Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 | 2 | /* |
cbdc2292 | 3 | * This file handles the architecture dependent parts of process handling. |
1da177e4 | 4 | * |
a53c8fab | 5 | * Copyright IBM Corp. 1999, 2009 |
cbdc2292 HC |
6 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>, |
7 | * Hartmut Penner <hp@de.ibm.com>, | |
8 | * Denis Joseph Barrow, | |
1da177e4 LT |
9 | */ |
10 | ||
ca21872e | 11 | #include <linux/elf-randomize.h> |
1da177e4 LT |
12 | #include <linux/compiler.h> |
13 | #include <linux/cpu.h> | |
1da177e4 | 14 | #include <linux/sched.h> |
b17b0153 | 15 | #include <linux/sched/debug.h> |
29930025 | 16 | #include <linux/sched/task.h> |
68db0cf1 | 17 | #include <linux/sched/task_stack.h> |
1da177e4 LT |
18 | #include <linux/kernel.h> |
19 | #include <linux/mm.h> | |
638ad34a | 20 | #include <linux/elfcore.h> |
1da177e4 | 21 | #include <linux/smp.h> |
5a0e3ad6 | 22 | #include <linux/slab.h> |
1da177e4 | 23 | #include <linux/interrupt.h> |
5a62b192 | 24 | #include <linux/tick.h> |
9887a1fc | 25 | #include <linux/personality.h> |
26689452 | 26 | #include <linux/syscalls.h> |
3e86a8c6 | 27 | #include <linux/compat.h> |
860dba45 | 28 | #include <linux/kprobes.h> |
9887a1fc | 29 | #include <linux/random.h> |
3994a52b | 30 | #include <linux/export.h> |
0ac27779 | 31 | #include <linux/init_task.h> |
2317b07d | 32 | #include <asm/cpu_mf.h> |
1da177e4 LT |
33 | #include <asm/io.h> |
34 | #include <asm/processor.h> | |
27f6b416 | 35 | #include <asm/vtimer.h> |
f6e38691 | 36 | #include <asm/exec.h> |
1da177e4 | 37 | #include <asm/irq.h> |
f5daba1d | 38 | #include <asm/nmi.h> |
da7f51c1 | 39 | #include <asm/smp.h> |
a0616cde | 40 | #include <asm/switch_to.h> |
e4b8b3f3 | 41 | #include <asm/runtime_instr.h> |
a806170e | 42 | #include "entry.h" |
1da177e4 | 43 | |
94c12cc7 | 44 | asmlinkage void ret_from_fork(void) asm ("ret_from_fork"); |
1da177e4 | 45 | |
7a5388de | 46 | extern void kernel_thread_starter(void); |
1da177e4 | 47 | |
1da177e4 LT |
48 | void flush_thread(void) |
49 | { | |
1da177e4 LT |
50 | } |
51 | ||
2317b07d MS |
52 | void arch_setup_new_exec(void) |
53 | { | |
54 | if (S390_lowcore.current_pid != current->pid) { | |
55 | S390_lowcore.current_pid = current->pid; | |
56 | if (test_facility(40)) | |
57 | lpp(&S390_lowcore.lpp); | |
58 | } | |
59 | } | |
60 | ||
6a039eab HB |
61 | void arch_release_task_struct(struct task_struct *tsk) |
62 | { | |
8d9047f8 | 63 | runtime_instr_release(tsk); |
7b83c629 | 64 | guarded_storage_release(tsk); |
155e839a HB |
65 | } |
66 | ||
67 | int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) | |
68 | { | |
9977e886 HB |
69 | /* |
70 | * Save the floating-point or vector register state of the current | |
b5510d9b HB |
71 | * task and set the CIF_FPU flag to lazy restore the FPU register |
72 | * state when returning to user space. | |
9977e886 | 73 | */ |
d0164ee2 | 74 | save_fpu_regs(); |
b5510d9b | 75 | |
3f6813b9 MS |
76 | memcpy(dst, src, arch_task_struct_size); |
77 | dst->thread.fpu.regs = dst->thread.fpu.fprs; | |
155e839a | 78 | return 0; |
6a039eab | 79 | } |
6a039eab | 80 | |
f50c0e63 HC |
