arch/mips/kernel/ptrace32.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1992 Ross Biro
   7  * Copyright (C) Linus Torvalds
   8  * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
   9  * Copyright (C) 1996 David S. Miller
  10  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
  11  * Copyright (C) 1999 MIPS Technologies, Inc.
  12  * Copyright (C) 2000 Ulf Carlsson
  13  *
  14  * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
  15  * binaries.
  16  */
  17 #include <linux/compiler.h>
  18 #include <linux/compat.h>
  19 #include <linux/kernel.h>
  20 #include <linux/sched.h>
  21 #include <linux/mm.h>
  22 #include <linux/errno.h>
  23 #include <linux/ptrace.h>
  24 #include <linux/smp.h>
  25 #include <linux/user.h>
  26 #include <linux/security.h>
  27
  28 #include <asm/cpu.h>
  29 #include <asm/dsp.h>
  30 #include <asm/fpu.h>
  31 #include <asm/mipsregs.h>
  32 #include <asm/mipsmtregs.h>
  33 #include <asm/pgtable.h>
  34 #include <asm/page.h>
  35 #include <asm/uaccess.h>
  36 #include <asm/bootinfo.h>
  37
  38 /*
  39  * Tracing a 32-bit process with a 64-bit strace and vice versa will not
  40  * work.  I don't know how to fix this.
  41  */
  42 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
  43                         compat_ulong_t caddr, compat_ulong_t cdata)
  44 {
  45         int addr = caddr;
  46         int data = cdata;
  47         int ret;
  48
  49         switch (request) {
  50
  51         /*
  52          * Read 4 bytes of the other process' storage
  53          *  data is a pointer specifying where the user wants the
  54          *      4 bytes copied into
  55          *  addr is a pointer in the user's storage that contains an 8 byte
  56          *      address in the other process of the 4 bytes that is to be read
  57          * (this is run in a 32-bit process looking at a 64-bit process)
  58          * when I and D space are separate, these will need to be fixed.
  59          */
  60         case PTRACE_PEEKTEXT_3264:
  61         case PTRACE_PEEKDATA_3264: {
  62                 u32 tmp;
  63                 int copied;
  64                 u32 __user * addrOthers;
  65
  66                 ret = -EIO;
  67
  68                 /* Get the addr in the other process that we want to read */
  69                 if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
  70                         break;
  71
  72                 copied = access_process_vm(child, (u64)addrOthers, &tmp,
  73                                 sizeof(tmp), 0);
  74                 if (copied != sizeof(tmp))
  75                         break;
  76                 ret = put_user(tmp, (u32 __user *) (unsigned long) data);
  77                 break;
  78         }
  79
  80         /* Read the word at location addr in the USER area. */
  81         case PTRACE_PEEKUSR: {
  82                 struct pt_regs *regs;
  83                 unsigned int tmp;
  84
  85                 regs = task_pt_regs(child);
  86                 ret = 0;  /* Default return value. */
  87
  88                 switch (addr) {
  89                 case 0 ... 31:
  90                         tmp = regs->regs[addr];
  91                         break;
  92                 case FPR_BASE ... FPR_BASE + 31:
  93                         if (tsk_used_math(child)) {
  94                                 fpureg_t *fregs = get_fpu_regs(child);
  95
  96                                 /*
  97                                  * The odd registers are actually the high
  98                                  * order bits of the values stored in the even
  99                                  * registers - unless we're using r2k_switch.S.
