1 files changed, 629 insertions, 0 deletions

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
new file mode 100644
index 0000000..fb6d942
--- /dev/null
+++ b/drivers/block/aoe/aoecmd.c
@@ -0,0 +1,629 @@
+/* Copyright (c) 2004 Coraid, Inc.  See COPYING for GPL terms. */
+/*
+ * aoecmd.c
+ * Filesystem request handling methods
+ */
+
+#include <linux/hdreg.h>
+#include <linux/blkdev.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include "aoe.h"
+
+#define TIMERTICK (HZ / 10)
+#define MINTIMER (2 * TIMERTICK)
+#define MAXTIMER (HZ << 1)
+#define MAXWAIT (60 * 3)	/* After MAXWAIT seconds, give up and fail dev */
+
+static struct sk_buff *
+new_skb(struct net_device *if_dev, ulong len)
+{
+	struct sk_buff *skb;
+
+	skb = alloc_skb(len, GFP_ATOMIC);
+	if (skb) {
+		skb->nh.raw = skb->mac.raw = skb->data;
+		skb->dev = if_dev;
+		skb->protocol = __constant_htons(ETH_P_AOE);
+		skb->priority = 0;
+		skb_put(skb, len);
+		skb->next = skb->prev = NULL;
+
+		/* tell the network layer not to perform IP checksums
+		 * or to get the NIC to do it
+		 */
+		skb->ip_summed = CHECKSUM_NONE;
+	}
+	return skb;
+}
+
+static struct sk_buff *
+skb_prepare(struct aoedev *d, struct frame *f)
+{
+	struct sk_buff *skb;
+	char *p;
+
+	skb = new_skb(d->ifp, f->ndata + f->writedatalen);
+	if (!skb) {
+		printk(KERN_INFO "aoe: skb_prepare: failure to allocate skb\n");
+		return NULL;
+	}
+
+	p = skb->mac.raw;
+	memcpy(p, f->data, f->ndata);
+
+	if (f->writedatalen) {
+		p += sizeof(struct aoe_hdr) + sizeof(struct aoe_atahdr);
+		memcpy(p, f->bufaddr, f->writedatalen);
+	}
+
+	return skb;
+}
+
+static struct frame *
+getframe(struct aoedev *d, int tag)
+{
+	struct frame *f, *e;
+
+	f = d->frames;
+	e = f + d->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 aoedev *d)
+{
+	register ulong n;
+
+	n = jiffies & 0xffff;
+	return n |= (++d->lasttag & 0x7fff) << 16;
+}
+
+static int
+aoehdr_atainit(struct aoedev *d, struct aoe_hdr *h)
+{
+	u16 type = __constant_cpu_to_be16(ETH_P_AOE);
+	u16 aoemajor = __cpu_to_be16(d->aoemajor);
+	u32 host_tag = newtag(d);
+	u32 tag = __cpu_to_be32(host_tag);
+
+	memcpy(h->src, d->ifp->dev_addr, sizeof h->src);
+	memcpy(h->dst, d->addr, sizeof h->dst);
+	memcpy(h->type, &type, sizeof type);
+	h->verfl = AOE_HVER;
+	memcpy(h->major, &aoemajor, sizeof aoemajor);
+	h->minor = d->aoeminor;
+	h->cmd = AOECMD_ATA;
+	memcpy(h->tag, &tag, sizeof tag);
+
+	return host_tag;
+}
+
+static void
+aoecmd_ata_rw(struct aoedev *d, struct frame *f)
+{
+	struct aoe_hdr *h;
+	struct aoe_atahdr *ah;
+	struct buf *buf;
+	struct sk_buff *skb;
+	ulong bcnt;
+	register sector_t sector;
+	char writebit, extbit;
+
+	writebit = 0x10;
+	extbit = 0x4;
+
+	buf = d->inprocess;
+
+	sector = buf->sector;
+	bcnt = buf->bv_resid;
