1 files changed, 1083 insertions, 0 deletions

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
new file mode 100644
index 00000000..de0435e6
--- /dev/null
+++ b/drivers/block/aoe/aoecmd.c
@@ -0,0 +1,1083 @@
+/* Copyright (c) 2007 Coraid, Inc.  See COPYING for GPL terms. */
+/*
+ * aoecmd.c
+ * Filesystem request handling methods
+ */
+
+#include <linux/ata.h>
+#include <linux/slab.h>
+#include <linux/hdreg.h>
+#include <linux/blkdev.h>
+#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"
+
+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.");
+
+static int aoe_maxout = 16;
+module_param(aoe_maxout, int, 0644);
+MODULE_PARM_DESC(aoe_maxout,
+	"Only aoe_maxout outstanding packets for every MAC on eX.Y.");
+
+static struct sk_buff *
+new_skb(ulong len)
+{
+	struct sk_buff *skb;
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (skb) {
+		skb_reset_mac_header(skb);
+		skb_reset_network_header(skb);
+		skb->protocol = __constant_htons(ETH_P_AOE);
+	}
+	return skb;
+}
+
+static struct frame *
+getframe(struct aoetgt *t, int tag)
+{
+	struct frame *f, *e;
+
+	f = t->frames;
+	e = f + t->nframes;
+	for (; f<e; f++)
+		if (f->tag == tag)
+			return f;
+	return NULL;
+}
+
+/*
+ * Leave the top bit clear so we have tagspace for userland.
+ * The bottom 16 bits are the xmit tick for rexmit/rttavg processing.
+ * This driver reserves tag -1 to mean "unused frame."
+ */
+static int
+newtag(struct aoetgt *t)
+{
+	register ulong n;
+
+	n = jiffies & 0xffff;
+	return n |= (++t->lasttag & 0x7fff) << 16;
+}
+
+static int
+aoehdr_atainit(struct aoedev *d, struct aoetgt *t, struct aoe_hdr *h)
+{
+	u32 host_tag = newtag(t);
+
+	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);
+	h->minor = d->aoeminor;
+	h->cmd = AOECMD_ATA;
+	h->tag = cpu_to_be32(host_tag);
+
+	return host_tag;
+}
+
+static inline void
+put_lba(struct aoe_atahdr *ah, sector_t lba)
+{
+	ah->lba0 = lba;
+	ah->lba1 = lba >>= 8;
+	ah->lba2 = lba >>= 8;
+	ah->lba3 = lba >>= 8;
+	ah->lba4 = lba >>= 8;
+	ah->lba5 = lba >>= 8;
+}
+
+static void
+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 void
+skb_pool_put(struct aoedev *d, struct sk_buff *skb)
+{
+	__skb_queue_tail(&d->skbpool, skb);
+}
+
+static struct sk_buff *
+skb_pool_get(struct aoedev *d)
+{
+	struct sk_buff *skb = skb_peek(&d->skbpool);
+
+	if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) {
+		__skb_unlink(skb, &d->skbpool);
+		return skb;
+	}
+	if (skb_queue_len(&d->skbpool) < NSKBPOOLMAX &&
+	    (skb = new_skb(ETH_ZLEN)))
+		return skb;
+
+	return NULL;
+}
+
+/* freeframe is where we do our load balancing so it's a little hairy. */
+static struct frame *
+freeframe(struct aoedev *d)
+{
+	struct frame *f, *e, *rf;
+	struct aoetgt **t;
+	struct sk_buff *skb;
+
+	if (d->targets[0] == NULL) {	/* shouldn't happen, but I'm paranoid */
+		printk(KERN_ERR "aoe: NULL TARGETS!\n");
+		return NULL;
+	}
+	t = d->tgt;
+	t++;
+	if (t >= &d->targets[NTARGETS] || !*t)
+		t = d->targets;
