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2011-07-04UBIFS: switch self-check knobs to debugfsArtem Bityutskiy1-26/+0
UBIFS has many built-in self-check functions which can be enabled using the debug_chks module parameter or the corresponding sysfs file (/sys/module/ubifs/parameters/debug_chks). However, this is not flexible enough because it is not per-filesystem. This patch moves this to debugfs interfaces. We already have debugfs support, so this patch just adds more debugfs files. While looking at debugfs support I've noticed that it is racy WRT file-system unmount, and added a TODO entry for that. This problem has been there for long time and it is quite standard debugfs PITA. The plan is to fix this later. This patch is simple, but it is large because it changes many places where we check if a particular type of checks is enabled or disabled. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: lessen amount of debugging check typesArtem Bityutskiy1-3/+1
We have too many different debugging checks - lessen the amount by merging all index-related checks into one. At the same time, move the "force in-the-gap" test to the "index checks" class, because it is too heavy for the "general" class. This patch merges TNC, Old index, and Index size check and calles this just "index checks". Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-23UBIFS: switch to dynamic printksArtem Bityutskiy1-23/+2
Switch to debugging using dynamic printk (pr_debug()). There is no good reason to carry custom debugging prints if there is so cool and powerful generic dynamic printk infrastructure, see Documentation/dynamic-debug-howto.txt. With dynamic printks we can switch on/of individual prints, per-file, per-function and per format messages. This means that instead of doing old-fashioned echo 1 > /sys/module/ubifs/parameters/debug_msgs to enable general messages, we can do: echo 'format "UBIFS DBG gen" +ptlf' > control to enable general messages and additionally ask the dynamic printk infrastructure to print process ID, line number and function name. So there is no reason to keep UBIFS-specific crud if there is more powerful generic thing. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: make force in-the-gaps to be a general self-checkArtem Bityutskiy1-1/+0
UBIFS can force itself to use the 'in-the-gaps' commit method - the last resort method which is normally invoced very very rarely. Currently this "force int-the-gaps" debugging feature is a separate test mode. But it is a bit saner to make it to be the "general" self-test check instead. This patch is just a clean-up which should make the debugging code look a bit nicer and easier to use - we have way too many debugging options. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-11UBIFS: do not check data crc by defaultArtem Bityutskiy1-2/+2
Change the default UBIFS behavior WRT data CRC checking. Currently, UBIFS checks data CRC when reading, which slows it down quite a bit, and this is the default option. However, it looks like in average user does not need this feature and would prefer faster read speed over extra reliability. And this seems to be de-facto standard that file-systems do not check data CRC every time they read from the media. Thus, make UBIFS default behavior so that it does not check data CRC. This corresponds to the no_chk_data_crc mount option. Those users who need extra protection can always enable it using the chk_data_crc option. Please, read more information about this feature here: http://www.linux-mtd.infradead.org/doc/ubifs.html#L_checksumming Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2009-01-29UBIFS: remove fast unmountingArtem Bityutskiy1-7/+0
This UBIFS feature has never worked properly, and it was a mistake to add it because we simply have no use-cases. So, lets still accept the fast_unmount mount option, but ignore it. This does not change much, because UBIFS commit in sync_fs anyway, and sync_fs is called while unmounting. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-31UBIFS: fix numerous spelling mistakesArtem Bityutskiy1-3/+3
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-12-03UBIFS: introduce compression mount optionsArtem Bityutskiy1-0/+3
It is very handy to be able to change default UBIFS compressor via mount options. Introduce -o compr=<name> mount option support. Currently only "none", "lzo" and "zlib" compressors are supported. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-09-30UBIFS: add no_chk_data_crc mount optionAdrian Hunter1-0/+6
UBIFS read performance can be improved by skipping the CRC check when data nodes are read. This option can be used if the underlying media is considered to be highly reliable. Note that CRCs are always checked for metadata. Read speed on Arm platform with OneNAND goes from 19 MiB/s to 27 MiB/s with data CRC checking disabled. Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-09-30UBIFS: add bulk-read facilityAdrian Hunter1-0/+3
Some flash media are capable of reading sequentially at faster rates. UBIFS bulk-read facility is designed to take advantage of that, by reading in one go consecutive data nodes that are also located consecutively in the same LEB. Read speed on Arm platform with OneNAND goes from 17 MiB/s to 19 MiB/s. Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>
2008-08-13Documentation: fix typo in ubifs.txtSebastian Siewior1-1/+1
Signed-off-by: Sebastian Siewior <bigeasy@linutronix.de> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2008-07-15UBIFS: add brief documentationArtem Bityutskiy1-0/+164
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>