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
18static 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
28enum {
29 IFLISTSZ = 1024,
30};
31
32static char aoe_iflist[IFLISTSZ];
33module_param_string(aoe_iflist, aoe_iflist, IFLISTSZ, 0600);
34MODULE_PARM_DESC(aoe_iflist, "aoe_iflist=dev1[,dev2...]");
35
36static wait_queue_head_t txwq;
37static struct ktstate kts;
38
39#ifndef MODULE
40static 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
49static spinlock_t txlock;
50static struct sk_buff_head skbtxq;
51
52/* enters with txlock held */
53static int
54tx(int id) __must_hold(&txlock)
55{
56 struct sk_buff *skb;
57 struct net_device *ifp;
58
59 while ((skb = skb_dequeue(list: &skbtxq))) {
60 spin_unlock_irq(lock: &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(dev: ifp);
67 spin_lock_irq(lock: &txlock);
68 }
69 return 0;
70}
71
72int
73is_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
98int
99set_aoe_iflist(const char __user *user_str, size_t size)
100{
101 if (size >= IFLISTSZ)
102 return -EINVAL;
103
104 if (copy_from_user(to: aoe_iflist, from: user_str, n: 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
112void
113aoenet_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, list: queue);
120 spin_lock_irqsave(&txlock, flags);
121 skb_queue_tail(list: &skbtxq, newsk: skb);
122 spin_unlock_irqrestore(lock: &txlock, flags);
123 wake_up(&txwq);
124 }
125}
126
127/*
128 * (1) len doesn't include the header by default. I want this.
129 */
130static int
131aoenet_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(dev: 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, delta: sn))
151 goto exit;
152 }
153 h = (struct aoe_hdr *) skb->data;
154 n = get_unaligned_be32(p: &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;
189exit:
190 dev_kfree_skb(skb);
191 return 0;
192}
193
194static struct packet_type aoe_pt __read_mostly = {
195 .type = __constant_htons(ETH_P_AOE),
196 .func = aoenet_rcv,
197};
198
199int __init
200aoenet_init(void)
201{
202 skb_queue_head_init(list: &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(buf: kts.name, size: sizeof(kts.name), fmt: "aoe_tx%d", kts.id);
210 if (aoe_ktstart(k: &kts))
211 return -EAGAIN;
212 dev_add_pack(pt: &aoe_pt);
213 return 0;
214}
215
216void
217aoenet_exit(void)
218{
219 aoe_ktstop(k: &kts);
220 skb_queue_purge(list: &skbtxq);
221 dev_remove_pack(pt: &aoe_pt);
222}
223
224

source code of linux/drivers/block/aoe/aoenet.c