in the right context after its all over. */ |
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| 21 | |
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| 22 | #include <sysdep.h> |
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| 23 | #define _ERRNO_H 1 |
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| 24 | #include <bits/errno.h> |
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| 25 | |
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| 26 | /* int clone (int (*fn)(void *arg), void *child_stack, int flags, void *arg, |
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| 27 | pid_t *ptid, struct user_desc *tls, pid_t *ctid); |
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| 28 | |
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| 29 | INCOMING: r5 (fn), r6 (child_stack), r7 (flags), r8 (arg), r9 (ptid) |
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| 30 | r10 (tls), 28 (r1) ctid |
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| 31 | |
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| 32 | OUTGOING: |
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| 33 | |
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| 34 | linux: arch/microblaze/entry.S: sys_clone expects |
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| 35 | r5 (flags) r6 (child stack) r7 (stack_size) r8 (ptid)r9 (ctid) |
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| 36 | r10 (tls) |
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| 37 | */ |
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| 38 | |
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| 39 | .text |
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| 40 | ENTRY (__clone) |
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| 41 | addik r3,r0,-EINVAL |
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| 42 | beqi r5,SYSCALL_ERROR_LABEL ; // Invalid func |
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| 43 | beqi r6,SYSCALL_ERROR_LABEL ; // Invalid stack |
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| 44 | addik r6,r6,-8 |
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| 45 | swi r5,r6,0 ; // Push fn onto child's stack |
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| 46 | swi r8,r6,4 ; // Push arg for child |
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| 47 | addk r5,r0,r7 ; // flags for clone() syscall |
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| 48 | addk r7,r0,r0 |
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| 49 | addk r8,r0,r9 ; // parent tid ptr |
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| 50 | lwi r9,r1,28 ; // child tid ptr |
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| 51 | addik r12,r0,SYS_ify(clone) |
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| 52 | brki r14,8 |
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| 53 | addk r0,r0,r0 |
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| 54 | addik r4,r0,-4095 |
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| 55 | cmpu r4,r4,r3 |
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| 56 | bgei r4,SYSCALL_ERROR_LABEL |
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| 57 | beqi r3,L(thread_start) |
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| 58 | rtsd r15,8 |
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| 59 | nop |
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| 60 | |
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| 61 | L(thread_start): |
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| 62 | lwi r12,r1,0 ; // fn |
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| 63 | lwi r5,r1,4 ; // arg |
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| 64 | brald r15,r12 |
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| 65 | nop |
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| 66 | addk r5,r0,r3 |
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| 67 | addik r12,r0,SYS_ify(exit) |
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| 68 | brki r14,8 |
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| 69 | nop |
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| 70 | PSEUDO_END(__clone) |
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| 71 | |
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| 72 | libc_hidden_def (__clone) |
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| 73 | weak_alias (__clone,clone) |
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| 74 | |
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