1/* @title: Ext2 */
2#include <block/bcache.h>
3#include <block/block.h>
4#include <compiler.h>
5#include <errno.h>
6#include <fs/vfs.h>
7#include <mem/alloc.h>
8#include <stdint.h>
9#include <sync/spinlock.h>
10#include <types/types.h>
11
12extern uint64_t PTRS_PER_BLOCK;
13
14#define EXT2_PRIO_DIRENT BIO_RQ_MEDIUM
15#define EXT2_PRIO_INODE BIO_RQ_MEDIUM
16#define EXT2_PRIO_DATA BIO_RQ_HIGH
17#define EXT2_PRIO_BITMAPS BIO_RQ_BACKGROUND
18#define EXT2_PRIO_SBLOCK BIO_RQ_LOW
19
20#define EXT2_NBLOCKS 15
21#define EXT2_SUPERBLOCK_OFFSET 1024
22#define EXT2_SIGNATURE_OFFSET 0x38
23#define EXT2_SIGNATURE 0xEF53
24#define EXT2_NAME_LEN 255
25#define EXT2_ROOT_INODE 2
26#define EXT2_S_IFSOCK 0xC000 // socket
27#define EXT2_S_IFLNK 0xA000 // symbolic link
28#define EXT2_S_IFREG 0x8000 // regular file
29#define EXT2_S_IFBLK 0x6000 // block device
30#define EXT2_S_IFDIR 0x4000 // directory
31#define EXT2_S_IFCHR 0x2000 // character device
32#define EXT2_S_IFIFO 0x1000 // FIFO
33#define EXT2_S_IFMT 0xF000 // mask to extract file type from i_mode
34#define EXT2_S_PERMS 0x0FFF // lower 12 bits: special + rwx bits
35#define EXT2_S_IRWXU 0x01C0 // owner permissions - ALL
36#define EXT2_S_IRWXG 0x0038 // group permissions - ALL
37#define EXT2_S_IRWXO 0x0007 // others permissions - ALL
38#define EXT2_S_PERMS_ONLY 0x01FF // rwx bits only
39
40#define EXT2_S_IRUSR 0x0100 // Owner can read
41#define EXT2_S_IWUSR 0x0080 // Owner can write
42#define EXT2_S_IXUSR 0x0040 // Owner can execute
43#define EXT2_S_IRGRP 0x0020 // Group can read
44#define EXT2_S_IWGRP 0x0010 // Group can write
45#define EXT2_S_IXGRP 0x0008 // Group can execute
46#define EXT2_S_IROTH 0x0004 // Others can read
47#define EXT2_S_IWOTH 0x0002 // Others can write
48#define EXT2_S_IXOTH 0x0001 // Others can execute
49
50#define EXT2_FT_UNKNOWN 0 // Unknown file type
51#define EXT2_FT_REG_FILE 1 // Regular file
52#define EXT2_FT_DIR 2 // Directory
53#define EXT2_FT_CHRDEV 3 // Character device
54#define EXT2_FT_BLKDEV 4 // Block device
55#define EXT2_FT_FIFO 5 // FIFO (named pipe)
56#define EXT2_FT_SOCK 6 // Unix domain socket
57#define EXT2_FT_SYMLINK 7 // Symbolic link
58#define EXT2_FT_MAX 8 // Number of defined file types
59
60// ext2 inode flags
61#define EXT2_SECRM_FL 0x00000001 // Secure deletion
62#define EXT2_UNRM_FL 0x00000002 // Undelete
63#define EXT2_COMPR_FL 0x00000004 // Compress file
64#define EXT2_SYNC_FL 0x00000008 // Synchronous updates
65#define EXT2_IMMUTABLE_FL 0x00000010 // Immutable file
66#define EXT2_APPEND_FL 0x00000020 // Writes only append
67#define EXT2_NODUMP_FL 0x00000040 // Don't include in backups
68#define EXT2_NOATIME_FL 0x00000080 // Don't update access time
69
70#define EXT2_DIRTY_FL 0x00000100 // Dirty (compress support)
71#define EXT2_COMPRBLK_FL 0x00000200 // One or more compressed clusters
72#define EXT2_NOCOMPR_FL 0x00000400 // Don't compress
73#define EXT2_ECOMPR_FL 0x00000800 // Compression error
74#define EXT2_IMAGIC_FL 0x00002000 // AFS directory
75#define EXT2_JOURNAL_DATA_FL 0x00004000 // Write data to journal (data=journal)
76
77#define EXT2_NOTAIL_FL 0x00008000 // File tail not merged (reiserfs)
78#define EXT2_DIRSYNC_FL 0x00010000 // Directory sync updates
79#define EXT2_TOPDIR_FL 0x00020000 // Top of directory hierarchy
80#define EXT2_HUGE_FILE_FL 0x00040000 // Set to each huge file
81#define EXT2_EXTENTS_FL 0x00080000 // Inode uses extents
