drivers/net/ethernet/google/gve/gve_utils.c

   1 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
   2 /* Google virtual Ethernet (gve) driver
   3  *
   4  * Copyright (C) 2015-2021 Google, Inc.
   5  */
   6
   7 #include "gve.h"
   8 #include "gve_adminq.h"
   9 #include "gve_utils.h"
  10
  11 bool gve_tx_was_added_to_block(struct gve_priv *priv, int queue_idx)
  12 {
  13         struct gve_notify_block *block =
  14                         &priv->ntfy_blocks[gve_tx_idx_to_ntfy(priv, queue_idx)];
  15
  16         return block->tx != NULL;
  17 }
  18
  19 void gve_tx_remove_from_block(struct gve_priv *priv, int queue_idx)
  20 {
  21         struct gve_notify_block *block =
  22                         &priv->ntfy_blocks[gve_tx_idx_to_ntfy(priv, queue_idx)];
  23
  24         block->tx = NULL;
  25 }
  26
  27 void gve_tx_add_to_block(struct gve_priv *priv, int queue_idx)
  28 {
  29         unsigned int active_cpus = min_t(int, priv->num_ntfy_blks / 2,
  30                                          num_online_cpus());
  31         int ntfy_idx = gve_tx_idx_to_ntfy(priv, queue_idx);
  32         struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
  33         struct gve_tx_ring *tx = &priv->tx[queue_idx];
  34
  35         block->tx = tx;
  36         tx->ntfy_id = ntfy_idx;
  37         netif_set_xps_queue(priv->dev, get_cpu_mask(ntfy_idx % active_cpus),
  38                             queue_idx);
  39 }
  40
  41 bool gve_rx_was_added_to_block(struct gve_priv *priv, int queue_idx)
  42 {
  43         struct gve_notify_block *block =
  44                         &priv->ntfy_blocks[gve_rx_idx_to_ntfy(priv, queue_idx)];
  45
  46         return block->rx != NULL;
  47 }
  48
  49 void gve_rx_remove_from_block(struct gve_priv *priv, int queue_idx)
  50 {
  51         struct gve_notify_block *block =
  52                         &priv->ntfy_blocks[gve_rx_idx_to_ntfy(priv, queue_idx)];
  53
  54         block->rx = NULL;
  55 }
  56
  57 void gve_rx_add_to_block(struct gve_priv *priv, int queue_idx)
  58 {
  59         u32 ntfy_idx = gve_rx_idx_to_ntfy(priv, queue_idx);
  60         struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
  61         struct gve_rx_ring *rx = &priv->rx[queue_idx];
  62
  63         block->rx = rx;
  64         rx->ntfy_id = ntfy_idx;
  65 }
  66
  67 struct sk_buff *gve_rx_copy_data(struct net_device *dev, struct napi_struct *napi,
  68                                  u8 *data, u16 len)
  69 {
  70         struct sk_buff *skb;
  71
  72         skb = napi_alloc_skb(napi, len);
  73         if (unlikely(!skb))
  74                 return NULL;
  75
  76         __skb_put(skb, len);
  77         skb_copy_to_linear_data_offset(skb, 0, data, len);
  78         skb->protocol = eth_type_trans(skb, dev);
  79
  80         return skb;
  81 }
  82
  83 struct sk_buff *gve_rx_copy(struct net_device *dev, struct napi_struct *napi,
  84                             struct gve_rx_slot_page_info *page_info, u16 len)
  85 {
  86         void *va = page_info->page_address + page_info->page_offset +
  87                 page_info->pad;
  88
  89         return gve_rx_copy_data(dev, napi, va, len);
  90 }
  91
  92 void gve_dec_pagecnt_bias(struct gve_rx_slot_page_info *page_info)
  93 {
  94         page_info->pagecnt_bias--;
  95         if (page_info->pagecnt_bias == 0) {
  96                 int pagecount = page_count(page_info->page);
  97
  98                 /* If we have run out of bias - set it back up to INT_MAX
  99                  * minus the existing refs.
 100                  */
 101                 page_info->pagecnt_bias = INT_MAX - pagecount;
 102
 103                 /* Set pagecount back up to max. */
 104                 page_ref_add(page_info->page, INT_MAX - pagecount);
 105         }
 106 }
 107
 108 void gve_add_napi(struct gve_priv *priv, int ntfy_idx,
 109                   int (*gve_poll)(struct napi_struct *, int))
 110 {
 111         struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
 112
 113         netif_napi_add(priv->dev, &block->napi, gve_poll);
 114 }
 115
 116 void gve_remove_napi(struct gve_priv *priv, int ntfy_idx)
 117 {
 118         struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
 119
 120         netif_napi_del(&block->napi);
 121 }