Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Handling of a master device, switching frames via its switch fabric CPU port
3 *
4 * Copyright (c) 2017 Savoir-faire Linux Inc.
5 * Vivien Didelot <vivien.didelot@savoirfairelinux.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13#include "dsa_priv.h"
14
15static void dsa_master_get_ethtool_stats(struct net_device *dev,
16 struct ethtool_stats *stats,
17 uint64_t *data)
18{
19 struct dsa_port *cpu_dp = dev->dsa_ptr;
20 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
21 struct dsa_switch *ds = cpu_dp->ds;
22 int port = cpu_dp->index;
23 int count = 0;
24
25 if (ops->get_sset_count && ops->get_ethtool_stats) {
26 count = ops->get_sset_count(dev, ETH_SS_STATS);
27 ops->get_ethtool_stats(dev, stats, data);
28 }
29
30 if (ds->ops->get_ethtool_stats)
31 ds->ops->get_ethtool_stats(ds, port, data + count);
32}
33
34static void dsa_master_get_ethtool_phy_stats(struct net_device *dev,
35 struct ethtool_stats *stats,
36 uint64_t *data)
37{
38 struct dsa_port *cpu_dp = dev->dsa_ptr;
39 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
40 struct dsa_switch *ds = cpu_dp->ds;
41 int port = cpu_dp->index;
42 int count = 0;
43
44 if (dev->phydev && !ops->get_ethtool_phy_stats) {
45 count = phy_ethtool_get_sset_count(dev->phydev);
46 if (count >= 0)
47 phy_ethtool_get_stats(dev->phydev, stats, data);
48 } else if (ops->get_sset_count && ops->get_ethtool_phy_stats) {
49 count = ops->get_sset_count(dev, ETH_SS_PHY_STATS);
50 ops->get_ethtool_phy_stats(dev, stats, data);
51 }
52
53 if (count < 0)
54 count = 0;
55
56 if (ds->ops->get_ethtool_phy_stats)
57 ds->ops->get_ethtool_phy_stats(ds, port, data + count);
58}
59
60static int dsa_master_get_sset_count(struct net_device *dev, int sset)
61{
62 struct dsa_port *cpu_dp = dev->dsa_ptr;
63 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
64 struct dsa_switch *ds = cpu_dp->ds;
65 int count = 0;
66
67 if (sset == ETH_SS_PHY_STATS && dev->phydev &&
68 !ops->get_ethtool_phy_stats)
69 count = phy_ethtool_get_sset_count(dev->phydev);
70 else if (ops->get_sset_count)
71 count = ops->get_sset_count(dev, sset);
72
73 if (count < 0)
74 count = 0;
75
76 if (ds->ops->get_sset_count)
77 count += ds->ops->get_sset_count(ds, cpu_dp->index, sset);
78
79 return count;
80}
81
82static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
83 uint8_t *data)
84{
85 struct dsa_port *cpu_dp = dev->dsa_ptr;
86 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
87 struct dsa_switch *ds = cpu_dp->ds;
88 int port = cpu_dp->index;
89 int len = ETH_GSTRING_LEN;
90 int mcount = 0, count;
91 unsigned int i;
92 uint8_t pfx[4];
93 uint8_t *ndata;
94
95 snprintf(pfx, sizeof(pfx), "p%.2d", port);
96 /* We do not want to be NULL-terminated, since this is a prefix */
97 pfx[sizeof(pfx) - 1] = '_';
98
99 if (stringset == ETH_SS_PHY_STATS && dev->phydev &&
100 !ops->get_ethtool_phy_stats) {
101 mcount = phy_ethtool_get_sset_count(dev->phydev);
102 if (mcount < 0)
103 mcount = 0;
104 else
105 phy_ethtool_get_strings(dev->phydev, data);
106 } else if (ops->get_sset_count && ops->get_strings) {
107 mcount = ops->get_sset_count(dev, stringset);
108 if (mcount < 0)
109 mcount = 0;
110 ops->get_strings(dev, stringset, data);
111 }
112
113 if (ds->ops->get_strings) {
114 ndata = data + mcount * len;
115 /* This function copies ETH_GSTRINGS_LEN bytes, we will mangle
116 * the output after to prepend our CPU port prefix we
