1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Operating System Interface 4 * 5 * This provides access to useful OS routines for the sandbox architecture. 6 * They are kept in a separate file so we can include system headers. 7 * 8 * Copyright (c) 2011 The Chromium OS Authors. 9 */ 10 11 #ifndef __OS_H__ 12 #define __OS_H__ 13 14 #include <linux/types.h> 15 16 struct rtc_time; 17 struct sandbox_state; 18 19 /** 20 * Access to the OS read() system call 21 * 22 * @fd: File descriptor as returned by os_open() 23 * @buf: Buffer to place data 24 * @count: Number of bytes to read 25 * Return: number of bytes read, or -1 on error 26 */ 27 ssize_t os_read(int fd, void *buf, size_t count); 28 29 /** 30 * Access to the OS write() system call 31 * 32 * @fd: File descriptor as returned by os_open() 33 * @buf: Buffer containing data to write 34 * @count: Number of bytes to write 35 * Return: number of bytes written, or -1 on error 36 */ 37 ssize_t os_write(int fd, const void *buf, size_t count); 38 39 /** 40 * Access to the OS lseek() system call 41 * 42 * @fd: File descriptor as returned by os_open() 43 * @offset: File offset (based on whence) 44 * @whence: Position offset is relative to (see below) 45 * Return: new file offset 46 */ 47 off_t os_lseek(int fd, off_t offset, int whence); 48 49 /* Defines for "whence" in os_lseek() */ 50 #define OS_SEEK_SET 0 51 #define OS_SEEK_CUR 1 52 #define OS_SEEK_END 2 53 54 /** 55 * os_filesize() - Calculate the size of a file 56 * 57 * @fd: File descriptor as returned by os_open() 58 * Return: file size or negative error code 59 */ 60 int os_filesize(int fd); 61 62 /** 63 * Access to the OS open() system call 64 * 65 * @pathname: Pathname of file to open 66 * @flags: Flags, like OS_O_RDONLY, OS_O_RDWR 67 * Return: file descriptor, or -1 on error 68 */ 69 int os_open(const char *pathname, int flags); 70 71 #define OS_O_RDONLY 0 72 #define OS_O_WRONLY 1 73 #define OS_O_RDWR 2 74 #define OS_O_MASK 3 /* Mask for read/write flags */ 75 #define OS_O_CREAT 0100 76 #define OS_O_TRUNC 01000 77 78 /** 79 * os_close() - access to the OS close() system call 80 * 81 * @fd: File descriptor to close 82 * Return: 0 on success, -1 on error 83 */ 84 int os_close(int fd); 85 86 /** 87 * os_unlink() - access to the OS unlink() system call 88 * 89 * @pathname: Path of file to delete 90 * Return: 0 for success, other for error 91 */ 92 int os_unlink(const char *pathname); 93 94 /** 95 * os_exit() - access to the OS exit() system call 96 * 97 * This exits with the supplied return code, which should be 0 to indicate 98 * success. 99 * 100 * @exit_code: exit code for U-Boot 101 */ 102 void os_exit(int exit_code) __attribute__((noreturn)); 103 104 /** 105 * os_tty_raw() - put tty into raw mode to mimic serial console better 106 * 107 * @fd: File descriptor of stdin (normally 0) 108 * @allow_sigs: Allow Ctrl-C, Ctrl-Z to generate signals rather than 109 * be handled by U-Boot 110 */ 111 void os_tty_raw(int fd, bool allow_sigs); 112 113 /** 114 * os_fs_restore() - restore the tty to its original mode 115 * 116 * Call this to restore the original terminal mode, after it has been changed 117 * by os_tty_raw(). This is an internal function. 118 */ 119 void os_fd_restore(void); 120 121 /** 122 * os_malloc() - aquires some memory from the underlying os. 123 * 124 * @length: Number of bytes to be allocated 125 * Return: Pointer to length bytes or NULL if @length is 0 or on error 126 */ 127 void *os_malloc(size_t length); 128 129 /** 130 * os_free() - free memory previous allocated with os_malloc() 131 * 132 * This returns the memory to the OS. 133 * 134 * @ptr: Pointer to memory block to free. If this is NULL then this 135 * function does nothing 136 */ 137 void os_free(void *ptr); 138 139 /** 140 * os_realloc() - reallocate memory 141 * 142 * This follows the semantics of realloc(), so can perform an os_malloc() or 143 * os_free() depending on @ptr and @length. 144 * 145 * @ptr: pointer to previously allocated memory of NULL 146 * @length: number of bytes to allocate 147 * Return: pointer to reallocated memory or NULL if @length is 0 148 */ 149 void *os_realloc(void *ptr, size_t length); 150 151 /** 152 * os_usleep() - access to the usleep function of the os 153 * 154 * @usec: time to sleep in micro seconds 155 */ 156 void os_usleep(unsigned long usec); 157 158 /** 159 * Gets a monotonic increasing number of nano seconds from the OS 160 * 161 * Return: a monotonic increasing time scaled in nano seconds 162 */ 163 uint64_t os_get_nsec(void); 164 165 /** 166 * Parse arguments and update sandbox state. 167 * 168 * @state: sandbox state to update 169 * @argc: argument count 170 * @argv: argument vector 171 * Return: 172 * * 0 if ok, and program should continue 173 * * 1 if ok, but program should stop 174 * * -1 on error: program should terminate 175 */ 176 int os_parse_args(struct sandbox_state *state, int argc, char *argv[]); 177 178 /* 179 * enum os_dirent_t - type of directory entry 180 * 181 * Types of directory entry that we support. See also os_dirent_typename in 182 * the C file. 183 */ 184 enum os_dirent_t { 185 /** 186 * @OS_FILET_REG: regular file 187 */ 188 OS_FILET_REG, 189 /** 190 * @OS_FILET_LNK: symbolic link 191 */ 192 OS_FILET_LNK, 193 /** 194 * @OS_FILET_DIR: directory 195 */ 196 OS_FILET_DIR, 197 /** 198 * @OS_FILET_UNKNOWN: something else 199 */ 200 OS_FILET_UNKNOWN, 201 /** 202 * @OS_FILET_COUNT: number of directory entry types 203 */ 204 OS_FILET_COUNT, 205 }; 206 207 /** 208 * struct os_dirent_node - directory node 209 * 210 * A directory entry node, containing information about a single dirent 211 * 212 */ 213 struct os_dirent_node { 214 /** 215 * @next: pointer to next node, or NULL 216 */ 217 struct os_dirent_node *next; 218 /** 219 * @size: size of file in bytes 220 */ 221 ulong size; 222 /** 223 * @type: type of entry 224 */ 225 enum os_dirent_t type; 226 /** 227 * @name: name of entry 228 */ 229 char name[0]; 230 }; 231 232 /** 233 * os_dirent_ls() - get a directory listing 234 * 235 * This allocates and returns a linked list containing the directory listing. 236 * 237 * @dirname: directory to examine 238 * @headp: on return pointer to head of linked list, or NULL if none 239 * Return: 0 if ok, -ve on error 240 */ 241 int os_dirent_ls(const char *dirname, struct os_dirent_node **headp); 242 243 /** 244 * os_dirent_free() - free directory list 245 * 246 * This frees a linked list containing a directory listing. 247 * 248 * @node: pointer to head of linked list 249 */ 250 void os_dirent_free(struct os_dirent_node *node); 251 252 /** 253 * os_dirent_get_typename() - get the name of a directory entry type 254 * 255 * @type: type to check 256 * Return: 257 * string containing the name of that type, 258 * or "???" if none/invalid 259 */ 260 const char *os_dirent_get_typename(enum os_dirent_t type); 261 262 /** 263 * os_get_filesize() - get the size of a file 264 * 265 * @fname: filename to check 266 * @size: size of file is returned if no error 267 * Return: 0 on success or -1 if an error ocurred 268 */ 269 int os_get_filesize(const char *fname, loff_t *size); 270 271 /** 272 * os_putc() - write a character to the controlling OS terminal 273 * 274 * This bypasses the U-Boot console support and writes directly to the OS 275 * stdout file descriptor. 276 * 277 * @ch: haracter to write 278 */ 279 void os_putc(int ch); 280 281 /** 282 * os_puts() - write a string to the controlling OS terminal 283 * 284 * This bypasses the U-Boot console support and writes directly to the OS 285 * stdout file descriptor. 286 * 287 * @str: string to write (note that \n is not appended) 288 */ 289 void os_puts(const char *str); 290 291 /** 292 * os_write_ram_buf() - write the sandbox RAM buffer to a existing file 293 * 294 * @fname: filename to write memory to (simple binary format) 295 * Return: 0 if OK, -ve on error 296 */ 297 int os_write_ram_buf(const char *fname); 298 299 /** 300 * os_read_ram_buf() - read the sandbox RAM buffer from an existing file 301 * 302 * @fname: filename containing memory (simple binary format) 303 * Return: 0 if OK, -ve on error 304 */ 305 int os_read_ram_buf(const char *fname); 306 307 /** 308 * os_jump_to_image() - jump to a new executable image 309 * 310 * This uses exec() to run a new executable image, after putting it in a 311 * temporary file. The same arguments and environment are passed to this 312 * new image, with the addition of: 313 * 314 * -j <filename> Specifies the filename the image was written to. The 315 * calling image may want to delete this at some point. 316 * -m <filename> Specifies the file containing the sandbox memory 317 * (ram_buf) from this image, so that the new image can 318 * have access to this. It also means that the original 319 * memory filename passed to U-Boot will be left intact. 320 * 321 * @dest: buffer containing executable image 322 * @size: size of buffer 323 * Return: 0 if OK, -ve on error 324 */ 325 int os_jump_to_image(const void *dest, int size); 326 327 /** 328 * os_find_u_boot() - determine the path to U-Boot proper 329 * 330 * This function is intended to be called from within sandbox SPL. It uses 331 * a few heuristics to find U-Boot proper. Normally it is either in the same 332 * directory, or the directory above (since u-boot-spl is normally in an 333 * spl/ subdirectory when built). 