diff mbox series

[net-next,4/6] can: netlink: avoid call to do_set_data_bittiming callback with stale can_priv::ctrlmode

Message ID 20240830214406.1605786-5-mkl@pengutronix.de (mailing list archive)
State Accepted
Commit 2423cc20087ae9a7b7af575aa62304ef67cad7b6
Delegated to: Netdev Maintainers
Headers show
Series [net-next,1/6] dt-bindings: can: renesas,rcar-canfd: Document R-Car V4M support | expand

Checks

Context Check Description
netdev/series_format success Pull request is its own cover letter
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 16 this patch: 16
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 4 maintainers not CCed: pabeni@redhat.com mailhol.vincent@wanadoo.fr maxime.jayat@mobile-devices.fr edumazet@google.com
netdev/build_clang success Errors and warnings before: 16 this patch: 16
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 16 this patch: 16
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 126 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2024-08-31--15-00 (tests: 714)

Commit Message

Marc Kleine-Budde Aug. 30, 2024, 9:34 p.m. UTC 
From: Stefan Mätje <stefan.maetje@esd.eu>

This patch moves the evaluation of data[IFLA_CAN_CTRLMODE] in function
can_changelink in front of the evaluation of data[IFLA_CAN_BITTIMING].

This avoids a call to do_set_data_bittiming providing a stale
can_priv::ctrlmode with a CAN_CTRLMODE_FD flag not matching the
requested state when switching between a CAN Classic and CAN-FD bitrate.

In the same manner the evaluation of data[IFLA_CAN_CTRLMODE] in function
can_validate is also moved in front of the evaluation of
data[IFLA_CAN_BITTIMING].

This is a preparation for patches where the nominal and data bittiming
may have interdependencies on the driver side depending on the
CAN_CTRLMODE_FD flag state.

Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu>
Link: https://patch.msgid.link/20240808164224.213522-1-stefan.maetje@esd.eu
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/dev/netlink.c | 102 +++++++++++++++++-----------------
 1 file changed, 51 insertions(+), 51 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/can/dev/netlink.c b/drivers/net/can/dev/netlink.c
index dfdc039d92a6..01aacdcda260 100644
--- a/drivers/net/can/dev/netlink.c
+++ b/drivers/net/can/dev/netlink.c
@@ -65,15 +65,6 @@  static int can_validate(struct nlattr *tb[], struct nlattr *data[],
 	if (!data)
 		return 0;
 
-	if (data[IFLA_CAN_BITTIMING]) {
-		struct can_bittiming bt;
-
-		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
-		err = can_validate_bittiming(&bt, extack);
-		if (err)
-			return err;
-	}
-
 	if (data[IFLA_CAN_CTRLMODE]) {
 		struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
 		u32 tdc_flags = cm->flags & CAN_CTRLMODE_TDC_MASK;
@@ -114,6 +105,15 @@  static int can_validate(struct nlattr *tb[], struct nlattr *data[],
 		}
 	}
 
+	if (data[IFLA_CAN_BITTIMING]) {
+		struct can_bittiming bt;
+
+		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
+		err = can_validate_bittiming(&bt, extack);
+		if (err)
+			return err;
+	}
+
 	if (is_can_fd) {
 		if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
 			return -EOPNOTSUPP;
@@ -195,48 +195,6 @@  static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 	/* We need synchronization with dev->stop() */
 	ASSERT_RTNL();
 
-	if (data[IFLA_CAN_BITTIMING]) {
-		struct can_bittiming bt;
-
-		/* Do not allow changing bittiming while running */
-		if (dev->flags & IFF_UP)
-			return -EBUSY;
-
-		/* Calculate bittiming parameters based on
-		 * bittiming_const if set, otherwise pass bitrate
-		 * directly via do_set_bitrate(). Bail out if neither
-		 * is given.
-		 */
-		if (!priv->bittiming_const && !priv->do_set_bittiming &&
-		    !priv->bitrate_const)
-			return -EOPNOTSUPP;
-
-		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
-		err = can_get_bittiming(dev, &bt,
-					priv->bittiming_const,
-					priv->bitrate_const,
-					priv->bitrate_const_cnt,
-					extack);
-		if (err)
-			return err;
-
-		if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
-			NL_SET_ERR_MSG_FMT(extack,
-					   "arbitration bitrate %u bps surpasses transceiver capabilities of %u bps",
-					   bt.bitrate, priv->bitrate_max);
-			return -EINVAL;
-		}
-
-		memcpy(&priv->bittiming, &bt, sizeof(bt));
-
-		if (priv->do_set_bittiming) {
-			/* Finally, set the bit-timing registers */
-			err = priv->do_set_bittiming(dev);
-			if (err)
-				return err;
-		}
-	}
-
 	if (data[IFLA_CAN_CTRLMODE]) {
 		struct can_ctrlmode *cm;
 		u32 ctrlstatic;
@@ -284,6 +242,48 @@  static int can_changelink(struct net_device *dev, struct nlattr *tb[],
 			priv->ctrlmode &= cm->flags | ~CAN_CTRLMODE_TDC_MASK;
 	}
 
+	if (data[IFLA_CAN_BITTIMING]) {
+		struct can_bittiming bt;
+
+		/* Do not allow changing bittiming while running */
+		if (dev->flags & IFF_UP)
+			return -EBUSY;
+
+		/* Calculate bittiming parameters based on
+		 * bittiming_const if set, otherwise pass bitrate
+		 * directly via do_set_bitrate(). Bail out if neither
+		 * is given.
+		 */
+		if (!priv->bittiming_const && !priv->do_set_bittiming &&
+		    !priv->bitrate_const)
+			return -EOPNOTSUPP;
+
+		memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
+		err = can_get_bittiming(dev, &bt,
+					priv->bittiming_const,
+					priv->bitrate_const,
+					priv->bitrate_const_cnt,
+					extack);
+		if (err)
+			return err;
+
+		if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
+			NL_SET_ERR_MSG_FMT(extack,
+					   "arbitration bitrate %u bps surpasses transceiver capabilities of %u bps",
+					   bt.bitrate, priv->bitrate_max);
+			return -EINVAL;
+		}
+
+		memcpy(&priv->bittiming, &bt, sizeof(bt));
+
+		if (priv->do_set_bittiming) {
+			/* Finally, set the bit-timing registers */
+			err = priv->do_set_bittiming(dev);
+			if (err)
+				return err;
+		}
+	}
+
 	if (data[IFLA_CAN_RESTART_MS]) {
 		/* Do not allow changing restart delay while running */
 		if (dev->flags & IFF_UP)