target/mips/mips-semi.c

   1 /*
   2  * Unified Hosting Interface syscalls.
   3  *
   4  * Copyright (c) 2015 Imagination Technologies
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include "qemu/osdep.h"
  21 #include "cpu.h"
  22 #include "qemu/log.h"
  23 #include "exec/helper-proto.h"
  24 #include "exec/softmmu-semi.h"
  25 #include "hw/semihosting/semihost.h"
  26 #include "hw/semihosting/console.h"
  27
  28 typedef enum UHIOp {
  29     UHI_exit = 1,
  30     UHI_open = 2,
  31     UHI_close = 3,
  32     UHI_read = 4,
  33     UHI_write = 5,
  34     UHI_lseek = 6,
  35     UHI_unlink = 7,
  36     UHI_fstat = 8,
  37     UHI_argc = 9,
  38     UHI_argnlen = 10,
  39     UHI_argn = 11,
  40     UHI_plog = 13,
  41     UHI_assert = 14,
  42     UHI_pread = 19,
  43     UHI_pwrite = 20,
  44     UHI_link = 22
  45 } UHIOp;
  46
  47 typedef struct UHIStat {
  48     int16_t uhi_st_dev;
  49     uint16_t uhi_st_ino;
  50     uint32_t uhi_st_mode;
  51     uint16_t uhi_st_nlink;
  52     uint16_t uhi_st_uid;
  53     uint16_t uhi_st_gid;
  54     int16_t uhi_st_rdev;
  55     uint64_t uhi_st_size;
  56     uint64_t uhi_st_atime;
  57     uint64_t uhi_st_spare1;
  58     uint64_t uhi_st_mtime;
  59     uint64_t uhi_st_spare2;
  60     uint64_t uhi_st_ctime;
  61     uint64_t uhi_st_spare3;
  62     uint64_t uhi_st_blksize;
  63     uint64_t uhi_st_blocks;
  64     uint64_t uhi_st_spare4[2];
  65 } UHIStat;
  66
  67 enum UHIOpenFlags {
  68     UHIOpen_RDONLY = 0x0,
  69     UHIOpen_WRONLY = 0x1,
  70     UHIOpen_RDWR   = 0x2,
  71     UHIOpen_APPEND = 0x8,
  72     UHIOpen_CREAT  = 0x200,
  73     UHIOpen_TRUNC  = 0x400,
  74     UHIOpen_EXCL   = 0x800
  75 };
  76
  77 /* Errno values taken from asm-mips/errno.h */
  78 static uint16_t host_to_mips_errno[] = {
  79     [ENAMETOOLONG] = 78,
  80 #ifdef EOVERFLOW
  81     [EOVERFLOW]    = 79,
  82 #endif
  83 #ifdef ELOOP
  84     [ELOOP]        = 90,
  85 #endif
  86 };
  87
  88 static int errno_mips(int err)
  89 {
  90     if (err < 0 || err >= ARRAY_SIZE(host_to_mips_errno)) {
  91         return EINVAL;
  92     } else if (host_to_mips_errno[err]) {
  93         return host_to_mips_errno[err];
  94     } else {
  95         return err;
  96     }
  97 }
  98
  99 static int copy_stat_to_target(CPUMIPSState *env, const struct stat *src,
 100                                target_ulong vaddr)
 101 {
 102     hwaddr len = sizeof(struct UHIStat);
 103     UHIStat *dst = lock_user(VERIFY_WRITE, vaddr, len, 0);
 104     if (!dst) {
 105         errno = EFAULT;
 106         return -1;
 107     }
 108
 109     dst->uhi_st_dev = tswap16(src->st_dev);
 110     dst->uhi_st_ino = tswap16(src->st_ino);
 111     dst->uhi_st_mode = tswap32(src->st_mode);
 112     dst->uhi_st_nlink = tswap16(src->st_nlink);
 113     dst->uhi_st_uid = tswap16(src->st_uid);
 114     dst->uhi_st_gid = tswap16(src->st_gid);
 115     dst->uhi_st_rdev = tswap16(src->st_rdev);
 116     dst->uhi_st_size = tswap64(src->st_size);
 117     dst->uhi_st_atime = tswap64(src->st_atime);
 118     dst->uhi_st_mtime = tswap64(src->st_mtime);
 119     dst->uhi_st_ctime = tswap64(src->st_ctime);
 120 #ifdef _WIN32
 121     dst->uhi_st_blksize = 0;
 122     dst->uhi_st_blocks = 0;
 123 #else
 124     dst->uhi_st_blksize = tswap64(src->st_blksize);
 125     dst->uhi_st_blocks = tswap64(src->st_blocks);
 126 #endif
 127     unlock_user(dst, vaddr, len);
 128     return 0;
 129 }
 130
 131 static int get_open_flags(target_ulong target_flags)
 132 {
 133     int open_flags = 0;
 134
 135     if (target_flags & UHIOpen_RDWR) {
 136         open_flags |= O_RDWR;
 137     } else if (target_flags & UHIOpen_WRONLY) {
 138         open_flags |= O_WRONLY;
 139     } else {
 140         open_flags |= O_RDONLY;
 141     }
 142
 143     open_flags |= (target_flags & UHIOpen_APPEND) ? O_APPEND : 0;
 144     open_flags |= (target_flags & UHIOpen_CREAT)  ? O_CREAT  : 0;
 145     open_flags |= (target_flags & UHIOpen_TRUNC)  ? O_TRUNC  : 0;
