[PATCH 5.4 149/389] iavf: Fix max_rate limiting

Greg Kroah-Hartman
2022-08-23T11:27:44Z

From: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>

[ Upstream commit ec60d54cb9a3d43a02c5612a03093c18233e6601 ]

Fix max_rate option in TC, check for proper quanta boundaries.
Check for minimum value provided and if it fits expected 50Mbps
quanta.

Without this patch, iavf could send settings for max_rate limiting
that would be accepted from by PF even the max_rate option is less
than expected 50Mbps quanta. It results in no rate limiting
on traffic as rate limiting will be floored to 0.

Example:
tc qdisc add dev $vf root mqprio num_tc 3 map 0 2 1 queues \
2@0 2@2 2@4 hw 1 mode channel shaper bw_rlimit \
max_rate 50Mbps 500Mbps 500Mbps

Should limit TC0 to circa 50 Mbps

tc qdisc add dev $vf root mqprio num_tc 3 map 0 2 1 queues \
2@0 2@2 2@4 hw 1 mode channel shaper bw_rlimit \
max_rate 0Mbps 100Kbit 500Mbps

Should return error

Fixes: d5b33d024496 ("i40evf: add ndo_setup_tc callback to i40evf")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Jun Zhang <xuejun.zhang@intel.com>
Tested-by: Bharathi Sreenivas <bharathi.sreenivas@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/intel/iavf/iavf.h | 1 +
drivers/net/ethernet/intel/iavf/iavf_main.c | 25 +++++++++++++++++++--
2 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/intel/iavf/iavf.h b/drivers/net/ethernet/intel/iavf/iavf.h
index 81ca6472937d..85275b6ede4d 100644
--- a/drivers/net/ethernet/intel/iavf/iavf.h
+++ b/drivers/net/ethernet/intel/iavf/iavf.h
@@ -86,6 +86,7 @@ struct iavf_vsi {
#define IAVF_HKEY_ARRAY_SIZE ((IAVF_VFQF_HKEY_MAX_INDEX + 1) * 4)
#define IAVF_HLUT_ARRAY_SIZE ((IAVF_VFQF_HLUT_MAX_INDEX + 1) * 4)
#define IAVF_MBPS_DIVISOR 125000 /* divisor to convert to Mbps */
+#define IAVF_MBPS_QUANTA 50

#define IAVF_VIRTCHNL_VF_RESOURCE_SIZE (sizeof(struct virtchnl_vf_resource) + \
(IAVF_MAX_VF_VSI * \
diff --git a/drivers/net/ethernet/intel/iavf/iavf_main.c b/drivers/net/ethernet/intel/iavf/iavf_main.c
index e8850ba5604c..4c41bb47fc1a 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_main.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_main.c
@@ -2581,6 +2581,7 @@ static int iavf_validate_ch_config(struct iavf_adapter *adapter,
struct tc_mqprio_qopt_offload *mqprio_qopt)
{
u64 total_max_rate = 0;
+ u32 tx_rate_rem = 0;
int i, num_qps = 0;
u64 tx_rate = 0;
int ret = 0;
@@ -2595,12 +2596,32 @@ static int iavf_validate_ch_config(struct iavf_adapter *adapter,
return -EINVAL;
if (mqprio_qopt->min_rate[i]) {
dev_err(&adapter->pdev->dev,
- "Invalid min tx rate (greater than 0) specified\n");
+ "Invalid min tx rate (greater than 0) specified for TC%d\n",
+ i);
return -EINVAL;
}
- /*convert to Mbps */
+
+ /* convert to Mbps */
tx_rate = div_u64(mqprio_qopt->max_rate[i],
IAVF_MBPS_DIVISOR);
+
+ if (mqprio_qopt->max_rate[i] &&
+ tx_rate < IAVF_MBPS_QUANTA) {
+ dev_err(&adapter->pdev->dev,
+ "Invalid max tx rate for TC%d, minimum %dMbps\n",
+ i, IAVF_MBPS_QUANTA);
+ return -EINVAL;
+ }
+
+ (void)div_u64_rem(tx_rate, IAVF_MBPS_QUANTA, &tx_rate_rem);
+
+ if (tx_rate_rem != 0) {
+ dev_err(&adapter->pdev->dev,
+ "Invalid max tx rate for TC%d, not divisible by %d\n",
+ i, IAVF_MBPS_QUANTA);
+ return -EINVAL;
+ }
+
total_max_rate += tx_rate;
num_qps += mqprio_qopt->qopt.count[i];
}
--
2.35.1