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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) International Business Machines Corp., 20064 *5 * Author: Artem Bityutskiy (Битюцкий Артём)6 */7 8/* Here we keep miscellaneous functions which are used all over the UBI code */9 10#include "ubi.h"11 12/**13 * ubi_calc_data_len - calculate how much real data is stored in a buffer.14 * @ubi: UBI device description object15 * @buf: a buffer with the contents of the physical eraseblock16 * @length: the buffer length17 *18 * This function calculates how much "real data" is stored in @buf and returnes19 * the length. Continuous 0xFF bytes at the end of the buffer are not20 * considered as "real data".21 */22int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,23 int length)24{25 int i;26 27 ubi_assert(!(length & (ubi->min_io_size - 1)));28 29 for (i = length - 1; i >= 0; i--)30 if (((const uint8_t *)buf)[i] != 0xFF)31 break;32 33 /* The resulting length must be aligned to the minimum flash I/O size */34 length = ALIGN(i + 1, ubi->min_io_size);35 return length;36}37 38/**39 * ubi_check_volume - check the contents of a static volume.40 * @ubi: UBI device description object41 * @vol_id: ID of the volume to check42 *43 * This function checks if static volume @vol_id is corrupted by fully reading44 * it and checking data CRC. This function returns %0 if the volume is not45 * corrupted, %1 if it is corrupted and a negative error code in case of46 * failure. Dynamic volumes are not checked and zero is returned immediately.47 */48int ubi_check_volume(struct ubi_device *ubi, int vol_id)49{50 void *buf;51 int err = 0, i;52 struct ubi_volume *vol = ubi->volumes[vol_id];53 54 if (vol->vol_type != UBI_STATIC_VOLUME)55 return 0;56 57 buf = vmalloc(vol->usable_leb_size);58 if (!buf)59 return -ENOMEM;60 61 for (i = 0; i < vol->used_ebs; i++) {62 int size;63 64 cond_resched();65 66 if (i == vol->used_ebs - 1)67 size = vol->last_eb_bytes;68 else69 size = vol->usable_leb_size;70 71 err = ubi_eba_read_leb(ubi, vol, i, buf, 0, size, 1);72 if (err) {73 if (mtd_is_eccerr(err))74 err = 1;75 break;76 }77 }78 79 vfree(buf);80 return err;81}82 83/**84 * ubi_update_reserved - update bad eraseblock handling accounting data.85 * @ubi: UBI device description object86 *87 * This function calculates the gap between current number of PEBs reserved for88 * bad eraseblock handling and the required level of PEBs that must be89 * reserved, and if necessary, reserves more PEBs to fill that gap, according90 * to availability. Should be called with ubi->volumes_lock held.91 */92void ubi_update_reserved(struct ubi_device *ubi)93{94 int need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs;95 96 if (need <= 0 || ubi->avail_pebs == 0)97 return;98 99 need = min_t(int, need, ubi->avail_pebs);100 ubi->avail_pebs -= need;101 ubi->rsvd_pebs += need;102 ubi->beb_rsvd_pebs += need;103 ubi_msg(ubi, "reserved more %d PEBs for bad PEB handling", need);104}105 106/**107 * ubi_calculate_reserved - calculate how many PEBs must be reserved for bad108 * eraseblock handling.109 * @ubi: UBI device description object110 */111void ubi_calculate_reserved(struct ubi_device *ubi)112{113 /*114 * Calculate the actual number of PEBs currently needed to be reserved115 * for future bad eraseblock handling.116 */117 ubi->beb_rsvd_level = ubi->bad_peb_limit - ubi->bad_peb_count;118 if (ubi->beb_rsvd_level < 0) {119 ubi->beb_rsvd_level = 0;120 ubi_warn(ubi, "number of bad PEBs (%d) is above the expected limit (%d), not reserving any PEBs for bad PEB handling, will use available PEBs (if any)",121 ubi->bad_peb_count, ubi->bad_peb_limit);122 }123}124 125/**126 * ubi_check_pattern - check if buffer contains only a certain byte pattern.127 * @buf: buffer to check128 * @patt: the pattern to check129 * @size: buffer size in bytes130 *131 * This function returns %1 in there are only @patt bytes in @buf, and %0 if132 * something else was also found.133 */134int ubi_check_pattern(const void *buf, uint8_t patt, int size)135{136 int i;137 138 for (i = 0; i < size; i++)139 if (((const uint8_t *)buf)[i] != patt)140 return 0;141 return 1;142}143 144/* Normal UBI messages */145void ubi_msg(const struct ubi_device *ubi, const char *fmt, ...)146{147 struct va_format vaf;148 va_list args;149 150 va_start(args, fmt);151 152 vaf.fmt = fmt;153 vaf.va = &args;154 155 pr_notice(UBI_NAME_STR "%d: %pV\n", ubi->ubi_num, &vaf);156 157 va_end(args);158}159 160/* UBI warning messages */161void ubi_warn(const struct ubi_device *ubi, const char *fmt, ...)162{163 struct va_format vaf;164 va_list args;165 166 va_start(args, fmt);167 168 vaf.fmt = fmt;169 vaf.va = &args;170 171 pr_warn(UBI_NAME_STR "%d warning: %ps: %pV\n",172 ubi->ubi_num, __builtin_return_address(0), &vaf);173 174 va_end(args);175}176 177/* UBI error messages */178void ubi_err(const struct ubi_device *ubi, const char *fmt, ...)179{180 struct va_format vaf;181 va_list args;182 183 va_start(args, fmt);184 185 vaf.fmt = fmt;186 vaf.va = &args;187 188 pr_err(UBI_NAME_STR "%d error: %ps: %pV\n",189 ubi->ubi_num, __builtin_return_address(0), &vaf);190 va_end(args);191}192