ubifs: Remove unreachable code in dbg_check_ltab_lnum

Because there is no break statement in the dead loop above,it is
impossible to execute the 'err=0' statement.Delete the code that
will never execute.

Fixes: 6fb324a4b0c3 ("UBIFS: allocate ltab checking buffer on demand")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Cc: Kunwu Chan <kunwu.chan@hotmail.com>
Suggested-by: Richard Weinberger <richard.weinberger@gmail.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

treewide: use get_random_u32_below() instead of deprecated function

This is a simple mechanical transformation done by:

@@
expression E;
@@
- prandom_u32_max
+ get_random_u32_below
(E)

Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Reviewed-by: SeongJae Park <sj@kernel.org> # for damon
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband
Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

treewide: use prandom_u32_max() when possible, part 1

Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:

@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)

@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@

- RAND = get_random_u32();
... when != RAND
- RAND %= (E);
+ RAND = prandom_u32_max(E);

// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@

((T)get_random_u32()@p & (LITERAL))

// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@

value = None
if literal.startswith('0x'):
value = int(literal, 16)
elif literal[0] in '123456789':
value = int(literal, 10)
if value is None:
print("I don't know how to handle %s" % (literal))
cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
print("Skipping 0x%x for cleanup elsewhere" % (value))
cocci.include_match(False)
elif value & (value + 1) != 0:
print("Skipping 0x%x because it's not a power of two minus one" % (value))
cocci.include_match(False)
elif literal.startswith('0x'):
coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))

// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@

- (FUNC()@p & (LITERAL))
+ prandom_u32_max(RESULT)

@collapse_ret@
type T;
identifier VAR;
expression E;
@@

{
- T VAR;
- VAR = (E);
- return VAR;
+ return E;
}

@drop_var@
type T;
identifier VAR;
@@

{
- T VAR;
... when != VAR
}

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

mm: remove the pgprot argument to __vmalloc

The pgprot argument to __vmalloc is always PAGE_KERNEL now, so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Michael Kelley <mikelley@microsoft.com> [hyperv]
Acked-by: Gao Xiang <xiang@kernel.org> [erofs]
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Wei Liu <wei.liu@kernel.org>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Link: http://lkml.kernel.org/r/20200414131348.444715-22-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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: authentication: Authenticate LPT

The LPT needs to be authenticated aswell. Since the LPT is only written
during commit it is enough to authenticate the whole LPT with a single
hash which is stored in the master node. Only the leaf nodes (pnodes)
are hashed which makes the implementation much simpler than it would be
to hash the complete LPT.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubifs: Export pnode_lookup as ubifs_pnode_lookup

ubifs_lpt_lookup could be implemented using pnode_lookup. To make that
possible move pnode_lookup from lpt.c to lpt_commit.c. Rename it to
ubifs_pnode_lookup since it's now exported.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
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: lpt: Fix wrong pnode number range in comment

The comment above pnode_lookup claims the range for the pnode number is
from 0 to main_lebs - 1. This is wrong because every pnode has
informations about UBIFS_LPT_FANOUT LEBs, thus the corrent range is
0 to to (main_lebs - 1) / UBIFS_LPT_FANOUT.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Weinberger <richard@nod.at>

UBIFS: improve function-level documentation

Fix various inconsistencies in the documentation associated with various
functions.

In the case of fs/ubifs/lprops.c, the second parameter of
ubifs_get_lp_stats was renamed from st to lst in commit 84abf972ccff
("UBIFS: add re-mount debugging checks")

In the case of fs/ubifs/lpt_commit.c, the excess variables have never
existed in the associated functions since the code was introduced into the
kernel.

The others appear to be straightforward typos.

Issues detected using Coccinelle (http://coccinelle.lip6.fr/)

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Richard Weinberger <richard@nod.at>

UBIFS: extend debug/message capabilities

In the case where we have more than one volumes on different UBI
devices, it may be not that easy to tell which volume prints the
messages. Add ubi number and volume id in ubifs_msg/warn/error
to help debug. These two values are passed by struct ubifs_info.

