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path: root/drivers/misc/sgi-xp/xpc_channel.c
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Diffstat (limited to 'drivers/misc/sgi-xp/xpc_channel.c')
-rw-r--r--drivers/misc/sgi-xp/xpc_channel.c315
1 files changed, 2 insertions, 313 deletions
diff --git a/drivers/misc/sgi-xp/xpc_channel.c b/drivers/misc/sgi-xp/xpc_channel.c
index 8081e8155dff..26c5e12c1220 100644
--- a/drivers/misc/sgi-xp/xpc_channel.c
+++ b/drivers/misc/sgi-xp/xpc_channel.c
@@ -1165,7 +1165,7 @@ xpc_disconnect_callout(struct xpc_channel *ch, enum xp_retval reason)
* Wait for a message entry to become available for the specified channel,
* but don't wait any longer than 1 jiffy.
*/
-static enum xp_retval
+enum xp_retval
xpc_allocate_msg_wait(struct xpc_channel *ch)
{
enum xp_retval ret;
@@ -1193,96 +1193,6 @@ xpc_allocate_msg_wait(struct xpc_channel *ch)
/*
* Allocate an entry for a message from the message queue associated with the
- * specified channel.
- */
-static enum xp_retval
-xpc_allocate_msg(struct xpc_channel *ch, u32 flags,
- struct xpc_msg **address_of_msg)
-{
- struct xpc_msg *msg;
- enum xp_retval ret;
- s64 put;
-
- /* this reference will be dropped in xpc_send_msg() */
- xpc_msgqueue_ref(ch);
-
- if (ch->flags & XPC_C_DISCONNECTING) {
- xpc_msgqueue_deref(ch);
- return ch->reason;
- }
- if (!(ch->flags & XPC_C_CONNECTED)) {
- xpc_msgqueue_deref(ch);
- return xpNotConnected;
- }
-
- /*
- * Get the next available message entry from the local message queue.
- * If none are available, we'll make sure that we grab the latest
- * GP values.
- */
- ret = xpTimeout;
-
- while (1) {
-
- put = ch->w_local_GP.put;
- rmb(); /* guarantee that .put loads before .get */
- if (put - ch->w_remote_GP.get < ch->local_nentries) {
-
- /* There are available message entries. We need to try
- * to secure one for ourselves. We'll do this by trying
- * to increment w_local_GP.put as long as someone else
- * doesn't beat us to it. If they do, we'll have to
- * try again.
- */
- if (cmpxchg(&ch->w_local_GP.put, put, put + 1) == put) {
- /* we got the entry referenced by put */
- break;
- }
- continue; /* try again */
- }
-
- /*
- * There aren't any available msg entries at this time.
- *
- * In waiting for a message entry to become available,
- * we set a timeout in case the other side is not
- * sending completion IPIs. This lets us fake an IPI
- * that will cause the IPI handler to fetch the latest
- * GP values as if an IPI was sent by the other side.
- */
- if (ret == xpTimeout)
- xpc_IPI_send_local_msgrequest(ch);
-
- if (flags & XPC_NOWAIT) {
- xpc_msgqueue_deref(ch);
- return xpNoWait;
- }
-
- ret = xpc_allocate_msg_wait(ch);
- if (ret != xpInterrupted && ret != xpTimeout) {
- xpc_msgqueue_deref(ch);
- return ret;
- }
- }
-
- /* get the message's address and initialize it */
- msg = (struct xpc_msg *)((u64)ch->local_msgqueue +
- (put % ch->local_nentries) * ch->msg_size);
-
- DBUG_ON(msg->flags != 0);
- msg->number = put;
-
- dev_dbg(xpc_chan, "w_local_GP.put changed to %ld; msg=0x%p, "
- "msg_number=%ld, partid=%d, channel=%d\n", put + 1,
- (void *)msg, msg->number, ch->partid, ch->number);
-
- *address_of_msg = msg;
-
- return xpSuccess;
-}
-
-/*
- * Allocate an entry for a message from the message queue associated with the
* specified channel. NOTE that this routine can sleep waiting for a message
* entry to become available. To not sleep, pass in the XPC_NOWAIT flag.
