firewire: fw_send_request_sync()

Share code between fw_send_request + wait_for_completion callers.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>

Addendum:
Removes an unnecessary struct and an ununsed retry loop.
Calls it fw_run_transaction() instead of fw_send_request_sync().
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Kristian Høgsberg <krh@redhat.com>

drivers/firewire/fw-card.c

@@ -189,39 +189,16 @@ static const char gap_count_table[] = {
 	63, 5, 7, 8, 10, 13, 16, 18, 21, 24, 26, 29, 32, 35, 37, 40
 };
 
-struct bm_data {
-	struct fw_transaction t;
-	struct {
-		__be32 arg;
-		__be32 data;
-	} lock;
-	u32 old;
-	int rcode;
-	struct completion done;
-};
-
-static void
-complete_bm_lock(struct fw_card *card, int rcode,
-		 void *payload, size_t length, void *data)
-{
-	struct bm_data *bmd = data;
-
-	if (rcode == RCODE_COMPLETE)
-		bmd->old = be32_to_cpu(*(__be32 *) payload);
-	bmd->rcode = rcode;
-	complete(&bmd->done);
-}
-
 static void
 fw_card_bm_work(struct work_struct *work)
 {
 	struct fw_card *card = container_of(work, struct fw_card, work.work);
 	struct fw_device *root_device;
 	struct fw_node *root_node, *local_node;
-	struct bm_data bmd;
 	unsigned long flags;
-	int root_id, new_root_id, irm_id, gap_count, generation, grace;
+	int root_id, new_root_id, irm_id, gap_count, generation, grace, rcode;
 	bool do_reset = false;
+	__be32 lock_data[2];
 
 	spin_lock_irqsave(&card->lock, flags);
 	local_node = card->local_node;
@@ -263,33 +240,28 @@ fw_card_bm_work(struct work_struct *work)
 			goto pick_me;
 		}
 
-		bmd.lock.arg = cpu_to_be32(0x3f);
-		bmd.lock.data = cpu_to_be32(local_node->node_id);
+		lock_data[0] = cpu_to_be32(0x3f);
+		lock_data[1] = cpu_to_be32(local_node->node_id);
 
 		spin_unlock_irqrestore(&card->lock, flags);
 
-		init_completion(&bmd.done);
-		fw_send_request(card, &bmd.t, TCODE_LOCK_COMPARE_SWAP,
-				irm_id, generation,
-				SCODE_100, CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID,
-				&bmd.lock, sizeof(bmd.lock),
-				complete_bm_lock, &bmd);
-		wait_for_completion(&bmd.done);
+		rcode = fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
+				irm_id, generation, SCODE_100,
+				CSR_REGISTER_BASE + CSR_BUS_MANAGER_ID,
+				lock_data, sizeof(lock_data));
 
-		if (bmd.rcode == RCODE_GENERATION) {
-			/*
-			 * Another bus reset happened. Just return,
-			 * the BM work has been rescheduled.
-			 */
+		if (rcode == RCODE_GENERATION)
+			/* Another bus reset, BM work has been rescheduled. */
 			goto out;
-		}
 
-		if (bmd.rcode == RCODE_COMPLETE && bmd.old != 0x3f)
+		if (rcode == RCODE_COMPLETE &&
+		    lock_data[0] != cpu_to_be32(0x3f))
 			/* Somebody else is BM, let them do the work. */
 			goto out;
 
 		spin_lock_irqsave(&card->lock, flags);
-		if (bmd.rcode != RCODE_COMPLETE) {
+
+		if (rcode != RCODE_COMPLETE) {
 			/*
 			 * The lock request failed, maybe the IRM
 			 * isn't really IRM capable after all. Let's

drivers/firewire/fw-device.c

@@ -381,46 +381,21 @@ static struct device_attribute fw_device_attributes[] = {
 	__ATTR_NULL,
 };
 
