This patch is a clean-up and a preparation for the following
patches. It introduece constants for the return values of the
'ubi_eba_copy_leb()' function.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch fixes a minor problem where we may fail to wake
upe the UBI background thread. This is not fatal at all,
it may just result at sligtly worse performace for a short
period of time, just because the thread will be woken up
when real I/O on the UBI starts.

Anywey, the issue is the race condition between
'ubi_attach_mtd_dev()' and 'ubi_thread()'. If we do not
serialize them, the 'wake_up_process()' call may be done
before 'ubi_thread()' went seep, but after it checked
'ubi->thread_enabled'.

This issue was spotted by Shin Hong <hongshin@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The @vol->upd_marker should be protected by the @ubi->device_mutex,
otherwise 'paranoid_check_volume()' complains sometimes because
vol->upd_marker is 1 while vtbl_rec->upd_marker is 0.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

If a volume paranoid check fails, do not return an error
code to the caller, but just print error messages and go
forward. The primary reason for this is that it is difficult
to recover and cancel the operation at that stage.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

I am experiencing an error in 'paranoid_check_volume()'. Add
dump_stack() there to make it easier to identify the reasons
of the error.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

When paranoid checs are enabled, the 'io_paral' test from the
'mtd-utils' package fails. The symptoms are:

UBI error: paranoid_check_all_ff: flash region at PEB 3973:512, length 15872 does not contain all 0xFF bytes
UBI error: paranoid_check_all_ff: paranoid check failed for PEB 3973
UBI: hex dump of the 512-16384 region

It turned out to be a bug in the checking function. Suppose there
are 2 tasks - A and B. Task A is the wear-levelling working
('wear_leveling_worker()'). It is reading the VID header to find
which LEB this PEB belongs to. Say, task A is reading header
of PEB X. Suppose PEB X is unmapped, and has no VID header.
Task B is trying to write to PEB X.

Task A: in 'ubi_io_read_vid_hdr()': reads the VID header from PEB X.
        The read data contain all 0xFF bytes.
Task B: writes VID header and some data to PEB X
Task A: assumes PEB X is empty, calls 'paranoid_check_all_ff()', which
        fails.

The solution for this problem is to make 'paranoid_check_all_ff()'
re-read the VID header, re-check it, and only if it is not there,
check the rest. This now implemented by the 'paranoid_check_empty()'
function.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The @ubi->dbg_peb_buf is needed only when paranoid checks are
enabled, not when debugging in general is enabled.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Various minor improvements to the debugging messages which
I found useful while hunting problems.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The mutex essencially protects the entire UBI device, so the
old @volumes_mutex name is a little misleading.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The @mult_mutex does not serve any purpose. We already have
@volumes_mutex and it is enough. The @volume mutex is pushed
down to the 'ubi_rename_volumes()', because we want first
to open all volumes in the exclusive mode, and then lock the
mutex, just like all other ioctl's (remove, re-size, etc) do.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Now, we can call fsync() on an UBI volume.
Signed-off-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Introduce a new ioctl UBI_IOCSETPROP to set properties
on a volume. Also add the first property:
UBI_PROP_DIRECT_WRITE, this property is used to set the
ability to use direct writes in userspace
Signed-off-by: NSidney Amani <seed@uffs.org>
Signed-off-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

GregKH asked to fix UBI which has fake device release method. Indeed,
we have to free UBI device description object from the release method,
because otherwise we'll oops is someone opens a UBI device sysfs file,
then the device is removed, and he reads the file. With this fix, he
will get -ENODEV instead of an oops.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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

Get rid of 'do_div()' and use more user-friendly primitives from
'linux/math64.h'.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBI ioctl's do not work when running 64-bit kernel and 32-bit
user-land. Fix this by adding the compat_ioctl method.

Also, UBI serializes all ioctls, so more than one ioctl at a time
is not a problem. Amd UBI does not seem to depend on anything else,
so use unlocked_ioctl instead of ioctl (no BKL needed).
Reported-by: NGeert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Reviewed-by: NArnd Bergmann <arnd@arndb.de>

Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Some ioctl's in UBI are enabled only when debugging is switched
on. There is not particular reason for this, just noone needed
them. However, some people need the now for their user-space
development. Thus, allow these ioctl's even if UBI debugging
is disabled.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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

This patch adds ioctl to check if an LEB is mapped or not (as a
debugging option so far).

[Re-named ioctl to make it look the same as the other one and made
 some minor stylistic changes. Artem Bityutskiy.]
Signed-off-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch adds ioctl for the LEB unmap operation (as a debugging
option so far).

[Re-named ioctl to make it look the same as the other one and made
 some minor stylistic changes. Artem Bityutskiy.]
Signed-off-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch adds ioctl for the LEB map operation (as a debugging
option so far).

