1 /* Copyright (c) 2012 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 strncpy(aoe_iflist, str, IFLISTSZ); 43 aoe_iflist[IFLISTSZ - 1] = '\0'; 44 return 1; 45 } 46 47 __setup("aoe_iflist=", aoe_iflist_setup); 48 #endif 49 50 static spinlock_t txlock; 51 static struct sk_buff_head skbtxq; 52 53 /* enters with txlock held */ 54 static int 55 tx(void) 56 { 57 struct sk_buff *skb; 58 59 while ((skb = skb_dequeue(&skbtxq))) { 60 spin_unlock_irq(&txlock); 61 dev_queue_xmit(skb); 62 spin_lock_irq(&txlock); 63 } 64 return 0; 65 } 66 67 int 68 is_aoe_netif(struct net_device *ifp) 69 { 70 register char *p, *q; 71 register int len; 72 73 if (aoe_iflist[0] == '\0') 74 return 1; 75 76 p = aoe_iflist + strspn(aoe_iflist, WHITESPACE); 77 for (; *p; p = q + strspn(q, WHITESPACE)) { 78 q = p + strcspn(p, WHITESPACE); 79 if (q != p) 80 len = q - p; 81 else 82 len = strlen(p); /* last token in aoe_iflist */ 83 84 if (strlen(ifp->name) == len && !strncmp(ifp->name, p, len)) 85 return 1; 86 if (q == p) 87 break; 88 } 89 90 return 0; 91 } 92 93 int 94 set_aoe_iflist(const char __user *user_str, size_t size) 95 { 96 if (size >= IFLISTSZ) 97 return -EINVAL; 98 99 if (copy_from_user(aoe_iflist, user_str, size)) { 100 printk(KERN_INFO "aoe: copy from user failed\n"); 101 return -EFAULT; 102 } 103 aoe_iflist[size] = 0x00; 104 return 0; 105 } 106 107 void 108 aoenet_xmit(struct sk_buff_head *queue) 109 { 110 struct sk_buff *skb, *tmp; 111 ulong flags; 112 113 skb_queue_walk_safe(queue, skb, tmp) { 114 __skb_unlink(skb, queue); 115 spin_lock_irqsave(&txlock, flags); 116 skb_queue_tail(&skbtxq, skb); 117 spin_unlock_irqrestore(&txlock, flags); 118 wake_up(&txwq); 119 } 120 } 121 122 /* 123 * (1) len doesn't include the header by default. I want this. 124 */ 125 static int 126 aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt, struct net_device *orig_dev) 127 { 128 struct aoe_hdr *h; 129 struct aoe_atahdr *ah; 130 u32 n; 131 int sn; 132 133 if (dev_net(ifp) != &init_net) 134 goto exit; 135 136 skb = skb_share_check(skb, GFP_ATOMIC); 137 if (skb == NULL) 138 return 0; 139 if (!is_aoe_netif(ifp)) 140 goto exit; 141 skb_push(skb, ETH_HLEN); /* (1) */ 142 sn = sizeof(*h) + sizeof(*ah); 143 if (skb->len >= sn) { 144 sn -= skb_headlen(skb); 145 if (sn > 0 && !__pskb_pull_tail(skb, sn)) 146 goto exit; 147 } 148 h = (struct aoe_hdr *) skb->data; 149 n = get_unaligned_be32(&h->tag); 150 if ((h->verfl & AOEFL_RSP) == 0 || (n & 1<<31)) 151 goto exit; 152 153 if (h->verfl & AOEFL_ERR) { 154 n = h->err; 155 if (n > NECODES) 156 n = 0; 157 if (net_ratelimit()) 158 printk(KERN_ERR 159 "%s%d.%d@%s; ecode=%d '%s'\n", 160 "aoe: error packet from ", 161 get_unaligned_be16(&h->major), 162 h->minor, skb->dev->name, 163 h->err, aoe_errlist[n]); 164 goto exit; 165 } 166 167 switch (h->cmd) { 168 case AOECMD_ATA: 169 /* ata_rsp may keep skb for later processing or give it back */ 170 skb = aoecmd_ata_rsp(skb); 171 break; 172 case AOECMD_CFG: 173 aoecmd_cfg_rsp(skb); 174 break; 175 default: 176 if (h->cmd >= AOECMD_VEND_MIN) 177 break; /* don't complain about vendor commands */ 178 pr_info("aoe: unknown AoE command type 0x%02x\n", h->cmd); 179 break; 180 } 181 182 if (!skb) 183 return 0; 184 exit: 185 dev_kfree_skb(skb); 186 return 0; 187 } 188 189 static struct packet_type aoe_pt __read_mostly = { 190 .type = __constant_htons(ETH_P_AOE), 191 .func = aoenet_rcv, 192 }; 193 194 int __init 195 aoenet_init(void) 196 { 197 skb_queue_head_init(&skbtxq); 198 init_waitqueue_head(&txwq); 199 spin_lock_init(&txlock); 200 kts.lock = &txlock; 201 kts.fn = tx; 202 kts.waitq = &txwq; 203 kts.name = "aoe_tx"; 204 if (aoe_ktstart(&kts)) 205 return -EAGAIN; 206 dev_add_pack(&aoe_pt); 207 return 0; 208 } 209 210 void 211 aoenet_exit(void) 212 { 213 aoe_ktstop(&kts); 214 skb_queue_purge(&skbtxq); 215 dev_remove_pack(&aoe_pt); 216 } 217 218