xref: /openbmc/u-boot/fs/ext4/ext4fs.c (revision e47b2d67)
1 /*
2  * (C) Copyright 2011 - 2012 Samsung Electronics
3  * EXT4 filesystem implementation in Uboot by
4  * Uma Shankar <uma.shankar@samsung.com>
5  * Manjunatha C Achar <a.manjunatha@samsung.com>
6  *
7  * ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
8  *		       Ext4 read optimization taken from Open-Moko
9  *		       Qi bootloader
10  *
11  * (C) Copyright 2004
12  * esd gmbh <www.esd-electronics.com>
13  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
14  *
15  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
16  * GRUB  --  GRand Unified Bootloader
17  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
18  *
19  * ext4write : Based on generic ext4 protocol.
20  *
21  * SPDX-License-Identifier:	GPL-2.0+
22  */
23 
24 #include <common.h>
25 #include <ext_common.h>
26 #include <ext4fs.h>
27 #include "ext4_common.h"
28 #include <div64.h>
29 
30 int ext4fs_symlinknest;
31 struct ext_filesystem ext_fs;
32 
33 struct ext_filesystem *get_fs(void)
34 {
35 	return &ext_fs;
36 }
37 
38 void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
39 {
40 	if ((node != &ext4fs_root->diropen) && (node != currroot))
41 		free(node);
42 }
43 
44 /*
45  * Taken from openmoko-kernel mailing list: By Andy green
46  * Optimized read file API : collects and defers contiguous sector
47  * reads into one potentially more efficient larger sequential read action
48  */
49 int ext4fs_read_file(struct ext2fs_node *node, loff_t pos,
50 		loff_t len, char *buf, loff_t *actread)
51 {
52 	struct ext_filesystem *fs = get_fs();
53 	int i;
54 	lbaint_t blockcnt;
55 	int log2blksz = fs->dev_desc->log2blksz;
56 	int log2_fs_blocksize = LOG2_BLOCK_SIZE(node->data) - log2blksz;
57 	int blocksize = (1 << (log2_fs_blocksize + log2blksz));
58 	unsigned int filesize = le32_to_cpu(node->inode.size);
59 	lbaint_t previous_block_number = -1;
60 	lbaint_t delayed_start = 0;
61 	lbaint_t delayed_extent = 0;
62 	lbaint_t delayed_skipfirst = 0;
63 	lbaint_t delayed_next = 0;
64 	char *delayed_buf = NULL;
65 	short status;
66 
67 	/* Adjust len so it we can't read past the end of the file. */
68 	if (len + pos > filesize)
69 		len = (filesize - pos);
70 
71 	blockcnt = lldiv(((len + pos) + blocksize - 1), blocksize);
72 
73 	for (i = lldiv(pos, blocksize); i < blockcnt; i++) {
74 		lbaint_t blknr;
75 		int blockoff = pos - (blocksize * i);
76 		int blockend = blocksize;
77 		int skipfirst = 0;
78 		blknr = read_allocated_block(&(node->inode), i);
79 		if (blknr < 0)
80 			return -1;
81 
82 		blknr = blknr << log2_fs_blocksize;
83 
84 		/* Last block.  */
85 		if (i == blockcnt - 1) {
86 			blockend = (len + pos) - (blocksize * i);
87 
88 			/* The last portion is exactly blocksize. */
89 			if (!blockend)
90 				blockend = blocksize;
91 		}
92 
93 		/* First block. */
94 		if (i == lldiv(pos, blocksize)) {
95 			skipfirst = blockoff;
96 			blockend -= skipfirst;
97 		}
98 		if (blknr) {
99 			int status;
100 
101 			if (previous_block_number != -1) {
102 				if (delayed_next == blknr) {
103 					delayed_extent += blockend;
104 					delayed_next += blockend >> log2blksz;
105 				} else {	/* spill */
106 					status = ext4fs_devread(delayed_start,
107 							delayed_skipfirst,
