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* UBIFS: fix non-debug configuration buildDominique Martinet2012-01-15
| | | | | | | | | | Fix a brown paperbag bug introduced by me in the previous commit. I was in hurry and forgot about the non-debug case completely. Artem: amend the commit message and tweak the patch to preserve alignment. This made the patch a bit less readable, though. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
* Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds2012-01-13
|\ | | | | | | | | | | | | | | | | | | * 'linux-next' of git://git.infradead.org/ubifs-2.6: UBIFS: fix key printing UBIFS: use snprintf instead of sprintf when printing keys UBIFS: fix debugging messages UBIFS: make debugging messages light again UBI: fix debugging messages UBI: make vid_hdr non-static
| * UBIFS: fix key printingArtem Bityutskiy2012-01-13
| | | | | | | | | | | | | | | | | | | | | | | | 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>
| * UBIFS: use snprintf instead of sprintf when printing keysArtem Bityutskiy2012-01-13
| | | | | | | | | | | | | | 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>
| * UBIFS: fix debugging messagesArtem Bityutskiy2012-01-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Patch 56e46742e846e4de167dde0e1e1071ace1c882a5 broke UBIFS debugging messages: before that commit when UBIFS debugging was enabled, users saw few useful debugging messages after mount. However, that patch turned 'dbg_msg()' into 'pr_debug()', so to enable the debugging messages users have to enable them first via /sys/kernel/debug/dynamic_debug/control, which is very impractical. This commit makes 'dbg_msg()' to use 'printk()' instead of 'pr_debug()', just as it was before the breakage. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: stable@kernel.org [3.0+]
| * UBIFS: make debugging messages light againArtem Bityutskiy2012-01-11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We switch to dynamic debugging in commit 56e46742e846e4de167dde0e1e1071ace1c882a5 but did not take into account that now we do not control anymore whether a specific message is enabled or not. So now we lock the "dbg_lock" and release it in every debugging macro, which make them not so light-weight. This commit removes the "dbg_lock" protection from the debugging macros to fix the issue. The downside is that now our DBGKEY() stuff is broken, but this is not critical at all and will be fixed later. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Cc: stable@kernel.org [3.0+]
* | Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds2012-01-10
|\ \ | | | | | | | | | | | | | | | | | | * 'linux-next' of git://git.infradead.org/ubifs-2.6: UBI: fix use-after-free on error path UBI: fix missing scrub when there is a bit-flip UBIFS: Use kmemdup rather than duplicating its implementation
| * | UBIFS: Use kmemdup rather than duplicating its implementationThomas Meyer2011-11-22
| | | | | | | | | | | | | | | | | | | | | | | | The semantic patch that makes this change is available in scripts/coccinelle/api/memdup.cocci. Signed-off-by: Thomas Meyer <thomas@m3y3r.de> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
* | | vfs: switch ->show_options() to struct dentry *Al Viro2012-01-06
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | ubifs: propagate umode_tAl Viro2012-01-03
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | switch ->mknod() to umode_tAl Viro2012-01-03
| | | | | | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | switch ->create() to umode_tAl Viro2012-01-03
| | | | | | | | | | | | | | | | | | | | | | | | vfs_create() ignores everything outside of 16bit subset of its mode argument; switching it to umode_t is obviously equivalent and it's the only caller of the method Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | switch vfs_mkdir() and ->mkdir() to umode_tAl Viro2012-01-03
| | | | | | | | | | | | | | | | | | | | | vfs_mkdir() gets int, but immediately drops everything that might not fit into umode_t and that's the only caller of ->mkdir()... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | vfs: fix the stupidity with i_dentry in inode destructorsAl Viro2012-01-03
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Seeing that just about every destructor got that INIT_LIST_HEAD() copied into it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once(); the cost of taking it into inode_init_always() will be negligible for pipes and sockets and negative for everything else. Not to mention the removal of boilerplate code from ->destroy_inode() instances... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | vfs: mnt_drop_write_file()Al Viro2012-01-03
| | | | | | | | | | | | | | | | | | | | | new helper (wrapper around mnt_drop_write()) to be used in pair with mnt_want_write_file(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | switch a bunch of places to mnt_want_write_file()Al Viro2012-01-03
| |/ |/| | | | | | | | | it's both faster (in case when file has been opened for write) and cleaner. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | ubifs: too early register_filesystem()Al Viro2011-12-13