For those where ubifs_info is not initialized yet, ubifs_* is
replaced by pr_*. For those where ubifs_info is not avaliable,
ubifs_info is passed to the calling function as a const parameter.

The output looks like,

[ 95.444879] UBIFS (ubi0:1): background thread "ubifs_bgt0_1" started, PID 696
[ 95.484688] UBIFS (ubi0:1): UBIFS: mounted UBI device 0, volume 1, name "test1"
[ 95.484694] UBIFS (ubi0:1): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[ 95.484699] UBIFS (ubi0:1): FS size: 30220288 bytes (28 MiB, 238 LEBs), journal size 1523712 bytes (1 MiB, 12 LEBs)
[ 95.484703] UBIFS (ubi0:1): reserved for root: 1427378 bytes (1393 KiB)
[ 95.484709] UBIFS (ubi0:1): media format: w4/r0 (latest is w4/r0), UUID 40DFFC0E-70BE-4193-8905-F7D6DFE60B17, small LPT model
[ 95.489875] UBIFS (ubi1:0): background thread "ubifs_bgt1_0" started, PID 699
[ 95.529713] UBIFS (ubi1:0): UBIFS: mounted UBI device 1, volume 0, name "test2"
[ 95.529718] UBIFS (ubi1:0): LEB size: 126976 bytes (124 KiB), min./max. I/O unit sizes: 2048 bytes/2048 bytes
[ 95.529724] UBIFS (ubi1:0): FS size: 19808256 bytes (18 MiB, 156 LEBs), journal size 1015809 bytes (0 MiB, 8 LEBs)
[ 95.529727] UBIFS (ubi1:0): reserved for root: 935592 bytes (913 KiB)
[ 95.529733] UBIFS (ubi1:0): media format: w4/r0 (latest is w4/r0), UUID EEB7779D-F419-4CA9-811B-831CAC7233D4, small LPT model

[ 954.264767] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node type (255 but expected 6)
[ 954.367030] UBIFS error (ubi1:0 pid 756): ubifs_read_node: bad node at LEB 0:0, LEB mapping status 1

Signed-off-by: Sheng Yong <shengyong1@huawei.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

UBIFS: remove useless statements

This patch removes useless and duplicate statements.

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

UBIFS: fix error handling in dump_lpt_leb()

This patch checks the return value of 'ubifs_unpack_nnode()'.
If this function returns an error, 'nnode' may not be
initialized, so just print an error message and break.

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

arch: Mass conversion of smp_mb__*()

Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

UBIFS: rename random32() to prandom_u32()

Use more preferable function name which implies using a pseudo-random
number generator.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>

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: comply with coding style

Join all the split printk lines in order to stop checkpatch complaining.

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: 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: switch to ubifs_leb_read

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: 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: use correct flags in lprops

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: introduce lsave debugging

Try to improve UBIFS testing coverage by randomly picking LEBs to
store in lsave, rather than picking them optimally. Create a debugging
version of 'populate_lsave()' for these purposes and enable it when
general debugging self-checks are enabled.

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

UBIFS: fix minor stylistic issues

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>

UBIFS: use GFP_NOFS properly

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>

UBIFS: allocate lpt dump buffer on demand

Instead of using pre-allocated 'c->dbg->buf' buffer in
'dump_lpt_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>

UBIFS: allocate ltab checking buffer on demand

Instead of using pre-allocated 'c->dbg->buf' buffer in
'dbg_check_ltab_lnum()', 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>

UBIFS: check return code of pnode_lookup

Function pnode_lookup may return ERR_PTR(...). Check for it.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBIFS: use ERR_CAST

Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)). The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking 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>

UBIFS: fix commentaries

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

UBIFS: use KERN_CONT

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

UBIFS: fix lprops committing bug

When writing lprop nodes, do not forget to set @from to 0 when
switching the LEB. This fixes the following bug:

