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path: root/fs/ubifs/debug.c
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2012-06-27UBIFS: correct usage of IS_ENABLED()Brian Norris
Commit "818039c UBIFS: fix debugfs-less systems support" fixed one regression but introduced a different regression - the debugfs is now always compiled out. Root cause: IS_ENABLED() arguments should be used with the CONFIG_* prefix. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-06-07UBIFS: fix debugfs-less systems supportArtem Bityutskiy
Commit "f70b7e5 UBIFS: remove Kconfig debugging option" broke UBIFS and it refuses to initialize if debugfs (CONFIG_DEBUG_FS) is disabled. I incorrectly assumed that debugfs files creation function will return success if debugfs is disabled, but they actually return -ENODEV. This patch fixes the issue. Reported-by: Paul Parsons <lost.distance@yahoo.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Tested-by: Paul Parsons <lost.distance@yahoo.com>
2012-05-20UBI: Kill data type hintRichard Weinberger
We do not need this feature and to our shame it even was not working and there was a bug found very recently. -- Artem Bityutskiy Without the data type hint UBI2 (fastmap) will be easier to implement. Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-16UBIFS: get rid of dbg_errArtem Bityutskiy
This patch removes the 'dbg_err()' macro and we now use 'ubifs_err()' instead. The idea of 'dbg_err()' was to compile out some error message to make the binary a bit smaller - but I think it was a bad idea. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-16UBIFS: remove Kconfig debugging optionArtem Bityutskiy
Have the debugging stuff always compiled-in instead. It simplifies maintanance a lot. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-16UBIFS: rename dumping functionsArtem Bityutskiy
This commit re-names all functions which dump something from "dbg_dump_*()" to "ubifs_dump_*()". This is done for consistency with UBI and because this way it will be more logical once we remove the debugging sompilation option. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-05-16UBIFS: get rid of dbg_dump_stackArtem Bityutskiy
In case of errors we almost always need the stack dump - it makes no sense to compile it out. Remove the 'dbg_dump_stack()' function completely. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-02-29UBIFS: make the dbg_lock spinlock staticArtem Bityutskiy
Remove the usage of the 'dbg_lock' spinlock from 'dbg_err()' and make it static. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-02-29UBIFS: increase dumps loglevelArtem Bityutskiy
Most of the time we use the dumping function to dump something in case of error. We use 'KERN_DEBUG' printk level, and the drawback is that users do not see them in the console, while they see the other error messages in the console. The result is that they send bug reports which does not contain a lot of useful information. This patch changes the printk level of the dump functions to 'KERN_ERR' to correct the situation. I documented it in the MTD web site that people have to send the 'dmesg' output when submitting bug reposts - it did not help. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-01-13UBIFS: fix key printingArtem Bityutskiy
Before commit 56e46742e846e4de167dde0e1e1071ace1c882a5 we have had locking around all printing macros and we could use static buffers for creating key strings and printing them. However, now we do not have that locking and we cannot use static buffers. This commit removes the old DBGKEY() macros and introduces few new helper macros for printing debugging messages plus a key at the end. Thankfully, all the messages are already structures in a way that the key is printed in the end. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2012-01-13UBIFS: use snprintf instead of sprintf when printing keysArtem Bityutskiy
Switch to 'snprintf()' which is more secure and reliable. This is also a preparation to the subsequent key printing fixes. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
2011-08-22UBIFS: introduce a helper to dump scanning infoArtem Bityutskiy
This commit adds 'dbg_dump_sleb()' helper function to dump scanning information. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
2011-07-04UBIFS: improve power cut emulation testingArtem Bityutskiy
This patch cleans-up and improves the power cut testing: 1. Kill custom 'simple_random()' function and use 'random32()' instead. 2. Make timeout larger 3. When cutting the buffer - fill the end with random data sometimes, not only with 0xFFs. 4. Some times cut in the middle of the buffer, not always at the end. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: rename recovery testing variablesArtem Bityutskiy
Since the recovery testing is effectively about emulating power cuts by UBIFS, use "power cut" as the base term for all the related variables and name them correspondingly. This is just a minor clean-up for the sake of readability. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: remove custom list of superblocksArtem Bityutskiy
This is a clean-up of the power-cut emulation code - remove the custom list of superblocks which we maintained to find the superblock by the UBI volume descriptor. We do not need that crud any longer, because now we can get the superblock as a function argument. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: stop re-defining UBI operationsArtem Bityutskiy