+	if (bcnt > MAXATADATA)
+		bcnt = MAXATADATA;
+
+	/* initialize the headers & frame */
+	h = (struct aoe_hdr *) f->data;
+	ah = (struct aoe_atahdr *) (h+1);
+	f->ndata = sizeof *h + sizeof *ah;
+	memset(h, 0, f->ndata);
+	f->tag = aoehdr_atainit(d, h);
+	f->waited = 0;
+	f->buf = buf;
+	f->bufaddr = buf->bufaddr;
+
+	/* set up ata header */
+	ah->scnt = bcnt >> 9;
+	ah->lba0 = sector;
+	ah->lba1 = sector >>= 8;
+	ah->lba2 = sector >>= 8;
+	ah->lba3 = sector >>= 8;
+	if (d->flags & DEVFL_EXT) {
+		ah->aflags |= AOEAFL_EXT;
+		ah->lba4 = sector >>= 8;
+		ah->lba5 = sector >>= 8;
+	} else {
+		extbit = 0;
+		ah->lba3 &= 0x0f;
+		ah->lba3 |= 0xe0;	/* LBA bit + obsolete 0xa0 */
+	}
+
+	if (bio_data_dir(buf->bio) == WRITE) {
+		ah->aflags |= AOEAFL_WRITE;
+		f->writedatalen = bcnt;
+	} else {
+		writebit = 0;
+		f->writedatalen = 0;
+	}
+
+	ah->cmdstat = WIN_READ | writebit | extbit;
+
+	/* mark all tracking fields and load out */
+	buf->nframesout += 1;
+	buf->bufaddr += bcnt;
+	buf->bv_resid -= bcnt;
+/* printk(KERN_INFO "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++;
+		buf->bv_resid = buf->bv->bv_len;
+		buf->bufaddr = page_address(buf->bv->bv_page) + buf->bv->bv_offset;
+	}
+
+	skb = skb_prepare(d, f);
+	if (skb) {
+		skb->next = d->skblist;
+		d->skblist = skb;
+	}
+}
+
+/* enters with d->lock held */
+void
+aoecmd_work(struct aoedev *d)
+{
+	struct frame *f;
+	struct buf *buf;
+loop:
+	f = getframe(d, FREETAG);
+	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_INFO "aoecmd_work: 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)
+{
+	struct sk_buff *skb;
+	struct aoe_hdr *h;
+	char buf[128];
+	u32 n;
+	u32 net_tag;
+
+	n = newtag(d);
+
+	snprintf(buf, sizeof buf,
+		"%15s e%ld.%ld oldtag=%08x@%08lx newtag=%08x\n",
+		"retransmit",
+		d->aoemajor, d->aoeminor, f->tag, jiffies, n);
+	aoechr_error(buf);
+
+	h = (struct aoe_hdr *) f->data;
+	f->tag = n;
+	net_tag = __cpu_to_be32(n);
+	memcpy(h->tag, &net_tag, sizeof net_tag);
+
+	skb = skb_prepare(d, f);
+	if (skb) {
+		skb->next = d->skblist;
+		d->skblist = skb;
+	}
+}
+
+static int
+tsince(int tag)
+{
+	int n;
+
+	n = jiffies & 0xffff;
+	n -= tag & 0xffff;
+	if (n < 0)
+		n += 1<<16;
+	return n;
+}
+
+static void
+rexmit_timer(ulong vp)
+{
+	struct aoedev *d;
+	struct frame *f, *e;
+	struct sk_buff *sl;
+	register long timeout;
+	ulong flags, n;
+
+	d = (struct aoedev *) vp;
+	sl = NULL;
+
+	/* 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) {
+tdie:		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) {
+			n = f->waited += timeout;
+			n /= HZ;
+			if (n > MAXWAIT) { /* waited too long.  device failure. */
+				aoedev_downdev(d);
+				goto tdie;
+			}
+			rexmit(d, f);
+		}
+	}
+
+	sl = d->skblist;
+	d->skblist = NULL;
+	if (sl) {