334 * 335 * @fname: place to put full path to U-Boot 336 * @maxlen: maximum size of @fname 337 * @use_img: select the 'u-boot.img' file instead of the 'u-boot' ELF file 338 * @cur_prefix: prefix of current executable, e.g. "spl" or "tpl" 339 * @next_prefix: prefix of executable to find, e.g. "spl" or "" 340 * Return: 0 if OK, -NOSPC if the filename is too large, -ENOENT if not found 341 */ 342 int os_find_u_boot(char *fname, int maxlen, bool use_img, 343 const char *cur_prefix, const char *next_prefix); 344 345 /** 346 * os_spl_to_uboot() - Run U-Boot proper 347 * 348 * When called from SPL, this runs U-Boot proper. The filename is obtained by 349 * calling os_find_u_boot(). 350 * 351 * @fname: full pathname to U-Boot executable 352 * Return: 0 if OK, -ve on error 353 */ 354 int os_spl_to_uboot(const char *fname); 355 356 /** 357 * os_localtime() - read the current system time 358 * 359 * This reads the current Local Time and places it into the provided 360 * structure. 361 * 362 * @rt: place to put system time 363 */ 364 void os_localtime(struct rtc_time *rt); 365 366 /** 367 * os_abort() - raise SIGABRT to exit sandbox (e.g. to debugger) 368 */ 369 void os_abort(void) __attribute__((noreturn)); 370 371 /** 372 * os_mprotect_allow() - Remove write-protection on a region of memory 373 * 374 * The start and length will be page-aligned before use. 375 * 376 * @start: Region start 377 * @len: Region length in bytes 378 * Return: 0 if OK, -1 on error from mprotect() 379 */ 380 int os_mprotect_allow(void *start, size_t len); 381 382 /** 383 * os_write_file() - write a file to the host filesystem 384 * 385 * This can be useful when debugging for writing data out of sandbox for 386 * inspection by external tools. 387 * 388 * @name: File path to write to 389 * @buf: Data to write 390 * @size: Size of data to write 391 * Return: 0 if OK, -ve on error 392 */ 393 int os_write_file(const char *name, const void *buf, int size); 394 395 /** 396 * os_read_file() - Read a file from the host filesystem 397 * 398 * This can be useful when reading test data into sandbox for use by test 399 * routines. The data is allocated using os_malloc() and should be freed by 400 * the caller. 401 * 402 * @name: File path to read from 403 * @bufp: Returns buffer containing data read 404 * @sizep: Returns size of data 405 * Return: 0 if OK, -ve on error 406 */ 407 int os_read_file(const char *name, void **bufp, int *sizep); 408 409 /** 410 * os_map_file() - Map a file from the host filesystem into memory 411 * 412 * This can be useful when to provide a backing store for an emulated device 413 * 414 * @pathname: File pathname to map 415 * @os_flags: Flags, like OS_O_RDONLY, OS_O_RDWR 416 * @bufp: Returns buffer containing the file 417 * @sizep: Returns size of data 418 * Return: 0 if OK, -ve on error 419 */ 420 int os_map_file(const char *pathname, int os_flags, void **bufp, int *sizep); 421 422 /* 423 * os_find_text_base() - Find the text section in this running process 424 * 425 * This tries to find the address of the text section in this running process. 426 * It can be useful to map the address of functions to the address listed in 427 * the u-boot.map file. 428 * 429 * Return: address if found, else NULL 430 */ 431 void *os_find_text_base(void); 432 433 /** 434 * os_relaunch() - restart the sandbox 435 * 436 * This functions is used to implement the cold reboot of the sand box. 437 * @argv\[0] specifies the binary that is started while the calling process 438 * stops immediately. If the new binary cannot be started, the process is 439 * terminated and 1 is set as shell return code. 440 * 441 * The PID of the process stays the same. All file descriptors that have not 442 * been opened with O_CLOEXEC stay open including stdin, stdout, stderr. 443 * 444 * @argv: NULL terminated list of command line parameters 445 */ 446 void os_relaunch(char *argv[]); 447 448 /** 449 * os_setup_signal_handlers() - setup signal handlers 450 * 451 * Install signal handlers for SIGBUS and SIGSEGV. 452 * 453 * Return: 0 for success 454 */ 455 int os_setup_signal_handlers(void); 456 457 /** 458 * os_signal_action() - handle a signal 459 * 460 * @sig: signal 461 * @pc: program counter 462 */ 463 void os_signal_action(int sig, unsigned long pc); 464 465 /** 466 * os_get_time_offset() - get time offset 467 * 468 * Get the time offset from environment variable UBOOT_SB_TIME_OFFSET. 469 * 470 * Return: offset in seconds 471 */ 472 long os_get_time_offset(void); 473 474 /** 475 * os_set_time_offset() - set time offset 476 * 477 * Save the time offset in environment variable UBOOT_SB_TIME_OFFSET. 478 * 479 * @offset: offset in seconds 480 */ 481 void os_set_time_offset(long offset); 482 483 #endif 484