1 // SPDX-License-Identifier: GPL-2.0-or-later !! 1 // SPDX-License-Identifier: GPL-2.0
2 /* 2 /*
3 * Copyright (C) 2009 Sunplus Core Technology !! 3 * linux/arch/m68k/kernel/process.c
4 * Chen Liqin <liqin.chen@sunplusct.com> !! 4 *
5 * Lennox Wu <lennox.wu@sunplusct.com> !! 5 * Copyright (C) 1995 Hamish Macdonald
6 * Copyright (C) 2012 Regents of the Universit !! 6 *
7 * Copyright (C) 2017 SiFive !! 7 * 68060 fixes by Jesper Skov
8 */ 8 */
9 9
10 #include <linux/cpu.h> !! 10 /*
11 #include <linux/kernel.h> !! 11 * This file handles the architecture-dependent parts of process handling..
>> 12 */
>> 13
>> 14 #include <linux/errno.h>
>> 15 #include <linux/module.h>
12 #include <linux/sched.h> 16 #include <linux/sched.h>
13 #include <linux/sched/debug.h> 17 #include <linux/sched/debug.h>
>> 18 #include <linux/sched/task.h>
14 #include <linux/sched/task_stack.h> 19 #include <linux/sched/task_stack.h>
15 #include <linux/tick.h> !! 20 #include <linux/kernel.h>
>> 21 #include <linux/mm.h>
>> 22 #include <linux/slab.h>
>> 23 #include <linux/fs.h>
>> 24 #include <linux/smp.h>
>> 25 #include <linux/stddef.h>
>> 26 #include <linux/unistd.h>
16 #include <linux/ptrace.h> 27 #include <linux/ptrace.h>
>> 28 #include <linux/user.h>
>> 29 #include <linux/reboot.h>
>> 30 #include <linux/init_task.h>
>> 31 #include <linux/mqueue.h>
>> 32 #include <linux/rcupdate.h>
>> 33 #include <linux/syscalls.h>
17 #include <linux/uaccess.h> 34 #include <linux/uaccess.h>
18 #include <linux/personality.h> !! 35 #include <linux/elfcore.h>
19 36
20 #include <asm/unistd.h> !! 37 #include <asm/traps.h>
21 #include <asm/processor.h> !! 38 #include <asm/machdep.h>
22 #include <asm/csr.h> !! 39 #include <asm/setup.h>
23 #include <asm/stacktrace.h> !! 40
24 #include <asm/string.h> !! 41 #include "process.h"
25 #include <asm/switch_to.h> <<
26 #include <asm/thread_info.h> <<
27 #include <asm/cpuidle.h> <<
28 #include <asm/vector.h> <<
29 #include <asm/cpufeature.h> <<
30 #include <asm/exec.h> <<
31 <<
32 #if defined(CONFIG_STACKPROTECTOR) && !defined <<
33 #include <linux/stackprotector.h> <<
34 unsigned long __stack_chk_guard __read_mostly; <<
35 EXPORT_SYMBOL(__stack_chk_guard); <<
36 #endif <<
37 42
38 extern asmlinkage void ret_from_fork(void); !! 43 asmlinkage void ret_from_fork(void);
>> 44 asmlinkage void ret_from_kernel_thread(void);
39 45
40 void noinstr arch_cpu_idle(void) !! 46 void arch_cpu_idle(void)
41 { 47 {
42 cpu_do_idle(); !! 48 #if defined(MACH_ATARI_ONLY)
>> 49 /* block out HSYNC on the atari (falcon) */
>> 50 __asm__("stop #0x2200" : : : "cc");
>> 51 #else
>> 52 __asm__("stop #0x2000" : : : "cc");
>> 53 #endif
43 } 54 }
44 55
45 int set_unalign_ctl(struct task_struct *tsk, u !! 56 void machine_restart(char * __unused)
46 { 57 {
47 if (!unaligned_ctl_available()) !! 58 if (mach_reset)
48 return -EINVAL; !! 59 mach_reset();
49 !! 60 for (;;);
50 tsk->thread.align_ctl = val; <<
