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* [PATCH 01/13] bring driver version number to 47
@ 2007-12-07 17:47 Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 02/13] handle multiple network paths to AoE device Ed L. Cashin
                   ` (11 more replies)
  0 siblings, 12 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:47 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

These patches were made against kernel 2.6.23-rc4 kernel with the
aoe-properly-initialise-the-request_queues-backing_dev_info patch
(currently in mm) applied.  They were submitted earlier and have been
modified to incorporate feedback from the kernel development
community.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoe.h |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index 07f02f8..4d0543a 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -1,5 +1,5 @@
 /* Copyright (c) 2006 Coraid, Inc.  See COPYING for GPL terms. */
-#define VERSION "32"
+#define VERSION "47"
 #define AOE_MAJOR 152
 #define DEVICE_NAME "aoe"
 
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 02/13] handle multiple network paths to AoE device
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 03/13] mac_addr: avoid 64-bit arch compiler warnings Ed L. Cashin
                   ` (10 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

A remote AoE device is something can process ATA commands and is
identified by an AoE shelf number and an AoE slot number.  Such a
device might have more than one network interface, and it might be
reachable by more than one local network interface.  This patch tracks
the available network paths available to each AoE device, allowing
them to be used more efficiently.

Andrew Morton asked about the call to msleep_interruptible in the
revalidate function.  Yes, if a signal is pending, then
msleep_interruptible will not return 0.  That means we will not loop
but will call aoenet_xmit with a NULL skb, which is a noop.  If the
system is too low on memory or the aoe driver is too low on frames,
then the user can hit control-C to interrupt the attempt to do a
revalidate.  I have added a comment to the code summarizing that.

Andrew Morton asked whether the allocation performed inside addtgt
could use a more relaxed allocation like GFP_KERNEL, but addtgt is
called when the aoedev lock has been locked with spin_lock_irqsave.
It would be nice to allocate the memory under fewer restrictions, but
targets are only added when the device is being discovered, and if the
target can't be added right now, we can try again in a minute when
then next AoE config query broadcast goes out.

Andrew Morton pointed out that the "too many targets" message could be
printed for failing GFP_ATOMIC allocations.  The last patch in this
series makes the messages more specific.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoe.h    |   57 +++--
 drivers/block/aoe/aoeblk.c |   62 ++++-
 drivers/block/aoe/aoechr.c |   17 +-
 drivers/block/aoe/aoecmd.c |  675 ++++++++++++++++++++++++++++++--------------
 drivers/block/aoe/aoedev.c |  168 +++++------
 drivers/block/aoe/aoenet.c |    9 +-
 6 files changed, 653 insertions(+), 335 deletions(-)

diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index 4d0543a..87df18b 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -76,10 +76,8 @@ enum {
 	DEVFL_EXT = (1<<2),	/* device accepts lba48 commands */
 	DEVFL_CLOSEWAIT = (1<<3), /* device is waiting for all closes to revalidate */
 	DEVFL_GDALLOC = (1<<4),	/* need to alloc gendisk */
-	DEVFL_PAUSE = (1<<5),
+	DEVFL_KICKME = (1<<5),	/* slow polling network card catch */
 	DEVFL_NEWSIZE = (1<<6),	/* need to update dev size in block layer */
-	DEVFL_MAXBCNT = (1<<7), /* d->maxbcnt is not changeable */
-	DEVFL_KICKME = (1<<8),
 
 	BUFFL_FAIL = 1,
 };
@@ -88,17 +86,24 @@ enum {
 	DEFAULTBCNT = 2 * 512,	/* 2 sectors */
 	NPERSHELF = 16,		/* number of slots per shelf address */
 	FREETAG = -1,
-	MIN_BUFS = 8,
+	MIN_BUFS = 16,
+	NTARGETS = 8,
+	NAOEIFS = 8,
+
+	TIMERTICK = HZ / 10,
+	MINTIMER = HZ >> 2,
+	MAXTIMER = HZ << 1,
+	HELPWAIT = 20,
 };
 
 struct buf {
 	struct list_head bufs;
-	ulong start_time;	/* for disk stats */
+	ulong stime;	/* for disk stats */
 	ulong flags;
 	ulong nframesout;
-	char *bufaddr;
 	ulong resid;
 	ulong bv_resid;
+	ulong bv_off;
 	sector_t sector;
 	struct bio *bio;
 	struct bio_vec *bv;
@@ -114,19 +119,37 @@ struct frame {
 	struct sk_buff *skb;
 };
 
+struct aoeif {
+	struct net_device *nd;
+	unsigned char lost;
+	unsigned char lostjumbo;
+	ushort maxbcnt;
+};
+
+struct aoetgt {
+	unsigned char addr[6];
+	ushort nframes;
+	struct frame *frames;
+	struct aoeif ifs[NAOEIFS];
+	struct aoeif *ifp;	/* current aoeif in use */
+	ushort nout;
+	ushort maxout;
+	u16 lasttag;		/* last tag sent */
+	u16 useme;
+	ulong lastwadj;		/* last window adjustment */
+	int wpkts, rpkts;
+};
+
 struct aoedev {
 	struct aoedev *next;
-	unsigned char addr[6];	/* remote mac addr */
-	ushort flags;
 	ulong sysminor;
 	ulong aoemajor;
-	ulong aoeminor;
+	u16 aoeminor;
+	u16 flags;
 	u16 nopen;		/* (bd_openers isn't available without sleeping) */
-	u16 lasttag;		/* last tag sent */
 	u16 rttavg;		/* round trip average of requests/responses */
 	u16 mintimer;
 	u16 fw_ver;		/* version of blade's firmware */
-	u16 maxbcnt;
 	struct work_struct work;/* disk create work struct */
 	struct gendisk *gd;
 	struct request_queue blkq;
@@ -134,15 +157,14 @@ struct aoedev {
 	sector_t ssize;
 	struct timer_list timer;
 	spinlock_t lock;
-	struct net_device *ifp;	/* interface ed is attached to */
 	struct sk_buff *sendq_hd; /* packets needing to be sent, list head */
 	struct sk_buff *sendq_tl;
 	mempool_t *bufpool;	/* for deadlock-free Buf allocation */
 	struct list_head bufq;	/* queue of bios to work on */
 	struct buf *inprocess;	/* the one we're currently working on */
-	ushort lostjumbo;
-	ushort nframes;		/* number of frames below */
-	struct frame *frames;
+	struct aoetgt *targets[NTARGETS];
+	struct aoetgt **tgt;	/* target in use when working */
+	struct aoetgt **htgt;	/* target needing rexmit assistance */
 };
 
 
@@ -160,12 +182,13 @@ void aoecmd_cfg(ushort aoemajor, unsigned char aoeminor);
 void aoecmd_ata_rsp(struct sk_buff *);
 void aoecmd_cfg_rsp(struct sk_buff *);
 void aoecmd_sleepwork(struct work_struct *);
-struct sk_buff *new_skb(ulong);
+void aoecmd_cleanslate(struct aoedev *);
+struct sk_buff *aoecmd_ata_id(struct aoedev *);
 
 int aoedev_init(void);
 void aoedev_exit(void);
 struct aoedev *aoedev_by_aoeaddr(int maj, int min);
-struct aoedev *aoedev_by_sysminor_m(ulong sysminor, ulong bufcnt);
+struct aoedev *aoedev_by_sysminor_m(ulong sysminor);
 void aoedev_downdev(struct aoedev *d);
 int aoedev_isbusy(struct aoedev *d);
 
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index ad00b3d..e10a7f3 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -22,22 +22,54 @@ static ssize_t aoedisk_show_state(struct gendisk * disk, char *page)
 	return snprintf(page, PAGE_SIZE,
 			"%s%s\n",
 			(d->flags & DEVFL_UP) ? "up" : "down",
-			(d->flags & DEVFL_PAUSE) ? ",paused" :
+			(d->flags & DEVFL_KICKME) ? ",kickme" :
 			(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
 	/* I'd rather see nopen exported so we can ditch closewait */
 }
 static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
 {
 	struct aoedev *d = disk->private_data;
+	struct aoetgt *t = d->targets[0];
 