*
@@ -1318,144 +1228,6 @@ xpc_initiate_allocate(short partid, int ch_number, u32 flags, void **payload)
}
/*
- * Now we actually send the messages that are ready to be sent by advancing
- * the local message queue's Put value and then send an IPI to the recipient
- * partition.
- */
-static void
-xpc_send_msgs(struct xpc_channel *ch, s64 initial_put)
-{
- struct xpc_msg *msg;
- s64 put = initial_put + 1;
- int send_IPI = 0;
-
- while (1) {
-
- while (1) {
- if (put == ch->w_local_GP.put)
- break;
-
- msg = (struct xpc_msg *)((u64)ch->local_msgqueue +
- (put % ch->local_nentries) *
- ch->msg_size);
-
- if (!(msg->flags & XPC_M_READY))
- break;
-
- put++;
- }
-
- if (put == initial_put) {
- /* nothing's changed */
- break;
- }
-
- if (cmpxchg_rel(&ch->local_GP->put, initial_put, put) !=
- initial_put) {
- /* someone else beat us to it */
- DBUG_ON(ch->local_GP->put < initial_put);
- break;
- }
-
- /* we just set the new value of local_GP->put */
-
- dev_dbg(xpc_chan, "local_GP->put changed to %ld, partid=%d, "
- "channel=%d\n", put, ch->partid, ch->number);
-
- send_IPI = 1;
-
- /*
- * We need to ensure that the message referenced by
- * local_GP->put is not XPC_M_READY or that local_GP->put
- * equals w_local_GP.put, so we'll go have a look.
- */
- initial_put = put;
- }
-
- if (send_IPI)
- xpc_IPI_send_msgrequest(ch);
-}
-
-/*
- * Common code that does the actual sending of the message by advancing the
- * local message queue's Put value and sends an IPI to the partition the
- * message is being sent to.
- */
-static enum xp_retval
-xpc_send_msg(struct xpc_channel *ch, struct xpc_msg *msg, u8 notify_type,
- xpc_notify_func func, void *key)
-{
- enum xp_retval ret = xpSuccess;
- struct xpc_notify *notify = notify;
- s64 put, msg_number = msg->number;
-
- DBUG_ON(notify_type == XPC_N_CALL && func == NULL);
- DBUG_ON((((u64)msg - (u64)ch->local_msgqueue) / ch->msg_size) !=
- msg_number % ch->local_nentries);
- DBUG_ON(msg->flags & XPC_M_READY);
-
- if (ch->flags & XPC_C_DISCONNECTING) {
- /* drop the reference grabbed in xpc_allocate_msg() */
- xpc_msgqueue_deref(ch);
- return ch->reason;
- }
-
- if (notify_type != 0) {
- /*
- * Tell the remote side to send an ACK interrupt when the
- * message has been delivered.
- */
- msg->flags |= XPC_M_INTERRUPT;
-
- atomic_inc(&ch->n_to_notify);
-
- notify = &ch->notify_queue[msg_number % ch->local_nentries];
- notify->func = func;
- notify->key = key;
- notify->type = notify_type;
-
- /* >>> is a mb() needed here? */
-
- if (ch->flags & XPC_C_DISCONNECTING) {
- /*
- * An error occurred between our last error check and
- * this one. We will try to clear the type field from
- * the notify entry. If we succeed then
- * xpc_disconnect_channel() didn't already process
- * the notify entry.
- */
- if (cmpxchg(&notify->type, notify_type, 0) ==
- notify_type) {
- atomic_dec(&ch->n_to_notify);
- ret = ch->reason;
- }
-
- /* drop the reference grabbed in xpc_allocate_msg() */
- xpc_msgqueue_deref(ch);
- return ret;
- }
- }
-
- msg->flags |= XPC_M_READY;
-
- /*
- * The preceding store of msg->flags must occur before the following
- * load of ch->local_GP->put.