+		n = d->rttavg <<= 1;
+		if (n > MAXTIMER)
+			d->rttavg = MAXTIMER;
+	}
+
+	d->timer.expires = jiffies + TIMERTICK;
+	add_timer(&d->timer);
+
+	spin_unlock_irqrestore(&d->lock, flags);
+
+	aoenet_xmit(sl);
+}
+
+static void
+ataid_complete(struct aoedev *d, unsigned char *id)
+{
+	u64 ssize;
+	u16 n;
+
+	/* word 83: command set supported */
+	n = __le16_to_cpu(*((u16 *) &id[83<<1]));
+
+	/* word 86: command set/feature enabled */
+	n |= __le16_to_cpu(*((u16 *) &id[86<<1]));
+
+	if (n & (1<<10)) {	/* bit 10: LBA 48 */
+		d->flags |= DEVFL_EXT;
+
+		/* word 100: number lba48 sectors */
+		ssize = __le64_to_cpu(*((u64 *) &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 = __le32_to_cpu(*((u32 *) &id[60<<1]));
+
+		/* NOTE: obsolete in ATA 6 */
+		d->geo.cylinders = __le16_to_cpu(*((u16 *) &id[54<<1]));
+		d->geo.heads = __le16_to_cpu(*((u16 *) &id[55<<1]));
+		d->geo.sectors = __le16_to_cpu(*((u16 *) &id[56<<1]));
+	}
+	d->ssize = ssize;
+	d->geo.start = 0;
+	if (d->gd != NULL) {
+		d->gd->capacity = ssize;
+		d->flags |= DEVFL_UP;
+		return;
+	}
+	if (d->flags & DEVFL_WORKON) {
+		printk(KERN_INFO "aoe: ataid_complete: can't schedule work, it's already on!  "
+			"(This really shouldn't happen).\n");
+		return;
+	}
+	INIT_WORK(&d->work, aoeblk_gdalloc, d);
+	schedule_work(&d->work);
+	d->flags |= DEVFL_WORKON;
+}
+
+static void
+calc_rttavg(struct aoedev *d, int rtt)
+{
+	register long n;
+
+	n = rtt;
+	if (n < MINTIMER)
+		n = MINTIMER;
+	else if (n > MAXTIMER)
+		n = MAXTIMER;
+
+	/* g == .25; cf. Congestion Avoidance and Control, Jacobson & Karels; 1988 */
+	n -= d->rttavg;
+	d->rttavg += n >> 2;
+}
+
+void
+aoecmd_ata_rsp(struct sk_buff *skb)
+{
+	struct aoedev *d;
+	struct aoe_hdr *hin;
+	struct aoe_atahdr *ahin, *ahout;
+	struct frame *f;
+	struct buf *buf;
+	struct sk_buff *sl;
+	register long n;
+	ulong flags;
+	char ebuf[128];
+	
+	hin = (struct aoe_hdr *) skb->mac.raw;
+	d = aoedev_bymac(hin->src);
+	if (d == NULL) {
+		snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
+			"for unknown device %d.%d\n",
+			 __be16_to_cpu(*((u16 *) hin->major)),
+			hin->minor);
+		aoechr_error(ebuf);
+		return;
+	}
+
+	spin_lock_irqsave(&d->lock, flags);
+
+	f = getframe(d, __be32_to_cpu(*((u32 *) hin->tag)));
+	if (f == NULL) {
+		spin_unlock_irqrestore(&d->lock, flags);
+		snprintf(ebuf, sizeof ebuf,
+			"%15s e%d.%d    tag=%08x@%08lx\n",
+			"unexpected rsp",
+			__be16_to_cpu(*((u16 *) hin->major)),
+			hin->minor,
+			__be32_to_cpu(*((u32 *) hin->tag)),
+			jiffies);
+		aoechr_error(ebuf);
+		return;
+	}
+
+	calc_rttavg(d, tsince(f->tag));
+
+	ahin = (struct aoe_atahdr *) (hin+1);
+	ahout = (struct aoe_atahdr *) (f->data + sizeof(struct aoe_hdr));
+	buf = f->buf;
+
+	if (ahin->cmdstat & 0xa9) {	/* these bits cleared on success */
