[Patch 16/18] enable XPNET to handle more than 64 partitions

From: Dean Nelson
Date: Fri Jun 06 2008 - 13:00:43 EST


Enable XPNET to support more than 64 partitions.

Signed-off-by: Dean Nelson <dcn@xxxxxxx>

---

drivers/misc/sgi-xp/xpc.h | 3
drivers/misc/sgi-xp/xpc_channel.c | 197 +-------------------------------
drivers/misc/sgi-xp/xpc_main.c | 2
drivers/misc/sgi-xp/xpc_sn2.c | 205 ++++++++++++++++++++++++++++++++--
4 files changed, 204 insertions(+), 203 deletions(-)

Index: linux-2.6/drivers/misc/sgi-xp/xpnet.c
===================================================================
--- linux-2.6.orig/drivers/misc/sgi-xp/xpnet.c 2008-05-28 10:48:52.000000000 -0500
+++ linux-2.6/drivers/misc/sgi-xp/xpnet.c 2008-05-30 13:21:33.065013335 -0500
@@ -21,7 +21,6 @@
*/

#include <linux/module.h>
-#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/ioport.h>
@@ -32,8 +31,6 @@
#include <linux/mii.h>
#include <linux/smp.h>
#include <linux/string.h>
-#include <asm/sn/io.h>
-#include <asm/sn/sn_sal.h>
#include <asm/atomic.h>
#include "xp.h"

@@ -104,7 +101,6 @@ struct xpnet_message {
* then be released.
*/
struct xpnet_pending_msg {
- struct list_head free_list;
struct sk_buff *skb;
atomic_t use_count;
};
@@ -120,7 +116,7 @@ struct net_device *xpnet_device;
* When we are notified of other partitions activating, we add them to
* our bitmask of partitions to which we broadcast.
*/
-static u64 xpnet_broadcast_partitions;
+static unsigned long *xpnet_broadcast_partitions;
/* protect above */
static DEFINE_SPINLOCK(xpnet_broadcast_lock);

@@ -140,16 +136,13 @@ static DEFINE_SPINLOCK(xpnet_broadcast_l
#define XPNET_DEF_MTU (0x8000UL)

/*
- * The partition id is encapsulated in the MAC address. The following
- * define locates the octet the partid is in.
+ * The partid is encapsulated in the MAC address beginning in the following
+ * octet and it consists of two octets.
*/
-#define XPNET_PARTID_OCTET 1
-#define XPNET_LICENSE_OCTET 2
+#define XPNET_PARTID_OCTET 2
+
+/* Define the XPNET debug device structures to be used with dev_dbg() et al */

-/*
- * Define the XPNET debug device structure that is to be used with dev_dbg(),
- * dev_err(), dev_warn(), and dev_info().
- */
struct device_driver xpnet_dbg_name = {
.name = "xpnet"
};
@@ -231,7 +224,7 @@ xpnet_receive(short partid, int channel,
(void *)msg->buf_pa, msg->size);

ret = xp_remote_memcpy((void *)((u64)skb->data &
- ~(L1_CACHE_BYTES - 1)),
+ ~(L1_CACHE_BYTES - 1)),
(void *)msg->buf_pa, msg->size);

if (ret != xpSuccess) {
@@ -283,8 +276,6 @@ static void
xpnet_connection_activity(enum xp_retval reason, short partid, int channel,
void *data, void *key)
{
- long bp;
-
DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
DBUG_ON(channel != XPC_NET_CHANNEL);

@@ -297,31 +288,28 @@ xpnet_connection_activity(enum xp_retval

case xpConnected: /* connection completed to a partition */
spin_lock_bh(&xpnet_broadcast_lock);
- xpnet_broadcast_partitions |= 1UL << (partid - 1);
- bp = xpnet_broadcast_partitions;
+ __set_bit(partid, xpnet_broadcast_partitions);
spin_unlock_bh(&xpnet_broadcast_lock);

netif_carrier_on(xpnet_device);