51 return 0; <<
52 } 61 }
53 62
54 int get_unalign_ctl(struct task_struct *tsk, u !! 63 void machine_halt(void)
55 { 64 {
56 if (!unaligned_ctl_available()) !! 65 if (mach_halt)
57 return -EINVAL; !! 66 mach_halt();
58 !! 67 for (;;);
59 return put_user(tsk->thread.align_ctl, <<
60 } 68 }
61 69
62 void __show_regs(struct pt_regs *regs) !! 70 void machine_power_off(void)
63 { 71 {
64 show_regs_print_info(KERN_DEFAULT); !! 72 do_kernel_power_off();
65 !! 73 for (;;);
66 if (!user_mode(regs)) { !! 74 }
67 pr_cont("epc : %pS\n", (void * <<
68 pr_cont(" ra : %pS\n", (void * <<
69 } <<
70 75
71 pr_cont("epc : " REG_FMT " ra : " REG_ !! 76 void (*pm_power_off)(void);
72 regs->epc, regs->ra, regs->sp) !! 77 EXPORT_SYMBOL(pm_power_off);
73 pr_cont(" gp : " REG_FMT " tp : " REG_ <<
74 regs->gp, regs->tp, regs->t0); <<
75 pr_cont(" t1 : " REG_FMT " t2 : " REG_ <<
76 regs->t1, regs->t2, regs->s0); <<
77 pr_cont(" s1 : " REG_FMT " a0 : " REG_ <<
78 regs->s1, regs->a0, regs->a1); <<
79 pr_cont(" a2 : " REG_FMT " a3 : " REG_ <<
80 regs->a2, regs->a3, regs->a4); <<
81 pr_cont(" a5 : " REG_FMT " a6 : " REG_ <<
82 regs->a5, regs->a6, regs->a7); <<
83 pr_cont(" s2 : " REG_FMT " s3 : " REG_ <<
84 regs->s2, regs->s3, regs->s4); <<
85 pr_cont(" s5 : " REG_FMT " s6 : " REG_ <<
86 regs->s5, regs->s6, regs->s7); <<
87 pr_cont(" s8 : " REG_FMT " s9 : " REG_ <<
88 regs->s8, regs->s9, regs->s10) <<
89 pr_cont(" s11: " REG_FMT " t3 : " REG_ <<
90 regs->s11, regs->t3, regs->t4) <<
91 pr_cont(" t5 : " REG_FMT " t6 : " REG_ <<
92 regs->t5, regs->t6); <<
93 78
94 pr_cont("status: " REG_FMT " badaddr: !! 79 void show_regs(struct pt_regs * regs)
95 regs->status, regs->badaddr, r <<
96 } <<
97 void show_regs(struct pt_regs *regs) <<
98 { 80 {
99 __show_regs(regs); !! 81 pr_info("Format %02x Vector: %04x PC: %08lx Status: %04x %s\n",
100 if (!user_mode(regs)) !! 82 regs->format, regs->vector, regs->pc, regs->sr,
101 dump_backtrace(regs, NULL, KER !! 83 print_tainted());
>> 84 pr_info("ORIG_D0: %08lx D0: %08lx A2: %08lx A1: %08lx\n",
>> 85 regs->orig_d0, regs->d0, regs->a2, regs->a1);
>> 86 pr_info("A0: %08lx D5: %08lx D4: %08lx\n", regs->a0, regs->d5,
>> 87 regs->d4);
>> 88 pr_info("D3: %08lx D2: %08lx D1: %08lx\n", regs->d3, regs->d2,
>> 89 regs->d1);
>> 90 if (!(regs->sr & PS_S))
>> 91 pr_info("USP: %08lx\n", rdusp());
102 } 92 }
103 93
104 unsigned long arch_align_stack(unsigned long s !! 94 void flush_thread(void)
105 { 95 {
106 if (!(current->personality & ADDR_NO_R !! 96 current->thread.fc = USER_DATA;
107 sp -= get_random_u32_below(PAG !! 97 #ifdef CONFIG_FPU
108 return sp & ~0xf; !! 98 if (!FPU_IS_EMU) {
>> 99 unsigned long zero = 0;
>> 100 asm volatile("frestore %0": :"m" (zero));
>> 101 }
>> 102 #endif
109 } 103 }
110 104
111 #ifdef CONFIG_COMPAT !! 105 /*
112 static bool compat_mode_supported __read_mostl !! 106 * Why not generic sys_clone, you ask? m68k passes all arguments on stack.