82
83#define EXT2_EA_INODE_FL 0x00200000 // Inode stores extended attributes
84#define EXT2_INLINE_DATA_FL 0x10000000 // Data is stored inline in inode
85#define EXT2_PROJINHERIT_FL 0x20000000 // Project ID inheritance
86
87#define EXT2_RESERVED_FL 0x80000000 // Reserved for ext3/4
88
89// Useful masks
90#define EXT2_FL_USER_VISIBLE 0x000BDFFF // User-visible flags
91#define EXT2_FL_USER_MODIFIABLE \
92 (EXT2_FL_USER_VISIBLE & ~(EXT2_SECRM_FL | EXT2_UNRM_FL))
93
94#define MIN(x, y) ((x > y) ? y : x)
95
96#define MAKE_NOP_CALLBACK \
97 static bool nop_callback(struct ext2_fs *fs, struct ext2_dir_entry *entry, \
98 void *ctx_ptr, uint32_t block_num, \
99 uint32_t entry_num, uint32_t entry_offset) { \
100 (void) fs; \
101 (void) entry_offset; \
102 (void) entry; \
103 (void) ctx_ptr; \
104 (void) block_num; \
105 (void) entry_num; \
106 return false; \
107 }
108
109struct ext2_sblock {
110 uint32_t inodes_count;
111 uint32_t blocks_count;
112 uint32_t r_blocks_count;
113 uint32_t free_blocks_count;
114 uint32_t free_inodes_count;
115 uint32_t first_data_block;
116 uint32_t log_block_size;
117 uint32_t log_frag_size;
118 uint32_t blocks_per_group;
119 uint32_t frags_per_group;
120 uint32_t inodes_per_group;
121 uint32_t mtime;
122 uint32_t wtime;
123 uint16_t mnt_count;
124 uint16_t max_mnt_count;
125 uint16_t magic;
126 uint16_t state;
127 uint16_t errors;
128 uint16_t minor_rev_level;
129 uint32_t lastcheck;
130 uint32_t checkinterval;
131 uint32_t creator_os;
132 uint32_t rev_level;
133 uint16_t def_resuid;
134 uint16_t def_resgid;
135 uint32_t first_ino;
136 uint16_t inode_size;
137 uint16_t block_group_nr;
138 uint32_t feature_compat;
139 uint32_t feature_incompat;
140 uint32_t feature_ro_compat;
141 uint8_t uuid[16];
142 char volume_name[16];
143 char last_mounted[64];
144 uint32_t algorithm_usage_bitmap;
145 uint8_t prealloc_blocks;
146 uint8_t prealloc_dir_blocks;
147 uint16_t padding;
148
149 union {
150 struct {
151 uint32_t journal_uuid[4];
152 uint32_t journal_inum;
153 uint32_t journal_dev;
154 uint32_t last_orphan;
155 uint32_t hash_seed[4];
156 uint8_t def_hash_version;
157 uint8_t journal_backup_type;
158 uint16_t desc_size;
159 uint32_t default_mount_opts;
160 uint32_t first_meta_bg;
161 uint32_t mkfs_time;
162 uint32_t journal_blocks[17];
163 uint32_t quota_group_inode; // [4] → offset 0x258
164 uint32_t quota_project_inode; // [5] → offset 0x25C
165 };
166 uint32_t reserved[204];
167 };
168} __packed;
169
170struct ext2_group_desc {
171 uint32_t block_bitmap;
172 uint32_t inode_bitmap;
173 uint32_t inode_table;
174 uint16_t free_blocks_count;
175 uint16_t free_inodes_count;
176 uint16_t used_dirs_count;
177 uint16_t pad;
178 uint32_t reserved[3];
179} __attribute__((__packed__));
180
181struct ext2_inode {
182 mode_t mode;
183 uint16_t uid;
184 uint32_t size;
185 uint32_t atime;
186 uint32_t ctime;
187 uint32_t mtime;
188 uint32_t dtime;
189 uint16_t gid;
190 uint16_t links_count;
191 uint32_t blocks;
192 uint32_t flags;
193 uint32_t osd1;
194
195 uint32_t block[EXT2_NBLOCKS];
196 uint32_t generation;
197 uint32_t file_acl;
198 uint32_t dir_acl;
199 uint32_t faddr;
200 uint8_t frag[16];
201 uint8_t osd2[12];
202};
203
204struct ext2_full_inode {
205 struct ext2_inode node;
206 inode_t inode_num;
207 struct bcache_entry *ent;
208};
209
210struct ext2_dir_entry {
211 inode_t inode;