81 | int copy_thread_tls(unsigned long clone_flags, unsigned long new_stackp, |
82 | unsigned long arg, struct task_struct *p, unsigned long tls) | |
1da177e4 | 83 | { |
cbdc2292 HC |
84 | struct fake_frame |
85 | { | |
86 | struct stack_frame sf; | |
87 | struct pt_regs childregs; | |
88 | } *frame; | |
89 | ||
90 | frame = container_of(task_pt_regs(p), struct fake_frame, childregs); | |
91 | p->thread.ksp = (unsigned long) frame; | |
f9a7e025 AV |
92 | /* Save access registers to new thread structure. */ |
93 | save_access_regs(&p->thread.acrs[0]); | |
94 | /* start new process with ar4 pointing to the correct address space */ | |
95 | p->thread.mm_segment = get_fs(); | |
96 | /* Don't copy debug registers */ | |
97 | memset(&p->thread.per_user, 0, sizeof(p->thread.per_user)); | |
98 | memset(&p->thread.per_event, 0, sizeof(p->thread.per_event)); | |
99 | clear_tsk_thread_flag(p, TIF_SINGLE_STEP); | |
a1c5befc | 100 | p->thread.per_flags = 0; |
f9a7e025 | 101 | /* Initialize per thread user and system timer values */ |
90c53e65 | 102 | p->thread.user_timer = 0; |
3c915bdc | 103 | p->thread.guest_timer = 0; |
90c53e65 | 104 | p->thread.system_timer = 0; |
3c915bdc MS |
105 | p->thread.hardirq_timer = 0; |
106 | p->thread.softirq_timer = 0; | |
1da177e4 | 107 | |
f9a7e025 | 108 | frame->sf.back_chain = 0; |
cbdc2292 HC |
109 | /* new return point is ret_from_fork */ |
110 | frame->sf.gprs[8] = (unsigned long) ret_from_fork; | |
cbdc2292 HC |
111 | /* fake return stack for resume(), don't go back to schedule */ |
112 | frame->sf.gprs[9] = (unsigned long) frame; | |
1da177e4 | 113 | |
f9a7e025 | 114 | /* Store access registers to kernel stack of new process. */ |
87f1ca8f | 115 | if (unlikely(p->flags & PF_KTHREAD)) { |
f9a7e025 AV |
116 | /* kernel thread */ |
117 | memset(&frame->childregs, 0, sizeof(struct pt_regs)); | |
e258d719 | 118 | frame->childregs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_DAT | |
f9a7e025 | 119 | PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK; |
fecc868a | 120 | frame->childregs.psw.addr = |
f9a7e025 AV |
121 | (unsigned long) kernel_thread_starter; |
122 | frame->childregs.gprs[9] = new_stackp; /* function */ | |
123 | frame->childregs.gprs[10] = arg; | |
124 | frame->childregs.gprs[11] = (unsigned long) do_exit; | |
125 | frame->childregs.orig_gpr2 = -1; | |
126 | ||
127 | return 0; | |
128 | } | |
87f1ca8f | 129 | frame->childregs = *current_pt_regs(); |
f9a7e025 | 130 | frame->childregs.gprs[2] = 0; /* child returns 0 on fork. */ |
d3a73acb | 131 | frame->childregs.flags = 0; |
87f1ca8f AV |
132 | if (new_stackp) |
133 | frame->childregs.gprs[15] = new_stackp; | |
1da177e4 | 134 | |
e4b8b3f3 JG |
135 | /* Don't copy runtime instrumentation info */ |
136 | p->thread.ri_cb = NULL; | |
e4b8b3f3 | 137 | frame->childregs.psw.mask &= ~PSW_MASK_RI; |
916cda1a MS |
138 | /* Don't copy guarded storage control block */ |
139 | p->thread.gs_cb = NULL; | |
140 | p->thread.gs_bc_cb = NULL; | |
e4b8b3f3 | 141 | |
1da177e4 LT |
142 | /* Set a new TLS ? */ |
143 | if (clone_flags & CLONE_SETTLS) { | |
7757591a | 144 | if (is_compat_task()) { |
