1 /* 2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) 3 * Copyright 2003 PathScale, Inc. 4 * Licensed under the GPL 5 */ 6 7 #include "linux/kernel.h" 8 #include "linux/sched.h" 9 #include "linux/interrupt.h" 10 #include "linux/string.h" 11 #include "linux/mm.h" 12 #include "linux/slab.h" 13 #include "linux/utsname.h" 14 #include "linux/fs.h" 15 #include "linux/utime.h" 16 #include "linux/smp_lock.h" 17 #include "linux/module.h" 18 #include "linux/init.h" 19 #include "linux/capability.h" 20 #include "linux/vmalloc.h" 21 #include "linux/spinlock.h" 22 #include "linux/proc_fs.h" 23 #include "linux/ptrace.h" 24 #include "linux/random.h" 25 #include "linux/personality.h" 26 #include "asm/unistd.h" 27 #include "asm/mman.h" 28 #include "asm/segment.h" 29 #include "asm/stat.h" 30 #include "asm/pgtable.h" 31 #include "asm/processor.h" 32 #include "asm/tlbflush.h" 33 #include "asm/uaccess.h" 34 #include "asm/user.h" 35 #include "kern_util.h" 36 #include "as-layout.h" 37 #include "kern.h" 38 #include "signal_kern.h" 39 #include "init.h" 40 #include "irq_user.h" 41 #include "mem_user.h" 42 #include "tlb.h" 43 #include "frame_kern.h" 44 #include "sigcontext.h" 45 #include "os.h" 46 #include "mode.h" 47 #include "mode_kern.h" 48 #include "choose-mode.h" 49 50 /* This is a per-cpu array. A processor only modifies its entry and it only 51 * cares about its entry, so it's OK if another processor is modifying its 52 * entry. 53 */ 54 struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } }; 55 56 static inline int external_pid(struct task_struct *task) 57 { 58 return CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task); 59 } 60 61 int pid_to_processor_id(int pid) 62 { 63 int i; 64 65 for(i = 0; i < ncpus; i++){ 66 if(cpu_tasks[i].pid == pid) 67 return i; 68 } 69 return -1; 70 } 71 72 void free_stack(unsigned long stack, int order) 73 { 74 free_pages(stack, order); 75 } 76 77 unsigned long alloc_stack(int order, int atomic) 78 { 79 unsigned long page; 80 gfp_t flags = GFP_KERNEL; 81 82 if (atomic) 83 flags = GFP_ATOMIC; 84 page = __get_free_pages(flags, order); 85 if (page == 0) 86 return 0; 87 88 return page; 89 } 90 91 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) 92 { 93 int pid; 94 95 current->thread.request.u.thread.proc = fn; 96 current->thread.request.u.thread.arg = arg; 97 pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, 98 ¤t->thread.regs, 0, NULL, NULL); 99 return pid; 100 } 101 102 static inline void set_current(struct task_struct *task) 103 { 104 cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task) 105 { external_pid(task), task }); 106 } 107 108 void *_switch_to(void *prev, void *next, void *last) 109 { 110 struct task_struct *from = prev; 111 struct task_struct *to= next; 112 113 to->thread.prev_sched = from; 114 set_current(to); 115 116 do { 117 current->thread.saved_task = NULL ; 118 CHOOSE_MODE_PROC(switch_to_tt, switch_to_skas, prev, next); 119 if(current->thread.saved_task) 120 show_regs(&(current->thread.regs)); 121 next= current->thread.saved_task; 122 prev= current; 123 } while(current->thread.saved_task); 124 125 return current->thread.prev_sched; 126 127 } 128 129 void interrupt_end(void) 130 { 131 if(need_resched()) 132 schedule(); 133 if(test_tsk_thread_flag(current, TIF_SIGPENDING)) 134 do_signal(); 135 } 136 137 void release_thread(struct task_struct *task) 138 { 139 CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task)); 140 } 141 142 void exit_thread(void) 143 { 144 } 145 146 void *get_current(void) 147 { 148 return current; 149 } 150 151 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, 152 unsigned long stack_top, struct task_struct * p, 153 struct pt_regs *regs) 154 { 155 int ret; 156 157 p->thread = (struct thread_struct) INIT_THREAD; 158 ret = CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr, 159 clone_flags, sp, stack_top, p, regs); 160 161 if (ret || !current->thread.forking) 162 goto out; 163 164 clear_flushed_tls(p); 165 166 /* 167 * Set a new TLS for the child thread? 168 */ 169 if (clone_flags & CLONE_SETTLS) 170 ret = arch_copy_tls(p); 171 172 out: 173 return ret; 174 } 175 176 void initial_thread_cb(void (*proc)(void *), void *arg) 177 { 178 int save_kmalloc_ok = kmalloc_ok; 179 180 kmalloc_ok = 0; 181 CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc, 182 arg); 183 kmalloc_ok = save_kmalloc_ok; 184 } 185 186 void default_idle(void) 187 { 188 CHOOSE_MODE(uml_idle_timer(), (void) 0); 189 190 while(1){ 191 /* endless idle loop with no priority at all */ 192 193 /* 194 * although we are an idle CPU, we do not want to 195 * get into the scheduler unnecessarily. 