1 files changed, 460 insertions, 215 deletions

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 4d59d50..5e7daa1 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -9,19 +9,16 @@
 #include <linux/skbuff.h>
 #include <linux/netdevice.h>
 #include <linux/genhd.h>
+#include <linux/moduleparam.h>
 #include <net/net_namespace.h>
 #include <asm/unaligned.h>
 #include "aoe.h"
 
-#define TIMERTICK (HZ / 10)
-#define MINTIMER (2 * TIMERTICK)
-#define MAXTIMER (HZ << 1)
-
 static int aoe_deadsecs = 60 * 3;
 module_param(aoe_deadsecs, int, 0644);
 MODULE_PARM_DESC(aoe_deadsecs, "After aoe_deadsecs seconds, give up and fail dev.");
 
-struct sk_buff *
+static struct sk_buff *
 new_skb(ulong len)
 {
 	struct sk_buff *skb;
@@ -43,12 +40,12 @@ new_skb(ulong len)
 }
 
 static struct frame *
-getframe(struct aoedev *d, int tag)
+getframe(struct aoetgt *t, int tag)
 {
 	struct frame *f, *e;
 
-	f = d->frames;
-	e = f + d->nframes;
+	f = t->frames;
+	e = f + t->nframes;
 	for (; f<e; f++)
 		if (f->tag == tag)
 			return f;
@@ -61,21 +58,21 @@ getframe(struct aoedev *d, int tag)
  * This driver reserves tag -1 to mean "unused frame."
  */
 static int
-newtag(struct aoedev *d)
+newtag(struct aoetgt *t)
 {
 	register ulong n;
 
 	n = jiffies & 0xffff;
-	return n |= (++d->lasttag & 0x7fff) << 16;
+	return n |= (++t->lasttag & 0x7fff) << 16;
 }
 
 static int
-aoehdr_atainit(struct aoedev *d, struct aoe_hdr *h)
+aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
 {
-	u32 host_tag = newtag(d);
+	u32 host_tag = newtag(t);
 
-	memcpy(h->src, d->ifp->dev_addr, sizeof h->src);
-	memcpy(h->dst, d->addr, sizeof h->dst);
+	memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
+	memcpy(h->dst, t->addr, sizeof h->dst);
 	h->type = __constant_cpu_to_be16(ETH_P_AOE);
 	h->verfl = AOE_HVER;
 	h->major = cpu_to_be16(d->aoemajor);
@@ -98,42 +95,103 @@ put_lba(struct aoe_atahdr *ah, sector_t lba)
 }
 
 static void
-aoecmd_ata_rw(struct aoedev *d, struct frame *f)
+ifrotate(struct aoetgt *t)
+{
+	t->ifp++;
+	if (t->ifp >= &t->ifs[NAOEIFS] || t->ifp->nd == NULL)
+		t->ifp = t->ifs;
+	if (t->ifp->nd == NULL) {
+		printk(KERN_INFO "aoe: no interface to rotate to\n");
+		BUG();
+	}
+}
+
+static struct frame *
+freeframe(struct aoedev *d)
 {
+	struct frame *f, *e;
+	struct aoetgt **t;
+	ulong n;
+
+	if (d->targets[0] == NULL) {	/* shouldn't happen, but I'm paranoid */
+		printk(KERN_ERR "aoe: NULL TARGETS!\n");
+		return NULL;
+	}
+	t = d->targets;
+	do {
+		if (t != d->htgt
+		&& (*t)->ifp->nd
+		&& (*t)->nout < (*t)->maxout) {
+			n = (*t)->nframes;
+			f = (*t)->frames;
+			e = f + n;
+			for (; f < e; f++) {
+				if (f->tag != FREETAG)
+					continue;
+				if (atomic_read(&skb_shinfo(f->skb)->dataref)
+					!= 1) {
+					n--;
+					continue;
+				}
+				skb_shinfo(f->skb)->nr_frags = 0;
+				f->skb->data_len = 0;
+				skb_trim(f->skb, 0);
+				d->tgt = t;
+				ifrotate(*t);
+				return f;
+			}
+			if (n == 0)	/* slow polling network card */
+				d->flags |= DEVFL_KICKME;
+		}
+		t++;
+	} while (t < &d->targets[NTARGETS] && *t);
+	return NULL;
+}
+
+static int
+aoecmd_ata_rw(struct aoedev *d)
+{
+	struct frame *f;
 	struct aoe_hdr *h;
 	struct aoe_atahdr *ah;
 	struct buf *buf;
+	struct bio_vec *bv;
+	struct aoetgt *t;
 	struct sk_buff *skb;
 	ulong bcnt;
-	register sector_t sector;
 	char writebit, extbit;
 
 	writebit = 0x10;
 	extbit = 0x4;
 
