Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:
@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)
@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@
- RAND = get_random_u32();
... when != RAND
- RAND %= (E);
+ RAND = prandom_u32_max(E);
// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@
((T)get_random_u32()@p & (LITERAL))
// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@
value = None
if literal.startswith('0x'):
value = int(literal, 16)
elif literal[0] in '123456789':
value = int(literal, 10)
if value is None:
print("I don't know how to handle %s" % (literal))
cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
print("Skipping 0x%x for cleanup elsewhere" % (value))
cocci.include_match(False)
elif value & (value + 1) != 0:
print("Skipping 0x%x because it's not a power of two minus one" % (value))
cocci.include_match(False)
elif literal.startswith('0x'):
coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))
// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@
- (FUNC()@p & (LITERAL))
+ prandom_u32_max(RESULT)
@collapse_ret@
type T;
identifier VAR;
expression E;
@@
{
- T VAR;
- VAR = (E);
- return VAR;
+ return E;
}
@drop_var@
type T;
identifier VAR;
@@
{
- T VAR;
... when != VAR
}
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 1334 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Emulate random power cuts by switching device to ro after a number of
writes to allow simple power cut testing with nand-sim.
Maximum and minimum number of successful writes before power cut and
what kind of writes (EC header, VID header or none) to interrupt
configurable via debugfs.
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>
Signed-off-by: Richard Weinberger <richard@nod.at>
If fm_debug is set fastmap debugging is enabled by default.
This is useful if one wants to debug fastmap on an UBI device
with serves the rootfs.
The the UBI attach mechanism runs long before debugfs can be mounted
and chk_fastmap set.
Signed-off-by: Richard Weinberger <richard@nod.at>
Using this debugfs knob fastmap self checks can be controlled.
Signed-off-by: Richard Weinberger <richard@nod.at>
Reviewed-by: Tanya Brokhman <tlinder@codeaurora.org>
Use more preferable function name which implies using a pseudo-random
number generator.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
ubi_debug_info struct was dynamically allocated which
is always suboptimal, for it tends to fragment memory
and make the code error-prone.
Fix this by embedding it in ubi_device struct.
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
With this patch code is a bit more readable and there's no
generated code or functionality impact.
Furthermore, this abstracts implementation details and
will allow to change ubi_debug_info in a less invasive way.
Signed-off-by: Ezequiel Garcia <elezegarcia@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
UBI currently prints a lot of information when it mounts a volume, which
bothers some people. Make it less chatty - print only important information
by default.
Get rid of 'dbg_msg()' macro completely.
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
After re-naming the 'struct ubi_scan_volume' we should adjust all variables
named 'sv' to something else, because 'sv' stands for "scanning volume".
Let's rename it to 'av' which stands for "attaching volume" which is
a bit more consistent and has the same length, which makes re-naming easy.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
After re-naming the 'struct ubi_scan_leb' we should adjust all variables
named 'seb' to something else, because 'seb' stands for "scanning eraseblock".
Let's rename it to 'aeb' which stands for "attaching eraseblock" which is
a bit more consistend and has the same length.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Rename 'struct ubi_scan_volume' to 'struct ubi_ainf_volume'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word and use "ainf" instead which stands
for "attach information". It has the same length as "scan" so re-naming
is trivial.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Rename 'struct ubi_scan_leb' to 'struct ubi_ainf_leb'. This is part
of the code re-structuring I am trying to do in order to add fastmap
in a more logical way. Fastmap can share a lot with scanning, including
the attach-time data structures, which all now have "scan" word in the
name. Let's get rid of this word and use "ainf" instead which stands
for "attach information". It has the same length as "scan" so re-naming
is trivial.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
This patch removes the 'dbg_err()' macro and we now use 'ubi_err' instead.
The idea of 'dbg_err()' was to compile out some error message to make the
binary a bit smaller - but I think it was a bad idea.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
This patch kills the UBI debugging Kconfig option completely and makes all the
debugging stuff to be always compiled-in. It was pain in the neck to maintain
this useless option because all users I am aware of have debugging enabled
anyway - how else will you diagnose errors otherwise?
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_mkvol_req()' to 'ubi_dump_mkvol_req()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_seb()' to 'ubi_dump_seb()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_sv()' to 'ubi_dump_sv()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_vtbl_record()' to 'ubi_dump_vtbl_record()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
I am going to remove the "UBI debugging" compilation option and make the
debugging stuff to be always compiled it. This patch is a preparation
which renames 'ubi_dbg_dump_vol_info()' to 'ubi_dump_vol_info()'.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.
Always dump the VID and EC headers' contents in case of errors when it
is helpful.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.
Always dump the flash contents in case of errors, not only when debugging is
enabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
UBI (and UBIFS) are a bit over-engineered WRT debugging. The idea was to
link as few as possible when debugging is disabled, but the downside is
that most people produce bug reports which are difficult to understand.
