sgi-xpc: implement opencomplete messaging
sgi-xpc has a window of failure where an open message can be sent and a
subsequent data message can get lost. We have added a new message
(opencomplete) which closes that window.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/misc/sgi-xp/xpc_channel.c b/drivers/misc/sgi-xp/xpc_channel.c
index 99a2534..2eb3abf 100644
--- a/drivers/misc/sgi-xp/xpc_channel.c
+++ b/drivers/misc/sgi-xp/xpc_channel.c
@@ -3,7 +3,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
- * Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved.
+ * Copyright (c) 2004-2009 Silicon Graphics, Inc. All Rights Reserved.
*/
/*
@@ -44,10 +44,10 @@
if (ret != xpSuccess)
XPC_DISCONNECT_CHANNEL(ch, ret, irq_flags);
+ else
+ ch->flags |= XPC_C_SETUP;
- ch->flags |= XPC_C_SETUP;
-
- if (ch->flags & (XPC_C_CONNECTED | XPC_C_DISCONNECTING))
+ if (ch->flags & XPC_C_DISCONNECTING)
return;
}
@@ -59,14 +59,18 @@
if (!(ch->flags & XPC_C_ROPENREPLY))
return;
- ch->flags = (XPC_C_CONNECTED | XPC_C_SETUP); /* clear all else */
+ if (!(ch->flags & XPC_C_OPENCOMPLETE)) {
+ ch->flags |= (XPC_C_OPENCOMPLETE | XPC_C_CONNECTED);
+ xpc_send_chctl_opencomplete(ch, irq_flags);
+ }
+
+ if (!(ch->flags & XPC_C_ROPENCOMPLETE))
+ return;
dev_info(xpc_chan, "channel %d to partition %d connected\n",
ch->number, ch->partid);
- spin_unlock_irqrestore(&ch->lock, *irq_flags);
- xpc_create_kthreads(ch, 1, 0);
- spin_lock_irqsave(&ch->lock, *irq_flags);
+ ch->flags = (XPC_C_CONNECTED | XPC_C_SETUP); /* clear all else */
}
/*
@@ -184,6 +188,7 @@
struct xpc_channel *ch = &part->channels[ch_number];
enum xp_retval reason;
enum xp_retval ret;
+ int create_kthread = 0;
spin_lock_irqsave(&ch->lock, irq_flags);
@@ -196,8 +201,7 @@
* has had a chance to see that the channel is disconnected.
*/
ch->delayed_chctl_flags |= chctl_flags;
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
if (chctl_flags & XPC_CHCTL_CLOSEREQUEST) {
@@ -239,8 +243,7 @@
XPC_CHCTL_CLOSEREQUEST;
spin_unlock(&part->chctl_lock);
}
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
XPC_SET_REASON(ch, 0, 0);
@@ -250,7 +253,8 @@
ch->flags |= (XPC_C_CONNECTING | XPC_C_ROPENREQUEST);
}
- chctl_flags &= ~(XPC_CHCTL_OPENREQUEST | XPC_CHCTL_OPENREPLY);
+ chctl_flags &= ~(XPC_CHCTL_OPENREQUEST | XPC_CHCTL_OPENREPLY |
+ XPC_CHCTL_OPENCOMPLETE);
/*
* The meaningful CLOSEREQUEST connection state fields are:
@@ -269,8 +273,7 @@
XPC_DISCONNECT_CHANNEL(ch, reason, &irq_flags);
DBUG_ON(chctl_flags & XPC_CHCTL_CLOSEREPLY);
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
xpc_process_disconnect(ch, &irq_flags);
@@ -283,8 +286,7 @@
if (ch->flags & XPC_C_DISCONNECTED) {
DBUG_ON(part->act_state != XPC_P_AS_DEACTIVATING);
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
DBUG_ON(!(ch->flags & XPC_C_CLOSEREQUEST));
@@ -299,8 +301,7 @@