+	f = freeframe(d);
+	if (f == NULL)
+		return 0;
+	t = *d->tgt;
 	buf = d->inprocess;
-
-	sector = buf->sector;
-	bcnt = buf->bv_resid;
-	if (bcnt > d->maxbcnt)
-		bcnt = d->maxbcnt;
-
+	bv = buf->bv;
+	bcnt = t->ifp->maxbcnt;
+	if (bcnt == 0)
+		bcnt = DEFAULTBCNT;
+	if (bcnt > buf->bv_resid)
+		bcnt = buf->bv_resid;
 	/* initialize the headers & frame */
 	skb = f->skb;
 	h = (struct aoe_hdr *) skb_mac_header(skb);
 	ah = (struct aoe_atahdr *) (h+1);
 	skb_put(skb, sizeof *h + sizeof *ah);
 	memset(h, 0, skb->len);
-	f->tag = aoehdr_atainit(d, h);
+	f->tag = aoehdr_atainit(d, t, h);
+	t->nout++;
 	f->waited = 0;
 	f->buf = buf;
-	f->bufaddr = buf->bufaddr;
+	f->bufaddr = page_address(bv->bv_page) + buf->bv_off;
 	f->bcnt = bcnt;
-	f->lba = sector;
+	f->lba = buf->sector;
 
 	/* set up ata header */
 	ah->scnt = bcnt >> 9;
-	put_lba(ah, sector);
+	put_lba(ah, buf->sector);
 	if (d->flags & DEVFL_EXT) {
 		ah->aflags |= AOEAFL_EXT;
 	} else {
@@ -141,14 +199,14 @@ aoecmd_ata_rw(struct aoedev *d, struct frame *f)
 		ah->lba3 &= 0x0f;
 		ah->lba3 |= 0xe0;	/* LBA bit + obsolete 0xa0 */
 	}
-
 	if (bio_data_dir(buf->bio) == WRITE) {
-		skb_fill_page_desc(skb, 0, virt_to_page(f->bufaddr),
-			offset_in_page(f->bufaddr), bcnt);
+		skb_fill_page_desc(skb, 0, bv->bv_page, buf->bv_off, bcnt);
 		ah->aflags |= AOEAFL_WRITE;
 		skb->len += bcnt;
 		skb->data_len = bcnt;
+		t->wpkts++;
 	} else {
+		t->rpkts++;
 		writebit = 0;
 	}
 
@@ -156,29 +214,29 @@ aoecmd_ata_rw(struct aoedev *d, struct frame *f)
 
 	/* mark all tracking fields and load out */
 	buf->nframesout += 1;
-	buf->bufaddr += bcnt;
+	buf->bv_off += bcnt;
 	buf->bv_resid -= bcnt;
-/* printk(KERN_DEBUG "aoe: bv_resid=%ld\n", buf->bv_resid); */
 	buf->resid -= bcnt;
 	buf->sector += bcnt >> 9;
 	if (buf->resid == 0) {
 		d->inprocess = NULL;
 	} else if (buf->bv_resid == 0) {
-		buf->bv++;
-		WARN_ON(buf->bv->bv_len == 0);
-		buf->bv_resid = buf->bv->bv_len;
-		buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
+		buf->bv = ++bv;
+		buf->bv_resid = bv->bv_len;
+		WARN_ON(buf->bv_resid == 0);
+		buf->bv_off = bv->bv_offset;
 	}
 
-	skb->dev = d->ifp;
+	skb->dev = t->ifp->nd;
 	skb = skb_clone(skb, GFP_ATOMIC);
-	if (skb == NULL)
-		return;
-	if (d->sendq_hd)
-		d->sendq_tl->next = skb;
-	else
-		d->sendq_hd = skb;
-	d->sendq_tl = skb;
+	if (skb) {
+		if (d->sendq_hd)
+			d->sendq_tl->next = skb;
+		else
+			d->sendq_hd = skb;
+		d->sendq_tl = skb;
+	}
+	return 1;
 }
 
 /* some callers cannot sleep, and they can call this function,
@@ -232,62 +290,8 @@ cont:
 	return sl;
 }
 
