2 * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 /** @addtogroup lwext4
34 * @brief Ext4 high level operations (files, directories, mount points...).
35 * Client has to include only this file.
48 /********************************FILE OPEN FLAGS*****************************/
50 #if CONFIG_HAVE_OWN_OFLAGS
77 #define O_APPEND 02000
80 /********************************FILE SEEK FLAGS*****************************/
99 #include "ext4_config.h"
100 #include "ext4_types.h"
101 #include "ext4_blockdev.h"
103 /********************************OS LOCK INFERFACE***************************/
105 /**@brief OS dependent lock interface.*/
108 /**@brief Lock access to mount point*/
111 /**@brief Unlock access to mount point*/
112 void (*unlock)(void);
115 /********************************FILE DESCRIPTOR*****************************/
117 /**@brief File descriptor*/
118 typedef struct ext4_file {
120 /**@brief Mount point handle.*/
121 struct ext4_mountpoint *mp;
123 /**@brief File inode id*/
126 /**@brief Open flags.*/
129 /**@brief File size.*/
132 /**@brief File position*/
136 /*****************************DIRECTORY DESCRIPTOR***************************/
138 /**@brief Directory entry descriptor. Copy from ext4_types.h*/
139 typedef struct ext4_direntry {
141 uint16_t entry_length;
147 typedef struct ext4_dir {
148 /**@brief File descriptor*/
150 /**@brief Current directory entry.*/
152 /**@brief Next entry offset*/
156 /********************************MOUNT OPERATIONS****************************/
158 /**@brief Register a block device to a name.
159 * @warning Block device has to be filled by
160 * @ref EXT4_BLOCKDEV_STATIC_INSTANCE. Block cache may be created
161 * @ref EXT4_BCACHE_STATIC_INSTANCE.
162 * Block cache may by created automatically when bc parameter is 0.
163 * @param bd block device
164 * @param bd block device cache (0 = automatic cache mode)
165 * @param dev_name register name
166 * @param standard error code*/
167 int ext4_device_register(struct ext4_blockdev *bd, struct ext4_bcache *bc,
168 const char *dev_name);
170 /**@brief Mount a block device with EXT4 partition to the mount point.
171 * @param dev_name block device name (@ref ext4_device_register)
172 * @param mount_point mount point, for example
175 * - /my_second_partition/
177 * @return standard error code */
178 int ext4_mount(const char *dev_name, const char *mount_point);
180 /**@brief Umount operation.
181 * @param mount_point mount name
182 * @return standard error code */
183 int ext4_umount(const char *mount_point);
185 int ext4_journal_start(const char *mount_point);
187 int ext4_journal_stop(const char *mount_point);
189 /**@brief Journal recovery.
190 * @param mount_point mount point
191 * @warning Must be called after @ref ext4_mount
192 * @return standard error code */
193 int ext4_recover(const char *mount_point);
195 /**@brief Some of the filesystem stats.*/
196 struct ext4_mount_stats {
197 uint32_t inodes_count;
198 uint32_t free_inodes_count;
199 uint64_t blocks_count;
200 uint64_t free_blocks_count;
203 uint32_t block_group_count;
204 uint32_t blocks_per_group;
205 uint32_t inodes_per_group;
207 char volume_name[16];
210 /**@brief Get file system params.
211 * @param mount_point mount path
212 * @param stats ext fs stats
213 * @return standard error code */
214 int ext4_mount_point_stats(const char *mount_point,
215 struct ext4_mount_stats *stats);
217 /**@brief Setup OS lock routines.
218 * @param mount_point mount path
219 * @param locks - lock and unlock functions
220 * @return standard error code */
221 int ext4_mount_setup_locks(const char *mount_point,
222 const struct ext4_lock *locks);
224 /**@brief Acquire the filesystem superblock pointer of a mp.
225 * @param mount_point mount path
226 * @param superblock pointer
227 * @return standard error code */
228 int ext4_get_sblock(const char *mount_point, struct ext4_sblock **sb);
230 /**@brief Enable/disable write back cache mode.