+		printk(KERN_CRIT "aoe: aoecmd_ata_rsp: ata error cmd=%2.2Xh "
+			"stat=%2.2Xh from e%ld.%ld\n", 
+			ahout->cmdstat, ahin->cmdstat,
+			d->aoemajor, d->aoeminor);
+		if (buf)
+			buf->flags |= BUFFL_FAIL;
+	} else {
+		switch (ahout->cmdstat) {
+		case WIN_READ:
+		case WIN_READ_EXT:
+			n = ahout->scnt << 9;
+			if (skb->len - sizeof *hin - sizeof *ahin < n) {
+				printk(KERN_CRIT "aoe: aoecmd_ata_rsp: runt "
+					"ata data size in read.  skb->len=%d\n",
+					skb->len);
+				/* fail frame f?  just returning will rexmit. */
+				spin_unlock_irqrestore(&d->lock, flags);
+				return;
+			}
+			memcpy(f->bufaddr, ahin+1, n);
+		case WIN_WRITE:
+		case WIN_WRITE_EXT:
+			break;
+		case WIN_IDENTIFY:
+			if (skb->len - sizeof *hin - sizeof *ahin < 512) {
+				printk(KERN_INFO "aoe: aoecmd_ata_rsp: runt data size "
+					"in ataid.  skb->len=%d\n", skb->len);
+				spin_unlock_irqrestore(&d->lock, flags);
+				return;
+			}
+			ataid_complete(d, (char *) (ahin+1));
+			/* d->flags |= DEVFL_WC_UPDATE; */
+			break;
+		default:
+			printk(KERN_INFO "aoe: aoecmd_ata_rsp: unrecognized "
+			       "outbound ata command %2.2Xh for %d.%d\n", 
+			       ahout->cmdstat,
+			       __be16_to_cpu(*((u16 *) hin->major)),
+			       hin->minor);
+		}
+	}
+
+	if (buf) {
+		buf->nframesout -= 1;
+		if (buf->nframesout == 0 && buf->resid == 0) {
+			n = (buf->flags & BUFFL_FAIL) ? -EIO : 0;
+			bio_endio(buf->bio, buf->bio->bi_size, n);
+			mempool_free(buf, d->bufpool);
+		}
+	}
+
+	f->buf = NULL;
+	f->tag = FREETAG;
+
+	aoecmd_work(d);
+
+	sl = d->skblist;
+	d->skblist = NULL;
+
+	spin_unlock_irqrestore(&d->lock, flags);
+
+	aoenet_xmit(sl);
+}
+
+void
+aoecmd_cfg(ushort aoemajor, unsigned char aoeminor)
+{
+	struct aoe_hdr *h;
+	struct aoe_cfghdr *ch;
+	struct sk_buff *skb, *sl;
+	struct net_device *ifp;
+	u16 aoe_type = __constant_cpu_to_be16(ETH_P_AOE);
+	u16 net_aoemajor = __cpu_to_be16(aoemajor);
+
+	sl = NULL;
+
+	read_lock(&dev_base_lock);
+	for (ifp = dev_base; ifp; dev_put(ifp), ifp = ifp->next) {
+		dev_hold(ifp);
+		if (!is_aoe_netif(ifp))
+			continue;
+
+		skb = new_skb(ifp, sizeof *h + sizeof *ch);
+		if (skb == NULL) {
+			printk(KERN_INFO "aoe: aoecmd_cfg: skb alloc failure\n");
+			continue;
+		}
+		h = (struct aoe_hdr *) skb->mac.raw;
+		memset(h, 0, sizeof *h + sizeof *ch);
+
+		memset(h->dst, 0xff, sizeof h->dst);
+		memcpy(h->src, ifp->dev_addr, sizeof h->src);
+		memcpy(h->type, &aoe_type, sizeof aoe_type);
+		h->verfl = AOE_HVER;
+		memcpy(h->major, &net_aoemajor, sizeof net_aoemajor);
+		h->minor = aoeminor;
+		h->cmd = AOECMD_CFG;
+
+		skb->next = sl;
+		sl = skb;
+	}
+	read_unlock(&dev_base_lock);
+
+	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 d->skblist.
