Previous patch removed can_priv::ctrlmode_static to replace it with
can_get_static_ctrlmode().
A condition sine qua non for this to work is that the controller
static modes should never be set in can_priv::ctrlmode_supported
(c.f. the comment on can_priv::ctrlmode_supported which states that it
is for "options that can be *modified* by netlink"). Also, this
condition is already correctly fulfilled by all existing drivers
which rely on the ctrlmode_static feature.
Nonetheless, we added an extra safeguard in can_set_static_ctrlmode()
to return an error value and to warn the developer who would be
adventurous enough to set to static a given feature that is already
set to supported.
The drivers which rely on the static controller mode are then updated
to check the return value of can_set_static_ctrlmode().
Link: https://lore.kernel.org/all/20211213160226.56219-3-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The statically enabled features of a CAN controller can be retrieved
using below formula:
| u32 ctrlmode_static = priv->ctrlmode & ~priv->ctrlmode_supported;
As such, there is no need to store this information. This patch remove
the field ctrlmode_static of struct can_priv and provides, in
replacement, the inline function can_get_static_ctrlmode() which
returns the same value.
Link: https://lore.kernel.org/all/20211213160226.56219-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The actual payload length of the CAN Remote Transmission Request (RTR)
frames is always 0, i.e. no payload is transmitted on the wire.
However, those RTR frames still use the DLC to indicate the length of
the requested frame.
As such, net_device_stats::tx_bytes should not be increased when
sending RTR frames.
The function can_get_echo_skb() already returns the correct length,
even for RTR frames (c.f. [1]). However, for historical reasons, the
drivers do not use can_get_echo_skb()'s return value and instead, most
of them store a temporary length (or dlc) in some local structure or
array. Using the return value of can_get_echo_skb() solves the
issue. After doing this, such length/dlc fields become unused and so
this patch does the adequate cleaning when needed.
This patch fixes all the CAN drivers.
Finally, can_get_echo_skb() is decorated with the __must_check
attribute in order to force future drivers to correctly use its return
value (else the compiler would emit a warning).
[1] commit ed3320cec2 ("can: dev: __can_get_echo_skb():
fix real payload length return value for RTR frames")
Link: https://lore.kernel.org/all/20211207121531.42941-6-mailhol.vincent@wanadoo.fr
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Yasushi SHOJI <yashi@spacecubics.com>
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Stephane Grosjean <s.grosjean@peak-system.com>
Cc: Andreas Larsson <andreas@gaisler.com>
Tested-by: Jimmy Assarsson <extja@kvaser.com> # kvaser
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
Tested-by: Stefan Mätje <stefan.maetje@esd.eu> # esd_usb2
[mkl: add conversion for grcan]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In [1], we introduced a set of units in linux/can/bittiming.h. Since
then, generic SI prefixes were added to linux/units.h in [2]. Those
new prefixes can perfectly replace CAN specific ones.
This patch replaces all occurrences of the CAN units with their
corresponding prefix (from linux/units) and the unit (as a comment)
according to below table.
CAN units SI metric prefix (from linux/units) + unit (as a comment)
------------------------------------------------------------------------
CAN_KBPS KILO /* BPS */
CAN_MBPS MEGA /* BPS */
CAM_MHZ MEGA /* Hz */
The definition are then removed from linux/can/bittiming.h
[1] commit 1d7750760b ("can: bittiming: add CAN_KBPS, CAN_MBPS and
CAN_MHZ macros")
[2] commit 26471d4a6c ("units: Add SI metric prefix definitions")
Link: https://lore.kernel.org/all/20211124014536.782550-1-mailhol.vincent@wanadoo.fr
Suggested-by: Jimmy Assarsson <extja@kvaser.com>
Suggested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
struct can_tdc::tdco represents the absolute offset from TDCV. Some
controllers use instead an offset relative to the Sample Point (SP)
such that:
| SSP = TDCV + absolute TDCO
| = TDCV + SP + relative TDCO
Consequently:
| relative TDCO = absolute TDCO - SP
The function can_tdc_get_relative_tdco() allow to retrieve this
relative TDCO value.
Link: https://lore.kernel.org/all/20210918095637.20108-7-mailhol.vincent@wanadoo.fr
CC: Stefan Mätje <Stefan.Maetje@esd.eu>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Some CAN device can measure the TDCV (Transmission Delay Compensation
Value) automatically for each transmitted CAN frames.
A callback function do_get_auto_tdcv() is added to retrieve that
value. This function is used only if CAN_CTRLMODE_TDC_AUTO is enabled
(if CAN_CTRLMODE_TDC_MANUAL is selected, the TDCV value is provided by
the user).
If the device does not support reporting of TDCV, do_get_auto_tdcv()
should be set to NULL and TDCV will not be reported by the netlink
interface.
On success, do_get_auto_tdcv() shall return 0. If the value can not be
measured by the device, for example because network is down or because
no frames were transmitted yet, can_priv::do_get_auto_tdcv() shall
return a negative error code (e.g. -EINVAL) to signify that the value
is not yet available. In such cases, TDCV is not reported by the
netlink interface.
Link: https://lore.kernel.org/all/20210918095637.20108-6-mailhol.vincent@wanadoo.fr
CC: Stefan Mätje <stefan.maetje@esd.eu>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The function can_calc_tdco() directly retrieves can_priv from the
net_device and directly modifies it.
This is annoying for the upcoming patch. In
drivers/net/can/dev/netlink.c:can_changelink(), the data bittiming are
written to a temporary structure and memcpyed to can_priv only after
everything succeeded. In the next patch, where we will introduce the
netlink interface for TDC parameters, we will add a new TDC block
which can potentially fail. For this reason, the data bittiming
temporary structure has to be copied after that to-be-introduced TDC
block. However, TDC also needs to access data bittiming information.
