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* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h 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 <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* UBI: add write checkingArtem Bityutskiy2010-02-011-0/+70
| | | | | | | | | | Add an extra debugging check function which validates writes. After every write it reads the data back, compares it with the original data, and complains if they mismatch. Useful for debugging. No-op if extra debugging checks are disabled. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: simplify debugging return codesArtem Bityutskiy2010-02-011-25/+25
| | | | | | | | | | | UBI debugging functions were a little bit over-engineered and returned more error codes than needed, and the callers had to do useless checks. Simplify the return codes. Impact: only debugging code is affected, which means that for non-developers this is a no-op patch. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: improve NOR flash erasure quirkArtem Bityutskiy2009-08-141-15/+31
| | | | | | | | | | | More testing of NOR flash against power cuts showed that sometimes eraseblocks may be unwritable, and we cannot really invalidate them before erasure. But in this case the eraseblock probably contains garbage anyway, and we do not have to invalidate the headers. This assumption might be not true, but this is at least what I have observed. So if we cannot invalidate the headers, we make sure that the PEB does not contain valid VID header. If this is true, everything is fine, otherwise we panic.
* UBI: introduce flash dump helperArtem Bityutskiy2009-08-141-0/+1
| | | | | | | | Useful for debugging problems, compiled in only if UBI debugging is enabled. This patch also makes the UBI writing function dump the flash if it fails to write. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: amend NOR flash pre-erase quirkArtem Bityutskiy2009-08-141-4/+4
| | | | | | | | | | | | | In case of NOR flash, UBI zeroes EC and VID headers' magic, in order to detect interrupted erasures. It first zeroes out the EC magic, then VID magic. However, if a power cut happens in between, we'll end up with a corrupted EC header and a valid VID header, in which case UBI accepts the PEB, but prints a warning. This patch makes sure we first zero out the VID magic, then the EC magic, not vice versa. This is just a small amendment to prevent warning messages. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix compilation warningsArtem Bityutskiy2009-07-081-3/+3
| | | | | | | | | The recent "UBI: fix NOR flash recovery" introduced compilation warnings which were immediately spotted by our linux-next keeper. This patch fixes them. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix NOR flash recoveryArtem Bityutskiy2009-07-071-2/+56
| | | | | | | | | | | | | | | | This commit fixes NOR flash recovery issues observed with Spansion S29GL512N NOR. When NOR erases, it first fills PEBs with zeroes, then sets all bytes to 0xFF. Filling with zeroes starts from the end of the PEB. And when power is cut, this results in PEBs containing correct EC and VID headers but corrupted with zeros at the end. This confuses UBI and it mistakinly accepts these PEBs and associate them with LEBs. Fis this issue by zeroing EC and VID magics before erasing PEBs, to make UBI later refuse zem. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: nicify image sequence number handlingArtem Bityutskiy2009-07-051-12/+2
| | | | | | | | | Move the image seq. number handling from I/O level to the scanning lever, where it really belongs to. Move the @image_seq_set variable to the @struct ubi_scan_info structure, which exists only during scanning. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: add image sequence number to EC headerAdrian Hunter2009-07-051-2/+13
| | | | | | | | | | | An image sequence number is added to the UBI erase-counter header to be able determine if the root file system contains a mixture of old and new images (because the flashing failed to complete). A change to nolo is also needed for this to take effect. Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: remove bogus debugging checksArtem Bityutskiy2009-07-051-87/+0
| | | | | | | | | | | | | The 'paranoid_check_empty()' is bogus because, which is easilly seen on NOR flash, which has long erase cycles, and which may easilly end-up with half-erased eraseblocks. In this case the paranoid check fails. I is just wrong to assume that PEBs which do not have EC headers always contain all 0xFF. Such assumption should not be made on the I/O level, which is quite low. Thus, just kill the check. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: add empty eraseblocks verificationArtem Bityutskiy2009-07-051-10/+7
| | | | | | | | This patch adds code which makes sure eraseblocks contain all 0xFF bytes before starting using them. The verification is done only when debugging checks are enabled. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix multiple spelling typosArtem Bityutskiy2009-06-101-1/+1
| | | | | | | Some of the typos were indicated by Adrian Hunter, some by 'aspell'. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix races in I/O debugging checksArtem Bityutskiy2009-05-181-7/+73
