xref: /openbmc/u-boot/fs/ext4/dev.c (revision bfc37f3cb8adf48297bed1088d42df5d119ec12d)
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 <config.h>
28  #include <ext4fs.h>
29  #include <ext_common.h>
30  #include "ext4_common.h"
31  
32  lbaint_t part_offset;
33  
34  static block_dev_desc_t *ext4fs_block_dev_desc;
35  static disk_partition_t *part_info;
36  
37  void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info)
38  {
39  	assert(rbdd->blksz == (1 << rbdd->log2blksz));
40  	ext4fs_block_dev_desc = rbdd;
41  	get_fs()->dev_desc = rbdd;
42  	part_info = info;
43  	part_offset = info->start;
44  	get_fs()->total_sect = ((uint64_t)info->size * info->blksz) >>
45  		get_fs()->dev_desc->log2blksz;
46  }
47  
48  int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf)
49  {
50  	unsigned block_len;
51  	int log2blksz = ext4fs_block_dev_desc->log2blksz;
52  	ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (ext4fs_block_dev_desc ?
53  						 ext4fs_block_dev_desc->blksz :
54  						 0));
55  	if (ext4fs_block_dev_desc == NULL) {
56  		printf("** Invalid Block Device Descriptor (NULL)\n");
57  		return 0;
58  	}
59  
60  	/* Check partition boundaries */
61  	if ((sector < 0) ||
62  	    ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
63  	     >= part_info->size)) {
64  		printf("%s read outside partition " LBAFU "\n", __func__,
65  		       sector);
66  		return 0;
67  	}
68  
69  	/* Get the read to the beginning of a partition */
70  	sector += byte_offset >> log2blksz;
71  	byte_offset &= ext4fs_block_dev_desc->blksz - 1;
72  
73  	debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);
74  
75  	if (byte_offset != 0) {
76  		int readlen;
77  		/* read first part which isn't aligned with start of sector */
78  		if (ext4fs_block_dev_desc->
79  		    block_read(ext4fs_block_dev_desc->dev,
80  				part_info->start + sector, 1,
81  				(unsigned long *) sec_buf) != 1) {
82  			printf(" ** ext2fs_devread() read error **\n");
83  			return 0;
84  		}
85  		readlen = min((int)ext4fs_block_dev_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_block_dev_desc->blksz - 1);
98  
99  	if (block_len == 0) {
100  		ALLOC_CACHE_ALIGN_BUFFER(u8, p, ext4fs_block_dev_desc->blksz);
101  
102  		block_len = ext4fs_block_dev_desc->blksz;
103  		ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
104  						  part_info->start + sector,
105  						  1, (unsigned long *)p);
106  		memcpy(buf, p, byte_len);
107  		return 1;
108  	}
109  
110  	if (ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
111  					       part_info->start + sector,
112  					       block_len >> log2blksz,
113  					       (unsigned long *) buf) !=
114  					       block_len >> log2blksz) {
115  		printf(" ** %s read error - block\n", __func__);
116  		return 0;
117  	}
118  	block_len = byte_len & ~(ext4fs_block_dev_desc->blksz - 1);
119  	buf += block_len;
120  	byte_len -= block_len;
121  	sector += block_len / ext4fs_block_dev_desc->blksz;
122  
123  	if (byte_len != 0) {
124  		/* read rest of data which are not in whole sector */
125  		if (ext4fs_block_dev_desc->
126  		    block_read(ext4fs_block_dev_desc->dev,
127  				part_info->start + sector, 1,
128  				(unsigned long *) sec_buf) != 1) {
129  			printf("* %s read error - last part\n", __func__);
130  			return 0;
131  		}
132  		memcpy(buf, sec_buf, byte_len);
133  	}
134  	return 1;
135  }
136  
137  int ext4_read_superblock(char *buffer)
138  {
139  	struct ext_filesystem *fs = get_fs();
140  	int sect = SUPERBLOCK_START >> fs->dev_desc->log2blksz;
141  	int off = SUPERBLOCK_START % fs->dev_desc->blksz;
142  
143  	return ext4fs_devread(sect, off, SUPERBLOCK_SIZE,
144  				buffer);
145  }
146