Merge tag 'firewire-updates-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394

Pull firewire updates from Takashi Sakamoto:
 "This update includes the following changes:

   - Removal of the deprecated debug parameter from firewire-ohci module

   - Replacement of the module-local workqueue in 1394 OHCI PCI driver
     with a companion IRQ thread

   - Refactoring of bus management code

   - Additional minor code cleanup

  The existing tracepoints serve as an alternative to the removed debug
  parameter. The use of IRQ thread is experimental, as it handles 1394
  OHCI SelfIDComplete event only. It may be replaced in the future
  releases with another approach; e.g. by providing workqueue from core
  functionality"

* tag 'firewire-updates-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394: (43 commits)
  firewire: core: fix undefined reference error in ARM EABI
  Revert "firewire: core: disable bus management work temporarily during updating topology"
  Revert "firewire: core: shrink critical section of fw_card spinlock in bm_work"
  firewire: core: suppress overflow warning when computing jiffies from isochronous cycle
  firewire: core: minor code refactoring to delete useless local variable
  firewire: core; eliminate pick_me goto label
  firewire: core: code refactoring to split contention procedure for bus manager
  firewire: core: code refactoring for the case of generation mismatch
  firewire: core: use switch statement to evaluate transaction result to CSR_BUS_MANAGER_ID
  firewire: core: remove useless generation check
  firewire: core: use struct_size and flex_array_size in ioctl_add_descriptor
  firewire: core: shrink critical section of fw_card spinlock in bm_work
  firewire: core: disable bus management work temporarily during updating topology
  firewire: core: schedule bm_work item outside of spin lock
  firewire: core: annotate fw_destroy_nodes with must-hold-lock
  firewire: core: use spin lock specific to timer for split transaction
  firewire: core: use spin lock specific to transaction
  firewire: core: use spin lock specific to topology map
  firewire: core: maintain phy packet receivers locally in cdev layer
  firewire: core: use scoped_guard() to manage critical section to update topology
  ...

Author: torvalds

drivers/firewire/core-card.c

@@ -47,6 +47,9 @@
 #define FW_CDEV_VERSION_AUTO_FLUSH_ISO_OVERFLOW	5
 #define FW_CDEV_VERSION_EVENT_ASYNC_TSTAMP	6
 
+static DEFINE_SPINLOCK(phy_receiver_list_lock);
+static LIST_HEAD(phy_receiver_list);
+
 struct client {
 	u32 version;
 	struct fw_device *device;
@@ -937,11 +940,12 @@ static int ioctl_add_descriptor(struct client *client, union ioctl_arg *arg)
 	if (a->length > 256)
 		return -EINVAL;
 
-	r = kmalloc(sizeof(*r) + a->length * 4, GFP_KERNEL);
+	r = kmalloc(struct_size(r, data, a->length), GFP_KERNEL);
 	if (r == NULL)
 		return -ENOMEM;
 
-	if (copy_from_user(r->data, u64_to_uptr(a->data), a->length * 4)) {
+	if (copy_from_user(r->data, u64_to_uptr(a->data),
+			   flex_array_size(r, data, a->length))) {
 		ret = -EFAULT;
 		goto failed;
 	}
@@ -1324,8 +1328,8 @@ static void iso_resource_work(struct work_struct *work)
 		todo = r->todo;
 		// Allow 1000ms grace period for other reallocations.
 		if (todo == ISO_RES_ALLOC &&
-		    time_before64(get_jiffies_64(), client->device->card->reset_jiffies + HZ)) {
-			schedule_iso_resource(r, DIV_ROUND_UP(HZ, 3));
+		    time_is_after_jiffies64(client->device->card->reset_jiffies + secs_to_jiffies(1))) {
+			schedule_iso_resource(r, msecs_to_jiffies(333));
 			skip = true;
 		} else {
 			// We could be called twice within the same generation.
@@ -1669,15 +1673,16 @@ static int ioctl_send_phy_packet(struct client *client, union ioctl_arg *arg)
 static int ioctl_receive_phy_packets(struct client *client, union ioctl_arg *arg)
 {
 	struct fw_cdev_receive_phy_packets *a = &arg->receive_phy_packets;
-	struct fw_card *card = client->device->card;
 
 	/* Access policy: Allow this ioctl only on local nodes' device files. */
 	if (!client->device->is_local)
 		return -ENOSYS;
 
