From: Avinash Dayanand <avinash.dayanand@intel.com>
Date: Thu, 13 Feb 2020 13:30:59 -0800
Subject: ice: Validate config for SW DCB map
Patch-mainline: v5.7-rc1
Git-commit: a29a912d448dbc9912705377195bf6418da5897f
References: jsc#SLE-12878

Validate the inputs for SW DCB config received either via lldptool or pcap
file. And don't apply DCB for bad bandwidth inputs. Without this patch, any
config having bad inputs will cause the loss of link making PF unusable
even after driver reload. Recoverable only via system reboot.

Signed-off-by: Avinash Dayanand <avinash.dayanand@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/ice/ice_dcb_lib.c |   40 +++++++++++++++++++++++++++
 drivers/net/ethernet/intel/ice/ice_dcb_lib.h |    1 
 drivers/net/ethernet/intel/ice/ice_dcb_nl.c  |    6 ++++
 3 files changed, 47 insertions(+)

--- a/drivers/net/ethernet/intel/ice/ice_dcb_lib.c
+++ b/drivers/net/ethernet/intel/ice/ice_dcb_lib.c
@@ -149,6 +149,43 @@ void ice_vsi_cfg_dcb_rings(struct ice_vs
 }
 
 /**
+ * ice_dcb_bwchk - check if ETS bandwidth input parameters are correct
+ * @pf: pointer to the PF struct
+ * @dcbcfg: pointer to DCB config structure
+ */
+int ice_dcb_bwchk(struct ice_pf *pf, struct ice_dcbx_cfg *dcbcfg)
+{
+	struct ice_dcb_ets_cfg *etscfg = &dcbcfg->etscfg;
+	u8 num_tc, total_bw = 0;
+	int i;
+
+	/* returns number of contigous TCs and 1 TC for non-contigous TCs,
+	 * since at least 1 TC has to be configured
+	 */
+	num_tc = ice_dcb_get_num_tc(dcbcfg);
+
+	/* no bandwidth checks required if there's only one TC, so assign
+	 * all bandwidth to TC0 and return
+	 */
+	if (num_tc == 1) {
+		etscfg->tcbwtable[0] = ICE_TC_MAX_BW;
+		return 0;
+	}
+
+	for (i = 0; i < num_tc; i++)
+		total_bw += etscfg->tcbwtable[i];
+
+	if (!total_bw) {
+		etscfg->tcbwtable[0] = ICE_TC_MAX_BW;
+	} else if (total_bw != ICE_TC_MAX_BW) {
+		dev_err(ice_pf_to_dev(pf), "Invalid config, total bandwidth must equal 100\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/**
  * ice_pf_dcb_cfg - Apply new DCB configuration
  * @pf: pointer to the PF struct
  * @new_cfg: DCBX config to apply
@@ -182,6 +219,9 @@ int ice_pf_dcb_cfg(struct ice_pf *pf, st
 		return ret;
 	}
 
+	if (ice_dcb_bwchk(pf, new_cfg))
+		return -EINVAL;
+
 	/* Store old config in case FW config fails */
 	old_cfg = kmemdup(curr_cfg, sizeof(*old_cfg), GFP_KERNEL);
 	if (!old_cfg)
--- a/drivers/net/ethernet/intel/ice/ice_dcb_lib.h
+++ b/drivers/net/ethernet/intel/ice/ice_dcb_lib.h
@@ -20,6 +20,7 @@ u8 ice_dcb_get_num_tc(struct ice_dcbx_cf
 u8 ice_dcb_get_tc(struct ice_vsi *vsi, int queue_index);
 int
 ice_pf_dcb_cfg(struct ice_pf *pf, struct ice_dcbx_cfg *new_cfg, bool locked);
+int ice_dcb_bwchk(struct ice_pf *pf, struct ice_dcbx_cfg *dcbcfg);
 void ice_pf_dcb_recfg(struct ice_pf *pf);
 void ice_vsi_cfg_dcb_rings(struct ice_vsi *vsi);
 int ice_init_pf_dcb(struct ice_pf *pf, bool locked);
--- a/drivers/net/ethernet/intel/ice/ice_dcb_nl.c
+++ b/drivers/net/ethernet/intel/ice/ice_dcb_nl.c
@@ -95,6 +95,11 @@ static int ice_dcbnl_setets(struct net_d
 		new_cfg->etsrec.prio_table[i] = ets->reco_prio_tc[i];
 	}
 
+	if (ice_dcb_bwchk(pf, new_cfg)) {
+		err = -EINVAL;
+		goto ets_out;
+	}
+
 	/* max_tc is a 1-8 value count of number of TC's, not a 0-7 value
 	 * for the TC's index number.  Add one to value if not zero, and
 	 * for zero set it to the FW's default value
@@ -119,6 +124,7 @@ static int ice_dcbnl_setets(struct net_d
 	if (err == ICE_DCB_NO_HW_CHG)
 		err = ICE_DCB_HW_CHG_RST;
 
+ets_out:
 	mutex_unlock(&pf->tc_mutex);
 	return err;
 }