1/* 2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com) 3 * Licensed under the GPL 4 */ 5 6#include <linux/compiler.h> 7#include "linux/sched.h" 8#include "linux/mm.h" 9#include "asm/elf.h" 10#include "asm/ptrace.h" 11#include "asm/uaccess.h" 12#include "asm/unistd.h" 13#include "sysdep/ptrace.h" 14#include "sysdep/sigcontext.h" 15#include "sysdep/sc.h" 16 17void arch_switch_to_tt(struct task_struct *from, struct task_struct *to) 18{ 19 update_debugregs(to->thread.arch.debugregs_seq); 20 arch_switch_tls_tt(from, to); 21} 22 23void arch_switch_to_skas(struct task_struct *from, struct task_struct *to) 24{ 25 int err = arch_switch_tls_skas(from, to); 26 if (!err) 27 return; 28 29 if (err != -EINVAL) 30 printk(KERN_WARNING "arch_switch_tls_skas failed, errno %d, not EINVAL\n", -err); 31 else 32 printk(KERN_WARNING "arch_switch_tls_skas failed, errno = EINVAL\n"); 33} 34 35int is_syscall(unsigned long addr) 36{ 37 unsigned short instr; 38 int n; 39 40 n = copy_from_user(&instr, (void __user *) addr, sizeof(instr)); 41 if(n){ 42 /* access_process_vm() grants access to vsyscall and stub, 43 * while copy_from_user doesn't. Maybe access_process_vm is 44 * slow, but that doesn't matter, since it will be called only 45 * in case of singlestepping, if copy_from_user failed. 46 */ 47 n = access_process_vm(current, addr, &instr, sizeof(instr), 0); 48 if(n != sizeof(instr)) { 49 printk("is_syscall : failed to read instruction from " 50 "0x%lx\n", addr); 51 return(1); 52 } 53 } 54 /* int 0x80 or sysenter */ 55 return((instr == 0x80cd) || (instr == 0x340f)); 56} 57 58/* determines which flags the user has access to. */ 59/* 1 = access 0 = no access */ 60#define FLAG_MASK 0x00044dd5 61 62int putreg(struct task_struct *child, int regno, unsigned long value) 63{ 64 regno >>= 2; 65 switch (regno) { 66 case FS: 67 if (value && (value & 3) != 3) 68 return -EIO; 69 PT_REGS_FS(&child->thread.regs) = value; 70 return 0; 71 case GS: 72 if (value && (value & 3) != 3) 73 return -EIO; 74 PT_REGS_GS(&child->thread.regs) = value; 75 return 0; 76 case DS: 77 case ES: 78 if (value && (value & 3) != 3) 79 return -EIO; 80 value &= 0xffff; 81 break; 82 case SS: 83 case CS: 84 if ((value & 3) != 3) 85 return -EIO; 86 value &= 0xffff; 87 break; 88 case EFL: 89 value &= FLAG_MASK; 90 value |= PT_REGS_EFLAGS(&child->thread.regs); 91 break; 92 } 93 PT_REGS_SET(&child->thread.regs, regno, value); 94 return 0; 95} 96 97int poke_user(struct task_struct *child, long addr, long data) 98{ 99 if ((addr & 3) || addr < 0) 100 return -EIO; 101 102 if (addr < MAX_REG_OFFSET) 103 return putreg(child, addr, data); 104 105 else if((addr >= offsetof(struct user, u_debugreg[0])) && 106 (addr <= offsetof(struct user, u_debugreg[7]))){ 107 addr -= offsetof(struct user, u_debugreg[0]); 108 addr = addr >> 2; 109 if((addr == 4) || (addr == 5)) return -EIO; 110 child->thread.arch.debugregs[addr] = data; 