04 Apr, 2014
1 commit
-
The Makefile is designed to use the host toolchain so it may be unsafe
to build the tests if the kernel has been configured and built for
another architecture. This fixes a build problem when the kernel has
been configured and built for the MIPS architecture but the host is not
MIPS (cross-compiled). The MIPS syscalls are only defined if one of the
following is true:1) _MIPS_SIM == _MIPS_SIM_ABI64
2) _MIPS_SIM == _MIPS_SIM_ABI32
3) _MIPS_SIM == _MIPS_SIM_NABI32Of course, none of these make sense on a non-MIPS toolchain and the
following build problem occurs when building on a non-MIPS host.linux/usr/include/linux/kexec.h:50: userspace cannot reference function or variable defined in the kernel
samples/seccomp/bpf-direct.c: In function `emulator':
samples/seccomp/bpf-direct.c:76:17: error: `__NR_write' undeclared (first use in this function)Signed-off-by: Markos Chandras
Reported-by: Paul Gortmaker
Cc: Ralf Baechle
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
04 Dec, 2013
1 commit
-
Previously, example_init() leaked a kset if any of the object creations
failed. This fixes the leak by calling kset_unregister() in the error
path.Signed-off-by: Bjorn Helgaas
Signed-off-by: Greg Kroah-Hartman
15 Nov, 2013
1 commit
-
This patch enhances the type safety for the kfifo API. It is now safe
to put const data into a non const FIFO and the API will now generate a
compiler warning when reading from the fifo where the destination
address is pointing to a const variable.As a side effect the kfifo_put() does now expect the value of an element
instead a pointer to the element. This was suggested Russell King. It
make the handling of the kfifo_put easier since there is no need to
create a helper variable for getting the address of a pointer or to pass
integers of different sizes.IMHO the API break is okay, since there are currently only six users of
kfifo_put().The code is also cleaner by kicking out the "if (0)" expressions.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stefani Seibold
Cc: Russell King
Cc: Hauke Mehrtens
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
07 Sep, 2013
1 commit
-
Pull Tile arch updates from Chris Metcalf:
"These changes bring in a bunch of new functionality that has been
maintained internally at Tilera over the last year, plus other stray
bits of work that I've taken into the tile tree from other folks.The changes include some PCI root complex work, interrupt-driven
console support, support for performing fast-path unaligned data
fixups by kernel-based JIT code generation, CONFIG_PREEMPT support,
vDSO support for gettimeofday(), a serial driver for the tilegx
on-chip UART, KGDB support, more optimized string routines, support
for ftrace and kprobes, improved ASLR, and many bug fixes.We also remove support for the old TILE64 chip, which is no longer
buildable"* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (85 commits)
tile: refresh tile defconfig files
tile: rework
tile PCI RC: make default consistent DMA mask 32-bit
tile: add null check for kzalloc in tile/kernel/setup.c
tile: make __write_once a synonym for __read_mostly
tile: remove support for TILE64
tile: use asm-generic/bitops/builtin-*.h
tile: eliminate no-op "noatomichash" boot argument
tile: use standard tile_bundle_bits type in traps.c
tile: simplify code referencing hypervisor API addresses
tile: change to in comments
tile: mark pcibios_init() as __init
tile: check for correct compiler earlier in asm-offsets.c
tile: use standard 'generic-y' model for
tile: use asm-generic version of
tile PCI RC: add comment about "PCI hole" problem
tile: remove DEBUG_EXTRA_FLAGS kernel config option
tile: add virt_to_kpte() API and clean up and document behavior
tile: support FRAME_POINTER
tile: support reporting Tilera hypervisor statistics
...