Now when we use UBIFS helpers for all the I/O, we can remove the horrible hack of re-defining UBI I/O functions. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: remove unused and unneeded debugging functionArtem Bityutskiy
This patch contains several minor clean-up and preparational cahnges. 1. Remove 'dbg_read()', 'dbg_write()', 'dbg_change()', and 'dbg_leb_erase()' functions as they are not used. 2. Remove 'dbg_leb_read()' and 'dbg_is_mapped()' as they are not really needed, it is fine to let reads go through in failure mode. 3. Rename 'offset' argument to 'offs' to be consistent with the rest of UBIFS code. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: add global debugfs knobsArtem Bityutskiy
Now we have per-FS (superblock) debugfs knobs, but they have one drawback - you have to first mount the FS and only after this you can switch self-checks on/off. But often we want to have the checks enabled during the mount. Introduce global debugging knobs for this purpose. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: introduce debugfs helpersArtem Bityutskiy
Separate out pieces of code from the debugfs file read/write functions and create separate 'interpret_user_input()'/'provide_user_output()' helpers. These helpers will be needed in one of the following patches, so this is just a preparational change. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: re-arrange debugging code a bitArtem Bityutskiy
Move 'dbg_debugfs_init()' and 'dbg_debugfs_exit()' functions which initialize debugfs for whole UBIFS subsystem below the code which initializes debugfs for a particular UBIFS instance. And do the same for 'ubifs_debugging_init()' and 'ubifs_debugging_exit()' functions. This layout is a bit better for the next patches, so this is just a preparation. Also, rename 'open_debugfs_file()' into 'dfs_file_open()' for consistency. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: be more informative in failure modeArtem Bityutskiy
When we are testing UBIFS recovery, it is better to print in which eraseblock we are going to fail. Currently UBIFS prints it only if recovery debugging messages are enabled, but this is not very practical. So change 'dbg_rcvry()' messages to 'ubifs_warn()' messages. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: switch self-check knobs to debugfsArtem Bityutskiy
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 Bityutskiy
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>
2011-07-04UBIFS: introduce helper functions for debugging checks and testsArtem Bityutskiy
This patch introduces helper functions for all debugging checks, so instead of doing if (!(ubifs_chk_flags & UBIFS_CHK_GEN)) we now do if (!dbg_is_chk_gen(c)) This is a preparation to further changes where the flags will go away, and we'll need to only change the helper functions, but the code which utilizes them won't be touched. At the same time this patch removes 'dbg_force_in_the_gaps()', 'dbg_force_in_the_gaps_enabled()', and dbg_failure_mode helpers for consistency. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: amend debugging inode size check function prototypeArtem Bityutskiy
Add 'const struct ubifs_info *c' parameter to 'dbg_check_synced_i_size()' function because we'll need it in the next patch when we switch to debugfs. So this patch is just a preparation. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: rename dbg_check_dir_size functionArtem Bityutskiy
Since this function is not only about size checking, rename it to 'dbg_check_dir()'. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: improve inode dumping functionArtem Bityutskiy
Teach 'dbg_dump_inode()' dump directory entries for directory inodes. This requires few additional changes: 1. The 'c' argument of 'dbg_dump_inode()' cannot be const any more. 2. Users of 'dbg_dump_inode()' should not have 'tnc_mutex' locked. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-07-04UBIFS: lessen the size of debugging info data structureArtem Bityutskiy
This patch lessens the 'struct ubifs_debug_info' size by 90 bytes by allocating less bytes for the debugfs root directory name. It introduces macros for the name patter an length instead of hard-coding 100 bytes. It also makes UBIFS use 'snprintf()' and teaches it to gracefully catch situations when the name array is too short. Additionally, this patch makes 2 unrelated changes - I just thought they do not deserve separate commits: simplifies 'ubifs_assert()' for non-debugging case and makes 'dbg_debugfs_init()' properly verify debugfs return code which may be an error code or NULL, so we should you 'IS_ERR_OR_NULL()' instead of 'IS_ERR()'. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-23UBIFS: switch to dynamic printksArtem Bityutskiy
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>
2011-05-16UBIFS: add a superblock flag for free space fix-upMatthew L. Creech
The 'space_fixup' flag can be set in the superblock of a new filesystem by mkfs.ubifs to indicate that any eraseblocks with free space remaining should be fixed-up the first time it's mounted (after which the flag is un-set). This means that the UBIFS image has been flashed by a "dumb" flasher and the free space has been actually programmed (writing all 0xFFs), so this free space cannot be used. UBIFS fixes the free space up by re-writing the contents of all LEBs with free space using the atomic LEB change UBI operation. Artem: improved commit message, add some more commentaries to the code. Signed-off-by: Matthew L. Creech <mlcreech@gmail.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: fix debugging FS checking failureArtem Bityutskiy
