mtd: Support kmsg dumper based on pstore/blk

This introduces mtdpstore, which is similar to mtdoops but more
powerful. It uses pstore/blk, and aims to store panic and oops logs to
a flash partition,

mtd: Support kmsg dumper based on pstore/blk

This introduces mtdpstore, which is similar to mtdoops but more
powerful. It uses pstore/blk, and aims to store panic and oops logs to
a flash partition, where pstore can later read back and present as files
in the mounted pstore filesystem.

To make mtdpstore work, the "blkdev" of pstore/blk should be set
as MTD device name or MTD device number. For more details, see
Documentation/admin-guide/pstore-blk.rst

This solves a number of issues:
- Work duplication: both of pstore and mtdoops do the same job storing
panic/oops log. They have very similar logic, registering to kmsg
dumper and storing logs to several chunks one by one.
- Layer violations: drivers should provides methods instead of polices.
MTD should provide read/write/erase operations, and allow a higher
level drivers to provide the chunk management, kmsg dump
configuration, etc.
- Missing features: pstore provides many additional features, including
presenting the logs as files, logging dump time and count, and
supporting other frontends like pmsg, console, etc.

Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-11-keescook@chromium.org/
Link: https://lore.kernel.org/r/1589266715-4168-1-git-send-email-liaoweixiong@allwinnertech.com
Signed-off-by: Kees Cook <keescook@chromium.org>

show more ...

mtd: parsers: Move CMDLINE parser

This moves the CMDLINE partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off

mtd: parsers: Move CMDLINE parser

This moves the CMDLINE partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

show more ...

mtd: parsers: Move OF parser

This moves the OF/device tree partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-o

mtd: parsers: Move OF parser

This moves the OF/device tree partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

show more ...

mtd: parsers: Move BCM63xx parser

This moves the BCM63xx partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off

mtd: parsers: Move BCM63xx parser

This moves the BCM63xx partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

show more ...

mtd: parsers: Move BCM47xx parser

This moves the BCM47xx partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off

mtd: parsers: Move BCM47xx parser

This moves the BCM47xx partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

show more ...

mtd: parsers: Move TI AR7 parser

This moves the TI AR7 partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-b

mtd: parsers: Move TI AR7 parser

This moves the TI AR7 partition parser down into the
parser subdirectory. No functional change.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

show more ...

mtd: Add support for HyperBus memory devices

Cypress' HyperBus is Low Signal Count, High Performance Double Data Rate
Bus interface between a host system master and one or more slave
interfaces. Hyp

mtd: Add support for HyperBus memory devices

Cypress' HyperBus is Low Signal Count, High Performance Double Data Rate
Bus interface between a host system master and one or more slave
interfaces. HyperBus is used to connect microprocessor, microcontroller,
or ASIC devices with random access NOR flash memory (called HyperFlash)
or self refresh DRAM (called HyperRAM).

Its a 8-bit data bus (DQ[7:0]) with Read-Write Data Strobe (RWDS)
signal and either Single-ended clock(3.0V parts) or Differential clock
(1.8V parts). It uses ChipSelect lines to select b/w multiple slaves.
At bus level, it follows a separate protocol described in HyperBus
specification[1].

HyperFlash follows CFI AMD/Fujitsu Extended Command Set (0x0002) similar
to that of existing parallel NORs. Since HyperBus is x8 DDR bus,
its equivalent to x16 parallel NOR flash with respect to bits per clock
cycle. But HyperBus operates at >166MHz frequencies.
HyperRAM provides direct random read/write access to flash memory
array.

But, HyperBus memory controllers seem to abstract implementation details
and expose a simple MMIO interface to access connected flash.

Add support for registering HyperFlash devices with MTD framework. MTD
maps framework along with CFI chip support framework are used to support
communicating with flash.

Framework is modelled along the lines of spi-nor framework. HyperBus
memory controller (HBMC) drivers calls hyperbus_register_device() to
register a single HyperFlash device. HyperFlash core parses MMIO access
information from DT, sets up the map_info struct, probes CFI flash and
registers it with MTD framework.

Some HBMC masters need calibration/training sequence[3] to be carried
out, in order for DLL inside the controller to lock, by reading a known
string/pattern. This is done by repeatedly reading CFI Query
Identification String. Calibration needs to be done before trying to detect
flash as part of CFI flash probe.

HyperRAM is not supported at the moment.

HyperBus specification can be found at[1]
HyperFlash datasheet can be found at[2]

[1] https://www.cypress.com/file/213356/download
[2] https://www.cypress.com/file/213346/download
[3] http://www.ti.com/lit/ug/spruid7b/spruid7b.pdf
Table 12-5741. HyperFlash Access Sequence

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>

show more ...

mtd: afs: Move AFS partition parser to parsers subdir

This moves the AFS (ARM Firmware Suite) partition parser
for NOR flash down into the parsers subdirectory.