UBIFS error (pid 27768): ubifs_leb_write: writing -15456 bytes at 16:15880, error -22
UBIFS error (pid 27768): do_commit: commit failed, error -22
UBIFS warning (pid 27768): ubifs_ro_mode: switched to read-only mode, error -22
Pid: 27768, comm: freespace Not tainted 2.6.29-rc4-ubifs-2.6 #43
Call Trace:
[<ffffffffa00c46d6>] ubifs_ro_mode+0x54/0x56 [ubifs]
[<ffffffffa00cfa16>] do_commit+0x4f5/0x50a [ubifs]
[<ffffffffa00cfae7>] ubifs_run_commit+0xbc/0xdb [ubifs]
[<ffffffffa00d42b9>] ubifs_budget_space+0x742/0x9ed [ubifs]
[<ffffffff812daf45>] ? __mutex_lock_common+0x361/0x3ae
[<ffffffffa00bc437>] ? ubifs_write_begin+0x18d/0x44c [ubifs]
[<ffffffffa00bc5cb>] ubifs_write_begin+0x321/0x44c [ubifs]
[<ffffffff8106222b>] ? trace_hardirqs_on_caller+0x1f/0x14d
[<ffffffff81097ce2>] generic_file_buffered_write+0x12f/0x2d9
[<ffffffff8109828d>] __generic_file_aio_write_nolock+0x261/0x295
[<ffffffff81098aff>] generic_file_aio_write+0x69/0xc5
[<ffffffffa00bb914>] ubifs_aio_write+0x14c/0x19e [ubifs]
[<ffffffff810c8f42>] do_sync_write+0xe7/0x12d
[<ffffffff81055378>] ? autoremove_wake_function+0x0/0x38
[<ffffffff81149edc>] ? security_file_permission+0x11/0x13
[<ffffffff810c9827>] vfs_write+0xab/0x105
[<ffffffff810c9945>] sys_write+0x47/0x6f
[<ffffffff8100c35b>] system_call_fastpath+0x16/0x1b

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

UBIFS: fix dbg_chk_lpt_sz()

The debugging function dbg_chk_lpt_sz() was not working
correctly for small min_io_unit size e.g. NOR flash.

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

UBIFS: fix LPT out-of-space bug (again)

The function to traverse and dirty the LPT was still not
dirtying all nodes, with the result that the LPT could
run out of space.

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

UBIFS: fix numerous spelling mistakes

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

UBIFS: fix checkpatch.pl warnings

These are mostly long lines and wrong indentation warning
fixes. But also there are two volatile variables and
checkpatch.pl complains about them:

WARNING: Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt
+ volatile int gc_seq;

WARNING: Use of volatile is usually wrong: see Documentation/volatile-considered-harmful.txt
+ volatile int gced_lnum;

Well, we anyway use smp_wmb() for c->gc_seq and c->gced_lnum, so
these 'volatile' modifiers can be just dropped.

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

UBIFS: introduce LPT dump function

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

UBIFS: dump stack in LPT check functions

It is useful to know how we got to the checking function when
hunting the bugs.

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

UBIFS: run debugging checks only if they are enabled

Do not forget to check whether lpt debugging is enabled before
running the check functions. This commit also makes some spelling
fixes.

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: allow for gaps when dirtying the LPT

The LPT may have gaps in it because initially empty LEBs
are not added by mkfs.ubifs - because it does not know how
many there are. Then UBIFS allocates empty LEBs in the
reverse order that they are discovered i.e. they are
added to, and removed from, the front of a list. That
creates a gap in the middle of the LPT.

The function dirtying the LPT tree (for the purpose of
small model garbage collection) assumed that a gap could
only occur at the very end of the LPT and stopped dirtying
prematurely, which in turn resulted in the LPT running
out of space - something that is designed to be impossible.