+	if (t == NULL)
+		return snprintf(page, PAGE_SIZE, "none\n");
 	return snprintf(page, PAGE_SIZE, "%012llx\n",
-			(unsigned long long)mac_addr(d->addr));
+			(unsigned long long)mac_addr(t->addr));
 }
 static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
 {
 	struct aoedev *d = disk->private_data;
+	struct net_device *nds[8], **nd, **nnd, **ne;
+	struct aoetgt **t, **te;
+	struct aoeif *ifp, *e;
+	char *p;
+
+	memset(nds, 0, sizeof nds);
+	nd = nds;
+	ne = nd + ARRAY_SIZE(nds);
+	t = d->targets;
+	te = t + NTARGETS;
+	for (; t < te && *t; t++) {
+		ifp = (*t)->ifs;
+		e = ifp + NAOEIFS;
+		for (; ifp < e && ifp->nd; ifp++) {
+			for (nnd = nds; nnd < nd; nnd++)
+				if (*nnd == ifp->nd)
+					break;
+			if (nnd == nd && nd != ne)
+				*nd++ = ifp->nd;
+		}
+	}
 
-	return snprintf(page, PAGE_SIZE, "%s\n", d->ifp->name);
+	ne = nd;
+	nd = nds;
+	if (*nd == NULL)
+		return snprintf(page, PAGE_SIZE, "none\n");
+	for (p = page; nd < ne; nd++)
+		p += snprintf(p, PAGE_SIZE - (p-page), "%s%s",
+			p == page ? "" : ",", (*nd)->name);
+	p += snprintf(p, PAGE_SIZE - (p-page), "\n");
+	return p-page;
 }
 /* firmware version */
 static ssize_t aoedisk_show_fwver(struct gendisk * disk, char *page)
@@ -135,7 +167,23 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio)
 
 	blk_queue_bounce(q, &bio);
 
+	if (bio == NULL) {
+		printk(KERN_ERR "aoe: bio is NULL\n");
+		BUG();
+		return 0;
+	}
 	d = bio->bi_bdev->bd_disk->private_data;
+	if (d == NULL) {
+		printk(KERN_ERR "aoe: bd_disk->private_data is NULL\n");
+		BUG();
+		bio_endio(bio, -ENXIO);
+		return 0;
+	} else if (bio->bi_io_vec == NULL) {
+		printk(KERN_ERR "aoe: bi_io_vec is NULL\n");
+		BUG();
+		bio_endio(bio, -ENXIO);
+		return 0;
+	}
 	buf = mempool_alloc(d->bufpool, GFP_NOIO);
 	if (buf == NULL) {
 		printk(KERN_INFO "aoe: buf allocation failure\n");
@@ -144,14 +192,14 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio)
 	}
 	memset(buf, 0, sizeof(*buf));
 	INIT_LIST_HEAD(&buf->bufs);
-	buf->start_time = jiffies;
+	buf->stime = jiffies;
 	buf->bio = bio;
 	buf->resid = bio->bi_size;
 	buf->sector = bio->bi_sector;
 	buf->bv = &bio->bi_io_vec[bio->bi_idx];
-	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;
+	WARN_ON(buf->bv_resid == 0);
+	buf->bv_off = buf->bv->bv_offset;
 
 	spin_lock_irqsave(&d->lock, flags);
 
@@ -230,7 +278,7 @@ aoeblk_gdalloc(void *vp)
 	gd->fops = &aoe_bdops;
 	gd->private_data = d;
 	gd->capacity = d->ssize;
-	snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%ld",
+	snprintf(gd->disk_name, sizeof gd->disk_name, "etherd/e%ld.%d",
 		d->aoemajor, d->aoeminor);
 
 	gd->queue = &d->blkq;
diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 39e563e..1a5c4b5 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -6,6 +6,7 @@
 
 #include <linux/hdreg.h>
 #include <linux/blkdev.h>
+#include <linux/delay.h>
 #include "aoe.h"
 
 enum {
@@ -68,6 +69,7 @@ revalidate(const char __user *str, size_t size)
 	int major, minor, n;
 	ulong flags;
 	struct aoedev *d;
+	struct sk_buff *skb;
 	char buf[16];
 
 	if (size >= sizeof buf)
@@ -85,13 +87,20 @@ revalidate(const char __user *str, size_t size)
 	d = aoedev_by_aoeaddr(major, minor);
 	if (!d)
 		return -EINVAL;
-
 	spin_lock_irqsave(&d->lock, flags);
-	d->flags &= ~DEVFL_MAXBCNT;
-	d->flags |= DEVFL_PAUSE;
+	aoecmd_cleanslate(d);
+loop:
+	skb = aoecmd_ata_id(d);
 	spin_unlock_irqrestore(&d->lock, flags);
+	/* try again if we are able to sleep a bit,
+	 * otherwise give up this revalidation
+	 */
+	if (!skb && !msleep_interruptible(200)) {
+		spin_lock_irqsave(&d->lock, flags);
+		goto loop;
+	}
+	aoenet_xmit(skb);
 	aoecmd_cfg(major, minor);
-
 	return 0;
 }
 
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;
+		}
+	}
+}
diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index 51f5071..a4d625a 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -15,15 +15,18 @@ static spinlock_t devlist_lock;
 int
 aoedev_isbusy(struct aoedev *d)
 {
+	struct aoetgt **t, **te;
 	struct frame *f, *e;
 
-	f = d->frames;
-	e = f + d->nframes;
-	do {
-		if (f->tag != FREETAG)
-			return 1;
-	} while (++f < e);
-
+	t = d->targets;
+	te = t + NTARGETS;
+	for (; t < te && *t; t++) {
+		f = (*t)->frames;
+		e = f + (*t)->nframes;
+		for (; f < e; f++)
+			if (f->tag != FREETAG)
+				return 1;
+	}
 	return 0;
 }
 
@@ -55,75 +58,41 @@ dummy_timer(ulong vp)
 	add_timer(&d->timer);
 }
 
-/* called with devlist lock held */
-static struct aoedev *
-aoedev_newdev(ulong nframes)
-{
-	struct aoedev *d;
-	struct frame *f, *e;
-
-	d = kzalloc(sizeof *d, GFP_ATOMIC);
-	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
- 	switch (!d || !f) {
- 	case 0:
- 		d->nframes = nframes;
- 		d->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)
- 			break;
- 		while (f > d->frames) {
- 			f--;
- 			dev_kfree_skb(f->skb);
- 		}
- 	default:
- 		if (f)
- 			kfree(f);
- 		if (d)
- 			kfree(d);
-		return NULL;
-	}
-	INIT_WORK(&d->work, aoecmd_sleepwork);
-	spin_lock_init(&d->lock);
-	init_timer(&d->timer);
-	d->timer.data = (ulong) d;
-	d->timer.function = dummy_timer;
-	d->timer.expires = jiffies + HZ;
-	add_timer(&d->timer);
-	d->bufpool = NULL;	/* defer to aoeblk_gdalloc */
-	INIT_LIST_HEAD(&d->bufq);
-	d->next = devlist;
-	devlist = d;
-
-	return d;
-}
-
 void
 aoedev_downdev(struct aoedev *d)
 {
+	struct aoetgt **t, **te;
 	struct frame *f, *e;
 	struct buf *buf;
 	struct bio *bio;
 
