This helps to detect cases where an user copies an UBI image to
another target with different bad blocks.
Signed-off-by: NRichard Weinberger <richard@nod.at>

Introduce a new list to the UBI attach information
object to be able to deal better with old and corrupted
Fastmap eraseblocks.
Also move more Fastmap specific code into fastmap.c.
Signed-off-by: NRichard Weinberger <richard@nod.at>

Signed-off-by: NRichard Weinberger <richard@nod.at>

This makes the logic more easy to follow.
Signed-off-by: NRichard Weinberger <richard@nod.at>

Signed-off-by: NRichard Weinberger <richard@nod.at>

When the volume resize operation shrinks a volume,
LEBs will be unmapped. Since unmapping will not erase these
LEBs immediately we have to wait for that operation to finish.
Otherwise in case of a power cut right after writing the new
volume table the UBI attach process can find more LEBs than the
volume table knows. This will render the UBI image unattachable.

Fix this issue by waiting for erase to complete and write the new
volume table afterward.

Cc: <stable@vger.kernel.org>
Reported-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

We cannot use ubi_* logging functions before the UBI
object is initialized.

Cc: <stable@vger.kernel.org>
Fixes: 32608703 ("UBI: Extend UBI layer debug/messaging capabilities")
Signed-off-by: NRichard Weinberger <richard@nod.at>

There is no need to call get/put on the module
reference in gluebi_get/put_device() callbacks.
Since mtd->owner is the gluebi module itself
mtdcore.c will take care of proper refcounting
in __get/put_mtd_device() before executing the
callbacks.
Signed-off-by: NRichard Weinberger <richard@nod.at>

Install the UBI device object before we arm sysfs.
Otherwise udev tries to read sysfs attributes before UBI is ready and
udev rules will not match.

Cc: <stable@vger.kernel.org>
Signed-off-by: NIosif Harutyunov <iharutyunov@sonicwall.com>
[rw: massaged commit message]
Signed-off-by: NRichard Weinberger <richard@nod.at>

When reading the vid hdr from the device UBI always reads a whole
page. Instead, read only the data we actually need and speed up
attachment of UBI devices by potentially making use of reading
subpages if the NAND driver supports it.

Since the VID header may be at offset vid_hdr_shift in the page and
we can only read from the beginning of a page we have to add that
offset to the read size.
Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: NRichard Weinberger <richard@nod.at>

commit c9711ec5 ("mtd: nand: omap: Clean up device tree support")
removes the check for the old elm phandle binding.
Add it again to keep backward compatibility.

Fixes: commit c9711ec5 ("mtd: nand: omap: Clean up device tree support")
Signed-off-by: NTeresa Remmet <t.remmet@phytec.de>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

recover_peb() was never power cut aware,
if a power cut happened right after writing the VID header
upon next attach UBI would blindly use the new partial written
PEB and all data from the old PEB is lost.

In order to make recover_peb() power cut aware, write the new
VID with a proper crc and copy_flag set such that the UBI attach
process will detect whether the new PEB is completely written
or not.
We cannot directly use ubi_eba_atomic_leb_change() since we'd
have to unlock the LEB which is facing a write error.

Cc: stable@vger.kernel.org
Reported-by: NJörg Pfähler <pfaehler@isse.de>
Reviewed-by: NJörg Pfähler <pfaehler@isse.de>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Directly accessing inode fields bypasses ->getattr()
and can cause problems when the underlying filesystem
does not have the default ->getattr() implementation.

So instead of obtaining the backing inode via d_backing_inode()
use vfs_getattr() and obtain what we need from the kstat struct.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NRichard Weinberger <richard@nod.at>

This reverts commit 87f15d4a.

vfs_stat() can only be used on user supplied buffers.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NRichard Weinberger <richard@nod.at>

This reverts commit 322ea0bb.

vfs_stat() can only be used on user supplied buffers.
UBI's kapi.c is the API to the kernel and therefore vfs_stat()
is inappropriate.

