Commit graph

186 commits

Author SHA1 Message Date
Tobias Deiminger
c623642d29 Adjust gitignore for tools/generated/
Tell git that auto-generated C sources are now exclusively expected
under tools/generated/.

Signed-off-by: Tobias Deiminger <tdmg@linutronix.de>
2023-07-07 16:25:56 -04:00
John Keeping
51e0cacca7 tools: env: update lock path in README
Commit aeb40f1166 ("tools: env: use /run to store lockfile") updated the
path to the lockfile but did not update the documentation to match.

Use the new path in the documentation.

Fixes: aeb40f1166 ("tools: env: use /run to store lockfile")
Signed-off-by: John Keeping <john@metanate.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
2023-04-25 15:31:28 -04:00
Tim Lee
aeb40f1166 tools: env: use /run to store lockfile
According this issue https://github.com/ppp-project/ppp/issues/339.
Eventually, the dt-utils changed lock directory to fix missing /var/lock
directory error then make dt-utils can run normally.

We also have a similar issue with these two utilities fw_printenv and
fw_setenv will failed when the directory /var/lock is non-existent.

We have a custom linux distribution built with yocto (OpenBMC) that
use systemd and it deprecated the /var/lock directory.
More discussion in systemd/systemd#15668.

Thus, we sync with community's solution for uboot/tools/env utilities:
The current location /var/lock is considered legacy (at least by systemd).
Just use /run to store the lockfile and append the usual .lock suffix.

Tested:
Verified /run/lock is now present and fw_printenv can work in OpenBMC.

Signed-off-by: Tim Lee <timlee660101@gmail.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2023-04-06 19:10:05 -04:00
Jaehoon Chung
c059a22b77 tools: env: fw_env: Fix unused-result warning
Fix unused-result warning about fread.

tools/env/fw_env.c: In function ‘find_nvmem_device’:
tools/env/fw_env.c:1751:3: warning: ignoring return value of ‘fread’, declared with attribute warn_unused_result [-Wunused-result]
 1751 |   fread(buf, sizeof(buf), 1, fp);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
2022-12-08 09:25:44 -05:00
Miaoqian Lin
316590db29 tools: env: Fix missing closedir in ubi_get_volnum_by_name
The function calls opendir() but missing the corresponding
closedir() before exit the function.
Add missing closedir() to fix it.

Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
2022-09-29 10:10:39 -04:00
Rafał Miłecki
8142c4554f fw_env: add fallback to Linux's NVMEM based access
A new DT binding for describing environment data block has been added in
Linux's commit 5db1c2dbc04c ("dt-bindings: nvmem: add U-Boot environment
variables binding"). Once we get a proper Linux NVMEM driver it'll be
possible to use Linux's binary interface for user-space as documented
in the:
https://www.kernel.org/doc/html/latest/driver-api/nvmem.html

This commits makes fw_env fallback to looking for a compatible NVMEM
device in case config file isn't present. In a long term this may make
config files redundant and avoid code (info) duplication.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2022-07-08 09:06:57 -04:00
Rafał Miłecki
07c79dd5fd fw_env: simplify logic & code paths in the fw_env_open()
Environment variables can be stored in two formats:
1. Single entry with header containing CRC32
2. Two entries with extra flags field in each entry header

For that reason fw_env_open() has two main code paths and there are
pointers for CRC32/flags/data.

Previous implementation was a bit hard to follow:
1. It was checking for used format twice (in reversed order each time)
2. It was setting "environment" global struct fields to some temporary
   values that required extra comments explaining it

This change simplifies that code:
1. It introduces two clear code paths
2. It sets "environment" global struct fields values only once it really
   knows them

To be fair there are *two* crc32() calls now and an extra pointer
variable but that should be cheap enough and worth it.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2022-02-11 11:29:23 -05:00
Rafał Miłecki
f178f7c955 fw_env: make flash_io() take buffer as an argument
It's usually easier to understand code & follow it if all arguments are
passed explicitly. Many coding styles also discourage using global
variables.

Behaviour of flash_io() was a bit unintuitive as it was writing to a
buffer referenced in a global struct. That required developers to
remember how it works and sometimes required hacking "environment"
global struct variable to read data into a proper buffer.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
2022-02-11 11:29:23 -05:00
Joakim Tjernlund
08cf1a5e69 fw_setenv: Unbreak fw_setenv caused by buggy MEMISLOCKED use
Commit "fw_setenv: lock the flash only if it was locked before"
checks for Locked status with uninitialized erase data.
Address by moving the test for MEMISLOCKED.

