On NAND flash devices, UBI reserves some physical erase blocks (PEB) for
bad block handling. Today, the number of reserved PEB can only be set as a
percentage of the total number of PEB in each MTD partition. For example, for a
NAND flash with 128KiB PEB, 2 MTD partition of 20MiB (mtd0) and 100MiB (mtd1)
and 2% reserved PEB:
 - the UBI device on mtd0 will have 2 PEB reserved
 - the UBI device on mtd1 will have 16 PEB reserved

The problem with this behaviour is that NAND flash manufacturers give a
minimum number of valid block (NVB) during the endurance life of the
device, e.g.:

Parameter             Symbol    Min    Max    Unit      Notes
--------------------------------------------------------------
Valid block number     NVB     1004    1024   Blocks     1

From this number we can deduce the maximum number of bad PEB that a device will
contain during its endurance life: a 128MiB NAND flash (1024 PEB) will not have
less than 20 bad blocks during the flash endurance life.

But the manufacturer doesn't tell where those bad block will appear. He doesn't
say either if they will be equally disposed on the whole device (and I'm pretty
sure they won't). So, according to the datasheets, we should reserve the
maximum number of bad PEB for each UBI device (worst case scenario: 20 bad
blocks appears on the smallest MTD partition).

So this patch make UBI use the whole MTD device size to calculate the maximum
bad expected eraseblocks.

The Kconfig option is in per1024 blocks, thus it can have a default value of 20
which is *very* common for NAND devices.
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

'mtd_get_device_size()' returns the size of the whole MTD device, that is the
mtd_info master size. This will be used by UBI to calculate the maximum number
of bad blocks (MBB) on a MTD device.

Artem: amended the patch a bit.
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

'struct mtd_info' is not modified by 'mtd_is_partition()' so it can be marked
as "const".
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

CONFIG_MTD_UBI_BEB_RESERVE and MIN_RESEVED_PEBS are no longer used,
since the amount of reserved eraseblocks for bad PEB handling is now
derived from 'ubi->bad_peb_limit' (ubi's maximum expected bad
eraseblocks).
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

The existing mechanism of reserving PEBs for bad PEB handling has two
flaws:
- It is calculated as a percentage of good PEBs instead of total PEBs.
- There's no limit on the amount of PEBs UBI reserves for future bad
  eraseblock handling.

This patch changes the mechanism to overcome these flaws.

The desired level of PEBs reserved for bad PEB handling (beb_rsvd_level)
is set to the maximum expected bad eraseblocks (bad_peb_limit) minus the
existing number of bad eraseblocks (bad_peb_count).

The actual amount of PEBs reserved for bad PEB handling is usually set
to the desired level (but in some circumstances may be lower than the
desired level, e.g. when attaching to a device that has too few
available PEBs to satisfy the desired level).

In the case where the device has too many bad PEBs (above the expected
limit), then the desired level, and the actual amount of PEBs reserved
are set to zero. No PEBs will be set aside for future bad eraseblock
handling - even if some PEBs are made available (e.g. by shrinking a
volume).
If another PEB goes bad, and there are available PEBs, then the
eraseblock will be marked bad (consuming one available PEB). But if
there are no available PEBs, ubi will go into readonly mode.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>

Introduce 'ubi->bad_peb_limit', which specifies an upper limit of PEBs
UBI expects to go bad.  Currently, it is initialized to a fixed percentage
of total PEBs in the UBI device (configurable via CONFIG_MTD_UBI_BEB_LIMIT).

The 'bad_peb_limit' is intended to be used for calculating the amount of PEBs
UBI needs to reserve for bad eraseblock handling.

Artem: minor amendments.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

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

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

The newly added dmaengine support in the omap2 nand driver
potentially causes an undefined return value from the
omap_nand_probe function when dmaengine_slave_config
reports an error. Let's handle this by returning the
same error back to the caller.

Without this patch, building omap2plus_defconfig results in:

drivers/mtd/nand/omap2.c: In function 'omap_nand_probe':
drivers/mtd/nand/omap2.c:1154:6: warning: 'err' may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Grazvydas Ignotas <notasas@gmail.com>

It is not currently possible to build the gpmi-nand driver without
also building the mxs-dma driver. Clarify this Kconfig and enable
both in the defconfig file so we can build it again with both enabled.

drivers/built-in.o: In function `gpmi_dma_filter':
clk-fixed-factor.c:(.text+0xafc18): undefined reference to `mxs_dma_is_apbh'
make[1]: *** [vmlinux] Error 1
make: *** [sub-make] Error 2
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Acked-by: NDirk Behme <dirk.behme@de.bosch.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <kernel@pengutronix.de>

Remove the private DMA API implementation from nand/omap2.c
making it use entirely the DMA engine API.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add DMA engine support to the OMAP2 NAND driver.  This supplements the
private DMA API implementation contained within this driver, and the
driver can be independently switched at build time between using DMA
engine and the private DMA API.
Tested-by: NGrazvydas Ignotas <notasas@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

It has been decided to use marvell, not mrvl, in the compatibility
property. Search & replace.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>

The clk patches added code to get and enable clocks in the
respective driver probe functions.  If the probe function failed
for some reason after enabling the clock, the clock was not
disabled again in many cases.
Signed-off-by: NSimon Baatz <gmbnomis@gmail.com>
Signed-off-by: NAndrew Lumm <andrew@lunn.ch>

The platform data can now specify which external memory banks to probe
for NAND chips, and in which order. Banks that contain a NAND are used
and the other banks are freed.