+ */
+static struct sk_buff *
+aoecmd_ata_id(struct aoedev *d)
+{
+	struct aoe_hdr *h;
+	struct aoe_atahdr *ah;
+	struct frame *f;
+	struct sk_buff *skb;
+
+	f = getframe(d, FREETAG);
+	if (f == NULL) {
+		printk(KERN_CRIT "aoe: aoecmd_ata_id: can't get a frame.  "
+			"This shouldn't happen.\n");
+		return NULL;
+	}
+
+	/* initialize the headers & frame */
+	h = (struct aoe_hdr *) f->data;
+	ah = (struct aoe_atahdr *) (h+1);
+	f->ndata = sizeof *h + sizeof *ah;
+	memset(h, 0, f->ndata);
+	f->tag = aoehdr_atainit(d, h);
+	f->waited = 0;
+	f->writedatalen = 0;
+
+	/* this message initializes the device, so we reset the rttavg */
+	d->rttavg = MAXTIMER;
+
+	/* set up ata header */
+	ah->scnt = 1;
+	ah->cmdstat = WIN_IDENTIFY;
+	ah->lba3 = 0xa0;
+
+	skb = skb_prepare(d, f);
+
+	/* we now want to start the rexmit tracking */
+	d->flags &= ~DEVFL_TKILL;
+	d->timer.data = (ulong) d;
+	d->timer.function = rexmit_timer;
+	d->timer.expires = jiffies + TIMERTICK;
+	add_timer(&d->timer);
+
+	return skb;
+}
+ 
+void
+aoecmd_cfg_rsp(struct sk_buff *skb)
+{
+	struct aoedev *d;
+	struct aoe_hdr *h;
+	struct aoe_cfghdr *ch;
+	ulong flags, bufcnt, sysminor, aoemajor;
+	struct sk_buff *sl;
+	enum { MAXFRAMES = 8, MAXSYSMINOR = 255 };
+
+	h = (struct aoe_hdr *) skb->mac.raw;
+	ch = (struct aoe_cfghdr *) (h+1);
+
+	/*
+	 * Enough people have their dip switches set backwards to
+	 * warrant a loud message for this special case.
+	 */
+	aoemajor = __be16_to_cpu(*((u16 *) h->major));
+	if (aoemajor == 0xfff) {
+		printk(KERN_CRIT "aoe: aoecmd_cfg_rsp: Warning: shelf "
+			"address is all ones.  Check shelf dip switches\n");
+		return;
+	}
+
+	sysminor = SYSMINOR(aoemajor, h->minor);
+	if (sysminor > MAXSYSMINOR) {
+		printk(KERN_INFO "aoe: aoecmd_cfg_rsp: sysminor %ld too "
+			"large\n", sysminor);
+		return;
+	}
+
+	bufcnt = __be16_to_cpu(*((u16 *) ch->bufcnt));
+	if (bufcnt > MAXFRAMES)	/* keep it reasonable */
+		bufcnt = MAXFRAMES;
+
+	d = aoedev_set(sysminor, h->src, skb->dev, bufcnt);
+	if (d == NULL) {
+		printk(KERN_INFO "aoe: aoecmd_cfg_rsp: device set failure\n");
+		return;
+	}
+
+	spin_lock_irqsave(&d->lock, flags);
+
+	if (d->flags & (DEVFL_UP | DEVFL_CLOSEWAIT)) {
+		spin_unlock_irqrestore(&d->lock, flags);
+		return;
+	}
+
+	d->fw_ver = __be16_to_cpu(*((u16 *) ch->fwver));
+
+	/* we get here only if the device is new */
+	sl = aoecmd_ata_id(d);
+
+	spin_unlock_irqrestore(&d->lock, flags);
+
+	aoenet_xmit(sl);
+}
+