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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-08 04:21:35 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-08 04:21:35 +0000
commit7b642cd94bb96385cbdbb36a1952f129af6b1bbb (patch)
treee7c4209372da8a2fa745aaa3e99d062e54d0f556 /drivers/net/can/rx-offload.c
parentAdding debian version 4.19.289-2. (diff)
downloadlinux-7b642cd94bb96385cbdbb36a1952f129af6b1bbb.tar.xz
linux-7b642cd94bb96385cbdbb36a1952f129af6b1bbb.zip
Merging upstream version 4.19.304.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/can/rx-offload.c')
-rw-r--r--drivers/net/can/rx-offload.c404
1 files changed, 0 insertions, 404 deletions
diff --git a/drivers/net/can/rx-offload.c b/drivers/net/can/rx-offload.c
deleted file mode 100644
index 5cf4171df..000000000
--- a/drivers/net/can/rx-offload.c
+++ /dev/null
@@ -1,404 +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 = (struct sk_buff *)head;
-
- 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;
- }
-
- __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;
-}
-
-/**
- * can_rx_offload_offload_one() - Read one CAN frame from HW
- * @offload: pointer to rx_offload context
- * @n: number of mailbox to read
- *
- * The task of this function is to read a CAN frame from mailbox @n
- * from the device and return the mailbox's content as a struct
- * sk_buff.
- *
- * If the struct can_rx_offload::skb_queue exceeds the maximal queue
- * length (struct can_rx_offload::skb_queue_len_max) or no skb can be
- * allocated, the mailbox contents is discarded by reading it into an
- * overflow buffer. This way the mailbox is marked as free by the
- * driver.
- *
- * Return: A pointer to skb containing the CAN frame on success.
- *
- * NULL if the mailbox @n is empty.
- *
- * ERR_PTR() in case of an error
- */
-static struct sk_buff *
-can_rx_offload_offload_one(struct can_rx_offload *offload, unsigned int n)
-{
- struct sk_buff *skb = NULL, *skb_error = NULL;
- struct can_rx_offload_cb *cb;
- struct can_frame *cf;
- int ret;
-
- if (likely(skb_queue_len(&offload->skb_queue) <
- offload->skb_queue_len_max)) {
- skb = alloc_can_skb(offload->dev, &cf);
- if (unlikely(!skb))
- skb_error = ERR_PTR(-ENOMEM); /* skb alloc failed */
- } else {
- skb_error = ERR_PTR(-ENOBUFS); /* skb_queue is full */
- }
-
- /* If queue is full or skb not available, drop by reading into
- * overflow buffer.
- */
- if (unlikely(skb_error)) {
- struct can_frame cf_overflow;
- u32 timestamp;
-
- ret = offload->mailbox_read(offload, &cf_overflow,
- &timestamp, n);
-
- /* Mailbox was empty. */
- if (unlikely(!ret))
- return NULL;
-
- /* Mailbox has been read and we're dropping it or
- * there was a problem reading the mailbox.
- *
- * Increment error counters in any case.
- */
- offload->dev->stats.rx_dropped++;
- offload->dev->stats.rx_fifo_errors++;
-
- /* There was a problem reading the mailbox, propagate
- * error value.
- */
- if (unlikely(ret < 0))
- return ERR_PTR(ret);
-
- return skb_error;
- }
-
- cb = can_rx_offload_get_cb(skb);
- ret = offload->mailbox_read(offload, cf, &cb->timestamp, n);
-
- /* Mailbox was empty. */
- if (unlikely(!ret)) {
- kfree_skb(skb);
- return NULL;
- }
-
- /* There was a problem reading the mailbox, propagate error value. */
- if (unlikely(ret < 0)) {
- kfree_skb(skb);
-
- offload->dev->stats.rx_dropped++;
- offload->dev->stats.rx_fifo_errors++;
-
- return ERR_PTR(ret);
- }
-
- /* Mailbox was read. */
- 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 (IS_ERR_OR_NULL(skb))
- continue;
-
- __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 (1) {
- skb = can_rx_offload_offload_one(offload, 0);
- if (IS_ERR(skb))
- continue;
- if (!skb)
- break;
-
- 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) {
- dev_kfree_skb_any(skb);
- return -ENOBUFS;
- }
-
- 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) {
- dev_kfree_skb_any(skb);
- return -ENOBUFS;
- }
-
- 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);