Squashed version of development done in jz-2.6.38 branch.
Original patch by Lars-Peter Clausen with some bug fixes from me.
Thanks to Paul Cercueil for the initial autodetection patch.
Signed-off-by: NMaarten ter Huurne <maarten@treewalker.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3560/Acked-By: NDavid Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Currently, there are several locations where an attempt to reserve more
PEBs for bad PEB handling is made, with the same code being duplicated.

Harmonize it by introducing 'ubi_update_reserved()'.

Also, improve the debug message issued, making it more descriptive.

Artem: amended the patch a little.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

The function name within the comment was not aligned with the actual
function name.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

Signed-off-by: NPeter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: NArtem Bityutskiy <Artem.Bityutskiy@linux.intel.com>

The actual value (1%) is too low for actual NAND devices, a huge
majority of device has 2% maximum bad blocks (SLC or MLC).
(Actually it's 20 blocks on a 1024 blocks device, 40/2048...)
Signed-off-by: NRichard Genoud <richard.genoud@gmail.com>

Pass mount flags to sget() so that it can use them in initialising a new
superblock before the set function is called.  They could also be passed to the
compare function.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

We don't need to open code the divide function, just use div_u64 that
already exists and do the same job. While this is a straightforward
clean up, there is more to that, the real motivation for this.

While building on a cross compiling environment in armel, using gcc
4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5), I was getting the following build
error:

ERROR: "__aeabi_uldivmod" [drivers/mtd/nand/nandsim.ko] undefined!

After investigating with objdump and hand built assembly version
generated with the compiler, I narrowed __aeabi_uldivmod as being
generated from the divide function. When nandsim.c is built with
-fno-inline-functions-called-once, that happens when
CONFIG_DEBUG_SECTION_MISMATCH is enabled, the do_div optimization in
arch/arm/include/asm/div64.h doesn't work as expected with the open
coded divide function: even if the do_div we are using doesn't have a
constant divisor, the compiler still includes the else parts of the
optimized do_div macro, and translates the divisions there to use
__aeabi_uldivmod, instead of only calling __do_div_asm -> __do_div64 and
optimizing/removing everything else out.

So to reproduce, gcc 4.6 plus CONFIG_DEBUG_SECTION_MISMATCH=y and
CONFIG_MTD_NAND_NANDSIM=m should do it, building on armel.

After this change, the compiler does the intended thing even with
-fno-inline-functions-called-once, and optimizes out as expected the
constant handling in the optimized do_div on arm. As this also avoids a
build issue, I'm marking for Stable, as I think is applicable for this
case.
Signed-off-by: NHerton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Cc: stable@vger.kernel.org
Acked-by: NNicolas Pitre <nico@linaro.org>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The gpmi-nand driver uses virt_addr_valid() to check whether a buffer
is suitable for dma. If it's not, a driver allocated buffer is used
instead. Then after a page read the driver allocated buffer must be
copied to the user supplied buffer. This does not happen since commit
7725cc85.

This patch fixes the issue. The bug is encountered with UBI which uses a
vmalloced buffer for the volume table.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Tested-by: snijsure@grid-net.com
Acked-by: NHuang Shijie <b32955@freescale.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The following commit changes the function used to copy from/to
the hardware buffer to memcpy_[from|to]io. This does not work
since the hardware cannot handle the byte accesses used by these
functions. Instead of reverting this patch introduce 32bit
correspondents of these functions.

| commit 5775ba36ea9c760c2d7e697dac04f2f7fc95aa62
| Author: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
| Date:   Tue Apr 24 10:05:22 2012 +0200
|
|    mtd: mxc_nand: fix several sparse warnings about incorrect address space
|
|     Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
|     Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The intent here was clearly to set result to true if the 0x40000000 flag
was set.  But instead there was a | vs & typo and we always set result
to true.