Fixes: 8a726b852502 ("fw_setenv: lock the flash only if it was locked before")
Signed-off-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
2021-12-20 09:21:48 -05:00
Thibault Ferrante
6628813f9d tools: env: Handle shorter read calls
On some cases, the actual number of bytes read can be shorter
than what was requested. This can be handled gracefully by
taking this difference into account instead of exiting.

Signed-off-by: Thibault Ferrante <thibault.ferrante@gmail.com>
2021-09-02 11:19:58 -04:00
Martin Hundebøll
09779488a9 tools: env: return error if ubi_update_start() fails
The UBI_IOCVOLUP ioctl can fail if exclusive access to the volume isn't
obtained. If this happens, the flush operation doesn't return error,
leaving the caller without knowledge of missing flush.

Fix this by forwarding the error (-1) from ubi_update_start().

Fixes: 34255b92e6 ("tools: env: Add support for direct read/write UBI volumes")
Signed-off-by: Martin Hundebøll <martin@geanix.com>
2021-01-22 16:58:55 -05:00
Simon Glass
7b27e0fe13 tools: env: Avoid an uninited warning with was_locked
Set this variable to 0 to avoid a warning about an unused variable. This
happens on gcc 7.5.0 for me.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-08-05 08:18:34 -04:00
Simon Glass
d9cd4d2a8d tools: env: Fix printf() warning in fw_env
The printf() string produces a warning about %d not matching size_t. Fix
it and put the format string on one line to avoid a checkpatch warning.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-08-05 08:18:34 -04:00
Ivan Mikhaylov
db82015929 fw_setenv: lock the flash only if it was locked before
With current implementation of fw_setenv, it is always locks u-boot-env
region if lock interface is implemented for such mtd device. You can
not control lock of this region with fw_setenv, there is no option for
it in config or in application itself. Because of this situation may
happen problems like in this thread on xilinx forum:
https://forums.xilinx.com/t5/Embedded-Linux/Flash-be-locked-after-use-fw-setenv-from-user-space
/td-p/1027851

A short summary of that link is: some person has issue with some spi
chip which has lock interface but doesn't locks properly which leads to
lock of whole flash memory on lock of u-boot-env region. As resulted
solution hack was added into spi-nor.c driver for this chip with lock
disablement.

Instead fix this problem by adding logic to fw_setenv only lock the
flash if it was already locked when we attempted to use it.

Signed-off-by: Ivan Mikhaylov <fr0st61te@gmail.com>
2020-07-31 10:13:00 -04:00
Harald Seiler
50bb682c5c tools: fw_env: Fix warning when reading too little
When using CONFIG_ENV_IS_IN_FAT and the config-file specifies a size
larger than what U-Boot wrote into the env-file, a confusing error
message is shown:

    $ fw_printenv
    Read error on /boot/uboot.env: Success

Fix this by showing a different error message when read returns too
little data.

Signed-off-by: Harald Seiler <hws@denx.de>
2020-06-02 13:06:14 -04:00
Romain Naour
2aca8804d8 tools/env/fw_env.h: remove env.h
As reported by Nicolas Carrier on the Buildroot mailing list [1],
there is a new build issue while building a program which interacts with
the u-boot environment. This program uses the headers of the ubootenv
library provided by uboot-tools.

This is a recent change from uboot [2] adding "#include <env.h>" to
fw_env.h. Adding env.h require a board configuration to build since
it also include compiler.h (and others uboot internal includes).

env.h include seems not needed since env_set() is not used in fw_env tool.

Nicolas removed env.h from fw_env tool and fixed it's build issue.

This problem is present since uboot v2019.10.

[1] http://lists.busybox.net/pipermail/buildroot/2020-April/280307.html
[2] 9fb625ce05

Reported-by: Nicolas Carrier <nicolas.carrier@orolia.com>
Signed-off-by: Romain Naour <romain.naour@gmail.com>
2020-05-25 11:54:53 -04:00
Rasmus Villemoes
e282c422e0 tools: fw_env: use erasesize from MEMGETINFO ioctl
We have a board with several revisions. The older ones use a nor flash
with 64k erase size, while the newer have a flash with 4k sectors. The
environment size is 8k.

Currently, we have to put a column containing 0x10000 (64k) in
fw_env.config in order for it to work on the older boards. But that
ends up wasting quite a lot of time on the newer boards that could
just erase the 8k occupied by the environment - strace says the 64k
erase takes 0.405 seconds. With this patch, as expected, that's about
an 8-fold better, at 0.043 seconds.

