LXR uboot/fs/ext4/dev.c

   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 <memalign.h>
  29#include <ext4fs.h>
  30#include <ext_common.h>
  31#include "ext4_common.h"
  32
  33lbaint_t part_offset;
  34
  35static block_dev_desc_t *ext4fs_block_dev_desc;
  36static disk_partition_t *part_info;
  37
  38void ext4fs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info)
  39{
  40        assert(rbdd->blksz == (1 << rbdd->log2blksz));
  41        ext4fs_block_dev_desc = rbdd;
  42        get_fs()->dev_desc = rbdd;
  43        part_info = info;
  44        part_offset = info->start;
  45        get_fs()->total_sect = ((uint64_t)info->size * info->blksz) >>
  46                get_fs()->dev_desc->log2blksz;
  47}
  48
  49int ext4fs_devread(lbaint_t sector, int byte_offset, int byte_len, char *buf)
  50{
  51        unsigned block_len;
  52        int log2blksz = ext4fs_block_dev_desc->log2blksz;
  53        ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (ext4fs_block_dev_desc ?
  54                                                 ext4fs_block_dev_desc->blksz :
  55                                                 0));
  56        if (ext4fs_block_dev_desc == NULL) {
  57                printf("** Invalid Block Device Descriptor (NULL)\n");
  58                return 0;
  59        }
  60
  61        /* Check partition boundaries */
  62        if ((sector < 0) ||
  63            ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
  64             >= part_info->size)) {
  65                printf("%s read outside partition " LBAFU "\n", __func__,
  66                       sector);
  67                return 0;
  68        }
  69
  70        /* Get the read to the beginning of a partition */
  71        sector += byte_offset >> log2blksz;
  72        byte_offset &= ext4fs_block_dev_desc->blksz - 1;
  73
  74        debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);
  75
  76        if (byte_offset != 0) {
  77                int readlen;
  78                /* read first part which isn't aligned with start of sector */
  79                if (ext4fs_block_dev_desc->
  80                    block_read(ext4fs_block_dev_desc->dev,
  81                                part_info->start + sector, 1,
  82                                (unsigned long *) sec_buf) != 1) {
  83                        printf(" ** ext2fs_devread() read error **\n");
  84                        return 0;
  85                }
  86                readlen = min((int)ext4fs_block_dev_desc->blksz - byte_offset,
  87                              byte_len);
  88                memcpy(buf, sec_buf + byte_offset, readlen);
  89                buf += readlen;
  90                byte_len -= readlen;
  91                sector++;
  92        }
  93
  94        if (byte_len == 0)
  95                return 1;
  96
  97        /* read sector aligned part */
  98        block_len = byte_len & ~(ext4fs_block_dev_desc->blksz - 1);
  99
 100        if (block_len == 0) {
 101                ALLOC_CACHE_ALIGN_BUFFER(u8, p, ext4fs_block_dev_desc->blksz);
 102
 103                block_len = ext4fs_block_dev_desc->blksz;
 104                ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
 105                                                  part_info->start + sector,
 106                                                  1, (unsigned long *)p);
 107                memcpy(buf, p, byte_len);
 108                return 1;
 109        }
 110
 111        if (ext4fs_block_dev_desc->block_read(ext4fs_block_dev_desc->dev,
 112                                               part_info->start + sector,
 113                                               block_len >> log2blksz,
 114                                               (unsigned long *) buf) !=
 115                                               block_len >> log2blksz) {
 116                printf(" ** %s read error - block\n", __func__);
 117                return 0;
 118        }
 119        block_len = byte_len & ~(ext4fs_block_dev_desc->blksz - 1);
 120        buf += block_len;
 121        byte_len -= block_len;
 122        sector += block_len / ext4fs_block_dev_desc->blksz;
 123
 124        if (byte_len != 0) {
 125                /* read rest of data which are not in whole sector */
 126                if (ext4fs_block_dev_desc->
 127                    block_read(ext4fs_block_dev_desc->dev,
 128                                part_info->start + sector, 1,
 129                                (unsigned long *) sec_buf) != 1) {
 130                        printf("* %s read error - last part\n", __func__);
 131                        return 0;
 132                }
 133                memcpy(buf, sec_buf, byte_len);
 134        }
 135        return 1;
 136}
 137
 138int ext4_read_superblock(char *buffer)
 139{
 140        struct ext_filesystem *fs = get_fs();
 141        int sect = SUPERBLOCK_START >> fs->dev_desc->log2blksz;
 142        int off = SUPERBLOCK_START % fs->dev_desc->blksz;
 143
 144        return ext4fs_devread(sect, off, SUPERBLOCK_SIZE,
 145                                buffer);
 146}
 147