xref: /openbmc/u-boot/fs/ext4/dev.c (revision ea818dbb)
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  * made from existing ext2/dev.c file of Uboot
8  * (C) Copyright 2004
9  * esd gmbh <www.esd-electronics.com>
10  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
11  *
12  * based on code of fs/reiserfs/dev.c by
13  *
14  * (C) Copyright 2003 - 2004
15  * Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
16  *
17  * This program is free software; you can redistribute it and/or modify
18  * it under the terms of the GNU General Public License as published by
19  * the Free Software Foundation; either version 2 of the License, or
20  * (at your option) any later version.
21  *
22  * This program is distributed in the hope that it will be useful,
23  * but WITHOUT ANY WARRANTY; without even the implied warranty of
24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25  * GNU General Public License for more details.
26  *
27  * You should have received a copy of the GNU General Public License
28  * along with this program; if not, write to the Free Software
29  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
30  *
31  */
32 
33 /*
34  * Changelog:
35  *	0.1 - Newly created file for ext4fs support. Taken from
36  *		fs/ext2/dev.c file in uboot.
37  */
38 
39 #include <common.h>
40 #include <config.h>
41 #include <ext4fs.h>
42 #include <ext_common.h>
43 #include "ext4_common.h"
44 
45 lbaint_t part_offset;
46 
47 static block_dev_desc_t *ext4fs_block_dev_desc;
48 static disk_partition_t *part_info;
49 
50 void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info)
51 {
52 	assert(rbdd->blksz == (1 << rbdd->log2blksz));
53 	ext4fs_block_dev_desc = rbdd;
54 	get_fs()->dev_desc = rbdd;
55 	part_info = info;
56 	part_offset = info->start;
57 	get_fs()->total_sect = (info->size * info->blksz) >>
58 		get_fs()->dev_desc->log2blksz;
59 }
60 
61 int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf)
62 {
63 	unsigned block_len;
64 	int log2blksz = ext4fs_block_dev_desc->log2blksz;
65 	ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (ext4fs_block_dev_desc ?
66 						 ext4fs_block_dev_desc->blksz :
67 						 0));
68 	if (ext4fs_block_dev_desc == NULL) {
69 		printf("** Invalid Block Device Descriptor (NULL)\n");
70 		return 0;
71 	}
72 
73 	/* Check partition boundaries */
74 	if ((sector < 0) ||
75 	    ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
76 	     >= part_info->size)) {
77 		printf("%s read outside partition " LBAFU "\n", __func__,
78 		       sector);
79 		return 0;
80 	}
81 
82 	/* Get the read to the beginning of a partition */
83 	sector += byte_offset >> log2blksz;
84 	byte_offset &= ext4fs_block_dev_desc->blksz - 1;
85 
86 	debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);
87 
88 	if (byte_offset != 0) {
89 		/* read first part which isn't aligned with start of sector */
90 		if (ext4fs_block_dev_desc->
91 		    block_read(ext4fs_block_dev_desc->dev,
92 				part_info->start + sector, 1,
93 				(unsigned long *) sec_buf) != 1) {
94 			printf(" ** ext2fs_devread() read error **\n");
95 			return 0;
96 		}
97 		memcpy(buf, sec_buf + byte_offset,
98 			min(ext4fs_block_dev_desc->blksz
99 			    - byte_offset, byte_len));
100 		buf += min(ext4fs_block_dev_desc->blksz
101 			   - byte_offset, byte_len);
102 		byte_len -= min(ext4fs_block_dev_desc->blksz
103 				- byte_offset, byte_len);
104 		sector++;
105 	}
106 
107 	if (byte_len == 0)
108 		return 1;
109 
110 	/* read sector aligned part */
111 	block_len = byte_len & ~(ext4fs_block_dev_desc->blksz - 1);
112 
113 	if (block_len == 0) {
114 		ALLOC_CACHE_ALIGN_BUFFER(u8, p, ext4fs_block_dev_desc->blksz);
115 
116 		block_len = ext4fs_block_dev_desc->blksz;
117 		ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
118 						  part_info->start + sector,
119 						  1, (unsigned long *)p);
120 		memcpy(buf, p, byte_len);
121 		return 1;
122 	}
123 
124 	if (ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
125 					       part_info->start + sector,
126 					       block_len >> log2blksz,
127 					       (unsigned long *) buf) !=
128 					       block_len >> log2blksz) {
129 		printf(" ** %s read error - block\n", __func__);
130 		return 0;
131 	}
132 	block_len = byte_len & ~(ext4fs_block_dev_desc->blksz - 1);
133 	buf += block_len;
134 	byte_len -= block_len;
135 	sector += block_len / ext4fs_block_dev_desc->blksz;
136 
137 	if (byte_len != 0) {
138 		/* read rest of data which are not in whole sector */
139 		if (ext4fs_block_dev_desc->
140 		    block_read(ext4fs_block_dev_desc->dev,
141 				part_info->start + sector, 1,
142 				(unsigned long *) sec_buf) != 1) {
143 			printf("* %s read error - last part\n", __func__);
144 			return 0;
145 		}
146 		memcpy(buf, sec_buf, byte_len);
147 	}
148 	return 1;
149 }
150 
151 int ext4_read_superblock(char *buffer)
152 {
153 	struct ext_filesystem *fs = get_fs();
154 	int sect = SUPERBLOCK_START >> fs->dev_desc->log2blksz;
155 	int off = SUPERBLOCK_START % fs->dev_desc->blksz;
156 
157 	return ext4fs_devread(sect, off, SUPERBLOCK_SIZE,
158 				buffer);
159 }
160