06 Sep, 2013
1 commit
-
…3.12/logitech', 'for-3.12/multitouch-win8', 'for-3.12/trasnport-driver-cleanup', 'for-3.12/uhid', 'for-3.12/upstream' and 'for-3.12/wiimote' into for-linus
04 Sep, 2013
1 commit
-
This extends the uhid example client. It properly documents the built-in
report-descriptor an adds explicit report-numbers.Furthermore, LED output reports are added to utilize the new UHID output
reports of the kernel. Support for 3 basic LEDs is added and a small
report-parser to print debug messages if output reports were received.To test this, simply write the EV_LED+LED_CAPSL+1 event to the evdev
device-node of the uhid-device and the kernel will forward it to your uhid
client.Signed-off-by: David Herrmann
Signed-off-by: Jiri Kosina
30 Aug, 2013
1 commit
-
This change includes support for Kprobes, Jprobes and Return Probes.
Reviewed-by: Masami Hiramatsu
Signed-off-by: Tony Lu
Signed-off-by: Chris Metcalf
20 Aug, 2013
1 commit
-
To fix:
# Untracked files:
# (use "git add ..." to include in what will be committed)
#
# samples/hidraw/hid-exampleas seen in git status output after an allyesconfig build.
Signed-off-by: Paul Gortmaker
Signed-off-by: Jiri Kosina
28 Mar, 2013
1 commit
-
Put a warning into sample hidraw code in samples/hidraw/hid-example.c
in case the userspace headers are missing the necessary defines and
need to be updated.Signed-off-by: Jiri Kosina
20 Feb, 2013
1 commit
-
Pull perf changes from Ingo Molnar:
"There are lots of improvements, the biggest changes are:Main kernel side changes:
- Improve uprobes performance by adding 'pre-filtering' support, by
Oleg Nesterov.- Make some POWER7 events available in sysfs, equivalent to what was
done on x86, from Sukadev Bhattiprolu.- tracing updates by Steve Rostedt - mostly misc fixes and smaller
improvements.- Use perf/event tracing to report PCI Express advanced errors, by
Tony Luck.- Enable northbridge performance counters on AMD family 15h, by Jacob
Shin.- This tracing commit:
tracing: Remove the extra 4 bytes of padding in events
changes the ABI. All involved parties (PowerTop in particular)
seem to agree that it's safe to do now with the introduction of
libtraceevent, but the devil is in the details ...Main tooling side changes:
- Add 'event group view', from Namyung Kim:
To use it, 'perf record' should group events when recording. And
then perf report parses the saved group relation from file header
and prints them together if --group option is provided. You can
use the 'perf evlist' command to see event group information:$ perf record -e '{ref-cycles,cycles}' noploop 1
[ perf record: Woken up 2 times to write data ]
[ perf record: Captured and wrote 0.385 MB perf.data (~16807 samples) ]$ perf evlist --group
{ref-cycles,cycles}With this example, default perf report will show you each event
separately.You can use --group option to enable event group view:
$ perf report --group
...
# group: {ref-cycles,cycles}
# ========
# Samples: 7K of event 'anon group { ref-cycles, cycles }'
# Event count (approx.): 6876107743
#
# Overhead Command Shared Object Symbol
# ................ ....... ................. ..........................
99.84% 99.76% noploop noploop [.] main
0.07% 0.00% noploop ld-2.15.so [.] strcmp
0.03% 0.00% noploop [kernel.kallsyms] [k] timerqueue_del
0.03% 0.03% noploop [kernel.kallsyms] [k] sched_clock_cpu
0.02% 0.00% noploop [kernel.kallsyms] [k] account_user_time
0.01% 0.00% noploop [kernel.kallsyms] [k] __alloc_pages_nodemask
0.00% 0.00% noploop [kernel.kallsyms] [k] native_write_msr_safe
0.00% 0.11% noploop [kernel.kallsyms] [k] _raw_spin_lock
0.00% 0.06% noploop [kernel.kallsyms] [k] find_get_page
0.00% 0.02% noploop [kernel.kallsyms] [k] rcu_check_callbacks
0.00% 0.02% noploop [kernel.kallsyms] [k] __current_kernel_timeAs you can see the Overhead column now contains both of ref-cycles
and cycles and header line shows group information also - 'anon
group { ref-cycles, cycles }'. The output is sorted by period of
group leader first.- Initial GTK+ annotate browser, from Namhyung Kim.