-	guard(spinlock_irq)(&card->lock);
+	// NOTE: This can be without irq when we can guarantee that __fw_send_request() for local
+	// destination never runs in any type of IRQ context.
+	scoped_guard(spinlock_irq, &phy_receiver_list_lock)
+		list_move_tail(&client->phy_receiver_link, &phy_receiver_list);
 
-	list_move_tail(&client->phy_receiver_link, &card->phy_receiver_list);
 	client->phy_receiver_closure = a->closure;
 
 	return 0;
@@ -1687,10 +1692,17 @@ void fw_cdev_handle_phy_packet(struct fw_card *card, struct fw_packet *p)
 {
 	struct client *client;
 
-	guard(spinlock_irqsave)(&card->lock);
+	// NOTE: This can be without irqsave when we can guarantee that __fw_send_request() for local
+	// destination never runs in any type of IRQ context.
+	guard(spinlock_irqsave)(&phy_receiver_list_lock);
+
+	list_for_each_entry(client, &phy_receiver_list, phy_receiver_link) {
+		struct inbound_phy_packet_event *e;
+
+		if (client->device->card != card)
+			continue;
 
-	list_for_each_entry(client, &card->phy_receiver_list, phy_receiver_link) {
-		struct inbound_phy_packet_event *e = kmalloc(sizeof(*e) + 8, GFP_ATOMIC);
+		e = kmalloc(sizeof(*e) + 8, GFP_ATOMIC);
 		if (e == NULL)
 			break;
 
@@ -1857,7 +1869,9 @@ static int fw_device_op_release(struct inode *inode, struct file *file)
 	struct client_resource *resource;
 	unsigned long index;
 
-	scoped_guard(spinlock_irq, &client->device->card->lock)
+	// NOTE: This can be without irq when we can guarantee that __fw_send_request() for local
+	// destination never runs in any type of IRQ context.
+	scoped_guard(spinlock_irq, &phy_receiver_list_lock)
 		list_del(&client->phy_receiver_link);
 
 	scoped_guard(mutex, &client->device->client_list_mutex)

drivers/firewire/core-cdev.c

@@ -847,16 +847,15 @@ static void fw_schedule_device_work(struct fw_device *device,
  */
 
 #define MAX_RETRIES	10
-#define RETRY_DELAY	(3 * HZ)
-#define INITIAL_DELAY	(HZ / 2)
-#define SHUTDOWN_DELAY	(2 * HZ)
+#define RETRY_DELAY	secs_to_jiffies(3)
+#define INITIAL_DELAY	msecs_to_jiffies(500)
+#define SHUTDOWN_DELAY	secs_to_jiffies(2)
 
 static void fw_device_shutdown(struct work_struct *work)
 {
 	struct fw_device *device = from_work(device, work, work.work);
 
-	if (time_before64(get_jiffies_64(),
-			  device->card->reset_jiffies + SHUTDOWN_DELAY)
+	if (time_is_after_jiffies64(device->card->reset_jiffies + SHUTDOWN_DELAY)
 	    && !list_empty(&device->card->link)) {
 		fw_schedule_device_work(device, SHUTDOWN_DELAY);
 		return;
@@ -887,7 +886,7 @@ static void fw_device_release(struct device *dev)
 	 * bus manager work looks at this node.
 	 */
 	scoped_guard(spinlock_irqsave, &card->lock)
-		device->node->data = NULL;
+		fw_node_set_device(device->node, NULL);
 
 	fw_node_put(device->node);
 	kfree(device->config_rom);
@@ -1007,7 +1006,7 @@ static void fw_device_init(struct work_struct *work)
 	int ret;
 
 	/*
-	 * All failure paths here set node->data to NULL, so that we
+	 * All failure paths here call fw_node_set_device(node, NULL), so that we
 	 * don't try to do device_for_each_child() on a kfree()'d
 	 * device.
 	 */
@@ -1051,9 +1050,9 @@ static void fw_device_init(struct work_struct *work)
 				struct fw_node *obsolete_node = reused->node;
 
 				device->node = obsolete_node;
-				device->node->data = device;
+				fw_node_set_device(device->node, device);
 				reused->node = current_node;
-				reused->node->data = reused;
+				fw_node_set_device(reused->node, reused);
 
 				reused->max_speed = device->max_speed;
 				reused->node_id = current_node->node_id;
@@ -1292,7 +1291,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 		 * FW_NODE_UPDATED callbacks can update the node_id
 		 * and generation for the device.
 		 */
-		node->data = device;
+		fw_node_set_device(node, device);
 