212 uint16_t rec_len;
213 uint8_t name_len;
214 uint8_t file_type;
215 char name[EXT2_NAME_LEN + 1];
216} __packed;
217
218struct ext2_fs {
219 struct partition *partition;
220 struct block_device *drive;
221 struct ext2_sblock *sblock;
222 struct ext2_group_desc *group_desc;
223 struct bcache_entry *sbcache_ent;
224 struct bcache_entry *gdesc_cache_ent;
225 uint32_t num_groups;
226 uint32_t inodes_count;
227 uint32_t inodes_per_group;
228 uint32_t blocks_per_group;
229 uint32_t block_size;
230 uint32_t sectors_per_block;
231 uint16_t inode_size;
232
233 /* lock the fs struct */
234 struct spinlock lock;
235};
236
237typedef bool (*dir_entry_callback)(struct ext2_fs *fs,
238 struct ext2_dir_entry *entry, void *ctx,
239 uint32_t block_num, uint32_t entry_num,
240 uint32_t entry_offset);
241
242typedef void (*ext2_block_visitor)(struct ext2_fs *fs, struct ext2_inode *inode,
243 uint32_t depth, uint32_t *block_ptr,
244 void *user_data);
245
246//
247//
248// R/W + Mount
249//
250//
251
252uint8_t *ext2_block_read(struct ext2_fs *fs, uint32_t block_num,
253 struct bcache_entry **out);
254
255bool ext2_block_write(struct ext2_fs *fs, struct bcache_entry *ent,
256 enum bio_request_priority prio);
257
258bool ext2_read_superblock(struct partition *, struct ext2_sblock *sblock);
259
260bool ext2_write_superblock(struct ext2_fs *fs);
261bool ext2_write_group_desc(struct ext2_fs *fs);
262
263enum errno ext2_mount(struct partition *, struct ext2_fs *fs,
264 struct ext2_sblock *sblock, struct vfs_node *out_node);
265
266struct vfs_node *ext2_g_mount(struct partition *);
267
268struct ext2_inode *ext2_inode_read(struct ext2_fs *fs, inode_t inode_idx,
269 struct bcache_entry **out_ent);
270
271bool ext2_inode_write(struct ext2_fs *fs, inode_t inode_num,
272 const struct ext2_inode *inode);
273
274uint32_t ext2_get_or_set_block(struct ext2_fs *fs, struct ext2_inode *inode,
275 uint32_t block_index, uint32_t new_block_num,
276 bool allocate, bool *was_allocated);
277
278//
279//
280// Util
281//
282//
283
284uint32_t ext2_block_to_lba(struct ext2_fs *fs, uint32_t block_num);
285bool ext2_dirent_valid(struct ext2_dir_entry *entry);
286void ext2_init_inode(struct ext2_inode *new_inode, mode_t mode);
287
288void ext2_init_dirent(struct ext2_fs *fs, struct ext2_dir_entry *new_entry,
289 inode_t inode_num, const char *name, uint8_t type);
290
291uint8_t ext2_extract_ftype(mode_t mode);
292
293bool ext2_walk_dir(struct ext2_fs *fs, struct ext2_full_inode *dir,
294 dir_entry_callback cb, void *ctx);
295
296static inline void ext2_dealloc_inode(struct ext2_full_inode *ino) {
297 kfree(ino);
298}
299
300static inline uint32_t ext2_get_block_group(struct ext2_fs *fs,
301 uint32_t block) {
302 return (block - 1) / fs->sblock->blocks_per_group;
303}
304
305static inline uint32_t ext2_get_inode_group(struct ext2_fs *fs, inode_t inode) {
306 return (inode - 1) / fs->inodes_per_group;
307}
308
309static inline enum irql ext2_fs_lock(struct ext2_fs *fs) {
310 return spin_lock(lock: &fs->lock);
311}
312
313static inline void ext2_fs_unlock(struct ext2_fs *fs, enum irql i) {
314 spin_unlock(lock: &fs->lock, old: i);
315}
316
317static inline void ext2_prefetch_block(struct ext2_fs *fs, uint32_t block) {
318 uint32_t lba = ext2_block_to_lba(fs, block_num: block);
319 bcache_prefetch_async(disk: fs->drive, lba, block_size: fs->block_size,
320 spb: fs->sectors_per_block);
