LXR uboot/fs/fs_internal.c

   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * 2017 by Marek Behun <marek.behun@nic.cz>
   4 *
   5 * Derived from code in ext4/dev.c, which was based on reiserfs/dev.c
   6 */
   7
   8#define LOG_CATEGORY LOGC_CORE
   9
  10#include <common.h>
  11#include <blk.h>
  12#include <compiler.h>
  13#include <log.h>
  14#include <part.h>
  15#include <memalign.h>
  16
  17int fs_devread(struct blk_desc *blk, struct disk_partition *partition,
  18               lbaint_t sector, int byte_offset, int byte_len, char *buf)
  19{
  20        unsigned block_len;
  21        int log2blksz;
  22        ALLOC_CACHE_ALIGN_BUFFER(char, sec_buf, (blk ? blk->blksz : 0));
  23        if (blk == NULL) {
  24                log_err("** Invalid Block Device Descriptor (NULL)\n");
  25                return 0;
  26        }
  27        log2blksz = blk->log2blksz;
  28
  29        /* Check partition boundaries */
  30        if ((sector + ((byte_offset + byte_len - 1) >> log2blksz))
  31            >= partition->size) {
  32                log_err("%s read outside partition " LBAFU "\n", __func__,
  33                        sector);
  34                return 0;
  35        }
  36
  37        /* Get the read to the beginning of a partition */
  38        sector += byte_offset >> log2blksz;
  39        byte_offset &= blk->blksz - 1;
  40
  41        log_debug(" <" LBAFU ", %d, %d>\n", sector, byte_offset, byte_len);
  42
  43        if (byte_offset != 0) {
  44                int readlen;
  45                /* read first part which isn't aligned with start of sector */
  46                if (blk_dread(blk, partition->start + sector, 1,
  47                              (void *)sec_buf) != 1) {
  48                        log_err(" ** %s read error **\n", __func__);
  49                        return 0;
  50                }
  51                readlen = min((int)blk->blksz - byte_offset,
  52                              byte_len);
  53                memcpy(buf, sec_buf + byte_offset, readlen);
  54                buf += readlen;
  55                byte_len -= readlen;
  56                sector++;
  57        }
  58
  59        if (byte_len == 0)
  60                return 1;
  61
  62        /* read sector aligned part */
  63        block_len = byte_len & ~(blk->blksz - 1);
  64
  65        if (block_len == 0) {
  66                ALLOC_CACHE_ALIGN_BUFFER(u8, p, blk->blksz);
  67
  68                block_len = blk->blksz;
  69                blk_dread(blk, partition->start + sector, 1,
  70                          (void *)p);
  71                memcpy(buf, p, byte_len);
  72                return 1;
  73        }
  74
  75        if (blk_dread(blk, partition->start + sector,
  76                      block_len >> log2blksz, (void *)buf) !=
  77                        block_len >> log2blksz) {
  78                log_err(" ** %s read error - block\n", __func__);
  79                return 0;
  80        }
  81        block_len = byte_len & ~(blk->blksz - 1);
  82        buf += block_len;
  83        byte_len -= block_len;
  84        sector += block_len / blk->blksz;
  85
  86        if (byte_len != 0) {
  87                /* read rest of data which are not in whole sector */
  88                if (blk_dread(blk, partition->start + sector, 1,
  89                              (void *)sec_buf) != 1) {
  90                        log_err("* %s read error - last part\n", __func__);
  91                        return 0;
  92                }
  93                memcpy(buf, sec_buf, byte_len);
  94        }
  95        return 1;
  96}
  97