kernel.git/drivers/mtd/ubi/build.c, branch linux-2.6.37.y

UBI: preserve corrupted PEBs

2010-10-19T14:19:57Z

Currently UBI erases all corrupted eraseblocks, irrespectively of the nature of corruption: corruption due to power cuts and non-power cut corruption. The former case is OK, but the latter is not, because UBI may destroy potentially important data. With this patch, during scanning, when UBI hits a PEB with corrupted VID header, it checks whether this PEB contains only 0xFF data. If yes, it is safe to erase this PEB and it is put to the 'erase' list. If not, this may be important data and it is better to avoid erasing this PEB. Instead, UBI puts it to the corr list and moves out of the pool of available PEB. IOW, UBI preserves this PEB. Such corrupted PEB lessen the amount of available PEBs. So the more of them we accumulate, the less PEBs are available. The maximum amount of non-power cut corrupted PEBs is 8. This patch is a response to UBIFS problem where reporter (Matthew L. Creech ) observes that UBIFS index points to an unmapped LEB. The theory is that corresponding PEB somehow got corrupted and UBI wiped it. This patch (actually a series of patches) tries to make sure such PEBs are preserved - this would make it is easier to analyze the corruption. Signed-off-by: Artem Bityutskiy

UBI: fix small 80 characters limit style issue

2010-10-19T14:19:55Z

One line was longer than 80 lines, make it shorter. Signed-off-by: Artem Bityutskiy

UBI: do not warn unnecessarily

2010-08-02T04:21:19Z

Currently, when UBI attaches an MTD device and cannot reserve all 1% (by default) of PEBs for bad eraseblocks handling, it prints a warning. However, Matthew L. Creech is not very happy to see this warning, because he did reserve enough of PEB at the beginning, but with time some PEBs became bad. The warning is not necessary in this case. This patch makes UBI print the warning o if this is a new image o of this is used image and the amount of reserved PEBs is only 10% (or less) of the size of the reserved PEB pool. Signed-off-by: Artem Bityutskiy

UBI: init even if MTD device cannot be attached, if built into kernel

2010-05-06T06:12:11Z

UBI can be built into the kernel or be compiled as a kernel module. Further on the command line one can specify MTD devices to be attach to UBI while loading. In the current implementation the UBI driver refuses to load if one of the MTD devices cannot be attached. Consider: 1) UBI compiled into the kernel and 2) a MTD device specified on the command line and 3) this MTD device contains bogus data (for whatever reason). During init UBI tries to attach the MTD device is this fails the whole UBI subsystem isn't initialized. Later the userspace cannot attach any MTD to UBI because UBI isn't loaded. This patch keeps the current behaviour: if UBI is compiled as a module and a MTD device cannot be attached the UBI module cannot be loaded, but changes it for the UBI-is-built-into-the-kernel usecase. If UBI is builtin, a not attachable MTD device doen't stop UBI from initializing. This slightly modifies the behaviour if multiple MTD devices are specified on the command line. Now every MTD device is probed and, if possible, attached, i.e. a faulty MTD device doesn't stop the others from being attached. Artem: tweaked the patch Signed-off-by: Marc Kleine-Budde Signed-off-by: Artem Bityutskiy

UBI: remove reboot notifier

2010-05-03T06:08:13Z

The UBI reboot notifier causes problems with hibernation. Move this functionality into the low-level MTD driver instead. Signed-off-by: Kevin Cernekee Signed-off-by: Artem Bityutskiy

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32Z

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

driver-core: Add attribute argument to class_attribute show/store

2010-03-08T01:04:48Z

Passing the attribute to the low level IO functions allows all kinds of cleanups, by sharing low level IO code without requiring an own function for every piece of data. Also drivers can extend the attributes with own data fields and use that in the low level function. This makes the class attributes the same as sysdev_class attributes and plain attributes. This will allow further cleanups in drivers. Full tree sweep converting all users. Signed-off-by: Andi Kleen Signed-off-by: Greg Kroah-Hartman

UBI: fix attaching error path

2010-02-01T13:16:36Z

In the error path of 'ubi_attach_mtd_dev()' we have a tricky situation: we have to release things differently depending on at which point the failure happening. Namely, if @ubi->dev is not initialized, we have to free everything ourselves. But if it was, we should not free the @ubi object, because it will be freed in the 'dev_release()' function. And we did not get this situation right. This patch introduces additional argument to the 'uif_init()' function. On exit, this argument indicates whether the final 'free(ubi)' will happen in 'dev_release()' or not. So the caller always knows how to properly release the resources. Impact: all memory is now correctly released when UBI fails to attach an MTD device. Signed-off-by: Artem Bityutskiy

UBI: support attaching by MTD character device name

2010-02-01T13:16:36Z

This patch adds a capability to attach MTD devices by their character device paths. For example, one can do: $ modprobe ubi mtd=/dev/mtd0 to attach /dev/mtd0. Signed-off-by: Artem Bityutskiy

UBI: mark few variables as __initdata

2010-02-01T13:16:36Z

The @mtd_devs and @mtd_dev_param variables are used only during the initialization, and all functions that use the variables have the __init prefix. This means we can safely mark the variables as __initdata, which is a tiny optimization. Impact: tiny RAM consumption optimization when UBI is used as a kernel module. Signed-off-by: Artem Bityutskiy