release/src-rt-6.x.4708/linux/linux-2.6.36/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/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
  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
  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
  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
  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
 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
 161 aoenet_init(void)
 162 {
 163         dev_add_pack(&aoe_pt);
 164         return 0;
 165 }
 166
 167 void
 168 aoenet_exit(void)
 169 {
 170         dev_remove_pack(&aoe_pt);
 171 }