XPC_CHCTL_CLOSEREPLY;
spin_unlock(&part->chctl_lock);
}
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
ch->flags |= XPC_C_RCLOSEREPLY;
@@ -320,14 +321,12 @@
if (part->act_state == XPC_P_AS_DEACTIVATING ||
(ch->flags & XPC_C_ROPENREQUEST)) {
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_WDISCONNECT)) {
ch->delayed_chctl_flags |= XPC_CHCTL_OPENREQUEST;
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
DBUG_ON(!(ch->flags & (XPC_C_DISCONNECTED |
XPC_C_OPENREQUEST)));
@@ -341,8 +340,7 @@
*/
if (args->entry_size == 0 || args->local_nentries == 0) {
/* assume OPENREQUEST was delayed by mistake */
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
ch->flags |= (XPC_C_ROPENREQUEST | XPC_C_CONNECTING);
@@ -352,8 +350,7 @@
if (args->entry_size != ch->entry_size) {
XPC_DISCONNECT_CHANNEL(ch, xpUnequalMsgSizes,
&irq_flags);
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
} else {
ch->entry_size = args->entry_size;
@@ -375,15 +372,13 @@
args->local_msgqueue_pa, args->local_nentries,
args->remote_nentries, ch->partid, ch->number);
- if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_DISCONNECTED)) {
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
- }
+ if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_DISCONNECTED))
+ goto out;
+
if (!(ch->flags & XPC_C_OPENREQUEST)) {
XPC_DISCONNECT_CHANNEL(ch, xpOpenCloseError,
&irq_flags);
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
DBUG_ON(!(ch->flags & XPC_C_ROPENREQUEST));
@@ -403,8 +398,7 @@
ret = xpc_save_remote_msgqueue_pa(ch, args->local_msgqueue_pa);
if (ret != xpSuccess) {
XPC_DISCONNECT_CHANNEL(ch, ret, &irq_flags);
- spin_unlock_irqrestore(&ch->lock, irq_flags);
- return;
+ goto out;
}
ch->flags |= XPC_C_ROPENREPLY;
@@ -430,7 +424,36 @@
xpc_process_connect(ch, &irq_flags);
}
+ if (chctl_flags & XPC_CHCTL_OPENCOMPLETE) {
+
+ dev_dbg(xpc_chan, "XPC_CHCTL_OPENCOMPLETE received from "
+ "partid=%d, channel=%d\n", ch->partid, ch->number);
+
+ if (ch->flags & (XPC_C_DISCONNECTING | XPC_C_DISCONNECTED))
+ goto out;
+
+ if (!(ch->flags & XPC_C_OPENREQUEST) ||
+ !(ch->flags & XPC_C_OPENREPLY)) {
+ XPC_DISCONNECT_CHANNEL(ch, xpOpenCloseError,
+ &irq_flags);
+ goto out;
+ }
+
+ DBUG_ON(!(ch->flags & XPC_C_ROPENREQUEST));
+ DBUG_ON(!(ch->flags & XPC_C_ROPENREPLY));
+ DBUG_ON(!(ch->flags & XPC_C_CONNECTED));
+
+ ch->flags |= XPC_C_ROPENCOMPLETE;
+
+ xpc_process_connect(ch, &irq_flags);
+ create_kthread = 1;
+ }
+
+out:
spin_unlock_irqrestore(&ch->lock, irq_flags);
+
+ if (create_kthread)
+ xpc_create_kthreads(ch, 1, 0);
}
/*
@@ -564,10 +587,6 @@
if (!(ch_flags & XPC_C_OPENREQUEST)) {
DBUG_ON(ch_flags & XPC_C_SETUP);
(void)xpc_connect_channel(ch);
- } else {
- spin_lock_irqsave(&ch->lock, irq_flags);
- xpc_process_connect(ch, &irq_flags);
- spin_unlock_irqrestore(&ch->lock, irq_flags);
}
continue;
}