111 return 0; 112 } 113 return -EIO; 114} 115 116unsigned long getreg(struct task_struct *child, int regno) 117{ 118 unsigned long retval = ~0UL; 119 120 regno >>= 2; 121 switch (regno) { 122 case FS: 123 case GS: 124 case DS: 125 case ES: 126 case SS: 127 case CS: 128 retval = 0xffff; 129 /* fall through */ 130 default: 131 retval &= PT_REG(&child->thread.regs, regno); 132 } 133 return retval; 134} 135 136int peek_user(struct task_struct *child, long addr, long data) 137{ 138/* read the word at location addr in the USER area. */ 139 unsigned long tmp; 140 141 if ((addr & 3) || addr < 0) 142 return -EIO; 143 144 tmp = 0; /* Default return condition */ 145 if(addr < MAX_REG_OFFSET){ 146 tmp = getreg(child, addr); 147 } 148 else if((addr >= offsetof(struct user, u_debugreg[0])) && 149 (addr <= offsetof(struct user, u_debugreg[7]))){ 150 addr -= offsetof(struct user, u_debugreg[0]); 151 addr = addr >> 2; 152 tmp = child->thread.arch.debugregs[addr]; 153 } 154 return put_user(tmp, (unsigned long __user *) data); 155} 156 157struct i387_fxsave_struct { 158 unsigned short cwd; 159 unsigned short swd; 160 unsigned short twd; 161 unsigned short fop; 162 long fip; 163 long fcs; 164 long foo; 165 long fos; 166 long mxcsr; 167 long reserved; 168 long st_space[32]; /* 8*16 bytes for each FP-reg = 128 bytes */ 169 long xmm_space[32]; /* 8*16 bytes for each XMM-reg = 128 bytes */ 170 long padding[56]; 171}; 172 173/* 174 * FPU tag word conversions. 175 */ 176 177static inline unsigned short twd_i387_to_fxsr( unsigned short twd ) 178{ 179 unsigned int tmp; /* to avoid 16 bit prefixes in the code */ 180 181 /* Transform each pair of bits into 01 (valid) or 00 (empty) */ 182 tmp = ~twd; 183 tmp = (tmp | (tmp>>1)) & 0x5555; /* 0V0V0V0V0V0V0V0V */ 184 /* and move the valid bits to the lower byte. */ 185 tmp = (tmp | (tmp >> 1)) & 0x3333; /* 00VV00VV00VV00VV */ 186 tmp = (tmp | (tmp >> 2)) & 0x0f0f; /* 0000VVVV0000VVVV */ 187 tmp = (tmp | (tmp >> 4)) & 0x00ff; /* 00000000VVVVVVVV */ 188 return tmp; 189} 190 191static inline unsigned long twd_fxsr_to_i387( struct i387_fxsave_struct *fxsave ) 192{ 193 struct _fpxreg *st = NULL; 194 unsigned long twd = (unsigned long) fxsave->twd; 195 unsigned long tag; 196 unsigned long ret = 0xffff0000; 197 int i; 198 199#define FPREG_ADDR(f, n) ((char *)&(f)->st_space + (n) * 16); 200 201 for ( i = 0 ; i < 8 ; i++ ) { 202 if ( twd & 0x1 ) { 203 st = (struct _fpxreg *) FPREG_ADDR( fxsave, i ); 204 205 switch ( st->exponent & 0x7fff ) { 206 case 0x7fff: 207 tag = 2; /* Special */ 208 break; 209 case 0x0000: 210 if ( !st->significand[0] && 211 !st->significand[1] && 212 !st->significand[2] && 213 !st->significand[3] ) { 214 tag = 1; /* Zero */ 215 } else { 216 tag = 2; /* Special */ 217 } 218 break; 219 default: 220 if ( st->significand[3] & 0x8000 ) { 221 tag = 0; /* Valid */ 222 } else { 223 tag = 2; /* Special */ 224 } 225 break; 226 } 227 } else { 228 tag = 3; /* Empty */ 229 } 230 ret |= (tag << (2 * i)); 231 twd = twd >> 1; 232 } 233 return ret; 234} 235 236/* 237 * FXSR floating point environment conversions. 