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

UBIFS: check buffer length when scanning for LPT nodes

'is_a_node()' function was reading from a buffer before
checking the buffer length, resulting in an OOPS as
follows:

BUG: unable to handle kernel paging request at f8f74002
IP: [<f8f9783f>] :ubifs:ubifs_unpack_bits+0xca/0x233
*pde = 19e95067 *pte = 00000000
Oops: 0000 [#1] PREEMPT SMP
Modules linked in: ubifs ubi mtdchar bio2mtd mtd brd video output
[last unloaded: mtd]

Pid: 6414, comm: integck Not tainted (2.6.27-rc6ubifs34 #23)
EIP: 0060:[<f8f9783f>] EFLAGS: 00010246 CPU: 0
EIP is at ubifs_unpack_bits+0xca/0x233 [ubifs]
EAX: 00000000 EBX: f6090630 ECX: d9badcfc EDX: 00000000
ESI: 00000004 EDI: f8f74002 EBP: d9badcec ESP: d9badcc0
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process integck (pid: 6414, ti=d9bac000 task=f727dae0 task.ti=d9bac000)
Stack: 00000006 f7306240 00000002 00000000 d9badcfc d9badd00 0000001c 00000000
f6090630 f6090630 f8f74000 d9badd10 f8fa1cc9 00000000 f8f74002 00000000
f8f74002 f60fe128 f6090630 f8f74000 d9badd68 f8fa1e46 00000000 0001e000
Call Trace:
[<f8fa1cc9>] ? is_a_node+0x30/0x90 [ubifs]
[<f8fa1e46>] ? dbg_check_ltab+0x11d/0x5bd [ubifs]
[<f8fa388f>] ? ubifs_lpt_start_commit+0x42/0xed3 [ubifs]
[<c038e76a>] ? mutex_unlock+0x8/0xa
[<f8f9625d>] ? ubifs_tnc_start_commit+0x1c8/0xedb [ubifs]
[<f8f8d90b>] ? do_commit+0x187/0x523 [ubifs]
[<c038e76a>] ? mutex_unlock+0x8/0xa
[<f8f7ca17>] ? bud_wbuf_callback+0x22/0x28 [ubifs]
[<f8f8dd1d>] ? ubifs_run_commit+0x76/0xc0 [ubifs]
[<f8f8032c>] ? ubifs_sync_fs+0xd2/0xe6 [ubifs]
[<c01a2e97>] ? vfs_quota_sync+0x0/0x17e
[<c01a5ba6>] ? quota_sync_sb+0x26/0xbb
[<c01a2e97>] ? vfs_quota_sync+0x0/0x17e
[<c01a5c5d>] ? sync_dquots+0x22/0x12c
[<c0173d1b>] ? __fsync_super+0x19/0x68
[<c0173d75>] ? fsync_super+0xb/0x19
[<c0174065>] ? generic_shutdown_super+0x22/0xe7
[<c01a31fc>] ? vfs_quota_off+0x0/0x5fd
[<f8f7cf4d>] ? ubifs_kill_sb+0x31/0x35 [ubifs]
[<c01741f9>] ? deactivate_super+0x5e/0x71
[<c0187610>] ? mntput_no_expire+0x82/0xe4
[<c0187905>] ? sys_umount+0x4c/0x2f6
[<c0187bc8>] ? sys_oldumount+0x19/0x1b
[<c0103b71>] ? sysenter_do_call+0x12/0x25
=======================
Code: c1 f8 03 8d 04 07 8b 4d e8 89 01 8b 45 e4 89 10 89 d8 89 f1 d3 e8 85 c0
74 07 29 d6 83 fe 20 75 2a 89 d8 83 c4 20 5b 5e 5f 5d
EIP: [<f8f9783f>] ubifs_unpack_bits+0xca/0x233 [ubifs] SS:ESP 0068:d9badcc0
---[ end trace 1f02572436518c13 ]---

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