-struct read_quadlet_callback_data {
-	struct completion done;
-	int rcode;
-	u32 data;
-};
-
-static void
-complete_transaction(struct fw_card *card, int rcode,
-		     void *payload, size_t length, void *data)
-{
-	struct read_quadlet_callback_data *callback_data = data;
-
-	if (rcode == RCODE_COMPLETE)
-		callback_data->data = be32_to_cpu(*(__be32 *)payload);
-	callback_data->rcode = rcode;
-	complete(&callback_data->done);
-}
-
 static int
 read_rom(struct fw_device *device, int generation, int index, u32 *data)
 {
-	struct read_quadlet_callback_data callback_data;
-	struct fw_transaction t;
-	u64 offset;
+	int rcode;
 
 	/* device->node_id, accessed below, must not be older than generation */
 	smp_rmb();
 
-	init_completion(&callback_data.done);
-
-	offset = (CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4;
-	fw_send_request(device->card, &t, TCODE_READ_QUADLET_REQUEST,
+	rcode = fw_run_transaction(device->card, TCODE_READ_QUADLET_REQUEST,
 			device->node_id, generation, device->max_speed,
-			offset, NULL, 4, complete_transaction, &callback_data);
-
-	wait_for_completion(&callback_data.done);
-
-	*data = callback_data.data;
+			(CSR_REGISTER_BASE | CSR_CONFIG_ROM) + index * 4,
+			data, 4);
+	be32_to_cpus(data);
 
-	return callback_data.rcode;
+	return rcode;
 }
 
 #define READ_BIB_ROM_SIZE	256

drivers/firewire/fw-sbp2.c

@@ -621,25 +621,15 @@ sbp2_send_management_orb(struct sbp2_logical_unit *lu, int node_id,
 	return retval;
 }
 
-static void
-complete_agent_reset_write(struct fw_card *card, int rcode,
-			   void *payload, size_t length, void *done)
-{
-	complete(done);
-}
-
 static void sbp2_agent_reset(struct sbp2_logical_unit *lu)
 {
 	struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
-	DECLARE_COMPLETION_ONSTACK(done);
-	struct fw_transaction t;
-	static u32 z;
+	__be32 d = 0;
 
-	fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
-			lu->tgt->node_id, lu->generation, device->max_speed,
-			lu->command_block_agent_address + SBP2_AGENT_RESET,
-			&z, sizeof(z), complete_agent_reset_write, &done);
-	wait_for_completion(&done);
+	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
+			   lu->tgt->node_id, lu->generation, device->max_speed,
+			   lu->command_block_agent_address + SBP2_AGENT_RESET,
+			   &d, sizeof(d));
 }
 
 static void
@@ -653,7 +643,7 @@ static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 {
 	struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
 	struct fw_transaction *t;
-	static u32 z;
+	static __be32 d;
 
 	t = kmalloc(sizeof(*t), GFP_ATOMIC);
 	if (t == NULL)
@@ -662,7 +652,7 @@ static void sbp2_agent_reset_no_wait(struct sbp2_logical_unit *lu)
 	fw_send_request(device->card, t, TCODE_WRITE_QUADLET_REQUEST,
 			lu->tgt->node_id, lu->generation, device->max_speed,
 			lu->command_block_agent_address + SBP2_AGENT_RESET,
-			&z, sizeof(z), complete_agent_reset_write_no_wait, t);
+			&d, sizeof(d), complete_agent_reset_write_no_wait, t);
 }
 
 static void sbp2_set_generation(struct sbp2_logical_unit *lu, int generation)
@@ -823,13 +813,6 @@ static void sbp2_target_put(struct sbp2_target *tgt)
 	kref_put(&tgt->kref, sbp2_release_target);
 }
 
-static void
-complete_set_busy_timeout(struct fw_card *card, int rcode,
-			  void *payload, size_t length, void *done)
-{
-	complete(done);
-}
-
 /*
  * Write retransmit retry values into the BUSY_TIMEOUT register.
  * - The single-phase retry protocol is supported by all SBP-2 devices, but the
@@ -849,17 +832,12 @@ complete_set_busy_timeout(struct fw_card *card, int rcode,
 static void sbp2_set_busy_timeout(struct sbp2_logical_unit *lu)
 {
 	struct fw_device *device = fw_device(lu->tgt->unit->device.parent);
-	DECLARE_COMPLETION_ONSTACK(done);
-	struct fw_transaction t;
-	static __be32 busy_timeout;
-
-	busy_timeout = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
+	__be32 d = cpu_to_be32(SBP2_CYCLE_LIMIT | SBP2_RETRY_LIMIT);
 
