1 /* SPDX-License-Identifier: GPL-2.0+ OR Apache-2.0 */
2 /*
3 * Copyright (C) 2019 HUAWEI, Inc.
4 * http://www.huawei.com/
5 * Created by Gao Xiang <gaoxiang25@huawei.com>
6 */
7 #ifndef __EROFS_INTERNAL_H
8 #define __EROFS_INTERNAL_H
9
10 #ifdef __cplusplus
11 extern "C"
12 {
13 #endif
14
15 #include "list.h"
16 #include "err.h"
17
18 typedef unsigned short umode_t;
19
20 #define __packed __attribute__((__packed__))
21
22 #include "erofs_fs.h"
23 #include <fcntl.h>
24
25 #ifndef PATH_MAX
26 #define PATH_MAX 4096 /* # chars in a path name including nul */
27 #endif
28
29 #ifndef PAGE_SHIFT
30 #define PAGE_SHIFT (12)
31 #endif
32
33 #ifndef PAGE_SIZE
34 #define PAGE_SIZE (1U << PAGE_SHIFT)
35 #endif
36
37 /* no obvious reason to support explicit PAGE_SIZE != 4096 for now */
38 #if PAGE_SIZE != 4096
39 #warning EROFS may be incompatible on your platform
40 #endif
41
42 #ifndef PAGE_MASK
43 #define PAGE_MASK (~(PAGE_SIZE-1))
44 #endif
45
46 #define LOG_BLOCK_SIZE (12)
47 #define EROFS_BLKSIZ (1U << LOG_BLOCK_SIZE)
48
49 #define EROFS_ISLOTBITS 5
50 #define EROFS_SLOTSIZE (1U << EROFS_ISLOTBITS)
51
52 typedef u64 erofs_off_t;
53 typedef u64 erofs_nid_t;
54 /* data type for filesystem-wide blocks number */
55 typedef u32 erofs_blk_t;
56
57 #define NULL_ADDR ((unsigned int)-1)
58 #define NULL_ADDR_UL ((unsigned long)-1)
59
60 #define erofs_blknr(addr) ((addr) / EROFS_BLKSIZ)
61 #define erofs_blkoff(addr) ((addr) % EROFS_BLKSIZ)
62 #define blknr_to_addr(nr) ((erofs_off_t)(nr) * EROFS_BLKSIZ)
63
64 #define BLK_ROUND_UP(addr) DIV_ROUND_UP(addr, EROFS_BLKSIZ)
65
66 struct erofs_buffer_head;
67
68 struct erofs_device_info {
69 u32 blocks;
70 u32 mapped_blkaddr;
71 };
72
73 struct erofs_sb_info {
74 struct erofs_device_info *devs;
75
76 u64 total_blocks;
77 u64 primarydevice_blocks;
78
79 erofs_blk_t meta_blkaddr;
80 erofs_blk_t xattr_blkaddr;
81
82 u32 feature_compat;
83 u32 feature_incompat;
84 u64 build_time;
85 u32 build_time_nsec;
86
87 unsigned char islotbits;
88
89 /* what we really care is nid, rather than ino.. */
90 erofs_nid_t root_nid;
91 /* used for statfs, f_files - f_favail */
92 u64 inos;
93
94 u8 uuid[16];
95
96 u16 available_compr_algs;
97 u16 lz4_max_distance;
98
99 u32 checksum;
100 u16 extra_devices;
101 union {
102 u16 devt_slotoff; /* used for mkfs */
103 u16 device_id_mask; /* used for others */
104 };
105 };
106
107 /* global sbi */
108 extern struct erofs_sb_info sbi;
109
iloc(erofs_nid_t nid)110 static inline erofs_off_t iloc(erofs_nid_t nid)
111 {
112 return blknr_to_addr(sbi.meta_blkaddr) + (nid << sbi.islotbits);
113 }
114
115 #define EROFS_FEATURE_FUNCS(name, compat, feature) \
116 static inline bool erofs_sb_has_##name(void) \
117 { \
118 return sbi.feature_##compat & EROFS_FEATURE_##feature; \
119 } \
120 static inline void erofs_sb_set_##name(void) \
121 { \
122 sbi.feature_##compat |= EROFS_FEATURE_##feature; \
123 } \
124 static inline void erofs_sb_clear_##name(void) \
125 { \
126 sbi.feature_##compat &= ~EROFS_FEATURE_##feature; \
127 }
128
129 EROFS_FEATURE_FUNCS(lz4_0padding, incompat, INCOMPAT_LZ4_0PADDING)
130 EROFS_FEATURE_FUNCS(compr_cfgs, incompat, INCOMPAT_COMPR_CFGS)
131 EROFS_FEATURE_FUNCS(big_pcluster, incompat, INCOMPAT_BIG_PCLUSTER)
132 EROFS_FEATURE_FUNCS(chunked_file, incompat, INCOMPAT_CHUNKED_FILE)
