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23#include <common.h>
24#include <blk.h>
25#include <ext_common.h>
26#include <ext4fs.h>
27#include "ext4_common.h"
28#include <div64.h>
29#include <malloc.h>
30#include <part.h>
31#include <uuid.h>
32
33int ext4fs_symlinknest;
34struct ext_filesystem ext_fs;
35
36struct ext_filesystem *get_fs(void)
37{
38 return &ext_fs;
39}
40
41void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
42{
43 if ((node != &ext4fs_root->diropen) && (node != currroot))
44 free(node);
45}
46
47
48
49
50
51
52int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
53 loff_t len, char *buf, loff_t *actread)
54{
55 struct ext_filesystem *fs = get_fs();
56 int i;
57 lbaint_t blockcnt;
58 int log2blksz = fs->dev_desc->log2blksz;
59 int log2_fs_blocksize = LOG2_BLOCK_SIZE(node->data) - log2blksz;
60 int blocksize = (1 << (log2_fs_blocksize + log2blksz));
61 unsigned int filesize = le32_to_cpu(node->inode.size);
62 lbaint_t previous_block_number = -1;
63 lbaint_t delayed_start = 0;
64 lbaint_t delayed_extent = 0;
65 lbaint_t delayed_skipfirst = 0;
66 lbaint_t delayed_next = 0;
67 char *delayed_buf = NULL;
68 char *start_buf = buf;
69 short status;
70 struct ext_block_cache cache;
71
72 ext_cache_init(&cache);
73
74
75 if (len + pos > filesize)
76 len = (filesize - pos);
77
78 if (blocksize <= 0 || len <= 0) {
79 ext_cache_fini(&cache);
80 return -1;
81 }
82
83 blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
84
85 for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
86 long int blknr;
87 int blockoff = pos - (blocksize * i);
88 int blockend = blocksize;
89 int skipfirst = 0;
90 blknr = read_allocated_block(&node->inode, i, &cache);
91 if (blknr < 0) {
92 ext_cache_fini(&cache);
93 return -1;
94 }
95
96 blknr = blknr << log2_fs_blocksize;
97
98
99 if (i == blockcnt - 1) {
100 blockend = (len + pos) - (blocksize * i);
101
102
103 if (!blockend)
104 blockend = blocksize;
105 }
106
107
108 if (i == lldiv(pos, blocksize)) {
109 skipfirst = blockoff;
110 blockend -= skipfirst;
111 }
112 if (blknr) {
113 int status;
114
115 if (previous_block_number != -1) {
116 if (delayed_next == blknr) {
117 delayed_extent += blockend;
118 delayed_next += blockend >> log2blksz;
119 } else {
120 status = ext4fs_devread(delayed_start,
121 delayed_skipfirst,
122 delayed_extent,
123 delayed_buf);
124 if (status == 0) {
125 ext_cache_fini(&cache);
126 return -1;
127 }
128 previous_block_number = blknr;
129 delayed_start = blknr;
130 delayed_extent = blockend;
131 delayed_skipfirst = skipfirst;
132 delayed_buf = buf;
133 delayed_next = blknr +
134 (blockend >> log2blksz);
135 }
136 } else {
137 previous_block_number = blknr;
138 delayed_start = blknr;
139 delayed_extent = blockend;
140 delayed_skipfirst = skipfirst;
141 delayed_buf = buf;
142 delayed_next = blknr +
143 (blockend >> log2blksz);
144 }
145 } else {
146 int n;
147 int n_left;
148 if (previous_block_number != -1) {
149
150 status = ext4fs_devread(delayed_start,
151 delayed_skipfirst,
152 delayed_extent,
153 delayed_buf);
154 if (status == 0) {
155 ext_cache_fini(&cache);
156 return -1;
157 }
158 previous_block_number = -1;
159 }
160
161 n = blocksize - skipfirst;
162 n_left = len - ( buf - start_buf );
163 if (n > n_left)
164 n = n_left;
165 memset(buf, 0, n);
166 }
167 buf += blocksize - skipfirst;
168 }
169 if (previous_block_number != -1) {
170
171 status = ext4fs_devread(delayed_start,
172 delayed_skipfirst, delayed_extent,
173 delayed_buf);
174 if (status == 0) {
175 ext_cache_fini(&cache);
176 return -1;
177 }
178 previous_block_number = -1;
179 }
180
181 *actread = len;
182 ext_cache_fini(&cache);
183 return 0;
184}
185
186int ext4fs_ls(const char *dirname)
187{
188 struct ext2fs_node *dirnode = NULL;
189 int status;
190
191 if (dirname == NULL)
192 return 0;
193
194 status = ext4fs_find_file(dirname, &ext4fs_root->diropen, &dirnode,
195 FILETYPE_DIRECTORY);
196 if (status != 1) {
197 printf("** Can not find directory. **\n");
198 if (dirnode)
199 ext4fs_free_node(dirnode, &ext4fs_root->diropen);
200 return 1;
201 }
202
203 ext4fs_iterate_dir(dirnode, NULL, NULL, NULL);
204 ext4fs_free_node(dirnode, &ext4fs_root->diropen);
205
206 return 0;
207}
208
209int ext4fs_exists(const char *filename)
210{
211 loff_t file_len;
212 int ret;
213
214 ret = ext4fs_open(filename, &file_len);
215 return ret == 0;
216}
217
218int ext4fs_size(const char *filename, loff_t *size)
219{
220 return ext4fs_open(filename, size);
221}
222
223int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
224{
225 if (ext4fs_root == NULL || ext4fs_file == NULL)
226 return -1;
227
228 return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
229}
230
231int ext4fs_probe(struct blk_desc *fs_dev_desc,
232 struct disk_partition *fs_partition)
233{
234 ext4fs_set_blk_dev(fs_dev_desc, fs_partition);
235
236 if (!ext4fs_mount(fs_partition->size)) {
237 ext4fs_close();
238 return -1;
239 }
240
241 return 0;
242}
243
244int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
245 loff_t *len_read)
246{
247 loff_t file_len;
248 int ret;
249
250 ret = ext4fs_open(filename, &file_len);
251 if (ret < 0) {
252 printf("** File not found %s **\n", filename);
253 return -1;
254 }
255
256 if (len == 0)
257 len = file_len;
258
259 return ext4fs_read(buf, offset, len, len_read);
260}
261
262int ext4fs_uuid(char *uuid_str)
263{
264 if (ext4fs_root == NULL)
265 return -1;
266
267#ifdef CONFIG_LIB_UUID
268 uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
269 uuid_str, UUID_STR_FORMAT_STD);
270
271 return 0;
272#else
273 return -ENOSYS;
274#endif
275}
276
277void ext_cache_init(struct ext_block_cache *cache)
278{
279 memset(cache, 0, sizeof(*cache));
280}
281
282void ext_cache_fini(struct ext_block_cache *cache)
283{
284 free(cache->buf);
285 ext_cache_init(cache);
286}
287
288int ext_cache_read(struct ext_block_cache *cache, lbaint_t block, int size)
289{
290
291 if (cache->buf && cache->block == block && cache->size == size)
292 return 1;
293 ext_cache_fini(cache);
294 cache->buf = memalign(ARCH_DMA_MINALIGN, size);
295 if (!cache->buf)
296 return 0;
297 if (!ext4fs_devread(block, 0, size, cache->buf)) {
298 ext_cache_fini(cache);
299 return 0;
300 }
301 cache->block = block;
302 cache->size = size;
303 return 1;
304}
305