We change the prototype so that the data bittiming structure is passed
to can_calc_tdco() as an argument instead of retrieving it from
priv. This way can_calc_tdco() can access the data bittiming before it
gets memcpyed to priv.
Link: https://lore.kernel.org/all/20210918095637.20108-4-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In the current implementation, all Transmission Delay Compensation
(TDC) parameters are expressed in time quantum. However, ISO 11898-1
actually specifies that these should be expressed in *minimum* time
quantum.
Furthermore, the minimum time quantum is specified to be "one node
clock period long" (c.f. paragraph 11.3.1.1 "Bit time"). For sake of
simplicity, we prefer to use the "clock period" term instead of
"minimum time quantum" because we believe that it is more broadly
understood.
This patch fixes that discrepancy by updating the documentation and
the formula for TDCO calculation.
N.B. In can_calc_tdco(), the sample point (in time quantum) was
calculated using a division, thus introducing a risk of rounding and
truncation errors. On top of changing the unit to clock period, we
also modified the formula to use only additions.
Link: https://lore.kernel.org/all/20210918095637.20108-3-mailhol.vincent@wanadoo.fr
Suggested-by: Stefan Mätje <Stefan.Maetje@esd.eu>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
ISO 11898-1 specifies in section 11.3.3 "Transmitter delay
compensation" that "the configuration range for [the] SSP position
shall be at least 0 to 63 minimum time quanta."
Because SSP = TDCV + TDCO, it means that we should allow both TDCV and
TDCO to hold zero value in order to honor SSP's minimum possible
value.
However, current implementation assigned special meaning to TDCV and
TDCO's zero values:
* TDCV = 0 -> TDCV is automatically measured by the transceiver.
* TDCO = 0 -> TDC is off.
In order to allow for those values to really be zero and to maintain
current features, we introduce two new flags:
* CAN_CTRLMODE_TDC_AUTO indicates that the controller support
automatic measurement of TDCV.
* CAN_CTRLMODE_TDC_MANUAL indicates that the controller support
manual configuration of TDCV. N.B.: current implementation failed
to provide an option for the driver to indicate that only manual
mode was supported.
TDC is disabled if both CAN_CTRLMODE_TDC_AUTO and
CAN_CTRLMODE_TDC_MANUAL flags are off, c.f. the helper function
can_tdc_is_enabled() which is also introduced in this patch.
Also, this patch adds three fields: tdcv_min, tdco_min and tdcf_min to
struct can_tdc_const. While we are not convinced that those three
fields could be anything else than zero, we can imagine that some
controllers might specify a lower bound on these. Thus, those minimums
are really added "just in case".
Comments of struct can_tdc and can_tdc_const are updated accordingly.
Finally, the changes are applied to the etas_es58x driver.
Link: https://lore.kernel.org/all/20210918095637.20108-2-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
For CAN buses to work, a termination resistor has to be present at both
ends of the bus. This resistor is usually 120 Ohms, other values may be
required for special bus topologies.
This patch adds support for a generic GPIO based CAN termination. The
resistor value has to be specified via device tree, and it can only be
attached to or detached from the bus. By default the termination is not
active.
Link: https://lore.kernel.org/r/20210818071232.20585-4-o.rempel@pengutronix.de
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch fixes a typo in the documentation for struct can_tdc::tdcv.
The number "0" refers to automatic mode not the letter "O".
Further two grammar errors in the documentation for struct can_tdc are
fixed.
First grammar error: add a missing third person 's'.
Second grammar error: replace "such as" by "such that". The intent is
to give a condition, not an example.
Fixes: 289ea9e4ae ("can: add new CAN FD bittiming parameters: Transmitter Delay Compensation (TDC)")
Link: https://lore.kernel.org/r/20210616095922.2430415-1-mkl@pengutronix.de
Link: https://lore.kernel.org/r/20210616124057.60723-1-mailhol.vincent@wanadoo.fr
Co-developed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
After reading all CAN frames from the controller in the IRQ handler
and storing them into a skb_queue, the driver calls napi_schedule().
In the napi poll function the skb from the skb_queue are then pushed
into the networking stack.
However if napi_schedule() is called from a threaded IRQ handler this
triggers the following error:
| NOHZ tick-stop error: Non-RCU local softirq work is pending, handler #08!!!
To avoid this, create a new rx-offload
function (can_rx_offload_threaded_irq_finish()) with a call to
local_bh_disable()/local_bh_enable() around the napi_schedule() call.
Convert all drivers that call can_rx_offload_irq_finish() from
threaded IRQ context to can_rx_offload_threaded_irq_finish().
Link: https://lore.kernel.org/r/20210724204745.736053-4-mkl@pengutronix.de
Suggested-by: Daniel Glöckner <dg@emlix.com>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Instead of calling can_rx_offload_schedule() call napi_schedule()
directly. As this was the last use of can_rx_offload_schedule() remove
this helper function.
Link: https://lore.kernel.org/r/20210724204745.736053-3-mkl@pengutronix.de
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Adding a skb to the skb_queue in rx-offload requires to take a lock.
This commit avoids this by adding an unlocked skb queue that is
appended at the end of the ISR. Having one lock at the end of the ISR
should be OK as the HW is empty, not about to overflow.
Link: https://lore.kernel.org/r/20210724204745.736053-2-mkl@pengutronix.de
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Co-developed-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add three macro to simplify the readability of big bit timing numbers:
- CAN_KBPS: kilobits per second (one thousand)
- CAN_MBPS: megabits per second (one million)
- CAN_MHZ: megahertz per second (one million)
Example:
u32 bitrate_max = 8 * CAN_MBPS;
struct can_clock clock = {.freq = 80 * CAN_MHZ};
instead of:
u32 bitrate_max = 8000000;
struct can_clock clock = {.freq = 80000000};
Apply the new macro to driver/net/can/dev/bittiming.c.
