12 files changed, 181 insertions, 18 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-net-queues b/Documentation/ABI/testing/sysfs-class-net-queues
index 5e9aeb91d355..0c0df91b1516 100644
--- a/Documentation/ABI/testing/sysfs-class-net-queues
+++ b/Documentation/ABI/testing/sysfs-class-net-queues
@@ -24,6 +24,14 @@ Description:
                 Indicates the number of transmit timeout events seen by this
                 network interface transmit queue.
 
+What:           /sys/class/<iface>/queues/tx-<queue>/tx_maxrate
+Date:           March 2015
+KernelVersion:  4.1
+Contact:        netdev@vger.kernel.org
+Description:
+                A Mbps max-rate set for the queue, a value of zero means disabled,
+                default is disabled.
+
 What:           /sys/class/<iface>/queues/tx-<queue>/xps_cpus
 Date:           November 2010
 KernelVersion:  2.6.38
diff --git a/Documentation/networking/scaling.txt b/Documentation/networking/scaling.txt
index 99ca40e8e810..cbfac0949635 100644
--- a/Documentation/networking/scaling.txt
+++ b/Documentation/networking/scaling.txt
@@ -421,6 +421,15 @@ best CPUs to share a given queue are probably those that share the cache
 with the CPU that processes transmit completions for that queue
 (transmit interrupts).
 
+Per TX Queue rate limitation:
+=============================
+
+These are rate-limitation mechanisms implemented by HW, where currently
+a max-rate attribute is supported, by setting a Mbps value to
+
+/sys/class/net/<dev>/queues/tx-<n>/tx_maxrate
+
+A value of zero means disabled, and this is the default.
 
 Further Information
 ===================
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index c59ed925adaf..d8dc3f985c2b 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2379,6 +2379,33 @@ static netdev_features_t mlx4_en_features_check(struct sk_buff *skb,
 }
 #endif
 
+int mlx4_en_set_tx_maxrate(struct net_device *dev, int queue_index, u32 maxrate)
+{
+        struct mlx4_en_priv *priv = netdev_priv(dev);
+        struct mlx4_en_tx_ring *tx_ring = priv->tx_ring[queue_index];
+        struct mlx4_update_qp_params params;
+        int err;
+
+        if (!(priv->mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT))
+                return -EOPNOTSUPP;
+
+        /* rate provided to us in Mbs, check if it fits into 12 bits, if not use Gbs */
+        if (maxrate >> 12) {
+                params.rate_unit = MLX4_QP_RATE_LIMIT_GBS;
+                params.rate_val  = maxrate / 1000;
+        } else if (maxrate) {
+                params.rate_unit = MLX4_QP_RATE_LIMIT_MBS;
+                params.rate_val  = maxrate;
+        } else { /* zero serves to revoke the QP rate-limitation */
+                params.rate_unit = 0;
+                params.rate_val  = 0;
+        }
+
+        err = mlx4_update_qp(priv->mdev->dev, tx_ring->qpn, MLX4_UPDATE_QP_RATE_LIMIT,
+                             &params);
+        return err;
+}
+
 static const struct net_device_ops mlx4_netdev_ops = {
         .ndo_open               = mlx4_en_open,
         .ndo_stop               = mlx4_en_close,
@@ -2410,6 +2437,7 @@ static const struct net_device_ops mlx4_netdev_ops = {
         .ndo_del_vxlan_port     = mlx4_en_del_vxlan_port,
         .ndo_features_check     = mlx4_en_features_check,
 #endif
+        .ndo_set_tx_maxrate     = mlx4_en_set_tx_maxrate,
 };
 
 static const struct net_device_ops mlx4_netdev_ops_master = {
@@ -2444,6 +2472,7 @@ static const struct net_device_ops mlx4_netdev_ops_master = {
         .ndo_del_vxlan_port     = mlx4_en_del_vxlan_port,
         .ndo_features_check     = mlx4_en_features_check,
 #endif
+        .ndo_set_tx_maxrate     = mlx4_en_set_tx_maxrate,
 };
 
