UBI volume notifications are intended to create the API to get clients
notified about volume creation/deletion, renaming and re-sizing. A
client can subscribe to these notifications using 'ubi_volume_register()'
and cancel the subscription using 'ubi_volume_unregister()'. When UBI
volumes change, a blocking notifier is called. Clients also can request
"added" events on all volumes that existed before client subscribed
to the notifications.

If we use notifications instead of calling functions like 'ubi_gluebi_xxx()',
we can make the MTD emulation layer to be more flexible: build it as a
separate module and load/unload it on demand.

[Artem: many cleanups, rework locking, add "updated" event, provide
 device/volume info in notifiers]
Signed-off-by: NDmitry Pervushin <dpervushin@embeddedalley.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch improves UBI errors handling. ATM UBI switches to
R/O mode when the WL worker fails to read the source PEB.
This means that the upper layers (e.g., UBIFS) has no
chances to unmap the erroneous PEB and fix the error.
This patch changes this behaviour and makes UBI put PEBs
like this into a separate RB-tree, thus preventing the
WL worker from hitting the same read errors again and
again.

But there is a 10% limit on a maximum amount of PEBs like this.
If there are too much of them, UBI switches to R/O mode.

Additionally, this patch teaches UBI not to panic and
switch to R/O mode if after a PEB has been copied, the
target LEB cannot be read back. Instead, now UBI cancels
the operation and schedules the target PEB for torturing.

The error paths has been tested by ingecting errors
into 'ubi_eba_copy_leb()'.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

This patch fixes the error path in the WL worker - in same cases
UBI oopses when 'goto out_error' happens and e1 or e2 are NULL.
This patch also cleans up the error paths a little. And I have
tested nearly all error paths in the WL worker.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>

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>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Extend erase timeout in M25P80 SPI Flash driver.

The M25P80 drivers fails erasing sectors on a M25P128 because the ready
wait timeout is too short. Change the timeout from a simple loop count to a
suitable number of seconds.
Signed-off-by: NPeter Horton <zero@colonel-panic.org>
Tested-by: NMartin Michlmayr <tbm@cyrius.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

There is a logic error in "whole chip erase" for the m25p80 family.  If
the whole device is successfully erased, erase_chip() will return 0, and
the code will fall through to the "else" clause, and do sector-by-sector
erase in addition to the whole-chip erase.  This patch corrects that.

Also, the MAX_READY_WAIT_COUNT is insufficient for an m25p16 connected
to a 400 MHz powerpc.  Increasing it allows me to successfully program
the device on my board.
Signed-off-by: NSteven A. Falco <sfalco@harris.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Wrong types on IRQ handler
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

MTD has got sysfs support in 2.6.30-rc1. But subpage size is not
exposed there - do this.

UBI utilities badly need this parameter. At the moment there is
no way to get subpage size - ioctls do not return it. And we
just got sysfs support, so we can easilly extend it with this
additional parameter.

This can be merged late in the development cycle because:
1. sysfs support has been just added - there are no users for
   it so far, even.
2. UBI utilities really need this parameter, and it is better
   not to delay this.
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

drivers/mtd/mtdcore.c: In function 'mtd_release':
drivers/mtd/mtdcore.c:51: warning: unused variable 'mtd'

[akpm: make it actually build]
Signed-off-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

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

Prevent NUMONYX M29W128G memories from using write buffer,
because it doesn't work properly.
Signed-off-by: NDarius Augulis <augulis.darius@gmail.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

In the existing implementation, ecc_stats fields are incremented only by
one, regardless of master mtd errors number. For example, if there are N
errors were corrected by ECC, partition ecc_stats.corrected will be
incremented by one.

This commit changes simple increment to sum of old value and parent mtd
error count.
Signed-off-by: NYauhen Kharuzhy <jekhor@gmail.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The NAND flash on the TQM8548_BE modules requires a short delay after
running the UPM pattern. The TQM8548_BE requires a further short delay
after writing out a buffer. Normally the R/B pin should be checked, but
it's not connected on the TQM8548_BE. The existing driver uses similar
fixed delay points. To manage these extra delays in a more general way,
I introduced the "fsl,ump-wait-flags" property allowing the board-
specific driver to specify various types of extra delay.
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Acked-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This patch adds support for multi-chip NAND devices to the FSL-UPM
driver. This requires support for multiple GPIOs for the RNB pins.
The NAND chips are selected through address lines defined by the
FDT property "fsl,upm-addr-line-cs-offsets".
Signed-off-by: NWolfgang Grandegger <wg@grandegger.com>
Acked-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NIlya Yanok <yanok@emcraft.com>
Acked-by: NWolfgang Grandegger <wg@grandegger.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NSebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Move the driver model init code out of the "#ifdef CONFIG_PROC_FS"
block.