-	f = d->frames;
-	e = f + d->nframes;
-	for (; f<e; f->tag = FREETAG, f->buf = NULL, f++) {
-		if (f->tag == FREETAG || f->buf == NULL)
-			continue;
-		buf = f->buf;
-		bio = buf->bio;
-		if (--buf->nframesout == 0) {
-			mempool_free(buf, d->bufpool);
-			bio_endio(bio, -EIO);
+	t = d->targets;
+	te = t + NTARGETS;
+	for (; t < te && *t; t++) {
+		f = (*t)->frames;
+		e = f + (*t)->nframes;
+		for (; f < e; f->tag = FREETAG, f->buf = NULL, f++) {
+			if (f->tag == FREETAG || f->buf == NULL)
+				continue;
+			buf = f->buf;
+			bio = buf->bio;
+			if (--buf->nframesout == 0
+			&& buf != d->inprocess) {
+				mempool_free(buf, d->bufpool);
+				bio_endio(bio, -EIO);
+			}
 		}
-		skb_shinfo(f->skb)->nr_frags = f->skb->data_len = 0;
+		(*t)->maxout = (*t)->nframes;
+		(*t)->nout = 0;
+	}
+	buf = d->inprocess;
+	if (buf) {
+		bio = buf->bio;
+		mempool_free(buf, d->bufpool);
+		bio_endio(bio, -EIO);
 	}
 	d->inprocess = NULL;
+	d->htgt = NULL;
 
 	while (!list_empty(&d->bufq)) {
 		buf = container_of(d->bufq.next, struct buf, bufs);
@@ -136,12 +105,12 @@ aoedev_downdev(struct aoedev *d)
 	if (d->gd)
 		d->gd->capacity = 0;
 
-	d->flags &= ~(DEVFL_UP | DEVFL_PAUSE);
+	d->flags &= ~DEVFL_UP;
 }
 
 /* find it or malloc it */
 struct aoedev *
-aoedev_by_sysminor_m(ulong sysminor, ulong bufcnt)
+aoedev_by_sysminor_m(ulong sysminor)
 {
 	struct aoedev *d;
 	ulong flags;
@@ -151,40 +120,61 @@ aoedev_by_sysminor_m(ulong sysminor, ulong bufcnt)
 	for (d=devlist; d; d=d->next)
 		if (d->sysminor == sysminor)
 			break;
-
-	if (d == NULL) {
-		d = aoedev_newdev(bufcnt);
-	 	if (d == NULL) {
-			spin_unlock_irqrestore(&devlist_lock, flags);
-			printk(KERN_INFO "aoe: aoedev_newdev failure.\n");
-			return NULL;
-		}
-		d->sysminor = sysminor;
-		d->aoemajor = AOEMAJOR(sysminor);
-		d->aoeminor = AOEMINOR(sysminor);
-	}
-
+	if (d)
+		goto out;
+	d = kcalloc(1, sizeof *d, GFP_ATOMIC);
+	if (!d)
+		goto out;
+	INIT_WORK(&d->work, aoecmd_sleepwork);
+	spin_lock_init(&d->lock);
+	init_timer(&d->timer);
+	d->timer.data = (ulong) d;
+	d->timer.function = dummy_timer;
+	d->timer.expires = jiffies + HZ;
+	add_timer(&d->timer);
+	d->bufpool = NULL;	/* defer to aoeblk_gdalloc */
+	d->tgt = d->targets;
+	INIT_LIST_HEAD(&d->bufq);
+	d->sysminor = sysminor;
+	d->aoemajor = AOEMAJOR(sysminor);
+	d->aoeminor = AOEMINOR(sysminor);
+	d->mintimer = MINTIMER;
+	d->next = devlist;
+	devlist = d;
+ out:
 	spin_unlock_irqrestore(&devlist_lock, flags);
 	return d;
 }
 
 static void
-aoedev_freedev(struct aoedev *d)
+freetgt(struct aoetgt *t)
 {
 	struct frame *f, *e;
 
+	f = t->frames;
+	e = f + t->nframes;
+	for (; f < e; f++) {
+		skb_shinfo(f->skb)->nr_frags = 0;
+		dev_kfree_skb(f->skb);
+	}
+	kfree(t->frames);
+	kfree(t);
+}
+
+static void
+aoedev_freedev(struct aoedev *d)
+{
+	struct aoetgt **t, **e;
+
 	if (d->gd) {
 		aoedisk_rm_sysfs(d);
 		del_gendisk(d->gd);
 		put_disk(d->gd);
 	}
-	f = d->frames;
-	e = f + d->nframes;
-	for (; f<e; f++) {
-		skb_shinfo(f->skb)->nr_frags = 0;
-		dev_kfree_skb(f->skb);
-	}
-	kfree(d->frames);
+	t = d->targets;
+	e = t + NTARGETS;
+	for (; t < e && *t; t++)
+		freetgt(*t);
 	if (d->bufpool)
 		mempool_destroy(d->bufpool);
 	kfree(d);
diff --git a/drivers/block/aoe/aoenet.c b/drivers/block/aoe/aoenet.c
index 4e6deb7..7a38a45 100644
--- a/drivers/block/aoe/aoenet.c
+++ b/drivers/block/aoe/aoenet.c
@@ -137,9 +137,12 @@ aoenet_rcv(struct sk_buff *skb, struct net_device *ifp, struct packet_type *pt,
 		if (n > NECODES)
 			n = 0;
 		if (net_ratelimit())
-			printk(KERN_ERR "aoe: error packet from %d.%d; ecode=%d '%s'\n",
-			       be16_to_cpu(get_unaligned(&h->major)), h->minor,
-			       h->err, aoe_errlist[n]);
+			printk(KERN_ERR
+				"%s%d.%d@%s; ecode=%d '%s'\n",
+				"aoe: error packet from ",
+				be16_to_cpu(get_unaligned(&h->major)),
+				h->minor, skb->dev->name,
+				h->err, aoe_errlist[n]);
 		goto exit;
 	}
 
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 03/13] mac_addr: avoid 64-bit arch compiler warnings
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 02/13] handle multiple network paths to AoE device Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 04/13] clean up udev configuration example Ed L. Cashin
                   ` (9 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

By returning unsigned long long, mac_addr does not generate compiler
warnings on 64-bit architectures.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoe.h    |    2 +-
 drivers/block/aoe/aoeblk.c |    3 +--
 drivers/block/aoe/aoecmd.c |   10 +++++-----
 drivers/block/aoe/aoenet.c |    4 ++--
 4 files changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index 87df18b..aecaac3 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -198,4 +198,4 @@ void aoenet_xmit(struct sk_buff *);
 int is_aoe_netif(struct net_device *ifp);
 int set_aoe_iflist(const char __user *str, size_t size);
 
-u64 mac_addr(char addr[6]);
+unsigned long long mac_addr(char addr[6]);
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index e10a7f3..7168d3d 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -33,8 +33,7 @@ static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
 
 	if (t == NULL)
 		return snprintf(page, PAGE_SIZE, "none\n");
-	return snprintf(page, PAGE_SIZE, "%012llx\n",
-			(unsigned long long)mac_addr(t->addr));
+	return snprintf(page, PAGE_SIZE, "%012llx\n", mac_addr(t->addr));
 }
 static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
 {
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 5e7daa1..1be5150 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -309,7 +309,8 @@ resend(struct aoedev *d, struct aoetgt *t, struct frame *f)
 		"%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);
+		mac_addr(h->src),
+		mac_addr(h->dst), t->nout);
 	aoechr_error(buf);
 
 	f->tag = n;
@@ -633,7 +634,7 @@ ataid_complete(struct aoedev *d, struct aoetgt *t, 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(t->addr),
+			mac_addr(t->addr),
 			d->aoemajor, d->aoeminor,
 			d->fw_ver, (long long)ssize);
 	d->ssize = ssize;
@@ -727,8 +728,7 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 	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));
+			d->aoemajor, d->aoeminor, mac_addr(hin->src));
 		spin_unlock_irqrestore(&d->lock, flags);
 		return;
 	}
@@ -1003,7 +1003,7 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 				"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));
+				mac_addr(t->addr));
 			ifp->maxbcnt = n;
 		}
 	}
diff --git a/drivers/block/aoe/aoenet.c b/drivers/block/aoe/aoenet.c
index 7a38a45..ada4a06 100644
--- a/drivers/block/aoe/aoenet.c
+++ b/drivers/block/aoe/aoenet.c
@@ -83,7 +83,7 @@ set_aoe_iflist(const char __user *user_str, size_t size)
 	return 0;
 }
 
