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 #include "um_malloc.h" 50 51 /* This is a per-cpu array. A processor only modifies its entry and it only 52 * cares about its entry, so it's OK if another processor is modifying its 53 * entry. 54 */ 55 struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } }; 56 57 static inline int external_pid(struct task_struct *task) 58 { 59 return CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task); 60 } 61 62 int pid_to_processor_id(int pid) 63 { 64 int i; 65 66 for(i = 0; i < ncpus; i++){ 67 if(cpu_tasks[i].pid == pid) 68 return i; 69 } 70 return -1; 71 } 72 73 void free_stack(unsigned long stack, int order) 74 { 75 free_pages(stack, order); 76 } 77 78 unsigned long alloc_stack(int order, int atomic) 79 { 80 unsigned long page; 81 gfp_t flags = GFP_KERNEL; 82 83 if (atomic) 84 flags = GFP_ATOMIC; 85 page = __get_free_pages(flags, order); 86 if(page == 0) 87 return 0; 88 stack_protections(page); 89 return page; 90 } 91 92 int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) 93 { 94 int pid; 95 96 current->thread.request.u.thread.proc = fn; 97 current->thread.request.u.thread.arg = arg; 98 pid = do_fork(CLONE_VM | CLONE_UNTRACED | flags, 0, 99 ¤t->thread.regs, 0, NULL, NULL); 100 return pid; 101 } 102 103 static inline void set_current(struct task_struct *task) 104 { 105 cpu_tasks[task_thread_info(task)->cpu] = ((struct cpu_task) 106 { external_pid(task), task }); 107 } 108 109 void *_switch_to(void *prev, void *next, void *last) 110 { 111 struct task_struct *from = prev; 112 struct task_struct *to= next; 113 114 to->thread.prev_sched = from; 115 set_current(to); 116 117 do { 118 current->thread.saved_task = NULL ; 119 CHOOSE_MODE_PROC(switch_to_tt, switch_to_skas, prev, next); 120 if(current->thread.saved_task) 121 show_regs(&(current->thread.regs)); 122 next= current->thread.saved_task; 123 prev= current; 124 } while(current->thread.saved_task); 125 126 return current->thread.prev_sched; 127 128 } 129 130 void interrupt_end(void) 131 { 132 if(need_resched()) 133 schedule(); 134 if(test_tsk_thread_flag(current, TIF_SIGPENDING)) 135 do_signal(); 136 } 137 138 void release_thread(struct task_struct *task) 139 { 140 CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task)); 141 } 142 143 void exit_thread(void) 144 { 145 unprotect_stack((unsigned long) current_thread); 146 } 147 148 void *get_current(void) 149 { 150 return current; 151 } 152 153 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, 154 unsigned long stack_top, struct task_struct * p, 155 struct pt_regs *regs) 156 { 157 int ret; 158 159 p->thread = (struct thread_struct) INIT_THREAD; 160 ret = CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr, 161 clone_flags, sp, stack_top, p, regs); 162 163 if (ret || !current->thread.forking) 164 goto out; 165 166 clear_flushed_tls(p); 167 168 /* 169 * Set a new TLS for the child thread? 170 */ 171 if (clone_flags & CLONE_SETTLS) 172 ret = arch_copy_tls(p); 173 174 out: 175 return ret; 176 } 177 178 void initial_thread_cb(void (*proc)(void *), void *arg) 179 { 180 int save_kmalloc_ok = kmalloc_ok; 181 182 kmalloc_ok = 0; 183 CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc, 184 arg); 185 kmalloc_ok = save_kmalloc_ok; 186 } 187 188 #ifdef CONFIG_MODE_TT 189 unsigned long stack_sp(unsigned long page) 190 { 191 return page + PAGE_SIZE - sizeof(void *); 192 } 193 #endif 194 195 void default_idle(void) 196 { 197 CHOOSE_MODE(uml_idle_timer(), (void) 0); 198 199 while(1){ 200 /* endless idle loop with no priority at all */ 201 202 /* 203 * although we are an idle CPU, we do not want to 204 * get into the scheduler unnecessarily. 