xref: /openbmc/u-boot/fs/ext4/dev.c (revision 1d2c0506)
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  * SPDX-License-Identifier:	GPL-2.0+
18  */
19 
20 /*
21  * Changelog:
22  *	0.1 - Newly created file for ext4fs support. Taken from
23  *		fs/ext2/dev.c file in uboot.
24  */
25 
26 #include <common.h>
27 #include <blk.h>
28 #include <config.h>
29 #include <memalign.h>
30 #include <ext4fs.h>
31 #include <ext_common.h>
32 #include "ext4_common.h"
33 
34 lbaint_t part_offset;
35 
36 static struct blk_desc *ext4fs_blk_desc;
37 static disk_partition_t *part_info;
38 
39 void ext4fs_set_blk_dev(struct blk_desc *rbdd, disk_partition_t *info)
40 {
41 	assert(rbdd->blksz == (1 << rbdd->log2blksz));
42 	ext4fs_blk_desc = rbdd;
43 	get_fs()->dev_desc = rbdd;
44 	part_info = info;
45 	part_offset = info->start;
46 	get_fs()->total_sect = ((uint64_t)info->size * info->blksz) >>
47 		get_fs()->dev_desc->log2blksz;
48 }
49 
50 int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf)
51 {
52 	unsigned block_len;
53 	int log2blksz = ext4fs_blk_desc->log2blksz;
54 	ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (ext4fs_blk_desc ?
55 						 ext4fs_blk_desc->blksz :
56 						 0));
57 	if (ext4fs_blk_desc == NULL) {
58 		printf("** Invalid Block Device Descriptor (NULL)\n");
59 		return 0;
60 	}
61 
62 	/* Check partition boundaries */
63 	if ((sector < 0) ||
64 	    ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
65 	     >= part_info->size)) {
66 		printf("%s read outside partition " LBAFU "\n", __func__,
67 		       sector);
68 		return 0;
69 	}
70 
71 	/* Get the read to the beginning of a partition */
72 	sector += byte_offset >> log2blksz;
73 	byte_offset &= ext4fs_blk_desc->blksz - 1;
74 
75 	debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);
76 
77 	if (byte_offset != 0) {
78 		int readlen;
79 		/* read first part which isn't aligned with start of sector */
80 		if (blk_dread(ext4fs_blk_desc, part_info->start + sector, 1,
81 			      (void *)sec_buf) != 1) {
82 			printf(" ** ext2fs_devread() read error **\n");
83 			return 0;
84 		}
85 		readlen = min((int)ext4fs_blk_desc->blksz - byte_offset,
86 			      byte_len);
87 		memcpy(buf, sec_buf + byte_offset, readlen);
88 		buf += readlen;
89 		byte_len -= readlen;
90 		sector++;
91 	}
92 
93 	if (byte_len == 0)
94 		return 1;
95 
96 	/* read sector aligned part */
97 	block_len = byte_len & ~(ext4fs_blk_desc->blksz - 1);
98 
99 	if (block_len == 0) {
100 		ALLOC_CACHE_ALIGN_BUFFER(u8, p, ext4fs_blk_desc->blksz);
101 
102 		block_len = ext4fs_blk_desc->blksz;
103 		blk_dread(ext4fs_blk_desc, part_info->start + sector, 1,
104 			  (void *)p);
105 		memcpy(buf, p, byte_len);
106 		return 1;
107 	}
108 
109 	if (blk_dread(ext4fs_blk_desc, part_info->start + sector,
110 		      block_len >> log2blksz, (void *)buf) !=
111 			block_len >> log2blksz) {
112 		printf(" ** %s read error - block\n", __func__);
113 		return 0;
114 	}
115 	block_len = byte_len & ~(ext4fs_blk_desc->blksz - 1);
116 	buf += block_len;
117 	byte_len -= block_len;
118 	sector += block_len / ext4fs_blk_desc->blksz;
119 
120 	if (byte_len != 0) {
121 		/* read rest of data which are not in whole sector */
122 		if (blk_dread(ext4fs_blk_desc, part_info->start + sector, 1,
123 			      (void *)sec_buf) != 1) {
124 			printf("* %s read error - last part\n", __func__);
125 			return 0;
126 		}
127 		memcpy(buf, sec_buf, byte_len);
128 	}
129 	return 1;
130 }
131 
132 int ext4_read_superblock(char *buffer)
133 {
134 	struct ext_filesystem *fs = get_fs();
135 	int sect = SUPERBLOCK_START >> fs->dev_desc->log2blksz;
136 	int off = SUPERBLOCK_START % fs->dev_desc->blksz;
137 
138 	return ext4fs_devread(sect, off, SUPERBLOCK_SIZE,
139 				buffer);
140 }
141