From patchwork Sat Oct 9 13:13:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Mailhol X-Patchwork-Id: 12547687 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6B12C433EF for ; Sat, 9 Oct 2021 13:13:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C1FAE6103B for ; Sat, 9 Oct 2021 13:13:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233560AbhJINP2 (ORCPT ); Sat, 9 Oct 2021 09:15:28 -0400 Received: from smtp03.smtpout.orange.fr ([80.12.242.125]:51497 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233022AbhJINPV (ORCPT ); Sat, 9 Oct 2021 09:15:21 -0400 Received: from tomoyo.flets-east.jp ([114.149.34.46]) by smtp.orange.fr with ESMTPA id ZC9zmoEn4UGqlZCADm2ie4; Sat, 09 Oct 2021 15:13:24 +0200 X-ME-Helo: tomoyo.flets-east.jp X-ME-Auth: MDU0YmViZGZmMDIzYiBlMiM2NTczNTRjNWZkZTMwOGRiOGQ4ODf3NWI1ZTMyMzdiODlhOQ== X-ME-Date: Sat, 09 Oct 2021 15:13:24 +0200 X-ME-IP: 114.149.34.46 From: Vincent Mailhol To: Marc Kleine-Budde , linux-can@vger.kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Vincent Mailhol Subject: [PATCH v2 1/3] can: dev: replace can_priv::ctrlmode_static by can_get_static_ctrlmode() Date: Sat, 9 Oct 2021 22:13:02 +0900 Message-Id: <20211009131304.19729-2-mailhol.vincent@wanadoo.fr> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211009131304.19729-1-mailhol.vincent@wanadoo.fr> References: <20211009131304.19729-1-mailhol.vincent@wanadoo.fr> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org 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. A condition sine qua non for this to work is that the controller static modes should never be set in can_priv::ctrlmode_supported. This is already the case for existing drivers, however, we added a warning message in can_set_static_ctrlmode() to check that. Signed-off-by: Vincent Mailhol --- drivers/net/can/dev/dev.c | 5 +++-- drivers/net/can/dev/netlink.c | 2 +- include/linux/can/dev.h | 12 ++++++++++-- 3 files changed, 14 insertions(+), 5 deletions(-) diff --git a/drivers/net/can/dev/dev.c b/drivers/net/can/dev/dev.c index e3d840b81357..59c79f92fccc 100644 --- a/drivers/net/can/dev/dev.c +++ b/drivers/net/can/dev/dev.c @@ -300,6 +300,7 @@ EXPORT_SYMBOL_GPL(free_candev); int can_change_mtu(struct net_device *dev, int new_mtu) { struct can_priv *priv = netdev_priv(dev); + u32 ctrlmode_static = can_get_static_ctrlmode(priv); /* Do not allow changing the MTU while running */ if (dev->flags & IFF_UP) @@ -309,7 +310,7 @@ int can_change_mtu(struct net_device *dev, int new_mtu) switch (new_mtu) { case CAN_MTU: /* 'CANFD-only' controllers can not switch to CAN_MTU */ - if (priv->ctrlmode_static & CAN_CTRLMODE_FD) + if (ctrlmode_static & CAN_CTRLMODE_FD) return -EINVAL; priv->ctrlmode &= ~CAN_CTRLMODE_FD; @@ -318,7 +319,7 @@ int can_change_mtu(struct net_device *dev, int new_mtu) case CANFD_MTU: /* check for potential CANFD ability */ if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD) && - !(priv->ctrlmode_static & CAN_CTRLMODE_FD)) + !