Having different fw_env.config files for the different revisions is
highly impractical, and the correct information is already available
right at our fingertips. So use the erasesize returned by the
MEMGETINFO ioctl when the fourth and fifth columns (sector size and
#sectors, respectively) are absent or contain 0, a case where the
logic previously used to use the environment size as erase size (and
consequently computed ENVSECTORS(dev) as 1).

As I'm only testing this on a NOR flash, I'm only changing the logic
for that case, though I think it should be possible for the other
types as well.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
2020-04-27 14:55:29 -04:00
Rasmus Villemoes
c62e6142b9 fw_setenv: avoid writing environment when nothing has changed
In the case where one deletes an already-non-existing variable, or sets
a variable to the value it already has, there is no point in writing the
environment back, thus reducing wear on the underlying storage
device.

In the case of redundant environments, if the two environments
differ (e.g. because one is corrupt), make sure that any call of
fw_setenv causes the two to become synchronized, even if the fw_setenv
call does not change anything in the good copy.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
2019-12-20 10:02:24 -06:00
Simon Glass
3db7110857 crc32: Use the crc.h header for crc functions
Drop inclusion of crc.h in common.h and use the correct header directly
instead.

With this we can drop the conflicting definition in fw_env.h and rely on
the crc.h header, which is already included.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
2019-12-02 18:23:08 -05:00
Pierre-Jean Texier
7ce01c78dc fw_env: fix build error
The following error appears:

tools/env/fw_env.c:1149:25: error: lvalue required as unary ‘&’ operand
  rc = write(fd, &ENV_REDUND_OBSOLETE, sizeof(ENV_REDUND_OBSOLETE));

Fixes: d3716dd ("env: Rename the redundancy flags")

Signed-off-by: Pierre-Jean Texier <pjtexier@koncepto.io>
Tested-by: Joris Offouga <offougajoris@gmail.com>
Tested-by: Heiko Schocher <hs@denx.de>
Suggested-by: Heiko Schocher <hs@denx.de>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
2019-09-24 17:46:13 -04:00
Pierre-Jean Texier
e184a3b4fd fw_env: remove duplicated definitions
Since commit d3716dd ("env: Rename the redundancy flags"), the
definitions of ENV_REDUND_OBSOLETE & ENV_REDUND_ACTIVE was moved
to env.h.

Fixes:

tools/env/fw_env.c:122:22: error: ‘ENV_REDUND_ACTIVE’ redeclared as different kind of symbol
 static unsigned char ENV_REDUND_ACTIVE = 1;
                      ^~~~~~~~~~~~~~~~~
In file included from tools/env/fw_env.c:13:
include/env.h:63:2: note: previous definition of ‘ENV_REDUND_ACTIVE’ was here
  ENV_REDUND_ACTIVE = 1,
  ^~~~~~~~~~~~~~~~~
tools/env/fw_env.c:127:22: error: ‘ENV_REDUND_OBSOLETE’ redeclared as different kind of symbol
 static unsigned char ENV_REDUND_OBSOLETE;
                      ^~~~~~~~~~~~~~~~~~~
In file included from tools/env/fw_env.c:13:
include/env.h:62:2: note: previous definition of ‘ENV_REDUND_OBSOLETE’ was here
  ENV_REDUND_OBSOLETE = 0,

Signed-off-by: Pierre-Jean Texier <pjtexier@koncepto.io>
Tested-by: Joris Offouga <offougajoris@gmail.com>
Tested-by: Heiko Schocher <hs@denx.de>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
2019-09-24 17:46:13 -04:00
Simon Glass
d3716dd64b env: Rename the redundancy flags
Add an ENV prefix to these two flags so that it is clear what they relate
to. Also move them to env.h since they are part of the public API. Use an
enum rather than a #define to tie them together.

Signed-off-by: Simon Glass <sjg@chromium.org>
2019-08-11 16:43:41 -04:00
Simon Glass
9fb625ce05 env: Move env_set() to env.h
Move env_set() over to the new header file.

Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
2019-08-11 16:43:41 -04:00
Alex Kiernan
a762311a6c fw_env: Add missing write failure check
If flash_write fails, whilst we propagate this up to our caller, we need
to avoid swapping in the new file (if we're on a filesystem) in this
case.

