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 */ 55struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } }; 56 57static inline int external_pid(struct task_struct *task) 58{ 59 return CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task); 60} 61 62int 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 73void free_stack(unsigned long stack, int order) 74{ 75 free_pages(stack, order); 76} 77 78unsigned 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 92int 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 103static 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 109void *_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 130void interrupt_end(void) 131{ 132 if(need_resched()) 133 schedule(); 134 if(test_tsk_thread_flag(current, TIF_SIGPENDING)) 135 do_signal(); 136} 137 138void release_thread(struct task_struct *task) 139{ 140 CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task)); 141} 142 143void exit_thread(void) 144{ 145 unprotect_stack((unsigned long) current_thread); 146} 147 148void *get_current(void) 149{ 150 return current; 151} 152 153int 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 174out: 175 return ret; 176} 177 178void 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 189unsigned long stack_sp(unsigned long page) 190{ 191 return page + PAGE_SIZE - sizeof(void *); 192} 193#endif 194 195void 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 213void cpu_idle(void) 214{ 215 CHOOSE_MODE(init_idle_tt(), init_idle_skas()); 216} 217 218void *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 251char *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 261void dump_thread(struct pt_regs *regs, struct user *u) 262{ 263} 264 265void *um_kmalloc(int size) 266{ 267 return kmalloc(size, GFP_KERNEL); 268} 269 270void *um_kmalloc_atomic(int size) 271{ 272 return kmalloc(size, GFP_ATOMIC); 273} 274 275void *um_vmalloc(int size) 276{ 277 return vmalloc(size); 278} 279 280int __cant_sleep(void) { 281 return in_atomic() || irqs_disabled() || in_interrupt(); 282 /* Is in_interrupt() really needed? */ 283} 284 285int 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 293extern exitcall_t __uml_exitcall_begin, __uml_exitcall_end; 294 295void 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 304char *uml_strdup(char *string) 305{ 306 return kstrdup(string, GFP_KERNEL); 307} 308 309int copy_to_user_proc(void __user *to, void *from, int size) 310{ 311 return copy_to_user(to, from, size); 312} 313 314int copy_from_user_proc(void *to, void __user *from, int size) 315{ 316 return copy_from_user(to, from, size); 317} 318 319int clear_user_proc(void __user *buf, int size) 320{ 321 return clear_user(buf, size); 322} 323 324int strlen_user_proc(char __user *str) 325{ 326 return strlen_user(str); 327} 328 329int 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 340int cpu(void) 341{ 342 return current_thread->cpu; 343} 344 345static atomic_t using_sysemu = ATOMIC_INIT(0); 346int sysemu_supported; 347 348void set_using_sysemu(int value) 349{ 350 if (value > sysemu_supported) 351 return; 352 atomic_set(&using_sysemu, value); 353} 354 355int get_using_sysemu(void) 356{ 357 return atomic_read(&using_sysemu); 358} 359 360static 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 368static 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 380int __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 400late_initcall(make_proc_sysemu); 401 402int 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 423unsigned 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