Link: https://lore.kernel.org/r/20210306054040.76483-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The logic for the tdco calculation is to just reuse the normal sample
point: tdco = sp. Because the sample point is expressed in tenth of
percent and the tdco is expressed in time quanta, a conversion is
needed.
At the end,
ssp = tdcv + tdco
= tdcv + sp.
Another popular method is to set tdco to the middle of the bit:
tdc->tdco = can_bit_time(dbt) / 2
During benchmark tests, we could not find a clear advantages for one
of the two methods.
The tdco calculation is triggered each time the data_bittiming is
changed so that users relying on automated calculation can use the
netlink interface the exact same way without need of new parameters.
For example, a command such as:
ip link set canX type can bitrate 500000 dbitrate 4000000 fd on
would trigger the calculation.
The user using CONFIG_CAN_CALC_BITTIMING who does not want automated
calculation needs to manually set tdco to zero.
For example with:
ip link set canX type can tdco 0 bitrate 500000 dbitrate 4000000 fd on
(if the tdco parameter is provided in a previous command, it will be
overwritten).
If tdcv is set to zero (default), it is automatically calculated by
the transiver for each frame. As such, there is no code in the kernel
to calculate it.
tdcf has no automated calculation functions because we could not
figure out a formula for this parameter.
Link: https://lore.kernel.org/r/20210224002008.4158-6-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In order to implement byte queue limits (bql) in CAN drivers, the
length of the CAN frame needs to be passed into the networking stack
even if the transmission failed for some reason.
To avoid to calculate this length twice, extend can_free_echo_skb() to
return that value. Convert all users of this function, too.
This patch is the natural extension of commit:
| 9420e1d495 ("can: dev: can_get_echo_skb(): extend to return can
| frame length")
Link: https://lore.kernel.org/r/20210319142700.305648-3-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
There are two ref count variables controlling the free()ing of a socket:
- struct sock::sk_refcnt - which is changed by sock_hold()/sock_put()
- struct sock::sk_wmem_alloc - which accounts the memory allocated by
the skbs in the send path.
In case there are still TX skbs on the fly and the socket() is closed,
the struct sock::sk_refcnt reaches 0. In the TX-path the CAN stack
clones an "echo" skb, calls sock_hold() on the original socket and
references it. This produces the following back trace:
| WARNING: CPU: 0 PID: 280 at lib/refcount.c:25 refcount_warn_saturate+0x114/0x134
| refcount_t: addition on 0; use-after-free.
| Modules linked in: coda_vpu(E) v4l2_jpeg(E) videobuf2_vmalloc(E) imx_vdoa(E)
| CPU: 0 PID: 280 Comm: test_can.sh Tainted: G E 5.11.0-04577-gf8ff6603c617 #203
| Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
| Backtrace:
| [<80bafea4>] (dump_backtrace) from [<80bb0280>] (show_stack+0x20/0x24) r7:00000000 r6:600f0113 r5:00000000 r4:81441220
| [<80bb0260>] (show_stack) from [<80bb593c>] (dump_stack+0xa0/0xc8)
| [<80bb589c>] (dump_stack) from [<8012b268>] (__warn+0xd4/0x114) r9:00000019 r8:80f4a8c2 r7:83e4150c r6:00000000 r5:00000009 r4:80528f90
| [<8012b194>] (__warn) from [<80bb09c4>] (warn_slowpath_fmt+0x88/0xc8) r9:83f26400 r8:80f4a8d1 r7:00000009 r6:80528f90 r5:00000019 r4:80f4a8c2
| [<80bb0940>] (warn_slowpath_fmt) from [<80528f90>] (refcount_warn_saturate+0x114/0x134) r8:00000000 r7:00000000 r6:82b44000 r5:834e5600 r4:83f4d540
| [<80528e7c>] (refcount_warn_saturate) from [<8079a4c8>] (__refcount_add.constprop.0+0x4c/0x50)
| [<8079a47c>] (__refcount_add.constprop.0) from [<8079a57c>] (can_put_echo_skb+0xb0/0x13c)
| [<8079a4cc>] (can_put_echo_skb) from [<8079ba98>] (flexcan_start_xmit+0x1c4/0x230) r9:00000010 r8:83f48610 r7:0fdc0000 r6:0c080000 r5:82b44000 r4:834e5600
| [<8079b8d4>] (flexcan_start_xmit) from [<80969078>] (netdev_start_xmit+0x44/0x70) r9:814c0ba0 r8:80c8790c r7:00000000 r6:834e5600 r5:82b44000 r4:82ab1f00
| [<80969034>] (netdev_start_xmit) from [<809725a4>] (dev_hard_start_xmit+0x19c/0x318) r9:814c0ba0 r8:00000000 r7:82ab1f00 r6:82b44000 r5:00000000 r4:834e5600
| [<80972408>] (dev_hard_start_xmit) from [<809c6584>] (sch_direct_xmit+0xcc/0x264) r10:834e5600 r9:00000000 r8:00000000 r7:82b44000 r6:82ab1f00 r5:834e5600 r4:83f27400
| [<809c64b8>] (sch_direct_xmit) from [<809c6c0c>] (__qdisc_run+0x4f0/0x534)
To fix this problem, only set skb ownership to sockets which have still
a ref count > 0.
Fixes: 0ae89beb28 ("can: add destructor for self generated skbs")
Cc: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: Andre Naujoks <nautsch2@gmail.com>
Link: https://lore.kernel.org/r/20210226092456.27126-1-o.rempel@pengutronix.de
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Since 20dd3850bc ("can: Speed up CAN frame receiption by using
ml_priv") the CAN framework uses per device specific data in the AF_CAN
protocol. For this purpose the struct net_device->ml_priv is used. Later
the ml_priv usage in CAN was extended for other users, one of them being
CAN_J1939.
