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 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 "exec/semihost.h"
  26
  27 typedef enum UHIOp {
  28     UHI_exit = 1,
  29     UHI_open = 2,
  30     UHI_close = 3,
  31     UHI_read = 4,
  32     UHI_write = 5,
  33     UHI_lseek = 6,
  34     UHI_unlink = 7,
  35     UHI_fstat = 8,
  36     UHI_argc = 9,
  37     UHI_argnlen = 10,
  38     UHI_argn = 11,
  39     UHI_plog = 13,
  40     UHI_assert = 14,
  41     UHI_pread = 19,
  42     UHI_pwrite = 20,
  43     UHI_link = 22
  44 } UHIOp;
  45
  46 typedef struct UHIStat {
  47     int16_t uhi_st_dev;
  48     uint16_t uhi_st_ino;
  49     uint32_t uhi_st_mode;
  50     uint16_t uhi_st_nlink;
  51     uint16_t uhi_st_uid;
  52     uint16_t uhi_st_gid;
  53     int16_t uhi_st_rdev;
  54     uint64_t uhi_st_size;
  55     uint64_t uhi_st_atime;
  56     uint64_t uhi_st_spare1;
  57     uint64_t uhi_st_mtime;
  58     uint64_t uhi_st_spare2;
  59     uint64_t uhi_st_ctime;
  60     uint64_t uhi_st_spare3;
  61     uint64_t uhi_st_blksize;
  62     uint64_t uhi_st_blocks;
  63     uint64_t uhi_st_spare4[2];
  64 } UHIStat;
  65
  66 enum UHIOpenFlags {
  67     UHIOpen_RDONLY = 0x0,
  68     UHIOpen_WRONLY = 0x1,
  69     UHIOpen_RDWR   = 0x2,
  70     UHIOpen_APPEND = 0x8,
  71     UHIOpen_CREAT  = 0x200,
  72     UHIOpen_TRUNC  = 0x400,
  73     UHIOpen_EXCL   = 0x800
  74 };
  75
  76 /* Errno values taken from asm-mips/errno.h */
  77 static uint16_t host_to_mips_errno[] = {
  78     [ENAMETOOLONG] = 78,
  79 #ifdef EOVERFLOW
  80     [EOVERFLOW]    = 79,
  81 #endif
  82 #ifdef ELOOP
  83     [ELOOP]        = 90,
  84 #endif
  85 };
  86
  87 static int errno_mips(int err)
  88 {
  89     if (err < 0 || err >= ARRAY_SIZE(host_to_mips_errno)) {
  90         return EINVAL;
  91     } else if (host_to_mips_errno[err]) {
  92         return host_to_mips_errno[err];
  93     } else {
  94         return err;
  95     }
  96 }
  97
  98 static int copy_stat_to_target(CPUMIPSState *env, const struct stat *src,
  99                                target_ulong vaddr)
 100 {
 101     hwaddr len = sizeof(struct UHIStat);
 102     UHIStat *dst = lock_user(VERIFY_WRITE, vaddr, len, 0);
 103     if (!dst) {
 104         errno = EFAULT;
 105         return -1;
 106     }
 107
 108     dst->uhi_st_dev = tswap16(src->st_dev);
 109     dst->uhi_st_ino = tswap16(src->st_ino);
 110     dst->uhi_st_mode = tswap32(src->st_mode);
 111     dst->uhi_st_nlink = tswap16(src->st_nlink);
 112     dst->uhi_st_uid = tswap16(src->st_uid);
 113     dst->uhi_st_gid = tswap16(src->st_gid);
 114     dst->uhi_st_rdev = tswap16(src->st_rdev);
 115     dst->uhi_st_size = tswap64(src->st_size);
 116     dst->uhi_st_atime = tswap64(src->st_atime);
 117     dst->uhi_st_mtime = tswap64(src->st_mtime);
 118     dst->uhi_st_ctime = tswap64(src->st_ctime);
 119 #ifdef _WIN32
 120     dst->uhi_st_blksize = 0;
 121     dst->uhi_st_blocks = 0;
 122 #else
 123     dst->uhi_st_blksize = tswap64(src->st_blksize);
 124     dst->uhi_st_blocks = tswap64(src->st_blocks);
 125 #endif
 126     unlock_user(dst, vaddr, len);
 127     return 0;
 128 }
 129
 130 static int get_open_flags(target_ulong target_flags)
 131 {
 132     int open_flags = 0;
 133
 134     if (target_flags & UHIOpen_RDWR) {
 135         open_flags |= O_RDWR;
 136     } else if (target_flags & UHIOpen_WRONLY) {
 137         open_flags |= O_WRONLY;
 138     } else {
 139         open_flags |= O_RDONLY;
 140     }
 141