+	for (;;) {
+		if ((*t)->nout < (*t)->maxout
+		&& t != d->htgt
+		&& (*t)->ifp->nd) {
+			rf = NULL;
+			f = (*t)->frames;
+			e = f + (*t)->nframes;
+			for (; f < e; f++) {
+				if (f->tag != FREETAG)
+					continue;
+				skb = f->skb;
+				if (!skb
+				&& !(f->skb = skb = new_skb(ETH_ZLEN)))
+					continue;
+				if (atomic_read(&skb_shinfo(skb)->dataref)
+					!= 1) {
+					if (!rf)
+						rf = f;
+					continue;
+				}
+gotone:				skb_shinfo(skb)->nr_frags = skb->data_len = 0;
+				skb_trim(skb, 0);
+				d->tgt = t;
+				ifrotate(*t);
+				return f;
+			}
+			/* Work can be done, but the network layer is
+			   holding our precious packets.  Try to grab
+			   one from the pool. */
+			f = rf;
+			if (f == NULL) {	/* more paranoia */
+				printk(KERN_ERR
+					"aoe: freeframe: %s.\n",
+					"unexpected null rf");
+				d->flags |= DEVFL_KICKME;
+				return NULL;
+			}
+			skb = skb_pool_get(d);
+			if (skb) {
+				skb_pool_put(d, f->skb);
+				f->skb = skb;
+				goto gotone;
+			}
+			(*t)->dataref++;
+			if ((*t)->nout == 0)
+				d->flags |= DEVFL_KICKME;
+		}
+		if (t == d->tgt)	/* we've looped and found nada */
+			break;
+		t++;
+		if (t >= &d->targets[NTARGETS] || !*t)
+			t = d->targets;
+	}
+	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;
+	char writebit, extbit;
+
+	writebit = 0x10;
+	extbit = 0x4;
+
+	f = freeframe(d);
+	if (f == NULL)
+		return 0;
+	t = *d->tgt;
+	buf = d->inprocess;
+	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, t, h);
+	t->nout++;
+	f->waited = 0;
+	f->buf = buf;
+	f->bufaddr = page_address(bv->bv_page) + buf->bv_off;
+	f->bcnt = bcnt;
+	f->lba = buf->sector;
+
+	/* set up ata header */
+	ah->scnt = bcnt >> 9;
+	put_lba(ah, buf->sector);
+	if (d->flags & DEVFL_EXT) {
+		ah->aflags |= AOEAFL_EXT;
+	} else {
+		extbit = 0;
+		ah->lba3 &= 0x0f;
+		ah->lba3 |= 0xe0;	/* LBA bit + obsolete 0xa0 */
+	}
+	if (bio_data_dir(buf->bio) == WRITE) {
+		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;
+	}
+
+	ah->cmdstat = ATA_CMD_PIO_READ | writebit | extbit;
+
+	/* mark all tracking fields and load out */
+	buf->nframesout += 1;
+	buf->bv_off += bcnt;
+	buf->bv_resid -= bcnt;
+	buf->resid -= bcnt;
+	buf->sector += bcnt >> 9;
+	if (buf->resid == 0) {
+		d->inprocess = NULL;
+	} else if (buf->bv_resid == 0) {
+		buf->bv = ++bv;
+		buf->bv_resid = bv->bv_len;
+		WARN_ON(buf->bv_resid == 0);
+		buf->bv_off = bv->bv_offset;
+	}
+
+	skb->dev = t->ifp->nd;
+	skb = skb_clone(skb, GFP_ATOMIC);
+	if (skb)
+		__skb_queue_tail(&d->sendq, skb);
+	return 1;
+}
+
+/* some callers cannot sleep, and they can call this function,
+ * transmitting the packets later, when interrupts are on
+ */
+static void
+aoecmd_cfg_pkts(ushort aoemajor, unsigned char aoeminor, struct sk_buff_head *queue)
+{
+	struct aoe_hdr *h;
+	struct aoe_cfghdr *ch;
+	struct sk_buff *skb;
+	struct net_device *ifp;
+
+	rcu_read_lock();
+	for_each_netdev_rcu(&init_net, ifp) {
+		dev_hold(ifp);
