1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright Gavin Shan, IBM Corporation 2016. 4 */ 5 6 #include <linux/module.h> 7 #include <linux/kernel.h> 8 #include <linux/init.h> 9 #include <linux/netdevice.h> 10 #include <linux/skbuff.h> 11 12 #include <net/ncsi.h> 13 #include <net/net_namespace.h> 14 #include <net/sock.h> 15 16 #include "internal.h" 17 #include "ncsi-pkt.h" 18 19 static int ncsi_validate_aen_pkt(struct ncsi_aen_pkt_hdr *h, 20 const unsigned short payload) 21 { 22 u32 checksum; 23 __be32 *pchecksum; 24 25 if (h->common.revision != NCSI_PKT_REVISION) 26 return -EINVAL; 27 if (ntohs(h->common.length) != payload) 28 return -EINVAL; 29 30 /* Validate checksum, which might be zeroes if the 31 * sender doesn't support checksum according to NCSI 32 * specification. 33 */ 34 pchecksum = (__be32 *)((void *)(h + 1) + payload - 4); 35 if (ntohl(*pchecksum) == 0) 36 return 0; 37 38 checksum = ncsi_calculate_checksum((unsigned char *)h, 39 sizeof(*h) + payload - 4); 40 if (*pchecksum != htonl(checksum)) 41 return -EINVAL; 42 43 return 0; 44 } 45 46 static int ncsi_aen_handler_lsc(struct ncsi_dev_priv *ndp, 47 struct ncsi_aen_pkt_hdr *h) 48 { 49 struct ncsi_channel *nc, *tmp; 50 struct ncsi_channel_mode *ncm; 51 unsigned long old_data, data; 52 struct ncsi_aen_lsc_pkt *lsc; 53 struct ncsi_package *np; 54 bool had_link, has_link; 55 unsigned long flags; 56 bool chained; 57 int state; 58 59 /* Find the NCSI channel */ 60 ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc); 61 if (!nc) 62 return -ENODEV; 63 64 /* Update the link status */ 65 lsc = (struct ncsi_aen_lsc_pkt *)h; 66 67 spin_lock_irqsave(&nc->lock, flags); 68 ncm = &nc->modes[NCSI_MODE_LINK]; 69 old_data = ncm->data[2]; 70 data = ntohl(lsc->status); 71 ncm->data[2] = data; 72 ncm->data[4] = ntohl(lsc->oem_status); 73 74 had_link = !!(old_data & 0x1); 75 has_link = !!(data & 0x1); 76 77 netdev_dbg(ndp->ndev.dev, "NCSI: LSC AEN - channel %u state %s\n", 78 nc->id, data & 0x1 ? "up" : "down"); 79 80 chained = !list_empty(&nc->link); 81 state = nc->state; 82 spin_unlock_irqrestore(&nc->lock, flags); 83 84 if (state == NCSI_CHANNEL_INACTIVE) 85 netdev_warn(ndp->ndev.dev, 86 "NCSI: Inactive channel %u received AEN!\n", 87 nc->id); 88 89 if ((had_link == has_link) || chained) 90 return 0; 91 92 if (!ndp->multi_package && !nc->package->multi_channel) { 93 if (had_link) { 94 ndp->flags |= NCSI_DEV_RESHUFFLE; 95 ncsi_stop_channel_monitor(nc); 96 spin_lock_irqsave(&ndp->lock, flags); 97 list_add_tail_rcu(&nc->link, &ndp->channel_queue); 98 spin_unlock_irqrestore(&ndp->lock, flags); 99 return ncsi_process_next_channel(ndp); 100 } 101 /* Configured channel came up */ 102 return 0; 103 } 104 105 if (had_link) { 106 ncm = &nc->modes[NCSI_MODE_TX_ENABLE]; 107 if (ncsi_channel_is_last(ndp, nc)) { 108 /* No channels left, reconfigure */ 109 return ncsi_reset_dev(&ndp->ndev); 110 } else if (ncm->enable) { 111 /* Need to failover Tx channel */ 112 ncsi_update_tx_channel(ndp, nc->package, nc, NULL); 113 } 114 } else if (has_link && nc->package->preferred_channel == nc) { 115 /* Return Tx to preferred channel */ 116 ncsi_update_tx_channel(ndp, nc->package, NULL, nc); 117 } else if (has_link) { 118 NCSI_FOR_EACH_PACKAGE(ndp, np) { 119 NCSI_FOR_EACH_CHANNEL(np, tmp) { 120 /* Enable Tx on this channel if the current Tx 121 * channel is down. 122 */ 123 ncm = &tmp->modes[NCSI_MODE_TX_ENABLE]; 124 if (ncm->enable && 125 !ncsi_channel_has_link(tmp)) { 126 ncsi_update_tx_channel(ndp, nc->package, 127 tmp, nc); 128 break; 129 } 130 } 131 } 132 } 133 134 /* Leave configured channels active in a multi-channel scenario so 135 * AEN events are still received. 