aoe: support more AoE addresses with dynamic block device minor numbers

The ATA over Ethernet protocol uses a major (shelf) and minor (slot)
address to identify a particular storage target.  These changes remove an
artificial limitation the aoe driver imposes on the use of AoE addresses.
For example, without these changes, the slot address has a maximum of 15,
but users commonly use slot numbers much greater than that.

The AoE shelf and slot address space is often used sparsely.  Instead of
using a static mapping between AoE addresses and the block device minor
number, the block device minor numbers are now allocated on demand.

Signed-off-by: Ed Cashin <ecashin@coraid.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 17 deletions

diff --git a/drivers/block/aoe/aoecmd.c b/drivers/block/aoe/aoecmd.c
index 39dacdb..94e810c 100644
--- a/drivers/block/aoe/aoecmd.c
+++ b/drivers/block/aoe/aoecmd.c
@@ -1149,7 +1149,7 @@ aoecmd_ata_rsp(struct sk_buff *skb)
 
 	h = (struct aoe_hdr *) skb->data;
 	aoemajor = be16_to_cpu(get_unaligned(&h->major));
-	d = aoedev_by_aoeaddr(aoemajor, h->minor);
+	d = aoedev_by_aoeaddr(aoemajor, h->minor, 0);
 	if (d == NULL) {
 		snprintf(ebuf, sizeof ebuf, "aoecmd_ata_rsp: ata response "
 			"for unknown device %d.%d\n",
@@ -1330,7 +1330,7 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 	struct aoe_hdr *h;
 	struct aoe_cfghdr *ch;
 	struct aoetgt *t;
-	ulong flags, sysminor, aoemajor;
+	ulong flags, aoemajor;
 	struct sk_buff *sl;
 	struct sk_buff_head queue;
 	u16 n;
@@ -1349,18 +1349,15 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 			"Check shelf dip switches.\n");
 		return;
 	}
-	if (h->minor >= NPERSHELF) {
-		pr_err("aoe: e%ld.%d %s, %d\n",
-			aoemajor, h->minor,
-			"slot number larger than the maximum",
-			NPERSHELF-1);
+	if (aoemajor > AOE_MAXSHELF) {
+		pr_info("aoe: e%ld.%d: shelf number too large\n",
+			aoemajor, (int) h->minor);
 		return;
 	}
 
-	sysminor = SYSMINOR(aoemajor, h->minor);
-	if (sysminor * AOE_PARTITIONS + AOE_PARTITIONS > MINORMASK) {
-		printk(KERN_INFO "aoe: e%ld.%d: minor number too large\n",
-			aoemajor, (int) h->minor);
+	d = aoedev_by_aoeaddr(aoemajor, h->minor, 1);
+	if (d == NULL) {
+		pr_info("aoe: device allocation failure\n");
 		return;
 	}
 
@@ -1368,12 +1365,6 @@ aoecmd_cfg_rsp(struct sk_buff *skb)
 	if (n > aoe_maxout)	/* keep it reasonable */
 		n = aoe_maxout;
 
-	d = aoedev_by_sysminor_m(sysminor);
-	if (d == NULL) {
-		printk(KERN_INFO "aoe: device sysminor_m failure\n");
-		return;
-	}
-
 	spin_lock_irqsave(&d->lock, flags);
 
 	t = gettgt(d, h->src);