- */
- mb();
-
- /* see if the message is next in line to be sent, if so send it */
-
- put = ch->local_GP->put;
- if (put == msg_number)
- xpc_send_msgs(ch, put);
-
- /* drop the reference grabbed in xpc_allocate_msg() */
- xpc_msgqueue_deref(ch);
- return ret;
-}
-
-/*
* Send a message previously allocated using xpc_initiate_allocate() on the
* specified channel connected to the specified partition.
*
@@ -1586,66 +1358,6 @@ xpc_deliver_msg(struct xpc_channel *ch)
}
/*
- * Now we actually acknowledge the messages that have been delivered and ack'd
- * by advancing the cached remote message queue's Get value and if requested
- * send an IPI to the message sender's partition.
- */
-static void
-xpc_acknowledge_msgs(struct xpc_channel *ch, s64 initial_get, u8 msg_flags)
-{
- struct xpc_msg *msg;
- s64 get = initial_get + 1;
- int send_IPI = 0;
-
- while (1) {
-
- while (1) {
- if (get == ch->w_local_GP.get)
- break;
-
- msg = (struct xpc_msg *)((u64)ch->remote_msgqueue +
- (get % ch->remote_nentries) *
- ch->msg_size);
-
- if (!(msg->flags & XPC_M_DONE))
- break;
-
- msg_flags |= msg->flags;
- get++;
- }
-
- if (get == initial_get) {
- /* nothing's changed */
- break;
- }
-
- if (cmpxchg_rel(&ch->local_GP->get, initial_get, get) !=
- initial_get) {
- /* someone else beat us to it */
- DBUG_ON(ch->local_GP->get <= initial_get);
- break;
- }
-
- /* we just set the new value of local_GP->get */
-
- dev_dbg(xpc_chan, "local_GP->get changed to %ld, partid=%d, "
- "channel=%d\n", get, ch->partid, ch->number);
-
- send_IPI = (msg_flags & XPC_M_INTERRUPT);
-
- /*
- * We need to ensure that the message referenced by
- * local_GP->get is not XPC_M_DONE or that local_GP->get
- * equals w_local_GP.get, so we'll go have a look.
- */
- initial_get = get;
- }
-
- if (send_IPI)
- xpc_IPI_send_msgrequest(ch);
-}
-
-/*
* Acknowledge receipt of a delivered message.
*
* If a message has XPC_M_INTERRUPT set, send an interrupt to the partition
@@ -1668,35 +1380,12 @@ xpc_initiate_received(short partid, int ch_number, void *payload)
struct xpc_partition *part = &xpc_partitions[partid];
struct xpc_channel *ch;
struct xpc_msg *msg = XPC_MSG_ADDRESS(payload);
- s64 get, msg_number = msg->number;
DBUG_ON(partid < 0 || partid >= xp_max_npartitions);
DBUG_ON(ch_number < 0 || ch_number >= part->nchannels);
ch = &part->channels[ch_number];
-
- dev_dbg(xpc_chan, "msg=0x%p, msg_number=%ld, partid=%d, channel=%d\n",
- (void *)msg, msg_number, ch->partid, ch->number);
-
- DBUG_ON((((u64)msg - (u64)ch->remote_msgqueue) / ch->msg_size) !=
- msg_number % ch->remote_nentries);
- DBUG_ON(msg->flags & XPC_M_DONE);
-
- msg->flags |= XPC_M_DONE;
-
- /*
- * The preceding store of msg->flags must occur before the following
- * load of ch->local_GP->get.
- */
- mb();
-
- /*
- * See if this message is next in line to be acknowledged as having
- * been delivered.
- */
- get = ch->local_GP->get;
- if (get == msg_number)
- xpc_acknowledge_msgs(ch, get, msg->flags);
+ xpc_received_msg(ch, msg);
/* the call to xpc_msgqueue_ref() was done by xpc_deliver_msg() */
xpc_msgqueue_deref(ch);