diff mbox series

[v4,net-next,10/15] net: enetc: request mqprio to validate the queue counts

Message ID 20230130173145.475943-11-vladimir.oltean@nxp.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series ENETC mqprio/taprio cleanup | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/cc_maintainers success CCed 6 of 6 maintainers
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
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: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 26 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Vladimir Oltean Jan. 30, 2023, 5:31 p.m. UTC 
The enetc driver does not validate the mqprio queue configuration, so it
currently allows things like this:

$ tc qdisc add dev swp0 root handle 1: mqprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 queues 3@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 1

By requesting validation via the mqprio capability structure, this is no
longer allowed, and needs no custom code in the driver.

The check that num_tc <= real_num_tx_queues also becomes superfluous and
can be dropped, because mqprio_validate_queue_counts() validates that no
TXQ range exceeds real_num_tx_queues. That is a stronger check, because
there is at least 1 TXQ per TC, so there are at least as many TXQs as TCs.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
---
v2->v4: none
v1->v2: move the deletion of the num_tc check to this patch, and add an
        explanation for it

 drivers/net/ethernet/freescale/enetc/enetc.c     | 7 -------
 drivers/net/ethernet/freescale/enetc/enetc_qos.c | 7 +++++++
 2 files changed, 7 insertions(+), 7 deletions(-)

Comments

Simon Horman Feb. 1, 2023, 2:12 p.m. UTC | #1 
On Mon, Jan 30, 2023 at 07:31:40PM +0200, Vladimir Oltean wrote:
> The enetc driver does not validate the mqprio queue configuration, so it
> currently allows things like this:
> 
> $ tc qdisc add dev swp0 root handle 1: mqprio num_tc 8 \
> 	map 0 1 2 3 4 5 6 7 queues 3@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 1
> 
> By requesting validation via the mqprio capability structure, this is no
> longer allowed, and needs no custom code in the driver.
> 
> The check that num_tc <= real_num_tx_queues also becomes superfluous and
> can be dropped, because mqprio_validate_queue_counts() validates that no
> TXQ range exceeds real_num_tx_queues. That is a stronger check, because
> there is at least 1 TXQ per TC, so there are at least as many TXQs as TCs.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>

Reviewed-by: Simon Horman <simon.horman@corigine.com>
diff mbox series

Patch

diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c
index 1c0aeaa13cde..e4718b50cf31 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc.c
@@ -2638,13 +2638,6 @@  int enetc_setup_tc_mqprio(struct net_device *ndev, void *type_data)
 		return 0;
 	}
 
-	/* Check if we have enough BD rings available to accommodate all TCs */
-	if (num_tc > num_stack_tx_queues) {
-		netdev_err(ndev, "Max %d traffic classes supported\n",
-			   priv->num_tx_rings);
-		return -EINVAL;
-	}
-
 	/* For the moment, we use only one BD ring per TC.
 	 *
 	 * Configure num_tc BD rings with increasing priorities.
diff --git a/drivers/net/ethernet/freescale/enetc/enetc_qos.c b/drivers/net/ethernet/freescale/enetc/enetc_qos.c
index fcebb54224c0..6e0b4dd91509 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_qos.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_qos.c
@@ -1611,6 +1611,13 @@  int enetc_qos_query_caps(struct net_device *ndev, void *type_data)
 	struct enetc_si *si = priv->si;
 
 	switch (base->type) {
+	case TC_SETUP_QDISC_MQPRIO: {
+		struct tc_mqprio_caps *caps = base->caps;
+
+		caps->validate_queue_counts = true;
+
+		return 0;
+	}
 	case TC_SETUP_QDISC_TAPRIO: {
 		struct tc_taprio_caps *caps = base->caps;