|/ | | | | | doing that before you are ready to handle mount() is a Bad Idea(tm)... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6Linus Torvalds2011-11-07
|\ | | | | | | | | | | * 'linux-next' of git://git.infradead.org/ubifs-2.6: UBIFS: fix the dark space calculation UBIFS: introduce a helper to dump scanning info
| * UBIFS: fix the dark space calculationsrimugunthan dhandapani2011-08-26
| | | | | | | | | | | | | | | | | | The dark space calculation should be 64 bit type-casted, when assigning to tmp64 (similar to how total_free is calculated). Overflow will occur for very large flashes. Signed-off-by: srimugunthan <srimugunthan.dhandapani@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
| * UBIFS: introduce a helper to dump scanning infoArtem Bityutskiy2011-08-22
| | | | | | | | | | | | | | This commit adds 'dbg_dump_sleb()' helper function to dump scanning information. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
* | Merge branch 'writeback-for-linus' of ↵Linus Torvalds2011-11-06
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux * 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Add a 'reason' to wb_writeback_work writeback: send work item to queue_io, move_expired_inodes writeback: trace event balance_dirty_pages writeback: trace event bdi_dirty_ratelimit writeback: fix ppc compile warnings on do_div(long long, unsigned long) writeback: per-bdi background threshold writeback: dirty position control - bdi reserve area writeback: control dirty pause time writeback: limit max dirty pause time writeback: IO-less balance_dirty_pages() writeback: per task dirty rate limit writeback: stabilize bdi->dirty_ratelimit writeback: dirty rate control writeback: add bg_threshold parameter to __bdi_update_bandwidth() writeback: dirty position control writeback: account per-bdi accumulated dirtied pages
| * | writeback: Add a 'reason' to wb_writeback_workCurt Wohlgemuth2011-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This creates a new 'reason' field in a wb_writeback_work structure, which unambiguously identifies who initiates writeback activity. A 'wb_reason' enumeration has been added to writeback.h, to enumerate the possible reasons. The 'writeback_work_class' and tracepoint event class and 'writeback_queue_io' tracepoints are updated to include the symbolic 'reason' in all trace events. And the 'writeback_inodes_sbXXX' family of routines has had a wb_stats parameter added to them, so callers can specify why writeback is being started. Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Curt Wohlgemuth <curtw@google.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
* | | filesystems: add set_nlink()Miklos Szeredi2011-11-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | Replace remaining direct i_nlink updates with a new set_nlink() updater function. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
* | | filesystems: add missing nlink wrappersMiklos Szeredi2011-11-02
|/ / | | | | | | | | | | | | Replace direct i_nlink updates with the respective updater function (inc_nlink, drop_nlink, clear_nlink, inode_dec_link_count). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
* / UBIFS: not build debug messages with CONFIG_UBIFS_FS_DEBUG disabledMichal Marek2011-08-19
|/ | | | | | | | | | | | | | | | | | With $ grep -e UBIFS_FS_DEBUG -e DYNAMIC_DEBUG .config # CONFIG_UBIFS_FS_DEBUG is not set CONFIG_DYNAMIC_DEBUG=y Debug messages are kept in the object files due to the dynamic_pr_debug() macro, even if they are never going to be printed: $ make fs/ubifs/super.o $ strings fs/ubifs/super.o | grep 'compiled on' compiled on: Aug 11 2011 at 12:21:38 Use plain printk to fix this. Signed-off-by: Michal Marek <mmarek@suse.cz> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2011-07-22
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (107 commits) vfs: use ERR_CAST for err-ptr tossing in lookup_instantiate_filp isofs: Remove global fs lock jffs2: fix IN_DELETE_SELF on overwriting rename() killing a directory fix IN_DELETE_SELF on overwriting rename() on ramfs et.al. mm/truncate.c: fix build for CONFIG_BLOCK not enabled fs:update the NOTE of the file_operations structure Remove dead code in dget_parent() AFS: Fix silly characters in a comment switch d_add_ci() to d_splice_alias() in "found negative" case as well simplify gfs2_lookup() jfs_lookup(): don't bother with . or .. get rid of useless dget_parent() in btrfs rename() and link() get rid of useless dget_parent() in fs/btrfs/ioctl.c fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers drivers: fix up various ->llseek() implementations fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek Ext4: handle SEEK_HOLE/SEEK_DATA generically Btrfs: implement our own ->llseek fs: add SEEK_HOLE and SEEK_DATA flags reiserfs: make reiserfs default to barrier=flush ... Fix up trivial conflicts in fs/xfs/linux-2.6/xfs_super.c due to the new shrinker callout for the inode cache, that clashed with the xfs code to start the periodic workers later.
| * fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlersJosef Bacik2011-07-20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Btrfs needs to be able to control how filemap_write_and_wait_range() is called in fsync to make it less of a painful operation, so push down taking i_mutex and the calling of filemap_write_and_wait() down into the ->fsync() handlers. Some file systems can drop taking the i_mutex altogether it seems, like ext3 and ocfs2. For correctness sake I just pushed everything down in all cases to make sure that we keep the current behavior the same for everybody, and then each individual fs maintainer can make up their mind about what to do from there. Thanks, Acked-by: Jan Kara <jack@suse.cz> Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | UBIFS: fix master node recoveryAnatolij Gustschin2011-07-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When the 1st LEB was unmapped and written but 2nd LEB not, the master node recovery doesn't succeed after power cut. We see following error when mounting UBIFS partition on NOR flash: UBIFS error (pid 1137): ubifs_recover_master_node: failed to recover master node Correct 2nd master node offset check is needed to fix the problem. If the 2nd master node is at the end in the 2nd LEB, first master node is used for recovery. When checking for this condition we should check whether the master node is exactly at the end of the LEB (without remaining empty space) or whether it is followed by an empty space less than the master node size. Artem: when the error happened, offs2 = 261120, sz = 512, c->leb_size = 262016. Signed-off-by: Anatolij Gustschin <agust@denx.de> Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>
* | UBIFS: improve power cut emulation testingArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | UBIFS: rename recovery testing variablesArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | 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>
* | UBIFS: remove custom list of superblocksArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | 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>
* | UBIFS: stop re-defining UBI operationsArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | 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>
* | UBIFS: switch to I/O helpersArtem Bityutskiy2011-07-04
| | | | | | | | | | | | Switch the rest of direct UBI calls to UBIFS helper functions. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: switch to ubifs_leb_writeArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | Stop using 'ubi_leb_write()' directly and switch to the 'ubifs_leb_write()' helper. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: switch to ubifs_leb_readArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | Instead of using 'ubi_read()' function directly, used the 'ubifs_leb_read()' helper function instead. This allows to get rid of several redundant error messages and make sure that we always have a stack dump on read errors. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: introduce more I/O helpersArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Introduce the following I/O helper functions: 'ubifs_leb_read()', 'ubifs_leb_write()', 'ubifs_leb_change()', 'ubifs_leb_unmap()', 'ubifs_leb_map()', 'ubifs_is_mapped(). The idea is to wrap all UBI I/O functions in order to encapsulate various assertions and error path handling (error message, stack dump, switching to R/O mode). And there are some other benefits of this which will be used in the following patches. This patch does not switch whole UBIFS to use these functions yet. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: always print stacktrace when switching to R/O modeArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | When switching to R/O mode due to an I/O error, always dump the stack, not only when debugging is enabled. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: remove unused and unneeded debugging functionArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | UBIFS: add global debugfs knobsArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | 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>
* | UBIFS: introduce debugfs helpersArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | 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>
* | UBIFS: re-arrange debugging code a bitArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | UBIFS: be more informative in failure modeArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | 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>
* | UBIFS: switch self-check knobs to debugfsArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | UBIFS: lessen amount of debugging check typesArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | 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>
* | UBIFS: introduce helper functions for debugging checks and testsArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | UBIFS: amend debugging inode size check function prototypeArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | 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>
* | UBIFS: amend debugging name check function prototypeArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | Add 'struct ubifs_info *c' parameter to the 'dbg_check_name()' debugging function - it will be needed in one of the following commits where we switch to debugfs. So this is just a preparation. Mark parameters as 'const' while on it. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: add few commentaries about TNCArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | Add a couple of comments - while looking into TNC I could not easily figure out few facts, so it is a good idea to document them in the code. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: use correct flags in lpropsArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | | | The UBIFS lpt tree is in many aspects similar to the TNC tree, and we have similar flags for these trees. And by mistake we use the COW_ZNODE flag for LPT in some places, instead of the right flag COW_CNODE. And this works only because these two constants have the same value. This patch makes all the LPT code to use COW_CNODE and also changes COW_CNODE constant value to make sure we do not misuse the flags any more. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
* | UBIFS: harmonize znode flag helpersArtem Bityutskiy2011-07-04
| | | | | | | | | | | | | | | | | | | | | | We have 3 znode flags: cow, obsolete, dirty. For the last flag we have a 'ubifs_zn_dirty()' helper function, but for the other 2 flags we use 'test_bit()' directly. This patch makes the situation more consistent and introduces helpers for the other 2 flags: 'ubifs_zn_cow()' and 'ubifs_zn_obsolete()'. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>