238 */ 239 240#ifdef CONFIG_MODE_TT 241static inline int convert_fxsr_to_user_tt(struct _fpstate __user *buf, 242 struct pt_regs *regs) 243{ 244 struct i387_fxsave_struct *fxsave = SC_FXSR_ENV(PT_REGS_SC(regs)); 245 unsigned long env[7]; 246 struct _fpreg __user *to; 247 struct _fpxreg *from; 248 int i; 249 250 env[0] = (unsigned long)fxsave->cwd | 0xffff0000; 251 env[1] = (unsigned long)fxsave->swd | 0xffff0000; 252 env[2] = twd_fxsr_to_i387(fxsave); 253 env[3] = fxsave->fip; 254 env[4] = fxsave->fcs | ((unsigned long)fxsave->fop << 16); 255 env[5] = fxsave->foo; 256 env[6] = fxsave->fos; 257 258 if ( __copy_to_user( buf, env, 7 * sizeof(unsigned long) ) ) 259 return 1; 260 261 to = &buf->_st[0]; 262 from = (struct _fpxreg *) &fxsave->st_space[0]; 263 for ( i = 0 ; i < 8 ; i++, to++, from++ ) { 264 if ( __copy_to_user( to, from, sizeof(*to) ) ) 265 return 1; 266 } 267 return 0; 268} 269#endif 270 271static inline int convert_fxsr_to_user(struct _fpstate __user *buf, 272 struct pt_regs *regs) 273{ 274 return(CHOOSE_MODE(convert_fxsr_to_user_tt(buf, regs), 0)); 275} 276 277#ifdef CONFIG_MODE_TT 278static inline int convert_fxsr_from_user_tt(struct pt_regs *regs, 279 struct _fpstate __user *buf) 280{ 281 struct i387_fxsave_struct *fxsave = SC_FXSR_ENV(PT_REGS_SC(regs)); 282 unsigned long env[7]; 283 struct _fpxreg *to; 284 struct _fpreg __user *from; 285 int i; 286 287 if ( __copy_from_user( env, buf, 7 * sizeof(long) ) ) 288 return 1; 289 290 fxsave->cwd = (unsigned short)(env[0] & 0xffff); 291 fxsave->swd = (unsigned short)(env[1] & 0xffff); 292 fxsave->twd = twd_i387_to_fxsr((unsigned short)(env[2] & 0xffff)); 293 fxsave->fip = env[3]; 294 fxsave->fop = (unsigned short)((env[4] & 0xffff0000) >> 16); 295 fxsave->fcs = (env[4] & 0xffff); 296 fxsave->foo = env[5]; 297 fxsave->fos = env[6]; 298 299 to = (struct _fpxreg *) &fxsave->st_space[0]; 300 from = &buf->_st[0]; 301 for ( i = 0 ; i < 8 ; i++, to++, from++ ) { 302 if ( __copy_from_user( to, from, sizeof(*from) ) ) 303 return 1; 304 } 305 return 0; 306} 307#endif 308 309static inline int convert_fxsr_from_user(struct pt_regs *regs, 310 struct _fpstate __user *buf) 311{ 312 return(CHOOSE_MODE(convert_fxsr_from_user_tt(regs, buf), 0)); 313} 314 315int get_fpregs(unsigned long buf, struct task_struct *child) 316{ 317 int err; 318 319 err = convert_fxsr_to_user((struct _fpstate __user *) buf, 320 &child->thread.regs); 321 if(err) return(-EFAULT); 322 else return(0); 323} 324 325int set_fpregs(unsigned long buf, struct task_struct *child) 326{ 327 int err; 328 329 err = convert_fxsr_from_user(&child->thread.regs, 330 (struct _fpstate __user *) buf); 331 if(err) return(-EFAULT); 332 else return(0); 333} 