-	fw_send_request(device->card, &t, TCODE_WRITE_QUADLET_REQUEST,
-			lu->tgt->node_id, lu->generation, device->max_speed,
-			CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT, &busy_timeout,
-			sizeof(busy_timeout), complete_set_busy_timeout, &done);
-	wait_for_completion(&done);
+	fw_run_transaction(device->card, TCODE_WRITE_QUADLET_REQUEST,
+			   lu->tgt->node_id, lu->generation, device->max_speed,
+			   CSR_REGISTER_BASE + CSR_BUSY_TIMEOUT,
+			   &d, sizeof(d));
 }
 
 static void sbp2_reconnect(struct work_struct *work);

drivers/firewire/fw-transaction.c

@@ -247,7 +247,7 @@ fw_fill_request(struct fw_packet *packet, int tcode, int tlabel,
  */
 void
 fw_send_request(struct fw_card *card, struct fw_transaction *t,
-		int tcode, int node_id, int generation, int speed,
+		int tcode, int destination_id, int generation, int speed,
 		unsigned long long offset,
 		void *payload, size_t length,
 		fw_transaction_callback_t callback, void *callback_data)
@@ -279,13 +279,14 @@ fw_send_request(struct fw_card *card, struct fw_transaction *t,
 	card->current_tlabel = (card->current_tlabel + 1) & 0x1f;
 	card->tlabel_mask |= (1 << tlabel);
 
-	t->node_id = node_id;
+	t->node_id = destination_id;
 	t->tlabel = tlabel;
 	t->callback = callback;
 	t->callback_data = callback_data;
 
-	fw_fill_request(&t->packet, tcode, t->tlabel, node_id, card->node_id,
-			generation, speed, offset, payload, length);
+	fw_fill_request(&t->packet, tcode, t->tlabel,
+			destination_id, card->node_id, generation,
+			speed, offset, payload, length);
 	t->packet.callback = transmit_complete_callback;
 
 	list_add_tail(&t->link, &card->transaction_list);
@@ -296,6 +297,45 @@ fw_send_request(struct fw_card *card, struct fw_transaction *t,
 }
 EXPORT_SYMBOL(fw_send_request);
 
+struct transaction_callback_data {
+	struct completion done;
+	void *payload;
+	int rcode;
+};
+
+static void transaction_callback(struct fw_card *card, int rcode,
+				 void *payload, size_t length, void *data)
+{
+	struct transaction_callback_data *d = data;
+
+	if (rcode == RCODE_COMPLETE)
+		memcpy(d->payload, payload, length);
+	d->rcode = rcode;
+	complete(&d->done);
+}
+
+/**
+ * fw_run_transaction - send request and sleep until transaction is completed
+ *
+ * Returns the RCODE.
+ */
+int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
+		int generation, int speed, unsigned long long offset,
+		void *data, size_t length)
+{
+	struct transaction_callback_data d;
+	struct fw_transaction t;
+
+	init_completion(&d.done);
+	d.payload = data;
+	fw_send_request(card, &t, tcode, destination_id, generation, speed,
+			offset, data, length, transaction_callback, &d);
+	wait_for_completion(&d.done);
+
+	return d.rcode;
+}
+EXPORT_SYMBOL(fw_run_transaction);
+
 static DEFINE_MUTEX(phy_config_mutex);
 static DECLARE_COMPLETION(phy_config_done);
 

drivers/firewire/fw-transaction.h

@@ -426,11 +426,14 @@ fw_core_initiate_bus_reset(struct fw_card *card, int short_reset);
 
 void
 fw_send_request(struct fw_card *card, struct fw_transaction *t,
-		int tcode, int node_id, int generation, int speed,
-		unsigned long long offset,
-		void *data, size_t length,
+		int tcode, int destination_id, int generation, int speed,
+		unsigned long long offset, void *data, size_t length,
 		fw_transaction_callback_t callback, void *callback_data);
 
+int fw_run_transaction(struct fw_card *card, int tcode, int destination_id,
+		       int generation, int speed, unsigned long long offset,
+		       void *data, size_t length);
+
 int fw_cancel_transaction(struct fw_card *card,
 			  struct fw_transaction *transaction);