-static struct frame *
-freeframe(struct aoedev *d)
-{
-	struct frame *f, *e;
-	int n = 0;
-
-	f = d->frames;
-	e = f + d->nframes;
-	for (; f<e; f++) {
-		if (f->tag != FREETAG)
-			continue;
-		if (atomic_read(&skb_shinfo(f->skb)->dataref) == 1) {
-			skb_shinfo(f->skb)->nr_frags = f->skb->data_len = 0;
-			skb_trim(f->skb, 0);
-			return f;
-		}
-		n++;
-	}
-	if (n == d->nframes)	/* wait for network layer */
-		d->flags |= DEVFL_KICKME;
-
-	return NULL;
-}
-
-/* enters with d->lock held */
-void
-aoecmd_work(struct aoedev *d)
-{
-	struct frame *f;
-	struct buf *buf;
-
-	if (d->flags & DEVFL_PAUSE) {
-		if (!aoedev_isbusy(d))
-			d->sendq_hd = aoecmd_cfg_pkts(d->aoemajor,
-						d->aoeminor, &d->sendq_tl);
-		return;
-	}
-
-loop:
-	f = freeframe(d);
-	if (f == NULL)
-		return;
-	if (d->inprocess == NULL) {
-		if (list_empty(&d->bufq))
-			return;
-		buf = container_of(d->bufq.next, struct buf, bufs);
-		list_del(d->bufq.next);
-/*printk(KERN_DEBUG "aoe: bi_size=%ld\n", buf->bio->bi_size); */
-		d->inprocess = buf;
-	}
-	aoecmd_ata_rw(d, f);
-	goto loop;
-}
-
 static void
-rexmit(struct aoedev *d, struct frame *f)
+resend(struct aoedev *d, struct aoetgt *t, struct frame *f)
 {
 	struct sk_buff *skb;
 	struct aoe_hdr *h;
@@ -295,41 +299,45 @@ rexmit(struct aoedev *d, struct frame *f)
 	char buf[128];
 	u32 n;
 
-	n = newtag(d);
+	ifrotate(t);
+	n = newtag(t);
+	skb = f->skb;
+	h = (struct aoe_hdr *) skb_mac_header(skb);
+	ah = (struct aoe_atahdr *) (h+1);
 
 	snprintf(buf, sizeof buf,
-		"%15s e%ld.%ld oldtag=%08x@%08lx newtag=%08x\n",
-		"retransmit",
-		d->aoemajor, d->aoeminor, f->tag, jiffies, n);
+		"%15s e%ld.%d oldtag=%08x@%08lx newtag=%08x "
+		"s=%012llx d=%012llx nout=%d\n",
+		"retransmit", d->aoemajor, d->aoeminor, f->tag, jiffies, n,
+		mac_addr(h->src), mac_addr(h->dst), t->nout);
 	aoechr_error(buf);
 
-	skb = f->skb;
-	h = (struct aoe_hdr *) skb_mac_header(skb);
-	ah = (struct aoe_atahdr *) (h+1);
 	f->tag = n;
 	h->tag = cpu_to_be32(n);
-	memcpy(h->dst, d->addr, sizeof h->dst);
-	memcpy(h->src, d->ifp->dev_addr, sizeof h->src);
-
-	n = DEFAULTBCNT / 512;
-	if (ah->scnt > n) {
-		ah->scnt = n;
+	memcpy(h->dst, t->addr, sizeof h->dst);
+	memcpy(h->src, t->ifp->nd->dev_addr, sizeof h->src);
+
+	switch (ah->cmdstat) {
+	default:
+		break;
+	case WIN_READ:
+	case WIN_READ_EXT:
+	case WIN_WRITE:
+	case WIN_WRITE_EXT:
+		put_lba(ah, f->lba);
+
+		n = f->bcnt;
+		if (n > DEFAULTBCNT)
+			n = DEFAULTBCNT;
+		ah->scnt = n >> 9;
 		if (ah->aflags & AOEAFL_WRITE) {
 			skb_fill_page_desc(skb, 0, virt_to_page(f->bufaddr),
-				offset_in_page(f->bufaddr), DEFAULTBCNT);
-			skb->len = sizeof *h + sizeof *ah + DEFAULTBCNT;
-			skb->data_len = DEFAULTBCNT;
-		}
-		if (++d->lostjumbo > (d->nframes << 1))
-		if (d->maxbcnt != DEFAULTBCNT) {
-			printk(KERN_INFO "aoe: e%ld.%ld: too many lost jumbo on %s - using 1KB frames.\n",
-				d->aoemajor, d->aoeminor, d->ifp->name);
-			d->maxbcnt = DEFAULTBCNT;
-			d->flags |= DEVFL_MAXBCNT;
+				offset_in_page(f->bufaddr), n);
+			skb->len = sizeof *h + sizeof *ah + n;
+			skb->data_len = n;
 		}
 	}
-
-	skb->dev = d->ifp;
+	skb->dev = t->ifp->nd;
 	skb = skb_clone(skb, GFP_ATOMIC);
 	if (skb == NULL)
 		return;
@@ -352,10 +360,92 @@ tsince(int tag)
 	return n;
 }
 