 100                                  */
 101                                 if (addr & 1)
 102                                         tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32);
 103                                 else
 104                                         tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff);
 105                         } else {
 106                                 tmp = -1;       /* FP not yet used  */
 107                         }
 108                         break;
 109                 case PC:
 110                         tmp = regs->cp0_epc;
 111                         break;
 112                 case CAUSE:
 113                         tmp = regs->cp0_cause;
 114                         break;
 115                 case BADVADDR:
 116                         tmp = regs->cp0_badvaddr;
 117                         break;
 118                 case MMHI:
 119                         tmp = regs->hi;
 120                         break;
 121                 case MMLO:
 122                         tmp = regs->lo;
 123                         break;
 124                 case FPC_CSR:
 125                         tmp = child->thread.fpu.fcr31;
 126                         break;
 127                 case FPC_EIR: { /* implementation / version register */
 128                         unsigned int flags;
 129 #ifdef CONFIG_MIPS_MT_SMTC
 130                         unsigned int irqflags;
 131                         unsigned int mtflags;
 132 #endif /* CONFIG_MIPS_MT_SMTC */
 133
 134                         preempt_disable();
 135                         if (!cpu_has_fpu) {
 136                                 preempt_enable();
 137                                 tmp = 0;
 138                                 break;
 139                         }
 140
 141 #ifdef CONFIG_MIPS_MT_SMTC
 142                         /* Read-modify-write of Status must be atomic */
 143                         local_irq_save(irqflags);
 144                         mtflags = dmt();
 145 #endif /* CONFIG_MIPS_MT_SMTC */
 146
 147                         if (cpu_has_mipsmt) {
 148                                 unsigned int vpflags = dvpe();
 149                                 flags = read_c0_status();
 150                                 __enable_fpu();
 151                                 __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
 152                                 write_c0_status(flags);
 153                                 evpe(vpflags);
 154                         } else {
 155                                 flags = read_c0_status();
 156                                 __enable_fpu();
 157                                 __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
 158                                 write_c0_status(flags);
 159                         }
 160 #ifdef CONFIG_MIPS_MT_SMTC
 161                         emt(mtflags);
 162                         local_irq_restore(irqflags);
 163 #endif /* CONFIG_MIPS_MT_SMTC */
 164                         preempt_enable();
 165                         break;
 166                 }
 167                 case DSP_BASE ... DSP_BASE + 5: {
 168                         dspreg_t *dregs;
 169
 170                         if (!cpu_has_dsp) {
 171                                 tmp = 0;
 172                                 ret = -EIO;
 173                                 goto out;
 174                         }
 175                         dregs = __get_dsp_regs(child);
 176                         tmp = (unsigned long) (dregs[addr - DSP_BASE]);
 177                         break;
 178                 }
 179                 case DSP_CONTROL:
 180                         if (!cpu_has_dsp) {
 181                                 tmp = 0;
 182                                 ret = -EIO;
 183                                 goto out;
 184                         }
 185                         tmp = child->thread.dsp.dspcontrol;
 186                         break;
 187                 default:
 188                         tmp = 0;
 189                         ret = -EIO;
 190                         goto out;
 191                 }
 192                 ret = put_user(tmp, (unsigned __user *) (unsigned long) data);
 193                 break;
 194         }
 195
 196         /*
 197          * Write 4 bytes into the other process' storage
 198          *  data is the 4 bytes that the user wants written
 199          *  addr is a pointer in the user's storage that contains an
 200          *      8 byte address in the other process where the 4 bytes
 201          *      that is to be written
 202          * (this is run in a 32-bit process looking at a 64-bit process)
 203          * when I and D space are separate, these will need to be fixed.
 204          */
 205         case PTRACE_POKETEXT_3264:
 206         case PTRACE_POKEDATA_3264: {
 207                 u32 __user * addrOthers;
 208
 209                 /* Get the addr in the other process that we want to write into */
 210                 ret = -EIO;
 211                 if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
 212                         break;
 213                 ret = 0;
 214                 if (access_process_vm(child, (u64)addrOthers, &data,
 215                                         sizeof(data), 1) == sizeof(data))
 216                         break;
 217                 ret = -EIO;
 218                 break;
 219         }
 220
 221         case PTRACE_POKEUSR: {
 222                 struct pt_regs *regs;
 223                 ret = 0;
 224                 regs = task_pt_regs(child);
 225
 226                 switch (addr) {
 227                 case 0 ... 31:
 228                         regs->regs[addr] = data;
 229                         break;
 230                 case FPR_BASE ... FPR_BASE + 31: {
 231                         fpureg_t *fregs = get_fpu_regs(child);
 232
 233                         if (!tsk_used_math(child)) {
 234                                 /* FP not yet used  */
 235                                 memset(&child->thread.fpu, ~0,
 236                                        sizeof(child->thread.fpu));
 237                                 child->thread.fpu.fcr31 = 0;
 238                         }
 239                         /*
 240                          * The odd registers are actually the high order bits
 241                          * of the values stored in the even registers - unless
 242                          * we're using r2k_switch.S.