+		if (!is_aoe_netif(ifp))
+			goto cont;
+
+		skb = new_skb(sizeof *h + sizeof *ch);
+		if (skb == NULL) {
+			printk(KERN_INFO "aoe: skb alloc failure\n");
+			goto cont;
+		}
+		skb_put(skb, sizeof *h + sizeof *ch);
+		skb->dev = ifp;
+		__skb_queue_tail(queue, skb);
+		h = (struct aoe_hdr *) skb_mac_header(skb);
+		memset(h, 0, sizeof *h + sizeof *ch);
+
+		memset(h->dst, 0xff, sizeof h->dst);
+		memcpy(h->src, ifp->dev_addr, sizeof h->src);
+		h->type = __constant_cpu_to_be16(ETH_P_AOE);
+		h->verfl = AOE_HVER;
+		h->major = cpu_to_be16(aoemajor);
+		h->minor = aoeminor;
+		h->cmd = AOECMD_CFG;
+
+cont:
+		dev_put(ifp);
+	}
+	rcu_read_unlock();
+}
+
+static void
+resend(struct aoedev *d, struct aoetgt *t, struct frame *f)
+{
+	struct sk_buff *skb;
+	struct aoe_hdr *h;
+	struct aoe_atahdr *ah;
+	char buf[128];
+	u32 n;
+
+	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.%d oldtag=%08x@%08lx newtag=%08x s=%pm d=%pm nout=%d\n",
+		"retransmit", d->aoemajor, d->aoeminor, f->tag, jiffies, n,
+		h->src, h->dst, t->nout);
+	aoechr_error(buf);
+
+	f->tag = n;
+	h->tag = cpu_to_be32(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 ATA_CMD_PIO_READ:
+	case ATA_CMD_PIO_READ_EXT:
+	case ATA_CMD_PIO_WRITE:
+	case ATA_CMD_PIO_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), n);
+			skb->len = sizeof *h + sizeof *ah + n;
+			skb->data_len = n;
+		}
+	}
+	skb->dev = t->ifp->nd;
+	skb = skb_clone(skb, GFP_ATOMIC);
+	if (skb == NULL)
+		return;
+	__skb_queue_tail(&d->sendq, skb);
+}
+
+static int
+tsince(int tag)
+{
+	int n;
+
+	n = jiffies & 0xffff;
+	n -= tag & 0xffff;
+	if (n < 0)
+		n += 1<<16;
+	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 sk_buff_head queue;
+	struct aoedev *d;
+	struct aoetgt *t, **tt, **te;
+	struct aoeif *ifp;
+	struct frame *f, *e;
+	register long timeout;
+	ulong flags, n;
+
+	d = (struct aoedev *) vp;
+
+	/* timeout is always ~150% of the moving average */
+	timeout = d->rttavg;
+	timeout += timeout >> 1;
+
+	spin_lock_irqsave(&d->lock, flags);
+
+	if (d->flags & DEVFL_TKILL) {
+		spin_unlock_irqrestore(&d->lock, flags);
+		return;
+	}
+	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.  device failure. */
+				aoedev_downdev(d);
+				break;
+			}
+
+			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:%pm - "
+					"falling back to %d frames.\n",
+					d->aoemajor, d->aoeminor,
+					ifp->nd->name, 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 (!skb_queue_empty(&d->sendq)) {
+		n = d->rttavg <<= 1;
+		if (n > MAXTIMER)
+			d->rttavg = MAXTIMER;
+	}
+
+	if (d->flags & DEVFL_KICKME || d->htgt) {
+		d->flags &= ~DEVFL_KICKME;
+		aoecmd_work(d);
+	}
+
+	__skb_queue_head_init(&queue);
+	skb_queue_splice_init(&d->sendq, &queue);
+
+	d->timer.expires = jiffies + TIMERTICK;
+	add_timer(&d->timer);
+
+	spin_unlock_irqrestore(&d->lock, flags);
+
+	aoenet_xmit(&queue);
+}
+
+/* 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
+aoecmd_sleepwork(struct work_struct *work)
