xref: /openbmc/u-boot/fs/ext4/dev.c (revision c9aa831e)
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 
44 unsigned long part_offset;
45 
46 static block_dev_desc_t *ext4fs_block_dev_desc;
47 static disk_partition_t *part_info;
48 
49 void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info)
50 {
51 	ext4fs_block_dev_desc = rbdd;
52 	part_info = info;
53 	part_offset = info->start;
54 	get_fs()->total_sect = (info->size * info->blksz) / SECTOR_SIZE;
55 	get_fs()->dev_desc = rbdd;
56 }
57 
58 int ext4fs_devread(int sector, int byte_offset, int byte_len, char *buf)
59 {
60 	ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, SECTOR_SIZE);
61 	unsigned block_len;
62 
63 	/* Check partition boundaries */
64 	if ((sector < 0)
65 	    || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS)) >=
66 		part_info->size)) {
67 		printf("%s read outside partition %d\n", __func__, sector);
68 		return 0;
69 	}
70 
71 	/* Get the read to the beginning of a partition */
72 	sector += byte_offset >> SECTOR_BITS;
73 	byte_offset &= SECTOR_SIZE - 1;
74 
75 	debug(" <%d, %d, %d>\n", sector, byte_offset, byte_len);
76 
77 	if (ext4fs_block_dev_desc == NULL) {
78 		printf("** Invalid Block Device Descriptor (NULL)\n");
79 		return 0;
80 	}
81 
82 	if (byte_offset != 0) {
83 		/* read first part which isn't aligned with start of sector */
84 		if (ext4fs_block_dev_desc->
85 		    block_read(ext4fs_block_dev_desc->dev,
86 				part_info->start + sector, 1,
87 				(unsigned long *) sec_buf) != 1) {
88 			printf(" ** ext2fs_devread() read error **\n");
89 			return 0;
90 		}
91 		memcpy(buf, sec_buf + byte_offset,
92 			min(SECTOR_SIZE - byte_offset, byte_len));
93 		buf += min(SECTOR_SIZE - byte_offset, byte_len);
94 		byte_len -= min(SECTOR_SIZE - byte_offset, byte_len);
95 		sector++;
96 	}
97 
98 	if (byte_len == 0)
99 		return 1;
100 
101 	/* read sector aligned part */
102 	block_len = byte_len & ~(SECTOR_SIZE - 1);
103 
104 	if (block_len == 0) {
105 		ALLOC_CACHE_ALIGN_BUFFER(u8, p, SECTOR_SIZE);
106 
107 		block_len = SECTOR_SIZE;
108 		ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
109 						  part_info->start + sector,
110 						  1, (unsigned long *)p);
111 		memcpy(buf, p, byte_len);
112 		return 1;
113 	}
114 
115 	if (ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
116 					       part_info->start + sector,
117 					       block_len / SECTOR_SIZE,
118 					       (unsigned long *) buf) !=
119 					       block_len / SECTOR_SIZE) {
120 		printf(" ** %s read error - block\n", __func__);
121 		return 0;
122 	}
123 	block_len = byte_len & ~(SECTOR_SIZE - 1);
124 	buf += block_len;
125 	byte_len -= block_len;
126 	sector += block_len / SECTOR_SIZE;
127 
128 	if (byte_len != 0) {
129 		/* read rest of data which are not in whole sector */
130 		if (ext4fs_block_dev_desc->
131 		    block_read(ext4fs_block_dev_desc->dev,
132 				part_info->start + sector, 1,
133 				(unsigned long *) sec_buf) != 1) {
134 			printf("* %s read error - last part\n", __func__);
135 			return 0;
136 		}
137 		memcpy(buf, sec_buf, byte_len);
138 	}
139 	return 1;
140 }
141