+static struct aoeif *
+getif(struct aoetgt *t, struct net_device *nd)
+{
+	struct aoeif *p, *e;
+
+	p = t->ifs;
+	e = p + NAOEIFS;
+	for (; p < e; p++)
+		if (p->nd == nd)
+			return p;
+	return NULL;
+}
+
+static struct aoeif *
+addif(struct aoetgt *t, struct net_device *nd)
+{
+	struct aoeif *p;
+
+	p = getif(t, NULL);
+	if (!p)
+		return NULL;
+	p->nd = nd;
+	p->maxbcnt = DEFAULTBCNT;
+	p->lost = 0;
+	p->lostjumbo = 0;
+	return p;
+}
+
+static void
+ejectif(struct aoetgt *t, struct aoeif *ifp)
+{
+	struct aoeif *e;
+	ulong n;
+
+	e = t->ifs + NAOEIFS - 1;
+	n = (e - ifp) * sizeof *ifp;
+	memmove(ifp, ifp+1, n);
+	e->nd = NULL;
+}
+
+static int
+sthtith(struct aoedev *d)
+{
+	struct frame *f, *e, *nf;
+	struct sk_buff *skb;
+	struct aoetgt *ht = *d->htgt;
+
+	f = ht->frames;
+	e = f + ht->nframes;
+	for (; f < e; f++) {
+		if (f->tag == FREETAG)
+			continue;
+		nf = freeframe(d);
+		if (!nf)
+			return 0;
+		skb = nf->skb;
+		*nf = *f;
+		f->skb = skb;
+		f->tag = FREETAG;
+		nf->waited = 0;
+		ht->nout--;
+		(*d->tgt)->nout++;
+		resend(d, *d->tgt, nf);
+	}
+	/* he's clean, he's useless.  take away his interfaces */
+	memset(ht->ifs, 0, sizeof ht->ifs);
+	d->htgt = NULL;
+	return 1;
+}
+
+static inline unsigned char
+ata_scnt(unsigned char *packet) {
+	struct aoe_hdr *h;
+	struct aoe_atahdr *ah;
+
+	h = (struct aoe_hdr *) packet;
+	ah = (struct aoe_atahdr *) (h+1);
+	return ah->scnt;
+}
+
 static void
 rexmit_timer(ulong vp)
 {
 	struct aoedev *d;
+	struct aoetgt *t, **tt, **te;
+	struct aoeif *ifp;
 	struct frame *f, *e;
 	struct sk_buff *sl;
 	register long timeout;
@@ -374,31 +464,79 @@ rexmit_timer(ulong vp)
 		spin_unlock_irqrestore(&d->lock, flags);
 		return;
 	}
-	f = d->frames;
-	e = f + d->nframes;
-	for (; f<e; f++) {
-		if (f->tag != FREETAG && tsince(f->tag) >= timeout) {
+	tt = d->targets;
+	te = tt + NTARGETS;
+	for (; tt < te && *tt; tt++) {
+		t = *tt;
+		f = t->frames;
+		e = f + t->nframes;
+		for (; f < e; f++) {
+			if (f->tag == FREETAG
+			|| tsince(f->tag) < timeout)
+				continue;
 			n = f->waited += timeout;
 			n /= HZ;
-			if (n > aoe_deadsecs) { /* waited too long for response */
+			if (n > aoe_deadsecs) {
+				/* waited too long.  device failure. */
 				aoedev_downdev(d);
 				break;
 			}
-			rexmit(d, f);
+
+			if (n > HELPWAIT /* see if another target can help */
+			&& (tt != d->targets || d->targets[1]))
+				d->htgt = tt;
+
+			if (t->nout == t->maxout) {
+				if (t->maxout > 1)
+					t->maxout--;
+				t->lastwadj = jiffies;
+			}
+
+			ifp = getif(t, f->skb->dev);
+			if (ifp && ++ifp->lost > (t->nframes << 1)
+			&& (ifp != t->ifs || t->ifs[1].nd)) {
+				ejectif(t, ifp);
+				ifp = NULL;
+			}
+
+			if (ata_scnt(skb_mac_header(f->skb)) > DEFAULTBCNT / 512
+			&& ifp && ++ifp->lostjumbo > (t->nframes << 1)
+			&& ifp->maxbcnt != DEFAULTBCNT) {
+				printk(KERN_INFO
+					"aoe: e%ld.%d: "
+					"too many lost jumbo on "
+					"%s:%012llx - "
+					"falling back to %d frames.\n",
+					d->aoemajor, d->aoeminor,
+					ifp->nd->name, mac_addr(t->addr),
+					DEFAULTBCNT);
+				ifp->maxbcnt = 0;
+			}
+			resend(d, t, f);
+		}
+
+		/* window check */
+		if (t->nout == t->maxout
+		&& t->maxout < t->nframes
+		&& (jiffies - t->lastwadj)/HZ > 10) {
+			t->maxout++;
+			t->lastwadj = jiffies;
 		}
 	}
-	if (d->flags & DEVFL_KICKME) {
+
+	if (d->sendq_hd) {
+		n = d->rttavg <<= 1;
+		if (n > MAXTIMER)
+			d->rttavg = MAXTIMER;
+	}
+
+	if (d->flags & DEVFL_KICKME || d->htgt) {
 		d->flags &= ~DEVFL_KICKME;
 		aoecmd_work(d);
 	}
 