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | When paranoid checs are enabled, the 'io_paral' test from the 'mtd-utils' package fails. The symptoms are: UBI error: paranoid_check_all_ff: flash region at PEB 3973:512, length 15872 does not contain all 0xFF bytes UBI error: paranoid_check_all_ff: paranoid check failed for PEB 3973 UBI: hex dump of the 512-16384 region It turned out to be a bug in the checking function. Suppose there are 2 tasks - A and B. Task A is the wear-levelling working ('wear_leveling_worker()'). It is reading the VID header to find which LEB this PEB belongs to. Say, task A is reading header of PEB X. Suppose PEB X is unmapped, and has no VID header. Task B is trying to write to PEB X. Task A: in 'ubi_io_read_vid_hdr()': reads the VID header from PEB X. The read data contain all 0xFF bytes. Task B: writes VID header and some data to PEB X Task A: assumes PEB X is empty, calls 'paranoid_check_all_ff()', which fails. The solution for this problem is to make 'paranoid_check_all_ff()' re-read the VID header, re-check it, and only if it is not there, check the rest. This now implemented by the 'paranoid_check_empty()' function. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* trivial: fix then -> than typos in comments and documentationFrederik Schwarzer2009-01-061-1/+1
| | | | | | | - (better, more, bigger ...) then -> (...) than Signed-off-by: Frederik Schwarzer <schwarzerf@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
* UBI: fix checkpatch.pl warningsArtem Bityutskiy2008-12-281-1/+1
| | | | | | Just minor indentation and "over 80 characters" fixes. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix warnings when debugging is enabledArtem Bityutskiy2008-12-031-8/+18
| | | | | | | | | | | | | | | | | | | The 'ubi_io_read_vid_hdr()' and 'ubi_io_read_ec_hdr()' function have the 'verbose' argument which controls whether they should print a warning if the VID/EC header was not found or was corrupted. Some callers require the headers to be OK, and pass 1. Some allow a corrupted/not present header, and pass 0. if (UBI_IO_DEBUG) verbose = 1; And UBI_IO_DEBUG is 1 if CONFIG_MTD_UBI_DEBUG_MSG_BLD is true. So in this case the warning is printed all the time. This confuses people. Thus, do not print the messages as warnings if UBI_IO_DEBUG is true, but print them as debugging messages instead. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix kernel-doc errors and warningsArtem Bityutskiy2008-07-241-4/+2
| | | | | | | No functional changes, just tweak comments to make kernel-doc work fine and stop complaining. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix checkpatch.pl errors and warningsArtem Bityutskiy2008-07-241-4/+4
| | | | | | | | Just out or curiousity ran checkpatch.pl for whole UBI, and discovered there are quite a few of stylistic issues. Fix them. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: rework scrubbing messagesArtem Bityutskiy2008-07-241-1/+7
| | | | | | | | If bit-flips happen often, UBI prints to many messages. Lessen the amount by only printing the messages when the PEB has been scrubbed. Also, print torturing messages. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix and re-work debugging stuffArtem Bityutskiy2008-07-241-2/+2
| | | | Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: amend commentariesArtem Bityutskiy2008-07-241-11/+11
| | | | | | | Hch asked not to use "unit" for sub-systems, let it be so. Also some other commentaries modifications. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: be verbose when debuggin is enabledArtem Bityutskiy2008-04-171-0/+4
| | | | | | | Make I/O function to be always verbose when about CRC errors and magic number errors when I/O debugging is enabled. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix error code in ubi_io_read()Artem Bityutskiy2007-12-261-0/+10
| | | | | | | | | | | | | | | | | | | | When NAND detects an ECC error, it returns -EBADMSG. It does not stop reading requested data if one page has an ECC error, it keeps going and reads all the requested data. If it fails to read all the data, it does not return -EBADMSG, but returns the error code which reflects the reason of the failure. But some drivers may have bugs (e.g., OneNAND had) and stop reading after the first ECC error, so it returns -EBADMSG. In turn, UBI propagates this up to the caller. The caller will treat this as "all the requested data was read, but there was an ECC error". So we change the error code to -EIO if it is -EBADMSG and the read length is less then the requested length. We also add an assertion, so if UBI debugging is enabled, UBI will bug. Pointed-to-by: Adrian Hunter <ext-adrian.hunter@nokia.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: use byte hexdumpArtem Bityutskiy2007-10-141-1/+1
| | | | | | More handy since word hexdump prints in host endian. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: do not use vmalloc on I/O pathArtem Bityutskiy2007-10-141-37/+29
| | | | | | | | | | | Similar reason as in case of the previous patch: it causes deadlocks if a filesystem with writeback support works on top of UBI. So pre-allocate needed buffers when attaching MTD device. We also need mutexes to protect the buffers, but they do not cause much contantion because they are used in recovery, torture, and WL copy routines, which are called seldom. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: allocate memory with GFP_NOFSArtem Bityutskiy2007-10-141-2/+2
| | | | | | | | | | | Use GFP_NOFS flag when allocating memory on I/O path, because otherwise we may deadlock the filesystem which works on top of us. We observed the deadlocks with UBIFS. Example: VFS->FS lock a lock->UBI->kmalloc()->VFS writeback->FS locks the same lock again. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: use linux print_hex_dump(), not home-grown oneArtem Bityutskiy2007-10-141-1/+1
| | | | Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: add more printsArtem Bityutskiy2007-10-141-1/+4