 struct mlx4_en_bond {
diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.c b/drivers/net/ethernet/mellanox/mlx4/fw.c
index 242bcee5d774..4a471f5d1b56 100644
--- a/drivers/net/ethernet/mellanox/mlx4/fw.c
+++ b/drivers/net/ethernet/mellanox/mlx4/fw.c
@@ -144,7 +144,8 @@ static void dump_dev_cap_flags2(struct mlx4_dev *dev, u64 flags)
                 [19] = "Performance optimized for limited rule configuration flow steering support",
                 [20] = "Recoverable error events support",
                 [21] = "Port Remap support",
-                [22] = "QCN support"
+                [22] = "QCN support",
+                [23] = "QP rate limiting support"
         };
         int i;
 
@@ -697,6 +698,10 @@ int mlx4_QUERY_DEV_CAP(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 #define QUERY_DEV_CAP_MAD_DEMUX_OFFSET          0xb0
 #define QUERY_DEV_CAP_DMFS_HIGH_RATE_QPN_BASE_OFFSET    0xa8
 #define QUERY_DEV_CAP_DMFS_HIGH_RATE_QPN_RANGE_OFFSET   0xac
+#define QUERY_DEV_CAP_QP_RATE_LIMIT_NUM_OFFSET  0xcc
+#define QUERY_DEV_CAP_QP_RATE_LIMIT_MAX_OFFSET  0xd0
+#define QUERY_DEV_CAP_QP_RATE_LIMIT_MIN_OFFSET  0xd2
+
 
         dev_cap->flags2 = 0;
         mailbox = mlx4_alloc_cmd_mailbox(dev);
@@ -904,6 +909,18 @@ int mlx4_QUERY_DEV_CAP(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
                  QUERY_DEV_CAP_DMFS_HIGH_RATE_QPN_RANGE_OFFSET);
         dev_cap->dmfs_high_rate_qpn_range &= MGM_QPN_MASK;
 
+        MLX4_GET(size, outbox, QUERY_DEV_CAP_QP_RATE_LIMIT_NUM_OFFSET);
+        dev_cap->rl_caps.num_rates = size;
+        if (dev_cap->rl_caps.num_rates) {
+                dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT;
+                MLX4_GET(size, outbox, QUERY_DEV_CAP_QP_RATE_LIMIT_MAX_OFFSET);
+                dev_cap->rl_caps.max_val  = size & 0xfff;
+                dev_cap->rl_caps.max_unit = size >> 14;
+                MLX4_GET(size, outbox, QUERY_DEV_CAP_QP_RATE_LIMIT_MIN_OFFSET);
+                dev_cap->rl_caps.min_val  = size & 0xfff;
+                dev_cap->rl_caps.min_unit = size >> 14;
+        }
+
         MLX4_GET(field32, outbox, QUERY_DEV_CAP_EXT_2_FLAGS_OFFSET);
         if (field32 & (1 << 16))
                 dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_UPDATE_QP;
@@ -979,6 +996,15 @@ void mlx4_dev_cap_dump(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
                  dev_cap->dmfs_high_rate_qpn_base);
         mlx4_dbg(dev, "DMFS high rate steer QPn range: %d\n",
                  dev_cap->dmfs_high_rate_qpn_range);
+
+        if (dev_cap->flags2 & MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT) {
+                struct mlx4_rate_limit_caps *rl_caps = &dev_cap->rl_caps;
+
+                mlx4_dbg(dev, "QP Rate-Limit: #rates %d, unit/val max %d/%d, min %d/%d\n",
+                         rl_caps->num_rates, rl_caps->max_unit, rl_caps->max_val,
+                         rl_caps->min_unit, rl_caps->min_val);
+        }
+
         dump_dev_cap_flags(dev, dev_cap->flags);
         dump_dev_cap_flags2(dev, dev_cap->flags2);
 }
@@ -1075,6 +1101,7 @@ int mlx4_QUERY_DEV_CAP_wrapper(struct mlx4_dev *dev, int slave,
         u64     flags;
         int     err = 0;
         u8      field;
+        u16     field16;
         u32     bmme_flags, field32;
         int     real_port;
         int     slave_port;
@@ -1158,6 +1185,10 @@ int mlx4_QUERY_DEV_CAP_wrapper(struct mlx4_dev *dev, int slave,
         field &= 0xfe;
         MLX4_PUT(outbox->buf, field, QUERY_DEV_CAP_ECN_QCN_VER_OFFSET);
 
