summaryrefslogtreecommitdiffstats
path: root/fs/ext4/dev.c
blob: 3eef66f84781a303b9277a88082da8a089f323e8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
/*
 * (C) Copyright 2011 - 2012 Samsung Electronics
 * EXT4 filesystem implementation in Uboot by
 * Uma Shankar <uma.shankar@samsung.com>
 * Manjunatha C Achar <a.manjunatha@samsung.com>
 *
 * made from existing ext2/dev.c file of Uboot
 * (C) Copyright 2004
 * esd gmbh <www.esd-electronics.com>
 * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
 *
 * based on code of fs/reiserfs/dev.c by
 *
 * (C) Copyright 2003 - 2004
 * Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * Changelog:
 *	0.1 - Newly created file for ext4fs support. Taken from
 *		fs/ext2/dev.c file in uboot.
 */

#include <common.h>
#include <config.h>
#include <memalign.h>
#include <ext4fs.h>
#include <ext_common.h>
#include "ext4_common.h"

lbaint_t part_offset;

static struct blk_desc *ext4fs_blk_desc;
static disk_partition_t *part_info;

void ext4fs_set_blk_dev(struct blk_desc *rbdd, disk_partition_t *info)
{
	assert(rbdd->blksz == (1 << rbdd->log2blksz));
	ext4fs_blk_desc = rbdd;
	get_fs()->dev_desc = rbdd;
	part_info = info;
	part_offset = info->start;
	get_fs()->total_sect = ((uint64_t)info->size * info->blksz) >>
		get_fs()->dev_desc->log2blksz;
}

int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf)
{
	unsigned block_len;
	int log2blksz = ext4fs_blk_desc->log2blksz;
	ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (ext4fs_blk_desc ?
						 ext4fs_blk_desc->blksz :
						 0));
	if (ext4fs_blk_desc == NULL) {
		printf("** Invalid Block Device Descriptor (NULL)\n");
		return 0;
	}

	/* Check partition boundaries */
	if ((sector < 0) ||
	    ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
	     >= part_info->size)) {
		printf("%s read outside partition " LBAFU "\n", __func__,
		       sector);
		return 0;
	}

	/* Get the read to the beginning of a partition */
	sector += byte_offset >> log2blksz;
	byte_offset &= ext4fs_blk_desc->blksz - 1;

	debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);

	if (byte_offset != 0) {
		int readlen;
		/* read first part which isn't aligned with start of sector */
		if (ext4fs_blk_desc->block_read(ext4fs_blk_desc,
						part_info->start + sector,
						1, (void *)sec_buf) != 1) {
			printf(" ** ext2fs_devread() read error **\n");
			return 0;
		}
		readlen = min((int)ext4fs_blk_desc->blksz - byte_offset,
			      byte_len);
		memcpy(buf, sec_buf + byte_offset, readlen);
		buf += readlen;
		byte_len -= readlen;
		sector++;
	}

	if (byte_len == 0)
		return 1;

	/* read sector aligned part */
	block_len = byte_len & ~(ext4fs_blk_desc->blksz - 1);

	if (block_len == 0) {
		ALLOC_CACHE_ALIGN_BUFFER(u8, p, ext4fs_blk_desc->blksz);

		block_len = ext4fs_blk_desc->blksz;
		ext4fs_blk_desc->block_read(ext4fs_blk_desc,
						  part_info->start + sector,
						  1, (void *)p);
		memcpy(buf, p, byte_len);
		return 1;
	}

	if (ext4fs_blk_desc->block_read(ext4fs_blk_desc,
					part_info->start + sector,
					block_len >> log2blksz, (void *)buf)
				!= block_len >> log2blksz) {
		printf(" ** %s read error - block\n", __func__);
		return 0;
	}
	block_len = byte_len & ~(ext4fs_blk_desc->blksz - 1);
	buf += block_len;
	byte_len -= block_len;
	sector += block_len / ext4fs_blk_desc->blksz;

	if (byte_len != 0) {
		/* read rest of data which are not in whole sector */
		if (ext4fs_blk_desc->block_read(ext4fs_blk_desc,
						part_info->start + sector,
						1, (void *)sec_buf) != 1) {
			printf("* %s read error - last part\n", __func__);
			return 0;
		}
		memcpy(buf, sec_buf, byte_len);
	}
	return 1;
}

int ext4_read_superblock(char *buffer)
{
	struct ext_filesystem *fs = get_fs();
	int sect = SUPERBLOCK_START >> fs->dev_desc->log2blksz;
	int off = SUPERBLOCK_START % fs->dev_desc->blksz;

	return ext4fs_devread(sect, off, SUPERBLOCK_SIZE,
				buffer);
}
OpenPOWER on IntegriCloud