This solves the problem that mounting any UBIFS will immediately
fail with -EINVAL.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NRichard Weinberger <richard@nod.at>

This reverts commit 5ddc7bd4 ("mtd: atmel_nand: Support variable
RB_EDGE interrupts")

Because for current SoCs, the RB_EDGE3(i.e. bit 27) of HSMC_SR
register does not exist, the RB_EDGE0 (i.e. bit 24) is the ready/busy
line edge status bit. It is a datasheet bug.

Cc: <stable@vger.kernel.org>
Fixes: commit 5ddc7bd4 ("mtd: atmel_nand: Support variable RB_EDGE interrupts")
Signed-off-by: NWenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

Ezequiel reported that he's facing UBI going into read-only
mode after power cut. It turned out that this behavior happens
only when updating a static volume is interrupted and Fastmap is
used.

A possible trace can look like:
ubi0 warning: ubi_io_read_vid_hdr [ubi]: no VID header found at PEB 2323, only 0xFF bytes
ubi0 warning: ubi_eba_read_leb [ubi]: switch to read-only mode
CPU: 0 PID: 833 Comm: ubiupdatevol Not tainted 4.6.0-rc2-ARCH #4
Hardware name: SAMSUNG ELECTRONICS CO., LTD. 300E4C/300E5C/300E7C/NP300E5C-AD8AR, BIOS P04RAP 10/15/2012
0000000000000286 00000000eba949bd ffff8800c45a7b38 ffffffff8140d841
ffff8801964be000 ffff88018eaa4800 ffff8800c45a7bb8 ffffffffa003abf6
ffffffff850e2ac0 8000000000000163 ffff8801850e2ac0 ffff8801850e2ac0
Call Trace:
[<ffffffff8140d841>] dump_stack+0x63/0x82
[<ffffffffa003abf6>] ubi_eba_read_leb+0x486/0x4a0 [ubi]
[<ffffffffa00453b3>] ubi_check_volume+0x83/0xf0 [ubi]
[<ffffffffa0039d97>] ubi_open_volume+0x177/0x350 [ubi]
[<ffffffffa00375d8>] vol_cdev_open+0x58/0xb0 [ubi]
[<ffffffff8124b08e>] chrdev_open+0xae/0x1d0
[<ffffffff81243bcf>] do_dentry_open+0x1ff/0x300
[<ffffffff8124afe0>] ? cdev_put+0x30/0x30
[<ffffffff81244d36>] vfs_open+0x56/0x60
[<ffffffff812545f4>] path_openat+0x4f4/0x1190
[<ffffffff81256621>] do_filp_open+0x91/0x100
[<ffffffff81263547>] ? __alloc_fd+0xc7/0x190
[<ffffffff812450df>] do_sys_open+0x13f/0x210
[<ffffffff812451ce>] SyS_open+0x1e/0x20
[<ffffffff81a99e32>] entry_SYSCALL_64_fastpath+0x1a/0xa4

UBI checks static volumes for data consistency and reads the
whole volume upon first open. If the volume is found erroneous
users of UBI cannot read from it, but another volume update is
possible to fix it. The check is performed by running
ubi_eba_read_leb() on every allocated LEB of the volume.
For static volumes ubi_eba_read_leb() computes the checksum of all
data stored in a LEB. To verify the computed checksum it has to read
the LEB's volume header which stores the original checksum.
If the volume header is not found UBI treats this as fatal internal
error and switches to RO mode. If the UBI device was attached via a
full scan the assumption is correct, the volume header has to be
present as it had to be there while scanning to get known as mapped.
If the attach operation happened via Fastmap the assumption is no
longer correct. When attaching via Fastmap UBI learns the mapping
table from Fastmap's snapshot of the system state and not via a full
scan. It can happen that a LEB got unmapped after a Fastmap was
written to the flash. Then UBI can learn the LEB still as mapped and
accessing it returns only 0xFF bytes. As UBI is not a FTL it is
allowed to have mappings to empty PEBs, it assumes that the layer
above takes care of LEB accounting and referencing.
UBIFS does so using the LEB property tree (LPT).
For static volumes UBI blindly assumes that all LEBs are present and
therefore special actions have to be taken.