+        /* turn off QP max-rate limiting for guests */
+        field16 = 0;
+        MLX4_PUT(outbox->buf, field16, QUERY_DEV_CAP_QP_RATE_LIMIT_NUM_OFFSET);
+
         return 0;
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.h b/drivers/net/ethernet/mellanox/mlx4/fw.h
index f44f7f6017ed..863655bd3947 100644
--- a/drivers/net/ethernet/mellanox/mlx4/fw.h
+++ b/drivers/net/ethernet/mellanox/mlx4/fw.h
@@ -127,6 +127,7 @@ struct mlx4_dev_cap {
         u32 max_counters;
         u32 dmfs_high_rate_qpn_base;
         u32 dmfs_high_rate_qpn_range;
+        struct mlx4_rate_limit_caps rl_caps;
         struct mlx4_port_cap port_cap[MLX4_MAX_PORTS + 1];
 };
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 7e487223489a..43aa76775b5f 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -489,6 +489,8 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
                 dev->caps.dmfs_high_rate_qpn_range = MLX4_A0_STEERING_TABLE_SIZE;
         }
 
+        dev->caps.rl_caps = dev_cap->rl_caps;
+
         dev->caps.reserved_qps_cnt[MLX4_QP_REGION_RSS_RAW_ETH] =
                 dev->caps.dmfs_high_rate_qpn_range;
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/qp.c b/drivers/net/ethernet/mellanox/mlx4/qp.c
index eda29dbbfcd2..69e4462e4ee4 100644
--- a/drivers/net/ethernet/mellanox/mlx4/qp.c
+++ b/drivers/net/ethernet/mellanox/mlx4/qp.c
@@ -442,6 +442,11 @@ int mlx4_update_qp(struct mlx4_dev *dev, u32 qpn,
                         cmd->qp_context.param3 |= cpu_to_be32(MLX4_STRIP_VLAN);
         }
 
+        if (attr & MLX4_UPDATE_QP_RATE_LIMIT) {
+                qp_mask |= 1ULL << MLX4_UPD_QP_MASK_RATE_LIMIT;
+                cmd->qp_context.rate_limit_params = cpu_to_be16((params->rate_unit << 14) | params->rate_val);
+        }
+
         cmd->primary_addr_path_mask = cpu_to_be64(pri_addr_path_mask);
         cmd->qp_mask = cpu_to_be64(qp_mask);
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
index d43e25914d19..c258f8625aac 100644
--- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
+++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
@@ -2947,8 +2947,12 @@ static int verify_qp_parameters(struct mlx4_dev *dev,
         qp_type = (be32_to_cpu(qp_ctx->flags) >> 16) & 0xff;
         optpar  = be32_to_cpu(*(__be32 *) inbox->buf);
 
-        if (slave != mlx4_master_func_num(dev))
+        if (slave != mlx4_master_func_num(dev)) {
                 qp_ctx->params2 &= ~MLX4_QP_BIT_FPP;
+                /* setting QP rate-limit is disallowed for VFs */
+                if (qp_ctx->rate_limit_params)
+                        return -EPERM;
+        }
 
         switch (qp_type) {
         case MLX4_QP_ST_RC:
diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 1cc54822b931..4550c67b92e4 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -205,6 +205,7 @@ enum {
         MLX4_DEV_CAP_FLAG2_RECOVERABLE_ERROR_EVENT = 1LL << 20,
         MLX4_DEV_CAP_FLAG2_PORT_REMAP           = 1LL <<  21,
         MLX4_DEV_CAP_FLAG2_QCN                  = 1LL <<  22,
+        MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT        = 1LL <<  23
 };
 
 enum {
@@ -450,6 +451,21 @@ enum mlx4_module_id {
         MLX4_MODULE_ID_QSFP28           = 0x11,
 };
 