 	sl = d->sendq_hd;
 	d->sendq_hd = d->sendq_tl = NULL;
-	if (sl) {
-		n = d->rttavg <<= 1;
-		if (n > MAXTIMER)
-			d->rttavg = MAXTIMER;
-	}
 
 	d->timer.expires = jiffies + TIMERTICK;
 	add_timer(&d->timer);
@@ -408,6 +546,25 @@ rexmit_timer(ulong vp)
 	aoenet_xmit(sl);
 }
 
+/* enters with d->lock held */
+void
+aoecmd_work(struct aoedev *d)
+{
+	struct buf *buf;
+loop:
+	if (d->htgt && !sthtith(d))
+		return;
+	if (d->inprocess == NULL) {
+		if (list_empty(&d->bufq))
+			return;
+		buf = container_of(d->bufq.next, struct buf, bufs);
+		list_del(d->bufq.next);
+		d->inprocess = buf;
+	}
+	if (aoecmd_ata_rw(d))
+		goto loop;
+}
+
 /* this function performs work that has been deferred until sleeping is OK
  */
 void
@@ -440,7 +597,7 @@ aoecmd_sleepwork(struct work_struct *work)
 }
 
 static void
-ataid_complete(struct aoedev *d, unsigned char *id)
+ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
 {
 	u64 ssize;
 	u16 n;
@@ -476,7 +633,7 @@ ataid_complete(struct aoedev *d, unsigned char *id)
 
 	if (d->ssize != ssize)
 		printk(KERN_INFO "aoe: %012llx e%lu.%lu v%04x has %llu sectors\n",
-			(unsigned long long)mac_addr(d->addr),
+			(unsigned long long)mac_addr(t->addr),
 			d->aoemajor, d->aoeminor,
 			d->fw_ver, (long long)ssize);
 	d->ssize = ssize;
@@ -484,15 +641,8 @@ ataid_complete(struct aoedev *d, unsigned char *id)
 	if (d->gd != NULL) {
 		d->gd->capacity = ssize;
 		d->flags |= DEVFL_NEWSIZE;
-	} else {
-		if (d->flags & DEVFL_GDALLOC) {
-			printk(KERN_ERR "aoe: can't schedule work for e%lu.%lu, %s\n",
-			       d->aoemajor, d->aoeminor,
-			       "it's already on!  This shouldn't happen.\n");
-			return;
-		}
+	} else
 		d->flags |= DEVFL_GDALLOC;
-	}
 	schedule_work(&d->work);
 }
 
@@ -519,6 +669,31 @@ calc_rttavg(struct aoedev *d, int rtt)
 	d->rttavg += n >> 2;
 }
 
