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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

Remove the usage of the 'dbg_lock' spinlock from 'dbg_err()' and make
it static.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Before commit 56e46742 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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

Patch 56e46742 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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [3.0+]

We switch to dynamic debugging in commit
56e46742 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: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [3.0+]

This commit adds 'dbg_dump_sleb()' helper function to dump scanning
information.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NMichal Marek <mmarek@suse.cz>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@intel.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Since this function is not only about size checking, rename it to
'dbg_check_dir()'.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This is a minor fix for UBIFS kernel-doc comments - we forgot the "@" symbol
for several 'struct ubifs_debug_info'.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

When UBIFS is in the failure mode (used for power cut emulation testing) we for
some reasons do not dump the stack in many places, e.g., in assertions.
Probably at early days we had too many of them and disabled this to make the
development easier, but then never enabled. Nowadays I sometimes observe
assertion failures during power cut testing, but the useful stackdump is not
printed, which is bad. This patch makes UBIFS always print the stackdump when
debugging is enabled.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

When compiling UBIFS with CONFIG_UBIFS_FS_DEBUG not set,
gcc-4.5.2 generates a slew of "warning: statement with no effect"
on references to non-void functions defined as 0.
To avoid these warnings, replace #defines with dummy inline functions.

Artem: massage the patch a bit, also remove the duplicate
       'dbg_check_lprops()' prototype.
Signed-off-by: NMaksim Rayskiy <maksim.rayskiy@gmail.com>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Clean-up commentaries in debug.h and remove references to non-existing
symblols.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The UBIFS bug in the GC list sorting comparison functions inspired
me to write internal debugging check functions which verify that
the list of nodes is sorted properly.

So, this patch implements 2 new debugging functions:
 o 'dbg_check_data_nodes_order()' - check order of data nodes list
 o 'dbg_check_nondata_nodes_order()' - check order of non-data nodes list

The debugging functions are executed only if general UBIFS debugging checks are
enabled. And they are compiled out if UBIFS debugging is disabled.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Convert the journal head integer into the head name when printing
debugging information.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Add one more check to UBIFS - a check that makes sure that there
are no data nodes beyond inode size. And few commantaries fixes
along the line.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: NAdrian Hunter <Adrian.Hunter@nokia.com>

We observe space corrupted accounting when re-mounting. So add some
debbugging checks to catch problems like this.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

We need to have a possibility to see various UBIFS variables
and ask UBIFS to dump various information. Debugfs is what
we need.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Introduce a new data structure which contains all debugging
stuff inside. This is cleaner than having debugging stuff
directly in 'c'.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Also add debugging checks for LPT size and separate
out c->check_lpt_free from unrelated bitfields.
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>

Use "if (0) printk()" construct in debugging print macros to
make the debugging messages be checked even if debugging is
off.

This patch also removes some unneeded spaces and blank lines.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.htmlSigned-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>