- Add option for runtime switching perf data file in perf report,
just press 's' and a menu with the valid files found in the current
directory will be presented, from Feng Tang.- Add support to display whole group data for raw columns, from Jiri
Olsa.- Add per processor socket count aggregation in perf stat, from
Stephane Eranian.- Add interval printing in 'perf stat', from Stephane Eranian.
- 'perf test' improvements
- Add support for wildcards in tracepoint system name, from Jiri
Olsa.- Add anonymous huge page recognition, from Joshua Zhu.
- perf build-id cache now can show DSOs present in a perf.data file
that are not in the cache, to integrate with build-id servers being
put in place by organizations such as Fedora.- perf top now shares more of the evsel config/creation routines with
'record', paving the way for further integration like 'top'
snapshots, etc.- perf top now supports DWARF callchains.
- Fix mmap limitations on 32-bit, fix from David Miller.
- 'perf bench numa mem' NUMA performance measurement suite
- ... and lots of fixes, performance improvements, cleanups and other
improvements I failed to list - see the shortlog and git log for
details."* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (270 commits)
perf/x86/amd: Enable northbridge performance counters on AMD family 15h
perf/hwbp: Fix cleanup in case of kzalloc failure
perf tools: Fix build with bison 2.3 and older.
perf tools: Limit unwind support to x86 archs
perf annotate: Make it to be able to skip unannotatable symbols
perf gtk/annotate: Fail early if it can't annotate
perf gtk/annotate: Show source lines with gray color
perf gtk/annotate: Support multiple event annotation
perf ui/gtk: Implement basic GTK2 annotation browser
perf annotate: Fix warning message on a missing vmlinux
perf buildid-cache: Add --update option
uprobes/perf: Avoid uprobe_apply() whenever possible
uprobes/perf: Teach trace_uprobe/perf code to use UPROBE_HANDLER_REMOVE
uprobes/perf: Teach trace_uprobe/perf code to pre-filter
uprobes/perf: Teach trace_uprobe/perf code to track the active perf_event's
uprobes: Introduce uprobe_apply()
perf: Introduce hw_perf_event->tp_target and ->tp_list
uprobes/perf: Always increment trace_uprobe->nhit
uprobes/tracing: Kill uprobe_trace_consumer, embed uprobe_consumer into trace_uprobe
uprobes/tracing: Introduce is_trace_uprobe_enabled()
...
05 Feb, 2013
1 commit
-
The seccomp filters are currently built for the build host, not for the
machine that they are going to run on, but they are also built for with
the -m32 flag if the kernel is built for a 32 bit machine, both of which
seems rather odd.It broke allyesconfig on my machine, which is x86-64, but building for
32 bit ARM, with this error message:In file included from /usr/include/stdio.h:28:0,
from samples/seccomp/bpf-fancy.c:15:
/usr/include/features.h:324:26: fatal error: bits/predefs.h: No such file or directorybecause there are no 32 bit libc headers installed on this machine. We
should really be building all the samples for the target machine rather
than the build host, but since the infrastructure for that appears to be
missing right now, let's be a little bit smarter and not pass the '-m32'
flag to the HOSTCC when cross- compiling.Signed-off-by: Arnd Bergmann
Acked-by: Kees Cook
Cc: Heiko Carstens
Cc: James Morris
Acked-by: Will Drewry
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
26 Jan, 2013
1 commit
-
The tracepoint sample code was used to teach developers how to
create their own tracepoints. But now the trace_events have been
added as a higher level that is used directly by developers today.Only the trace_event code should use the tracepoint interface
directly and no new tracepoints should be added.Besides, the example had a race condition with the use of the
->d_name.name dentry field, as pointed out by Al Viro.Best just to remove the code so it wont be used by other developers.