133 EROFS_FEATURE_FUNCS(device_table, incompat, INCOMPAT_DEVICE_TABLE)
134 EROFS_FEATURE_FUNCS(ztailpacking, incompat, INCOMPAT_ZTAILPACKING)
135 EROFS_FEATURE_FUNCS(sb_chksum, compat, COMPAT_SB_CHKSUM)
136
137 #define EROFS_I_EA_INITED (1 << 0)
138 #define EROFS_I_Z_INITED (1 << 1)
139
140 struct erofs_inode {
141 struct list_head i_hash, i_subdirs, i_xattrs;
142
143 union {
144 /* (erofsfuse) runtime flags */
145 unsigned int flags;
146 /* (mkfs.erofs) device ID containing source file */
147 u32 dev;
148 };
149 unsigned int i_count;
150 struct erofs_inode *i_parent;
151
152 umode_t i_mode;
153 erofs_off_t i_size;
154
155 u64 i_ino[2];
156 u32 i_uid;
157 u32 i_gid;
158 u64 i_mtime;
159 u32 i_mtime_nsec;
160 u32 i_nlink;
161
162 union {
163 u32 i_blkaddr;
164 u32 i_blocks;
165 u32 i_rdev;
166 struct {
167 unsigned short chunkformat;
168 unsigned char chunkbits;
169 };
170 } u;
171
172 char i_srcpath[PATH_MAX + 1];
173
174 unsigned char datalayout;
175 unsigned char inode_isize;
176 /* inline tail-end packing size */
177 unsigned short idata_size;
178 bool compressed_idata;
179
180 unsigned int xattr_isize;
181 unsigned int extent_isize;
182
183 erofs_nid_t nid;
184 struct erofs_buffer_head *bh;
185 struct erofs_buffer_head *bh_inline, *bh_data;
186
187 void *idata;
188
189 /* (ztailpacking) in order to recover uncompressed EOF data */
190 void *eof_tailraw;
191 unsigned int eof_tailrawsize;
192
193 union {
194 void *compressmeta;
195 void *chunkindexes;
196 struct {
197 uint16_t z_advise;
198 uint8_t z_algorithmtype[2];
199 uint8_t z_logical_clusterbits;
200 uint8_t z_physical_clusterblks;
201 uint64_t z_tailextent_headlcn;
202 unsigned int z_idataoff;
203 #define z_idata_size idata_size
204 };
205 };
206 #ifdef WITH_ANDROID
207 uint64_t capabilities;
208 #endif
209 };
210
is_inode_layout_compression(struct erofs_inode * inode)211 static inline bool is_inode_layout_compression(struct erofs_inode *inode)
212 {
213 return erofs_inode_is_data_compressed(inode->datalayout);
214 }
215
erofs_bitrange(unsigned int value,unsigned int bit,unsigned int bits)216 static inline unsigned int erofs_bitrange(unsigned int value, unsigned int bit,
217 unsigned int bits)
218 {
219 return (value >> bit) & ((1 << bits) - 1);
220 }
221
erofs_inode_version(unsigned int value)222 static inline unsigned int erofs_inode_version(unsigned int value)
223 {
224 return erofs_bitrange(value, EROFS_I_VERSION_BIT,
225 EROFS_I_VERSION_BITS);
226 }
227
erofs_inode_datalayout(unsigned int value)228 static inline unsigned int erofs_inode_datalayout(unsigned int value)
229 {
230 return erofs_bitrange(value, EROFS_I_DATALAYOUT_BIT,
231 EROFS_I_DATALAYOUT_BITS);
232 }
233
234 #define IS_ROOT(x) ((x) == (x)->i_parent)
235
236 struct erofs_dentry {
237 struct list_head d_child; /* child of parent list */
238
239 unsigned int type;
240 char name[EROFS_NAME_LEN];
241 union {
242 struct erofs_inode *inode;
243 erofs_nid_t nid;
244 };
245 };
246
is_dot_dotdot_len(const char * name,unsigned int len)247 static inline bool is_dot_dotdot_len(const char *name, unsigned int len)
248 {
249 if (len >= 1 && name[0] != '.')
250 return false;
251
252 return len == 1 || (len == 2 && name[1] == '.');
253 }
254
is_dot_dotdot(const char * name)255 static inline bool is_dot_dotdot(const char *name)
256 {
257 if (name[0] != '.')
