1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2011 - 2012 Samsung Electronics
4  * EXT4 filesystem implementation in Uboot by
5  * Uma Shankar <uma.shankar@samsung.com>
6  * Manjunatha C Achar <a.manjunatha@samsung.com>
7  *
8  * ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
9  *		       Ext4 read optimization taken from Open-Moko
10  *		       Qi bootloader
11  *
12  * (C) Copyright 2004
13  * esd gmbh <www.esd-electronics.com>
14  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
15  *
16  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
17  * GRUB  --  GRand Unified Bootloader
18  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
19  *
20  * ext4write : Based on generic ext4 protocol.
21  */
22 
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 
33 int ext4fs_symlinknest;
34 struct ext_filesystem ext_fs;
35 
get_fs(void)36 struct ext_filesystem *get_fs(void)
37 {
38 	return &ext_fs;
39 }
40 
ext4fs_free_node(struct ext2fs_node * node,struct ext2fs_node * currroot)41 void 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  * Taken from openmoko-kernel mailing list: By Andy green
49  * Optimized read file API : collects and defers contiguous sector
50  * reads into one potentially more efficient larger sequential read action
51  */
ext4fs_read_file(struct ext2fs_node * node,loff_t pos,loff_t len,char * buf,loff_t * actread)52 int 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 	/* Adjust len so it we can't read past the end of the file. */
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 		/* Last block.  */
99 		if (i == blockcnt - 1) {
100 			blockend = (len + pos) - (blocksize * i);
101 
102 			/* The last portion is exactly blocksize. */
103 			if (!blockend)
104 				blockend = blocksize;
105 		}
106 
107 		/* First block. */
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 {	/* spill */
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 				/* spill */
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 			/* Zero no more than `len' bytes. */
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 		/* spill */
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 
ext4fs_ls(const char * dirname)186 int 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 
ext4fs_exists(const char * filename)209 int 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 
ext4fs_size(const char * filename,loff_t * size)218 int ext4fs_size(const char *filename, loff_t *size)
219 {
220 	return ext4fs_open(filename, size);
221 }
222 
ext4fs_read(char * buf,loff_t offset,loff_t len,loff_t * actread)223 int 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 
ext4fs_probe(struct blk_desc * fs_dev_desc,struct disk_partition * fs_partition)231 int 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 
ext4_read_file(const char * filename,void * buf,loff_t offset,loff_t len,loff_t * len_read)244 int 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 
ext4fs_uuid(char * uuid_str)262 int 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 
ext_cache_init(struct ext_block_cache * cache)277 void ext_cache_init(struct ext_block_cache *cache)
278 {
279 	memset(cache, 0, sizeof(*cache));
280 }
281 
ext_cache_fini(struct ext_block_cache * cache)282 void ext_cache_fini(struct ext_block_cache *cache)
283 {
284 	free(cache->buf);
285 	ext_cache_init(cache);
286 }
287 
ext_cache_read(struct ext_block_cache * cache,lbaint_t block,int size)288 int ext_cache_read(struct ext_block_cache *cache, lbaint_t block, int size)
289 {
290 	/* This could be more lenient, but this is simple and enough for now */
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