diff options
Diffstat (limited to 'drivers/net/can/rx-offload.c')
| -rw-r--r-- | drivers/net/can/rx-offload.c | 338 |
1 files changed, 0 insertions, 338 deletions
diff --git a/drivers/net/can/rx-offload.c b/drivers/net/can/rx-offload.c deleted file mode 100644 index 2ce4fa8698c7..000000000000 --- a/drivers/net/can/rx-offload.c +++ /dev/null @@ -1,338 +0,0 @@ -/* - * Copyright (c) 2014 David Jander, Protonic Holland - * Copyright (C) 2014-2017 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the version 2 of the GNU General Public License - * as published by the Free Software Foundation - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, see <http://www.gnu.org/licenses/>. - */ - -#include <linux/can/dev.h> -#include <linux/can/rx-offload.h> - -struct can_rx_offload_cb { - u32 timestamp; -}; - -static inline struct can_rx_offload_cb *can_rx_offload_get_cb(struct sk_buff *skb) -{ - BUILD_BUG_ON(sizeof(struct can_rx_offload_cb) > sizeof(skb->cb)); - - return (struct can_rx_offload_cb *)skb->cb; -} - -static inline bool can_rx_offload_le(struct can_rx_offload *offload, unsigned int a, unsigned int b) -{ - if (offload->inc) - return a <= b; - else - return a >= b; -} - -static inline unsigned int can_rx_offload_inc(struct can_rx_offload *offload, unsigned int *val) -{ - if (offload->inc) - return (*val)++; - else - return (*val)--; -} - -static int can_rx_offload_napi_poll(struct napi_struct *napi, int quota) -{ - struct can_rx_offload *offload = container_of(napi, struct can_rx_offload, napi); - struct net_device *dev = offload->dev; - struct net_device_stats *stats = &dev->stats; - struct sk_buff *skb; - int work_done = 0; - - while ((work_done < quota) && - (skb = skb_dequeue(&offload->skb_queue))) { - struct can_frame *cf = (struct can_frame *)skb->data; - - work_done++; - stats->rx_packets++; - stats->rx_bytes += cf->can_dlc; - netif_receive_skb(skb); - } - - if (work_done < quota) { - napi_complete_done(napi, work_done); - - /* Check if there was another interrupt */ - if (!skb_queue_empty(&offload->skb_queue)) - napi_reschedule(&offload->napi); - } - - can_led_event(offload->dev, CAN_LED_EVENT_RX); - - return work_done; -} - -static inline void __skb_queue_add_sort(struct sk_buff_head *head, struct sk_buff *new, - int (*compare)(struct sk_buff *a, struct sk_buff *b)) -{ - struct sk_buff *pos, *insert = NULL; - - skb_queue_reverse_walk(head, pos) { - const struct can_rx_offload_cb *cb_pos, *cb_new; - - cb_pos = can_rx_offload_get_cb(pos); - cb_new = can_rx_offload_get_cb(new); - - netdev_dbg(new->dev, - "%s: pos=0x%08x, new=0x%08x, diff=%10d, queue_len=%d\n", - __func__, - cb_pos->timestamp, cb_new->timestamp, - cb_new->timestamp - cb_pos->timestamp, - skb_queue_len(head)); - - if (compare(pos, new) < 0) - continue; - insert = pos; - break; - } - if (!insert) - __skb_queue_head(head, new); - else - __skb_queue_after(head, insert, new); -} - -static int can_rx_offload_compare(struct sk_buff *a, struct sk_buff *b) -{ - const struct can_rx_offload_cb *cb_a, *cb_b; - - cb_a = can_rx_offload_get_cb(a); - cb_b = can_rx_offload_get_cb(b); - - /* Substract two u32 and return result as int, to keep - * difference steady around the u32 overflow. - */ - return cb_b->timestamp - cb_a->timestamp; -} - -static struct sk_buff *can_rx_offload_offload_one(struct can_rx_offload *offload, unsigned int n) -{ - struct sk_buff *skb = NULL; - struct can_rx_offload_cb *cb; - struct can_frame *cf; - int ret; - - /* If queue is full or skb not available, read to discard mailbox */ - if (likely(skb_queue_len(&offload->skb_queue) <= - offload->skb_queue_len_max)) - skb = alloc_can_skb(offload->dev, &cf); - - if (!skb) { - struct can_frame cf_overflow; - u32 timestamp; - - ret = offload->mailbox_read(offload, &cf_overflow, - ×tamp, n); - if (ret) - offload->dev->stats.rx_dropped++; - - return NULL; - } - - cb = can_rx_offload_get_cb(skb); - ret = offload->mailbox_read(offload, cf, &cb->timestamp, n); - if (!ret) { - kfree_skb(skb); - return NULL; - } - - return skb; -} - -int can_rx_offload_irq_offload_timestamp(struct can_rx_offload *offload, u64 pending) -{ - struct sk_buff_head skb_queue; - unsigned int i; - - __skb_queue_head_init(&skb_queue); - - for (i = offload->mb_first; - can_rx_offload_le(offload, i, offload->mb_last); - can_rx_offload_inc(offload, &i)) { - struct sk_buff *skb; - - if (!