When the debugging self-checks are enabled, we go trough whole file-system after mount and check/validate every single node referred to by the index. This is implemented by the 'dbg_check_filesystem()' function. However, this function fails if we mount "unclean" file-system, i.e., if we mount the file-system after a power cut. It fails with the following symptoms: UBIFS DBG (pid 8171): ubifs_recover_size: ino 937 size 3309925 -> 3317760 UBIFS: recovery deferred UBIFS error (pid 8171): check_leaf: data node at LEB 1000:0 is not within inode size 3309925 The reason of failure is that recovery fixed up the inode size in memory, but not on the flash so far. So the value on the flash is incorrect so far, and would be corrected when we re-mount R/W. But 'check_leaf()' ignores this fact and tries to validate the size of the on-flash inode, which is incorrect, so it fails. This patch teaches the checking code to look at the VFS inode cache first, and if there is the inode in question, use that inode instead of the inode on the flash media. This fixes the issue. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: do not change debugfs file positionArtem Bityutskiy
This patch is a tiny improvement which removes few bytes of code. UBIFS debugfs files are non-seekable and the file position is ignored, so do not increase it in the write handler. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: fix oops in lprops dump functionArtem Bityutskiy
The 'dbg_dump_lprop()' is trying to detect journal head LEBs when printing, so it looks at the write-buffers. However, if we are in R/O mode, we de-allocate the write-buffers, so 'dbg_dump_lprop()' oopses. This patch fixes the issue. Note, this patch is not critical, it is only about the debugging code path, and it is unlikely that anyone but UBIFS developers would ever hit this issue. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: use EROFS when emulating failuresArtem Bityutskiy
When the debugging failure emulation is enabled and UBIFS decides to emulate an I/O error, it uses EIO error code. In which case UBIFS switches into R/O mode later on. The for the user-space is that when a failure is emulated, the file-system sometimes returns EIO and sometimes EROFS. This makes it more difficult to implement user-space tests for the failure mode. Let's be consistent and return EROFS in all the cases. This patch is an improvement for the debugging code and does not affect the functionality at all. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: make force in-the-gaps to be a general self-checkArtem Bityutskiy
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>
2011-05-13UBIFS: improve space checking debugging featureArtem Bityutskiy
This patch improves the 'dbg_check_space_info()' function which checks whether the amount of space before re-mounting and after re-mounting is the same (remounting from R/O to R/W modes and vice-versa). The problem is that 'dbg_check_space_info()' does not save the budgeting information before re-mounting, so when an error is reported, we do not know why the amount of free space changed. This patches makes the following changes: 1. Teaches 'dbg_dump_budg()' function to accept a 'struct ubifs_budg_info' argument and print out the this argument. This way we may ask it to print any saved budgeting info, no only the current one. 2. Accordingly changes all the callers of 'dbg_dump_budg()' to comply with the changed interface. 3. Introduce a 'saved_bi' (saved budgeting info) field to 'struct ubifs_debug_info' and save the budgeting info before re-mounting there. 4. Change 'dbg_check_space_info()' and make it print both old and new budgeting information. 5. Additionally, save 'c->igx_gc_cnt' and print it if and error happens. This value contributes to the amount of free space, so we have to print it. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: rearrange the budget dumpArtem Bityutskiy
Re-arrange the budget dump and make sure we first dump all the 'struct ubifs_budg_info' fields, and then the other information. Additionally, print the 'uncommitted_idx' variable. This change is required for to the following dumping function enhancement where it will be possible to dump saved 'struct ubifs_budg_info' objects, not only the current one. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: simplify dbg_dump_budg calling conventionsArtem Bityutskiy
The current 'dbg_dump_budg()' calling convention is that the 'c->space_lock' spinlock is held. However, none of the callers actually use it from contects which have 'c->space_lock' locked, so all callers have to explicitely lock and unlock the spinlock. This is not very sensible convention. This patch changes it and makes 'dbg_dump_budg()' lock the spinlock instead of imposing this to the callers. This simplifies the code a little. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: introduce a separate structure for budgeting infoArtem Bityutskiy