The described situation can happen when updating a static volume is
interrupted, either by a user or a power cut.
The volume update code first unmaps all LEBs of a volume and then
writes LEB by LEB. If the sequence of operations is interrupted UBI
detects this either by the absence of LEBs, no volume header present
at scan time, or corrupted payload, detected via checksum.
In the Fastmap case the former method won't trigger as no scan
happened and UBI automatically thinks all LEBs are present.
Only by reading data from a LEB it detects that the volume header is
missing and incorrectly treats this as fatal error.
To deal with the situation ubi_eba_read_leb() from now on checks
whether we attached via Fastmap and handles the absence of a
volume header like a data corruption error.
This way interrupted static volume updates will correctly get detected
also when Fastmap is used.

Cc: <stable@vger.kernel.org>
Reported-by: NEzequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: NEzequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Set free_count to zero before walking through ai->erase list
in wl_init().

Found in U-Boot as U-Boot has no workqueue/threads, it immediately
calls erase_worker(), which increase for each erased block
free_count. Without this patch, free_count gets after
this initialized to zero in wl_init(), so the free_count
variable always has the maybe wrong value 0 in U-Boot.
Signed-off-by: NHeiko Schocher <hs@denx.de>
Reviewed-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

My static checker complains that "val" is uninitialized when kstrtoint()
fails.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

My static checker says that "err" can be uninitialized if
"vol->reserved_pebs" is <= 0.  I don't think that can happen but
returning a literal is cleaner anyway.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Signed-off-by: Nz00189512 <abc.zhangliang@huawei.com>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Drop this paranoia check from the old days.
If our MTD driver or the flash is so bad that we even cannot
trust it to write data we have bigger problems.

If one really does not trust the flash and wants write-verify
she can enable UBI io checks using debugfs.
Signed-off-by: NRichard Weinberger <richard@nod.at>

On serious situations, UBI may detect serious device corruption,
and switch to read-only mode to protect the data and allow debugging.
This commit exposes this ro-mode on sysfs, so it can be obtained
by userspace tools.
Signed-off-by: NEzequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: NRichard Weinberger <richard@nod.at>

Also note the GigaDevice JEDEC ID.

No write-protect support yet, since this flash uses a different status
register layout.

Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Acked-by: NMarek Vasut <marex@denx.de>

Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Acked-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This is more obvious than guessing based on ECC strength. It allows
using NAND on devices with BCH-1 (e.g. D-Link DIR-885L).

This maintains DT backward compatibility by defaulting to Hamming if a
1-bit ECC algorithm is specified without a corresponding algorithm
selection. i.e., to use BCH-1, you must specify:

  nand-ecc-strength = <1>;
  nand-ecc-step-size = <512>;
  nand-ecc-algo = "bch";

Also adds a check to ensure we haven't allowed someone to get by with SW
ECC. If we want to support SW ECC, we need to refactor some other pieces
of this driver.
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>
Tested-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

ECC is only calculated for written pages. As erased pages are not
actively written the ECC is always invalid. For this purpose the
Hardware BCH unit is able to check for erased pages and does not raise
an ECC error in this case. This behaviour can be influenced using the
BCH_MODE register which sets the number of allowed bitflips in an erased
page. Unfortunately the unit is not capable of fixing the bitflips in
memory.

To avoid complete software checks for erased pages, we can simply check
buffers with uncorrectable ECC errors because we know that any erased
page with errors is uncorrectable by the BCH unit.