+{
+	struct aoedev *d = container_of(work, struct aoedev, work);
+
+	if (d->flags & DEVFL_GDALLOC)
+		aoeblk_gdalloc(d);
+
+	if (d->flags & DEVFL_NEWSIZE) {
+		struct block_device *bd;
+		unsigned long flags;
+		u64 ssize;
+
+		ssize = get_capacity(d->gd);
+		bd = bdget_disk(d->gd, 0);
+
+		if (bd) {
+			mutex_lock(&bd->bd_inode->i_mutex);
+			i_size_write(bd->bd_inode, (loff_t)ssize<<9);
+			mutex_unlock(&bd->bd_inode->i_mutex);
+			bdput(bd);
+		}
+		spin_lock_irqsave(&d->lock, flags);
+		d->flags |= DEVFL_UP;
+		d->flags &= ~DEVFL_NEWSIZE;
+		spin_unlock_irqrestore(&d->lock, flags);
+	}
+}
+
+static void
+ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
+{
+	u64 ssize;
+	u16 n;
+
+	/* word 83: command set supported */
+	n = get_unaligned_le16(&id[83 << 1]);
+
+	/* word 86: command set/feature enabled */
+	n |= get_unaligned_le16(&id[86 << 1]);
+
+	if (n & (1<<10)) {	/* bit 10: LBA 48 */
+		d->flags |= DEVFL_EXT;
+
+		/* word 100: number lba48 sectors */
+		ssize = get_unaligned_le64(&id[100 << 1]);
+
+		/* set as in ide-disk.c:init_idedisk_capacity */
+		d->geo.cylinders = ssize;
+		d->geo.cylinders /= (255 * 63);
+		d->geo.heads = 255;
+		d->geo.sectors = 63;
+	} else {
+		d->flags &= ~DEVFL_EXT;
+
+		/* number lba28 sectors */
+		ssize = get_unaligned_le32(&id[60 << 1]);
+
+		/* NOTE: obsolete in ATA 6 */
+		d->geo.cylinders = get_unaligned_le16(&id[54 << 1]);
+		d->geo.heads = get_unaligned_le16(&id[55 << 1]);
+		d->geo.sectors = get_unaligned_le16(&id[56 << 1]);
+	}
+
+	if (d->ssize != ssize)
+		printk(KERN_INFO
+			"aoe: %pm e%ld.%d v%04x has %llu sectors\n",
+			t->addr,
+			d->aoemajor, d->aoeminor,
+			d->fw_ver, (long long)ssize);
+	d->ssize = ssize;
+	d->geo.start = 0;
+	if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
+		return;
+	if (d->gd != NULL) {
+		set_capacity(d->gd, ssize);
+		d->flags |= DEVFL_NEWSIZE;
+	} else
+		d->flags |= DEVFL_GDALLOC;
+	schedule_work(&d->work);
+}
+
+static void
+calc_rttavg(struct aoedev *d, int rtt)
+{
+	register long n;
+
+	n = rtt;
+	if (n < 0) {
+		n = -rtt;
+		if (n < MINTIMER)
+			n = MINTIMER;
+		else if (n > MAXTIMER)
+			n = MAXTIMER;
+		d->mintimer += (n - d->mintimer) >> 1;
+	} else if (n < d->mintimer)
+		n = d->mintimer;
+	else if (n > MAXTIMER)
+		n = MAXTIMER;
+
+	/* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
+	n -= d->rttavg;
+	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, sector_t sector)
+{
+	unsigned long n_sect = bio->bi_size >> 9;
+	const int rw = bio_data_dir(bio);
+	struct hd_struct *part;
+	int cpu;
+
+	cpu = part_stat_lock();
+	part = disk_map_sector_rcu(disk, sector);
+
+	part_stat_inc(cpu, part, ios[rw]);
+	part_stat_add(cpu, part, ticks[rw], duration);
+	part_stat_add(cpu, part, sectors[rw], n_sect);
+	part_stat_add(cpu, part, io_ticks, duration);
+
+	part_stat_unlock();
+}
+
+void
+aoecmd_ata_rsp(struct sk_buff *skb)
+{
+	struct sk_buff_head queue;
+	struct aoedev *d;
+	struct aoe_hdr *hin, *hout;