 142     open_flags |= (target_flags & UHIOpen_APPEND) ? O_APPEND : 0;
 143     open_flags |= (target_flags & UHIOpen_CREAT)  ? O_CREAT  : 0;
 144     open_flags |= (target_flags & UHIOpen_TRUNC)  ? O_TRUNC  : 0;
 145     open_flags |= (target_flags & UHIOpen_EXCL)   ? O_EXCL   : 0;
 146
 147     return open_flags;
 148 }
 149
 150 static int write_to_file(CPUMIPSState *env, target_ulong fd, target_ulong vaddr,
 151                          target_ulong len, target_ulong offset)
 152 {
 153     int num_of_bytes;
 154     void *dst = lock_user(VERIFY_READ, vaddr, len, 1);
 155     if (!dst) {
 156         errno = EFAULT;
 157         return -1;
 158     }
 159
 160     if (offset) {
 161 #ifdef _WIN32
 162         num_of_bytes = 0;
 163 #else
 164         num_of_bytes = pwrite(fd, dst, len, offset);
 165 #endif
 166     } else {
 167         num_of_bytes = write(fd, dst, len);
 168     }
 169
 170     unlock_user(dst, vaddr, 0);
 171     return num_of_bytes;
 172 }
 173
 174 static int read_from_file(CPUMIPSState *env, target_ulong fd,
 175                           target_ulong vaddr, target_ulong len,
 176                           target_ulong offset)
 177 {
 178     int num_of_bytes;
 179     void *dst = lock_user(VERIFY_WRITE, vaddr, len, 0);
 180     if (!dst) {
 181         errno = EFAULT;
 182         return -1;
 183     }
 184
 185     if (offset) {
 186 #ifdef _WIN32
 187         num_of_bytes = 0;
 188 #else
 189         num_of_bytes = pread(fd, dst, len, offset);
 190 #endif
 191     } else {
 192         num_of_bytes = read(fd, dst, len);
 193     }
 194
 195     unlock_user(dst, vaddr, len);
 196     return num_of_bytes;
 197 }
 198
 199 static int copy_argn_to_target(CPUMIPSState *env, int arg_num,
 200                                target_ulong vaddr)
 201 {
 202     int strsize = strlen(semihosting_get_arg(arg_num)) + 1;
 203     char *dst = lock_user(VERIFY_WRITE, vaddr, strsize, 0);
 204     if (!dst) {
 205         return -1;
 206     }
 207
 208     strcpy(dst, semihosting_get_arg(arg_num));
 209
 210     unlock_user(dst, vaddr, strsize);
 211     return 0;
 212 }
 213
 214 #define GET_TARGET_STRING(p, addr)              \
 215     do {                                        \
 216         p = lock_user_string(addr);             \
 217         if (!p) {                               \
 218             gpr[2] = -1;                        \
 219             gpr[3] = EFAULT;                    \
 220             goto uhi_done;                      \
 221         }                                       \
 222     } while (0)
 223
 224 #define GET_TARGET_STRINGS_2(p, addr, p2, addr2)        \
 225     do {                                                \
 226         p = lock_user_string(addr);                     \
 227         if (!p) {                                       \
 228             gpr[2] = -1;                                \
 229             gpr[3] = EFAULT;                            \
 230             goto uhi_done;                              \
 231         }                                               \
 232         p2 = lock_user_string(addr2);                   \
 233         if (!p2) {                                      \
 234             unlock_user(p, addr, 0);                    \
 235             gpr[2] = -1;                                \
 236             gpr[3] = EFAULT;                            \
 237             goto uhi_done;                              \
 238         }                                               \
 239     } while (0)