This patch adds the generic nand_check_erased_ecc_chunk() to gpmi-nand
to correct erased pages. To have the valid data in the buffer before
using them, this patch moves the read_page_swap_end() call before the
ECC status checking for-loop.
Signed-off-by: NMarkus Pargmann <mpa@pengutronix.de>
[Squashed patches by Stefan and Boris to check ECC area]
Tested-by: NStefan Christ <s.christ@phytec.de>
Acked-by: NHan xu <han.xu@nxp.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

So far it was only possible to specify ECC algorithm using "soft" and
"soft_bch" values of nand-ecc-mode prop. There wasn't a way to specify
it for a hardware ECC mode.

Now that we have independent field in NAND subsystem for storing info
about ECC algorithm we may also add support for this new DT property.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This value should not be part of nand_ecc_modes_t as it specifies
algorithm not a mode. We successfully managed to introduce new "algo"
field which is respected now.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

There isn't any difference between handling NAND_ECC_SOFT and
NAND_ECC_SOFT_BCH now. What matters is the new field called "algo".
Please note we're keeping backward DT compatibility. We are still
treating "soft_bch" value as the one setting Hamming algorithm, it's
just handled in of_get_nand_ecc_algo now.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Now we have all drivers properly setting this new field we can start
using it. For a very short period of time we should support both values:
NAND_ECC_SOFT and NAND_ECC_SOFT_BCH treating them the same. It's because
of_get_nand_ecc_mode may still be setting NAND_ECC_SOFT_BCH.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

NAND core sets ECC algorithm in algo field now and it should be
preferred over the mode field. This also prepares driver for dropping
NAND_ECC_SOFT_BCH.
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This is part of process deprecating NAND_ECC_SOFT_BCH (and switching to
enum nand_ecc_algo).
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This is part of process deprecating NAND_ECC_SOFT_BCH (and switching to
enum nand_ecc_algo).
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This is part of process deprecating NAND_ECC_SOFT_BCH (and switching to
enum nand_ecc_algo).
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

This is part of process deprecating NAND_ECC_SOFT_BCH (and switching to
enum nand_ecc_algo).
Signed-off-by: NRafał Miłecki <zajec5@gmail.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Based on DMA documentation and testing using high memory buffer when doing
dma transfers can lead to various issues including kernel panics.

To workaround this simply use cpu copy.
Signed-off-by: NFranklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

The prefetch engine sends a dma request once a FIFO threshold has
been met. No other requests are received until the previous request
is handled.

Starting a dma transfer (dma_async_issue_pending) results in any
previous event for the dma channel to be cleared. Therefore, starting
the prefetch engine before initiating the dma transfer may result in
the prefetch triggering a dma request but instead of it being handled
it can end up being cleared. This will result in a hang since the code
will continue to wait for the dma request to complete.

By initiating the dma request before enabling the prefetch engine this
race condition is avoided and no dma request are missed/cleared.
Signed-off-by: NFranklin S Cooper Jr <fcooper@ti.com>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Add __init attribute on functions that are only called from other __init
functions and that are not inlined, at least with gcc version 4.8.4 on an
x86 machine with allyesconfig.  Currently, the functions are put in the
.text.unlikely segment.  Declaring them as __init will cause them to be
put in the .init.text and to disappear after initialization.

The result of objdump -x on the functions before the change is as follows:

000000000000059a l     F .text.unlikely 0000000000000239 alloc_device
000000000000034e l     F .text.unlikely 000000000000002e get_partition_name
00000000000007d3 l     F .text.unlikely 00000000000005da init_nandsim

And after the change it is as follows:

0000000000000029 l     F .init.text	0000000000000234 alloc_device
0000000000000000 l     F .init.text	0000000000000029 get_partition_name
000000000000025d l     F .init.text	00000000000005d5 init_nandsim

Done with the help of Coccinelle.  The semantic patch checks for local
static non-init functions that are called from an __init function and are
not called from any other function.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>

Now that all drivers go through nand_set_flash_node() to parse the generic
NAND properties, we can move all of_get_nand_xxx() helpers in to
nand_base.c, make them static and remove of_mtd.c and of_mtd.h.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>