+static struct aoetgt *
+gettgt(struct aoedev *d, char *addr)
+{
+	struct aoetgt **t, **e;
+
+	t = d->targets;
+	e = t + NTARGETS;
+	for (; t < e && *t; t++)
+		if (memcmp((*t)->addr, addr, sizeof((*t)->addr)) == 0)
+			return *t;
+	return NULL;
+}
+
+static inline void
+diskstats(struct gendisk *disk, struct bio *bio, ulong duration)
+{
+	unsigned long n_sect = bio->bi_size >> 9;
+	const int rw = bio_data_dir(bio);
+
+	disk_stat_inc(disk, ios[rw]);
+	disk_stat_add(disk, ticks[rw], duration);
+	disk_stat_add(disk, sectors[rw], n_sect);
+	disk_stat_add(disk, io_ticks, duration);
+}
+
 void
 aoecmd_ata_rsp(struct sk_buff *skb)
 {
@@ -528,6 +703,8 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 	struct frame *f;
 	struct buf *buf;
 	struct sk_buff *sl;
+	struct aoetgt *t;
+	struct aoeif *ifp;
 	register long n;
 	ulong flags;
 	char ebuf[128];
@@ -547,7 +724,15 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 	spin_lock_irqsave(&d->lock, flags);
 
 	n = be32_to_cpu(get_unaligned(&hin->tag));
-	f = getframe(d, n);
+	t = gettgt(d, hin->src);
+	if (t == NULL) {
+		printk(KERN_INFO "aoe: can't find target e%ld.%d:%012llx\n",
+			d->aoemajor, d->aoeminor,
+			(unsigned long long) mac_addr(hin->src));
+		spin_unlock_irqrestore(&d->lock, flags);
+		return;
+	}
+	f = getframe(t, n);
 	if (f == NULL) {
 		calc_rttavg(d, -tsince(n));
 		spin_unlock_irqrestore(&d->lock, flags);
@@ -569,8 +754,6 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 	ahout = (struct aoe_atahdr *) (hout+1);
 	buf = f->buf;
 
-	if (ahout->cmdstat == WIN_IDENTIFY)
-		d->flags &= ~DEVFL_PAUSE;
 	if (ahin->cmdstat & 0xa9) {	/* these bits cleared on success */
 		printk(KERN_ERR
 			"aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%ld\n",
@@ -579,14 +762,16 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 		if (buf)
 			buf->flags |= BUFFL_FAIL;
 	} else {
+		if (d->htgt && t == *d->htgt) /* I'll help myself, thank you. */
+			d->htgt = NULL;
 		n = ahout->scnt << 9;
 		switch (ahout->cmdstat) {
 		case WIN_READ:
 		case WIN_READ_EXT:
 			if (skb->len - sizeof *hin - sizeof *ahin < n) {
 				printk(KERN_ERR
-					"aoe: runt data size in read.  skb->len=%d\n",
-					skb->len);
+					"aoe: %s.  skb->len=%d need=%ld\n",
+					"runt data size in read", skb->len, n);
 				/* fail frame f?  just returning will rexmit. */
 				spin_unlock_irqrestore(&d->lock, flags);
 				return;
@@ -594,32 +779,18 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 			memcpy(f->bufaddr, ahin+1, n);
 		case WIN_WRITE:
 		case WIN_WRITE_EXT:
+			ifp = getif(t, skb->dev);
+			if (ifp) {
+				ifp->lost = 0;
+				if (n > DEFAULTBCNT)
+					ifp->lostjumbo = 0;
+			}
 			if (f->bcnt -= n) {
-				skb = f->skb;
+				f->lba += n >> 9;
 				f->bufaddr += n;
-				put_lba(ahout, f->lba += ahout->scnt);
-				n = f->bcnt;
-				if (n > DEFAULTBCNT)
-					n = DEFAULTBCNT;
-				ahout->scnt = n >> 9;
-				if (ahout->aflags & AOEAFL_WRITE) {
-					skb_fill_page_desc(skb, 0,
-						virt_to_page(f->bufaddr),
-						offset_in_page(f->bufaddr), n);
-					skb->len = sizeof *hout + sizeof *ahout + n;
-					skb->data_len = n;
-				}
-				f->tag = newtag(d);
-				hout->tag = cpu_to_be32(f->tag);
-				skb->dev = d->ifp;
-				skb = skb_clone(skb, GFP_ATOMIC);
-				spin_unlock_irqrestore(&d->lock, flags);
-				if (skb)
-					aoenet_xmit(skb);
-				return;
+				resend(d, t, f);
+				goto xmit;
 			}
-			if (n > DEFAULTBCNT)
-				d->lostjumbo = 0;
 			break;
 		case WIN_IDENTIFY:
 			if (skb->len - sizeof *hin - sizeof *ahin < 512) {
@@ -629,7 +800,7 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 				spin_unlock_irqrestore(&d->lock, flags);
 				return;
 			}
-			ataid_complete(d, (char *) (ahin+1));
+			ataid_complete(d, t, (char *) (ahin+1));
 			break;
 		default:
 			printk(KERN_INFO
@@ -640,28 +811,19 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 		}
 	}
 
