kernel/drivers/mtd/ubi/io.c, branch linux-rolling-stable

mtd: ubi: skip programming unused bits in ubi headers

2025-11-28T20:46:15Z

This patch prevents unnecessary programming of bits in ec_hdr and vid_hdr that are not used or read during normal UBI operation. These unused bits are typcially already set to 1 in erased flash and do not need to be explicitly programmed to 0 if they are not used. Programming such unused areas offers no functional benefit and may result in unnecessary flash wear, reducing the overall lifetime of the device. By skipping these writes, we preserve the flash state as much as possible and minimize wear caused by redundant operations. This change ensures that only necessary fields are written when preparing UBI headers, improving flash efficiency without affecting functionality. Additionally, the Kioxia TC58NVG1S3HTA00 datasheet (page 63) also notes that continuous program/erase cycling with a high percentage of '0' bits in the data pattern can accelerate block endurance degradation. This further supports avoiding large 0x00 patterns. Link: https://europe.kioxia.com/content/dam/kioxia/newidr/productinfo/datasheet/201910/DST_TC58NVG1S3HTA00-TDE_EN_31442.pdf Signed-off-by: Cheng Ming Lin Reviewed-by: Miquel Raynal Reviewed-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: Add six fault injection type for testing

2024-01-06T22:41:40Z

This commit adds six fault injection type for testing to cover the abnormal path of the UBI driver. Inject the following faults when the UBI reads the LEB: +----------------------------+-----------------------------------+ | Interface name | emulate behavior | +----------------------------+-----------------------------------+ | emulate_eccerr | ECC error | +----------------------------+-----------------------------------+ | emulate_read_failure | read failure | |----------------------------+-----------------------------------+ | emulate_io_ff | read content as all FF | |----------------------------+-----------------------------------+ | emulate_io_ff_bitflips | content FF with MTD err reported | +----------------------------+-----------------------------------+ | emulate_bad_hdr | bad leb header | |----------------------------+-----------------------------------+ | emulate_bad_hdr_ebadmsg | bad header with ECC err | +----------------------------+-----------------------------------+ Signed-off-by: ZhaoLong Wang Reviewed-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: Use the fault injection framework to enhance the fault injection capability

2024-01-06T22:38:55Z

To make debug parameters configurable at run time, use the fault injection framework to reconstruct the debugfs interface, and retain the legacy fault injection interface. Now, the file emulate_failures and fault_attr files control whether to enable fault emmulation. The file emulate_failures receives a mask that controls type and process of fault injection. Generally, for ease of use, you can directly enter a mask with all 1s. echo 0xffff > /sys/kernel/debug/ubi/ubi0/emulate_failures And you need to configure other fault-injection capabilities for testing purpose: echo 100 > /sys/kernel/debug/ubi/fault_inject/emulate_power_cut/probability echo 15 > /sys/kernel/debug/ubi/fault_inject/emulate_power_cut/space echo 2 > /sys/kernel/debug/ubi/fault_inject/emulate_power_cut/verbose echo -1 > /sys/kernel/debug/ubi/fault_inject/emulate_power_cut/times The CONFIG_MTD_UBI_FAULT_INJECTION to enable the Fault Injection is added to kconfig. Signed-off-by: ZhaoLong Wang Reviewed-by: Zhihao Cheng Signed-off-by: Richard Weinberger

ubi: Fix repeated words in comments

2022-09-21T09:32:27Z

Delete the redundant word 'a'. Delete the redundant word 'the'. Signed-off-by: Jilin Yuan Signed-off-by: Richard Weinberger

ubi: remove dead code in validate_vid_hdr()

2021-02-12T20:53:22Z

data_size is already checked against zero when vol_type matches UBI_VID_STATIC. Remove the following dead code. Signed-off-by: Jubin Zhong Signed-off-by: Richard Weinberger

ubi: Do not zero out EC and VID on ECC-ed NOR flashes

2020-12-13T20:57:21Z

For NOR flashes EC and VID are zeroed out before an erase is issued to make sure UBI does not mistakenly treat the PEB as used and associate it with an LEB. But on some flashes, like the Cypress Semper S28 SPI NOR flash family, multi-pass page programming is not allowed on the default ECC scheme. This means zeroing out these magic numbers will result in the flash throwing a page programming error. Do not zero out EC and VID for such flashes. A writesize > 1 is an indication of an ECC-ed flash. Signed-off-by: Pratyush Yadav Reviewed-by: Tudor Ambarus Signed-off-by: Richard Weinberger

mm: remove the pgprot argument to __vmalloc

2020-06-02T17:59:11Z

The pgprot argument to __vmalloc is always PAGE_KERNEL now, so remove it. Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Reviewed-by: Michael Kelley [hyperv] Acked-by: Gao Xiang [erofs] Acked-by: Peter Zijlstra (Intel) Acked-by: Wei Liu Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Daniel Vetter Cc: David Airlie Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Johannes Weiner Cc: "K. Y. Srinivasan" Cc: Laura Abbott Cc: Mark Rutland Cc: Minchan Kim Cc: Nitin Gupta Cc: Robin Murphy Cc: Sakari Ailus Cc: Stephen Hemminger Cc: Sumit Semwal Cc: Benjamin Herrenschmidt Cc: Catalin Marinas Cc: Heiko Carstens Cc: Paul Mackerras Cc: Vasily Gorbik Cc: Will Deacon Link: http://lkml.kernel.org/r/20200414131348.444715-22-hch@lst.de Signed-off-by: Linus Torvalds

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman

mtd: Unconditionally update ->fail_addr and ->addr in part_erase()

2018-03-15T17:22:26Z

->fail_addr and ->addr can be updated no matter the result of parent->_erase(), we just need to remove the code doing the same thing in mtd_erase_callback() to avoid adjusting those fields twice. Note that this can be done because all MTD users have been converted to not pass an erase_info->callback() and are thus only taking the ->addr_fail and ->addr fields into account after part_erase() has returned. While we're at it, get rid of the erase_info->mtd field which was only needed to let mtd_erase_callback() get the partition device back. Signed-off-by: Boris Brezillon Reviewed-by: Richard Weinberger

mtd: Stop assuming mtd_erase() is asynchronous

2018-03-15T17:21:07Z

None of the mtd->_erase() implementations work in an asynchronous manner, so let's simplify MTD users that call mtd_erase(). All they need to do is check the value returned by mtd_erase() and assume that != 0 means failure. Signed-off-by: Boris Brezillon Reviewed-by: Richard Weinberger