196 */ 197 if(need_resched()) 198 schedule(); 199 200 idle_sleep(10); 201 } 202 } 203 204 void cpu_idle(void) 205 { 206 CHOOSE_MODE(init_idle_tt(), init_idle_skas()); 207 } 208 209 void *um_virt_to_phys(struct task_struct *task, unsigned long addr, 210 pte_t *pte_out) 211 { 212 pgd_t *pgd; 213 pud_t *pud; 214 pmd_t *pmd; 215 pte_t *pte; 216 pte_t ptent; 217 218 if(task->mm == NULL) 219 return ERR_PTR(-EINVAL); 220 pgd = pgd_offset(task->mm, addr); 221 if(!pgd_present(*pgd)) 222 return ERR_PTR(-EINVAL); 223 224 pud = pud_offset(pgd, addr); 225 if(!pud_present(*pud)) 226 return ERR_PTR(-EINVAL); 227 228 pmd = pmd_offset(pud, addr); 229 if(!pmd_present(*pmd)) 230 return ERR_PTR(-EINVAL); 231 232 pte = pte_offset_kernel(pmd, addr); 233 ptent = *pte; 234 if(!pte_present(ptent)) 235 return ERR_PTR(-EINVAL); 236 237 if(pte_out != NULL) 238 *pte_out = ptent; 239 return (void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK); 240 } 241 242 char *current_cmd(void) 243 { 244 #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM) 245 return "(Unknown)"; 246 #else 247 void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL); 248 return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr); 249 #endif 250 } 251 252 void dump_thread(struct pt_regs *regs, struct user *u) 253 { 254 } 255 256 int __cant_sleep(void) { 257 return in_atomic() || irqs_disabled() || in_interrupt(); 258 /* Is in_interrupt() really needed? */ 259 } 260 261 int user_context(unsigned long sp) 262 { 263 unsigned long stack; 264 265 stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER); 266 return stack != (unsigned long) current_thread; 267 } 268 269 extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end; 270 271 void do_uml_exitcalls(void) 272 { 273 exitcall_t *call; 274 275 call = &__uml_exitcall_end; 276 while (--call >= &__uml_exitcall_begin) 277 (*call)(); 278 } 279 280 char *uml_strdup(char *string) 281 { 282 return kstrdup(string, GFP_KERNEL); 283 } 284 285 int copy_to_user_proc(void __user *to, void *from, int size) 286 { 287 return copy_to_user(to, from, size); 288 } 289 290 int copy_from_user_proc(void *to, void __user *from, int size) 291 { 292 return copy_from_user(to, from, size); 293 } 294 295 int clear_user_proc(void __user *buf, int size) 296 { 297 return clear_user(buf, size); 298 } 299 300 int strlen_user_proc(char __user *str) 301 { 302 return strlen_user(str); 303 } 304 305 int smp_sigio_handler(void) 306 { 307 #ifdef CONFIG_SMP 308 int cpu = current_thread->cpu; 309 IPI_handler(cpu); 310 if(cpu != 0) 311 return 1; 312 #endif 313 return 0; 314 } 315 316 int cpu(void) 317 { 318 return current_thread->cpu; 319 } 320 321 static atomic_t using_sysemu = ATOMIC_INIT(0); 322 int sysemu_supported; 323 324 void set_using_sysemu(int value) 325 { 326 if (value > sysemu_supported) 327 return; 328 atomic_set(&using_sysemu, value); 329 } 330 331 int get_using_sysemu(void) 332 { 333 return atomic_read(&using_sysemu); 334 } 335 336 static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data) 337 { 338 if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/ 339 *eof = 1; 340 341 return strlen(buf); 342 } 343 344 static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned long count,void *data) 345 { 346 char tmp[2]; 347 348 if (copy_from_user(tmp, buf, 1)) 349 return -EFAULT; 350 351 if (tmp[0] >= '0' && tmp[0] <= '2') 352 set_using_sysemu(tmp[0] - '0'); 353 return count; /*We use the first char, but pretend to write everything*/ 354 } 355 356 int __init make_proc_sysemu(void) 357 { 358 struct proc_dir_entry *ent; 359 if (!sysemu_supported) 360 return 0; 361 362 ent = create_proc_entry("sysemu", 0600, &proc_root); 363 364 if (ent == NULL) 365 { 366 printk(KERN_WARNING "Failed to register /proc/sysemu\n"); 367 return 0; 368 } 369 370 ent->read_proc = proc_read_sysemu; 371 ent->write_proc = proc_write_sysemu; 372 373 return 0; 374 } 375 376 late_initcall(make_proc_sysemu); 377 378 int singlestepping(void * t) 379 { 380 struct task_struct *task = t ? t : current; 381 382 if ( ! (task->ptrace & PT_DTRACE) ) 383 return(0); 384 385 if (task->thread.singlestep_syscall) 386 return(1); 387 388 return 2; 389 } 390 391 /* 392 * Only x86 and x86_64 have an arch_align_stack(). 393 * All other arches have "#define arch_align_stack(x) (x)" 394 * in their asm/system.h 395 * As this is included in UML from asm-um/system-generic.h, 396 * we can use it to behave as the subarch does. 397 */ 398 #ifndef arch_align_stack 399 unsigned long arch_align_stack(unsigned long sp) 400 { 401 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) 402 sp -= get_random_int() % 8192; 403 return sp & ~0xf; 404 } 405 #endif 406