-u64
+unsigned long long
 mac_addr(char addr[6])
 {
 	__be64 n = 0;
@@ -91,7 +91,7 @@ mac_addr(char addr[6])
 
 	memcpy(p + 2, addr, 6);	/* (sizeof addr != 6) */
 
-	return __be64_to_cpu(n);
+	return (unsigned long long) __be64_to_cpu(n);
 }
 
 void
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 04/13] clean up udev configuration example
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 02/13] handle multiple network paths to AoE device Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 03/13] mac_addr: avoid 64-bit arch compiler warnings Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 05/13] eliminate goto and improve readability Ed L. Cashin
                   ` (8 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

This patch adds a known default location for the udev configuration
file and uses the more recent "==" syntax for SUBSYSTEM and KERNEL.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 Documentation/aoe/udev-install.sh |    5 ++++-
 Documentation/aoe/udev.txt        |   15 ++++++++-------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/Documentation/aoe/udev-install.sh b/Documentation/aoe/udev-install.sh
index 6449911..15e86f5 100644
--- a/Documentation/aoe/udev-install.sh
+++ b/Documentation/aoe/udev-install.sh
@@ -23,7 +23,10 @@ fi
 # /etc/udev/rules.d
 #
 rules_d="`sed -n '/^udev_rules=/{ s!udev_rules=!!; s!\"!!g; p; }' $conf`"
-if test -z "$rules_d" || test ! -d "$rules_d"; then
+if test -z "$rules_d" ; then
+	rules_d=/etc/udev/rules.d
+fi
+if test ! -d "$rules_d"; then
 	echo "$me Error: cannot find udev rules directory" 1>&2
 	exit 1
 fi
diff --git a/Documentation/aoe/udev.txt b/Documentation/aoe/udev.txt
index a7ed1dc..17e76c4 100644
--- a/Documentation/aoe/udev.txt
+++ b/Documentation/aoe/udev.txt
@@ -1,6 +1,7 @@
 # These rules tell udev what device nodes to create for aoe support.
-# They may be installed along the following lines (adjusted to what
-# you see on your system).
+# They may be installed along the following lines.  Check the section
+# 8 udev manpage to see whether your udev supports SUBSYSTEM, and
+# whether it uses one or two equal signs for SUBSYSTEM and KERNEL.
 # 
 #   ecashin@makki ~$ su
 #   Password:
@@ -15,10 +16,10 @@
 #  
 
 # aoe char devices
-SUBSYSTEM="aoe", KERNEL="discover",	NAME="etherd/%k", GROUP="disk", MODE="0220"
-SUBSYSTEM="aoe", KERNEL="err",		NAME="etherd/%k", GROUP="disk", MODE="0440"
-SUBSYSTEM="aoe", KERNEL="interfaces",	NAME="etherd/%k", GROUP="disk", MODE="0220"
-SUBSYSTEM="aoe", KERNEL="revalidate",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="discover",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="err",	NAME="etherd/%k", GROUP="disk", MODE="0440"
+SUBSYSTEM=="aoe", KERNEL=="interfaces",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="revalidate",	NAME="etherd/%k", GROUP="disk", MODE="0220"
 
 # aoe block devices     
-KERNEL="etherd*",       NAME="%k", GROUP="disk"
+KERNEL=="etherd*",       NAME="%k", GROUP="disk"
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 05/13] eliminate goto and improve readability
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (2 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 04/13] clean up udev configuration example Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 06/13] user can ask driver to forget previously detected devices Ed L. Cashin
                   ` (7 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

Adam Richter suggested eliminating this goto.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoechr.c |   69 +++++++++++++++++++++----------------------
 1 files changed, 34 insertions(+), 35 deletions(-)

diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 1a5c4b5..4a3889d 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -194,52 +194,51 @@ aoechr_read(struct file *filp, char __user *buf, size_t cnt, loff_t *off)
 	ulong flags;
 
 	n = (unsigned long) filp->private_data;
-	switch (n) {
-	case MINOR_ERR:
-		spin_lock_irqsave(&emsgs_lock, flags);
-loop:
-		em = emsgs + emsgs_head_idx;
-		if ((em->flags & EMFL_VALID) == 0) {
-			if (filp->f_flags & O_NDELAY) {
-				spin_unlock_irqrestore(&emsgs_lock, flags);
-				return -EAGAIN;
-			}
-			nblocked_emsgs_readers++;
+	if (n != MINOR_ERR)
+		return -EFAULT;
+
+	spin_lock_irqsave(&emsgs_lock, flags);
 
+	for (;;) {
+		em = emsgs + emsgs_head_idx;
+		if ((em->flags & EMFL_VALID) != 0)
+			break;
+		if (filp->f_flags & O_NDELAY) {
 			spin_unlock_irqrestore(&emsgs_lock, flags);
+			return -EAGAIN;
+		}
+		nblocked_emsgs_readers++;
+
+		spin_unlock_irqrestore(&emsgs_lock, flags);
 
-			n = down_interruptible(&emsgs_sema);
+		n = down_interruptible(&emsgs_sema);
 
-			spin_lock_irqsave(&emsgs_lock, flags);
+		spin_lock_irqsave(&emsgs_lock, flags);
 
-			nblocked_emsgs_readers--;
+		nblocked_emsgs_readers--;
 
-			if (n) {
-				spin_unlock_irqrestore(&emsgs_lock, flags);
-				return -ERESTARTSYS;
-			}
-			goto loop;
-		}
-		if (em->len > cnt) {
+		if (n) {
 			spin_unlock_irqrestore(&emsgs_lock, flags);
-			return -EAGAIN;
+			return -ERESTARTSYS;
 		}
-		mp = em->msg;
-		len = em->len;
-		em->msg = NULL;
-		em->flags &= ~EMFL_VALID;
+	}
+	if (em->len > cnt) {
+		spin_unlock_irqrestore(&emsgs_lock, flags);
+		return -EAGAIN;
+	}
+	mp = em->msg;
+	len = em->len;
+	em->msg = NULL;
+	em->flags &= ~EMFL_VALID;
 
-		emsgs_head_idx++;
-		emsgs_head_idx %= ARRAY_SIZE(emsgs);
+	emsgs_head_idx++;
+	emsgs_head_idx %= ARRAY_SIZE(emsgs);
 
-		spin_unlock_irqrestore(&emsgs_lock, flags);
+	spin_unlock_irqrestore(&emsgs_lock, flags);
 
-		n = copy_to_user(buf, mp, len);
-		kfree(mp);
-		return n == 0 ? len : -EFAULT;
-	default:
-		return -EFAULT;
-	}
+	n = copy_to_user(buf, mp, len);
+	kfree(mp);
+	return n == 0 ? len : -EFAULT;
 }
 
 static const struct file_operations aoe_fops = {
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 06/13] user can ask driver to forget previously detected devices
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (3 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 05/13] eliminate goto and improve readability Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 07/13] dynamically allocate a capped number of skbs when necessary Ed L. Cashin
                   ` (6 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

When an AoE device is detected, the kernel is informed, and a new
block device is created.  If the device is unused, the block device
corresponding to remote device that is no longer available may be
removed from the system by telling the aoe driver to "flush" its list
of devices.