 146     open_flags |= (target_flags & UHIOpen_EXCL)   ? O_EXCL   : 0;
 147
 148     return open_flags;
 149 }
 150
 151 static int write_to_file(CPUMIPSState *env, target_ulong fd, target_ulong vaddr,
 152                          target_ulong len, target_ulong offset)
 153 {
 154     int num_of_bytes;
 155     void *dst = lock_user(VERIFY_READ, vaddr, len, 1);
 156     if (!dst) {
 157         errno = EFAULT;
 158         return -1;
 159     }
 160
 161     if (offset) {
 162 #ifdef _WIN32
 163         num_of_bytes = 0;
 164 #else
 165         num_of_bytes = pwrite(fd, dst, len, offset);
 166 #endif
 167     } else {
 168         num_of_bytes = write(fd, dst, len);
 169     }
 170
 171     unlock_user(dst, vaddr, 0);
 172     return num_of_bytes;
 173 }
 174
 175 static int read_from_file(CPUMIPSState *env, target_ulong fd,
 176                           target_ulong vaddr, target_ulong len,
 177                           target_ulong offset)
 178 {
 179     int num_of_bytes;
 180     void *dst = lock_user(VERIFY_WRITE, vaddr, len, 0);
 181     if (!dst) {
 182         errno = EFAULT;
 183         return -1;
 184     }
 185
 186     if (offset) {
 187 #ifdef _WIN32
 188         num_of_bytes = 0;
 189 #else
 190         num_of_bytes = pread(fd, dst, len, offset);
 191 #endif
 192     } else {
 193         num_of_bytes = read(fd, dst, len);
 194     }
 195
 196     unlock_user(dst, vaddr, len);
 197     return num_of_bytes;
 198 }
 199
 200 static int copy_argn_to_target(CPUMIPSState *env, int arg_num,
 201                                target_ulong vaddr)
 202 {
 203     int strsize = strlen(semihosting_get_arg(arg_num)) + 1;
 204     char *dst = lock_user(VERIFY_WRITE, vaddr, strsize, 0);
 205     if (!dst) {
 206         return -1;
 207     }
 208
 209     strcpy(dst, semihosting_get_arg(arg_num));
 210
 211     unlock_user(dst, vaddr, strsize);
 212     return 0;
 213 }
 214
 215 #define GET_TARGET_STRING(p, addr)              \
 216     do {                                        \
 217         p = lock_user_string(addr);             \
 218         if (!p) {                               \
 219             gpr[2] = -1;                        \
 220             gpr[3] = EFAULT;                    \
 221             return;                             \
 222         }                                       \
 223     } while (0)
 224
 225 #define GET_TARGET_STRINGS_2(p, addr, p2, addr2)        \
 226     do {                                                \
 227         p = lock_user_string(addr);                     \
 228         if (!p) {                                       \
 229             gpr[2] = -1;                                \
 230             gpr[3] = EFAULT;                            \
 231             return;                                     \
 232         }                                               \
 233         p2 = lock_user_string(addr2);                   \
 234         if (!p2) {                                      \
 235             unlock_user(p, addr, 0);                    \
 236             gpr[2] = -1;                                \
 237             gpr[3] = EFAULT;                            \
 238             return;                                     \
 239         }                                               \
 240     } while (0)
 241
 242 #define FREE_TARGET_STRING(p, gpr)              \
 243     do {                                        \
 244         unlock_user(p, gpr, 0);                 \
 245     } while (0)
 246
 247 void helper_do_semihosting(CPUMIPSState *env)
 248 {
 249     target_ulong *gpr = env->active_tc.gpr;
 250     const UHIOp op = gpr[25];
 251     char *p, *p2;
 252
 253     switch (op) {
 254     case UHI_exit:
 255         qemu_log("UHI(%d): exit(%d)\n", op, (int)gpr[4]);
 256         exit(gpr[4]);
 257     case UHI_open:
 258         GET_TARGET_STRING(p, gpr[4]);
 259         if (!strcmp("/dev/stdin", p)) {
 260             gpr[2] = 0;