+enum { /* rl */
+        MLX4_QP_RATE_LIMIT_NONE         = 0,
+        MLX4_QP_RATE_LIMIT_KBS          = 1,
+        MLX4_QP_RATE_LIMIT_MBS          = 2,
+        MLX4_QP_RATE_LIMIT_GBS          = 3
+};
+
+struct mlx4_rate_limit_caps {
+        u16     num_rates; /* Number of different rates */
+        u8      min_unit;
+        u16     min_val;
+        u8      max_unit;
+        u16     max_val;
+};
+
 static inline u64 mlx4_fw_ver(u64 major, u64 minor, u64 subminor)
 {
         return (major << 32) | (minor << 16) | subminor;
@@ -565,6 +581,7 @@ struct mlx4_caps {
         u32                     dmfs_high_rate_qpn_base;
         u32                     dmfs_high_rate_qpn_range;
         u32                     vf_caps;
+        struct mlx4_rate_limit_caps rl_caps;
 };
 
 struct mlx4_buf_list {
diff --git a/include/linux/mlx4/qp.h b/include/linux/mlx4/qp.h
index 551f85456c11..1023ebe035b7 100644
--- a/include/linux/mlx4/qp.h
+++ b/include/linux/mlx4/qp.h
@@ -207,14 +207,16 @@ struct mlx4_qp_context {
         __be32                  msn;
         __be16                  rq_wqe_counter;
         __be16                  sq_wqe_counter;
-        u32                     reserved3[2];
+        u32                     reserved3;
+        __be16                  rate_limit_params;
+        __be16                  reserved4;
         __be32                  param3;
         __be32                  nummmcpeers_basemkey;
         u8                      log_page_size;
-        u8                      reserved4[2];
+        u8                      reserved5[2];
         u8                      mtt_base_addr_h;
         __be32                  mtt_base_addr_l;
-        u32                     reserved5[10];
+        u32                     reserved6[10];
 };
 
 struct mlx4_update_qp_context {
@@ -229,6 +231,7 @@ struct mlx4_update_qp_context {
 enum {
         MLX4_UPD_QP_MASK_PM_STATE       = 32,
         MLX4_UPD_QP_MASK_VSD            = 33,
+        MLX4_UPD_QP_MASK_RATE_LIMIT     = 35,
 };
 
 enum {
@@ -428,7 +431,8 @@ struct mlx4_wqe_inline_seg {
 enum mlx4_update_qp_attr {
         MLX4_UPDATE_QP_SMAC             = 1 << 0,
         MLX4_UPDATE_QP_VSD              = 1 << 1,
-        MLX4_UPDATE_QP_SUPPORTED_ATTRS  = (1 << 2) - 1
+        MLX4_UPDATE_QP_RATE_LIMIT       = 1 << 2,
+        MLX4_UPDATE_QP_SUPPORTED_ATTRS  = (1 << 3) - 1
 };
 
 enum mlx4_update_qp_params_flags {
@@ -438,6 +442,8 @@ enum mlx4_update_qp_params_flags {
 struct mlx4_update_qp_params {
         u8      smac_index;
         u32     flags;
+        u16     rate_unit;
+        u16     rate_val;
 };
 
 int mlx4_update_qp(struct mlx4_dev *dev, u32 qpn,
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index dd1d069758be..76c5de4978a8 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -587,6 +587,7 @@ struct netdev_queue {
 #ifdef CONFIG_BQL
         struct dql              dql;
 #endif
+        unsigned long           tx_maxrate;
 } ____cacheline_aligned_in_smp;
 