Without this patch, software like GPFS and LVM may attempt to read
from AoE devices that were discovered earlier but are no longer
present, blocking until the I/O attempt times out.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 Documentation/aoe/mkdevs.sh |    2 +
 Documentation/aoe/udev.txt  |    1 +
 drivers/block/aoe/aoe.h     |    1 +
 drivers/block/aoe/aoechr.c  |    5 ++
 drivers/block/aoe/aoedev.c  |   87 +++++++++++++++++++++++++++++++++---------
 5 files changed, 77 insertions(+), 19 deletions(-)

diff --git a/Documentation/aoe/mkdevs.sh b/Documentation/aoe/mkdevs.sh
index 97374aa..44c0ab7 100644
--- a/Documentation/aoe/mkdevs.sh
+++ b/Documentation/aoe/mkdevs.sh
@@ -29,6 +29,8 @@ rm -f $dir/interfaces
 mknod -m 0200 $dir/interfaces c $MAJOR 4
 rm -f $dir/revalidate
 mknod -m 0200 $dir/revalidate c $MAJOR 5
+rm -f $dir/flush
+mknod -m 0200 $dir/flush c $MAJOR 6
 
 export n_partitions
 mkshelf=`echo $0 | sed 's!mkdevs!mkshelf!'`
diff --git a/Documentation/aoe/udev.txt b/Documentation/aoe/udev.txt
index 17e76c4..8686e78 100644
--- a/Documentation/aoe/udev.txt
+++ b/Documentation/aoe/udev.txt
@@ -20,6 +20,7 @@ SUBSYSTEM=="aoe", KERNEL=="discover",	NAME="etherd/%k", GROUP="disk", MODE="0220
 SUBSYSTEM=="aoe", KERNEL=="err",	NAME="etherd/%k", GROUP="disk", MODE="0440"
 SUBSYSTEM=="aoe", KERNEL=="interfaces",	NAME="etherd/%k", GROUP="disk", MODE="0220"
 SUBSYSTEM=="aoe", KERNEL=="revalidate",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="flush",	NAME="etherd/%k", GROUP="disk", MODE="0220"
 
 # aoe block devices     
 KERNEL=="etherd*",       NAME="%k", GROUP="disk"
diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index aecaac3..2248ab2 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -191,6 +191,7 @@ struct aoedev *aoedev_by_aoeaddr(int maj, int min);
 struct aoedev *aoedev_by_sysminor_m(ulong sysminor);
 void aoedev_downdev(struct aoedev *d);
 int aoedev_isbusy(struct aoedev *d);
+int aoedev_flush(const char __user *str, size_t size);
 
 int aoenet_init(void);
 void aoenet_exit(void);
diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 4a3889d..166f54f 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -15,6 +15,7 @@ enum {
 	MINOR_DISCOVER,
 	MINOR_INTERFACES,
 	MINOR_REVALIDATE,
+	MINOR_FLUSH,
 	MSGSZ = 2048,
 	NMSG = 100,		/* message backlog to retain */
 };
@@ -43,6 +44,7 @@ static struct aoe_chardev chardevs[] = {
 	{ MINOR_DISCOVER, "discover" },
 	{ MINOR_INTERFACES, "interfaces" },
 	{ MINOR_REVALIDATE, "revalidate" },
+	{ MINOR_FLUSH, "flush" },
 };
 
 static int
@@ -158,6 +160,9 @@ aoechr_write(struct file *filp, const char __user *buf, size_t cnt, loff_t *offp
 		break;
 	case MINOR_REVALIDATE:
 		ret = revalidate(buf, cnt);
+		break;
+	case MINOR_FLUSH:
+		ret = aoedev_flush(buf, cnt);
 	}
 	if (ret == 0)
 		ret = cnt;
diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index a4d625a..e26f6f4 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -9,6 +9,10 @@
 #include <linux/netdevice.h>
 #include "aoe.h"
 
+static void dummy_timer(ulong);
+static void aoedev_freedev(struct aoedev *);
+static void freetgt(struct aoetgt *t);
+
 static struct aoedev *devlist;
 static spinlock_t devlist_lock;
 
@@ -108,6 +112,70 @@ aoedev_downdev(struct aoedev *d)
 	d->flags &= ~DEVFL_UP;
 }
 
+static void
+aoedev_freedev(struct aoedev *d)
+{
+	struct aoetgt **t, **e;
+
+	if (d->gd) {
+		aoedisk_rm_sysfs(d);
+		del_gendisk(d->gd);
+		put_disk(d->gd);
+	}
+	t = d->targets;
+	e = t + NTARGETS;
+	for (; t < e && *t; t++)
+		freetgt(*t);
+	if (d->bufpool)
+		mempool_destroy(d->bufpool);
+	kfree(d);
+}
+
+int
+aoedev_flush(const char __user *str, size_t cnt)
+{
+	ulong flags;
+	struct aoedev *d, **dd;
+	struct aoedev *rmd = NULL;
+	char buf[16];
+	int all = 0;
+
+	if (cnt >= 3) {
+		if (cnt > sizeof buf)
+			cnt = sizeof buf;
+		if (copy_from_user(buf, str, cnt))
+			return -EFAULT;
+		all = !strncmp(buf, "all", 3);
+	}
+
+	flush_scheduled_work();
+	spin_lock_irqsave(&devlist_lock, flags);
+	dd = &devlist;
+	while ((d = *dd)) {
+		spin_lock(&d->lock);
+		if ((!all && (d->flags & DEVFL_UP))
+		|| (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
+		|| d->nopen) {
+			spin_unlock(&d->lock);
+			dd = &d->next;
+			continue;
+		}
+		*dd = d->next;
+		aoedev_downdev(d);
+		d->flags |= DEVFL_TKILL;
+		spin_unlock(&d->lock);
+		d->next = rmd;
+		rmd = d;
+	}
+	spin_unlock_irqrestore(&devlist_lock, flags);
+	while ((d = rmd)) {
+		rmd = d->next;
+		del_timer_sync(&d->timer);
+		aoedev_freedev(d);	/* must be able to sleep */
+	}
+	return 0;
+}
+
 /* find it or malloc it */
 struct aoedev *
 aoedev_by_sysminor_m(ulong sysminor)
@@ -161,25 +229,6 @@ freetgt(struct aoetgt *t)
 	kfree(t);
 }
 
-static void
-aoedev_freedev(struct aoedev *d)
-{
-	struct aoetgt **t, **e;
-
-	if (d->gd) {
-		aoedisk_rm_sysfs(d);
-		del_gendisk(d->gd);
-		put_disk(d->gd);
-	}
-	t = d->targets;
-	e = t + NTARGETS;
-	for (; t < e && *t; t++)
-		freetgt(*t);
-	if (d->bufpool)
-		mempool_destroy(d->bufpool);
-	kfree(d);
-}
-
 void
 aoedev_exit(void)
 {
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 07/13] dynamically allocate a capped number of skbs when necessary
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (4 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 06/13] user can ask driver to forget previously detected devices Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 08/13] only install new AoE device once Ed L. Cashin
                   ` (5 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

What this Patch Does

  Even before this recent series of 12 patches to 2.6.22-rc4, the aoe
  driver was reusing a small set of skbs that were allocated once and
  were only used for outbound AoE commands.

  The network layer cannot be allowed to put_page on the data that is
  still associated with a bio we haven't returned to the block layer,
  so the aoe driver (even before the patch under discussion) is still
  the owner of skbs that have been handed to the network layer for
  transmission.  We need to keep track of these skbs so that we can
  free them, but by tracking them, we can also easily re-use them.

  The new patch was a response to the behavior of certain network
  drivers.  We cannot reuse an skb that the network driver still has
  in its transmit ring.  Network drivers can defer transmit ring
  cleanup and then use the state in the skb to determine how many data
  segments to clean up in its transmit ring.  The tg3 driver is one
  driver that behaves in this way.

  When the network driver defers cleanup of its transmit ring, the aoe
  driver can find itself in a situation where it would like to send an
  AoE command, and the AoE target is ready for more work, but the
  network driver still has all of the pre-allocated skbs.  In that
  case, the new patch just calls alloc_skb, as you'd expect.

  We don't want to get carried away, though.  We try not to do
  excessive allocation in the write path, so we cap the number of skbs
  we dynamically allocate.

  Probably calling it a "dynamic pool" is misleading.  We were already
  trying to use a small fixed-size set of pre-allocated skbs before
  this patch, and this patch just provides a little headroom (with a
  ceiling, though) to accomodate network drivers that hang onto skbs,
  by allocating when needed.  The d->skbpool_hd list of allocated skbs
  is necessary so that we can free them later.

