summaryrefslogtreecommitdiff
path: root/net/sched/sch_mqprio_lib.c
blob: b3a5572c167b719f96e2947fa4267f1f93077814 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
// 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);

void mqprio_fp_to_offload(u32 fp[TC_QOPT_MAX_QUEUE],
			  struct tc_mqprio_qopt_offload *mqprio)
{
	unsigned long preemptible_tcs = 0;
	int tc;

	for (tc = 0; tc < TC_QOPT_MAX_QUEUE; tc++)
		if (fp[tc] == TC_FP_PREEMPTIBLE)
			preemptible_tcs |= BIT(tc);

	mqprio->preemptible_tcs = preemptible_tcs;
}
EXPORT_SYMBOL_GPL(mqprio_fp_to_offload);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Shared mqprio qdisc code currently between taprio and mqprio");