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
 11bool 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
 19void 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
 27void 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
 41bool 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
 49void 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
 57void 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
 67struct 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
 83struct 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
 92void 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
108void 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
116void 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}