| | | | | | | I hit those situations and found out lack of print messages. Add more prints when erase problems occur. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix commentsArtem Bityutskiy2007-07-181-3/+3
| | | | Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: fix signed-unsigned multiplicationBrijesh Singh2007-07-181-1/+1
| | | | | | | | | There is signed multiplication assigned to unsigned ei.addr in io.c. This causes wrong addresses for big multiplication.This patch solves the problem. Signed-off-by: Brijesh Singh <brijesh.s.singh@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: kill homegrown endian macrosChristoph Hellwig2007-07-181-23/+23
| | | | | | | | Kill UBI's homegrown endianess handling and replace it with the standard kernel endianess handling. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: use vmalloc for large buffersArtem Bityutskiy2007-07-181-5/+6
| | | | | | | UBI allocates temporary buffers of PEB size, which may be 256KiB. Use vmalloc instead of kmalloc for such big temporary buffers. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* UBI: Unsorted Block ImagesArtem B. Bityutskiy2007-04-271-0/+1259
UBI (Latin: "where?") manages multiple logical volumes on a single flash device, specifically supporting NAND flash devices. UBI provides a flexible partitioning concept which still allows for wear-levelling across the whole flash device. In a sense, UBI may be compared to the Logical Volume Manager (LVM). Whereas LVM maps logical sector numbers to physical HDD sector numbers, UBI maps logical eraseblocks to physical eraseblocks. More information may be found at http://www.linux-mtd.infradead.org/doc/ubi.html Partitioning/Re-partitioning An UBI volume occupies a certain number of erase blocks. This is limited by a configured maximum volume size, which could also be viewed as the partition size. Each individual UBI volume's size can be changed independently of the other UBI volumes, provided that the sum of all volume sizes doesn't exceed a certain limit. UBI supports dynamic volumes and static volumes. Static volumes are read-only and their contents are protected by CRC check sums. Bad eraseblocks handling UBI transparently handles bad eraseblocks. When a physical eraseblock becomes bad, it is substituted by a good physical eraseblock, and the user does not even notice this. Scrubbing On a NAND flash bit flips can occur on any write operation, sometimes also on read. If bit flips persist on the device, at first they can still be corrected by ECC, but once they accumulate, correction will become impossible. Thus it is best to actively scrub the affected eraseblock, by first copying it to a free eraseblock and then erasing the original. The UBI layer performs this type of scrubbing under the covers, transparently to the UBI volume users. Erase Counts UBI maintains an erase count header per eraseblock. This frees higher-level layers (like file systems) from doing this and allows for centralized erase count management instead. The erase counts are used by the wear-levelling algorithm in the UBI layer. The algorithm itself is exchangeable. Booting from NAND For booting directly from NAND flash the hardware must at least be capable of fetching and executing a small portion of the NAND flash. Some NAND flash controllers have this kind of support. They usually limit the window to a few kilobytes in erase block 0. This "initial program loader" (IPL) must then contain sufficient logic to load and execute the next boot phase. Due to bad eraseblocks, which may be randomly scattered over the flash device, it is problematic to store the "secondary program loader" (SPL) statically. Also, due to bit-flips it may become corrupted over time. UBI allows to solve this problem gracefully by storing the SPL in a small static UBI volume. UBI volumes vs. static partitions UBI volumes are still very similar to static MTD partitions: * both consist of eraseblocks (logical eraseblocks in case of UBI volumes, and physical eraseblocks in case of static partitions; * both support three basic operations - read, write, erase. But UBI volumes have the following advantages over traditional static MTD partitions: * there are no eraseblock wear-leveling constraints in case of UBI volumes, so the user should not care about this; * there are no bit-flips and bad eraseblocks in case of UBI volumes. So, UBI volumes may be considered as flash devices with relaxed restrictions. Where can it be found? Documentation, kernel code and applications can be found in the MTD gits. What are the applications for? The applications help to create binary flash images for two purposes: pfi files (partial flash images) for in-system update of UBI volumes, and plain binary images, with or without OOB data in case of NAND, for a manufacturing step. Furthermore some tools are/and will be created that allow flash content analysis after a system has crashed.. Who did UBI? The original ideas, where UBI is based on, were developed by Andreas Arnez, Frank Haverkamp and Thomas Gleixner. Josh W. Boyer and some others were involved too. The implementation of the kernel layer was done by Artem B. Bityutskiy. The user-space applications and tools were written by Oliver Lohmann with contributions from Frank Haverkamp, Andreas Arnez, and Artem. Joern Engel contributed a patch which modifies JFFS2 so that it can be run on a UBI volume. Thomas Gleixner did modifications to the NAND layer. Alexander Schmidt made some testing work as well as core functionality improvements. Signed-off-by: Artem B. Bityutskiy <dedekind@linutronix.de> Signed-off-by: Frank Haverkamp <haver@vnet.ibm.com>
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