258 return false;
259
260 return name[1] == '\0' || (name[1] == '.' && name[2] == '\0');
261 }
262
263 #include <stdio.h>
264 #include <string.h>
265
erofs_strerror(int err)266 static inline const char *erofs_strerror(int err)
267 {
268 static char msg[256];
269
270 sprintf(msg, "[Error %d] %s", -err, strerror(-err));
271 return msg;
272 }
273
274 enum {
275 BH_Meta,
276 BH_Mapped,
277 BH_Encoded,
278 BH_FullMapped,
279 };
280
281 /* Has a disk mapping */
282 #define EROFS_MAP_MAPPED (1 << BH_Mapped)
283 /* Located in metadata (could be copied from bd_inode) */
284 #define EROFS_MAP_META (1 << BH_Meta)
285 /* The extent is encoded */
286 #define EROFS_MAP_ENCODED (1 << BH_Encoded)
287 /* The length of extent is full */
288 #define EROFS_MAP_FULL_MAPPED (1 << BH_FullMapped)
289
290 struct erofs_map_blocks {
291 char mpage[EROFS_BLKSIZ];
292
293 erofs_off_t m_pa, m_la;
294 u64 m_plen, m_llen;
295
296 unsigned short m_deviceid;
297 char m_algorithmformat;
298 unsigned int m_flags;
299 erofs_blk_t index;
300 };
301
302 /*
303 * Used to get the exact decompressed length, e.g. fiemap (consider lookback
304 * approach instead if possible since it's more metadata lightweight.)
305 */
306 #define EROFS_GET_BLOCKS_FIEMAP 0x0002
307 #define EROFS_GET_BLOCKS_FINDTAIL 0x0008
308
309 enum {
310 Z_EROFS_COMPRESSION_SHIFTED = Z_EROFS_COMPRESSION_MAX,
311 Z_EROFS_COMPRESSION_RUNTIME_MAX
312 };
313
314 struct erofs_map_dev {
315 erofs_off_t m_pa;
316 unsigned int m_deviceid;
317 };
318
319 /* super.c */
320 int erofs_read_superblock(void);
321
322 /* namei.c */
323 int erofs_read_inode_from_disk(struct erofs_inode *vi);
324 int erofs_ilookup(const char *path, struct erofs_inode *vi);
325 int erofs_read_inode_from_disk(struct erofs_inode *vi);
326
327 /* data.c */
328 int erofs_pread(struct erofs_inode *inode, char *buf,
329 erofs_off_t count, erofs_off_t offset);
330 int erofs_map_blocks(struct erofs_inode *inode,
331 struct erofs_map_blocks *map, int flags);
332 int erofs_map_dev(struct erofs_sb_info *sbi, struct erofs_map_dev *map);
333
erofs_get_occupied_size(const struct erofs_inode * inode,erofs_off_t * size)334 static inline int erofs_get_occupied_size(const struct erofs_inode *inode,
335 erofs_off_t *size)
336 {
337 *size = 0;
338 switch (inode->datalayout) {
339 case EROFS_INODE_FLAT_INLINE:
340 case EROFS_INODE_FLAT_PLAIN:
341 case EROFS_INODE_CHUNK_BASED:
342 *size = inode->i_size;
343 break;
344 case EROFS_INODE_FLAT_COMPRESSION_LEGACY:
345 case EROFS_INODE_FLAT_COMPRESSION:
346 *size = inode->u.i_blocks * EROFS_BLKSIZ;
347 break;
348 default:
349 return -ENOTSUP;
350 }
351 return 0;
352 }
353
354 /* zmap.c */
355 int z_erofs_fill_inode(struct erofs_inode *vi);
356 int z_erofs_map_blocks_iter(struct erofs_inode *vi,
357 struct erofs_map_blocks *map, int flags);
358
359 #ifdef EUCLEAN
360 #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */
361 #else
362 #define EFSCORRUPTED EIO
363 #endif
364
365 #define CRC32C_POLY_LE 0x82F63B78
erofs_crc32c(u32 crc,const u8 * in,size_t len)366 static inline u32 erofs_crc32c(u32 crc, const u8 *in, size_t len)
367 {
368 int i;
369
370 while (len--) {
371 crc ^= *in++;
372 for (i = 0; i < 8; i++)
373 crc = (crc >> 1) ^ ((crc & 1) ? CRC32C_POLY_LE : 0);
374 }
375 return crc;
376 }
377
378 #ifdef __cplusplus
379 }
380 #endif
381
382 #endif
383