- dev_dbg(xpnet, "%s connection created to partition %d; "
- "xpnet_broadcast_partitions=0x%lx\n",
- xpnet_device->name, partid, bp);
+ dev_dbg(xpnet, "%s connected to partition %d\n",
+ xpnet_device->name, partid);
break;

default:
spin_lock_bh(&xpnet_broadcast_lock);
- xpnet_broadcast_partitions &= ~(1UL << (partid - 1));
- bp = xpnet_broadcast_partitions;
+ __clear_bit(partid, xpnet_broadcast_partitions);
spin_unlock_bh(&xpnet_broadcast_lock);

- if (bp == 0)
+ if (bitmap_empty((unsigned long *)xpnet_broadcast_partitions,
+ xp_max_npartitions)) {
netif_carrier_off(xpnet_device);
+ }

- dev_dbg(xpnet, "%s disconnected from partition %d; "
- "xpnet_broadcast_partitions=0x%lx\n",
- xpnet_device->name, partid, bp);
+ dev_dbg(xpnet, "%s disconnected from partition %d\n",
+ xpnet_device->name, partid);
break;
-
}
}

@@ -424,36 +412,72 @@ xpnet_send_completed(enum xp_retval reas
}
}

+static void
+xpnet_send(struct sk_buff *skb, struct xpnet_pending_msg *queued_msg,
+ u64 start_addr, u64 end_addr, u16 embedded_bytes, int dest_partid)
+{
+ u8 msg_buffer[XPNET_MSG_SIZE];
+ struct xpnet_message *msg = (struct xpnet_message *)&msg_buffer;
+ enum xp_retval ret;
+
+ msg->embedded_bytes = embedded_bytes;
+ if (unlikely(embedded_bytes != 0)) {
+ msg->version = XPNET_VERSION_EMBED;
+ dev_dbg(xpnet, "calling memcpy(0x%p, 0x%p, 0x%lx)\n",
+ &msg->data, skb->data, (size_t)embedded_bytes);
+ skb_copy_from_linear_data(skb, &msg->data,
+ (size_t)embedded_bytes);
+ } else {
+ msg->version = XPNET_VERSION;
+ }
+ msg->magic = XPNET_MAGIC;
+ msg->size = end_addr - start_addr;
+ msg->leadin_ignore = (u64)skb->data - start_addr;
+ msg->tailout_ignore = end_addr - (u64)skb_tail_pointer(skb);
+ msg->buf_pa = __pa(start_addr);
+
+ dev_dbg(xpnet, "sending XPC message to %d:%d\n"
+ KERN_DEBUG "msg->buf_pa=0x%lx, msg->size=%u, "
+ "msg->leadin_ignore=%u, msg->tailout_ignore=%u\n",
+ dest_partid, XPC_NET_CHANNEL, msg->buf_pa, msg->size,
+ msg->leadin_ignore, msg->tailout_ignore);
+
+ atomic_inc(&queued_msg->use_count);
+
+ ret = xpc_send_notify(dest_partid, XPC_NET_CHANNEL, XPC_NOWAIT, msg,
+ XPNET_MSG_SIZE, xpnet_send_completed, queued_msg);
+ if (unlikely(ret != xpSuccess))
+ atomic_dec(&queued_msg->use_count);
+}
+
/*
* Network layer has formatted a packet (skb) and is ready to place it
* "on the wire". Prepare and send an xpnet_message to all partitions
* which have connected with us and are targets of this packet.
*
* MAC-NOTE: For the XPNET driver, the MAC address contains the
- * destination partition_id. If the destination partition id word
- * is 0xff, this packet is to broadcast to all partitions.
+ * destination partid. If the destination partid octets are 0xffff,
+ * this packet is to be broadcast to all connected partitions.
*/
static int
xpnet_dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct xpnet_pending_msg *queued_msg;
- enum xp_retval ret;
- u8 msg_buffer[XPNET_MSG_SIZE];
- struct xpnet_message *msg = (struct xpnet_message *)&msg_buffer[0];
u64 start_addr, end_addr;
- long dp;
- u8 second_mac_octet;
short dest_partid;
- struct xpnet_dev_private *priv;
- u16 embedded_bytes;
-
- priv = (struct xpnet_dev_private *)dev->priv;
+ struct xpnet_dev_private *priv = (struct xpnet_dev_private *)dev->priv;
+ u16 embedded_bytes = 0;

dev_dbg(xpnet, ">skb->head=0x%p skb->data=0x%p skb->tail=0x%p "
"skb->end=0x%p skb->len=%d\n", (void *)skb->head,
(void *)skb->data, skb_tail_pointer(skb), skb_end_pointer(skb),
skb->len);