Artem: check the spec at
wiki.laptop.org/images/5/5c/88ALP01_Datasheet_July_2007.pdf
and this fix looks correct.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Commit "e9b4cf20 UBI: fix debugfs-less systems support" fixed one
regression but introduced a different regression - the debugfs is now always
compiled out. Root cause: IS_ENABLED() arguments should be used with the
CONFIG_* prefix.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

The standard (see BSS_SECTION() in <asm-generic/vmlinux.lds.h> and
<asm-generic/sections.h>) symbol for the end of BSS is __bss_stop.
This allows to remove all local declarations that have been added to
several architectures just to please CONFIG_MTD_UCLINUX.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NPaul Mundt <lethal@linux-sh.org>
Acked-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NMichal Simek <monstr@monstr.eu>
Acked-by: NGreg Ungerer <gerg@uclinux.org>

Provide an iterator to receive the log buffer content, and convert all
kmsg_dump() users to it.

The structured data in the kmsg buffer now contains binary data, which
should no longer be copied verbatim to the kmsg_dump() users.

The iterator should provide reliable access to the buffer data, and also
supports proper log line-aware chunking of data while iterating.
Signed-off-by: NKay Sievers <kay@vrfy.org>
Tested-by: NTony Luck <tony.luck@intel.com>
Reported-by: NAnton Vorontsov <anton.vorontsov@linaro.org>
Tested-by: NAnton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As of edbc4540 [mtd: driver _read() returns max_bitflips; mtd_read()
returns -EUCLEAN], 'mtd->bitflip_threshold' must be set for mtd devices
having ECC, prior any 'mtd_read()' call.
Otherwise, 'mtd_read()' will falsely return -EUCLEAN.

Normally, 'mtd->bitflip_threshold' is initialized when the MTD is added.

However, this is too late for NAND MTDs, as 'scan_bbt()' is invoked
prior the existing initialization of 'mtd->bitflip_threshold'.

This is a problem since 'scan_bbt()' calls 'mtd_read()', in the case
of a flash-based bad block table.
It resulted in a falsely reported bitflips indication during BBT read,
which lead to constant scrubbing of the flash BBT blocks.

Initialize 'mtd->bitflip_threshold' to its default value (if not already
set by the driver), prior to invocation of 'scan_bbt()'.
Reported-by: NSascha Hauer <s.hauer@pengutronix.de>
Tested-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Commit "62f38455 UBI: modify ubi_wl_flush function to clear work queue for a lnum"
takes the 'work_sem' semaphore in write mode for the entire loop, which is not
very good because it will block other workers for potentially long time. We do
not need to have it in write mode - read mode is enough, and we do not need to
hole it over the entire loop. So this patch turns changes the locking: takes
'work_sem' in read mode and pushes it down to the loop.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

Commit "aa44d1d3 UBI: remove Kconfig debugging option" broke UBI and it
refuses to initialize if debugfs (CONFIG_DEBUG_FS) is disabled. I incorrectly
assumed that debugfs files creation function will return success if debugfs
is disabled, but they actually return -ENODEV. This patch fixes the issue.
Reported-by: NPaul Parsons <lost.distance@yahoo.com>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Tested-by: NPaul Parsons <lost.distance@yahoo.com>

Since commit 6a918bad, the mxc_nand driver
fails with:

Driver must set ecc.strength when using hardware ECC

This is because nand_scan_tail checks for correct ecc strength
settings, so we must set them up before nand_scan_tail.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Cc: stable@vger.kernel.org [3.4+]
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

The 'mtd_writev' interface calls the function assigned
to the '_write' field of a given mtd device if that is
not NULL. The block2mtd driver sets the '_writev' field
to the 'mtd_writev' function itself and thus causes a
endless loop.

This is caused by 1dbebd32
(mtd: harmonize mtd_writev usage).

Remove the assignment from the block2mtd driver to fix the
issue.
Signed-off-by: NGabor Juhos <juhosg@openwrt.org>
Cc: stable@kernel.org [3.3+]
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

Fix an issue which was introduced by the recent addition of ecc.strength.

The ecc.strength wasn't set in gpmi-nand, resulting in the following crash:
[    2.550000] kernel BUG at drivers/mtd/nand/nand_base.c:3347!
...
[    2.550000] [<c020841c>] (nand_scan_tail+0x328/0x650) from [<c02f68e0>] (gpmi_nand_probe+0x43c/0x5a4)
[    2.550000] [<c02f68e0>] (gpmi_nand_probe+0x43c/0x5a4) from [<c01f6618>] (platform_drv_probe+0x14/0x18)
[    2.550000] [<c01f6618>] (platform_drv_probe+0x14/0x18) from [<c01f55b0>] (driver_probe_device+0x74/0x1fc)
[    2.550000] [<c01f55b0>] (driver_probe_device+0x74/0x1fc) from [<c01f57cc>] (__driver_attach+0x94/0x98)
[    2.550000] [<c01f57cc>] (__driver_attach+0x94/0x98) from [<c01f3d40>] (bus_for_each_dev+0x50/0x80)
[    2.550000] [<c01f3d40>] (bus_for_each_dev+0x50/0x80) from [<c01f4e18>] (bus_add_driver+0x188/0x25c)
[    2.550000] [<c01f4e18>] (bus_add_driver+0x188/0x25c) from [<c01f5a70>] (driver_register+0x78/0x138)
[    2.550000] [<c01f5a70>] (driver_register+0x78/0x138) from [<c043dc7c>] (gpmi_nand_init+0xc/0x30)
[    2.550000] [<c043dc7c>] (gpmi_nand_init+0xc/0x30) from [<c0008824>] (do_one_initcall+0x108/0x17c)
[    2.550000] [<c0008824>] (do_one_initcall+0x108/0x17c) from [<c042a8b8>] (kernel_init+0xfc/0x1bc)
[    2.550000] [<c042a8b8>] (kernel_init+0xfc/0x1bc) from [<c000fab4>] (kernel_thread_exit+0x0/0x8)
Signed-off-by: NMarek Vasut <marex@denx.de>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