Fixes: dbc3432379 ("tools: env: Implement atomic replace for filesystem")
Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
2019-06-20 10:57:08 -04:00
Philip Molloy
9337a08768 env: add missing newline
Signed-off-by: Philip Molloy <philip@philipmolloy.com>
2019-05-05 08:48:50 -04:00
Björn Stenberg
2b4ea2b344 fw_env: Fix double free
addr0 is being freed twice, leading to segmentation fault

Signed-off-by: Björn Stenberg <bjorn@haxx.se>
2019-04-26 18:58:21 -04:00
Matt Weber
e1df3fa364 include/version.h: workaround sysroot inc order
On some systems the host system or even the cross sysroot can
contain a version.h.  This leads to the wrong file being picked
up and a PLAIN_VERSION undefined error.

This workaround symlinks the version.h into the tool folder to
allow reordering of search folders.

Fixes
http://autobuild.buildroot.net/results/770/7702d5df36a6532aafdbe6e9e62709bbfa058b54/build-end.log
http://autobuild.buildroot.net/results/e34/e3401027d2fb3ce565ca9e2456a427afd3610a87/build-end.log
... additional can be found with these queries ...
http://autobuild.buildroot.net/?reason=uboot-tools-2018.03
http://autobuild.buildroot.net/?reason=uboot-tools-2018.05

Upstream: pending

Signed-off-by: Matthew Weber <matthew.weber@rockwellcollins.com>
2018-09-10 20:20:34 -04:00
Tom Rini
168de20f3b Revert "fw_printenv: Don't bail out directly after one env read error"
As pointed out by Wolfgang Denk, the problem with this fix is that while
interactive users will see that we have found one part of the
environment failed and are using the other, progmatic use will not see
this and can lead to problems.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-07-01 22:10:33 -04:00
Joe Hershberger
3925b2ac97 fw_printenv: Don't bail out directly after one env read error
When using a redundant environment a read error should simply mean to
not use that copy instead of giving up completely. The other copy may
be just fine.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Ioan-Adrian Ratiu <adrian.ratiu@ni.com>
2018-06-27 13:09:16 -04:00
Shyam Saini
919d25c920 u-boot: Fix several typos
's/environemnt/environment/' and
	's/Environemnt/Environment/'

Signed-off-by: Shyam Saini <shyam@amarulasolutions.com>
2018-06-13 07:49:13 -04:00
Alex Kiernan
94b233f443 tools: env: Use getline rather than fgets when reading config/script
When reading the config file, or a script file, use getline rather than
fgets so line lengths aren't limited by the size of a compiled in buffer
(128 characters for config, 1024 for scripts).

Rename 'dump' to 'line' so it's clear we're working with a line of text.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
2018-06-13 07:49:12 -04:00
Tom Rini
83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00
Kristian Amlie
8a0b827b1a fw_printenv: Fix crash due to incorrect size for malloc'ed string.
Using sizeof gives the size of the pointer only, not the string. This
could easily lead to crashes when using -l argument.

Signed-off-by: Kristian Amlie <kristian.amlie@northern.tech>
2018-04-10 15:19:15 -04:00
Alex Kiernan
dbc3432379 tools: env: Implement atomic replace for filesystem
If the U-Boot environment is stored in a regular file and redundant
operation isn't set, then write to a temporary file and perform an
atomic rename.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
2018-03-19 16:14:19 -04:00
Alex Kiernan
899b5338fa tools: env: Refactor write path of flash_io()
Extract write path of flash_io() into a separate function. This patch
should be a functional no-op.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
Reviewed-by: Stefano Babic <sbabic@denx.de>
2018-03-19 16:14:19 -04:00
Alex Kiernan
2deb3cac08 tools: env: Fix CamelCasing style violation
Replace HaveRedundEnv with have_redund_env to fix style violation.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
2018-03-19 16:14:19 -04:00
Alex Kiernan
c7f52c4b6e tools: env: Pass through indent
Pass tools/env/fw_env.c through indent to correct style violations. This
commit consists of only one non-whitespace change:

  tools/env/fw_env.c:549: error: do not use assignment in if condition

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
2018-03-19 16:14:19 -04:00
Stefan Agner
cd655514aa tools/env: allow equal sign as key value separation
Treat the first equal sign as a key/value separation too. This makes
the script files compatible with mkenvimage input file format. It
won't support variables with equal signs anymore, but this seems not
really like a loss.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
2018-03-05 10:05:36 -05:00
Alex Kiernan
d877a6c50e Fix --noheader on fw_printenv
The single argument `--noheader' is expecting isn't taken from getopt
parsing, but instead from the remaining argv arguments.

Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
2018-02-14 12:14:15 -05:00
Jelle van der Waa
9e82087cef tools: remove unused ret
Remove unused ret from fw_env_flush.

