drivers/block/aoe/aoenet.c

   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/hdreg.h>
   8 #include <linux/blkdev.h>
   9 #include <linux/netdevice.h>
  10 #include <linux/moduleparam.h>
  11 #include <net/net_namespace.h>
  12 #include <asm/unaligned.h>
  13 #include "aoe.h"
  14
  15 #define NECODES 5
  16
  17 static char *aoe_errlist[] =
  18 {
  19         "no such error",
  20         "unrecognized command code",
  21         "bad argument parameter",
  22         "device unavailable",
  23         "config string present",
  24         "unsupported version"
  25 };
  26
  27 enum {
  28         IFLISTSZ = 1024,
  29 };
  30
  31 static char aoe_iflist[IFLISTSZ];
  32 module_param_string(aoe_iflist, aoe_iflist, IFLISTSZ, 0600);
  33 MODULE_PARM_DESC(aoe_iflist, "aoe_iflist=\"dev1 [dev2 ...]\"");
  34
  35 #ifndef MODULE
  36 static int __init aoe_iflist_setup(char *str)
  37 {
  38         strncpy(aoe_iflist, str, IFLISTSZ);
  39         aoe_iflist[IFLISTSZ - 1] = '\0';
  40         return 1;
  41 }
  42
  43 __setup("aoe_iflist=", aoe_iflist_setup);
  44 #endif
  45
  46 int
  47 is_aoe_netif(struct net_device *ifp)
  48 {
  49         register char *p, *q;
  50         register int len;
  51
  52         if (aoe_iflist[0] == '\0')
  53                 return 1;
  54
  55         p = aoe_iflist + strspn(aoe_iflist, WHITESPACE);
  56         for (; *p; p = q + strspn(q, WHITESPACE)) {
  57                 q = p + strcspn(p, WHITESPACE);
  58                 if (q != p)
  59                         len = q - p;
  60                 else
  61                         len = strlen(p); /* last token in aoe_iflist */
  62
  63                 if (strlen(ifp->name) == len && !strncmp(ifp->name, p, len))
  64                         return 1;
  65                 if (q == p)
  66                         break;
  67         }
  68
  69         return 0;
  70 }
  71
  72 int
  73 set_aoe_iflist(const char __user *user_str, size_t size)
  74 {
  75         if (size >= IFLISTSZ)
  76                 return -EINVAL;
  77
  78         if (copy_from_user(aoe_iflist, user_str, size)) {
  79                 printk(KERN_INFO "aoe: copy from user failed\n");
  80                 return -EFAULT;
  81         }
  82         aoe_iflist[size] = 0x00;
  83         return 0;
  84 }
  85
  86 void
  87 aoenet_xmit(struct sk_buff_head *queue)
  88 {
  89         struct sk_buff *skb, *tmp;
  90
  91         skb_queue_walk_safe(queue, skb, tmp) {
  92                 __skb_unlink(skb, queue);
  93                 dev_queue_xmit(skb);
  94         }
  95 }
  96
  97 /*
  98  * (1) len doesn't include the header by default.  I want this.
  99  */
 100 static int
 101 aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt, struct net_device *orig_dev)
 102 {
 103         struct aoe_hdr *h;
 104         u32 n;
 105
 106         if (dev_net(ifp) != &init_net)
 107                 goto exit;
 108
 109         skb = skb_share_check(skb, GFP_ATOMIC);
 110         if (skb == NULL)
 111                 return 0;
 112         if (skb_linearize(skb))
 113                 goto exit;
 114         if (!is_aoe_netif(ifp))
 115                 goto exit;
 116         skb_push(skb, ETH_HLEN);        /* (1) */
 117
 118         h = (struct aoe_hdr *) skb_mac_header(skb);
 119         n = get_unaligned_be32(&h->tag);
 120         if ((h->verfl & AOEFL_RSP) == 0 || (n & 1<<31))
 121                 goto exit;
 122
 123         if (h->verfl & AOEFL_ERR) {
 124                 n = h->err;
 125                 if (n > NECODES)
 126                         n = 0;
 127                 if (net_ratelimit())
 128                         printk(KERN_ERR
 129                                 "%s%d.%d@%s; ecode=%d '%s'\n",
 130                                 "aoe: error packet from ",
 131                                 get_unaligned_be16(&h->major),
 132                                 h->minor, skb->dev->name,
 133                                 h->err, aoe_errlist[n]);
 134                 goto exit;
 135         }
 136
 137         switch (h->cmd) {
 138         case AOECMD_ATA:
 139                 aoecmd_ata_rsp(skb);
 140                 break;
 141         case AOECMD_CFG:
 142                 aoecmd_cfg_rsp(skb);
 143                 break;
 144         default:
 145                 if (h->cmd >= AOECMD_VEND_MIN)
 146                         break;  /* don't complain about vendor commands */
 147                 printk(KERN_INFO "aoe: unknown cmd %d\n", h->cmd);
 148         }
 149 exit:
 150         dev_kfree_skb(skb);
 151         return 0;
 152 }
 153
 154 static struct packet_type aoe_pt = {
 155         .type = __constant_htons(ETH_P_AOE),
 156         .func = aoenet_rcv,
 157 };
 158
 159 int __init
 160 aoenet_init(void)
 161 {
 162         dev_add_pack(&aoe_pt);
 163         return 0;
 164 }
 165
 166 void
 167 aoenet_exit(void)
 168 {
 169         dev_remove_pack(&aoe_pt);
 170 }
 171