This patch weeds out the 'ubi_dbg_dump_stack()' function and turns it
into 'dump_stack()' - it is always useful to have stack dump in case of
an error.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@linux.intel.com>
Patch ab50ff6847 broke UBI debugging messages:
before that commit when UBI debugging was enabled, users saw few useful
debugging messages after attaching an MTD device. However, that patch turned
'dbg_msg()' into 'pr_debug()', so to enable the debugging messages users have
to enable them first via /sys/kernel/debug/dynamic_debug/control, which is
very impractical.
This commit makes 'dbg_msg()' to use 'printk()' instead of 'pr_debug()', just
as it was before the breakage.
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: stable@kernel.org [3.0+]
Michal Marek spotted the same issue in UBIFS and this patch fixes UBI,
see "UBIFS: not build debug messages with CONFIG_UBIFS_FS_DEBUG disabled"
When UBI debugging is disabled, we have debugging messages defined as:
if (0)
pr_debug()
But pr_debug macro defines data structures with debugging data and makes
the linux binary larger, even though we have "if (0)".
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@intel.com>
Kill the UBI 'debug_tsts' module parameter and switch to debugfs. Create
per-test mode files there. E.g., to enable bit-flips emulation you may just do:
echo 1 > /sys/kernel/debug/ubi/ubi0/tst_emulate_bitflips
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Current layout does not allow us to add inline functions to debug.h which use
the 'struct ubi_device' object, because it is undefined there. Move
'#include "debug.h"' in "ubi.h" down so to make 'struct ubi_device" be defined.
Additionally, this makes it possible to remove a bunch of forward declarations
in "debug.h". This is a preparation to the next patch.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
We'll need the 'struct ubi_device *ubi' pointer in every debugging function (to
access the ->dbg field), so add this pointer to all the functions implementing
UBI debugging test modes like 'ubi_dbg_is_bitflip()' etc.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch introduces debugfs support to UBI. All the UBI stuff is kept in the
"ubi" debugfs directory, which contains per-UBI device "ubi/ubiX"
sub-directories, containing debugging files. This file also creates
"ubi/ubiX/chk_gen" and "ubi/ubiX/chk_io" knobs for switching general and I/O
extra checks on and off. And it removes the 'debug_chks' UBI module parameters.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Remove custom dynamic prints and the module parameter to toggle them and use
the generic kernel dynamic printk infrastructure.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Similarly as we have done for UBIFS in
1dcffad741, turn the debugging macros into static
inline functions, for the same reasons: to avoid gcc 4.5 warnings.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
When debugging is disabled, define debugging prints as if (0) printk() to make
sure that the compiler still the format string in debugging messages even if
debugging is disabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Similarly to the debugging checks and message, make the test modes
be dynamically selected via the "debug_tsts" module parameter or
via the "/sys/module/ubi/parameters/debug_tsts" sysfs file. This
is consistent with UBIFS as well.
And now, since all the Kconfig knobs became dynamic, we can remove
the Kconfig.debug file completely.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch adds a possibility to dynamically switch UBI self-checks
on and off, instead of toggling them compile-time from the configuration
menu. This is much more flexible, and consistent with UBIFS, and this
also simplifies UBI Kconfig menu and the code.
This patch introduces two levels of self-checks - general, which
includes all self-checks which are relatively fast, and I/O, which
includes write-verify checks and erase-verify checks, which are
relatively slow and involve flash I/O.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch adds a possibility to dynamically select UBI debugging
messages, instead of selecting them compile-time from the configuration
menu. This is much more flexible, and consistent with UBIFS, and this
also simplifies UBI Kconfig menu and the code.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This additional little macro is used to print a bit more messages
while scanning the media. However, we have the 'dbg_bld()' macro
for this, so we better us 'dbg_bld()' and kill UBI_IO_DEBUG. This
simplifies the code a tiny bit.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Introduce a helper function to print hexdump: 'ubi_dbg_print_hex_dump()'.
It is compiled out if debugging is enabled. Will be used in the next patch.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Add an extra debugging check function which validates writes.
After every write it reads the data back, compares it with the
original data, and complains if they mismatch.
Useful for debugging. No-op if extra debugging checks are disabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Useful for debugging problems, compiled in only if UBI debugging
is enabled. This patch also makes the UBI writing function dump
the flash if it fails to write.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
The 'paranoid_check_empty()' is bogus because, which is easilly
seen on NOR flash, which has long erase cycles, and which may
easilly end-up with half-erased eraseblocks. In this case the
paranoid check fails. I is just wrong to assume that PEBs which
do not have EC headers always contain all 0xFF. Such assumption
should not be made on the I/O level, which is quite low.
Thus, just kill the check.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
This patch adds code which makes sure eraseblocks contain all 0xFF
bytes before starting using them. The verification is done only when
debugging checks are enabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Hch asked not to use "unit" for sub-systems, let it be so.
Also some other commentaries modifications.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Make I/O function to be always verbose when about CRC errors
and magic number errors when I/O debugging is enabled.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Jason A. Donenfeld