linux/drivers/mtd
Shmulik Ladkani 37f758a036 UBI: limit amount of reserved eraseblocks for bad PEB handling
The existing mechanism of reserving PEBs for bad PEB handling has two
flaws:
- It is calculated as a percentage of good PEBs instead of total PEBs.
- There's no limit on the amount of PEBs UBI reserves for future bad
  eraseblock handling.

This patch changes the mechanism to overcome these flaws.

The desired level of PEBs reserved for bad PEB handling (beb_rsvd_level)
is set to the maximum expected bad eraseblocks (bad_peb_limit) minus the
existing number of bad eraseblocks (bad_peb_count).

The actual amount of PEBs reserved for bad PEB handling is usually set
to the desired level (but in some circumstances may be lower than the
desired level, e.g. when attaching to a device that has too few
available PEBs to satisfy the desired level).

In the case where the device has too many bad PEBs (above the expected
limit), then the desired level, and the actual amount of PEBs reserved
are set to zero. No PEBs will be set aside for future bad eraseblock
handling - even if some PEBs are made available (e.g. by shrinking a
volume).
If another PEB goes bad, and there are available PEBs, then the
eraseblock will be marked bad (consuming one available PEB). But if
there are no available PEBs, ubi will go into readonly mode.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
2012-09-04 09:38:58 +03:00
..
chips mtd: cfi_cmdset_0002: Slight cleanup of fixup messages 2012-05-13 23:34:36 -05:00
devices - More robust parsing especially of xattr data in JFFS2 2012-06-01 16:55:42 -07:00
lpddr mtd: lpddr: replace open-coded ARRAY_SIZE with macro 2012-05-13 22:47:31 -05:00
maps mtd/uclinux: Use generic __bss_stop instead of _ebss 2012-06-27 09:59:43 +02:00
nand Merge branch 'testing/new-warnings' into fixes 2012-08-10 12:28:57 +02:00
onenand mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-13 23:14:23 -05:00
tests mtd: introduce mtd_can_have_bb helper 2012-01-09 18:26:24 +00:00
ubi UBI: limit amount of reserved eraseblocks for bad PEB handling 2012-09-04 09:38:58 +03:00
afs.c mtd: introduce mtd_read interface 2012-01-09 18:25:19 +00:00
ar7part.c mtd: introduce mtd_read interface 2012-01-09 18:25:19 +00:00
bcm63xxpart.c mtd: bcm63xxpart: handle Broadcom partition order 2012-05-13 22:55:03 -05:00
cmdlinepart.c mtd: cmdlinepart: fix commentary 2012-05-13 23:03:36 -05:00
ftl.c mtd: do not use mtd->sync directly 2012-01-09 18:26:21 +00:00
inftlcore.c mtd: add leading underscore to all mtd functions 2012-03-27 00:20:01 +01:00
inftlmount.c mtd: introduce mtd_block_markbad interface 2012-01-09 18:25:48 +00:00
Kconfig mtd: of_parts: fix breakage in Kconfig 2012-06-01 20:06:59 +01:00
Makefile mtd: maps: bcm963xx-flash: make CFE partition parsing an mtd parser 2012-01-09 18:15:31 +00:00
mtd_blkdevs.c mtd: mtdblock: call mtd_sync() only if opened for write 2012-03-27 00:11:11 +01:00
mtdblock_ro.c mtd: introduce mtd_write interface 2012-01-09 18:25:20 +00:00
mtdblock.c mtd: mtdblock: call mtd_sync() only if opened for write 2012-03-27 00:11:11 +01:00
mtdchar.c mtd: fix oops in dataflash driver 2012-05-07 20:29:50 +01:00
mtdconcat.c mtd: unify initialization of erase_info->fail_addr 2012-03-27 01:02:24 +01:00
mtdcore.c mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-13 23:14:23 -05:00
mtdcore.h mtd: hide parse_mtd_partitions 2011-09-11 15:02:13 +03:00
mtdoops.c kmsg - kmsg_dump() use iterator to receive log buffer content 2012-06-15 14:53:59 -07:00
mtdpart.c mtd: driver _read() returns max_bitflips; mtd_read() returns -EUCLEAN 2012-05-13 23:14:23 -05:00
mtdsuper.c VFS: Pass mount flags to sget() 2012-07-14 16:38:34 +04:00
mtdswap.c mtd: do not use mtd->block_markbad directly 2012-01-09 18:26:26 +00:00
nftlcore.c mtd: nftlcore: remove out-of-date and now irrelevant piece of code 2012-03-27 00:24:03 +01:00
nftlmount.c mtd: introduce mtd_block_markbad interface 2012-01-09 18:25:48 +00:00
ofpart.c mtd: ofpart: add ofoldpart alias 2011-09-11 15:02:14 +03:00
redboot.c mtd: redboot: remove useless code 2012-03-27 00:24:14 +01:00
rfd_ftl.c mtd: do not use mtd->sync directly 2012-01-09 18:26:21 +00:00
sm_ftl.c mtd: sm_ftl: fix typo in major number. 2012-03-27 01:01:26 +01:00
sm_ftl.h mtd: sm_ftl: cosmetic, use bool when possible 2010-10-25 01:33:08 +01:00
ssfdc.c mtd: introduce mtd_block_isbad interface 2012-01-09 18:25:47 +00:00