321}
322
323static inline void ext2_inode_lock(struct ext2_full_inode *ino) {
324 bcache_ent_lock(ent: ino->ent);
325}
326
327static inline void ext2_inode_unlock(struct ext2_full_inode *ino) {
328 bcache_ent_unlock(ent: ino->ent);
329}
330
331static inline uint8_t *ext2_create_bcache_ent(struct ext2_fs *fs,
332 uint32_t block,
333 struct bcache_entry **out) {
334 return bcache_create_ent(disk: fs->drive, lba: ext2_block_to_lba(fs, block_num: block),
335 block_size: fs->block_size, sectors_per_block: fs->sectors_per_block, false, out_entry: out);
336}
337
338//
339//
340// Higher level stuff
341//
342//
343
344enum errno ext2_link_file(struct ext2_fs *fs, struct ext2_full_inode *dir_inode,
345 struct ext2_full_inode *inode, const char *name,
346 uint8_t type, bool increment_links);
347
348enum errno ext2_unlink_file(struct ext2_fs *fs,
349 struct ext2_full_inode *dir_inode, const char *name,
350 bool free_blocks, bool decrement_links);
351
352enum errno ext2_create_file(struct ext2_fs *fs,
353 struct ext2_full_inode *parent_dir,
354 const char *name, mode_t mode,
355 bool increment_links);
356
357enum errno ext2_symlink_file(struct ext2_fs *fs,
358 struct ext2_full_inode *dir_inode,
359 const char *name, const char *target);
360
361enum errno ext2_write_file(struct ext2_fs *fs, struct ext2_full_inode *inode,
362 uint32_t offset, const uint8_t *src, uint32_t size);
363
364enum errno ext2_read_file(struct ext2_fs *fs, struct ext2_full_inode *inode,
365 uint32_t offset, uint8_t *buffer, uint64_t length);
366
367enum errno ext2_truncate_file(struct ext2_fs *fs, struct ext2_full_inode *inode,
368 uint32_t new_size);
369
370enum errno ext2_chmod(struct ext2_fs *fs, struct ext2_full_inode *node,
371 mode_t new_mode);
372
373enum errno ext2_chown(struct ext2_fs *fs, struct ext2_full_inode *node,
374 uid_t new_uid, gid_t new_gid);
375
376enum errno ext2_readlink(struct ext2_fs *fs, struct ext2_full_inode *node,
377 char *buf, uint64_t size);
378
379struct ext2_full_inode *ext2_find_file_in_dir(struct ext2_fs *fs,
380 struct ext2_full_inode *dir_inode,
381 const char *fname,
382 uint8_t *type_out);
383
384bool ext2_dir_contains_file(struct ext2_fs *fs,
385 struct ext2_full_inode *dir_inode,
386 const char *fname);
387
388enum errno ext2_mkdir(struct ext2_fs *fs, struct ext2_full_inode *parent_dir,
389 const char *name, mode_t mode);
390
391enum errno ext2_rmdir(struct ext2_fs *fs, struct ext2_full_inode *parent_dir,
392 const char *name);
393
394enum errno ext2_readdir(struct ext2_fs *fs, struct ext2_full_inode *dir_inode,
395 struct ext2_dir_entry *out, uint32_t entry_offset);
396
397//
398//
399//
400// Alloc/dealloc
401//
402//
403
404uint32_t ext2_alloc_block(struct ext2_fs *fs);
405bool ext2_free_block(struct ext2_fs *fs, uint32_t block_num);
406inode_t ext2_alloc_inode(struct ext2_fs *fs);
407bool ext2_free_inode(struct ext2_fs *fs, inode_t inode_num);
408
409bool ext2_find_first_available(struct ext2_fs *fs, struct ext2_full_inode *dir,
410 uint32_t *new_block);
411
412void ext2_traverse_inode_blocks(struct ext2_fs *fs, struct ext2_inode *inode,
413 ext2_block_visitor visitor, void *user_data,
414 bool readahead);
415
416void ext2_g_print(struct partition *);
417
418void ext2_dump_file_data(struct ext2_fs *fs, const struct ext2_inode *inode,
419 uint32_t start_block_index, uint32_t length);
420
421#pragma once
422