Link: http://lkml.kernel.org/r/20130123225523.GY4939@ZenIV.linux.org.uk
Cc: Al Viro
Acked-by: Mathieu Desnoyers
Signed-off-by: Steven Rostedt
04 Jan, 2013
1 commit
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CONFIG_HOTPLUG is going away as an option. As a result, the __dev*
markings need to be removed.This change removes the last of the __dev* markings from the kernel from
a variety of different, tiny, places.Based on patches originally written by Bill Pemberton, but redone by me
in order to handle some of the coding style issues better, by hand.Cc: Bill Pemberton
Signed-off-by: Greg Kroah-Hartman
12 Sep, 2012
1 commit
-
On s390 the flag to force 31 builds is -m31 instead of -m32 unlike
on all (?) other architectures.Fixes this compile error:
HOSTCC samples/seccomp/bpf-direct.o
cc1: error: unrecognized command line option "-m32"
make[2]: *** [samples/seccomp/bpf-direct.o] Error 1Signed-off-by: Heiko Carstens
Acked-by: Kees Cook
Signed-off-by: James Morris
17 Aug, 2012
1 commit
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Linux 3.6-rc2
Resync with Linus.
03 Aug, 2012
1 commit
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The LO_ARG define needs to consider endianness also for 32 bit builds.
The "bpf_fancy" test case didn't work on s390 in 32 bit and compat mode
because the LO_ARG define resulted in a BPF program which read the upper
halve of the 64 bit system call arguments instead of the lower halves.Signed-off-by: Heiko Carstens
Acked-by: Kees Cook
Signed-off-by: James Morris
25 Jul, 2012
1 commit
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Pull HID updates from Jiri Kosina:
"The list of changes worth pointing out explicitly:- We are getting 'UHID', which is a new framework for implementing HID
transport drivers in userspace (this is different from HIDRAW, which
is transport-independent and provides report parsing facilities;
uhid is for the other (transport) part of the pipeline).It's needed for (and currently being used by) Bluetooth-LowEnergy,
as its specification mandates things we don't want in the kernel.Written by David Herrmann.
- there have been quite a few bugs in runtime suspend/resume paths
(probably never reported to actually happen in the wild, but still).
Alan Stern fixed those.- a few other driver updates and fixes and random new device support."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (45 commits)
HID: add ASUS AIO keyboard model AK1D
HID: add support for Cypress barcode scanner 04B4:ED81
HID: Allow drivers to be their own listener
HID: usbhid: fix error paths in suspend
HID: usbhid: check for suspend or reset before restarting
HID: usbhid: replace HID_REPORTED_IDLE with HID_SUSPENDED
HID: usbhid: inline some simple routines
HID: usbhid: fix autosuspend calls
HID: usbhid: fix use-after-free bug
HID: hid-core: optimize in case of hidraw
HID: hidraw: fix list->buffer memleak
HID: uhid: Fix sending events with invalid data
HID: roccat: added sensor sysfs attribute for Savu
HID: Add driver for Holtek based keyboards with broken HID
HID: Add suport for the brightness control keys on HP keyboards
HID: magicmouse: Implement Multi-touch Protocol B (MT-B)
HID: magicmouse: Removing report_touches switch
HID: roccat: rename roccat_common functions to roccat_common2
HID: roccat: fix wrong hid_err usage on struct usb_device
HID: roccat: move functionality to roccat-common
...
28 Jun, 2012
1 commit
-
git status should be clean following make allmodconfig && make. Add
a .gitignore file to the samples/seccomp directory to ignore binaries
produced there.Signed-off-by: Chad Williamson
Reviewed-By: Will Drewry
Acked-by: Kees Cook
Signed-off-by: James Morris
18 Jun, 2012
1 commit
-
This adds an example user-space program that emulates a 3 button mouse
with wheel. It detects keyboard presses and moves the mouse accordingly.It register a fake HID device to feed the raw HID reports into the kernel.
