1 /* Copyright (c) 2013 Coraid, Inc. See COPYING for GPL terms. */ 2 /* 3 * aoenet.c 4 * Ethernet portion of AoE driver 5 */ 6 7 #include <linux/gfp.h> 8 #include <linux/hdreg.h> 9 #include <linux/blkdev.h> 10 #include <linux/netdevice.h> 11 #include <linux/moduleparam.h> 12 #include <net/net_namespace.h> 13 #include <asm/unaligned.h> 14 #include "aoe.h" 15 16 #define NECODES 5 17 18 static char *aoe_errlist[] = 19 { 20 "no such error", 21 "unrecognized command code", 22 "bad argument parameter", 23 "device unavailable", 24 "config string present", 25 "unsupported version" 26 }; 27 28 enum { 29 IFLISTSZ = 1024, 30 }; 31 32 static char aoe_iflist[IFLISTSZ]; 33 module_param_string(aoe_iflist, aoe_iflist, IFLISTSZ, 0600); 34 MODULE_PARM_DESC(aoe_iflist, "aoe_iflist=dev1[,dev2...]"); 35 36 static wait_queue_head_t txwq; 37 static struct ktstate kts; 38 39 #ifndef MODULE 40 static int __init aoe_iflist_setup(char *str) 41 { 42 strscpy(aoe_iflist, str, IFLISTSZ); 43 return 1; 44 } 45 46 __setup("aoe_iflist=", aoe_iflist_setup); 47 #endif 48 49 static spinlock_t txlock; 50 static struct sk_buff_head skbtxq; 51 52 /* enters with txlock held */ 53 static int 54 tx(int id) __must_hold(&txlock) 55 { 56 struct sk_buff *skb; 57 struct net_device *ifp; 58 59 while ((skb = skb_dequeue(&skbtxq))) { 60 spin_unlock_irq(&txlock); 61 ifp = skb->dev; 62 if (dev_queue_xmit(skb) == NET_XMIT_DROP && net_ratelimit()) 63 pr_warn("aoe: packet could not be sent on %s. %s\n", 64 ifp ? ifp->name : "netif", 65 "consider increasing tx_queue_len"); 66 dev_put(ifp); 67 spin_lock_irq(&txlock); 68 } 69 return 0; 70 } 71 72 int 73 is_aoe_netif(struct net_device *ifp) 74 { 75 register char *p, *q; 76 register int len; 77 78 if (aoe_iflist[0] == '\0') 79 return 1; 80 81 p = aoe_iflist + strspn(aoe_iflist, WHITESPACE); 82 for (; *p; p = q + strspn(q, WHITESPACE)) { 83 q = p + strcspn(p, WHITESPACE); 84 if (q != p) 85 len = q - p; 86 else 87 len = strlen(p); /* last token in aoe_iflist */ 88 89 if (strlen(ifp->name) == len && !strncmp(ifp->name, p, len)) 90 return 1; 91 if (q == p) 92 break; 93 } 94 95 return 0; 96 } 97 98 int 99 set_aoe_iflist(const char __user *user_str, size_t size) 100 { 101 if (size >= IFLISTSZ) 102 return -EINVAL; 103 104 if (copy_from_user(aoe_iflist, user_str, size)) { 105 printk(KERN_INFO "aoe: copy from user failed\n"); 106 return -EFAULT; 107 } 108 aoe_iflist[size] = 0x00; 109 return 0; 110 } 111 112 void 113 aoenet_xmit(struct sk_buff_head *queue) 114 { 115 struct sk_buff *skb, *tmp; 116 ulong flags; 117 118 skb_queue_walk_safe(queue, skb, tmp) { 119 __skb_unlink(skb, queue); 120 spin_lock_irqsave(&txlock, flags); 121 skb_queue_tail(&skbtxq, skb); 122 spin_unlock_irqrestore(&txlock, flags); 123 wake_up(&txwq); 124 } 125 } 126 127 /* 128 * (1) len doesn't include the header by default. I want this. 129 */ 130 static int 131 aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt, struct net_device *orig_dev) 132 { 133 struct aoe_hdr *h; 134 struct aoe_atahdr *ah; 135 u32 n; 136 int sn; 137 138 if (dev_net(ifp) != &init_net) 139 goto exit; 140 141 skb = skb_share_check(skb, GFP_ATOMIC); 142 if (skb == NULL) 143 return 0; 144 if (!is_aoe_netif(ifp)) 145 goto exit; 146 skb_push(skb, ETH_HLEN); /* (1) */ 147 sn = sizeof(*h) + sizeof(*ah); 148 if (skb->len >= sn) { 149 sn -= skb_headlen(skb); 150 if (sn > 0 && !__pskb_pull_tail(skb, sn)) 151 goto exit; 152 } 153 h = (struct aoe_hdr *) skb->data; 154 n = get_unaligned_be32(&h->tag); 155 if ((h->verfl & AOEFL_RSP) == 0 || (n & 1<<31)) 156 goto exit; 157 158 if (h->verfl & AOEFL_ERR) { 159 n = h->err; 160 if (n > NECODES) 161 n = 0; 162 if (net_ratelimit()) 163 printk(KERN_ERR 164 "%s%d.%d@%s; ecode=%d '%s'\n", 165 "aoe: error packet from ", 166 get_unaligned_be16(&h->major), 167 h->minor, skb->dev->name, 168 h->err, aoe_errlist[n]); 169 goto exit; 170 } 171 172 switch (h->cmd) { 173 case AOECMD_ATA: 174 /* ata_rsp may keep skb for later processing or give it back */ 175 skb = aoecmd_ata_rsp(skb); 176 break; 177 case AOECMD_CFG: 178 aoecmd_cfg_rsp(skb); 179 break; 180 default: 181 if (h->cmd >= AOECMD_VEND_MIN) 182 break; /* don't complain about vendor commands */ 183 pr_info("aoe: unknown AoE command type 0x%02x\n", h->cmd); 184 break; 185 } 186 187 if (!skb) 188 return 0; 189 exit: 190 dev_kfree_skb(skb); 191 return 0; 192 } 193 194 static struct packet_type aoe_pt __read_mostly = { 195 .type = __constant_htons(ETH_P_AOE), 196 .func = aoenet_rcv, 197 }; 198 199 int __init 200 aoenet_init(void) 201 { 202 skb_queue_head_init(&skbtxq); 203 init_waitqueue_head(&txwq); 204 spin_lock_init(&txlock); 205 kts.lock = &txlock; 206 kts.fn = tx; 207 kts.waitq = &txwq; 208 kts.id = 0; 209 snprintf(kts.name, sizeof(kts.name), "aoe_tx%d", kts.id); 210 if (aoe_ktstart(&kts)) 211 return -EAGAIN; 212 dev_add_pack(&aoe_pt); 213 return 0; 214 } 215 216 void 217 aoenet_exit(void) 218 { 219 aoe_ktstop(&kts); 220 skb_queue_purge(&skbtxq); 221 dev_remove_pack(&aoe_pt); 222 } 223 224