Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 | // SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk}) * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de) * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com) * Copyright 2003 PathScale, Inc. */ #include <linux/stddef.h> #include <linux/err.h> #include <linux/hardirq.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/personality.h> #include <linux/proc_fs.h> #include <linux/ptrace.h> #include <linux/random.h> #include <linux/slab.h> #include <linux/sched.h> #include <linux/sched/debug.h> #include <linux/sched/task.h> #include <linux/sched/task_stack.h> #include <linux/seq_file.h> #include <linux/tick.h> #include <linux/threads.h> #include <linux/resume_user_mode.h> #include <asm/current.h> #include <asm/mmu_context.h> #include <linux/uaccess.h> #include <as-layout.h> #include <kern_util.h> #include <os.h> #include <skas.h> #include <registers.h> #include <linux/time-internal.h> /* * This is a per-cpu array. A processor only modifies its entry and it only * cares about its entry, so it's OK if another processor is modifying its * entry. */ struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } }; static inline int external_pid(void) { /* FIXME: Need to look up userspace_pid by cpu */ return userspace_pid[0]; } int pid_to_processor_id(int pid) { int i; for (i = 0; i < ncpus; i++) { if (cpu_tasks[i].pid == pid) return i; } return -1; } void free_stack(unsigned long stack, int order) { free_pages(stack, order); } unsigned long alloc_stack(int order, int atomic) { unsigned long page; gfp_t flags = GFP_KERNEL; if (atomic) flags = GFP_ATOMIC; page = __get_free_pages(flags, order); return page; } static inline void set_current(struct task_struct *task) { cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task) { external_pid(), task }); } extern void arch_switch_to(struct task_struct *to); void *__switch_to(struct task_struct *from, struct task_struct *to) { to->thread.prev_sched = from; set_current(to); switch_threads(&from->thread.switch_buf, &to->thread.switch_buf); arch_switch_to(current); return current->thread.prev_sched; } void interrupt_end(void) { struct pt_regs *regs = ¤t->thread.regs; if (need_resched()) schedule(); if (test_thread_flag(TIF_SIGPENDING) || test_thread_flag(TIF_NOTIFY_SIGNAL)) do_signal(regs); if (test_thread_flag(TIF_NOTIFY_RESUME)) resume_user_mode_work(regs); } int get_current_pid(void) { return task_pid_nr(current); } /* * This is called magically, by its address being stuffed in a jmp_buf * and being longjmp-d to. */ void new_thread_handler(void) { int (*fn)(void *), n; void *arg; if (current->thread.prev_sched != NULL) schedule_tail(current->thread.prev_sched); current->thread.prev_sched = NULL; fn = current->thread.request.u.thread.proc; arg = current->thread.request.u.thread.arg; /* * callback returns only if the kernel thread execs a process */ n = fn(arg); userspace(¤t->thread.regs.regs, current_thread_info()->aux_fp_regs); } /* Called magically, see new_thread_handler above */ void fork_handler(void) { force_flush_all(); schedule_tail(current->thread.prev_sched); /* * XXX: if interrupt_end() calls schedule, this call to * arch_switch_to isn't needed. We could want to apply this to * improve performance. -bb */ arch_switch_to(current); current->thread.prev_sched = NULL; userspace(¤t->thread.regs.regs, current_thread_info()->aux_fp_regs); } int copy_thread(struct task_struct * p, const struct kernel_clone_args *args) { unsigned long clone_flags = args->flags; unsigned long sp = args->stack; unsigned long tls = args->tls; void (*handler)(void); int ret = 0; p->thread = (struct thread_struct) INIT_THREAD; if (!args->fn) { memcpy(&p->thread.regs.regs, current_pt_regs(), sizeof(p->thread.regs.regs)); PT_REGS_SET_SYSCALL_RETURN(&p->thread.regs, 0); if (sp != 0) REGS_SP(p->thread.regs.regs.gp) = sp; handler = fork_handler; arch_copy_thread(¤t->thread.arch, &p->thread.arch); } else { get_safe_registers(p->thread.regs.regs.gp, p->thread.regs.regs.fp); p->thread.request.u.thread.proc = args->fn; p->thread.request.u.thread.arg = args->fn_arg; handler = new_thread_handler; } new_thread(task_stack_page(p), &p->thread.switch_buf, handler); if (!args->fn) { clear_flushed_tls(p); /* * Set a new TLS for the child thread? */ if (clone_flags & CLONE_SETTLS) ret = arch_set_tls(p, tls); } return ret; } void initial_thread_cb(void (*proc)(void *), void *arg) { int save_kmalloc_ok = kmalloc_ok; kmalloc_ok = 0; initial_thread_cb_skas(proc, arg); kmalloc_ok = save_kmalloc_ok; } void um_idle_sleep(void) { if (time_travel_mode != TT_MODE_OFF) time_travel_sleep(); else os_idle_sleep(); } void arch_cpu_idle(void) { cpu_tasks[current_thread_info()->cpu].pid = os_getpid(); um_idle_sleep(); raw_local_irq_enable(); } int __cant_sleep(void) { return in_atomic() || irqs_disabled() || in_interrupt(); /* Is in_interrupt() really needed? */ } int user_context(unsigned long sp) { unsigned long stack; stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER); return stack != (unsigned long) current_thread_info(); } extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end; void do_uml_exitcalls(void) { exitcall_t *call; call = &__uml_exitcall_end; while (--call >= &__uml_exitcall_begin) (*call)(); } char *uml_strdup(const char *string) { return kstrdup(string, GFP_KERNEL); } EXPORT_SYMBOL(uml_strdup); int copy_to_user_proc(void __user *to, void *from, int size) { return copy_to_user(to, from, size); } int copy_from_user_proc(void *to, void __user *from, int size) { return copy_from_user(to, from, size); } int clear_user_proc(void __user *buf, int size) { return clear_user(buf, size); } static atomic_t using_sysemu = ATOMIC_INIT(0); int sysemu_supported; void set_using_sysemu(int value) { if (value > sysemu_supported) return; atomic_set(&using_sysemu, value); } int get_using_sysemu(void) { return atomic_read(&using_sysemu); } static int sysemu_proc_show(struct seq_file *m, void *v) { seq_printf(m, "%d\n", get_using_sysemu()); return 0; } static int sysemu_proc_open(struct inode *inode, struct file *file) { return single_open(file, sysemu_proc_show, NULL); } static ssize_t sysemu_proc_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) { char tmp[2]; if (copy_from_user(tmp, buf, 1)) return -EFAULT; if (tmp[0] >= '0' && tmp[0] <= '2') set_using_sysemu(tmp[0] - '0'); /* We use the first char, but pretend to write everything */ return count; } static const struct proc_ops sysemu_proc_ops = { .proc_open = sysemu_proc_open, .proc_read = seq_read, .proc_lseek = seq_lseek, .proc_release = single_release, .proc_write = sysemu_proc_write, }; int __init make_proc_sysemu(void) { struct proc_dir_entry *ent; if (!sysemu_supported) return 0; ent = proc_create("sysemu", 0600, NULL, &sysemu_proc_ops); if (ent == NULL) { printk(KERN_WARNING "Failed to register /proc/sysemu\n"); return 0; } return 0; } late_initcall(make_proc_sysemu); int singlestepping(void * t) { struct task_struct *task = t ? t : current; if (!test_thread_flag(TIF_SINGLESTEP)) return 0; if (task->thread.singlestep_syscall) return 1; return 2; } /* * Only x86 and x86_64 have an arch_align_stack(). * All other arches have "#define arch_align_stack(x) (x)" * in their asm/exec.h * As this is included in UML from asm-um/system-generic.h, * we can use it to behave as the subarch does. */ #ifndef arch_align_stack unsigned long arch_align_stack(unsigned long sp) { if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) sp -= prandom_u32_max(8192); return sp & ~0xf; } #endif unsigned long __get_wchan(struct task_struct *p) { unsigned long stack_page, sp, ip; bool seen_sched = 0; stack_page = (unsigned long) task_stack_page(p); /* Bail if the process has no kernel stack for some reason */ if (stack_page == 0) return 0; sp = p->thread.switch_buf->JB_SP; /* * Bail if the stack pointer is below the bottom of the kernel * stack for some reason */ if (sp < stack_page) return 0; while (sp < stack_page + THREAD_SIZE) { ip = *((unsigned long *) sp); if (in_sched_functions(ip)) /* Ignore everything until we're above the scheduler */ seen_sched = 1; else if (kernel_text_address(ip) && seen_sched) return ip; sp += sizeof(unsigned long); } return 0; } int elf_core_copy_fpregs(struct task_struct *t, elf_fpregset_t *fpu) { int cpu = current_thread_info()->cpu; return save_i387_registers(userspace_pid[cpu], (unsigned long *) fpu); } |