| yuezonghe | 824eb0c | 2024-06-27 02:32:26 -0700 | [diff] [blame] | 1 | /* Copyright (C) 1999, 2000, 2003, 2004, 2007 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | |
| 4 | The GNU C Library is free software; you can redistribute it and/or |
| 5 | modify it under the terms of the GNU Lesser General Public |
| 6 | License as published by the Free Software Foundation; either |
| 7 | version 2.1 of the License, or (at your option) any later version. |
| 8 | |
| 9 | The GNU C Library is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | Lesser General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU Lesser General Public |
| 15 | License along with the GNU C Library; if not, write to the Free |
| 16 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 17 | 02111-1307 USA. */ |
| 18 | |
| 19 | /* clone() is even more special than fork() as it mucks with stacks |
| 20 | and invokes a function in the right context after its all over. */ |
| 21 | |
| 22 | #include <features.h> |
| 23 | #include <asm/unistd.h> |
| 24 | #include <sysdep.h> |
| 25 | #define _ERRNO_H 1 |
| 26 | #include <bits/errno.h> |
| 27 | #ifdef RESET_PID |
| 28 | #include <tcb-offsets.h> |
| 29 | #endif |
| 30 | /* int clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg, |
| 31 | pid_t *ptid, void *tls, pid_t *ctid); */ |
| 32 | |
| 33 | .text |
| 34 | ENTRY(__clone) |
| 35 | /* sanity check arguments. */ |
| 36 | tst r4, r4 |
| 37 | bt/s 0f |
| 38 | tst r5, r5 |
| 39 | bf 1f |
| 40 | 0: |
| 41 | bra .Lsyscall_error |
| 42 | mov #-EINVAL,r0 |
| 43 | 1: |
| 44 | /* insert the args onto the new stack */ |
| 45 | mov.l r7, @-r5 |
| 46 | /* save the function pointer as the 0th element */ |
| 47 | mov.l r4, @-r5 |
| 48 | |
| 49 | /* do the system call */ |
| 50 | mov r6, r4 |
| 51 | mov.l @r15, r6 |
| 52 | mov.l @(8,r15), r7 |
| 53 | mov.l @(4,r15), r0 |
| 54 | mov #+SYS_ify(clone), r3 |
| 55 | trapa #0x15 |
| 56 | mov r0, r1 |
| 57 | mov #-12, r2 |
| 58 | shad r2, r1 |
| 59 | not r1, r1 // r1=0 means r0 = -1 to -4095 |
| 60 | tst r1, r1 // i.e. error in linux |
| 61 | bf .Lclone_end |
| 62 | .Lsyscall_error: |
| 63 | SYSCALL_ERROR_HANDLER |
| 64 | .Lclone_end: |
| 65 | tst r0, r0 |
| 66 | bt 2f |
| 67 | .Lpseudo_end: |
| 68 | rts |
| 69 | nop |
| 70 | 2: |
| 71 | /* terminate the stack frame */ |
| 72 | mov #0, r14 |
| 73 | #ifdef RESET_PID |
| 74 | mov r4, r0 |
| 75 | shlr16 r0 |
| 76 | tst #1, r0 // CLONE_THREAD = (1 << 16) |
| 77 | bf/s 4f |
| 78 | mov r4, r0 |
| 79 | /* new pid */ |
| 80 | shlr8 r0 |
| 81 | tst #1, r0 // CLONE_VM = (1 << 8) |
| 82 | bf/s 3f |
| 83 | mov #-1, r0 |
| 84 | mov #+SYS_ify(getpid), r3 |
| 85 | trapa #0x15 |
| 86 | 3: |
| 87 | stc gbr, r1 |
| 88 | mov.w .Lpidoff, r2 |
| 89 | add r1, r2 |
| 90 | mov.l r0, @r2 |
| 91 | mov.w .Ltidoff, r2 |
| 92 | add r1, r2 |
| 93 | mov.l r0, @r2 |
| 94 | 4: |
| 95 | #endif |
| 96 | /* thread starts */ |
| 97 | mov.l @r15, r1 |
| 98 | jsr @r1 |
| 99 | mov.l @(4,r15), r4 |
| 100 | |
| 101 | /* we are done, passing the return value through r0 */ |
| 102 | mov.l .L3, r1 |
| 103 | #ifdef SHARED |
| 104 | mov.l r12, @-r15 |
| 105 | sts.l pr, @-r15 |
| 106 | mov r0, r4 |
| 107 | mova .LG, r0 |
| 108 | mov.l .LG, r12 |
| 109 | add r0, r12 |
| 110 | mova .L3, r0 |
| 111 | add r0, r1 |
| 112 | jsr @r1 |
| 113 | nop |
| 114 | lds.l @r15+, pr |
| 115 | rts |
| 116 | mov.l @r15+, r12 |
| 117 | #else |
| 118 | jmp @r1 |
| 119 | mov r0, r4 |
| 120 | #endif |
| 121 | .align 2 |
| 122 | .LG: |
| 123 | .long _GLOBAL_OFFSET_TABLE_ |
| 124 | .L3: |
| 125 | .long PLTJMP(C_SYMBOL_NAME(_exit)) |
| 126 | #ifdef RESET_PID |
| 127 | .Lpidoff: |
| 128 | .word PID - TLS_PRE_TCB_SIZE |
| 129 | .Ltidoff: |
| 130 | .word TID - TLS_PRE_TCB_SIZE |
| 131 | #endif |
| 132 | PSEUDO_END (__clone) |
| 133 | |
| 134 | weak_alias (__clone, clone) |