In this example, you could use uinput to get the same result, but this
shows how to get the same behavior with uhid so you don't need HID parsers
in user-space.Signed-off-by: David Herrmann
Signed-off-by: Jiri Kosina
19 Apr, 2012
1 commit
-
This change fixes the compilation error triggered here for
i386 allmodconfig in linux-next:
http://kisskb.ellerman.id.au/kisskb/buildresult/6123842/Logic attempting to predict the host architecture has been
removed from the Makefile. Instead, the bpf-direct sample
should now compile on any architecture, but if the architecture
is not supported, it will compile a minimal main() function.This change also ensures the samples are not compiled when
there is no seccomp filter support.(Note, I wasn't able to reproduce the error locally, but
the existing approach was clearly flawed. This tweak
should resolve your issue and avoid other future weirdness.)Reported-by: Paul Gortmaker
Suggested-by: Kees Cook
Signed-off-by: Will Drewry
Signed-off-by: James Morris
14 Apr, 2012
1 commit
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Documents how system call filtering using Berkeley Packet
Filter programs works and how it may be used.
Includes an example for x86 and a semi-generic
example using a macro-based code generator.Acked-by: Eric Paris
Signed-off-by: Will Drewry
Acked-by: Kees Cookv18: - added acked by
- update no new privs numbers
v17: - remove @compat note and add Pitfalls section for arch checking
(keescook@chromium.org)
v16: -
v15: -
v14: - rebase/nochanges
v13: - rebase on to 88ebdda6159ffc15699f204c33feb3e431bf9bdc
v12: - comment on the ptrace_event use
- update arch support comment
- note the behavior of SECCOMP_RET_DATA when there are multiple filters
(keescook@chromium.org)
- lots of samples/ clean up incl 64-bit bpf-direct support
(markus@chromium.org)
- rebase to linux-next
v11: - overhaul return value language, updates (keescook@chromium.org)
- comment on do_exit(SIGSYS)
v10: - update for SIGSYS
- update for new seccomp_data layout
- update for ptrace option use
v9: - updated bpf-direct.c for SIGILL
v8: - add PR_SET_NO_NEW_PRIVS to the samples.
v7: - updated for all the new stuff in v7: TRAP, TRACE
- only talk about PR_SET_SECCOMP now
- fixed bad JLE32 check (coreyb@linux.vnet.ibm.com)
- adds dropper.c: a simple system call disabler
v6: - tweak the language to note the requirement of
PR_SET_NO_NEW_PRIVS being called prior to use. (luto@mit.edu)
v5: - update sample to use system call arguments
- adds a "fancy" example using a macro-based generator
- cleaned up bpf in the sample
- update docs to mention arguments
- fix prctl value (eparis@redhat.com)
- language cleanup (rdunlap@xenotime.net)
v4: - update for no_new_privs use
- minor tweaks
v3: - call out BPF Berkeley Packet Filter (rdunlap@xenotime.net)
- document use of tentative always-unprivileged
- guard sample compilation for i386 and x86_64
v2: - move code to samples (corbet@lwn.net)
Signed-off-by: James Morris
09 Feb, 2012
1 commit
-
Add an rpmsg driver sample, which demonstrates how to communicate with
an AMP-configured remote processor over the rpmsg bus.Note how once probed, the driver can immediately start sending messages
using the rpmsg_send() API, without having to worry about creating endpoints
or allocating rpmsg addresses: all that work is done by the rpmsg bus,
and the required information is already embedded in the rpmsg channel
that the driver is probed with.In this sample, the driver simply sends a "Hello World!" message to the remote
processor repeatedly.Designed with Brian Swetland .
Signed-off-by: Ohad Ben-Cohen
Cc: Brian Swetland
Cc: Arnd Bergmann
Cc: Grant Likely
Cc: Tony Lindgren
Cc: Russell King
Cc: Rusty Russell
Cc: Andrew Morton
Cc: Greg KH
Cc: Stephen Boyd
01 Nov, 2011
1 commit
-
Signed-off-by: Paul Bolle
Signed-off-by: Michal Marek
01 Jul, 2011
2 commits
-
The perf_event overflow handler does not receive any caller-derived
argument, so many callers need to resort to looking up the perf_event
in their local data structure. This is ugly and doesn't scale if a
single callback services many perf_events.Fix by adding a context parameter to perf_event_create_kernel_counter()
(and derived hardware breakpoints APIs) and storing it in the perf_event.