117 * constructed earlier
118 */
119 ds->ops->get_strings(ds, port, stringset, ndata);
120 count = ds->ops->get_sset_count(ds, port, stringset);
121 for (i = 0; i < count; i++) {
122 memmove(ndata + (i * len + sizeof(pfx)),
123 ndata + i * len, len - sizeof(pfx));
124 memcpy(ndata + i * len, pfx, sizeof(pfx));
125 }
126 }
127}
128
129static int dsa_master_ethtool_setup(struct net_device *dev)
130{
131 struct dsa_port *cpu_dp = dev->dsa_ptr;
132 struct dsa_switch *ds = cpu_dp->ds;
133 struct ethtool_ops *ops;
134
135 ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
136 if (!ops)
137 return -ENOMEM;
138
139 cpu_dp->orig_ethtool_ops = dev->ethtool_ops;
140 if (cpu_dp->orig_ethtool_ops)
141 memcpy(ops, cpu_dp->orig_ethtool_ops, sizeof(*ops));
142
143 ops->get_sset_count = dsa_master_get_sset_count;
144 ops->get_ethtool_stats = dsa_master_get_ethtool_stats;
145 ops->get_strings = dsa_master_get_strings;
146 ops->get_ethtool_phy_stats = dsa_master_get_ethtool_phy_stats;
147
148 dev->ethtool_ops = ops;
149
150 return 0;
151}
152
153static void dsa_master_ethtool_teardown(struct net_device *dev)
154{
155 struct dsa_port *cpu_dp = dev->dsa_ptr;
156
157 dev->ethtool_ops = cpu_dp->orig_ethtool_ops;
158 cpu_dp->orig_ethtool_ops = NULL;
159}
160
161static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
162 char *buf)
163{
164 struct net_device *dev = to_net_dev(d);
165 struct dsa_port *cpu_dp = dev->dsa_ptr;
166
167 return sprintf(buf, "%s\n",
168 dsa_tag_protocol_to_str(cpu_dp->tag_ops));
169}
170static DEVICE_ATTR_RO(tagging);
171
172static struct attribute *dsa_slave_attrs[] = {
173 &dev_attr_tagging.attr,
174 NULL
175};
176
177static const struct attribute_group dsa_group = {
178 .name = "dsa",
179 .attrs = dsa_slave_attrs,
180};
181
182static void dsa_master_set_mtu(struct net_device *dev, struct dsa_port *cpu_dp)
183{
184 unsigned int mtu = ETH_DATA_LEN + cpu_dp->tag_ops->overhead;
185 int err;
186
187 rtnl_lock();
188 if (mtu <= dev->max_mtu) {
189 err = dev_set_mtu(dev, mtu);
190 if (err)
191 netdev_dbg(dev, "Unable to set MTU to include for DSA overheads\n");
192 }
193 rtnl_unlock();
194}
195
196static void dsa_master_reset_mtu(struct net_device *dev)
197{
198 int err;
199
200 rtnl_lock();
201 err = dev_set_mtu(dev, ETH_DATA_LEN);
202 if (err)
203 netdev_dbg(dev,
204 "Unable to reset MTU to exclude DSA overheads\n");
205 rtnl_unlock();
206}
207
208int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
209{
210 int ret;
211
212 dsa_master_set_mtu(dev, cpu_dp);
213
214 /* If we use a tagging format that doesn't have an ethertype
215 * field, make sure that all packets from this point on get
216 * sent to the tag format's receive function.
217 */
218 wmb();
219
220 dev->dsa_ptr = cpu_dp;
221
222 ret = dsa_master_ethtool_setup(dev);
223 if (ret)
224 return ret;
225
226 ret = sysfs_create_group(&dev->dev.kobj, &dsa_group);
227 if (ret)
228 dsa_master_ethtool_teardown(dev);
229
230 return ret;
231}
232
233void dsa_master_teardown(struct net_device *dev)
234{
235 sysfs_remove_group(&dev->dev.kobj, &dsa_group);
236 dsa_master_ethtool_teardown(dev);
237 dsa_master_reset_mtu(dev);
238
239 dev->dsa_ptr = NULL;
240
241 /* If we used a tagging format that doesn't have an ethertype
242 * field, make sure that all packets from this point get sent
243 * without the tag and go through the regular receive path.
244 */
245 wmb();
246}