  We didn't notice the need for this headroom until AoE targets got
  fast enough.

Alternatives

  If the network layer never did a put_page on the pages in the bio's
  we get from the block layer, then it would be possible for us to
  hand skbs to the network layer and forget about them, allowing the
  network layer to free skbs itself (and thereby calling our own
  skb->destructor callback function if we needed that).  In that case
  we could get rid of the pre-allocated skbs and also the
  d->skbpool_hd, instead just calling alloc_skb every time we wanted
  to transmit a packet.  The slab allocator would effectively maintain
  the list of skbs.

  Besides a loss of CPU cache locality, the main concern with that
  approach the danger that it would increase the likelihood of
  deadlock when VM is trying to free pages by writing dirty data from
  the page cache through the aoe driver out to persistent storage on
  an AoE device.  Right now we have a situation where we have
  pre-allocation that corresponds to how much we use, which seems
  ideal.

  Of course, there's still the separate issue of receiving the packets
  that tell us that a write has successfully completed on the AoE
  target.  When memory is low and VM is using AoE to flush dirty data
  to free up pages, it would be perfect if there were a way for us to
  register a fast callback that could recognize write command
  completion responses.  But I don't think the current problems with
  the receive side of the situation are a justification for
  exacerbating the problem on the transmit side.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoe.h    |    5 ++
 drivers/block/aoe/aoecmd.c |  117 +++++++++++++++++++++++++++++++-------------
 drivers/block/aoe/aoedev.c |   52 +++++++++++++++++---
 3 files changed, 133 insertions(+), 41 deletions(-)

diff --git a/drivers/block/aoe/aoe.h b/drivers/block/aoe/aoe.h
index 2248ab2..67ef4d7 100644
--- a/drivers/block/aoe/aoe.h
+++ b/drivers/block/aoe/aoe.h
@@ -89,6 +89,7 @@ enum {
 	MIN_BUFS = 16,
 	NTARGETS = 8,
 	NAOEIFS = 8,
+	NSKBPOOLMAX = 128,
 
 	TIMERTICK = HZ / 10,
 	MINTIMER = HZ >> 2,
@@ -138,6 +139,7 @@ struct aoetgt {
 	u16 useme;
 	ulong lastwadj;		/* last window adjustment */
 	int wpkts, rpkts;
+	int dataref;
 };
 
 struct aoedev {
@@ -159,6 +161,9 @@ struct aoedev {
 	spinlock_t lock;
 	struct sk_buff *sendq_hd; /* packets needing to be sent, list head */
 	struct sk_buff *sendq_tl;
+	struct sk_buff *skbpool_hd;
+	struct sk_buff *skbpool_tl;
+	int nskbpool;
 	mempool_t *bufpool;	/* for deadlock-free Buf allocation */
 	struct list_head bufq;	/* queue of bios to work on */
 	struct buf *inprocess;	/* the one we're currently working on */
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 1be5150..b49e06e 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -106,45 +106,104 @@ ifrotate(struct aoetgt *t)
 	}
 }
 
+static void
+skb_pool_put(struct aoedev *d, struct sk_buff *skb)
+{
+	if (!d->skbpool_hd)
+		d->skbpool_hd = skb;
+	else
+		d->skbpool_tl->next = skb;
+	d->skbpool_tl = skb;
+}
+
+static struct sk_buff *
+skb_pool_get(struct aoedev *d)
+{
+	struct sk_buff *skb;
+
+	skb = d->skbpool_hd;
+	if (skb && atomic_read(&skb_shinfo(skb)->dataref) == 1) {
+		d->skbpool_hd = skb->next;
+		skb->next = NULL;
+		return skb;
+	}
+	if (d->nskbpool < NSKBPOOLMAX
+	&& (skb = new_skb(ETH_ZLEN))) {
+		d->nskbpool++;
+		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;
+	struct frame *f, *e, *rf;
 	struct aoetgt **t;
-	ulong n;
+	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->targets;
-	do {
-		if (t != d->htgt
-		&& (*t)->ifp->nd
-		&& (*t)->nout < (*t)->maxout) {
-			n = (*t)->nframes;
+	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 + n;
+			e = f + (*t)->nframes;
 			for (; f < e; f++) {
 				if (f->tag != FREETAG)
 					continue;
-				if (atomic_read(&skb_shinfo(f->skb)->dataref)
+				skb = f->skb;
+				if (!skb
+				&& !(f->skb = skb = new_skb(ETH_ZLEN)))
+					continue;
+				if (atomic_read(&skb_shinfo(skb)->dataref)
 					!= 1) {
-					n--;
+					if (!rf)
+						rf = f;
 					continue;
 				}
-				skb_shinfo(f->skb)->nr_frags = 0;
-				f->skb->data_len = 0;
-				skb_trim(f->skb, 0);
+gotone:				skb_shinfo(skb)->nr_frags = skb->data_len = 0;
+				skb_trim(skb, 0);
 				d->tgt = t;
 				ifrotate(*t);
 				return f;
 			}
-			if (n == 0)	/* slow polling network card */
+			/* 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++;
-	} while (t < &d->targets[NTARGETS] && *t);
+		if (t >= &d->targets[NTARGETS] || !*t)
+			t = d->targets;
+	}
 	return NULL;
 }
 
@@ -894,33 +953,23 @@ addtgt(struct aoedev *d, char *addr, ulong nframes)
 		return NULL;
 
 	t = kcalloc(1, sizeof *t, GFP_ATOMIC);
+	if (!t)
+		return NULL;
 	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
-	if (!t || !f)
-		goto bail;
+	if (!f) {
+		kfree(t);
+		return NULL;
+	}
+
 	t->nframes = nframes;
 	t->frames = f;
 	e = f + nframes;
-	for (; f < e; f++) {
+	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
diff --git a/drivers/block/aoe/aoedev.c b/drivers/block/aoe/aoedev.c
index e26f6f4..839a964 100644
--- a/drivers/block/aoe/aoedev.c
+++ b/drivers/block/aoe/aoedev.c
@@ -7,11 +7,13 @@
 #include <linux/hdreg.h>
 #include <linux/blkdev.h>
 #include <linux/netdevice.h>
+#include <linux/delay.h>
 #include "aoe.h"
 
 static void dummy_timer(ulong);
 static void aoedev_freedev(struct aoedev *);
-static void freetgt(struct aoetgt *t);
+static void freetgt(struct aoedev *d, struct aoetgt *t);
+static void skbpoolfree(struct aoedev *d);
 
 static struct aoedev *devlist;
 static spinlock_t devlist_lock;
@@ -125,9 +127,10 @@ aoedev_freedev(struct aoedev *d)
 	t = d->targets;
 	e = t + NTARGETS;
 	for (; t < e && *t; t++)
-		freetgt(*t);
+		freetgt(d, *t);
 	if (d->bufpool)
 		mempool_destroy(d->bufpool);
+	skbpoolfree(d);
 	kfree(d);
 }
 
@@ -176,6 +179,43 @@ aoedev_flush(const char __user *str, size_t cnt)
 	return 0;
 }
 
