diff options
Diffstat (limited to 'drivers/mtd/ubi/misc.c')
-rw-r--r-- | drivers/mtd/ubi/misc.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/drivers/mtd/ubi/misc.c b/drivers/mtd/ubi/misc.c new file mode 100644 index 000000000000..38d4e6757dc7 --- /dev/null +++ b/drivers/mtd/ubi/misc.c | |||
@@ -0,0 +1,105 @@ | |||
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.h" | ||
24 | |||
25 | /** | ||
26 | * calc_data_len - calculate how much real data is stored in a buffer. | ||
27 | * @ubi: UBI device description object | ||
28 | * @buf: a buffer with the contents of the physical eraseblock | ||
29 | * @length: the buffer length | ||
30 | * | ||
31 | * This function calculates how much "real data" is stored in @buf and returnes | ||
32 | * the length. Continuous 0xFF bytes at the end of the buffer are not | ||
33 | * considered as "real data". | ||
34 | */ | ||
35 | int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf, | ||
36 | int length) | ||
37 | { | ||
38 | int i; | ||
39 | |||
40 | ubi_assert(length % ubi->min_io_size == 0); | ||
41 | |||
42 | for (i = length - 1; i >= 0; i--) | ||
43 | if (((const uint8_t *)buf)[i] != 0xFF) | ||
44 | break; | ||
45 | |||
46 | /* The resulting length must be aligned to the minimum flash I/O size */ | ||
47 | length = ALIGN(i + 1, ubi->min_io_size); | ||
48 | return length; | ||
49 | } | ||
50 | |||
51 | /** | ||
52 | * ubi_check_volume - check the contents of a static volume. | ||
53 | * @ubi: UBI device description object | ||
54 | * @vol_id: ID of the volume to check | ||
55 | * | ||
56 | * This function checks if static volume @vol_id is corrupted by fully reading | ||
57 | * it and checking data CRC. This function returns %0 if the volume is not | ||
58 | * corrupted, %1 if it is corrupted and a negative error code in case of | ||
59 | * failure. Dynamic volumes are not checked and zero is returned immediately. | ||
60 | */ | ||
61 | int ubi_check_volume(struct ubi_device *ubi, int vol_id) | ||
62 | { | ||
63 | void *buf; | ||
64 | int err = 0, i; | ||
65 | struct ubi_volume *vol = ubi->volumes[vol_id]; | ||
66 | |||
67 | if (vol->vol_type != UBI_STATIC_VOLUME) | ||
68 | return 0; | ||
69 | |||
70 | buf = kmalloc(vol->usable_leb_size, GFP_KERNEL); | ||
71 | if (!buf) | ||
72 | return -ENOMEM; | ||
73 | |||
74 | for (i = 0; i < vol->used_ebs; i++) { | ||
75 | int size; | ||
76 | |||
77 | if (i == vol->used_ebs - 1) | ||
78 | size = vol->last_eb_bytes; | ||
79 | else | ||
80 | size = vol->usable_leb_size; | ||
81 | |||
82 | err = ubi_eba_read_leb(ubi, vol_id, i, buf, 0, size, 1); | ||
83 | if (err) { | ||
84 | if (err == -EBADMSG) | ||
85 | err = 1; | ||
86 | break; | ||
87 | } | ||
88 | } | ||
89 | |||
90 | kfree(buf); | ||
91 | return err; | ||
92 | } | ||
93 | |||
94 | /** | ||
95 | * ubi_calculate_rsvd_pool - calculate how many PEBs must be reserved for bad | ||
96 | * eraseblock handling. | ||
97 | * @ubi: UBI device description object | ||
98 | */ | ||
99 | void ubi_calculate_reserved(struct ubi_device *ubi) | ||
100 | { | ||
101 | ubi->beb_rsvd_level = ubi->good_peb_count/100; | ||
102 | ubi->beb_rsvd_level *= CONFIG_MTD_UBI_BEB_RESERVE; | ||
103 | if (ubi->beb_rsvd_level < MIN_RESEVED_PEBS) | ||
104 | ubi->beb_rsvd_level = MIN_RESEVED_PEBS; | ||
105 | } | ||