Later in the kernel ml_priv was converted to an union, used by other
drivers. E.g. the tun driver started storing it's stats pointer.
Since tun devices can claim to be a CAN device, CAN specific protocols
will wrongly interpret this pointer, which will cause system crashes.
Mostly this issue is visible in the CAN_J1939 stack.
To fix this issue, we request a dedicated CAN pointer within the
net_device struct.
Reported-by: syzbot+5138c4dd15a0401bec7b@syzkaller.appspotmail.com
Fixes: 20dd3850bc ("can: Speed up CAN frame receiption by using ml_priv")
Fixes: ffd956eef6 ("can: introduce CAN midlayer private and allocate it automatically")
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Fixes: 497a5757ce ("tun: switch to net core provided statistics counters")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20210223070127.4538-1-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The can_get_state_str() function is also relevant to the drivers. Export the
symbol and make it visible in the can/dev.h header.
Link: https://lore.kernel.org/r/20210119170355.12040-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.
To avoid to calculate this length twice, extend can_rx_offload_get_echo_skb()
to return that value. Convert all users of this function, too.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-15-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.
To avoid to calculate this length twice, extend can_get_echo_skb() to return
that value. Convert all users of this function, too.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-14-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add a frame_len argument to can_put_echo_skb() which is used to save length of
the CAN frame into field frame_len of struct can_skb_priv so that it can be
later used after transmission completion. Convert all users of this function,
too.
Drivers which implement BQL call can_put_echo_skb() with the output of
can_skb_get_frame_len(skb) and drivers which do not simply pass zero as an
input (in the same way that NULL would be given to can_get_echo_skb()). This
way, we have a nice symmetry between the two echo functions.
Link: https://lore.kernel.org/r/20210111061335.39983-1-mailhol.vincent@wanadoo.fr
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-13-mkl@pengutronix.de
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
In order to implement byte queue limits (bql) in CAN drivers, the length of the
CAN frame needs to be passed into the networking stack after queueing and after
transmission completion.
To avoid to calculate this length twice, extend the struct can_skb_priv to hold
the length of the CAN frame and extend __can_get_echo_skb() to return that
value.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-12-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds the function can_skb_get_frame_len() which returns the length
of a CAN frame on the data link layer, including Start-of-frame, Identifier,
various other bits, the actual data, the CRC, the End-of-frame, the Inter frame
spacing.
Co-developed-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Signed-off-by: Arunachalam Santhanam <arunachalam.santhanam@in.bosch.com>
Co-developed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Acked-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Co-developed-by: Marc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20210111141930.693847-11-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The data field in CAN-FD frames have specifig frame length (0, 1, 2, 3, 4, 5,
6, 7, 8, 12, 16, 20, 24, 32, 48, 64). This function "rounds" up a given length
to the next valid CAN-FD frame length.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-10-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch moves the netlink related code of the CAN device infrastructure into
a separate file.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch moves the skb related code of the CAN device infrastructure into a
separate file.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-6-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch moves all CAN frame length related code of the CAN device
infrastructure into a separate file.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-5-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch moves the bittiming related code of the CAN device infrastructure
into a separate file.
Reviewed-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20210111141930.693847-4-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds the following helper to functions to access Classical CAN DLC
values.
can_get_cc_dlc(): get the data length code for Classical CAN raw DLC access
can_frame_set_cc_len(): set len and len8_dlc value for Classical CAN raw DLC access
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110154913.1404582-2-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The helper functions can_len2dlc and can_dlc2len are only relevant for
CAN FD data length code (DLC) conversion.
To fit the introduced can_cc_dlc2len for Classical CAN we rename:
can_dlc2len -> can_fd_dlc2len to get the payload length from the DLC
can_len2dlc -> can_fd_len2dlc to get the DLC from the payload length
Suggested-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-6-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The naming of can_dlc as element of struct can_frame and also as variable
name is misleading as it claims to be a 'data length CODE' but in reality
it always was a plain data length.
With the indroduction of a new 'len' element in struct can_frame we can now
remove can_dlc as name and make clear which of the former uses was a plain
length (-> 'len') or a data length code (-> 'dlc') value.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201120100444.3199-1-socketcan@hartkopp.net
[mkl: gs_usb: keep struct gs_host_frame::can_dlc as is]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The macro was always used together with can_dlc2len() which sanitizes the
given dlc value on its own.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-4-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The get_can_dlc() macro is used to ensure the payload length information of
the Classical CAN frame to be max 8 bytes (the CAN_MAX_DLEN).
Rename the macro and use the correct constant in preparation of the len/dlc
cleanup for Classical CAN frames.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20201110101852.1973-3-socketcan@hartkopp.net
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
All user space generated SKBs are owned by a socket (unless injected into the
key via AF_PACKET). If a socket is closed, all associated skbs will be cleaned
up.
This leads to a problem when a CAN driver calls can_put_echo_skb() on a
unshared SKB. If the socket is closed prior to the TX complete handler,
can_get_echo_skb() and the subsequent delivering of the echo SKB to all
registered callbacks, a SKB with a refcount of 0 is delivered.
To avoid the problem, in can_get_echo_skb() the original SKB is now always
cloned, regardless of shared SKB or not. If the process exists it can now
safely discard its SKBs, without disturbing the delivery of the echo SKB.
The problem shows up in the j1939 stack, when it clones the incoming skb, which
detects the already 0 refcount.
We can easily reproduce this with following example:
testj1939 -B -r can0: &
cansend can0 1823ff40#0123
WARNING: CPU: 0 PID: 293 at lib/refcount.c:25 refcount_warn_saturate+0x108/0x174
refcount_t: addition on 0; use-after-free.
Modules linked in: coda_vpu imx_vdoa videobuf2_vmalloc dw_hdmi_ahb_audio vcan
CPU: 0 PID: 293 Comm: cansend Not tainted 5.5.0-rc6-00376-g9e20dcb7040d #1
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Backtrace:
[<c010f570>] (dump_backtrace) from [<c010f90c>] (show_stack+0x20/0x24)
[<c010f8ec>] (show_stack) from [<c0c3e1a4>] (dump_stack+0x8c/0xa0)
[<c0c3e118>] (dump_stack) from [<c0127fec>] (__warn+0xe0/0x108)
[<c0127f0c>] (__warn) from [<c01283c8>] (warn_slowpath_fmt+0xa8/0xcc)
[<c0128324>] (warn_slowpath_fmt) from [<c0539c0c>] (refcount_warn_saturate+0x108/0x174)
[<c0539b04>] (refcount_warn_saturate) from [<c0ad2cac>] (j1939_can_recv+0x20c/0x210)
[<c0ad2aa0>] (j1939_can_recv) from [<c0ac9dc8>] (can_rcv_filter+0xb4/0x268)
[<c0ac9d14>] (can_rcv_filter) from [<c0aca2cc>] (can_receive+0xb0/0xe4)
[<c0aca21c>] (can_receive) from [<c0aca348>] (can_rcv+0x48/0x98)
[<c0aca300>] (can_rcv) from [<c09b1fdc>] (__netif_receive_skb_one_core+0x64/0x88)
[<c09b1f78>] (__netif_receive_skb_one_core) from [<c09b2070>] (__netif_receive_skb+0x38/0x94)
[<c09b2038>] (__netif_receive_skb) from [<c09b2130>] (netif_receive_skb_internal+0x64/0xf8)
[<c09b20cc>] (netif_receive_skb_internal) from [<c09b21f8>] (netif_receive_skb+0x34/0x19c)
[<c09b21c4>] (netif_receive_skb) from [<c0791278>] (can_rx_offload_napi_poll+0x58/0xb4)
Fixes: 0ae89beb28 ("can: add destructor for self generated skbs")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: http://lore.kernel.org/r/20200124132656.22156-1-o.rempel@pengutronix.de
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Rename macro CAN_CALC_SYNC_SEG to CAN_SYNC_SEG and make it available
through include/linux/can/dev.h
Add an helper function can_bit_time() which returns the duration (in
time quanta) of one CAN bit.
Rationale for this patch: the sync segment and the bit time are two
concepts which are defined in the CAN ISO standard. Device drivers for
CAN might need those.
Please refer to ISO 11898-1:2015, section 11.3.1.1 "Bit time" for
additional information.
Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr>
Link: https://lore.kernel.org/r/20201002154219.4887-6-mailhol.vincent@wanadoo.fr
[mkl: Let can_bit_time() return an unsinged int, make argument const]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds a new initialization function:
can_rx_offload_add_manual()
It should be used to add support rx-offload to a driver, if the callback
mechanism should not be used. Use e.g. can_rx_offload_queue_sorted() to queue
skbs into rx-offload.
Link: https://lore.kernel.org/r/20200915223527.1417033-33-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The function can_put_echo_skb() can fail for several reasons. It may
fail due to OOM, but when it fails it's usually due to locking problems
in the driver.
In order to help developing and debugging of new drivers propagate error
value in case of errors.
Link: https://lore.kernel.org/r/20200915223527.1417033-12-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
KMSAN sysbot detected a read access to an untinitialized value in the
headroom of an outgoing CAN related sk_buff. When using CAN sockets this
area is filled appropriately - but when using a packet socket this
initialization is missing.
The problematic read access occurs in the CAN receive path which can
only be triggered when the sk_buff is sent through a (virtual) CAN
interface. So we check in the sending path whether we need to perform
the missing initializations.
Fixes: d3b58c47d3 ("can: replace timestamp as unique skb attribute")
Reported-by: syzbot+b02ff0707a97e4e79ebb@syzkaller.appspotmail.com
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org> # >= v4.1
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
In j1939 we need our own struct sock::sk_destruct callback. Export the
generic af_can can_sock_destruct() that allows us to chain-call it.
Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
The skbs for classic CAN and CAN FD frames are allocated with seperate
functions: alloc_can_skb() and alloc_canfd_skb().
In order to support CAN FD frames via the rx-offload helper, the driver
itself has to allocate the skb (depending whether it received a classic
CAN or CAN FD frame), as the rx-offload helper cannot know which kind of
CAN frame the driver has received.
This patch moves the allocation of the skb into the struct
can_rx_offload::mailbox_read callbacks of the the flexcan and ti_hecc
driver and adjusts the rx-offload helper accordingly.
Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch removes the function can_rx_offload_reset(), as it does
nothing. If we ever need this function, add it back again.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Instead of using legacy platform data, switch to use device properties.
For clock frequency we are using well established clock-frequency property.
Users, two for now, are also converted here.
Cc: Daniel Mack <daniel@zonque.org>
Cc: Haojian Zhuang <haojian.zhuang@gmail.com>
Cc: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Merge tag 'linux-can-next-for-5.4-20190904' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next
Marc Kleine-Budde says:
====================
pull-request: can-next 2019-09-04 j1939
this is a pull request for net-next/master consisting of 21 patches.
the first 12 patches are by me and target the CAN core infrastructure.
They clean up the names of variables , structs and struct members,
convert can_rx_register() to use max() instead of open coding it and
remove unneeded code from the can_pernet_exit() callback.
The next three patches are also by me and they introduce and make use of
the CAN midlayer private structure. It is used to hold protocol specific
per device data structures.
The next patch is by Oleksij Rempel, switches the
&net->can.rcvlists_lock from a spin_lock() to a spin_lock_bh(), so that
it can be used from NAPI (soft IRQ) context.
The next 4 patches are by Kurt Van Dijck, he first updates his email
address via mailmap and then extends sockaddr_can to include j1939
members.
The final patch is the collective effort of many entities (The j1939
authors: Oliver Hartkopp, Bastian Stender, Elenita Hinds, kbuild test
robot, Kurt Van Dijck, Maxime Jayat, Robin van der Gracht, Oleksij
Rempel, Marc Kleine-Budde). It adds support of SAE J1939 protocol to the
CAN networking stack.
SAE J1939 is the vehicle bus recommended practice used for communication
and diagnostics among vehicle components. Originating in the car and
heavy-duty truck industry in the United States, it is now widely used in
other parts of the world.
P.S.: This pull request doesn't invalidate my last pull request:
"pull-request: can-next 2019-09-03".
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
SAE J1939 is the vehicle bus recommended practice used for communication
and diagnostics among vehicle components. Originating in the car and
heavy-duty truck industry in the United States, it is now widely used in
other parts of the world.
J1939, ISO 11783 and NMEA 2000 all share the same high level protocol.
SAE J1939 can be considered the replacement for the older SAE J1708 and
SAE J1587 specifications.
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Bastian Stender <bst@pengutronix.de>
Signed-off-by: Elenita Hinds <ecathinds@gmail.com>
Signed-off-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Signed-off-by: Maxime Jayat <maxime.jayat@mobile-devices.fr>
Signed-off-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The size of this structure will be increased with J1939 support. To stay
binary compatible, the CAN_REQUIRED_SIZE macro is introduced for
existing CAN protocols.
Signed-off-by: Kurt Van Dijck <dev.kurt@vandijck-laurijssen.be>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch removes the old method of allocating the per device protocol
specific memory via a netdevice_notifier. This had the drawback, that
the allocation can fail, leading to a lot of null pointer checks in the
code. This also makes the live cycle management of this memory quite
complicated.
This patch switches from the allocating the struct can_dev_rcv_lists in
a NETDEV_REGISTER call to using the dev->ml_priv, which is allocated by
the driver since the previous patch.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch introduces the CAN midlayer private structure ("struct
can_ml_priv") which should be used to hold protocol specific per device
data structures. For now it's only member is "struct can_dev_rcv_lists".
The CAN midlayer private is allocated via alloc_netdev()'s private and
assigned to "struct net_device::ml_priv" during device creation. This is
done transparently for CAN drivers using alloc_candev(). The slcan, vcan
and vxcan drivers which are not using alloc_candev() have been adopted
manually. The memory layout of the netdev_priv allocated via
alloc_candev() will looke like this:
+-------------------------+
| driver's priv |
+-------------------------+
| struct can_ml_priv |
+-------------------------+
| array of struct sk_buff |
+-------------------------+
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
All R-Car platforms use DT for describing CAN controllers. R-Car CAN
platform data support was never used in any upstream kernel.
Move the Clock Select Register settings enum into the driver, and remove
platform data support and the corresponding header file.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add missing SPDX identifiers for the CAN network layer and correct the SPDX
license for two of its include files to make sure the BSD-3-Clause applies
for the entire subsystem.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
With commit c7cbdbf29f ("net: rework SIOCGSTAMP ioctl handling") the only
ioctl function in can_ioctl() has been removed.
As this SIOCGSTAMP ioctl command is now handled in net/socket.c we can entirely
remove the CAN specific ioctl functions.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Based on 2 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 version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the version 2 of the gnu general public
license as published by the free software foundation 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
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 10 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.259525894@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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 version 2 of the license 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
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 100 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.918357685@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function has nothing todo with error.
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Current CAN framework can't guarantee proper/chronological order
of RX and TX-ECHO messages. To make this possible, drivers should use
this functions instead of can_get_echo_skb().
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch factors out all non sending parts of can_get_echo_skb() into
a seperate function __can_get_echo_skb(), so that it can be re-used in
an upcoming patch.
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The existing SocketCAN implementation provides alloc_candev() to
allocate a CAN device using a single Tx and Rx queue. This can lead to
priority inversion in case the single Tx queue is already full with low
priority messages and a high priority message needs to be sent while the
bus is fully loaded with medium priority messages.
This problem can be solved by using the existing multi-queue support of
the network subsytem. The commit makes it possible to use multi-queue in
the CAN subsystem in the same way it is used in the Ethernet subsystem
by adding an alloc_candev_mqs() call and accompanying macros. With this
support a CAN device can use multi-queue qdisc (e.g. mqprio) to avoid
the aforementioned priority inversion.
The exisiting functionality of alloc_candev() is the same as before.
CAN devices need to have prioritized multiple hardware queues or are
able to abort waiting for arbitration to make sensible use of
multi-queues.
Signed-off-by: Zhu Yi <yi.zhu5@cn.bosch.com>
Signed-off-by: Mark Jonas <mark.jonas@de.bosch.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Various CAN or CAN-FD IP may be able to run at a faster rate than
what the transceiver the CAN node is connected to. This can lead to
unexpected errors. However, CAN transceivers typically have fixed
limitations and provide no means to discover these limitations at
runtime. Therefore, add support for a can-transceiver node that
can be reused by other CAN peripheral drivers to determine for both
CAN and CAN-FD what the max bitrate that can be used. If the user
tries to configure CAN to pass these maximum bitrates it will throw
an error.
Also add support for reading bitrate_max via the netlink interface.
Reviewed-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
[nsekhar@ti.com: fix build error with !CONFIG_OF]
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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>
The statistics and its proc output was not implemented as per-net in the
initial network namespace support by Mario Kicherer (8e8cda6d73).
This patch adds the missing per-net statistics for the CAN subsystem.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds the support of the PCAN-PCI Express FD boards made
by PEAK-System, for computers using the PCI Express slot.
The PCAN-PCI Express FD has one or two CAN FD channels, depending
on the model. A galvanic isolation of the CAN ports protects
the electronics of the card and the respective computer against
disturbances of up to 500 Volts. The PCAN-PCI Express FD can be operated
with ambient temperatures in a range of -40 to +85 °C.
Such boards run an extented version of the CAN-FD IP running into USB
CAN-FD interfaces from PEAK-System, so this patch adds several new commands
and their corresponding data types to the PEAK CAN-FD common definitions
header file too.
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The CAN-FD IP from PEAK-System runs into several kinds of PC CAN-FD
interfaces. Up to now, only the USB CAN-FD adapters were supported by
the Kernel. In order to prepare the adding of some new non-USB CAN-FD
interfaces, this patch moves - and rename - the IP definitions file
from its private (usb) sub-directory into a - newly created - CAN specific
one.
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds initial support for network namespaces. The changes only
enable support in the CAN raw, proc and af_can code. GW and BCM still
have their checks that ensure that they are used only from the main
namespace.
The patch boils down to moving the global structures, i.e. the global
filter list and their /proc stats, into a per-namespace structure and passing
around the corresponding "struct net" in a lot of different places.
Changes since v1:
- rebased on current HEAD (2bfe01e)
- fixed overlong line
Signed-off-by: Mario Kicherer <dev@kicherer.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch converts TI HECC driver to DT only driver. This results in
removing ti_hecc.h containing now obsolete platform data.
Former transceiver_switch callback function will be now modelled via
regulator API.
Signed-off-by: Anton Glukhov <anton.a.glukhov@gmail.com>
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Some CAN controllers don't implement a FIFO in hardware, but fill their
mailboxes in a particular order (from lowest to highest or highest to lowest).
This makes problems to read the frames in the correct order from the hardware,
as new frames might be filled into just read (low) mailboxes. This gets worse,
when following new frames are received into not read (higher) mailboxes.
On the bright side some these CAN controllers put a timestamp on each received
CAN frame. This patch adds support to offload CAN frames in interrupt context,
order them by timestamp and then transmitted in a NAPI context.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Some CAN controllers have a usable FIFO already but can still benefit
from off-loading the CAN controller FIFO. The CAN frames of the FIFO are
read and put into a skb queue during interrupt and then transmitted in a
NAPI context.
Signed-off-by: David Jander <david@protonic.nl>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Zhang Yanmin reported crashes [1] and provided a patch adding a
synchronize_rcu() call in can_rx_unregister()
The main problem seems that the sockets themselves are not RCU
protected.
If CAN uses RCU for delivery, then sockets should be freed only after
one RCU grace period.
Recent kernels could use sock_set_flag(sk, SOCK_RCU_FREE), but let's
ease stable backports with the following fix instead.
[1]
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff81495e25>] selinux_socket_sock_rcv_skb+0x65/0x2a0
Call Trace:
<IRQ>
[<ffffffff81485d8c>] security_sock_rcv_skb+0x4c/0x60
[<ffffffff81d55771>] sk_filter+0x41/0x210
[<ffffffff81d12913>] sock_queue_rcv_skb+0x53/0x3a0
[<ffffffff81f0a2b3>] raw_rcv+0x2a3/0x3c0
[<ffffffff81f06eab>] can_rcv_filter+0x12b/0x370
[<ffffffff81f07af9>] can_receive+0xd9/0x120
[<ffffffff81f07beb>] can_rcv+0xab/0x100
[<ffffffff81d362ac>] __netif_receive_skb_core+0xd8c/0x11f0
[<ffffffff81d36734>] __netif_receive_skb+0x24/0xb0
[<ffffffff81d37f67>] process_backlog+0x127/0x280
[<ffffffff81d36f7b>] net_rx_action+0x33b/0x4f0
[<ffffffff810c88d4>] __do_softirq+0x184/0x440
[<ffffffff81f9e86c>] do_softirq_own_stack+0x1c/0x30
<EOI>
[<ffffffff810c76fb>] do_softirq.part.18+0x3b/0x40
[<ffffffff810c8bed>] do_softirq+0x1d/0x20
[<ffffffff81d30085>] netif_rx_ni+0xe5/0x110
[<ffffffff8199cc87>] slcan_receive_buf+0x507/0x520
[<ffffffff8167ef7c>] flush_to_ldisc+0x21c/0x230
[<ffffffff810e3baf>] process_one_work+0x24f/0x670
[<ffffffff810e44ed>] worker_thread+0x9d/0x6f0
[<ffffffff810e4450>] ? rescuer_thread+0x480/0x480
[<ffffffff810ebafc>] kthread+0x12c/0x150
[<ffffffff81f9ccef>] ret_from_fork+0x3f/0x70
Reported-by: Zhang Yanmin <yanmin.zhang@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some CAN interfaces only support fixed fixed bitrates. This patch adds a
netlink interface to get the list of the CAN interface's fixed bitrates and
data bitrates.
Inside the driver arrays of supported data- bitrate values are defined.
const u32 drvname_bitrate[] = { 20000, 50000, 100000 };
const u32 drvname_data_bitrate[] = { 200000, 500000, 1000000 };
struct drvname_priv *priv;
priv = netdev_priv(dev);
priv->bitrate_const = drvname_bitrate;
priv->bitrate_const_cnt = ARRAY_SIZE(drvname_bitrate);
priv->data_bitrate_const = drvname_data_bitrate;
priv->data_bitrate_const_cnt = ARRAY_SIZE(drvname_data_bitrate);
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch adds a netlink interface to configure the CAN bus termination of
CAN interfaces.
Inside the driver an array of supported termination values is defined:
const u16 drvname_termination[] = { 60, 120, CAN_TERMINATION_DISABLED };
struct drvname_priv *priv;
priv = netdev_priv(dev);
priv->termination_const = drvname_termination;
priv->termination_const_cnt = ARRAY_SIZE(drvname_termination);
priv->termination = CAN_TERMINATION_DISABLED;
And the funtion to set the value has to be defined:
priv->do_set_termination = drvname_set_termination;
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Reviewed-by: Ramesh Shanmugasundaram <Ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
A timer was used to restart after the bus-off state, leading to a
relatively large can_restart() executed in an interrupt context,
which in turn sets up pinctrl. When this happens during system boot,
there is a high probability of grabbing the pinctrl_list_mutex,
which is locked already by the probe() of other device, making the
kernel suspect a deadlock condition [1].
