UBI: change the interface of a debugging check function

This is a minor preparational patch which changes the
'paranoid_check_in_wl_tree()' function interface by adding the 'ubi' parameter
which will be needed there in the next patch.

And while on it, add "const" qualifier to the 'ubi' parameter of the
'paranoid_check_in_pq()' function.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: use debugfs for the extra checks knobs

This patch introduces debugfs support to UBI. All the UBI stuff is kept in the
"ubi" debugfs directory, which contains per-UBI device "ubi/ubiX"
sub-directories, containing debugging files. This file also creates
"ubi/ubiX/chk_gen" and "ubi/ubiX/chk_io" knobs for switching general and I/O
extra checks on and off. And it removes the 'debug_chks' UBI module parameters.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: prepare debugging stuff to further debugfs conversion

We'll need the 'struct ubi_device *ubi' pointer in every debugging function (to
access the ->dbg field), so add this pointer to all the functions implementing
UBI debugging test modes like 'ubi_dbg_is_bitflip()' etc.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: make it possible to use struct ubi_device in debug.h

Current layout does not allow us to add inline functions to debug.h which use
the 'struct ubi_device' object, because it is undefined there. Move
'#include "debug.h"' in "ubi.h" down so to make 'struct ubi_device" be defined.
Additionally, this makes it possible to remove a bunch of forward declarations
in "debug.h". This is a preparation to the next patch.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: switch debugging tests knobs to debugfs

Kill the UBI 'debug_tsts' module parameter and switch to debugfs. Create
per-test mode files there. E.g., to enable bit-flips emulation you may just do:

echo 1 > /sys/kernel/debug/ubi/ubi0/tst_emulate_bitflips

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: fix oops in error path

This patch fixes an oops in the error path of 'ubi_attach_mtd_dev()'. If
anything after 'uif_init()' fails, we get an oops in 'cancel_pending()'. The
reason is that 'uif_close()' drops the last reference count for 'ubi->dev' and
whole 'struct ubi_device' is freed. And then
'ubi_wl_close()'->'cancel_pending()' tries to access the 'ubi' pointer and
problems begin.

Note, in 'ubi_detach_mtd_dev()' function we get a device reference to
work-around this issue. Do the same in the error path of
'ubi_attach_mtd_dev()'.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: dump stack when switching to R/O mode

If we have debugging enabled and switching to R/O mode because of an error -
dump the stack to improve UBI error reporting and make the further diagnostics
easier to do.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: remove dead code

Thanks to new gcc 4.6 for issuing the following warning:

drivers/mtd/ubi/vtbl.c: In function ‘create_vtbl’:
drivers/mtd/ubi/vtbl.c:311:33: warning: variable ‘old_seb’ set but not used [-Wunused-but-set-variable]

This patch removes some dead code and fixes the warning.

Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
UBI: clarify the volume notification types' doc

I realized the new descriptions of ADDED and REMOVED could also be
misleading: they can also be triggered after using a userland util
(ubi{mk,rm}vol).

Artem: amend the commentaries

Signed-off-by David Wagner <david.wagner@free-electrons.com>
Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>
hfsplus: assignments inside `if' condition clean-up

Make assignments outside `if' conditions for unicode.c module
where the checkpatch.pl script reported this coding style error.

Signed-off-by: Anton Salikhmetov <alexo@tuxera.com>
Signed-off-by: Christoph Hellwig <hch@tuxera.com>
hfsplus: fix overflow in hfsplus_get_block

For filesystems larger than 2TB the final sector number passed to
map_bh might overflow the range representable in a 32-bit data type.
Make sure we use a sector_t for it and the arithmetics calculating it.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>
hfsplus: fix overflow in hfsplus_read_wrapper

For partitions larger than 2TB or at such an offset the hfs wrapper code
in hfsplus might overflow the range representable in a 32-bit
data type. Make sure we use a sector_t for the arithmetics leading to it.

I'm not sure this code can be readed at all as hfs itself never supported
such large volumes.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>
hfsplus: lift the 2TB size limit

Replace the hardcoded 2TB limit with a dynamic limit based on the block
size now that we have fixed the few overflows preventing operation
with large volumes.

Signed-off-by: Christoph Hellwig <hch@tuxera.com>
dlm: show addresses in configfs

Display all addresses the dlm is using for the local node
from the configfs file config/dlm/<cluster>/comms/<comm>/addr_list
Also make the addr file write only.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
dlm: use vmalloc for hash tables

Allocate dlm hash tables in the vmalloc area to allow a greater
maximum size without restructuring of the hash table code.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
UBIFS: return EROFS in case of broken commit

If commit failed and it is in broken state, UBIFS switches to R/O mode. Most
operations return -EROFS in this case, except of commit which returns -EINVAL.
Make it return -EROFS too for consistency. This is also important for our power
cut emulation testing.

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: dump stack when pnode or nnode reading fails

When we fail to read a pnode or nnode - print stacktrace if debugging is enabled.

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: 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>