113 !! 107 * And we need all registers saved, which means a bunch of stuff pushed
114 bool compat_elf_check_arch(Elf32_Ehdr *hdr) !! 108 * on top of pt_regs, which means that sys_clone() arguments would be
>> 109 * buried. We could, of course, copy them, but it's too costly for no
>> 110 * good reason - generic clone() would have to copy them *again* for
>> 111 * kernel_clone() anyway. So in this case it's actually better to pass pt_regs *
>> 112 * and extract arguments for kernel_clone() from there. Eventually we might
>> 113 * go for calling kernel_clone() directly from the wrapper, but only after we
>> 114 * are finished with kernel_clone() prototype conversion.
>> 115 */
>> 116 asmlinkage int m68k_clone(struct pt_regs *regs)
115 { 117 {
116 return compat_mode_supported && !! 118 /* regs will be equal to current_pt_regs() */
117 hdr->e_machine == EM_RISCV && !! 119 struct kernel_clone_args args = {
118 hdr->e_ident[EI_CLASS] == ELFCL !! 120 .flags = (u32)(regs->d1) & ~CSIGNAL,
>> 121 .pidfd = (int __user *)regs->d3,
>> 122 .child_tid = (int __user *)regs->d4,
>> 123 .parent_tid = (int __user *)regs->d3,
>> 124 .exit_signal = regs->d1 & CSIGNAL,
>> 125 .stack = regs->d2,
>> 126 .tls = regs->d5,
>> 127 };
>> 128
>> 129 return kernel_clone(&args);
119 } 130 }
120 131
121 static int __init compat_mode_detect(void) !! 132 /*
>> 133 * Because extra registers are saved on the stack after the sys_clone3()
>> 134 * arguments, this C wrapper extracts them from pt_regs * and then calls the
>> 135 * generic sys_clone3() implementation.
>> 136 */
>> 137 asmlinkage int m68k_clone3(struct pt_regs *regs)
122 { 138 {
123 unsigned long tmp = csr_read(CSR_STATU !! 139 return sys_clone3((struct clone_args __user *)regs->d1, regs->d2);
124 <<
125 csr_write(CSR_STATUS, (tmp & ~SR_UXL) <<
126 compat_mode_supported = <<
127 (csr_read(CSR_STATUS) <<
128 <<
129 csr_write(CSR_STATUS, tmp); <<
130 <<
131 pr_info("riscv: ELF compat mode %s", <<
132 compat_mode_supported <<
133 <<
134 return 0; <<
135 } 140 }
136 early_initcall(compat_mode_detect); <<
137 #endif <<
138 141
139 void start_thread(struct pt_regs *regs, unsign !! 142 int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
140 unsigned long sp) <<
141 { 143 {
142 regs->status = SR_PIE; !! 144 unsigned long clone_flags = args->flags;
143 if (has_fpu()) { !! 145 unsigned long usp = args->stack;
144 regs->status |= SR_FS_INITIAL; !! 146 unsigned long tls = args->tls;
145 /* !! 147 struct fork_frame {
146 * Restore the initial value t !! 148 struct switch_stack sw;
147 * before starting the user pr !! 149 struct pt_regs regs;
148 */ !! 150 } *frame;
149 fstate_restore(current, regs); <<
150 } <<
151 regs->epc = pc; <<
152 regs->sp = sp; <<
153 151
154 #ifdef CONFIG_64BIT !! 152 frame = (struct fork_frame *) (task_stack_page(p) + THREAD_SIZE) - 1;
155 regs->status &= ~SR_UXL; <<
156 153
157 if (is_compat_task()) !! 154 p->thread.ksp = (unsigned long)frame;
158 regs->status |= SR_UXL_32; !! 155 p->thread.esp0 = (unsigned long)&frame->regs;
159 else <<
160 regs->status |= SR_UXL_64; <<
