ubifs: ubifs_dump_sleb: Remove unused function

Function ubifs_dump_sleb() is defined but unused, it can be removed.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Limit dumping length by size of memory which is allocated for the node

To prevent memory out-of-bounds accessing in ubifs_dump_node(), actual
dumping length should be restricted by another condition(size of memory
which is allocated for the node).

This patch handles following situations (These situations may be caused
by bit flipping due to hardware error, writing bypass ubifs, unknown
bugs in ubifs, etc.):
1. bad node_len: Dumping data according to 'ch->len' which may exceed
the size of memory allocated for node.
2. bad node content: Some kinds of node can record additional data, eg.
index node and orphan node, make sure the size of additional data
not beyond the node length.
3. node_type changes: Read data according to type A, but expected type
B, before that, node is allocated according to type B's size. Length
of type A node is greater than type B node.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Cc: Richard Weinberger <richard@nod.at>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: linux-mtd@lists.infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612152120.GA17450@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 336

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details you should have received a copy of the gnu general
public license along with this program if not write to the free
software foundation inc 51 franklin st fifth floor boston ma 02110
1301 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 246 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.674189849@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ubifs: Rework ubifs_assert()

With having access to struct ubifs_info in ubifs_assert() we can
give more information when an assert is failing.
By using ubifs_err() we can tell which UBIFS instance failed.

Also multiple actions can be taken now.
We support:
- report: This is what UBIFS did so far, just report the failure and go
on.
- read-only: Switch to read-only mode.
- panic: shoot the kernel in the head.

Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Pass struct ubifs_info to ubifs_assert()

This allows us to have more context in ubifs_assert()
and take different actions depending on the configuration.

Signed-off-by: Richard Weinberger <richard@nod.at>

UBIFS: print less

UBIFS currently prints a lot of information when it mounts a volume, which
bothers some people. Make it less chatty - print only important information
by default.

Get rid of 'dbg_msg()' macro completely.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: use pr_ helper instead of printk

Use 'pr_err()' instead of 'printk(KERN_ERR', etc.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: print PID in debug messages

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: fix complaints about too small debug buffer size

When debugging is enabled, we use a temporary on-stack buffer for formatting
the key strings like "(11368871, direntry, 0xcd0750)". The buffer size is
32 bytes and sometimes it is not enough to fit the key string - e.g., when
inode numbers are high. This is not fatal, but the key strings are incomplete
and UBIFS complains like this:

UBIFS assert failed in dbg_snprintf_key at 137 (pid 1)

This is a regression caused by "515315a UBIFS: fix key printing".

Fix the issue by increasing the buffer to 48 bytes.

Reported-by: Michael Hench <michaelhench@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Tested-by: Michael Hench <michaelhench@gmail.com>
Cc: stable@vger.kernel.org [v3.3+]

UBIFS: add debugfs knob to switch to R/O mode

This patch adds another debugfs knob which switches UBIFS to R/O mode.
I needed it while trying to reproduce the 'first log node is not CS node'
bug. Without this debugfs knob you have to perform a power cut to repruduce
the bug. The knob is named 'ro_error' and all it does is it sets the
'ro_error' UBIFS flag which makes UBIFS disallow any further writes - even
write-back will fail with -EROFS. Useful for debugging.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

UBI: Kill data type hint

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>

UBIFS: get rid of dbg_err

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>

UBIFS: remove Kconfig debugging option

Have the debugging stuff always compiled-in instead. It simplifies maintanance
a lot.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: remove a couple of unused macros

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: rename dumping functions

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>

UBIFS: get rid of dbg_dump_stack

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>

UBIFS: make the dbg_lock spinlock static

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>

UBIFS: fix non-debug configuration build

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>

UBIFS: fix key printing

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: fix debugging messages

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 again

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+]

UBIFS: introduce a helper to dump scanning info

This commit adds 'dbg_dump_sleb()' helper function to dump scanning
information.

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>

UBIFS: not build debug messages with CONFIG_UBIFS_FS_DEBUG disabled

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>

UBIFS: rename recovery testing variables

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 superblocks

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 operations

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: introduce more I/O helpers

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: remove unused and unneeded debugging function

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 knobs

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: switch self-check knobs to debugfs

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 types

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 tests

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 prototype

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: rename dbg_check_dir_size function

Since this function is not only about size checking, rename it to
'dbg_check_dir()'.

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

UBIFS: improve inode dumping function

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>

UBIFS: lessen the size of debugging info data structure

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>

UBIFS: switch to dynamic printks

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>

UBIFS: fix kernel-doc comments

This is a minor fix for UBIFS kernel-doc comments - we forgot the "@" symbol
for several 'struct ubifs_debug_info'.

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

UBIFS: dump the stack on errors in failure mode too

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

UBIFS: make force in-the-gaps to be a general self-check

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>

UBIFS: improve space checking debugging feature

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>

UBIFS: fix compilation warnings when compiling with gcc 4.5

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: Maksim Rayskiy <maksim.rayskiy@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBIFS: clean-up commentaries

Clean-up commentaries in debug.h and remove references to non-existing
symblols.

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

UBIFS: save 128KiB or more RAM

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>

UBIFS: simplify UBIFS Kconfig menu

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>

UBIFS: introduce list sorting debugging checks

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

UBIFS: improve journal head debugging prints

Convert the journal head integer into the head name when printing
debugging information.

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

UBIFS: add inode size debugging check

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: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: Adrian Hunter <Adrian.Hunter@nokia.com>

UBIFS: add re-mount debugging checks

We observe space corrupted accounting when re-mounting. So add some
debbugging checks to catch problems like this.

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

UBIFS: introduce LPT dump function

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

UBIFS: add debugfs support

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

UBIFS: separate debugging fields out

Introduce a new data structure which contains all debugging
stuff inside. This is cleaner than having debugging stuff
directly in 'c'.

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

UBIFS: add more debugging messages for LPT

Also add debugging checks for LPT size and separate
out c->check_lpt_free from unrelated bitfields.

Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>

UBIFS: improve arguments checking in debugging messages

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

UBIFS: add new flash file system

This is a new flash file system. See
http://www.linux-mtd.infradead.org/doc/ubifs.html

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: Adrian Hunter <ext-adrian.hunter@nokia.com>