108 							delayed_extent,
109 							delayed_buf);
110 					if (status == 0)
111 						return -1;
112 					previous_block_number = blknr;
113 					delayed_start = blknr;
114 					delayed_extent = blockend;
115 					delayed_skipfirst = skipfirst;
116 					delayed_buf = buf;
117 					delayed_next = blknr +
118 						(blockend >> log2blksz);
119 				}
120 			} else {
121 				previous_block_number = blknr;
122 				delayed_start = blknr;
123 				delayed_extent = blockend;
124 				delayed_skipfirst = skipfirst;
125 				delayed_buf = buf;
126 				delayed_next = blknr +
127 					(blockend >> log2blksz);
128 			}
129 		} else {
130 			if (previous_block_number != -1) {
131 				/* spill */
132 				status = ext4fs_devread(delayed_start,
133 							delayed_skipfirst,
134 							delayed_extent,
135 							delayed_buf);
136 				if (status == 0)
137 					return -1;
138 				previous_block_number = -1;
139 			}
140 			memset(buf, 0, blocksize - skipfirst);
141 		}
142 		buf += blocksize - skipfirst;
143 	}
144 	if (previous_block_number != -1) {
145 		/* spill */
146 		status = ext4fs_devread(delayed_start,
147 					delayed_skipfirst, delayed_extent,
148 					delayed_buf);
149 		if (status == 0)
150 			return -1;
151 		previous_block_number = -1;
152 	}
153 
154 	*actread  = len;
155 	return 0;
156 }
157 
158 int ext4fs_ls(const char *dirname)
159 {
160 	struct ext2fs_node *dirnode;
161 	int status;
162 
163 	if (dirname == NULL)
164 		return 0;
165 
166 	status = ext4fs_find_file(dirname, &ext4fs_root->diropen, &dirnode,
167 				  FILETYPE_DIRECTORY);
168 	if (status != 1) {
169 		printf("** Can not find directory. **\n");
170 		return 1;
171 	}
172 
173 	ext4fs_iterate_dir(dirnode, NULL, NULL, NULL);
174 	ext4fs_free_node(dirnode, &ext4fs_root->diropen);
175 
176 	return 0;
177 }
178 
179 int ext4fs_exists(const char *filename)
180 {
181 	loff_t file_len;
182 	int ret;
183 
184 	ret = ext4fs_open(filename, &file_len);
185 	return ret == 0;
186 }
187 
188 int ext4fs_size(const char *filename, loff_t *size)
189 {
190 	return ext4fs_open(filename, size);
191 }
192 
193 int ext4fs_read(char *buf, loff_t offset, loff_t len, loff_t *actread)
194 {
195 	if (ext4fs_root == NULL || ext4fs_file == NULL)
196 		return -1;
197 
198 	return ext4fs_read_file(ext4fs_file, offset, len, buf, actread);
199 }
200 
201 int ext4fs_probe(struct blk_desc *fs_dev_desc,
202 		 disk_partition_t *fs_partition)
203 {
204 	ext4fs_set_blk_dev(fs_dev_desc, fs_partition);
205 
206 	if (!ext4fs_mount(fs_partition->size)) {
207 		ext4fs_close();
208 		return -1;
209 	}
210 
211 	return 0;
212 }
213 
214 int ext4_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
215 		   loff_t *len_read)
216 {
217 	loff_t file_len;
218 	int ret;
219 
220 	ret = ext4fs_open(filename, &file_len);
221 	if (ret < 0) {
222 		printf("** File not found %s **\n", filename);
223 		return -1;
224 	}
225 
226 	if (len == 0)
227 		len = file_len;
228 
229 	return ext4fs_read(buf, offset, len, len_read);
230 }
231 
232 int ext4fs_uuid(char *uuid_str)
233 {
234 	if (ext4fs_root == NULL)
235 		return -1;
236 
237 #ifdef CONFIG_LIB_UUID
238 	uuid_bin_to_str((unsigned char *)ext4fs_root->sblock.unique_id,
239 			uuid_str, UUID_STR_FORMAT_STD);
240 
241 	return 0;
242 #else
243 	return -ENOSYS;
244 #endif
245 }
246