+/* I'm not really sure that this is a realistic problem, but if the
+network driver goes gonzo let's just leak memory after complaining. */
+static void
+skbfree(struct sk_buff *skb)
+{
+	enum { Sms = 100, Tms = 3*1000};
+	int i = Tms / Sms;
+
+	if (skb == NULL)
+		return;
+	while (atomic_read(&skb_shinfo(skb)->dataref) != 1 && i-- > 0)
+		msleep(Sms);
+	if (i <= 0) {
+		printk(KERN_ERR
+			"aoe: %s holds ref: %s\n",
+			skb->dev ? skb->dev->name : "netif",
+			"cannot free skb -- memory leaked.");
+		return;
+	}
+	skb_shinfo(skb)->nr_frags = skb->data_len = 0;
+	skb_trim(skb, 0);
+	dev_kfree_skb(skb);
+}
+
+static void
+skbpoolfree(struct aoedev *d)
+{
+	struct sk_buff *skb;
+
+	while ((skb = d->skbpool_hd)) {
+		d->skbpool_hd = skb->next;
+		skb->next = NULL;
+		skbfree(skb);
+	}
+	d->skbpool_tl = NULL;
+}
+
 /* find it or malloc it */
 struct aoedev *
 aoedev_by_sysminor_m(ulong sysminor)
@@ -215,16 +255,14 @@ aoedev_by_sysminor_m(ulong sysminor)
 }
 
 static void
-freetgt(struct aoetgt *t)
+freetgt(struct aoedev *d, struct aoetgt *t)
 {
 	struct frame *f, *e;
 
 	f = t->frames;
 	e = f + t->nframes;
-	for (; f < e; f++) {
-		skb_shinfo(f->skb)->nr_frags = 0;
-		dev_kfree_skb(f->skb);
-	}
+	for (; f < e; f++)
+		skbfree(f->skb);
 	kfree(t->frames);
 	kfree(t);
 }
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 08/13] only install new AoE device once
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (5 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 07/13] dynamically allocate a capped number of skbs when necessary Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 09/13] remove race between use and initialization of locks Ed L. Cashin
                   ` (4 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

An aoe driver user who had about 70 AoE targets found that he was
hitting a BUG in sysfs_create_file because the aoe driver was trying
to tell the kernel about an AoE device more than once.  Each AoE
device was reachable by several local network interfaces, and multiple
ATA device indentify responses were returning from that single device.

This patch eliminates a race condition so that aoe always informs the
block layer of a new AoE device once in the presence of multiple
incoming ATA device identify responses.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoecmd.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index b49e06e..7a96183 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -698,6 +698,8 @@ ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
 			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) {
 		d->gd->capacity = ssize;
 		d->flags |= DEVFL_NEWSIZE;
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 09/13] remove race between use and initialization of locks
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (6 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 08/13] only install new AoE device once Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 10/13] add module parameter for users who need more outstanding I/O Ed L. Cashin
                   ` (3 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

Alexey Dobriyan noticed a race in the initialization of the dynamic
locks in ...

  Message-ID: <20070325190221.GA5308@martell.zuzino.mipt.ru>

Andrew Morton commented that these locks should be initialized at
compile time, so this patch does that.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoechr.c |    6 ++----
 1 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 166f54f..0ce9bda 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -35,8 +35,8 @@ struct ErrMsg {
 
 static struct ErrMsg emsgs[NMSG];
 static int emsgs_head_idx, emsgs_tail_idx;
-static struct semaphore emsgs_sema;
-static spinlock_t emsgs_lock;
+static __DECLARE_SEMAPHORE_GENERIC(emsgs_sema, 0);
+static DEFINE_SPINLOCK(emsgs_lock);
 static int nblocked_emsgs_readers;
 static struct class *aoe_class;
 static struct aoe_chardev chardevs[] = {
@@ -264,8 +264,6 @@ aoechr_init(void)
 		printk(KERN_ERR "aoe: can't register char device\n");
 		return n;
 	}
-	sema_init(&emsgs_sema, 0);
-	spin_lock_init(&emsgs_lock);
 	aoe_class = class_create(THIS_MODULE, "aoe");
 	if (IS_ERR(aoe_class)) {
 		unregister_chrdev(AOE_MAJOR, "aoechr");
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 10/13] add module parameter for users who need more outstanding I/O
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (7 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 09/13] remove race between use and initialization of locks Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 11/13] remove extra space in prototypes for consistency Ed L. Cashin
                   ` (2 subsequent siblings)
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

An AoE target provides an estimate of the number of outstanding
commands that the AoE initiator can send before getting a response.
The aoe_maxout parameter provides a way to set an even lower limit.
It will not allow a user to use more outstanding commands than the
target permits.  If a user discovers a problem with a large setting,
this parameter provides a way for us to work with them to debug the
problem.  We expect to improve the dynamic window sizing algorithm and
drop this parameter.  For the time being, it is a debugging aid.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoecmd.c |   10 +++++++---
 1 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 7a96183..e92d885 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -18,6 +18,11 @@ 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)
 {
@@ -984,7 +989,6 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 	struct aoeif *ifp;
 	ulong flags, sysminor, aoemajor;
 	struct sk_buff *sl;
-	enum { MAXFRAMES = 16 };
 	u16 n;
 
 	h = (struct aoe_hdr *) skb_mac_header(skb);
@@ -1009,8 +1013,8 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 	}
 
 	n = be16_to_cpu(ch->bufcnt);
-	if (n > MAXFRAMES)	/* keep it reasonable */
-		n = MAXFRAMES;
+	if (n > aoe_maxout)	/* keep it reasonable */
+		n = aoe_maxout;
 
 	d = aoedev_by_sysminor_m(sysminor);
 	if (d == NULL) {
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 11/13] remove extra space in prototypes for consistency
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (8 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 10/13] add module parameter for users who need more outstanding I/O Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 12/13] the aoeminor doesn't need a long format Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 13/13] make error messages more specific Ed L. Cashin
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

Remove extra space in prototypes for consistency.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoeblk.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 7168d3d..98ab170 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -15,7 +15,7 @@
 
 static struct kmem_cache *buf_pool_cache;
 
-static ssize_t aoedisk_show_state(struct gendisk * disk, char *page)
+static ssize_t aoedisk_show_state(struct gendisk *disk, char *page)
 {
 	struct aoedev *d = disk->private_data;
 
@@ -26,7 +26,7 @@ static ssize_t aoedisk_show_state(struct gendisk * disk, char *page)
 			(d->nopen && !(d->flags & DEVFL_UP)) ? ",closewait" : "");
 	/* I'd rather see nopen exported so we can ditch closewait */
 }
-static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
+static ssize_t aoedisk_show_mac(struct gendisk *disk, char *page)
 {
 	struct aoedev *d = disk->private_data;
 	struct aoetgt *t = d->targets[0];
@@ -35,7 +35,7 @@ static ssize_t aoedisk_show_mac(struct gendisk * disk, char *page)
 		return snprintf(page, PAGE_SIZE, "none\n");
 	return snprintf(page, PAGE_SIZE, "%012llx\n", mac_addr(t->addr));
 }
-static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
+static ssize_t aoedisk_show_netif(struct gendisk *disk, char *page)
 {
 	struct aoedev *d = disk->private_data;
 	struct net_device *nds[8], **nd, **nnd, **ne;
@@ -71,7 +71,7 @@ static ssize_t aoedisk_show_netif(struct gendisk * disk, char *page)
 	return p-page;
 }
 /* firmware version */
-static ssize_t aoedisk_show_fwver(struct gendisk * disk, char *page)
+static ssize_t aoedisk_show_fwver(struct gendisk *disk, char *page)
 {
 	struct aoedev *d = disk->private_data;
 
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 12/13] the aoeminor doesn't need a long format
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (9 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 11/13] remove extra space in prototypes for consistency Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  2007-12-07 17:48 ` [PATCH 13/13] make error messages more specific Ed L. Cashin
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