 static inline int netdev_queue_numa_node_read(const struct netdev_queue *q)
@@ -1022,6 +1023,10 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
  *      be otherwise expressed by feature flags. The check is called with
  *      the set of features that the stack has calculated and it returns
  *      those the driver believes to be appropriate.
+ * int (*ndo_set_tx_maxrate)(struct net_device *dev,
+ *                           int queue_index, u32 maxrate);
+ *      Called when a user wants to set a max-rate limitation of specific
+ *      TX queue.
  */
 struct net_device_ops {
         int                     (*ndo_init)(struct net_device *dev);
@@ -1178,6 +1183,9 @@ struct net_device_ops {
         netdev_features_t       (*ndo_features_check) (struct sk_buff *skb,
                                                        struct net_device *dev,
                                                        netdev_features_t features);
+        int                     (*ndo_set_tx_maxrate)(struct net_device *dev,
+                                                      int queue_index,
+                                                      u32 maxrate);
 };
 
 /**
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index cf30620a88e1..7e58bd7ec232 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -951,6 +951,60 @@ static ssize_t show_trans_timeout(struct netdev_queue *queue,
         return sprintf(buf, "%lu", trans_timeout);
 }
 
+#ifdef CONFIG_XPS
+static inline unsigned int get_netdev_queue_index(struct netdev_queue *queue)
+{
+        struct net_device *dev = queue->dev;
+        int i;
+
+        for (i = 0; i < dev->num_tx_queues; i++)
+                if (queue == &dev->_tx[i])
+                        break;
+
+        BUG_ON(i >= dev->num_tx_queues);
+
+        return i;
+}
+
+static ssize_t show_tx_maxrate(struct netdev_queue *queue,
+                               struct netdev_queue_attribute *attribute,
+                               char *buf)
+{
+        return sprintf(buf, "%lu\n", queue->tx_maxrate);
+}
+
+static ssize_t set_tx_maxrate(struct netdev_queue *queue,
+                              struct netdev_queue_attribute *attribute,
+                              const char *buf, size_t len)
+{
+        struct net_device *dev = queue->dev;
+        int err, index = get_netdev_queue_index(queue);
+        u32 rate = 0;
+
+        err = kstrtou32(buf, 10, &rate);
+        if (err < 0)
+                return err;
+
+        if (!rtnl_trylock())
+                return restart_syscall();
+
+        err = -EOPNOTSUPP;
+        if (dev->netdev_ops->ndo_set_tx_maxrate)
+                err = dev->netdev_ops->ndo_set_tx_maxrate(dev, index, rate);
+
+        rtnl_unlock();
+        if (!err) {
+                queue->tx_maxrate = rate;
+                return len;
+        }
+        return err;
+}
+
+static struct netdev_queue_attribute queue_tx_maxrate =
+        __ATTR(tx_maxrate, S_IRUGO | S_IWUSR,
+               show_tx_maxrate, set_tx_maxrate);
+#endif
+
 static struct netdev_queue_attribute queue_trans_timeout =
         __ATTR(tx_timeout, S_IRUGO, show_trans_timeout, NULL);
 
@@ -1065,18 +1119,6 @@ static struct attribute_group dql_group = {
 #endif /* CONFIG_BQL */
 
 #ifdef CONFIG_XPS
-static unsigned int get_netdev_queue_index(struct netdev_queue *queue)
-{
-        struct net_device *dev = queue->dev;
-        unsigned int i;
-
-        i = queue - dev->_tx;
-        BUG_ON(i >= dev->num_tx_queues);
-
-        return i;
-}
-
-
 static ssize_t show_xps_map(struct netdev_queue *queue,
                             struct netdev_queue_attribute *attribute, char *buf)
 {
@@ -1153,6 +1195,7 @@ static struct attribute *netdev_queue_default_attrs[] = {
         &queue_trans_timeout.attr,
 #ifdef CONFIG_XPS
         &xps_cpus_attribute.attr,
+        &queue_tx_maxrate.attr,
 #endif
         NULL
 };