(ctrlmode_static & CAN_CTRLMODE_FD)) return -EINVAL; priv->ctrlmode |= CAN_CTRLMODE_FD; diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c index 80425636049d..6c9906e8040c 100644 --- a/drivers/net/can/dev/netlink.c +++ b/drivers/net/can/dev/netlink.c @@ -112,7 +112,7 @@ static int can_changelink(struct net_device *dev, struct nlattr *tb[], if (dev->flags & IFF_UP) return -EBUSY; cm = nla_data(data[IFLA_CAN_CTRLMODE]); - ctrlstatic = priv->ctrlmode_static; + ctrlstatic = can_get_static_ctrlmode(priv); maskedflags = cm->flags & cm->mask; /* check whether provided bits are allowed to be passed */ diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 2413253e54c7..2381ad9e0814 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -69,7 +69,6 @@ struct can_priv { /* CAN controller features - see include/uapi/linux/can/netlink.h */ u32 ctrlmode; /* current options setting */ u32 ctrlmode_supported; /* options that can be modified by netlink */ - u32 ctrlmode_static; /* static enabled options for driver/hardware */ int restart_ms; struct delayed_work restart_work; @@ -104,14 +103,23 @@ static inline void can_set_static_ctrlmode(struct net_device *dev, struct can_priv *priv = netdev_priv(dev); /* alloc_candev() succeeded => netdev_priv() is valid at this point */ + if (priv->ctrlmode_supported & static_mode) { + netdev_warn(dev, + "Controller features can not be supported and static at the same time\n"); + return; + } priv->ctrlmode = static_mode; - priv->ctrlmode_static = static_mode; /* override MTU which was set by default in can_setup()? */ if (static_mode & CAN_CTRLMODE_FD) dev->mtu = CANFD_MTU; } +static inline u32 can_get_static_ctrlmode(struct can_priv *priv) +{ + return priv->ctrlmode & ~priv->ctrlmode_supported; +} + void can_setup(struct net_device *dev); struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max, From patchwork Sat Oct 9 13:13:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Mailhol X-Patchwork-Id: 12547691 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 519C4C433F5 for ; Sat, 9 Oct 2021 13:15:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3035E60F70 for ; Sat, 9 Oct 2021 13:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233386AbhJINRL (ORCPT ); Sat, 9 Oct 2021 09:17:11 -0400 Received: from smtp03.smtpout.orange.fr ([80.12.242.125]:50282 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233207AbhJINP1 (ORCPT ); Sat, 9 Oct 2021 09:15:27 -0400 Received: from tomoyo.flets-east.jp ([114.149.34.46]) by smtp.orange.fr with ESMTPA id ZC9zmoEn4UGqlZCAKm2if7; Sat, 09 Oct 2021 15:13:30 +0200 X-ME-Helo: tomoyo.flets-east.jp X-ME-Auth: MDU0YmViZGZmMDIzYiBlMiM2NTczNTRjNWZkZTMwOGRiOGQ4ODf3NWI1ZTMyMzdiODlhOQ== X-ME-Date: Sat, 09 Oct 2021 15:13:30 +0200 X-ME-IP: 114.149.34.46 From: Vincent Mailhol To: Marc Kleine-Budde , linux-can@vger.kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Vincent Mailhol Subject: [PATCH v2 2/3] can: dev: reorder struct can_priv members for better packing Date: Sat, 9 Oct 2021 22:13:03 +0900 Message-Id: <20211009131304.19729-3-mailhol.vincent@wanadoo.fr> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211009131304.19729-1-mailhol.vincent@wanadoo.fr> References: <20211009131304.19729-1-mailhol.vincent@wanadoo.fr> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Save eight bytes of holes on x86-64 architectures by reordering the members of struct can_priv. 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 */ | 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 6 bytes hole, try to pack */ | | struct gpio_desc * termination_gpio; /* 184 8 */ | /* --- cacheline 3 boundary (192 bytes) --- */ | u16 termination_gpio_ohms[2]; /* 192 4 */ | enum can_state state; /* 196 4 */ | u32 ctrlmode; /* 200 4 */ | u32 ctrlmode_supported; /* 204 4 */ | int restart_ms; /* 208 4 */ | | /* XXX 4 bytes hole, try to pack */ | | struct delayed_work restart_work; /* 216 88 */ | | /* XXX last struct has 4 bytes of padding */ | | /* --- cacheline 4 boundary (256 