This patch separates out all the budgeting-related information from 'struct ubifs_info' to 'struct ubifs_budg_info'. This way the code looks a bit cleaner. However, the main driver for this is that we want to save budgeting information and print it later, so a separate data structure for this is helpful. This patch is a preparation for the further debugging output improvements. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: fix minor stylistic issuesArtem Bityutskiy
Fix several minor stylistic issues: * lines longer than 80 characters * space before closing parenthesis ')' * spaces in the indentations Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-05-13UBIFS: make debugfs files non-seekableArtem Bityutskiy
Turn the debufs files UBIFS maintains into non-seekable. Indeed, none of them is supposed to be seek'ed. Do this by making the '.lseek()' handler to be 'no_llseek()' and by using 'nonseekable_open()' in the '.open()' operation. This does mean an API break but this debugging API is only used by a couple of test scripts which do not rely in the 'llseek()' operation. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-04-05UBIFS: fix debugging failure in dbg_check_space_infoArtem Bityutskiy
This patch fixes a debugging failure with which looks like this: UBIFS error (pid 32313): dbg_check_space_info: free space changed from 6019344 to 6022654 The reason for this failure is described in the comment this patch adds to the code. But in short - 'c->freeable_cnt' may be different before and after re-mounting, and this is normal. So the debugging code should make sure that free space calculations do not depend on 'c->freeable_cnt'. A similar issue has been reported here: http://lists.infradead.org/pipermail/linux-mtd/2011-April/034647.html This patch should fix it. For the -stable guys: this patch is only relevant for kernels 2.6.30 onwards. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Cc: stable@kernel.org [2.6.30+]
2011-04-05UBIFS: fix error path in dbg_debugfs_init_fsArtem Bityutskiy
The debug interface is substandard and on error returns either NULL or an error code packed in the pointer. So using "IS_ERR" for the pointers returned by debugfs function is incorrect. Instead, we should use IS_ERR_OR_NULL. This path is an improved vestion of the original patch from Phil Carmody. Reported-by: Phil Carmody <ext-phil.2.carmody@nokia.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Acked-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
2011-04-05UBIFS: unify error path dbg_debugfs_init_fsArtem Bityutskiy
This is just a small clean-up patch which simlifies and unifies the error path in the dbg_debugfs_init_fs(). We have common error path for all failure cases in this function except of the very first case. And this patch makes the first failure case use the same error path as the other cases by using the 'fname' and 'dent' variables. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Acked-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
2011-03-24UBIFS: use GFP_NOFS properlyArtem Bityutskiy
This patch fixes a brown-paperbag bug which was introduced by me: I used incorrect "GFP_KERNEL | GFP_NOFS" allocation flags to make sure my allocations do not cause write-back. But the correct form is "GFP_NOFS". Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-16UBIFS: save 128KiB or more RAMArtem Bityutskiy
When debugging is enabled, we allocate a buffer of PEB size for various debugging purposes. However, now all users of this buffer are gone and we can safely remove it and save 128KiB or more RAM. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-16UBIFS: allocate dump buffer on demandArtem Bityutskiy
Instead of using pre-allocated 'c->dbg->buf' buffer in 'dbg_dump_leb()', dynamically allocate it when needed. The intend is to get rid of the pre-allocated 'c->dbg->buf' buffer and save 128KiB of RAM (or more if PEB size is larger). Indeed, currently we allocate this memory even if the user never enables any self-check, which is wasteful. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-03-11UBIFS: simplify UBIFS Kconfig menuArtem Bityutskiy
Remove debug message level and debug checks Kconfig options as they proved to be useless anyway. We have sysfs interface which we can use for fine-grained debugging messages and checks selection, see Documentation/filesystems/ubifs.txt for mode details. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2011-02-06UBIFS: restrict world-writable debugfs filesVasiliy Kulikov
Don't allow everybody to dump sensitive information about filesystems. Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
2010-10-22Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds
* 'linux-next' of git://git.infradead.org/ubifs-2.6: UBIFS: do not allocate unneeded scan buffer UBIFS: do not forget to cancel timers UBIFS: remove a bit of unneeded code UBIFS: add a commentary about log recovery UBIFS: avoid kernel error if ubifs superblock read fails UBIFS: introduce new flags for RO mounts UBIFS: introduce new flag for RO due to errors UBIFS: check return code of pnode_lookup UBIFS: check return code of ubifs_lpt_lookup UBIFS: improve error reporting when reading bad node UBIFS: introduce list sorting debugging checks UBIFS: fix assertion warnings in comparison function UBIFS: mark unused key objects as invalid UBIFS: do not write rubbish into truncation scanning node UBIFS: improve assertion in node comparison functions UBIFS: do not use key type in list_sort UBIFS: do not look up truncation nodes UBIFS: fix assertion warning UBIFS: do not treat ENOSPC specially UBIFS: switch to RO mode after synchronizing