Tested with both values of CONFIG_PROC_FS .  Tested with CONFIG_MTD=m .

Issue was reported here: http://lkml.org/lkml/2009/4/4/107Signed-off-by: NKevin Cernekee <kpc.mtd@gmail.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Follow-on patch to the previous driver model patch for the MTD
framework.  This one makes various MTD drivers connect to the
driver model tree, so /sys/devices/virtual/mtd/* nodes are no
longer present ... mostly drivers used on boards I have handy.

Based on a patch from Kay Sievers.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

1) Add more sysfs attributes: flags, size, erasesize, writesize,
   oobsize, numeraseregions, name

2) Move core_initcall() code into init_mtd().  The original approach
   does not work if CONFIG_MTD=m .

3) Add device_unregister() in del_mtd_device() so that devices get
   removed from sysfs as each driver is unloaded.
Signed-off-by: NKevin Cernekee <kpc.mtd@gmail.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Update driver model support in the MTD framework, so it fits
better into the current udev-based hotplug framework:

 - Each mtd_info now has a device node.  MTD drivers should set
   the dev.parent field to point to the physical device, before
   setting up partitions or otherwise declaring MTDs.

 - Those device nodes always map to /sys/class/mtdX device nodes,
   which no longer depend on MTD_CHARDEV.

 - Those mtdX sysfs nodes have a "starter set" of attributes;
   it's not yet sufficient to replace /proc/mtd.

 - Enabling MTD_CHARDEV provides /sys/class/mtdXro/ nodes and the
   /sys/class/mtd*/dev attributes (for udev, mdev, etc).

 - Include a MODULE_ALIAS_CHARDEV_MAJOR macro.  It'll work with
   udev creating the /dev/mtd* nodes, not just a static rootfs.

So the sysfs structure is pretty much what you'd expect, except
that readonly chardev nodes are a bit quirky.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

A pointer to plat_nand_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded.  Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.

An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Hamish Moffatt <hamish@cloud.net.au>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

A pointer to sa1100_mtd_probe is passed to the core via
platform_driver_register and so the function must not disappear when the
.init sections are discarded.  Otherwise (if also having HOTPLUG=y)
unbinding and binding a device to the driver via sysfs will result in an
oops as does a device being registered late.

An alternative to this patch is using platform_driver_probe instead of
platform_driver_register plus removing the pointer to the probe function
from the struct platform_driver.
Signed-off-by: NUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Nicolas Pitre <nico@marvell.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Reported-by: NDan Carpenter <error27@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMarcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The commit:

    platform driver: fix incorrect use of 'platform_bus_type' with 'struct device_driver'

contains this:

-static int __exit pxa2xx_flash_remove(struct device *dev)
+static int __exit pxa2xx_flash_remove(struct platform_device *dev)
...
-       .remove         = __exit_p(pxa2xx_flash_remove),
+       .remove         = __devexit_p(pxa2xx_flash_remove),

which leads to the following build error:

`pxa2xx_flash_remove' referenced in section `.data' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o

This is not the only instance of it in this patch - all __exit_p's
touched by this patch have been converted to __devexit_p's without
regard to the original function.

Let's revert this change and, if we are going to convert functions
to be __devexit/__devinit, lets have that as a _separate_ patch doing
just that change.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Impact: Replace and remove risky (non-EXPORTed) API

module_text_address() returns a pointer to the module, which given locking
improvements in module.c, is useless except to test for NULL:

1) If the module can't go away, use __module_text_address.
2) Otherwise, just use is_module_text_address().

Cc: linux-mtd@lists.infradead.org
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Fix this sparse warnings:
  drivers/mtd/tests/mtd_oobtest.c:139:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:192:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:219:41: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:284:25: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:525:25: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:545:25: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:569:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:589:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:613:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:633:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:673:41: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_oobtest.c:701:33: warning: Using plain integer as NULL pointer
  drivers/mtd/tests/mtd_readtest.c:74:41: warning: Using plain integer as NULL pointer
Signed-off-by: NHannes Eder <hannes@hanneseder.net>
Acked-by: NArtem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

There is no need to have a "\n" on a MODULE_DESCRIPTION, remove it.
Signed-off-by: NNiels de Vos <niels.devos@wincor-nixdorf.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>

simple_set_mnt() is defined as returning 'int' but always returns 0.
Callers assume simple_set_mnt() never fails and don't properly cleanup if
it were to _ever_ fail.  For instance, get_sb_single() and get_sb_nodev()
should:

        up_write(sb->s_unmount);
        deactivate_super(sb);

if simple_set_mnt() fails.

Since simple_set_mnt() never fails, would be cleaner if it did not
return anything.

[akpm@linux-foundation.org: fix build]
Signed-off-by: NSukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>