The field can be accessed from the callback as event->overflow_handler_context.
All callers are updated.Signed-off-by: Avi Kivity
Signed-off-by: Peter Zijlstra
Link: http://lkml.kernel.org/r/1309362157-6596-2-git-send-email-avi@redhat.com
Signed-off-by: Ingo Molnar -
The nmi parameter indicated if we could do wakeups from the current
context, if not, we would set some state and self-IPI and let the
resulting interrupt do the wakeup.For the various event classes:
- hardware: nmi=0; PMI is in fact an NMI or we run irq_work_run from
the PMI-tail (ARM etc.)
- tracepoint: nmi=0; since tracepoint could be from NMI context.
- software: nmi=[0,1]; some, like the schedule thing cannot
perform wakeups, and hence need 0.As one can see, there is very little nmi=1 usage, and the down-side of
not using it is that on some platforms some software events can have a
jiffy delay in wakeup (when arch_irq_work_raise isn't implemented).The up-side however is that we can remove the nmi parameter and save a
bunch of conditionals in fast paths.Signed-off-by: Peter Zijlstra
Cc: Michael Cree
Cc: Will Deacon
Cc: Deng-Cheng Zhu
Cc: Anton Blanchard
Cc: Eric B Munson
Cc: Heiko Carstens
Cc: Paul Mundt
Cc: David S. Miller
Cc: Frederic Weisbecker
Cc: Jason Wessel
Cc: Don Zickus
Link: http://lkml.kernel.org/n/tip-agjev8eu666tvknpb3iaj0fg@git.kernel.org
Signed-off-by: Ingo Molnar
23 May, 2011
1 commit
21 Apr, 2011
1 commit
-
samples/hid-example.o needs some Kconfig and Makefile additions in order
to build. It should use headers from the build tree, so use
HEADERS_CHECK to require that those header files be present.Change the kconfig symbol from tristate to bool since userspace cannot be
built as loadable modules.However, I don't understand why the userspace header files are not present
as reported in Andrew's build log, since it builds OK on x86_64 without
any of these changes.Signed-off-by: Randy Dunlap
Cc: Alan Ott
Cc: Jiri Kosina
Signed-off-by: Andrew Morton
Signed-off-by: Jiri Kosina
09 Apr, 2011
1 commit
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On systems where userspace doesn't have new hidraw.h populated to
/usr/include, the hidraw sample won't compile as it's missing the new
ioctl defitions.Introduce temporary ugly workaround to define the ioctls "manually"
in such cases, just to avoid miscompilation in allmodconfig cases.Reported-by: Stephen Rothwell
Signed-off-by: Jiri Kosina
31 Mar, 2011
1 commit
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Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: Lucas De Marchi
22 Mar, 2011
1 commit
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Documenation for the hidraw driver, with sample program.
Signed-off-by: Alan Ott
Signed-off-by: Jiri Kosina
30 Oct, 2010
1 commit
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Add an example of how to add a dynamic kdb shell command via a kernel
module.Signed-off-by: Jason Wessel
23 Oct, 2010
1 commit
-
* 'llseek' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/bkl:
vfs: make no_llseek the default
vfs: don't use BKL in default_llseek
llseek: automatically add .llseek fop
libfs: use generic_file_llseek for simple_attr
mac80211: disallow seeks in minstrel debug code
lirc: make chardev nonseekable
viotape: use noop_llseek
raw: use explicit llseek file operations
ibmasmfs: use generic_file_llseek
spufs: use llseek in all file operations
arm/omap: use generic_file_llseek in iommu_debug
lkdtm: use generic_file_llseek in debugfs
net/wireless: use generic_file_llseek in debugfs
drm: use noop_llseek
15 Oct, 2010
1 commit
-
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====Signed-off-by: Arnd Bergmann
Cc: Julia Lawall
Cc: Christoph Hellwig
02 Oct, 2010
1 commit
-
The kfifo_dma family of functions use sg_mark_end() on the last element in
their scatterlist. This forces use of a fresh scatterlist for each DMA
operation, which makes recycling a single scatterlist impossible.Change the behavior of the kfifo_dma functions to match the usage of the
dma_map_sg function. This means that users must respect the returned
nents value. The sample code is updated to reflect the change.This bug is trivial to cause: call kfifo_dma_in_prepare() such that it
prepares a scatterlist with a single entry comprising the whole fifo.