The aoedev aoeminor member doesn't need a long format.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoeblk.c |    7 ++++---
 drivers/block/aoe/aoecmd.c |    5 +++--
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 98ab170..b78a8ef 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -203,7 +203,7 @@ aoeblk_make_request(struct request_queue *q, struct bio *bio)
 	spin_lock_irqsave(&d->lock, flags);
 
 	if ((d->flags & DEVFL_UP) == 0) {
-		printk(KERN_INFO "aoe: device %ld.%ld is not up\n",
+		printk(KERN_INFO "aoe: device %ld.%d is not up\n",
 			d->aoemajor, d->aoeminor);
 		spin_unlock_irqrestore(&d->lock, flags);
 		mempool_free(buf, d->bufpool);
@@ -256,14 +256,15 @@ aoeblk_gdalloc(void *vp)
 
 	gd = alloc_disk(AOE_PARTITIONS);
 	if (gd == NULL) {
-		printk(KERN_ERR "aoe: cannot allocate disk structure for %ld.%ld\n",
+		printk(KERN_ERR
+			"aoe: cannot allocate disk structure for %ld.%d\n",
 			d->aoemajor, d->aoeminor);
 		goto err;
 	}
 
 	d->bufpool = mempool_create_slab_pool(MIN_BUFS, buf_pool_cache);
 	if (d->bufpool == NULL) {
-		printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%ld\n",
+		printk(KERN_ERR "aoe: cannot allocate bufpool for %ld.%d\n",
 			d->aoemajor, d->aoeminor);
 		goto err_disk;
 	}
diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index e92d885..bcea36c 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -697,7 +697,8 @@ ataid_complete(struct aoedev *d, struct aoetgt *t, unsigned char *id)
 	}
 
 	if (d->ssize != ssize)
-		printk(KERN_INFO "aoe: %012llx e%lu.%lu v%04x has %llu sectors\n",
+		printk(KERN_INFO
+			"aoe: %012llx e%ld.%d v%04x has %llu sectors\n",
 			mac_addr(t->addr),
 			d->aoemajor, d->aoeminor,
 			d->fw_ver, (long long)ssize);
@@ -822,7 +823,7 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 
 	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",
+			"aoe: ata error cmd=%2.2Xh stat=%2.2Xh from e%ld.%d\n",
 			ahout->cmdstat, ahin->cmdstat,
 			d->aoemajor, d->aoeminor);
 		if (buf)
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 13/13] make error messages more specific
  2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
                   ` (10 preceding siblings ...)
  2007-12-07 17:48 ` [PATCH 12/13] the aoeminor doesn't need a long format Ed L. Cashin
@ 2007-12-07 17:48 ` Ed L. Cashin
  11 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-07 17:48 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Greg KH

Andrew Morton pointed out that the "too many targets" message in patch
2 could be printed for failing GFP_ATOMIC allocations.  This patch
makes the messages more specific.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 drivers/block/aoe/aoecmd.c |   15 +++++++--------
 1 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index bcea36c..1e37cf6 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -957,15 +957,17 @@ addtgt(struct aoedev *d, char *addr, ulong nframes)
 	for (; tt < te && *tt; tt++)
 		;
 
-	if (tt == te)
+	if (tt == te) {
+		printk(KERN_INFO
+			"aoe: device addtgt failure; too many targets\n");
 		return NULL;
-
+	}
 	t = kcalloc(1, sizeof *t, GFP_ATOMIC);
-	if (!t)
-		return NULL;
 	f = kcalloc(nframes, sizeof *f, GFP_ATOMIC);
-	if (!f) {
+	if (!t || !f) {
+		kfree(f);
 		kfree(t);
+		printk(KERN_INFO "aoe: cannot allocate memory to add target\n");
 		return NULL;
 	}
 
@@ -1029,9 +1031,6 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 	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;
 		}
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

* [PATCH 04/13] clean up udev configuration example
  2007-12-20 22:15 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
@ 2007-12-20 22:15 ` Ed L. Cashin
  0 siblings, 0 replies; 14+ messages in thread
From: Ed L. Cashin @ 2007-12-20 22:15 UTC (permalink / raw)
  To: linux-kernel; +Cc: Ed L. Cashin, Andrew Morton

This patch adds a known default location for the udev configuration
file and uses the more recent "==" syntax for SUBSYSTEM and KERNEL.

Signed-off-by: Ed L. Cashin <ecashin@coraid.com>
---
 Documentation/aoe/udev-install.sh |    5 ++++-
 Documentation/aoe/udev.txt        |   15 ++++++++-------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/Documentation/aoe/udev-install.sh b/Documentation/aoe/udev-install.sh
index 6449911..15e86f5 100644
--- a/Documentation/aoe/udev-install.sh
+++ b/Documentation/aoe/udev-install.sh
@@ -23,7 +23,10 @@ fi
 # /etc/udev/rules.d
 #
 rules_d="`sed -n '/^udev_rules=/{ s!udev_rules=!!; s!\"!!g; p; }' $conf`"
-if test -z "$rules_d" || test ! -d "$rules_d"; then
+if test -z "$rules_d" ; then
+	rules_d=/etc/udev/rules.d
+fi
+if test ! -d "$rules_d"; then
 	echo "$me Error: cannot find udev rules directory" 1>&2
 	exit 1
 fi
diff --git a/Documentation/aoe/udev.txt b/Documentation/aoe/udev.txt
index a7ed1dc..17e76c4 100644
--- a/Documentation/aoe/udev.txt
+++ b/Documentation/aoe/udev.txt
@@ -1,6 +1,7 @@
 # These rules tell udev what device nodes to create for aoe support.
-# They may be installed along the following lines (adjusted to what
-# you see on your system).
+# They may be installed along the following lines.  Check the section
+# 8 udev manpage to see whether your udev supports SUBSYSTEM, and
+# whether it uses one or two equal signs for SUBSYSTEM and KERNEL.
 # 
 #   ecashin@makki ~$ su
 #   Password:
@@ -15,10 +16,10 @@
 #  
 
 # aoe char devices
-SUBSYSTEM="aoe", KERNEL="discover",	NAME="etherd/%k", GROUP="disk", MODE="0220"
-SUBSYSTEM="aoe", KERNEL="err",		NAME="etherd/%k", GROUP="disk", MODE="0440"
-SUBSYSTEM="aoe", KERNEL="interfaces",	NAME="etherd/%k", GROUP="disk", MODE="0220"
-SUBSYSTEM="aoe", KERNEL="revalidate",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="discover",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="err",	NAME="etherd/%k", GROUP="disk", MODE="0440"
+SUBSYSTEM=="aoe", KERNEL=="interfaces",	NAME="etherd/%k", GROUP="disk", MODE="0220"
+SUBSYSTEM=="aoe", KERNEL=="revalidate",	NAME="etherd/%k", GROUP="disk", MODE="0220"
 
 # aoe block devices     
-KERNEL="etherd*",       NAME="%k", GROUP="disk"
+KERNEL=="etherd*",       NAME="%k", GROUP="disk"
-- 
1.5.3.4


^ permalink raw reply related	[flat|nested] 14+ messages in thread

end of thread, other threads:[~2007-12-20 22:17 UTC | newest]

Thread overview: 14+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2007-12-07 17:47 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
2007-12-07 17:48 ` [PATCH 02/13] handle multiple network paths to AoE device Ed L. Cashin
2007-12-07 17:48 ` [PATCH 03/13] mac_addr: avoid 64-bit arch compiler warnings Ed L. Cashin
2007-12-07 17:48 ` [PATCH 04/13] clean up udev configuration example Ed L. Cashin
2007-12-07 17:48 ` [PATCH 05/13] eliminate goto and improve readability Ed L. Cashin
2007-12-07 17:48 ` [PATCH 06/13] user can ask driver to forget previously detected devices Ed L. Cashin
2007-12-07 17:48 ` [PATCH 07/13] dynamically allocate a capped number of skbs when necessary Ed L. Cashin
2007-12-07 17:48 ` [PATCH 08/13] only install new AoE device once Ed L. Cashin
2007-12-07 17:48 ` [PATCH 09/13] remove race between use and initialization of locks Ed L. Cashin
2007-12-07 17:48 ` [PATCH 10/13] add module parameter for users who need more outstanding I/O Ed L. Cashin
2007-12-07 17:48 ` [PATCH 11/13] remove extra space in prototypes for consistency Ed L. Cashin
2007-12-07 17:48 ` [PATCH 12/13] the aoeminor doesn't need a long format Ed L. Cashin
2007-12-07 17:48 ` [PATCH 13/13] make error messages more specific Ed L. Cashin
2007-12-20 22:15 [PATCH 01/13] bring driver version number to 47 Ed L. Cashin
2007-12-20 22:15 ` [PATCH 04/13] clean up udev configuration example Ed L. Cashin

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