(pending & BIT_ULL(i))) - continue; - - skb = can_rx_offload_offload_one(offload, i); - if (!skb) - break; - - __skb_queue_add_sort(&skb_queue, skb, can_rx_offload_compare); - } - - if (!skb_queue_empty(&skb_queue)) { - unsigned long flags; - u32 queue_len; - - spin_lock_irqsave(&offload->skb_queue.lock, flags); - skb_queue_splice_tail(&skb_queue, &offload->skb_queue); - spin_unlock_irqrestore(&offload->skb_queue.lock, flags); - - if ((queue_len = skb_queue_len(&offload->skb_queue)) > - (offload->skb_queue_len_max / 8)) - netdev_dbg(offload->dev, "%s: queue_len=%d\n", - __func__, queue_len); - - can_rx_offload_schedule(offload); - } - - return skb_queue_len(&skb_queue); -} -EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_timestamp); - -int can_rx_offload_irq_offload_fifo(struct can_rx_offload *offload) -{ - struct sk_buff *skb; - int received = 0; - - while ((skb = can_rx_offload_offload_one(offload, 0))) { - skb_queue_tail(&offload->skb_queue, skb); - received++; - } - - if (received) - can_rx_offload_schedule(offload); - - return received; -} -EXPORT_SYMBOL_GPL(can_rx_offload_irq_offload_fifo); - -int can_rx_offload_queue_sorted(struct can_rx_offload *offload, - struct sk_buff *skb, u32 timestamp) -{ - struct can_rx_offload_cb *cb; - unsigned long flags; - - if (skb_queue_len(&offload->skb_queue) > - offload->skb_queue_len_max) - return -ENOMEM; - - cb = can_rx_offload_get_cb(skb); - cb->timestamp = timestamp; - - spin_lock_irqsave(&offload->skb_queue.lock, flags); - __skb_queue_add_sort(&offload->skb_queue, skb, can_rx_offload_compare); - spin_unlock_irqrestore(&offload->skb_queue.lock, flags); - - can_rx_offload_schedule(offload); - - return 0; -} -EXPORT_SYMBOL_GPL(can_rx_offload_queue_sorted); - -unsigned int can_rx_offload_get_echo_skb(struct can_rx_offload *offload, - unsigned int idx, u32 timestamp) -{ - struct net_device *dev = offload->dev; - struct net_device_stats *stats = &dev->stats; - struct sk_buff *skb; - u8 len; - int err; - - skb = __can_get_echo_skb(dev, idx, &len); - if (!skb) - return 0; - - err = can_rx_offload_queue_sorted(offload, skb, timestamp); - if (err) { - stats->rx_errors++; - stats->tx_fifo_errors++; - } - - return len; -} -EXPORT_SYMBOL_GPL(can_rx_offload_get_echo_skb); - -int can_rx_offload_queue_tail(struct can_rx_offload *offload, - struct sk_buff *skb) -{ - if (skb_queue_len(&offload->skb_queue) > - offload->skb_queue_len_max) - return -ENOMEM; - - skb_queue_tail(&offload->skb_queue, skb); - can_rx_offload_schedule(offload); - - return 0; -} -EXPORT_SYMBOL_GPL(can_rx_offload_queue_tail); - -static int can_rx_offload_init_queue(struct net_device *dev, struct can_rx_offload *offload, unsigned int weight) -{ - offload->dev = dev; - - /* Limit queue len to 4x the weight (rounted to next power of two) */ - offload->skb_queue_len_max = 2 << fls(weight); - offload->skb_queue_len_max *= 4; - skb_queue_head_init(&offload->skb_queue); - - can_rx_offload_reset(offload); - netif_napi_add(dev, &offload->napi, can_rx_offload_napi_poll, weight); - - dev_dbg(dev->dev.parent, "%s: skb_queue_len_max=%d\n", - __func__, offload->skb_queue_len_max); - - return 0; -} - -int can_rx_offload_add_timestamp(struct net_device *dev, struct can_rx_offload *offload) -{ - unsigned int weight; - - if (offload->mb_first > BITS_PER_LONG_LONG || - offload->mb_last > BITS_PER_LONG_LONG || !offload->mailbox_read) - return -EINVAL; - - if (offload->mb_first < offload->mb_last) { - offload->inc = true; - weight = offload->mb_last - offload->mb_first; - } else { - offload->inc = false; - weight = offload->mb_first - offload->mb_last; - } - - return can_rx_offload_init_queue(dev, offload, weight); -} -EXPORT_SYMBOL_GPL(can_rx_offload_add_timestamp); - -int can_rx_offload_add_fifo(struct net_device *dev, struct can_rx_offload *offload, unsigned int weight) -{ - if (!offload->mailbox_read) - return -EINVAL; - - return can_rx_offload_init_queue(dev, offload, weight); -} -EXPORT_SYMBOL_GPL(can_rx_offload_add_fifo); - -void can_rx_offload_enable(struct can_rx_offload *offload) -{ - can_rx_offload_reset(offload); - napi_enable(&offload->napi); -} -EXPORT_SYMBOL_GPL(can_rx_offload_enable); - -void can_rx_offload_del(struct can_rx_offload *offload) -{ - netif_napi_del(&offload->napi); - skb_queue_purge(&offload->skb_queue); -} -EXPORT_SYMBOL_GPL(can_rx_offload_del); - -void can_rx_offload_reset(struct can_rx_offload *offload) -{ -} -EXPORT_SYMBOL_GPL(can_rx_offload_reset); |