 240
 241 #define FREE_TARGET_STRING(p, gpr)              \
 242     do {                                        \
 243         unlock_user(p, gpr, 0);                 \
 244     } while (0)
 245
 246 void helper_do_semihosting(CPUMIPSState *env)
 247 {
 248     target_ulong *gpr = env->active_tc.gpr;
 249     const UHIOp op = gpr[25];
 250     char *p, *p2;
 251
 252     switch (op) {
 253     case UHI_exit:
 254         qemu_log("UHI(%d): exit(%d)\n", op, (int)gpr[4]);
 255         exit(gpr[4]);
 256     case UHI_open:
 257         GET_TARGET_STRING(p, gpr[4]);
 258         if (!strcmp("/dev/stdin", p)) {
 259             gpr[2] = 0;
 260         } else if (!strcmp("/dev/stdout", p)) {
 261             gpr[2] = 1;
 262         } else if (!strcmp("/dev/stderr", p)) {
 263             gpr[2] = 2;
 264         } else {
 265             gpr[2] = open(p, get_open_flags(gpr[5]), gpr[6]);
 266             gpr[3] = errno_mips(errno);
 267         }
 268         FREE_TARGET_STRING(p, gpr[4]);
 269         break;
 270     case UHI_close:
 271         if (gpr[4] < 3) {
 272             /* ignore closing stdin/stdout/stderr */
 273             gpr[2] = 0;
 274             goto uhi_done;
 275         }
 276         gpr[2] = close(gpr[4]);
 277         gpr[3] = errno_mips(errno);
 278         break;
 279     case UHI_read:
 280         gpr[2] = read_from_file(env, gpr[4], gpr[5], gpr[6], 0);
 281         gpr[3] = errno_mips(errno);
 282         break;
 283     case UHI_write:
 284         gpr[2] = write_to_file(env, gpr[4], gpr[5], gpr[6], 0);
 285         gpr[3] = errno_mips(errno);
 286         break;
 287     case UHI_lseek:
 288         gpr[2] = lseek(gpr[4], gpr[5], gpr[6]);
 289         gpr[3] = errno_mips(errno);
 290         break;
 291     case UHI_unlink:
 292         GET_TARGET_STRING(p, gpr[4]);
 293         gpr[2] = remove(p);
 294         gpr[3] = errno_mips(errno);
 295         FREE_TARGET_STRING(p, gpr[4]);
 296         break;
 297     case UHI_fstat:
 298         {
 299             struct stat sbuf;
 300             memset(&sbuf, 0, sizeof(sbuf));
 301             gpr[2] = fstat(gpr[4], &sbuf);
 302             gpr[3] = errno_mips(errno);
 303             if (gpr[2]) {
 304                 goto uhi_done;
 305             }
 306             gpr[2] = copy_stat_to_target(env, &sbuf, gpr[5]);
 307             gpr[3] = errno_mips(errno);
 308         }
 309         break;
 310     case UHI_argc:
 311         gpr[2] = semihosting_get_argc();
 312         break;
 313     case UHI_argnlen:
 314         if (gpr[4] >= semihosting_get_argc()) {
 315             gpr[2] = -1;
 316             goto uhi_done;
 317         }
 318         gpr[2] = strlen(semihosting_get_arg(gpr[4]));
 319         break;
 320     case UHI_argn:
 321         if (gpr[4] >= semihosting_get_argc()) {
 322             gpr[2] = -1;
 323             goto uhi_done;
 324         }
 325         gpr[2] = copy_argn_to_target(env, gpr[4], gpr[5]);
 326         break;
 327     case UHI_plog:
 328         GET_TARGET_STRING(p, gpr[4]);
 329         p2 = strstr(p, "%d");
 330         if (p2) {
 331             int char_num = p2 - p;
 332             char *buf = g_malloc(char_num + 1);
 333             strncpy(buf, p, char_num);
 334             buf[char_num] = '\0';
 335             gpr[2] = printf("%s%d%s", buf, (int)gpr[5], p2 + 2);
 336             g_free(buf);
 337         } else {
 338             gpr[2] = printf("%s", 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 uhi_done:
 373     return;
 374 }