MTD_OF_PARTS and the default setting is not working due to using 'Y'
instead of 'y', introduced in commit
d6137bad. This made our board, and
possibly other boards using DTS defined partitions and not having
CONFIG_MTD_OF_PARTS=y defined in the defconfig, fail to mount root.
Signed-off-by: NFrank Svendsboe <frank.svendsboe@gmail.com>
Cc: stable@kernel.org [3.2+]
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

It seems there is a bug in scan_read_raw_oob() in nand_bbt.c which
should cause wrong functioning of NAND_BBT_SCANALLPAGES option.

Artem: the patch did not apply and I had to amend it a bit.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org

Corner case reads do not work, and return false data and
ECC. This case is typically seen in a ubifs usage, with a
read of type:
 - docg3 docg3: doc_read_oob(from=14882415, mode=1,
 data=(c30eca40:12), oob=(  (null):0))

This results in the following reads:
 - docg3 docg3: doc_read_data_area(buf=  (null), len=111)
 - docg3 docg3: doc_read_data_area(buf=c30eca40, len=12)
 - docg3 docg3: doc_read_data_area(buf=  (null), len=389)
 - docg3 docg3: doc_read_data_area(buf=  (null), len=0)
 - docg3 docg3: doc_read_data_area(buf=  (null), len=16)

If we suppose that the pages content is :
 - bytes 0 .. 111   : 0x0a
 - bytes 112 .. 255 : 0x0f
Then the returned bytes will be :
 - 111 times 0x0a (correct)
 - 0x0a 2 times and 0x0f 10 times (incorrect, should be
 0x0a,0x0f)
 - 0x0f 389 times (correct)
 - nothing
 - correct OOB

The reason seams that the first 111 bytes read ends between
the 2 docg3 planes, and that the first following read (in
the 12 bytes sequence, read of 16 bit word) returns the byte
of the rightmost plane duplicated in high and lower byte of
the word.

Fix this behaviour by ensuring that if the previous read
ended up in-between the 2 planes, there will be a first 1
byte read to get back to the beginning of leftmost plane.
Signed-off-by: NRobert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

When running on a FALC-ON SoC, we need to check the bootstrap options to see
if NOR is available.
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Acked-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: linux-mtd@lists.infradead.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3815/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Adds bindings for OF and make use of module_platform_driver for lantiq
based socs.
Signed-off-by: NJohn Crispin <blogic@openwrt.org>
Acked-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: linux-mtd@lists.infradead.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3811/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch modifies ubi_wl_flush to force the erasure of
particular volume id / logical eraseblock number pairs. Previous functionality
is preserved when passing UBI_ALL for both values. The locations where ubi_wl_flush
were called are appropriately changed: ubi_leb_erase only flushes for the
erased LEB, and ubi_create_volume forces only flushing for its volume id.
External code can call this new feature via the new function ubi_flush() added
to kapi.c, which simply passes through to ubi_wl_flush().

This was tested by disabling the call to do_work in ubi thread, which results
in the work queue remaining unless explicitly called to remove. UBIFS was
changed to call ubifs_leb_change 50 times for four different LEBs. Then the
new function was called to clear the queue: passing wrong volume ids / lnum,
correct ones, and finally UBI_ALL for both to ensure it was finally all
cleard. The work queue was dumped each time and the selective removal
of the particular LEB numbers was observed. Extra checks were enabled and
ubifs's integck was also run. Finally, the drive was repeatedly filled and
emptied to ensure that the queue was cleared normally.

Artem: amended the patch.
Signed-off-by: NJoel Reardon <reardonj@inf.ethz.ch>
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>

Joel will use it in his 'ubi_flush()' extention to specify all eraseblocks.
Also amend the comment for UBI_UNKNOWN - it is used beyond attaching info
structure now.
Signed-off-by: NArtem Bityutskiy <artem.bityutskiy@linux.intel.com>