This is the case when you map the entirety of a newly created empty fifo.
This causes the setup_sgl() function to mark the first scatterlist entry
as the end of the chain, no matter what comes after it.Afterwards, add and remove some data from the fifo such that another call
to kfifo_dma_in_prepare() will create two scatterlist entries. It returns
nents=2. However, due to the previous sg_mark_end() call, sg_is_last()
will now return true for the first scatterlist element. This causes the
sample code to print a single scatterlist element when it should print
two.By removing the call to sg_mark_end(), we make the API as similar as
possible to the DMA mapping API. All users are required to respect the
returned nents.Signed-off-by: Ira W. Snyder
Cc: Stefani Seibold
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
21 Aug, 2010
5 commits
-
Provide a check in all the kfifo examples to validate the correct
execution of each testcase.Signed-off-by: Andrea Righi
Acked-by: Stefani Seibold
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
We use a dynamically allocated kfifo in the dma example, so we need to
free it when unloading the module.Signed-off-by: Andrea Righi
Acked-by: Stefani Seibold
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The scatterlist is used uninitialized in kfifo_dma_in_prepare(). This
triggers the following bug if CONFIG_DEBUG_SG=y:------------[ cut here ]------------
kernel BUG at include/linux/scatterlist.h:65!
invalid opcode: 0000 [#1] PREEMPT SMP
...
Call Trace:
[] setup_sgl+0x6b/0xe0
[] ? example_init+0x0/0x265 [dma_example]
[] __kfifo_dma_in_prepare+0x21/0x30
[] example_init+0x124/0x265 [dma_example]
[] ? trace_module_notify+0x25/0x370
[] ? free_pages_prepare+0x11e/0x1e0
[] ? get_parent_ip+0x11/0x50
[] ? trace_module_notify+0x25/0x370
[] ? trace_hardirqs_on+0xd/0x10
[] ? mutex_unlock+0xe/0x10
[] ? trace_module_notify+0x41/0x370
[] ? __blocking_notifier_call_chain+0x45/0x80
[] ? vfree+0x2a/0x30
[] ? up_read+0x23/0x40
[] ? __blocking_notifier_call_chain+0x65/0x80
[] do_one_initcall+0x43/0x180
[] sys_init_module+0xba/0x200
[] system_call_fastpath+0x16/0x1b
RIP [] setup_sgl_buf+0x1a1/0x1b0
RSP
---[ end trace a72b979fd3c1d3a5 ]---Add the proper initialization to avoid the bug.
Signed-off-by: Andrea Righi
Acked-by: Stefani Seibold
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Provide a static array of expected items that kfifo should contain at the
end of the test to validate it.Signed-off-by: Andrea Righi
Cc: Stefani Seibold
Cc: Greg KH
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Add a testcase for kfifo_skip() to the byte stream fifo example.
Signed-off-by: Andrea Righi
Cc: Greg KH
Acked-by: Stefani Seibold
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Aug, 2010
1 commit
-
Add four examples to the kernel sample directory.
It shows how to handle:
- a byte stream fifo
- a integer type fifo
- a dynamic record sized fifo
- the fifo DMA functions[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Stefani Seibold
Cc: Greg KH
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds