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2021-08-19can: dev: provide optional GPIO based termination supportOleksij Rempel
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>
2021-07-25can: flexcan: add platform data headerAngelo Dureghello
Add platform data header for flexcan. Link: https://lore.kernel.org/r/20210702094841.327679-1-angelo@kernel-space.org Signed-off-by: Angelo Dureghello <angelo@kernel-space.org> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-07-25can: bittiming: fix documentation for struct can_tdcMarc Kleine-Budde
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: 289ea9e4ae59 ("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>
2021-07-25can: rx-offload: can_rx_offload_threaded_irq_finish(): add new function to ↵Marc Kleine-Budde
be called from threaded interrupt 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>
2021-07-25can: rx-offload: can_rx_offload_irq_finish(): directly call napi_schedule()Marc Kleine-Budde
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>
2021-07-25can: rx-offload: add skb queue for use during ISRMarc Kleine-Budde
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>
2021-03-30can: bittiming: add CAN_KBPS, CAN_MBPS and CAN_MHZ macrosVincent Mailhol
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>
2021-03-30can: bittiming: add calculation for CAN FD Transmitter Delay Compensation (TDC)Vincent Mailhol
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>
2021-03-30can: dev: reorder struct can_priv members for better packingVincent Mailhol
Save eight bytes of holes on x86-64 architectures by reordering struct can_priv members. Before: $ pahole -C can_priv drivers/net/can/dev/dev.o struct can_priv { struct net_device * dev; /* 0 8 */ struct can_device_stats can_stats; /* 8 24 */ struct can_bittiming bittiming; /* 32 32 */ /* --- cacheline 1 boundary (64 bytes) --- */ struct can_bittiming data_bittiming; /* 64 32 */ const struct can_bittiming_const * bittiming_const; /* 96 8 */ const struct can_bittiming_const * data_bittiming_const; /* 104 8 */ struct can_tdc tdc; /* 112 12 */ /* XXX 4 bytes hole, try to pack */ /* --- cacheline 2 boundary (128 bytes) --- */ const struct can_tdc_const * tdc_const; /* 128 8 */ const u16 * termination_const; /* 136 8 */ unsigned int termination_const_cnt; /* 144 4 */ u16 termination; /* 148 2 */ /* XXX 2 bytes hole, try to pack */ const u32 * bitrate_const; /* 152 8 */ unsigned int bitrate_const_cnt; /* 160 4 */ /* XXX 4 bytes hole, try to pack */ const u32 * data_bitrate_const; /* 168 8 */ unsigned int data_bitrate_const_cnt; /* 176 4 */ u32 bitrate_max; /* 180 4 */ struct can_clock clock; /* 184 4 */ enum can_state state; /* 188 4 */ /* --- cacheline 3 boundary (192 bytes) --- */ u32 ctrlmode; /* 192 4 */ u32 ctrlmode_supported; /* 196 4 */ u32 ctrlmode_static; /* 200 4 */ int restart_ms; /* 204 4 */ struct delayed_work restart_work; /* 208 168 */ /* XXX last struct has 4 bytes of padding */ /* --- cacheline 5 boundary (320 bytes) was 56 bytes ago --- */ int (*do_set_bittiming)(struct net_device *); /* 376 8 */ /* --- cacheline 6 boundary (384 bytes) --- */ int (*do_set_data_bittiming)(struct net_device *); /* 384 8 */ int (*do_set_mode)(struct net_device *, enum can_mode); /* 392 8 */ int (*do_set_termination)(struct net_device *, u16); /* 400 8 */ int (*do_get_state)(const struct net_device *, enum can_state *); /* 408 8 */ int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 416 8 */ unsigned int echo_skb_max; /* 424 4 */ /* XXX 4 bytes hole, try to pack */ struct sk_buff * * echo_skb; /* 432 8 */ /* size: 440, cachelines: 7, members: 31 */ /* sum members: 426, holes: 4, sum holes: 14 */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 56 bytes */ }; After: $ pahole -C can_priv drivers/net/can/dev/dev.o struct can_priv { struct net_device * dev; /* 0 8 */ struct can_device_stats can_stats; /* 8 24 */ const struct can_bittiming_const * bittiming_const; /* 32 8 */ const struct can_bittiming_const * data_bittiming_const; /* 40 8 */ struct can_bittiming bittiming; /* 48 32 */ /* --- cacheline 1 boundary (64 bytes) was 16 bytes ago --- */ struct can_bittiming data_bittiming; /* 80 32 */ const struct can_tdc_const * tdc_const; /* 112 8 */ struct can_tdc tdc; /* 120 12 */ /* --- cacheline 2 boundary (128 bytes) was 4 bytes ago --- */ unsigned int bitrate_const_cnt; /* 132 4 */ const u32 * bitrate_const; /* 136 8 */ const u32 * data_bitrate_const; /* 144 8 */ unsigned int data_bitrate_const_cnt; /* 152 4 */ u32 bitrate_max; /* 156 4 */ struct can_clock clock; /* 160 4 */ unsigned int termination_const_cnt; /* 164 4 */ const u16 * termination_const; /* 168 8 */ u16 termination; /* 176 2 */ /* XXX 2 bytes hole, try to pack */ enum can_state state; /* 180 4 */ u32 ctrlmode; /* 184 4 */ u32 ctrlmode_supported; /* 188 4 */ /* --- cacheline 3 boundary (192 bytes) --- */ u32 ctrlmode_static; /* 192 4 */ int restart_ms; /* 196 4 */ struct delayed_work restart_work; /* 200 168 */ /* XXX last struct has 4 bytes of padding */ /* --- cacheline 5 boundary (320 bytes) was 48 bytes ago --- */ int (*do_set_bittiming)(struct net_device *); /* 368 8 */ int (*do_set_data_bittiming)(struct net_device *); /* 376 8 */ /* --- cacheline 6 boundary (384 bytes) --- */ int (*do_set_mode)(struct net_device *, enum can_mode); /* 384 8 */ int (*do_set_termination)(struct net_device *, u16); /* 392 8 */ int (*do_get_state)(const struct net_device *, enum can_state *); /* 400 8 */ int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 408 8 */ unsigned int echo_skb_max; /* 416 4 */ /* XXX 4 bytes hole, try to pack */ struct sk_buff * * echo_skb; /* 424 8 */ /* size: 432, cachelines: 7, members: 31 */ /* sum members: 426, holes: 2, sum holes: 6 */ /* paddings: 1, sum paddings: 4 */ /* last cacheline: 48 bytes */ }; Link: https://lore.kernel.org/r/20210224002008.4158-3-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: add new CAN FD bittiming parameters: Transmitter Delay Compensation (TDC)Vincent Mailhol
At high bit rates, the propagation delay from the TX pin to the RX pin of the transceiver causes measurement errors: the sample point on the RX pin might occur on the previous bit. This issue is addressed in ISO 11898-1 section 11.3.3 "Transmitter delay compensation" (TDC). This patch adds two new structures: can_tdc and can_tdc_const in order to implement this TDC. The structures are then added to can_priv. A controller supports TDC if an only if can_priv::tdc_const is not NULL. TDC is active if and only if: - fd flag is on - can_priv::tdc.tdco is not zero. It is the driver responsibility to check those two conditions are met. No new controller modes are introduced (i.e. no CAN_CTRL_MODE_TDC) in order not to be redundant with above logic. The names of the parameters are chosen to match existing CAN controllers specification. References: - Bosch C_CAN FD8: https://www.bosch-semiconductors.com/media/ip_modules/pdf_2/c_can_fd8/users_manual_c_can_fd8_r210_1.pdf - Microchip CAN FD Controller Module: http://ww1.microchip.com/downloads/en/DeviceDoc/MCP251XXFD-CAN-FD-Controller-Module-Family-Reference-Manual-20005678B.pdf - SAM E701/S70/V70/V71 Family: https://www.mouser.com/datasheet/2/268/60001527A-1284321.pdf Link: https://lore.kernel.org/r/20210224002008.4158-2-mailhol.vincent@wanadoo.fr Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2021-03-30can: dev: can_free_echo_skb(): extend to return can frame lengthMarc Kleine-Budde
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: | 9420e1d495e2 ("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>
2021-03-01can: skb: can_skb_set_owner(): fix ref counting if socket was closed before ↵Oleksij Rempel
setting skb ownership 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: 0ae89beb283a ("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>
2021-02-24net: introduce CAN specific pointer in the struct net_deviceOleksij Rempel
Since 20dd3850bcf8 ("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: 20dd3850bcf8 ("can: Speed up CAN frame receiption by using ml_priv") Fixes: ffd956eef69b ("can: introduce CAN midlayer private and allocate it automatically") Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Fixes: 497a5757ce4e ("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>
2021-01-27can: dev: export can_get_state_str() functionVincent Mailhol
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>
2021-01-14can: dev: can_rx_offload_get_echo_skb(): extend to return can frame lengthMarc Kleine-Budde
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>
2021-01-14can: dev: can_get_echo_skb(): extend to return can frame lengthMarc Kleine-Budde
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>
2021-01-14can: dev: can_put_echo_skb(): extend to handle frame_lenVincent Mailhol
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>
2021-01-14can: dev: extend struct can_skb_priv to hold CAN frame lengthMarc Kleine-Budde
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>
2021-01-14can: length: can_skb_get_frame_len(): introduce function to get data length ↵Vincent Mailhol
of frame in data link layer 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>
2021-01-14can: length: canfd_sanitize_len(): add function to sanitize CAN-FD data lengthMarc Kleine-Budde
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>
2021-01-13can: dev: move netlink related code into seperate fileMarc Kleine-Budde
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>
2021-01-13can: dev: move skb related into seperate fileMarc Kleine-Budde
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>
2021-01-13can: dev: move length related code into seperate fileMarc Kleine-Budde
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>