bytes) was 48 bytes ago --- */ | int (*do_set_bittiming)(struct net_device *); /* 304 8 */ | int (*do_set_data_bittiming)(struct net_device *); /* 312 8 */ | /* --- cacheline 5 boundary (320 bytes) --- */ | int (*do_set_mode)(struct net_device *, enum can_mode); /* 320 8 */ | int (*do_set_termination)(struct net_device *, u16); /* 328 8 */ | int (*do_get_state)(const struct net_device *, enum can_state *); /* 336 8 */ | int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 344 8 */ | unsigned int echo_skb_max; /* 352 4 */ | | /* XXX 4 bytes hole, try to pack */ | | struct sk_buff * * echo_skb; /* 360 8 */ | | /* size: 368, cachelines: 6, members: 32 */ | /* sum members: 354, holes: 3, sum holes: 14 */ | /* paddings: 1, sum paddings: 4 */ | /* last cacheline: 48 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 6 bytes hole, try to pack */ | | struct gpio_desc * termination_gpio; /* 184 8 */ | /* --- cacheline 3 boundary (192 bytes) --- */ | u16 termination_gpio_ohms[2]; /* 192 4 */ | unsigned int echo_skb_max; /* 196 4 */ | struct sk_buff * * echo_skb; /* 200 8 */ | enum can_state state; /* 208 4 */ | u32 ctrlmode; /* 212 4 */ | u32 ctrlmode_supported; /* 216 4 */ | int restart_ms; /* 220 4 */ | struct delayed_work restart_work; /* 224 88 */ | | /* XXX last struct has 4 bytes of padding */ | | /* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */ | int (*do_set_bittiming)(struct net_device *); /* 312 8 */ | /* --- cacheline 5 boundary (320 bytes) --- */ | int (*do_set_data_bittiming)(struct net_device *); /* 320 8 */ | int (*do_set_mode)(struct net_device *, enum can_mode); /* 328 8 */ | int (*do_set_termination)(struct net_device *, u16); /* 336 8 */ | int (*do_get_state)(const struct net_device *, enum can_state *); /* 344 8 */ | int (*do_get_berr_counter)(const struct net_device *, struct can_berr_counter *); /* 352 8 */ | | /* size: 360, cachelines: 6, members: 32 */ | /* sum members: 354, holes: 1, sum holes: 6 */ | /* paddings: 1, sum paddings: 4 */ | /* last cacheline: 40 bytes */ | }; Signed-off-by: Vincent Mailhol --- include/linux/can/dev.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h index 2381ad9e0814..78e49b1e001c 100644 --- a/include/linux/can/dev.h +++ b/include/linux/can/dev.h @@ -64,6 +64,9 @@ struct can_priv { struct gpio_desc *termination_gpio; u16 termination_gpio_ohms[CAN_TERMINATION_GPIO_MAX]; + unsigned int echo_skb_max; + struct sk_buff **echo_skb; + enum can_state state; /* CAN controller features - see include/uapi/linux/can/netlink.h */ @@ -82,9 +85,6 @@ struct can_priv { int (*do_get_berr_counter)(const struct net_device *dev, struct can_berr_counter *bec); - unsigned int echo_skb_max; - struct sk_buff **echo_skb; - #ifdef CONFIG_CAN_LEDS struct led_trigger *tx_led_trig; char tx_led_trig_name[CAN_LED_NAME_SZ]; From patchwork Sat Oct 9 13:13:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vincent Mailhol X-Patchwork-Id: 12547689 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A03AC433FE for ; Sat, 9 Oct 2021 13:15:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E9DC60F5A for ; Sat, 9 Oct 2021 13:15:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233652AbhJINRN (ORCPT ); Sat, 9 Oct 2021 09:17:13 -0400 Received: from smtp03.smtpout.orange.fr ([80.12.242.125]:57407 "EHLO smtp.smtpout.orange.