[Re-named ioctl to make it look the same as the other one and made
 some minor stylistic changes. Artem Bityutskiy.]
Signed-off-by: NCorentin Chary <corentincj@iksaif.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

When I review ocfs2 code, find there are 2 typos to "successfull".  After
doing grep "successfull " in kernel tree, 22 typos found totally -- great
minds always think alike :)

This patch fixes all the similar typos. Thanks for Randy's ack and comments.
Signed-off-by: NColy Li <coyli@suse.de>
Acked-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NRoland Dreier <rolandd@cisco.com>
Cc: Jeremy Kerr <jk@ozlabs.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Vlad Yasevich <vladislav.yasevich@hp.com>
Cc: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

CC: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

- (better, more, bigger ...) then -> (...) than
Signed-off-by: NFrederik Schwarzer <schwarzerf@gmail.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

Just minor indentation and "over 80 characters" fixes.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

UBI has 2 RB-trees to implement PEB protection, which is too
much for simply prevent PEB from being moved for some time.
This patch implements this using lists. The benefits:

1. No need to allocate protection entry on each PEB get.
2. No need to maintain balanced trees and walk them.
Signed-off-by: NXiaochuan-Xu <xiaochuan-xu@cqu.edu.cn>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch modifies @struct ubi_wl_entry and adds union which
contains only one element so far. This is just a preparation
for further changes which will kill the protection tree and
make UBI use a list instead.
Signed-off-by: NXiaochuan-Xu <xiaochuan-xu@cqu.edu.cn>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

MTD internal API presently uses 32-bit values to represent
device size.  This patch updates them to 64-bits but leaves
the external API unchanged.  Extending the external API
is a separate issue for several reasons.  First, no one
needs it at the moment.  Secondly, whether the implementation
is done with IOCTLs, sysfs or both is still debated.  Thirdly
external API changes require the internal API to be accepted
first.

Note that although the MTD API will be able to support 64-bit
device sizes, existing drivers do not and are not required
to do so, although NAND base has been updated.

In general, changing from 32-bit to 64-bit values cause little
or no changes to the majority of the code with the following
exceptions:
    	- printk message formats
    	- division and modulus of 64-bit values
    	- NAND base support
	- 32-bit local variables used by mtdpart and mtdconcat
	- naughtily assuming one structure maps to another
	in MEMERASE ioctl
Signed-off-by: NAdrian Hunter <ext-adrian.hunter@nokia.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Return with correct error code (-ENOMEM) from ubi_attach_mtd_dev() upon
failing vmalloc().
Signed-off-by: NStefan Roese <sr@denx.de>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

When a PEB is moved and a write error happens, UBI switches
to R/O mode, which is wrong, because we just copy the data
and may select a different PEB and re-try this. This patch
fixes WL worker's behavior.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Make sure the resources had not already been freed before
freeing them in the error path of the WL worker function.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

Minor code re-structuring and commentaries fixes to improve readability.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

We cannot call 'ubi_wl_get_peb()' with @ubi->buf_mutex locked,
because 'ubi_wl_get_peb()' may force erasure, which, in turn,
may call 'torture_peb()' which also locks the @ubi->buf_mutex
and deadlocks.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

The 'ubi_io_read_vid_hdr()' and 'ubi_io_read_ec_hdr()' function
have the 'verbose' argument which controls whether they should
print a warning if the VID/EC header was not found or was corrupted.
Some callers require the headers to be OK, and pass 1. Some allow
a corrupted/not present header, and pass 0.

       if (UBI_IO_DEBUG)
               verbose = 1;

And UBI_IO_DEBUG is 1 if CONFIG_MTD_UBI_DEBUG_MSG_BLD is true. So in
this case the warning is printed all the time. This confuses people.

Thus, do not print the messages as warnings if UBI_IO_DEBUG is true,
but print them as debugging messages instead.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

If ubi_thread() exits but kthread_should_stop() is not true
then kthread_stop() will never return and cleanup thread
will forever stay in "D" state.
Signed-off-by: NVitaliy Gusev <vgusev@openvz.org>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

'ubi_io_read_data()' may return EBADMSG in case of an ECC error,
and we should not panic because of this. We have CRC32 checksum
and may check the data. So just ignore the EBADMSG error.

This patch also fixes a minor spelling error at the same time.
Signed-off-by: NZoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch makes debugging a missconfigured UBI a bit easier
by providing the needed information in the boot log.
Signed-off-by: NDeepak Saxena <dsaxena@laptop.org>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

In case of error, the function add_volume returns an ERR pointer. The
result of IS_ERR, which is supposed to be used in a test as it is, is
here checked to be less than zero, which seems odd. We suggest to
replace this test by a simple IS_ERR test.

A simplified version of the semantic match that finds this problem is
as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@def0@
expression x;
position p0;
@@
x@p0 = add_volume(...)

@protected@
expression def0.x,E;
position def0.p0;
position p;
statement S;
@@
x@p0
... when != x = E
if (!IS_ERR(x) && ...) {<... x@p ...>} else S

@unprotected@
expression def0.x,E;
identifier fld;
position def0.p0;
position p != protected.p;
@@
x@p0
... when != x = E
* x@p->fld
// </smpl>
Signed-off-by: NJulien Brunel <brunel@diku.dk>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>