Signed-off-by: Linus Walleij <linus.

mtd: afs: Move AFS partition parser to parsers subdir

This moves the AFS (ARM Firmware Suite) partition parser
for NOR flash down into the parsers subdirectory.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Richard Weinberger <richard@nod.at>

show more ...

mtd: Move Redboot partition parser

This moves the Redboot partition parser down to the parsers
subdirectory.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Boris Brezillon <

mtd: Move Redboot partition parser

This moves the Redboot partition parser down to the parsers
subdirectory.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

show more ...

mtd: Move onenand code base to drivers/mtd/nand/onenand

Move onenand code base to the drivers/mtd/nand directory in the hope
that someday someone will patch it to use the generic NAND helpers.
If it

mtd: Move onenand code base to drivers/mtd/nand/onenand

Move onenand code base to the drivers/mtd/nand directory in the hope
that someday someone will patch it to use the generic NAND helpers.
If it never happens, at least we'll have all NAND related support in a
single directory and not spread over the drivers/mtd/ directory.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>

show more ...

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

mtd: extract TRX parser out of bcm47xxpart into a separated module

This makes TRX parsing code reusable with other platforms and parsers.

Please note this patch doesn't really change anything in th

mtd: extract TRX parser out of bcm47xxpart into a separated module

This makes TRX parsing code reusable with other platforms and parsers.

Please note this patch doesn't really change anything in the existing
code, just moves it. There is still some place for improvement (e.g.
working on non-hacky method of checking rootfs format) but it's not
really a subject of this change.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

show more ...

mtd: spi-nor: shorten Kconfig naming

Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Acked-by: Huang Shijie <b32955@freescale.com>

mtd: spi-nor: add the framework for SPI NOR

This patch cloned most of the m25p80.c. In theory, it adds a new spi-nor layer.

Before this patch, the layer is like:

MTD
--

mtd: spi-nor: add the framework for SPI NOR

This patch cloned most of the m25p80.c. In theory, it adds a new spi-nor layer.

Before this patch, the layer is like:

MTD
------------------------
m25p80
------------------------
spi bus driver
------------------------
SPI NOR chip

After this patch, the layer is like:
MTD
------------------------
spi-nor
------------------------
m25p80
------------------------
spi bus driver
------------------------
SPI NOR chip

With the spi-nor controller driver(Freescale Quadspi), it looks like:
MTD
------------------------
spi-nor
------------------------
fsl-quadspi
------------------------
SPI NOR chip

New APIs:
spi_nor_scan: used to scan a spi-nor flash.

Signed-off-by: Huang Shijie <b32955@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
[Brian: rebased to include additional m25p_ids[] entry]
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

show more ...

mtd: merge mtdchar module with mtdcore

The MTD subsystem has historically tried to be as configurable as possible. The
side-effect of this is that its configuration menu is rather large, and we are

mtd: merge mtdchar module with mtdcore

The MTD subsystem has historically tried to be as configurable as possible. The
side-effect of this is that its configuration menu is rather large, and we are
gradually shrinking it. For example, we recently merged partitions support with
the mtdcore.

This patch does the next step - it merges the mtdchar module to mtdcore. And in
this case this is not only about eliminating too fine-grained separation and
simplifying the configuration menu. This is also about eliminating seemingly
useless kernel module.

Indeed, mtdchar is a module that allows user-space making use of MTD devices
via /dev/mtd* character devices. If users do not enable it, they simply cannot
use MTD devices at all. They cannot read or write the flash contents. Is it a
sane and useful setup? I believe not. And everyone just enables mtdchar.

Having mtdchar separate is also a little bit harmful. People sometimes miss the
fact that they need to enable an additional configuration option to have
user-space MTD interfaces, and then they wonder why on earth the kernel does
not allow using the flash? They spend time asking around.

Thus, let's just get rid of this module and make it part of mtd core.

Note, mtdchar had additional configuration option to enable OTP interfaces,
which are present on some flashes. I removed that option as well - it saves a
really tiny amount space.

[dwmw2: Strictly speaking, you can mount file systems on MTD devices just
fine without the mtdchar (or mtdblock) devices; you just can't do
other manipulations directly on the underlying device. But still I
agree that it makes sense to make this unconditional. And Yay! we
get to kill off an instance of checking CONFIG_foo_MODULE, which is
an abomination that should never happen.]

Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

mtd: bcm47part driver for BCM47XX chipsets

This driver provides parser detecting partitions on BCM47XX flash
memories. It has many differences in comparison to BCM63XX, like:
1) Different CFE with n

mtd: bcm47part driver for BCM47XX chipsets

This driver provides parser detecting partitions on BCM47XX flash
memories. It has many differences in comparison to BCM63XX, like:
1) Different CFE with no more trivial MAGICs
2) More partitions types (board_data, ML, POT)
3) Supporting more than 1 flash on a device
which resulted in decision of writing new parser.