-	if (buf) {
-		buf->nframesout -= 1;
-		if (buf->nframesout == 0 && buf->resid == 0) {
-			unsigned long duration = jiffies - buf->start_time;
-			unsigned long n_sect = buf->bio->bi_size >> 9;
-			struct gendisk *disk = d->gd;
-			const int rw = bio_data_dir(buf->bio);
-
-			disk_stat_inc(disk, ios[rw]);
-			disk_stat_add(disk, ticks[rw], duration);
-			disk_stat_add(disk, sectors[rw], n_sect);
-			disk_stat_add(disk, io_ticks, duration);
-			n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
-			bio_endio(buf->bio, n);
-			mempool_free(buf, d->bufpool);
-		}
+	if (buf && --buf->nframesout == 0 && buf->resid == 0) {
+		diskstats(d->gd, buf->bio, jiffies - buf->stime);
+		n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
+		bio_endio(buf->bio, n);
+		mempool_free(buf, d->bufpool);
 	}
 
 	f->buf = NULL;
 	f->tag = FREETAG;
+	t->nout--;
 
 	aoecmd_work(d);
+xmit:
 	sl = d->sendq_hd;
 	d->sendq_hd = d->sendq_tl = NULL;
 
@@ -679,23 +841,20 @@ aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
 	aoenet_xmit(sl);
 }
  
-/*
- * Since we only call this in one place (and it only prepares one frame)
- * we just return the skb.  Usually we'd chain it up to the aoedev sendq.
- */
-static struct sk_buff *
+struct sk_buff *
 aoecmd_ata_id(struct aoedev *d)
 {
 	struct aoe_hdr *h;
 	struct aoe_atahdr *ah;
 	struct frame *f;
 	struct sk_buff *skb;
+	struct aoetgt *t;
 
 	f = freeframe(d);
-	if (f == NULL) {
-		printk(KERN_ERR "aoe: can't get a frame. This shouldn't happen.\n");
+	if (f == NULL)
 		return NULL;
-	}
+
+	t = *d->tgt;
 
 	/* initialize the headers & frame */
 	skb = f->skb;
@@ -703,7 +862,8 @@ aoecmd_ata_id(struct aoedev *d)
 	ah = (struct aoe_atahdr *) (h+1);
 	skb_put(skb, sizeof *h + sizeof *ah);
 	memset(h, 0, skb->len);
-	f->tag = aoehdr_atainit(d, h);
+	f->tag = aoehdr_atainit(d, t, h);
+	t->nout++;
 	f->waited = 0;
 
 	/* set up ata header */
@@ -711,7 +871,7 @@ aoecmd_ata_id(struct aoedev *d)
 	ah->cmdstat = WIN_IDENTIFY;
 	ah->lba3 = 0xa0;
 
-	skb->dev = d->ifp;
+	skb->dev = t->ifp->nd;
 
 	d->rttavg = MAXTIMER;
 	d->timer.function = rexmit_timer;
@@ -719,12 +879,58 @@ aoecmd_ata_id(struct aoedev *d)
 	return skb_clone(skb, GFP_ATOMIC);
 }
  