Signed-off-by: Jelle van der Waa <jelle@vdwaa.nl>
Reviewed-by: Simon Glass <sjg@chromium.org>
2018-01-28 09:39:15 -05:00
S. Lockwood-Childs
34255b92e6 tools: env: Add support for direct read/write UBI volumes
Up to now we were able to read/write environment data from/to UBI
volumes only indirectly by gluebi driver. This driver creates NAND MTD
on top of UBI volumes, which is quite a workaroung for this use case.

Add support for direct read/write UBI volumes in order to not use
obsolete gluebi driver.

Forward-ported from this patch:
http://patchwork.ozlabs.org/patch/619305/

Original patch:
Signed-off-by: Marcin Niestroj <m.niestroj@grinn-global.com>

Forward port:
Signed-off-by: S. Lockwood-Childs <sjl@vctlabs.com>
2017-11-29 22:30:50 -05:00
Tom Rini
c6831c74a9 env: Remove CONFIG_ENV_AES support
This support has been deprecated since v2017.09 due to security issues.
We now remove this support.

Signed-off-by: Tom Rini <trini@konsulko.com>
2017-11-21 07:43:31 -05:00
Stefan Agner
84d46e7e89 tools: env: allow to print U-Boot version
The fw_env utility family has a default environment compiled in
which ties it quite strongly to the U-Boot source/config it has
been built with. Allow to display the U-Boot version it has been
built with using the -v/--version argument.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
Reviewed-by: Lukasz Majewski <lukma@denx.de>
2017-11-06 09:58:59 -05:00
Bin Meng
3b306c37cd tools: env: Add embedded.c to .gitignore
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
2017-10-16 09:42:51 -04:00
Simon Glass
84a42069f2 env: Add 'envtools' target to 'make help'
The target is not currently mentioned anywhere. Add it to the help so
people can find it.

Signed-off-by: Simon Glass <sjg@chromium.org>
2017-09-05 20:34:09 -04:00
Simon Glass
5733295714 env: Fix operation of 'make environ'
This was broken by the recent environment refactoring. Specifically:

$  make environ
scripts/Makefile.build:59: tools/environ/Makefile: No such file or directory
make[1]: *** No rule to make target 'tools/environ/Makefile'.  Stop.
make: *** [Makefile:1469: environ] Error 2

Fix this by updating the Makefile and adjusting the #include filesnames in
two C files.

Fixes: ec74f5f (Makefile: Rename 'env' target to 'environ')
Reported-by: Måns Rullgård <mans@mansr.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
2017-09-05 20:34:08 -04:00
Tom Rini
2d3229bea2 env: Fix out of tree building of tools-all
With the move of environment code from common/ to env/ a number of
changes needed to be made to various make targets.  We missed updating
some of the files required for out of tree builds of the tools.  Correct
the 'environ' target to know that we need to work under tools/env/ still
(not tools/environ/) and then update the wrappers in env_attr.c and
env_flags.c to point to the new correct file.

Reported-by: Peter Robinson <pbrobinson@gmail.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Tom Rini <trini@konsulko.com>
2017-09-05 15:59:47 -04:00
Lukasz Majewski
40fe89c6e8 fix: fw_env: Prevent writing error message on special files, which don't support fsync
According to fsync specification [1] some special files (e.g., a pipe, FIFO,
or socket) don't support synchronization and return either EROFS or EINVAL.

On the linux side the sys_fsync -> do_fsync() checks if the requested file
has f_op->fsync defined. If not it returns EINVAL [2].

This commit prevents writing error messages for files (devices), which
do not support fsync().

[1] - http://man7.org/linux/man-pages/man2/fsync.2.html
[2] - http://elixir.free-electrons.com/linux/v4.13-rc6/source/fs/sync.c#L183

Signed-off-by: Lukasz Majewski <lukma@denx.de>
Acked-by: Michael Heimpold <mhei@heimpold.de>
2017-09-03 15:30:31 -04:00
Simon Glass
382bee57f1 env: Rename setenv() to env_set()
We are now using an env_ prefix for environment functions. Rename setenv()
for consistency. Also add function comments in common.h.

Suggested-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Simon Glass <sjg@chromium.org>
2017-08-16 08:22:18 -04:00
Michael Heimpold
7e99e14d4b tools/fw_env: use fsync to ensure that data is physically stored
Closing a file descriptor does not guarantee that the data has been
successfully saved to disk, as the kernel might defer the write.

Signed-off-by: Michael Heimpold <mhei@heimpold.de>
2017-07-22 15:36:16 -04:00