To resolve this issue, the restart_timer is replaced by a delayed
work.
[1] https://github.com/victronenergy/venus/issues/24
Signed-off-by: Sergei Miroshnichenko <sergeimir@emcraft.com>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As described in 'can: m_can: tag current CAN FD controllers as non-ISO'
(6cfda7fbeb) it is possible to define fixed configuration options by
setting the according bit in 'ctrlmode' and clear it in 'ctrlmode_supported'.
This leads to the incovenience that the fixed configuration bits can not be
passed by netlink even when they have the correct values (e.g. non-ISO, FD).
This patch fixes that issue and not only allows fixed set bit values to be set
again but now requires(!) to provide these fixed values at configuration time.
A valid CAN FD configuration consists of a nominal/arbitration bittiming, a
data bittiming and a control mode with CAN_CTRLMODE_FD set - which is now
enforced by a new can_validate() function. This fix additionally removed the
inconsistency that was prohibiting the support of 'CANFD-only' controller
drivers, like the RCar CAN FD.
For this reason a new helper can_set_static_ctrlmode() has been introduced to
provide a proper interface to handle static enabled CAN controller options.
Reported-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Reviewed-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Cc: <stable@vger.kernel.org> # >= 3.18
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
This patch makes can_dropped_invalid_skb return bool due to this
particular function only using either one or zero as its return
value.
No functional change.
Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the missing #include-s to the dev.h and led.h, so that they can
be used without including further header files.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Commit 514ac99c64 "can: fix multiple delivery of a single CAN frame for
overlapping CAN filters" requires the skb->tstamp to be set to check for
identical CAN skbs.
Without timestamping to be required by user space applications this timestamp
was not generated which lead to commit 36c01245eb "can: fix loss of CAN frames
in raw_rcv" - which forces the timestamp to be set in all CAN related skbuffs
by introducing several __net_timestamp() calls.
This forces e.g. out of tree drivers which are not using alloc_can{,fd}_skb()
to add __net_timestamp() after skbuff creation to prevent the frame loss fixed
in mainline Linux.
This patch removes the timestamp dependency and uses an atomic counter to
create an unique identifier together with the skbuff pointer.
Btw: the new skbcnt element introduced in struct can_skb_priv has to be
initialized with zero in out-of-tree drivers which are not using
alloc_can{,fd}_skb() too.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Cc: linux-stable <stable@vger.kernel.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add <ifname>-rxtx trigger, that will be activated both for tx
as rx events. This trigger mimics "activity" LED for Ethernet
devices.
Signed-off-by: Yegor Yefremov <yegorslists@googlemail.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
It is identical to the can destructor.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The handling of can error states is different between platforms.
This is an attempt to correct that problem.
I've moved this handling into a generic function for changing the
error state. This ensures that error state changes are handled
the same way everywhere (where this function is used).
This new mechanism also adds reverse state transitioning in error
frames, i.e. the user will be notified through the socket interface
when the state goes down.
Signed-off-by: Andri Yngvason <andri.yngvason@marel.com>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The CAN device drivers can use can_is_canfd_skb() to check if the frame to send
is on CAN FD mode or normal CAN mode.
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Dong Aisheng <b29396@freescale.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Armin pointed me to the fact that the identifier which is used to ensure the
unique include processing in lunux/include/uapi/linux/can.h is CAN_H.
This clashed with his own source as includes from libraries and APIs should
use an underscore '_' at the identifier start.
This patch fixes the protection identifiers in all CAN relavant includes.
Reported-by: Armin Burchardt <armin@uni-bremen.de>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Add support for the CAN controller found in Renesas R-Car SoCs.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
The configuration for CAN FD depends on CAN_CTRLMODE_FD enabled in the driver
specific ctrlmode_supported capabilities.
The configuration can be done either with the 'fd { on | off }' option in the
'ip' tool from iproute2 or by setting the CAN netdevice MTU to CAN_MTU (16) or
to CANFD_MTU (72).
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
As CAN FD offers a second bitrate for the data section of the CAN frame the
infrastructure for storing and configuring this second bitrate is introduced.
Improved the readability of the if-statement by inserting some newlines.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Stephane Grosjean <s.grosjean@peak-system.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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Merge tag 'linux-can-next-for-3.15-20140212' of git://gitorious.org/linux-can/linux-can-next
linux-can-next-for-3.15-20140212
Marc Kleine-Budde says:
====================
this is a pull request of eight patches for net-next/master.
Florian Vaussard contributed a series that merged the sja1000 of_platform
into the platform driver. The of_platform driver is finally removed.
Stephane Grosjean supplied a patch to allocate CANFD skbs. In a patch
by Uwe Kleine-König another missing copyright information was added to
a userspace header. And a patch by Yoann DI RUZZA that adds listen only
mode to the at91_can driver.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the ability of allocating a CANFD frame data structure in the
skb data area.
Signed-off-by: Stephane Grosjean <s.grosjean@peak-system.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Self generated skbuffs in net/can/bcm.c are setting a skb->sk reference but
no explicit destructor which is enforced since Linux 3.11 with commit
376c7311bd (net: add a temporary sanity check in skb_orphan()).
This patch adds some helper functions to make sure that a destructor is
properly defined when a sock reference is assigned to a CAN related skb.
To create an unshared skb owned by the original sock a common helper function
has been introduced to replace open coded functions to create CAN echo skbs.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Tested-by: Andre Naujoks <nautsch2@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>