231 * @warning Default model of cache is write trough. It means that when You do:
235 * < --- data is flushed to physical drive
238 * ext4_cache_write_back(..., 1);
241 * < --- data is NOT flushed to physical drive
242 * ext4_cache_write_back(..., 0);
243 * < --- when write back mode is disabled all
244 * cache data will be flushed
245 * To enable write back mode permanently just call this function
246 * once after ext4_mount (and disable before ext4_umount).
248 * Some of the function use write back cache mode internally.
249 * If you enable write back mode twice you have to disable it twice
252 * ext4_cache_write_back(..., 1);
253 * ext4_cache_write_back(..., 1);
255 * ext4_cache_write_back(..., 0);
256 * ext4_cache_write_back(..., 0);
258 * Write back mode is useful when you want to create a lot of empty
261 * @param path mount point path
262 * @param on enable/disable
264 * @return standard error code */
265 int ext4_cache_write_back(const char *path, bool on);
267 /********************************FILE OPERATIONS*****************************/
269 /**@brief Remove file by path.
270 * @param path path to file
271 * @return standard error code */
272 int ext4_fremove(const char *path);
274 /**@brief create a hardlink for a file.
275 * @param path path to file
276 * @param hardlink_path path of hardlink
277 * @return standard error code */
278 int ext4_flink(const char *path, const char *hardlink_path);
280 /**@brief Rename file
282 * @param new_path destination
283 * @return standard error code */
284 int ext4_frename(const char *path, const char *new_path);
286 /**@brief File open function.
287 * @param path filename (has to start from mount point)
288 * /my_partition/my_file
289 * @param flags open file flags
290 * |---------------------------------------------------------------|
291 * | r or rb O_RDONLY |
292 * |---------------------------------------------------------------|
293 * | w or wb O_WRONLY|O_CREAT|O_TRUNC |
294 * |---------------------------------------------------------------|
295 * | a or ab O_WRONLY|O_CREAT|O_APPEND |
296 * |---------------------------------------------------------------|
297 * | r+ or rb+ or r+b O_RDWR |
298 * |---------------------------------------------------------------|
299 * | w+ or wb+ or w+b O_RDWR|O_CREAT|O_TRUNC |
300 * |---------------------------------------------------------------|
301 * | a+ or ab+ or a+b O_RDWR|O_CREAT|O_APPEND |
302 * |---------------------------------------------------------------|
304 * @return standard error code*/
305 int ext4_fopen(ext4_file *f, const char *path, const char *flags);
307 /**@brief Alternate file open function.
308 * @param filename, (has to start from mount point)
309 * /my_partition/my_file
310 * @param flags open file flags
311 * @return standard error code*/
312 int ext4_fopen2(ext4_file *f, const char *path, int flags);
314 /**@brief File close function.
315 * @param f file handle
316 * @return standard error code*/
317 int ext4_fclose(ext4_file *f);
319 /**@brief Fill in the ext4_inode buffer.
320 * @param path fetch inode data of the path
321 * @param ret_ino the inode id of the path
322 * @param ext4_inode buffer
323 * @return standard error code*/
324 int ext4_fill_raw_inode(const char *path, uint32_t *ret_ino,
325 struct ext4_inode *inode);
327 /**@brief File truncate function.
328 * @param f file handle
329 * @param new file size
330 * @return standard error code*/
331 int ext4_ftruncate(ext4_file *f, uint64_t size);
333 /**@brief Read data from file.
334 * @param f file handle
335 * @param buf output buffer
336 * @param size bytes to read
337 * @param rcnt bytes read (may be NULL)
338 * @return standard error code*/
339 int ext4_fread(ext4_file *f, void *buf, size_t size, size_t *rcnt);
341 /**@brief Write data to file.
342 * @param f file handle
343 * @param buf data to write
344 * @param size write length
345 * @param wcnt bytes written (may be NULL)
346 * @return standard error code*/
347 int ext4_fwrite(ext4_file *f, const void *buf, size_t size, size_t *wcnt);
349 /**@brief File seek operation.
