linux/drivers/mtd
Xiaoming Ni 5788ccf3c8 mtd: clear cache_state to avoid writing to bad blocks repeatedly
The function call process is as follows:
	mtd_blktrans_work()
	  while (1)
	    do_blktrans_request()
	      mtdblock_writesect()
	        do_cached_write()
	          write_cached_data() /*if cache_state is STATE_DIRTY*/
	            erase_write()

write_cached_data() returns failure without modifying cache_state
and cache_offset. So when do_cached_write() is called again,
write_cached_data() will be called again to perform erase_write()
on the same cache_offset.

But if this cache_offset points to a bad block, erase_write() will
always return -EIO. Writing to this mtdblk is equivalent to losing
the current data, and repeatedly writing to the bad block.

Repeatedly writing a bad block has no real benefits,
but brings some negative effects:
1 Lost subsequent data
2 Loss of flash device life
3 erase_write() bad blocks are very time-consuming. For example:
	the function do_erase_oneblock() in chips/cfi_cmdset_0020.c or
	chips/cfi_cmdset_0002.c may take more than 20 seconds to return

Therefore, when erase_write() returns -EIO in write_cached_data(),
clear cache_state to avoid writing to bad blocks repeatedly.

Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
2020-06-05 10:16:14 +02:00
..
chips mtd: cfi_cmdset_0001: Support the absence of protection registers 2020-04-30 23:42:57 +05:30
devices lib/bch: Allow easy bit swapping 2020-05-24 20:48:11 +02:00
hyperbus mtd: hyperbus: move direct mapping setup to AM654 HBMC driver 2020-03-03 10:13:11 +05:30
lpddr mtd: Convert fallthrough comments into statements 2020-03-30 10:14:54 +02:00
maps mtd: physmap_of_gemini: remove defined but not used symbol 'syscon_match' 2020-06-05 10:15:44 +02:00
nand Raw NAND core changes: 2020-06-01 19:50:58 +02:00
parsers mtd: parser: cmdline: Support MTD names containing one or more colons 2020-06-05 10:16:14 +02:00
spi-nor mtd: spi-nor: winbond: Fix 4-byte opcode support for w25q256 2020-05-31 08:34:16 +03:00
tests treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 326 2019-06-05 17:37:06 +02:00
ubi Raw NAND core changes: 2020-06-01 19:50:58 +02:00
ftl.c
inftlcore.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
inftlmount.c mtd: fix spelling mistake "BlockMultiplerBits" -> "BlockMultiplierBits" 2020-03-11 14:49:30 +01:00
Kconfig mtd: parsers: Move CMDLINE parser 2019-09-15 23:50:50 +02:00
Makefile mtd: parsers: Move CMDLINE parser 2019-09-15 23:50:50 +02:00
mtd_blkdevs.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102 2019-05-24 17:39:00 +02:00
mtdblock_ro.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102 2019-05-24 17:39:00 +02:00
mtdblock.c mtd: clear cache_state to avoid writing to bad blocks repeatedly 2020-06-05 10:16:14 +02:00
mtdchar.c mtd: implement proper partition handling 2020-03-11 14:49:30 +01:00
mtdconcat.c mtd: concat: Fix a comment referring to an unknown symbol 2020-01-27 17:45:31 +01:00
mtdcore.c Raw NAND core changes: 2020-06-01 19:50:58 +02:00
mtdcore.h mtd: Provide fs_context-aware mount_mtd() replacement 2019-09-05 14:34:23 -04:00
mtdoops.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336 2019-06-05 17:37:07 +02:00
mtdpart.c mtd: Add support for emulated SLC mode on MLC NANDs 2020-05-11 09:51:41 +02:00
mtdsuper.c mtd: Kill mount_mtd() 2019-09-05 14:34:26 -04:00
mtdswap.c mtd: no need to check return value of debugfs_create functions 2019-11-14 10:57:38 +01:00
nftlcore.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
nftlmount.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
rfd_ftl.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
sm_ftl.c mtd: sm_ftl: fix NULL pointer warning 2020-01-09 20:09:55 +01:00
sm_ftl.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
ssfdc.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00