205 */ 206 if(need_resched()) 207 schedule(); 208 209 idle_sleep(10); 210 } 211 } 212 213 void cpu_idle(void) 214 { 215 CHOOSE_MODE(init_idle_tt(), init_idle_skas()); 216 } 217 218 void *um_virt_to_phys(struct task_struct *task, unsigned long addr, 219 pte_t *pte_out) 220 { 221 pgd_t *pgd; 222 pud_t *pud; 223 pmd_t *pmd; 224 pte_t *pte; 225 pte_t ptent; 226 227 if(task->mm == NULL) 228 return ERR_PTR(-EINVAL); 229 pgd = pgd_offset(task->mm, addr); 230 if(!pgd_present(*pgd)) 231 return ERR_PTR(-EINVAL); 232 233 pud = pud_offset(pgd, addr); 234 if(!pud_present(*pud)) 235 return ERR_PTR(-EINVAL); 236 237 pmd = pmd_offset(pud, addr); 238 if(!pmd_present(*pmd)) 239 return ERR_PTR(-EINVAL); 240 241 pte = pte_offset_kernel(pmd, addr); 242 ptent = *pte; 243 if(!pte_present(ptent)) 244 return ERR_PTR(-EINVAL); 245 246 if(pte_out != NULL) 247 *pte_out = ptent; 248 return (void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK); 249 } 250 251 char *current_cmd(void) 252 { 253 #if defined(CONFIG_SMP) || defined(CONFIG_HIGHMEM) 254 return "(Unknown)"; 255 #else 256 void *addr = um_virt_to_phys(current, current->mm->arg_start, NULL); 257 return IS_ERR(addr) ? "(Unknown)": __va((unsigned long) addr); 258 #endif 259 } 260 261 void dump_thread(struct pt_regs *regs, struct user *u) 262 { 263 } 264 265 void *um_kmalloc(int size) 266 { 267 return kmalloc(size, GFP_KERNEL); 268 } 269 270 void *um_kmalloc_atomic(int size) 271 { 272 return kmalloc(size, GFP_ATOMIC); 273 } 274 275 void *um_vmalloc(int size) 276 { 277 return vmalloc(size); 278 } 279 280 int __cant_sleep(void) { 281 return in_atomic() || irqs_disabled() || in_interrupt(); 282 /* Is in_interrupt() really needed? */ 283 } 284 285 int user_context(unsigned long sp) 286 { 287 unsigned long stack; 288 289 stack = sp & (PAGE_MASK << CONFIG_KERNEL_STACK_ORDER); 290 return stack != (unsigned long) current_thread; 291 } 292 293 extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end; 294 295 void do_uml_exitcalls(void) 296 { 297 exitcall_t *call; 298 299 call = &__uml_exitcall_end; 300 while (--call >= &__uml_exitcall_begin) 301 (*call)(); 302 } 303 304 char *uml_strdup(char *string) 305 { 306 return kstrdup(string, GFP_KERNEL); 307 } 308 309 int copy_to_user_proc(void __user *to, void *from, int size) 310 { 311 return copy_to_user(to, from, size); 312 } 313 314 int copy_from_user_proc(void *to, void __user *from, int size) 315 { 316 return copy_from_user(to, from, size); 317 } 318 319 int clear_user_proc(void __user *buf, int size) 320 { 321 return clear_user(buf, size); 322 } 323 324 int strlen_user_proc(char __user *str) 325 { 326 return strlen_user(str); 327 } 328 329 int smp_sigio_handler(void) 330 { 331 #ifdef CONFIG_SMP 332 int cpu = current_thread->cpu; 333 IPI_handler(cpu); 334 if(cpu != 0) 335 return 1; 336 #endif 337 return 0; 338 } 339 340 int cpu(void) 341 { 342 return current_thread->cpu; 343 } 344 345 static atomic_t using_sysemu = ATOMIC_INIT(0); 346 int sysemu_supported; 347 348 void set_using_sysemu(int value) 349 { 350 if (value > sysemu_supported) 351 return; 352 atomic_set(&using_sysemu, value); 353 } 354 355 int get_using_sysemu(void) 356 { 357 return atomic_read(&using_sysemu); 358 } 359 360 static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data) 361 { 362 if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/ 363 *eof = 1; 364 365 return strlen(buf); 366 } 367 368 static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned long count,void *data) 369 { 370 char tmp[2]; 371 372 if (copy_from_user(tmp, buf, 1)) 373 return -EFAULT; 374 375 if (tmp[0] >= '0' && tmp[0] <= '2') 376 set_using_sysemu(tmp[0] - '0'); 377 return count; /*We use the first char, but pretend to write everything*/ 378 } 379 380 int __init make_proc_sysemu(void) 381 { 382 struct proc_dir_entry *ent; 383 if (!sysemu_supported) 384 return 0; 385 386 ent = create_proc_entry("sysemu", 0600, &proc_root); 387 388 if (ent == NULL) 389 { 390 printk(KERN_WARNING "Failed to register /proc/sysemu\n"); 391 return 0; 392 } 393 394 ent->read_proc = proc_read_sysemu; 395 ent->write_proc = proc_write_sysemu; 396 397 return 0; 398 } 399 400 late_initcall(make_proc_sysemu); 401 402 int singlestepping(void * t) 403 { 404 struct task_struct *task = t ? t : current; 405 406 if ( ! (task->ptrace & PT_DTRACE) ) 407 return(0); 408 409 if (task->thread.singlestep_syscall) 410 return(1); 411 412 return 2; 413 } 414 415 /* 416 * Only x86 and x86_64 have an arch_align_stack(). 417 * All other arches have "#define arch_align_stack(x) (x)" 418 * in their asm/system.h 419 * As this is included in UML from asm-um/system-generic.h, 420 * we can use it to behave as the subarch does. 421 */ 422 #ifndef arch_align_stack 423 unsigned long arch_align_stack(unsigned long sp) 424 { 425 if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) 426 sp -= get_random_int() % 8192; 427 return sp & ~0xf; 428 } 429 #endif 430