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233661AbhJINPf (ORCPT ); Sat, 9 Oct 2021 09:15:35 -0400 Received: from tomoyo.flets-east.jp ([114.149.34.46]) by smtp.orange.fr with ESMTPA id ZC9zmoEn4UGqlZCARm2ihC; Sat, 09 Oct 2021 15:13:37 +0200 X-ME-Helo: tomoyo.flets-east.jp X-ME-Auth: MDU0YmViZGZmMDIzYiBlMiM2NTczNTRjNWZkZTMwOGRiOGQ4ODf3NWI1ZTMyMzdiODlhOQ== X-ME-Date: Sat, 09 Oct 2021 15:13:37 +0200 X-ME-IP: 114.149.34.46 From: Vincent Mailhol To: Marc Kleine-Budde , linux-can@vger.kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Vincent Mailhol Subject: [PATCH v2 3/3] can: netlink: report the CAN controller mode supported flags Date: Sat, 9 Oct 2021 22:13:04 +0900 Message-Id: <20211009131304.19729-4-mailhol.vincent@wanadoo.fr> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20211009131304.19729-1-mailhol.vincent@wanadoo.fr> References: <20211009131304.19729-1-mailhol.vincent@wanadoo.fr> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org This patch introduces a method for the user to check both the supported and the static capabilities. The proposed method reuses the existing struct can_ctrlmode and thus do not need a new IFLA_CAN_* entry. Currently, the CAN netlink interface provides no easy ways to check the capabilities of a given controller. The only method from the command line is to try each CAN_CTRLMODE_ individually to check whether the netlink interface returns an -EOPNOTSUPP error or not (alternatively, one may find it easier to directly check the source code of the driver instead...) It appears that, can_ctrlmode::mask is only used in one direction: from the userland to the kernel. So we can just reuse this field in the other direction (from the kernel to userland). But, because the semantic is different, we use a union to give this field a proper name: supported. Below table explains how the two fields can_ctrlmode::supported and can_ctrlmode::flags, when masked with any of the CAN_CTRLMODE_* bit flags, allow us to identify both the supported and the static capabilities: supported & flags & Controller capabilities CAN_CTRLMODE_* CAN_CTRLMODE_* ----------------------------------------------------------------------- false false Feature not supported (always disabled) false true Static feature (always enabled) true false Feature supported but disabled true true Feature supported and enabled Signed-off-by: Vincent Mailhol --- Please refer to below link for the iproute2-next counterpart of this patch: https://lore.kernel.org/linux-can/20211003050147.569044-1-mailhol.vincent@wanadoo.fr/T/#t --- drivers/net/can/dev/netlink.c | 5 ++++- include/uapi/linux/can/netlink.h | 5 ++++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c index 6c9906e8040c..86521836fd6d 100644 --- a/drivers/net/can/dev/netlink.c +++ b/drivers/net/can/dev/netlink.c @@ -264,7 +264,10 @@ static size_t can_get_size(const struct net_device *dev) static int can_fill_info(struct sk_buff *skb, const struct net_device *dev) { struct can_priv *priv = netdev_priv(dev); - struct can_ctrlmode cm = {.flags = priv->ctrlmode}; + struct can_ctrlmode cm = { + .supported = priv->ctrlmode_supported, + .flags = priv->ctrlmode + }; struct can_berr_counter bec = { }; enum can_state state = priv->state; diff --git a/include/uapi/linux/can/netlink.h b/include/uapi/linux/can/netlink.h index f730d443b918..2847ed0dcac3 100644 --- a/include/uapi/linux/can/netlink.h +++ b/include/uapi/linux/can/netlink.h @@ -88,7 +88,10 @@ struct can_berr_counter { * CAN controller mode */ struct can_ctrlmode { - __u32 mask; + union { + __u32 mask; /* Userland to kernel */ + __u32 supported; /* Kernel to userland */ + }; __u32 flags; };