350 * @param f file handle
351 * @param offset offset to seek
352 * @param origin seek type:
356 * @return standard error code*/
357 int ext4_fseek(ext4_file *f, uint64_t offset, uint32_t origin);
359 /**@brief Get file position.
360 * @param f file handle
361 * @return actual file position */
362 uint64_t ext4_ftell(ext4_file *f);
364 /**@brief Get file size.
365 * @param f file handle
366 * @return file size */
367 uint64_t ext4_fsize(ext4_file *f);
369 /**@brief Change file/directory/link mode bits
370 * @param path to file/dir/link
371 * @param mode new mode bits (for example 0777)
372 * @return standard error code*/
373 int ext4_chmod(const char *path, uint32_t mode);
375 /**@brief Change file owner and group
376 * @param path to file/dir/link
378 * @param gid group id
379 * @return standard error code*/
380 int ext4_chown(const char *path, uint32_t uid, uint32_t gid);
382 /**@brief Set file access time
383 * @param path to file/dir/link
384 * @param atime access timestamp
385 * @return standard error code*/
386 int ext4_file_set_atime(const char *path, uint32_t atime);
388 /**@brief Set file modify time
389 * @param path to file/dir/link
390 * @param mtime modify timestamp
391 * @return standard error code*/
392 int ext4_file_set_mtime(const char *path, uint32_t mtime);
394 /**@brief Set file change time
395 * @param path to file/dir/link
396 * @param ctime change timestamp
397 * @return standard error code*/
398 int ext4_file_set_ctime(const char *path, uint32_t ctime);
400 /**@brief Create symbolic link
401 * @param target destination path
402 * @param path source entry
403 * @return standard error code*/
404 int ext4_fsymlink(const char *target, const char *path);
407 /**@brief Read symbolic link payload
408 * @param path to symlink
409 * @param buf output buffer
410 * @param bufsize output buffer max size
411 * @param rcnt bytes read
412 * @return standard error code*/
413 int ext4_readlink(const char *path, char *buf, size_t bufsize, size_t *rcnt);
415 /**@brief Set extended attribute
416 * @param path to entry
418 * TODO: write detailed description
420 int ext4_setxattr(const char *path, const char *name, size_t name_len,
421 const void *data, size_t data_size, bool replace);
423 /**@brief Get extended attribute
424 * @param path to entry
426 * TODO: write detailed description
428 int ext4_getxattr(const char *path, const char *name, size_t name_len,
429 void *buf, size_t buf_size, size_t *data_size);
431 /**@brief List extended attributes
432 * @param path to entry
434 * TODO: write detailed description
436 int ext4_listxattr(const char *path, char *list, size_t size, size_t *ret_size);
438 /**@brief Remove extended attribute
439 * @param path to entry
441 * TODO: write detailed description
443 int ext4_removexattr(const char *path, const char *name, size_t name_len);
446 /*********************************DIRECTORY OPERATION***********************/
448 /**@brief Recursive directory remove.
449 * @param path directory path to remove
450 * @return standard error code*/
451 int ext4_dir_rm(const char *path);
453 /**@brief Create new directory.
454 * @param name new directory name
455 * @return standard error code*/
456 int ext4_dir_mk(const char *path);
458 /**@brief Directory open.
459 * @param d directory handle
460 * @param path directory path
461 * @return standard error code*/
462 int ext4_dir_open(ext4_dir *d, const char *path);
464 /**@brief Directory close.
465 * @param d directory handle
466 * @return standard error code*/
467 int ext4_dir_close(ext4_dir *d);
469 /**@brief Return next directory entry.
470 * @param d directory handle
472 * @return directory entry id (NULL if no entry)*/
473 const ext4_direntry *ext4_dir_entry_next(ext4_dir *d);
475 /**@brief Rewine directory entry offset.
476 * @param d directory handle*/
477 void ext4_dir_entry_rewind(ext4_dir *d);
479 /**@brief Test journal functionality
480 * @param mount_point mount point, for example
483 * - /my_second_partition/
485 * @return standard error code */
486 int ext4_test_journal(const char *mount_point);