161 #endif <<
162 } <<
163 156
164 void flush_thread(void) <<
165 { <<
166 #ifdef CONFIG_FPU <<
167 /* 157 /*
168 * Reset FPU state and context !! 158 * Must save the current SFC/DFC value, NOT the value when
169 * frm: round to nearest, ties to !! 159 * the parent was last descheduled - RGH 10-08-96
170 * fflags: accrued exceptions cle <<
171 */ 160 */
172 fstate_off(current, task_pt_regs(curre !! 161 p->thread.fc = USER_DATA;
173 memset(¤t->thread.fstate, 0, siz <<
174 #endif <<
175 #ifdef CONFIG_RISCV_ISA_V <<
176 /* Reset vector state */ <<
177 riscv_v_vstate_ctrl_init(current); <<
178 riscv_v_vstate_off(task_pt_regs(curren <<
179 kfree(current->thread.vstate.datap); <<
180 memset(¤t->thread.vstate, 0, siz <<
181 clear_tsk_thread_flag(current, TIF_RIS <<
182 #endif <<
183 } <<
184 162
185 void arch_release_task_struct(struct task_stru !! 163 if (unlikely(args->fn)) {
186 { !! 164 /* kernel thread */
187 /* Free the vector context of datap. * !! 165 memset(frame, 0, sizeof(struct fork_frame));
188 if (has_vector()) !! 166 frame->regs.sr = PS_S;
189 riscv_v_thread_free(tsk); !! 167 frame->sw.a3 = (unsigned long)args->fn;
190 } !! 168 frame->sw.d7 = (unsigned long)args->fn_arg;
>> 169 frame->sw.retpc = (unsigned long)ret_from_kernel_thread;
>> 170 p->thread.usp = 0;
>> 171 return 0;
>> 172 }
>> 173 memcpy(frame, container_of(current_pt_regs(), struct fork_frame, regs),
>> 174 sizeof(struct fork_frame));
>> 175 frame->regs.d0 = 0;
>> 176 frame->sw.retpc = (unsigned long)ret_from_fork;
>> 177 p->thread.usp = usp ?: rdusp();
191 178
192 int arch_dup_task_struct(struct task_struct *d !! 179 if (clone_flags & CLONE_SETTLS)
193 { !! 180 task_thread_info(p)->tp_value = tls;
194 fstate_save(src, task_pt_regs(src)); !! 181
195 *dst = *src; !! 182 #ifdef CONFIG_FPU
196 /* clear entire V context, including d !! 183 if (!FPU_IS_EMU) {
197 memset(&dst->thread.vstate, 0, sizeof( !! 184 /* Copy the current fpu state */
198 memset(&dst->thread.kernel_vstate, 0, !! 185 asm volatile ("fsave %0" : : "m" (p->thread.fpstate[0]) : "memory");
199 clear_tsk_thread_flag(dst, TIF_RISCV_V !! 186
>> 187 if (!CPU_IS_060 ? p->thread.fpstate[0] : p->thread.fpstate[2]) {
>> 188 if (CPU_IS_COLDFIRE) {
>> 189 asm volatile ("fmovemd %/fp0-%/fp7,%0\n\t"
>> 190 "fmovel %/fpiar,%1\n\t"
>> 191 "fmovel %/fpcr,%2\n\t"
>> 192 "fmovel %/fpsr,%3"
>> 193 :
>> 194 : "m" (p->thread.fp[0]),
>> 195 "m" (p->thread.fpcntl[0]),
>> 196 "m" (p->thread.fpcntl[1]),
>> 197 "m" (p->thread.fpcntl[2])
>> 198 : "memory");
>> 199 } else {
>> 200 asm volatile ("fmovemx %/fp0-%/fp7,%0\n\t"
>> 201 "fmoveml %/fpiar/%/fpcr/%/fpsr,%1"
>> 202 :
>> 203 : "m" (p->thread.fp[0]),
>> 204 "m" (p->thread.fpcntl[0])
>> 205 : "memory");
>> 206 }
>> 207 }
>> 208
>> 209 /* Restore the state in case the fpu was busy */
>> 210 asm volatile ("frestore %0" : : "m" (p->thread.fpstate[0]));
>> 211 }
>> 212 #endif /* CONFIG_FPU */
200 213
201 return 0; 214 return 0;
202 } 215 }
203 216
204 int copy_thread(struct task_struct *p, const s !! 217 /* Fill in the fpu structure for a core dump. */
