// SPDX-License-Identifier: (GPL-2.0 OR MIT)
/* Google virtual Ethernet (gve) driver
 *
 * Copyright (C) 2015-2021 Google, Inc.
 */

#include "gve.h"
#include "gve_adminq.h"
#include "gve_utils.h"

bool gve_tx_was_added_to_block(struct gve_priv *priv, int queue_idx)
{
        struct gve_notify_block *block =
                        &priv->ntfy_blocks[gve_tx_idx_to_ntfy(priv, queue_idx)];

        return block->tx != NULL;
}

void gve_tx_remove_from_block(struct gve_priv *priv, int queue_idx)
{
        struct gve_notify_block *block =
                        &priv->ntfy_blocks[gve_tx_idx_to_ntfy(priv, queue_idx)];

        block->tx = NULL;
}

void gve_tx_add_to_block(struct gve_priv *priv, int queue_idx)
{
        unsigned int active_cpus = min_t(int, priv->num_ntfy_blks / 2,
                                         num_online_cpus());
        int ntfy_idx = gve_tx_idx_to_ntfy(priv, queue_idx);
        struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
        struct gve_tx_ring *tx = &priv->tx[queue_idx];

        block->tx = tx;
        tx->ntfy_id = ntfy_idx;
        netif_set_xps_queue(priv->dev, get_cpu_mask(ntfy_idx % active_cpus),
                            queue_idx);
}

bool gve_rx_was_added_to_block(struct gve_priv *priv, int queue_idx)
{
        struct gve_notify_block *block =
                        &priv->ntfy_blocks[gve_rx_idx_to_ntfy(priv, queue_idx)];

        return block->rx != NULL;
}

void gve_rx_remove_from_block(struct gve_priv *priv, int queue_idx)
{
        struct gve_notify_block *block =
                        &priv->ntfy_blocks[gve_rx_idx_to_ntfy(priv, queue_idx)];

        block->rx = NULL;
}

void gve_rx_add_to_block(struct gve_priv *priv, int queue_idx)
{
        u32 ntfy_idx = gve_rx_idx_to_ntfy(priv, queue_idx);
        struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];
        struct gve_rx_ring *rx = &priv->rx[queue_idx];

        block->rx = rx;
        rx->ntfy_id = ntfy_idx;
}

struct sk_buff *gve_rx_copy_data(struct net_device *dev, struct napi_struct *napi,
                                 u8 *data, u16 len)
{
        struct sk_buff *skb;

        skb = napi_alloc_skb(napi, len);
        if (unlikely(!skb))
                return NULL;

        __skb_put(skb, len);
        skb_copy_to_linear_data_offset(skb, 0, data, len);
        skb->protocol = eth_type_trans(skb, dev);

        return skb;
}

struct sk_buff *gve_rx_copy(struct net_device *dev, struct napi_struct *napi,
                            struct gve_rx_slot_page_info *page_info, u16 len)
{
        void *va = page_info->page_address + page_info->page_offset +
                page_info->pad;

        return gve_rx_copy_data(dev, napi, va, len);
}

void gve_dec_pagecnt_bias(struct gve_rx_slot_page_info *page_info)
{
        page_info->pagecnt_bias--;
        if (page_info->pagecnt_bias == 0) {
                int pagecount = page_count(page_info->page);

                /* If we have run out of bias - set it back up to INT_MAX
                 * minus the existing refs.
                 */
                page_info->pagecnt_bias = INT_MAX - pagecount;

                /* Set pagecount back up to max. */
                page_ref_add(page_info->page, INT_MAX - pagecount);
        }
}

void gve_add_napi(struct gve_priv *priv, int ntfy_idx,
                  int (*gve_poll)(struct napi_struct *, int))
{
        struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];

        netif_napi_add_locked(priv->dev, &block->napi, gve_poll);
        netif_napi_set_irq_locked(&block->napi, block->irq);
        enable_irq(block->irq);
}

void gve_remove_napi(struct gve_priv *priv, int ntfy_idx)
{
        struct gve_notify_block *block = &priv->ntfy_blocks[ntfy_idx];

        disable_irq(block->irq);
        netif_napi_del_locked(&block->napi);
}