+	struct aoe_atahdr *ahin, *ahout;
+	struct frame *f;
+	struct buf *buf;
+	struct aoetgt *t;
+	struct aoeif *ifp;
+	register long n;
+	ulong flags;
+	char ebuf[128];
+	u16 aoemajor;
+
+	hin = (struct aoe_hdr *) skb_mac_header(skb);
+	aoemajor = get_unaligned_be16(&hin->major);
+	d = aoedev_by_aoeaddr(aoemajor, hin->minor);
+	if (d == NULL) {
+		snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
+			"for unknown device %d.%d\n",
+			 aoemajor, hin->minor);
+		aoechr_error(ebuf);
+		return;
+	}
+
+	spin_lock_irqsave(&d->lock, flags);
+
+	n = get_unaligned_be32(&hin->tag);
+	t = gettgt(d, hin->src);
+	if (t == NULL) {
+		printk(KERN_INFO "aoe: can't find target e%ld.%d:%pm\n",
+			d->aoemajor, d->aoeminor, 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);
+		snprintf(ebuf, sizeof ebuf,
+			"%15s e%d.%d    tag=%08x@%08lx\n",
+			"unexpected rsp",
+			get_unaligned_be16(&hin->major),
+			hin->minor,
+			get_unaligned_be32(&hin->tag),
+			jiffies);
+		aoechr_error(ebuf);
+		return;
+	}
+
+	calc_rttavg(d, tsince(f->tag));
+
+	ahin = (struct aoe_atahdr *) (hin+1);
+	hout = (struct aoe_hdr *) skb_mac_header(f->skb);
+	ahout = (struct aoe_atahdr *) (hout+1);
+	buf = f->buf;
+
+	if (ahin->cmdstat & 0xa9) {	/* these bits cleared on success */
+		printk(KERN_ERR
+			"aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
+			ahout->cmdstat, ahin->cmdstat,
+			d->aoemajor, d->aoeminor);
+		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 ATA_CMD_PIO_READ:
+		case ATA_CMD_PIO_READ_EXT:
+			if (skb->len - sizeof *hin - sizeof *ahin < n) {
+				printk(KERN_ERR
+					"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;
+			}
+			memcpy(f->bufaddr, ahin+1, n);
+		case ATA_CMD_PIO_WRITE:
+		case ATA_CMD_PIO_WRITE_EXT:
+			ifp = getif(t, skb->dev);
+			if (ifp) {
+				ifp->lost = 0;
+				if (n > DEFAULTBCNT)
+					ifp->lostjumbo = 0;
+			}
+			if (f->bcnt -= n) {
+				f->lba += n >> 9;
+				f->bufaddr += n;
+				resend(d, t, f);
+				goto xmit;
+			}
+			break;
+		case ATA_CMD_ID_ATA:
+			if (skb->len - sizeof *hin - sizeof *ahin < 512) {
+				printk(KERN_INFO
+					"aoe: runt data size in ataid.  skb->len=%d\n",
+					skb->len);
+				spin_unlock_irqrestore(&d->lock, flags);
+				return;
+			}
+			ataid_complete(d, t, (char *) (ahin+1));
+			break;
+		default:
+			printk(KERN_INFO
+				"aoe: unrecognized ata command %2.2Xh for %d.%d\n",
+				ahout->cmdstat,
+				get_unaligned_be16(&hin->major),
+				hin->minor);
+		}
+	}
+
+	if (buf && --buf->nframesout == 0 && buf->resid == 0) {
+		diskstats(d->gd, buf->bio, jiffies - buf->stime, buf->sector);
+		if (buf->flags & BUFFL_FAIL)
+			bio_endio(buf->bio, -EIO);
+		else {
+			bio_flush_dcache_pages(buf->bio);
+			bio_endio(buf->bio, 0);
+		}
+		mempool_free(buf, d->bufpool);
+	}
+
+	f->buf = NULL;
+	f->tag = FREETAG;
+	t->nout--;
+
+	aoecmd_work(d);
+xmit:
+	__skb_queue_head_init(&queue);
+	skb_queue_splice_init(&d->sendq, &queue);
+