+ if (skb->data[0] == 0x33) {
+ dev_kfree_skb(skb);
+ return 0; /* nothing needed to be done */
+ }
+
/*
* The xpnet_pending_msg tracks how many outstanding
* xpc_send_notifies are relying on this skb. When none
@@ -465,7 +489,6 @@ xpnet_dev_hard_start_xmit(struct sk_buff
"packet\n", sizeof(struct xpnet_pending_msg));

priv->stats.tx_errors++;
-
return -ENOMEM;
}

@@ -474,7 +497,6 @@ xpnet_dev_hard_start_xmit(struct sk_buff
end_addr = L1_CACHE_ALIGN((u64)skb_tail_pointer(skb));

/* calculate how many bytes to embed in the XPC message */
- embedded_bytes = 0;
if (unlikely(skb->len <= XPNET_MSG_DATA_MAX)) {
/* skb->data does fit so embed */
embedded_bytes = skb->len;
@@ -490,78 +512,28 @@ xpnet_dev_hard_start_xmit(struct sk_buff
atomic_set(&queued_msg->use_count, 1);
queued_msg->skb = skb;

- second_mac_octet = skb->data[XPNET_PARTID_OCTET];
- if (second_mac_octet == 0xff) {
+ if (skb->data[0] == 0xff) {
/* we are being asked to broadcast to all partitions */
- dp = xpnet_broadcast_partitions;
- } else if (second_mac_octet != 0) {
- dp = xpnet_broadcast_partitions &
- (1UL << (second_mac_octet - 1));
- } else {
- /* 0 is an invalid partid. Ignore */
- dp = 0;
- }
- dev_dbg(xpnet, "destination Partitions mask (dp) = 0x%lx\n", dp);
-
- /*
- * If we wanted to allow promiscuous mode to work like an
- * unswitched network, this would be a good point to OR in a
- * mask of partitions which should be receiving all packets.
- */
-
- /*
- * Main send loop.
- */
- for (dest_partid = 0; dp && dest_partid < xp_max_npartitions;
- dest_partid++) {
+ for_each_bit(dest_partid, xpnet_broadcast_partitions,
+ xp_max_npartitions) {

- if (!(dp & (1UL << (dest_partid - 1)))) {
- /* not destined for this partition */
- continue;
+ xpnet_send(skb, queued_msg, start_addr, end_addr,
+ embedded_bytes, dest_partid);
}
+ } else {
+ dest_partid = (short)skb->data[XPNET_PARTID_OCTET + 1];
+ dest_partid |= (short)skb->data[XPNET_PARTID_OCTET + 0] << 8;

- /* remove this partition from the destinations mask */
- dp &= ~(1UL << (dest_partid - 1));
-
- /* found a partition to send to */
+ if (dest_partid >= 0 &&
+ dest_partid < xp_max_npartitions &&
+ test_bit(dest_partid, xpnet_broadcast_partitions) != 0) {