+static struct aoetgt *
+addtgt(struct aoedev *d, char *addr, ulong nframes)
+{
+	struct aoetgt *t, **tt, **te;
+	struct frame *f, *e;
+
+	tt = d->targets;
+	te = tt + NTARGETS;
+	for (; tt < te && *tt; tt++)
+		;
+
+	if (tt == te)
+		return NULL;
+
+	t = kcalloc(1, sizeof *t, GFP_ATOMIC);
+	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
+	if (!t || !f)
+		goto bail;
+	t->nframes = nframes;
+	t->frames = f;
+	e = f + nframes;
+	for (; f < e; f++) {
+		f->tag = FREETAG;
+		f->skb = new_skb(ETH_ZLEN);
+		if (!f->skb)
+			break;
+	}
+	if (f != e) {
+		while (f > t->frames) {
+			f--;
+			dev_kfree_skb(f->skb);
+		}
+		goto bail;
+	}
+	memcpy(t->addr, addr, sizeof t->addr);
+	t->ifp = t->ifs;
+	t->maxout = t->nframes;
+	return *tt = t;
+bail:
+	kfree(t);
+	kfree(f);
+	return NULL;
+}
+
 void
 aoecmd_cfg_rsp(struct sk_buff *skb)
 {
 	struct aoedev *d;
 	struct aoe_hdr *h;
 	struct aoe_cfghdr *ch;
+	struct aoetgt *t;
+	struct aoeif *ifp;
 	ulong flags, sysminor, aoemajor;
 	struct sk_buff *sl;
 	enum { MAXFRAMES = 16 };
@@ -755,7 +961,7 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 	if (n > MAXFRAMES)	/* keep it reasonable */
 		n = MAXFRAMES;
 
-	d = aoedev_by_sysminor_m(sysminor, n);
+	d = aoedev_by_sysminor_m(sysminor);
 	if (d == NULL) {
 		printk(KERN_INFO "aoe: device sysminor_m failure\n");
 		return;
@@ -763,38 +969,77 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 
 	spin_lock_irqsave(&d->lock, flags);
 
-	/* permit device to migrate mac and network interface */
-	d->ifp = skb->dev;
-	memcpy(d->addr, h->src, sizeof d->addr);
-	if (!(d->flags & DEVFL_MAXBCNT)) {
-		n = d->ifp->mtu;
+	t = gettgt(d, h->src);
+	if (!t) {
+		t = addtgt(d, h->src, n);
+		if (!t) {
+			printk(KERN_INFO
+				"aoe: device addtgt failure; "
+				"too many targets?\n");
+			spin_unlock_irqrestore(&d->lock, flags);
+			return;
+		}
+	}
+	ifp = getif(t, skb->dev);
+	if (!ifp) {
+		ifp = addif(t, skb->dev);
+		if (!ifp) {
+			printk(KERN_INFO
+				"aoe: device addif failure; "
+				"too many interfaces?\n");
+			spin_unlock_irqrestore(&d->lock, flags);
+			return;
+		}
+	}
+	if (ifp->maxbcnt) {
+		n = ifp->nd->mtu;
 		n -= sizeof (struct aoe_hdr) + sizeof (struct aoe_atahdr);
 		n /= 512;
 		if (n > ch->scnt)
 			n = ch->scnt;
 		n = n ? n * 512 : DEFAULTBCNT;
-		if (n != d->maxbcnt) {
+		if (n != ifp->maxbcnt) {
 			printk(KERN_INFO
-				"aoe: e%ld.%ld: setting %d byte data frames on %s\n",
-				d->aoemajor, d->aoeminor, n, d->ifp->name);
-			d->maxbcnt = n;
+				"aoe: e%ld.%d: setting %d%s%s:%012llx\n",
+				d->aoemajor, d->aoeminor, n,
+				" byte data frames on ", ifp->nd->name,
+				(unsigned long long) mac_addr(t->addr));
+			ifp->maxbcnt = n;
 		}
 	}
 
 	/* don't change users' perspective */
-	if (d->nopen && !(d->flags & DEVFL_PAUSE)) {
+	if (d->nopen) {
 		spin_unlock_irqrestore(&d->lock, flags);
 		return;
 	}
-	d->flags |= DEVFL_PAUSE;	/* force pause */
-	d->mintimer = MINTIMER;
 	d->fw_ver = be16_to_cpu(ch->fwver);
 
-	/* check for already outstanding ataid */
-	sl = aoedev_isbusy(d) == 0 ? aoecmd_ata_id(d) : NULL;
+	sl = aoecmd_ata_id(d);
 
 	spin_unlock_irqrestore(&d->lock, flags);
 
 	aoenet_xmit(sl);
 }
 
+void
+aoecmd_cleanslate(struct aoedev *d)
+{
+	struct aoetgt **t, **te;
+	struct aoeif *p, *e;
+
+	d->mintimer = MINTIMER;
+
+	t = d->targets;
+	te = t + NTARGETS;
+	for (; t < te && *t; t++) {
+		(*t)->maxout = (*t)->nframes;
+		p = (*t)->ifs;
+		e = p + NAOEIFS;
+		for (; p < e; p++) {
+			p->lostjumbo = 0;
+			p->lost = 0;
+			p->maxbcnt = DEFAULTBCNT;
+		}
+	}
+}