>> 218 int elf_core_copy_task_fpregs(struct task_struct *t, elf_fpregset_t *fpu)
205 { 219 {
206 unsigned long clone_flags = args->flag !! 220 if (FPU_IS_EMU) {
207 unsigned long usp = args->stack; !! 221 int i;
208 unsigned long tls = args->tls; <<
209 struct pt_regs *childregs = task_pt_re <<
210 222
211 memset(&p->thread.s, 0, sizeof(p->thre !! 223 memcpy(fpu->fpcntl, current->thread.fpcntl, 12);
>> 224 memcpy(fpu->fpregs, current->thread.fp, 96);
>> 225 /* Convert internal fpu reg representation
>> 226 * into long double format
>> 227 */
>> 228 for (i = 0; i < 24; i += 3)
>> 229 fpu->fpregs[i] = ((fpu->fpregs[i] & 0xffff0000) << 15) |
>> 230 ((fpu->fpregs[i] & 0x0000ffff) << 16);
>> 231 return 1;
>> 232 }
212 233
213 /* p->thread holds context to be resto !! 234 if (IS_ENABLED(CONFIG_FPU)) {
214 if (unlikely(args->fn)) { !! 235 char fpustate[216];
215 /* Kernel thread */ !! 236
216 memset(childregs, 0, sizeof(st !! 237 /* First dump the fpu context to avoid protocol violation. */
217 /* Supervisor/Machine, irqs on !! 238 asm volatile ("fsave %0" :: "m" (fpustate[0]) : "memory");
218 childregs->status = SR_PP | SR !! 239 if (!CPU_IS_060 ? !fpustate[0] : !fpustate[2])
219 !! 240 return 0;
220 p->thread.s[0] = (unsigned lon !! 241
221 p->thread.s[1] = (unsigned lon !! 242 if (CPU_IS_COLDFIRE) {
222 } else { !! 243 asm volatile ("fmovel %/fpiar,%0\n\t"
223 *childregs = *(current_pt_regs !! 244 "fmovel %/fpcr,%1\n\t"
224 /* Turn off status.VS */ !! 245 "fmovel %/fpsr,%2\n\t"
225 riscv_v_vstate_off(childregs); !! 246 "fmovemd %/fp0-%/fp7,%3"
226 if (usp) /* User fork */ !! 247 :
227 childregs->sp = usp; !! 248 : "m" (fpu->fpcntl[0]),
228 if (clone_flags & CLONE_SETTLS !! 249 "m" (fpu->fpcntl[1]),
229 childregs->tp = tls; !! 250 "m" (fpu->fpcntl[2]),
230 childregs->a0 = 0; /* Return v !! 251 "m" (fpu->fpregs[0])
231 p->thread.s[0] = 0; !! 252 : "memory");
>> 253 } else {
>> 254 asm volatile ("fmovem %/fpiar/%/fpcr/%/fpsr,%0"
>> 255 :
>> 256 : "m" (fpu->fpcntl[0])
>> 257 : "memory");
>> 258 asm volatile ("fmovemx %/fp0-%/fp7,%0"
>> 259 :
>> 260 : "m" (fpu->fpregs[0])
>> 261 : "memory");
>> 262 }
232 } 263 }
233 p->thread.riscv_v_flags = 0; !! 264
234 if (has_vector()) !! 265 return 1;
235 riscv_v_thread_alloc(p); <<
236 p->thread.ra = (unsigned long)ret_from <<
237 p->thread.sp = (unsigned long)childreg <<
238 return 0; <<
239 } 266 }
240 267
241 void __init arch_task_cache_init(void) !! 268 unsigned long __get_wchan(struct task_struct *p)
242 { 269 {
243 riscv_v_setup_ctx_cache(); !! 270 unsigned long fp, pc;
>> 271 unsigned long stack_page;
>> 272 int count = 0;
>> 273
>> 274 stack_page = (unsigned long)task_stack_page(p);
>> 275 fp = ((struct switch_stack *)p->thread.ksp)->a6;
>> 276 do {
>> 277 if (fp < stack_page+sizeof(struct thread_info) ||
>> 278 fp >= 8184+stack_page)
>> 279 return 0;
>> 280 pc = ((unsigned long *)fp)[1];
>> 281 if (!in_sched_functions(pc))
>> 282 return pc;
>> 283 fp = *(unsigned long *) fp;
>> 284 } while (count++ < 16);
>> 285 return 0;
244 } 286 }
245 287
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.