 243                          */
 244                         if (addr & 1) {
 245                                 fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff;
 246                                 fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32;
 247                         } else {
 248                                 fregs[addr - FPR_BASE] &= ~0xffffffffLL;
 249                                 /* Must cast, lest sign extension fill upper
 250                                    bits!  */
 251                                 fregs[addr - FPR_BASE] |= (unsigned int)data;
 252                         }
 253                         break;
 254                 }
 255                 case PC:
 256                         regs->cp0_epc = data;
 257                         break;
 258                 case MMHI:
 259                         regs->hi = data;
 260                         break;
 261                 case MMLO:
 262                         regs->lo = data;
 263                         break;
 264                 case FPC_CSR:
 265                         child->thread.fpu.fcr31 = data;
 266                         break;
 267                 case DSP_BASE ... DSP_BASE + 5: {
 268                         dspreg_t *dregs;
 269
 270                         if (!cpu_has_dsp) {
 271                                 ret = -EIO;
 272                                 break;
 273                         }
 274
 275                         dregs = __get_dsp_regs(child);
 276                         dregs[addr - DSP_BASE] = data;
 277                         break;
 278                 }
 279                 case DSP_CONTROL:
 280                         if (!cpu_has_dsp) {
 281                                 ret = -EIO;
 282                                 break;
 283                         }
 284                         child->thread.dsp.dspcontrol = data;
 285                         break;
 286                 default:
 287                         /* The rest are not allowed. */
 288                         ret = -EIO;
 289                         break;
 290                 }
 291                 break;
 292                 }
 293
 294         case PTRACE_GETREGS:
 295                 ret = ptrace_getregs(child, (__s64 __user *) (__u64) data);
 296                 break;
 297
 298         case PTRACE_SETREGS:
 299                 ret = ptrace_setregs(child, (__s64 __user *) (__u64) data);
 300                 break;
 301
 302         case PTRACE_GETFPREGS:
 303                 ret = ptrace_getfpregs(child, (__u32 __user *) (__u64) data);
 304                 break;
 305
 306         case PTRACE_SETFPREGS:
 307                 ret = ptrace_setfpregs(child, (__u32 __user *) (__u64) data);
 308                 break;
 309
 310         case PTRACE_GET_THREAD_AREA:
 311                 ret = put_user(task_thread_info(child)->tp_value,
 312                                 (unsigned int __user *) (unsigned long) data);
 313                 break;
 314
 315         case PTRACE_GET_THREAD_AREA_3264:
 316                 ret = put_user(task_thread_info(child)->tp_value,
 317                                 (unsigned long __user *) (unsigned long) data);
 318                 break;
 319
 320         case PTRACE_GET_WATCH_REGS:
 321                 ret = ptrace_get_watch_regs(child,
 322                         (struct pt_watch_regs __user *) (unsigned long) addr);
 323                 break;
 324
 325         case PTRACE_SET_WATCH_REGS:
 326                 ret = ptrace_set_watch_regs(child,
 327                         (struct pt_watch_regs __user *) (unsigned long) addr);
 328                 break;
 329
 330         default:
 331                 ret = compat_ptrace_request(child, request, addr, data);
 332                 break;
 333         }
 334 out:
 335         return ret;
 336 }