- msg->embedded_bytes = embedded_bytes;
- if (unlikely(embedded_bytes != 0)) {
- msg->version = XPNET_VERSION_EMBED;
- dev_dbg(xpnet, "calling memcpy(0x%p, 0x%p, 0x%lx)\n",
- &msg->data, skb->data, (size_t)embedded_bytes);
- skb_copy_from_linear_data(skb, &msg->data,
- (size_t)embedded_bytes);
- } else {
- msg->version = XPNET_VERSION;
- }
- msg->magic = XPNET_MAGIC;
- msg->size = end_addr - start_addr;
- msg->leadin_ignore = (u64)skb->data - start_addr;
- msg->tailout_ignore = end_addr - (u64)skb_tail_pointer(skb);
- msg->buf_pa = __pa(start_addr);
-
- dev_dbg(xpnet, "sending XPC message to %d:%d\n"
- KERN_DEBUG "msg->buf_pa=0x%lx, msg->size=%u, "
- "msg->leadin_ignore=%u, msg->tailout_ignore=%u\n",
- dest_partid, XPC_NET_CHANNEL, msg->buf_pa, msg->size,
- msg->leadin_ignore, msg->tailout_ignore);
-
- atomic_inc(&queued_msg->use_count);
-
- ret = xpc_send_notify(dest_partid, XPC_NET_CHANNEL, XPC_NOWAIT,
- &msg, sizeof(msg) + embedded_bytes - 1,
- xpnet_send_completed, queued_msg);
- if (unlikely(ret != xpSuccess)) {
- atomic_dec(&queued_msg->use_count);
- continue;
+ xpnet_send(skb, queued_msg, start_addr, end_addr,
+ embedded_bytes, dest_partid);
}
}

if (atomic_dec_return(&queued_msg->use_count) == 0) {
- dev_dbg(xpnet, "no partitions to receive packet destined for "
- "%d\n", dest_partid);
-
dev_kfree_skb(skb);
kfree(queued_msg);
}
@@ -589,23 +561,28 @@ xpnet_dev_tx_timeout(struct net_device *
static int __init
xpnet_init(void)
{
- int i;
- u32 license_num;
- int result = -ENOMEM;
+ int result;

- if (!ia64_platform_is("sn2"))
+ if (!is_shub() && !is_uv())
return -ENODEV;

dev_info(xpnet, "registering network device %s\n", XPNET_DEVICE_NAME);

+ xpnet_broadcast_partitions = kzalloc(BITS_TO_LONGS(xp_max_npartitions) *
+ sizeof(long), GFP_KERNEL);
+ if (xpnet_broadcast_partitions == NULL)
+ return -ENOMEM;
+
/*
* use ether_setup() to init the majority of our device
* structure and then override the necessary pieces.
*/
xpnet_device = alloc_netdev(sizeof(struct xpnet_dev_private),
XPNET_DEVICE_NAME, ether_setup);
- if (xpnet_device == NULL)
+ if (xpnet_device == NULL) {
+ kfree(xpnet_broadcast_partitions);
return -ENOMEM;
+ }

netif_carrier_off(xpnet_device);

@@ -623,14 +600,10 @@ xpnet_init(void)
* MAC addresses. We chose the first octet of the MAC to be unlikely
* to collide with any vendor's officially issued MAC.
*/
- xpnet_device->dev_addr[0] = 0xfe;
- xpnet_device->dev_addr[XPNET_PARTID_OCTET] = sn_partition_id;
- license_num = sn_partition_serial_number_val();
- for (i = 3; i >= 0; i--) {
- xpnet_device->dev_addr[XPNET_LICENSE_OCTET + i] =
- license_num & 0xff;
- license_num = license_num >> 8;
- }
+ xpnet_device->dev_addr[0] = 0x02; /* locally administered, no OUI */
+
+ xpnet_device->dev_addr[XPNET_PARTID_OCTET + 1] = sn_partition_id;
+ xpnet_device->dev_addr[XPNET_PARTID_OCTET + 0] = (sn_partition_id >> 8);

/*
* ether_setup() sets this to a multicast device. We are
@@ -646,8 +619,10 @@ xpnet_init(void)
xpnet_device->features = NETIF_F_NO_CSUM;

result = register_netdev(xpnet_device);
- if (result != 0)
+ if (result != 0) {
free_netdev(xpnet_device);
+ kfree(xpnet_broadcast_partitions);
+ }

return result;
}
@@ -661,8 +636,8 @@ xpnet_exit(void)
xpnet_device[0].name);

unregister_netdev(xpnet_device);
-
free_netdev(xpnet_device);
+ kfree(xpnet_broadcast_partitions);
}

module_exit(xpnet_exit);
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