| Kyungmin Park | a598345 | 2008-11-19 16:26:54 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) International Business Machines Corp., 2006 |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License as published by |
| 6 | * the Free Software Foundation; either version 2 of the License, or |
| 7 | * (at your option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 12 | * the GNU General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU General Public License |
| 15 | * along with this program; if not, write to the Free Software |
| 16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 17 | * |
| 18 | * Author: Artem Bityutskiy (Битюцкий Артём) |
| 19 | */ |
| 20 | |
| 21 | /* Here we keep miscellaneous functions which are used all over the UBI code */ |
| 22 | |
| 23 | #include <ubi_uboot.h> |
| 24 | #include "ubi.h" |
| 25 | |
| 26 | /** |
| 27 | * calc_data_len - calculate how much real data is stored in a buffer. |
| 28 | * @ubi: UBI device description object |
| 29 | * @buf: a buffer with the contents of the physical eraseblock |
| 30 | * @length: the buffer length |
| 31 | * |
| 32 | * This function calculates how much "real data" is stored in @buf and returnes |
| 33 | * the length. Continuous 0xFF bytes at the end of the buffer are not |
| 34 | * considered as "real data". |
| 35 | */ |
| 36 | int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf, |
| 37 | int length) |
| 38 | { |
| 39 | int i; |
| 40 | |
| 41 | ubi_assert(!(length & (ubi->min_io_size - 1))); |
| 42 | |
| 43 | for (i = length - 1; i >= 0; i--) |
| 44 | if (((const uint8_t *)buf)[i] != 0xFF) |
| 45 | break; |
| 46 | |
| 47 | /* The resulting length must be aligned to the minimum flash I/O size */ |
| 48 | length = ALIGN(i + 1, ubi->min_io_size); |
| 49 | return length; |
| 50 | } |
| 51 | |
| 52 | /** |
| 53 | * ubi_check_volume - check the contents of a static volume. |
| 54 | * @ubi: UBI device description object |
| 55 | * @vol_id: ID of the volume to check |
| 56 | * |
| 57 | * This function checks if static volume @vol_id is corrupted by fully reading |
| 58 | * it and checking data CRC. This function returns %0 if the volume is not |
| 59 | * corrupted, %1 if it is corrupted and a negative error code in case of |
| 60 | * failure. Dynamic volumes are not checked and zero is returned immediately. |
| 61 | */ |
| 62 | int ubi_check_volume(struct ubi_device *ubi, int vol_id) |
| 63 | { |
| 64 | void *buf; |
| 65 | int err = 0, i; |
| 66 | struct ubi_volume *vol = ubi->volumes[vol_id]; |
| 67 | |
| 68 | if (vol->vol_type != UBI_STATIC_VOLUME) |
| 69 | return 0; |
| 70 | |
| 71 | buf = vmalloc(vol->usable_leb_size); |
| 72 | if (!buf) |
| 73 | return -ENOMEM; |
| 74 | |
| 75 | for (i = 0; i < vol->used_ebs; i++) { |
| 76 | int size; |
| 77 | |
| 78 | if (i == vol->used_ebs - 1) |
| 79 | size = vol->last_eb_bytes; |
| 80 | else |
| 81 | size = vol->usable_leb_size; |
| 82 | |
| 83 | err = ubi_eba_read_leb(ubi, vol, i, buf, 0, size, 1); |
| 84 | if (err) { |
| 85 | if (err == -EBADMSG) |
| 86 | err = 1; |
| 87 | break; |
| 88 | } |
| 89 | } |
| 90 | |
| 91 | vfree(buf); |
| 92 | return err; |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * ubi_calculate_rsvd_pool - calculate how many PEBs must be reserved for bad |
| 97 | * eraseblock handling. |
| 98 | * @ubi: UBI device description object |
| 99 | */ |
| 100 | void ubi_calculate_reserved(struct ubi_device *ubi) |
| 101 | { |
| 102 | ubi->beb_rsvd_level = ubi->good_peb_count/100; |
| 103 | ubi->beb_rsvd_level *= CONFIG_MTD_UBI_BEB_RESERVE; |
| 104 | if (ubi->beb_rsvd_level < MIN_RESEVED_PEBS) |
| 105 | ubi->beb_rsvd_level = MIN_RESEVED_PEBS; |
| 106 | } |