136 */ 137 return 0; 138 } 139 140 static int ncsi_aen_handler_cr(struct ncsi_dev_priv *ndp, 141 struct ncsi_aen_pkt_hdr *h) 142 { 143 struct ncsi_channel *nc; 144 unsigned long flags; 145 146 /* Find the NCSI channel */ 147 ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc); 148 if (!nc) 149 return -ENODEV; 150 151 spin_lock_irqsave(&nc->lock, flags); 152 if (!list_empty(&nc->link) || 153 nc->state != NCSI_CHANNEL_ACTIVE) { 154 spin_unlock_irqrestore(&nc->lock, flags); 155 return 0; 156 } 157 spin_unlock_irqrestore(&nc->lock, flags); 158 159 ncsi_stop_channel_monitor(nc); 160 spin_lock_irqsave(&nc->lock, flags); 161 nc->state = NCSI_CHANNEL_INVISIBLE; 162 spin_unlock_irqrestore(&nc->lock, flags); 163 164 spin_lock_irqsave(&ndp->lock, flags); 165 nc->state = NCSI_CHANNEL_INACTIVE; 166 list_add_tail_rcu(&nc->link, &ndp->channel_queue); 167 spin_unlock_irqrestore(&ndp->lock, flags); 168 nc->modes[NCSI_MODE_TX_ENABLE].enable = 0; 169 170 return ncsi_process_next_channel(ndp); 171 } 172 173 static int ncsi_aen_handler_hncdsc(struct ncsi_dev_priv *ndp, 174 struct ncsi_aen_pkt_hdr *h) 175 { 176 struct ncsi_channel *nc; 177 struct ncsi_channel_mode *ncm; 178 struct ncsi_aen_hncdsc_pkt *hncdsc; 179 unsigned long flags; 180 181 /* Find the NCSI channel */ 182 ncsi_find_package_and_channel(ndp, h->common.channel, NULL, &nc); 183 if (!nc) 184 return -ENODEV; 185 186 spin_lock_irqsave(&nc->lock, flags); 187 ncm = &nc->modes[NCSI_MODE_LINK]; 188 hncdsc = (struct ncsi_aen_hncdsc_pkt *)h; 189 ncm->data[3] = ntohl(hncdsc->status); 190 spin_unlock_irqrestore(&nc->lock, flags); 191 netdev_dbg(ndp->ndev.dev, 192 "NCSI: host driver %srunning on channel %u\n", 193 ncm->data[3] & 0x1 ? "" : "not ", nc->id); 194 195 return 0; 196 } 197 198 static struct ncsi_aen_handler { 199 unsigned char type; 200 int payload; 201 int (*handler)(struct ncsi_dev_priv *ndp, 202 struct ncsi_aen_pkt_hdr *h); 203 } ncsi_aen_handlers[] = { 204 { NCSI_PKT_AEN_LSC, 12, ncsi_aen_handler_lsc }, 205 { NCSI_PKT_AEN_CR, 4, ncsi_aen_handler_cr }, 206 { NCSI_PKT_AEN_HNCDSC, 8, ncsi_aen_handler_hncdsc } 207 }; 208 209 int ncsi_aen_handler(struct ncsi_dev_priv *ndp, struct sk_buff *skb) 210 { 211 struct ncsi_aen_pkt_hdr *h; 212 struct ncsi_aen_handler *nah = NULL; 213 int i, ret; 214 215 /* Find the handler */ 216 h = (struct ncsi_aen_pkt_hdr *)skb_network_header(skb); 217 for (i = 0; i < ARRAY_SIZE(ncsi_aen_handlers); i++) { 218 if (ncsi_aen_handlers[i].type == h->type) { 219 nah = &ncsi_aen_handlers[i]; 220 break; 221 } 222 } 223 224 if (!nah) { 225 netdev_warn(ndp->ndev.dev, "Invalid AEN (0x%x) received\n", 226 h->type); 227 return -ENOENT; 228 } 229 230 ret = ncsi_validate_aen_pkt(h, nah->payload); 231 if (ret) { 232 netdev_warn(ndp->ndev.dev, 233 "NCSI: 'bad' packet ignored for AEN type 0x%x\n", 234 h->type); 235 goto out; 236 } 237 238 ret = nah->handler(ndp, h); 239 if (ret) 240 netdev_err(ndp->ndev.dev, 241 "NCSI: Handler for AEN type 0x%x returned %d\n", 242 h->type, ret); 243 out: 244 consume_skb(skb); 245 return ret; 246 } 247