334 335#ifdef CONFIG_MODE_TT 336int get_fpxregs_tt(unsigned long buf, struct task_struct *tsk) 337{ 338 struct pt_regs *regs = &tsk->thread.regs; 339 struct i387_fxsave_struct *fxsave = SC_FXSR_ENV(PT_REGS_SC(regs)); 340 int err; 341 342 err = __copy_to_user((void __user *) buf, fxsave, 343 sizeof(struct user_fxsr_struct)); 344 if(err) return -EFAULT; 345 else return 0; 346} 347#endif 348 349int get_fpxregs(unsigned long buf, struct task_struct *tsk) 350{ 351 return(CHOOSE_MODE(get_fpxregs_tt(buf, tsk), 0)); 352} 353 354#ifdef CONFIG_MODE_TT 355int set_fpxregs_tt(unsigned long buf, struct task_struct *tsk) 356{ 357 struct pt_regs *regs = &tsk->thread.regs; 358 struct i387_fxsave_struct *fxsave = SC_FXSR_ENV(PT_REGS_SC(regs)); 359 int err; 360 361 err = __copy_from_user(fxsave, (void __user *) buf, 362 sizeof(struct user_fxsr_struct) ); 363 if(err) return -EFAULT; 364 else return 0; 365} 366#endif 367 368int set_fpxregs(unsigned long buf, struct task_struct *tsk) 369{ 370 return(CHOOSE_MODE(set_fpxregs_tt(buf, tsk), 0)); 371} 372 373#ifdef notdef 374int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) 375{ 376 fpu->cwd = (((SC_FP_CW(PT_REGS_SC(regs)) & 0xffff) << 16) | 377 (SC_FP_SW(PT_REGS_SC(regs)) & 0xffff)); 378 fpu->swd = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff; 379 fpu->twd = SC_FP_IPOFF(PT_REGS_SC(regs)); 380 fpu->fip = SC_FP_CSSEL(PT_REGS_SC(regs)) & 0xffff; 381 fpu->fcs = SC_FP_DATAOFF(PT_REGS_SC(regs)); 382 fpu->foo = SC_FP_DATASEL(PT_REGS_SC(regs)); 383 fpu->fos = 0; 384 memcpy(fpu->st_space, (void *) SC_FP_ST(PT_REGS_SC(regs)), 385 sizeof(fpu->st_space)); 386 return(1); 387} 388#endif 389 390#ifdef CONFIG_MODE_TT 391static inline void copy_fpu_fxsave_tt(struct pt_regs *regs, 392 struct user_i387_struct *buf) 393{ 394 struct i387_fxsave_struct *fpu = SC_FXSR_ENV(PT_REGS_SC(regs)); 395 unsigned short *to; 396 unsigned short *from; 397 int i; 398 399 memcpy( buf, fpu, 7 * sizeof(long) ); 400 401 to = (unsigned short *) &buf->st_space[0]; 402 from = (unsigned short *) &fpu->st_space[0]; 403 for ( i = 0 ; i < 8 ; i++, to += 5, from += 8 ) { 404 memcpy( to, from, 5 * sizeof(unsigned short) ); 405 } 406} 407#endif 408 409static inline void copy_fpu_fxsave(struct pt_regs *regs, 410 struct user_i387_struct *buf) 411{ 412 (void) CHOOSE_MODE(copy_fpu_fxsave_tt(regs, buf), 0); 413} 414 415int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu ) 416{ 417 copy_fpu_fxsave(regs, (struct user_i387_struct *) fpu); 418 return(1); 419} 420 421/* 422 * Overrides for Emacs so that we follow Linus's tabbing style. 423 * Emacs will notice this stuff at the end of the file and automatically 424 * adjust the settings for this buffer only. This must remain at the end 425 * of the file. 426 * --------------------------------------------------------------------------- 427 * Local variables: 428 * c-file-style: "linux" 429 * End: 430 */ 431