// SPDX-License-Identifier: GPL-2.0-or-later/* * Copyright (c) International Business Machines Corp., 2006 * * Author: Artem Bityutskiy (Битюцкий Артём) */ /* Here we keep miscellaneous functions which are used all over the UBI code */ #include "ubi.h" /** * ubi_calc_data_len - calculate how much real data is stored in a buffer. * @ubi: UBI device description object * @buf: a buffer with the contents of the physical eraseblock * @length: the buffer length * * This function calculates how much "real data" is stored in @buf and returnes * the length. Continuous 0xFF bytes at the end of the buffer are not * considered as "real data". */int ubi_calc_data_len(const struct ubi_device *ubi, const void *buf,		      int length){	int i; 	ubi_assert(!(length & (ubi->min_io_size - 1))); 	for (i = length - 1; i >= 0; i--)		if (((const uint8_t *)buf)[i] != 0xFF)			break; 	/* The resulting length must be aligned to the minimum flash I/O size */	length = ALIGN(i + 1, ubi->min_io_size);	return length;} /** * ubi_check_volume - check the contents of a static volume. * @ubi: UBI device description object * @vol_id: ID of the volume to check * * This function checks if static volume @vol_id is corrupted by fully reading * it and checking data CRC. This function returns %0 if the volume is not * corrupted, %1 if it is corrupted and a negative error code in case of * failure. Dynamic volumes are not checked and zero is returned immediately. */int ubi_check_volume(struct ubi_device *ubi, int vol_id){	void *buf;	int err = 0, i;	struct ubi_volume *vol = ubi->volumes[vol_id]; 	if (vol->vol_type != UBI_STATIC_VOLUME)		return 0; 	buf = vmalloc(vol->usable_leb_size);	if (!buf)		return -ENOMEM; 	for (i = 0; i < vol->used_ebs; i++) {		int size; 		cond_resched(); 		if (i == vol->used_ebs - 1)			size = vol->last_eb_bytes;		else			size = vol->usable_leb_size; 		err = ubi_eba_read_leb(ubi, vol, i, buf, 0, size, 1);		if (err) {			if (mtd_is_eccerr(err))				err = 1;			break;		}	} 	vfree(buf);	return err;} /** * ubi_update_reserved - update bad eraseblock handling accounting data. * @ubi: UBI device description object * * This function calculates the gap between current number of PEBs reserved for * bad eraseblock handling and the required level of PEBs that must be * reserved, and if necessary, reserves more PEBs to fill that gap, according * to availability. Should be called with ubi->volumes_lock held. */void ubi_update_reserved(struct ubi_device *ubi){	int need = ubi->beb_rsvd_level - ubi->beb_rsvd_pebs; 	if (need <= 0 || ubi->avail_pebs == 0)		return; 	need = min_t(int, need, ubi->avail_pebs);	ubi->avail_pebs -= need;	ubi->rsvd_pebs += need;	ubi->beb_rsvd_pebs += need;	ubi_msg(ubi, "reserved more %d PEBs for bad PEB handling", need);} /** * ubi_calculate_reserved - calculate how many PEBs must be reserved for bad * eraseblock handling. * @ubi: UBI device description object */void ubi_calculate_reserved(struct ubi_device *ubi){	/*	 * Calculate the actual number of PEBs currently needed to be reserved	 * for future bad eraseblock handling.	 */	ubi->beb_rsvd_level = ubi->bad_peb_limit - ubi->bad_peb_count;	if (ubi->beb_rsvd_level < 0) {		ubi->beb_rsvd_level = 0;		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)",			 ubi->bad_peb_count, ubi->bad_peb_limit);	}} /** * ubi_check_pattern - check if buffer contains only a certain byte pattern. * @buf: buffer to check * @patt: the pattern to check * @size: buffer size in bytes * * This function returns %1 in there are only @patt bytes in @buf, and %0 if * something else was also found. */int ubi_check_pattern(const void *buf, uint8_t patt, int size){	int i; 	for (i = 0; i < size; i++)		if (((const uint8_t *)buf)[i] != patt)			return 0;	return 1;} /* Normal UBI messages */void ubi_msg(const struct ubi_device *ubi, const char *fmt, ...){	struct va_format vaf;	va_list args; 	va_start(args, fmt); 	vaf.fmt = fmt;	vaf.va = &args; 	pr_notice(UBI_NAME_STR "%d: %pV\n", ubi->ubi_num, &vaf); 	va_end(args);} /* UBI warning messages */void ubi_warn(const struct ubi_device *ubi, const char *fmt, ...){	struct va_format vaf;	va_list args; 	va_start(args, fmt); 	vaf.fmt = fmt;	vaf.va = &args; 	pr_warn(UBI_NAME_STR "%d warning: %ps: %pV\n",		ubi->ubi_num, __builtin_return_address(0), &vaf); 	va_end(args);} /* UBI error messages */void ubi_err(const struct ubi_device *ubi, const char *fmt, ...){	struct va_format vaf;	va_list args; 	va_start(args, fmt); 	vaf.fmt = fmt;	vaf.va = &args; 	pr_err(UBI_NAME_STR "%d error: %ps: %pV\n",	       ubi->ubi_num, __builtin_return_address(0), &vaf);	va_end(args);}