xref: /openbmc/u-boot/fs/ext4/dev.c (revision 46c07bcf12a7d6478b5e2f3e4b4c961d84428c6c)
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 <ext_common.h>
42 
43 static block_dev_desc_t *ext4fs_block_dev_desc;
44 static disk_partition_t part_info;
45 
46 int ext4fs_set_blk_dev(block_dev_desc_t *rbdd, int part)
47 {
48 	ext4fs_block_dev_desc = rbdd;
49 
50 	if (part == 0) {
51 		/* disk doesn't use partition table */
52 		part_info.start = 0;
53 		part_info.size = rbdd->lba;
54 		part_info.blksz = rbdd->blksz;
55 	} else {
56 		if (get_partition_info(ext4fs_block_dev_desc,
57 					part, &part_info))
58 			return 0;
59 	}
60 	return part_info.size;
61 }
62 
63 int ext4fs_devread(int sector, int byte_offset, int byte_len, char *buf)
64 {
65 	ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, SECTOR_SIZE);
66 	unsigned block_len;
67 
68 	/* Check partition boundaries */
69 	if ((sector < 0)
70 	    || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS)) >=
71 		part_info.size)) {
72 		printf("%s read outside partition %d\n", __func__, sector);
73 		return 0;
74 	}
75 
76 	/* Get the read to the beginning of a partition */
77 	sector += byte_offset >> SECTOR_BITS;
78 	byte_offset &= SECTOR_SIZE - 1;
79 
80 	debug(" <%d, %d, %d>\n", sector, byte_offset, byte_len);
81 
82 	if (ext4fs_block_dev_desc == NULL) {
83 		printf("** Invalid Block Device Descriptor (NULL)\n");
84 		return 0;
85 	}
86 
87 	if (byte_offset != 0) {
88 		/* read first part which isn't aligned with start of sector */
89 		if (ext4fs_block_dev_desc->
90 		    block_read(ext4fs_block_dev_desc->dev,
91 				part_info.start + sector, 1,
92 				(unsigned long *) sec_buf) != 1) {
93 			printf(" ** ext2fs_devread() read error **\n");
94 			return 0;
95 		}
96 		memcpy(buf, sec_buf + byte_offset,
97 			min(SECTOR_SIZE - byte_offset, byte_len));
98 		buf += min(SECTOR_SIZE - byte_offset, byte_len);
99 		byte_len -= min(SECTOR_SIZE - byte_offset, byte_len);
100 		sector++;
101 	}
102 
103 	if (byte_len == 0)
104 		return 1;
105 
106 	/* read sector aligned part */
107 	block_len = byte_len & ~(SECTOR_SIZE - 1);
108 
109 	if (block_len == 0) {
110 		ALLOC_CACHE_ALIGN_BUFFER(u8, p, SECTOR_SIZE);
111 
112 		block_len = SECTOR_SIZE;
113 		ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
114 						  part_info.start + sector,
115 						  1, (unsigned long *)p);
116 		memcpy(buf, p, byte_len);
117 		return 1;
118 	}
119 
120 	if (ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
121 					       part_info.start + sector,
122 					       block_len / SECTOR_SIZE,
123 					       (unsigned long *) buf) !=
124 					       block_len / SECTOR_SIZE) {
125 		printf(" ** %s read error - block\n", __func__);
126 		return 0;
127 	}
128 	block_len = byte_len & ~(SECTOR_SIZE - 1);
129 	buf += block_len;
130 	byte_len -= block_len;
131 	sector += block_len / SECTOR_SIZE;
132 
133 	if (byte_len != 0) {
134 		/* read rest of data which are not in whole sector */
135 		if (ext4fs_block_dev_desc->
136 		    block_read(ext4fs_block_dev_desc->dev,
137 				part_info.start + sector, 1,
138 				(unsigned long *) sec_buf) != 1) {
139 			printf("* %s read error - last part\n", __func__);
140 			return 0;
141 		}
142 		memcpy(buf, sec_buf, byte_len);
143 	}
144 	return 1;
145 }
146