 261         } else if (!strcmp("/dev/stdout", p)) {
 262             gpr[2] = 1;
 263         } else if (!strcmp("/dev/stderr", p)) {
 264             gpr[2] = 2;
 265         } else {
 266             gpr[2] = open(p, get_open_flags(gpr[5]), gpr[6]);
 267             gpr[3] = errno_mips(errno);
 268         }
 269         FREE_TARGET_STRING(p, gpr[4]);
 270         break;
 271     case UHI_close:
 272         if (gpr[4] < 3) {
 273             /* ignore closing stdin/stdout/stderr */
 274             gpr[2] = 0;
 275             return;
 276         }
 277         gpr[2] = close(gpr[4]);
 278         gpr[3] = errno_mips(errno);
 279         break;
 280     case UHI_read:
 281         gpr[2] = read_from_file(env, gpr[4], gpr[5], gpr[6], 0);
 282         gpr[3] = errno_mips(errno);
 283         break;
 284     case UHI_write:
 285         gpr[2] = write_to_file(env, gpr[4], gpr[5], gpr[6], 0);
 286         gpr[3] = errno_mips(errno);
 287         break;
 288     case UHI_lseek:
 289         gpr[2] = lseek(gpr[4], gpr[5], gpr[6]);
 290         gpr[3] = errno_mips(errno);
 291         break;
 292     case UHI_unlink:
 293         GET_TARGET_STRING(p, gpr[4]);
 294         gpr[2] = remove(p);
 295         gpr[3] = errno_mips(errno);
 296         FREE_TARGET_STRING(p, gpr[4]);
 297         break;
 298     case UHI_fstat:
 299         {
 300             struct stat sbuf;
 301             memset(&sbuf, 0, sizeof(sbuf));
 302             gpr[2] = fstat(gpr[4], &sbuf);
 303             gpr[3] = errno_mips(errno);
 304             if (gpr[2]) {
 305                 return;
 306             }
 307             gpr[2] = copy_stat_to_target(env, &sbuf, gpr[5]);
 308             gpr[3] = errno_mips(errno);
 309         }
 310         break;
 311     case UHI_argc:
 312         gpr[2] = semihosting_get_argc();
 313         break;
 314     case UHI_argnlen:
 315         if (gpr[4] >= semihosting_get_argc()) {
 316             gpr[2] = -1;
 317             return;
 318         }
 319         gpr[2] = strlen(semihosting_get_arg(gpr[4]));
 320         break;
 321     case UHI_argn:
 322         if (gpr[4] >= semihosting_get_argc()) {
 323             gpr[2] = -1;
 324             return;
 325         }
 326         gpr[2] = copy_argn_to_target(env, gpr[4], gpr[5]);
 327         break;
 328     case UHI_plog:
 329         GET_TARGET_STRING(p, gpr[4]);
 330         p2 = strstr(p, "%d");
 331         if (p2) {
 332             int char_num = p2 - p;
 333             GString *s = g_string_new_len(p, char_num);
 334             g_string_append_printf(s, "%d%s", (int)gpr[5], p2 + 2);
 335             gpr[2] = qemu_semihosting_log_out(s->str, s->len);
 336             g_string_free(s, true);
 337         } else {
 338             gpr[2] = qemu_semihosting_log_out(p, strlen(p));
 339         }
 340         FREE_TARGET_STRING(p, gpr[4]);
 341         break;
 342     case UHI_assert:
 343         GET_TARGET_STRINGS_2(p, gpr[4], p2, gpr[5]);
 344         printf("assertion '");
 345         printf("\"%s\"", p);
 346         printf("': file \"%s\", line %d\n", p2, (int)gpr[6]);
 347         FREE_TARGET_STRING(p2, gpr[5]);
 348         FREE_TARGET_STRING(p, gpr[4]);
 349         abort();
 350         break;
 351     case UHI_pread:
 352         gpr[2] = read_from_file(env, gpr[4], gpr[5], gpr[6], gpr[7]);
 353         gpr[3] = errno_mips(errno);
 354         break;
 355     case UHI_pwrite:
 356         gpr[2] = write_to_file(env, gpr[4], gpr[5], gpr[6], gpr[7]);
 357         gpr[3] = errno_mips(errno);
 358         break;
 359 #ifndef _WIN32
 360     case UHI_link:
 361         GET_TARGET_STRINGS_2(p, gpr[4], p2, gpr[5]);
 362         gpr[2] = link(p, p2);
 363         gpr[3] = errno_mips(errno);
 364         FREE_TARGET_STRING(p2, gpr[5]);
 365         FREE_TARGET_STRING(p, gpr[4]);
 366         break;
 367 #endif
 368     default:
 369         fprintf(stderr, "Unknown UHI operation %d\n", op);
 370         abort();
 371     }
 372     return;
 373 }