+	spin_unlock_irqrestore(&d->lock, flags);
+	aoenet_xmit(&queue);
+}
+
+void
+aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
+{
+	struct sk_buff_head queue;
+
+	__skb_queue_head_init(&queue);
+	aoecmd_cfg_pkts(aoemajor, aoeminor, &queue);
+	aoenet_xmit(&queue);
+}
+ 
+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)
+		return NULL;
+
+	t = *d->tgt;
+
+	/* 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, t, h);
+	t->nout++;
+	f->waited = 0;
+
+	/* set up ata header */
+	ah->scnt = 1;
+	ah->cmdstat = ATA_CMD_ID_ATA;
+	ah->lba3 = 0xa0;
+
+	skb->dev = t->ifp->nd;
+
+	d->rttavg = MAXTIMER;
+	d->timer.function = rexmit_timer;
+
+	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) {
+		printk(KERN_INFO
+			"aoe: device addtgt failure; too many targets\n");
+		return NULL;
+	}
+	t = kcalloc(1, sizeof *t, GFP_ATOMIC);
+	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
+	if (!t || !f) {
+		kfree(f);
+		kfree(t);
+		printk(KERN_INFO "aoe: cannot allocate memory to add target\n");
+		return NULL;
+	}
+
+	t->nframes = nframes;
+	t->frames = f;
+	e = f + nframes;
+	for (; f < e; f++)
+		f->tag = FREETAG;
+	memcpy(t->addr, addr, sizeof t->addr);
+	t->ifp = t->ifs;
+	t->maxout = t->nframes;
+	return *tt = t;
+}
+
+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;
+	u16 n;
+
+	h = (struct aoe_hdr *) skb_mac_header(skb);
+	ch = (struct aoe_cfghdr *) (h+1);
+
+	/*
+	 * Enough people have their dip switches set backwards to
+	 * warrant a loud message for this special case.
+	 */
+	aoemajor = get_unaligned_be16(&h->major);
+	if (aoemajor == 0xfff) {
+		printk(KERN_ERR "aoe: Warning: shelf address is all ones.  "
+			"Check shelf dip switches.\n");
+		return;
+	}
+
+	sysminor = SYSMINOR(aoemajor, h->minor);
+	if (sysminor * AOE_PARTITIONS + AOE_PARTITIONS > MINORMASK) {
+		printk(KERN_INFO "aoe: e%ld.%d: minor number too large\n",
+			aoemajor, (int) h->minor);
+		return;
+	}
+
+	n = be16_to_cpu(ch->bufcnt);
+	if (n > aoe_maxout)	/* keep it reasonable */
+		n = aoe_maxout;
+
+	d = aoedev_by_sysminor_m(sysminor);
+	if (d == NULL) {
+		printk(KERN_INFO "aoe: device sysminor_m failure\n");
+		return;
+	}
+
+	spin_lock_irqsave(&d->lock, flags);
+
+	t = gettgt(d, h->src);
+	if (!t) {
+		t = addtgt(d, h->src, n);
+		if (!t) {
+			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 != ifp->maxbcnt) {
+			printk(KERN_INFO
+				"aoe: e%ld.%d: setting %d%s%s:%pm\n",
+				d->aoemajor, d->aoeminor, n,
+				" byte data frames on ", ifp->nd->name,
+				t->addr);
+			ifp->maxbcnt = n;
+		}
+	}
+
+	/* don't change users' perspective */
+	if (d->nopen) {
+		spin_unlock_irqrestore(&d->lock, flags);
+		return;
+	}
+	d->fw_ver = be16_to_cpu(ch->fwver);
+
+	sl = aoecmd_ata_id(d);
+
+	spin_unlock_irqrestore(&d->lock, flags);
+
+	if (sl) {
+		struct sk_buff_head queue;
+		__skb_queue_head_init(&queue);
+		__skb_queue_tail(&queue, sl);
+		aoenet_xmit(&queue);
+	}
+}
+
+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;
+		}
+	}
+}