It uses generic mtd interface and was successfully tested with Netgear
WNDR4500 router which has 2 flash memories: serial one and NAND one.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

mtd: maps: bcm963xx-flash: make CFE partition parsing an mtd parser

Recent BCM63XX devices support a variety of flash types (parallel, SPI,
NAND) and share the partition layout. To prevent code dupl

mtd: maps: bcm963xx-flash: make CFE partition parsing an mtd parser

Recent BCM63XX devices support a variety of flash types (parallel, SPI,
NAND) and share the partition layout. To prevent code duplication make
the CFE partition parsing code a stand alone mtd parser to allow SPI or
NAND flash drivers to use it.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

mtd: make ofpart buildable as a separate module

As ofpart now uses a standard mtd partitions parser interface, make it
buildable as a separate module. Also provide MODULE_DESCRIPTION and
MODULE_AUTH

mtd: make ofpart buildable as a separate module

As ofpart now uses a standard mtd partitions parser interface, make it
buildable as a separate module. Also provide MODULE_DESCRIPTION and
MODULE_AUTHOR for this module.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Artem Bityutskiy <dedekind1@gmail.com>

show more ...

mtd: kill CONFIG_MTD_PARTITIONS

Now that none of the drivers use CONFIG_MTD_PARTITIONS we can remove
it from Kconfig and the last remaining uses.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Sig

mtd: kill CONFIG_MTD_PARTITIONS

Now that none of the drivers use CONFIG_MTD_PARTITIONS we can remove
it from Kconfig and the last remaining uses.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

mtd: Add mtdswap block driver

Add a driver for allowing an mtd device to be used as a block device for
swapping. The block device is volatile, and the mapping of swapped pages
is not stored on flash

mtd: Add mtdswap block driver

Add a driver for allowing an mtd device to be used as a block device for
swapping. The block device is volatile, and the mapping of swapped pages
is not stored on flash.

Signed-off-by: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Tested-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

mtd: make MTD_CONCAT support mandatory

Move mtdconcat to be an integral part of the mtd core. It's a tiny bit
of code, which bears 'say Y if you don't know what to do' note in the
Kconfig. OTOH ther

mtd: make MTD_CONCAT support mandatory

Move mtdconcat to be an integral part of the mtd core. It's a tiny bit
of code, which bears 'say Y if you don't know what to do' note in the
Kconfig. OTOH there are several ugly ifdefs depending on the MTD_CONCAT.
So, making MTD_CONCAT support mandatory will allow us to clean up code a
lot.

Kconfig entry is changed to be a bool defaulting to Y, so all code
pieces depending on it, will have MTD_CONCAT Kconfig symbol and
CONFIG_MTD_CONCAT define. This will be removed in one of next patches.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Acked-by: Stefan Roese <sr@denx.de>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

mtd: Fix MTD_OF_PARTS for all arch and minor tidy of MTD_PARTITIONS

MTD_OF_PARTS should be possible on all architectures, not just
powerpc and microblaze, and it probably should not be a user
select

mtd: Fix MTD_OF_PARTS for all arch and minor tidy of MTD_PARTITIONS

MTD_OF_PARTS should be possible on all architectures, not just
powerpc and microblaze, and it probably should not be a user
selectable option. Neither does it need to be in a separate module.

Also, rework MTD Kconfig to group options dependant on MTD_PARTITIONS
into a if/endif block. Do the same for MTD_REDBOOT_PARTS.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

Move mtd_bdi_*mappable to mtdcore.c

Removes one .h and one .c file that are never used outside of
mtdcore.c.

Signed-off-by: Joern Engel <joern@logfs.org>

Edited to remove on leftover debug define.

Move mtd_bdi_*mappable to mtdcore.c

Removes one .h and one .c file that are never used outside of
mtdcore.c.

Signed-off-by: Joern Engel <joern@logfs.org>

Edited to remove on leftover debug define.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

show more ...

mtd: Add new SmartMedia/xD FTL

This implements new readwrite SmartMedia/xd FTL.

mtd driver must have support proper ECC and badblock verification
based on oob parts for 512 bytes nand.

Also mtd dr

mtd: Add new SmartMedia/xD FTL

This implements new readwrite SmartMedia/xd FTL.

mtd driver must have support proper ECC and badblock verification
based on oob parts for 512 bytes nand.

Also mtd driver must define read_oob and write_oob, which are used
to read and write both data and oob together.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...

NOMMU: Present backing device capabilities for MTD chardevs

Present backing device capabilities for MTD character device files to allow
NOMMU mmap to do direct mapping where possible.

Signed-off-by

NOMMU: Present backing device capabilities for MTD chardevs

Present backing device capabilities for MTD character device files to allow
NOMMU mmap to do direct mapping where possible.

Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

show more ...