87f1ca8f | 145 | p->thread.acrs[0] = (unsigned int)tls; |
1da177e4 | 146 | } else { |
87f1ca8f AV |
147 | p->thread.acrs[0] = (unsigned int)(tls >> 32); |
148 | p->thread.acrs[1] = (unsigned int)tls; | |
1da177e4 LT |
149 | } |
150 | } | |
cbdc2292 | 151 | return 0; |
1da177e4 LT |
152 | } |
153 | ||
03ff9a23 MS |
154 | asmlinkage void execve_tail(void) |
155 | { | |
904818e2 | 156 | current->thread.fpu.fpc = 0; |
e47994dd | 157 | asm volatile("sfpc %0" : : "d" (0)); |
1da177e4 LT |
158 | } |
159 | ||
1da177e4 LT |
160 | /* |
161 | * fill in the FPU structure for a core dump. | |
162 | */ | |
163 | int dump_fpu (struct pt_regs * regs, s390_fp_regs *fpregs) | |
164 | { | |
d0164ee2 | 165 | save_fpu_regs(); |
9977e886 HB |
166 | fpregs->fpc = current->thread.fpu.fpc; |
167 | fpregs->pad = 0; | |
b5510d9b | 168 | if (MACHINE_HAS_VX) |
9977e886 HB |
169 | convert_vx_to_fp((freg_t *)&fpregs->fprs, |
170 | current->thread.fpu.vxrs); | |
171 | else | |
172 | memcpy(&fpregs->fprs, current->thread.fpu.fprs, | |
173 | sizeof(fpregs->fprs)); | |
1da177e4 LT |
174 | return 1; |
175 | } | |
1485c5c8 | 176 | EXPORT_SYMBOL(dump_fpu); |
1da177e4 | 177 | |
1da177e4 LT |
178 | unsigned long get_wchan(struct task_struct *p) |
179 | { | |
180 | struct stack_frame *sf, *low, *high; | |
181 | unsigned long return_address; | |
182 | int count; | |
183 | ||
30af7120 | 184 | if (!p || p == current || p->state == TASK_RUNNING || !task_stack_page(p)) |
1da177e4 | 185 | return 0; |
30af7120 AV |
186 | low = task_stack_page(p); |
187 | high = (struct stack_frame *) task_pt_regs(p); | |
9cb1ccec | 188 | sf = (struct stack_frame *) p->thread.ksp; |
1da177e4 LT |
189 | if (sf <= low || sf > high) |
190 | return 0; | |
191 | for (count = 0; count < 16; count++) { | |
9cb1ccec | 192 | sf = (struct stack_frame *) sf->back_chain; |
1da177e4 LT |
193 | if (sf <= low || sf > high) |
194 | return 0; | |
9cb1ccec | 195 | return_address = sf->gprs[8]; |
1da177e4 LT |
196 | if (!in_sched_functions(return_address)) |
197 | return return_address; | |
198 | } | |
199 | return 0; | |
200 | } | |
9887a1fc HC |
201 | |
202 | unsigned long arch_align_stack(unsigned long sp) | |
203 | { | |
204 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) | |
205 | sp -= get_random_int() & ~PAGE_MASK; | |
206 | return sp & ~0xf; | |
207 | } | |
33519182 HC |
208 | |
209 | static inline unsigned long brk_rnd(void) | |
210 | { | |
c7e8b2c2 | 211 | return (get_random_int() & BRK_RND_MASK) << PAGE_SHIFT; |
33519182 HC |
212 | } |
213 | ||
214 | unsigned long arch_randomize_brk(struct mm_struct *mm) | |
215 | { | |
9efe4f29 | 216 | unsigned long ret; |
33519182 | 217 | |
9efe4f29 MS |
218 | ret = PAGE_ALIGN(mm->brk + brk_rnd()); |
219 | return (ret > mm->brk) ? ret : mm->brk; | |
33519182 | 220 | } |
b5a882fc HC |
221 | |
222 | void set_fs_fixup(void) | |
223 | { | |
224 | struct pt_regs *regs = current_pt_regs(); | |
225 | static bool warned; | |
226 | ||
227 | set_fs(USER_DS); | |
228 | if (warned) | |
229 | return; | |
230 | WARN(1, "Unbalanced set_fs - int code: 0x%x\n", regs->int_code); | |
231 | show_registers(regs); | |
232 | warned = true; | |
233 | } |