linux/net/sched/sch_mqprio_lib.c
Vladimir Oltean 9dd6ad674c net/sched: refactor mqprio qopt reconstruction to a library function
The taprio qdisc will need to reconstruct a struct tc_mqprio_qopt from
netdev settings once more in a future patch, but this code was already
written twice, once in taprio and once in mqprio.

Refactor the code to a helper in the common mqprio library.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-06 10:06:44 +00:00

118 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/netlink.h>
#include <linux/types.h>
#include <net/pkt_sched.h>
#include "sch_mqprio_lib.h"
/* Returns true if the intervals [a, b) and [c, d) overlap. */
static bool intervals_overlap(int a, int b, int c, int d)
{
int left = max(a, c), right = min(b, d);
return left < right;
}
static int mqprio_validate_queue_counts(struct net_device *dev,
const struct tc_mqprio_qopt *qopt,
bool allow_overlapping_txqs,
struct netlink_ext_ack *extack)
{
int i, j;
for (i = 0; i < qopt->num_tc; i++) {
unsigned int last = qopt->offset[i] + qopt->count[i];
if (!qopt->count[i]) {
NL_SET_ERR_MSG_FMT_MOD(extack, "No queues for TC %d",
i);
return -EINVAL;
}
/* Verify the queue count is in tx range being equal to the
* real_num_tx_queues indicates the last queue is in use.
*/
if (qopt->offset[i] >= dev->real_num_tx_queues ||
last > dev->real_num_tx_queues) {
NL_SET_ERR_MSG_FMT_MOD(extack,
"Queues %d:%d for TC %d exceed the %d TX queues available",
qopt->count[i], qopt->offset[i],
i, dev->real_num_tx_queues);
return -EINVAL;
}
if (allow_overlapping_txqs)
continue;
/* Verify that the offset and counts do not overlap */
for (j = i + 1; j < qopt->num_tc; j++) {
if (intervals_overlap(qopt->offset[i], last,
qopt->offset[j],
qopt->offset[j] +
qopt->count[j])) {
NL_SET_ERR_MSG_FMT_MOD(extack,
"TC %d queues %d@%d overlap with TC %d queues %d@%d",
i, qopt->count[i], qopt->offset[i],
j, qopt->count[j], qopt->offset[j]);
return -EINVAL;
}
}
}
return 0;
}
int mqprio_validate_qopt(struct net_device *dev, struct tc_mqprio_qopt *qopt,
bool validate_queue_counts,
bool allow_overlapping_txqs,
struct netlink_ext_ack *extack)
{
int i, err;
/* Verify num_tc is not out of max range */
if (qopt->num_tc > TC_MAX_QUEUE) {
NL_SET_ERR_MSG(extack,
"Number of traffic classes is outside valid range");
return -EINVAL;
}
/* Verify priority mapping uses valid tcs */
for (i = 0; i <= TC_BITMASK; i++) {
if (qopt->prio_tc_map[i] >= qopt->num_tc) {
NL_SET_ERR_MSG(extack,
"Invalid traffic class in priority to traffic class mapping");
return -EINVAL;
}
}
if (validate_queue_counts) {
err = mqprio_validate_queue_counts(dev, qopt,
allow_overlapping_txqs,
extack);
if (err)
return err;
}
return 0;
}
EXPORT_SYMBOL_GPL(mqprio_validate_qopt);
void mqprio_qopt_reconstruct(struct net_device *dev, struct tc_mqprio_qopt *qopt)
{
int tc, num_tc = netdev_get_num_tc(dev);
qopt->num_tc = num_tc;
memcpy(qopt->prio_tc_map, dev->prio_tc_map, sizeof(qopt->prio_tc_map));
for (tc = 0; tc < num_tc; tc++) {
qopt->count[tc] = dev->tc_to_txq[tc].count;
qopt->offset[tc] = dev->tc_to_txq[tc].offset;
}
}
EXPORT_SYMBOL_GPL(mqprio_qopt_reconstruct);
MODULE_LICENSE("GPL");