Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / block / aoe / aoenet.c
diff --git a/kernel/drivers/block/aoe/aoenet.c b/kernel/drivers/block/aoe/aoenet.c
new file mode 100644 (file)
index 0000000..63773a9
--- /dev/null
@@ -0,0 +1,223 @@
+/* Copyright (c) 2013 Coraid, Inc.  See COPYING for GPL terms. */
+/*
+ * aoenet.c
+ * Ethernet portion of AoE driver
+ */
+
+#include <linux/gfp.h>
+#include <linux/hdreg.h>
+#include <linux/blkdev.h>
+#include <linux/netdevice.h>
+#include <linux/moduleparam.h>
+#include <net/net_namespace.h>
+#include <asm/unaligned.h>
+#include "aoe.h"
+
+#define NECODES 5
+
+static char *aoe_errlist[] =
+{
+       "no such error",
+       "unrecognized command code",
+       "bad argument parameter",
+       "device unavailable",
+       "config string present",
+       "unsupported version"
+};
+
+enum {
+       IFLISTSZ = 1024,
+};
+
+static char aoe_iflist[IFLISTSZ];
+module_param_string(aoe_iflist, aoe_iflist, IFLISTSZ, 0600);
+MODULE_PARM_DESC(aoe_iflist, "aoe_iflist=dev1[,dev2...]");
+
+static wait_queue_head_t txwq;
+static struct ktstate kts;
+
+#ifndef MODULE
+static int __init aoe_iflist_setup(char *str)
+{
+       strncpy(aoe_iflist, str, IFLISTSZ);
+       aoe_iflist[IFLISTSZ - 1] = '\0';
+       return 1;
+}
+
+__setup("aoe_iflist=", aoe_iflist_setup);
+#endif
+
+static spinlock_t txlock;
+static struct sk_buff_head skbtxq;
+
+/* enters with txlock held */
+static int
+tx(int id) __must_hold(&txlock)
+{
+       struct sk_buff *skb;
+       struct net_device *ifp;
+
+       while ((skb = skb_dequeue(&skbtxq))) {
+               spin_unlock_irq(&txlock);
+               ifp = skb->dev;
+               if (dev_queue_xmit(skb) == NET_XMIT_DROP && net_ratelimit())
+                       pr_warn("aoe: packet could not be sent on %s.  %s\n",
+                               ifp ? ifp->name : "netif",
+                               "consider increasing tx_queue_len");
+               spin_lock_irq(&txlock);
+       }
+       return 0;
+}
+
+int
+is_aoe_netif(struct net_device *ifp)
+{
+       register char *p, *q;
+       register int len;
+
+       if (aoe_iflist[0] == '\0')
+               return 1;
+
+       p = aoe_iflist + strspn(aoe_iflist, WHITESPACE);
+       for (; *p; p = q + strspn(q, WHITESPACE)) {
+               q = p + strcspn(p, WHITESPACE);
+               if (q != p)
+                       len = q - p;
+               else
+                       len = strlen(p); /* last token in aoe_iflist */
+
+               if (strlen(ifp->name) == len && !strncmp(ifp->name, p, len))
+                       return 1;
+               if (q == p)
+                       break;
+       }
+
+       return 0;
+}
+
+int
+set_aoe_iflist(const char __user *user_str, size_t size)
+{
+       if (size >= IFLISTSZ)
+               return -EINVAL;
+
+       if (copy_from_user(aoe_iflist, user_str, size)) {
+               printk(KERN_INFO "aoe: copy from user failed\n");
+               return -EFAULT;
+       }
+       aoe_iflist[size] = 0x00;
+       return 0;
+}
+
+void
+aoenet_xmit(struct sk_buff_head *queue)
+{
+       struct sk_buff *skb, *tmp;
+       ulong flags;
+
+       skb_queue_walk_safe(queue, skb, tmp) {
+               __skb_unlink(skb, queue);
+               spin_lock_irqsave(&txlock, flags);
+               skb_queue_tail(&skbtxq, skb);
+               spin_unlock_irqrestore(&txlock, flags);
+               wake_up(&txwq);
+       }
+}
+
+/*
+ * (1) len doesn't include the header by default.  I want this.
+ */
+static int
+aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt, struct net_device *orig_dev)
+{
+       struct aoe_hdr *h;
+       struct aoe_atahdr *ah;
+       u32 n;
+       int sn;
+
+       if (dev_net(ifp) != &init_net)
+               goto exit;
+
+       skb = skb_share_check(skb, GFP_ATOMIC);
+       if (skb == NULL)
+               return 0;
+       if (!is_aoe_netif(ifp))
+               goto exit;
+       skb_push(skb, ETH_HLEN);        /* (1) */
+       sn = sizeof(*h) + sizeof(*ah);
+       if (skb->len >= sn) {
+               sn -= skb_headlen(skb);
+               if (sn > 0 && !__pskb_pull_tail(skb, sn))
+                       goto exit;
+       }
+       h = (struct aoe_hdr *) skb->data;
+       n = get_unaligned_be32(&h->tag);
+       if ((h->verfl & AOEFL_RSP) == 0 || (n & 1<<31))
+               goto exit;
+
+       if (h->verfl & AOEFL_ERR) {
+               n = h->err;
+               if (n > NECODES)
+                       n = 0;
+               if (net_ratelimit())
+                       printk(KERN_ERR
+                               "%s%d.%d@%s; ecode=%d '%s'\n",
+                               "aoe: error packet from ",
+                               get_unaligned_be16(&h->major),
+                               h->minor, skb->dev->name,
+                               h->err, aoe_errlist[n]);
+               goto exit;
+       }
+
+       switch (h->cmd) {
+       case AOECMD_ATA:
+               /* ata_rsp may keep skb for later processing or give it back */
+               skb = aoecmd_ata_rsp(skb);
+               break;
+       case AOECMD_CFG:
+               aoecmd_cfg_rsp(skb);
+               break;
+       default:
+               if (h->cmd >= AOECMD_VEND_MIN)
+                       break;  /* don't complain about vendor commands */
+               pr_info("aoe: unknown AoE command type 0x%02x\n", h->cmd);
+               break;
+       }
+
+       if (!skb)
+               return 0;
+exit:
+       dev_kfree_skb(skb);
+       return 0;
+}
+
+static struct packet_type aoe_pt __read_mostly = {
+       .type = __constant_htons(ETH_P_AOE),
+       .func = aoenet_rcv,
+};
+
+int __init
+aoenet_init(void)
+{
+       skb_queue_head_init(&skbtxq);
+       init_waitqueue_head(&txwq);
+       spin_lock_init(&txlock);
+       kts.lock = &txlock;
+       kts.fn = tx;
+       kts.waitq = &txwq;
+       kts.id = 0;
+       snprintf(kts.name, sizeof(kts.name), "aoe_tx%d", kts.id);
+       if (aoe_ktstart(&kts))
+               return -EAGAIN;
+       dev_add_pack(&aoe_pt);
+       return 0;
+}
+
+void
+aoenet_exit(void)
+{
+       aoe_ktstop(&kts);
+       skb_queue_purge(&skbtxq);
+       dev_remove_pack(&aoe_pt);
+}
+