1 /* Copyright (c) 2007 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 #ifndef MODULE
aoe_iflist_setup(char * str)37 static int __init aoe_iflist_setup(char *str)
38 {
39 	strncpy(aoe_iflist, str, IFLISTSZ);
40 	aoe_iflist[IFLISTSZ - 1] = '\0';
41 	return 1;
42 }
43 
44 __setup("aoe_iflist=", aoe_iflist_setup);
45 #endif
46 
47 int
is_aoe_netif(struct net_device * ifp)48 is_aoe_netif(struct net_device *ifp)
49 {
50 	register char *p, *q;
51 	register int len;
52 
53 	if (aoe_iflist[0] == '\0')
54 		return 1;
55 
56 	p = aoe_iflist + strspn(aoe_iflist, WHITESPACE);
57 	for (; *p; p = q + strspn(q, WHITESPACE)) {
58 		q = p + strcspn(p, WHITESPACE);
59 		if (q != p)
60 			len = q - p;
61 		else
62 			len = strlen(p); /* last token in aoe_iflist */
63 
64 		if (strlen(ifp->name) == len && !strncmp(ifp->name, p, len))
65 			return 1;
66 		if (q == p)
67 			break;
68 	}
69 
70 	return 0;
71 }
72 
73 int
set_aoe_iflist(const char __user * user_str,size_t size)74 set_aoe_iflist(const char __user *user_str, size_t size)
75 {
76 	if (size >= IFLISTSZ)
77 		return -EINVAL;
78 
79 	if (copy_from_user(aoe_iflist, user_str, size)) {
80 		printk(KERN_INFO "aoe: copy from user failed\n");
81 		return -EFAULT;
82 	}
83 	aoe_iflist[size] = 0x00;
84 	return 0;
85 }
86 
87 void
aoenet_xmit(struct sk_buff_head * queue)88 aoenet_xmit(struct sk_buff_head *queue)
89 {
90 	struct sk_buff *skb, *tmp;
91 
92 	skb_queue_walk_safe(queue, skb, tmp) {
93 		__skb_unlink(skb, queue);
94 		dev_queue_xmit(skb);
95 	}
96 }
97 
98 /*
99  * (1) len doesn't include the header by default.  I want this.
100  */
101 static int
aoenet_rcv(struct sk_buff * skb,struct net_device * ifp,struct packet_type * pt,struct net_device * orig_dev)102 aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt, struct net_device *orig_dev)
103 {
104 	struct aoe_hdr *h;
105 	u32 n;
106 
107 	if (dev_net(ifp) != &init_net)
108 		goto exit;
109 
110 	skb = skb_share_check(skb, GFP_ATOMIC);
111 	if (skb == NULL)
112 		return 0;
113 	if (skb_linearize(skb))
114 		goto exit;
115 	if (!is_aoe_netif(ifp))
116 		goto exit;
117 	skb_push(skb, ETH_HLEN);	/* (1) */
118 
119 	h = (struct aoe_hdr *) skb_mac_header(skb);
120 	n = get_unaligned_be32(&h->tag);
121 	if ((h->verfl & AOEFL_RSP) == 0 || (n & 1<<31))
122 		goto exit;
123 
124 	if (h->verfl & AOEFL_ERR) {
125 		n = h->err;
126 		if (n > NECODES)
127 			n = 0;
128 		if (net_ratelimit())
129 			printk(KERN_ERR
130 				"%s%d.%d@%s; ecode=%d '%s'\n",
131 				"aoe: error packet from ",
132 				get_unaligned_be16(&h->major),
133 				h->minor, skb->dev->name,
134 				h->err, aoe_errlist[n]);
135 		goto exit;
136 	}
137 
138 	switch (h->cmd) {
139 	case AOECMD_ATA:
140 		aoecmd_ata_rsp(skb);
141 		break;
142 	case AOECMD_CFG:
143 		aoecmd_cfg_rsp(skb);
144 		break;
145 	default:
146 		if (h->cmd >= AOECMD_VEND_MIN)
147 			break;	/* don't complain about vendor commands */
148 		printk(KERN_INFO "aoe: unknown cmd %d\n", h->cmd);
149 	}
150 exit:
151 	dev_kfree_skb(skb);
152 	return 0;
153 }
154 
155 static struct packet_type aoe_pt __read_mostly = {
156 	.type = __constant_htons(ETH_P_AOE),
157 	.func = aoenet_rcv,
158 };
159 
160 int __init
aoenet_init(void)161 aoenet_init(void)
162 {
163 	dev_add_pack(&aoe_pt);
164 	return 0;
165 }
166 
167 void
aoenet_exit(void)168 aoenet_exit(void)
169 {
170 	dev_remove_pack(&aoe_pt);
171 }
172 
173