2021-01-13can: dev: move bittiming related code into seperate fileMarc Kleine-Budde
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>
2020-11-20can: drivers: introduce helpers to access Classical CAN DLC valuesOliver Hartkopp
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>
2020-11-20can: rename CAN FD related can_len2dlc and can_dlc2len helpersOliver Hartkopp
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>
2020-11-20can: replace can_dlc as variable/element for payload lengthOliver Hartkopp
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>
2020-11-20can: remove obsolete get_canfd_dlc() macroOliver Hartkopp
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>
2020-11-20can: rename get_can_dlc() macro with can_cc_dlc2len()Oliver Hartkopp
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>
2020-11-03can: can_create_echo_skb(): fix echo skb generation: always use skb_clone()Oleksij Rempel
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: 0ae89beb283a ("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>
2020-10-12can: remove obsolete version stringsOliver Hartkopp
As pointed out by Jakub Kicinski here: http://lore.kernel.org/r/20201009175751.5c54097f@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com this patch removes the obsolete version information of the different CAN protocols and the AF_CAN core module. Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20201012074354.25839-2-socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2020-10-07can: dev: add a helper function to calculate the duration of one bitVincent Mailhol
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>
2020-10-06can: dev: fix type of get_can_dlc() and get_canfd_dlc() macrosVincent Mailhol
The macros get_can_dlc() and get_canfd_dlc() are not visible in userland. As such, type u8 should be preferred over type __u8. Reference: https://lkml.org/lkml/2020/10/1/708 Signed-off-by: Vincent Mailhol <mailhol.vincent@wanadoo.fr> Link: https://lore.kernel.org/r/20201002154219.4887-3-mailhol.vincent@wanadoo.fr Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2020-09-21can: rx-offload: can_rx_offload_add_manual(): add new initialization functionMarc Kleine-Budde
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>
2020-09-21can: dev: can_put_echo_skb(): propagate error in case of errorsMarc Kleine-Budde
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>
2020-09-21can: include: fix spelling mistakesMarc Kleine-Budde
This patch fixes spelling erros found by "codespell" in the include/linux/can subtree. Link: https://lore.kernel.org/r/20200915223527.1417033-4-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2020-06-15can: Replace zero-length array with flexible-arrayGustavo A. R. Silva
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>
2020-04-18can: dev: peak_canfd.h: Replace zero-length array with flexible-array memberGustavo A. R. Silva
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 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
2020-01-02can: can_dropped_invalid_skb(): ensure an initialized headroom in outgoing ↵Oliver Hartkopp
CAN sk_buffs 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: d3b58c47d330d ("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>
2019-11-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Lots of overlapping changes and parallel additions, stuff like that. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-13can: af_can: export can_sock_destruct()Oleksij Rempel
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: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
2019-11-11can: rx-offload: Prepare for CAN FD supportJoakim Zhang
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>
2019-11-11can: rx-offload: can_rx_offload_reset(): remove no-op functionMarc Kleine-Budde
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>
2019-11-11can: mcp251x: get rid of legacy platform dataAndy Shevchenko
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>
2019-09-05Merge tag 'linux-can-next-for-5.4-20190904' of ↵David S. Miller
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>
2019-09-04can: add support of SAE J1939 protocolThe j1939 authors
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>
2019-09-04can: introduce CAN_REQUIRED_SIZE macroKurt Van Dijck
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>
2019-09-04can: make use of preallocated can_ml_priv for per device struct ↵Marc Kleine-Budde
can_dev_rcv_lists 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>
2019-09-04can: introduce CAN midlayer private and allocate it automaticallyMarc Kleine-Budde
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>
2019-09-03can: dev: avoid long linesMarc Kleine-Budde
This patch fixes long lines in the generic CAN device infrastructure. Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>