 		/*
 		 * Many devices are slow to respond after bus resets,
@@ -1307,7 +1306,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 
 	case FW_NODE_INITIATED_RESET:
 	case FW_NODE_LINK_ON:
-		device = node->data;
+		device = fw_node_get_device(node);
 		if (device == NULL)
 			goto create;
 
@@ -1324,7 +1323,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 		break;
 
 	case FW_NODE_UPDATED:
-		device = node->data;
+		device = fw_node_get_device(node);
 		if (device == NULL)
 			break;
 
@@ -1339,7 +1338,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 
 	case FW_NODE_DESTROYED:
 	case FW_NODE_LINK_OFF:
-		if (!node->data)
+		if (!fw_node_get_device(node))
 			break;
 
 		/*
@@ -1354,7 +1353,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 		 * the device in shutdown state to have that code fail
 		 * to create the device.
 		 */
-		device = node->data;
+		device = fw_node_get_device(node);
 		if (atomic_xchg(&device->state,
 				FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
 			device->workfn = fw_device_shutdown;

drivers/firewire/core-device.c

@@ -241,7 +241,7 @@ static struct fw_node *build_tree(struct fw_card *card, const u32 *sid, int self
 		// If PHYs report different gap counts, set an invalid count which will force a gap
 		// count reconfiguration and a reset.
 		if (phy_packet_self_id_zero_get_gap_count(self_id_sequence[0]) != gap_count)
-			gap_count = 0;
+			gap_count = GAP_COUNT_MISMATCHED;
 
 		update_hop_count(node);
 
@@ -325,9 +325,11 @@ static void report_found_node(struct fw_card *card,
 	card->bm_retries = 0;
 }
 
-/* Must be called with card->lock held */
 void fw_destroy_nodes(struct fw_card *card)
+__must_hold(&card->lock)
 {
+	lockdep_assert_held(&card->lock);
+
 	card->color++;
 	if (card->local_node != NULL)
 		for_each_fw_node(card, card->local_node, report_lost_node);
@@ -435,20 +437,22 @@ static void update_tree(struct fw_card *card, struct fw_node *root)
 	}
 }
 
-static void update_topology_map(struct fw_card *card,
-				u32 *self_ids, int self_id_count)
+static void update_topology_map(__be32 *buffer, size_t buffer_size, int root_node_id,
+				const u32 *self_ids, int self_id_count)
 {
-	int node_count = (card->root_node->node_id & 0x3f) + 1;
-	__be32 *map = card->topology_map;
+	__be32 *map = buffer;
+	int node_count = (root_node_id & 0x3f) + 1;
+
+	memset(map, 0, buffer_size);
 
 	*map++ = cpu_to_be32((self_id_count + 2) << 16);
-	*map++ = cpu_to_be32(be32_to_cpu(card->topology_map[1]) + 1);
+	*map++ = cpu_to_be32(be32_to_cpu(buffer[1]) + 1);
 	*map++ = cpu_to_be32((node_count << 16) | self_id_count);
 
 	while (self_id_count--)
 		*map++ = cpu_to_be32p(self_ids++);
 
-	fw_compute_block_crc(card->topology_map);
+	fw_compute_block_crc(buffer);
 }
 
 void fw_core_handle_bus_reset(struct fw_card *card, int node_id, int generation,
@@ -458,46 +462,45 @@ void fw_core_handle_bus_reset(struct fw_card *card, int node_id, int generation,
 
 	trace_bus_reset_handle(card->index, generation, node_id, bm_abdicate, self_ids, self_id_count);
 
-	guard(spinlock_irqsave)(&card->lock);
-
-	/*
-	 * If the selfID buffer is not the immediate successor of the
-	 * previously processed one, we cannot reliably compare the
-	 * old and new topologies.
-	 */
-	if (!is_next_generation(generation, card->generation) &&
-	    card->local_node != NULL) {
-		fw_destroy_nodes(card);
-		card->bm_retries = 0;
+	scoped_guard(spinlock, &card->lock) {
+		// If the selfID buffer is not the immediate successor of the
+		// previously processed one, we cannot reliably compare the
+		// old and new topologies.
+		if (!is_next_generation(generation, card->generation) && card->local_node != NULL) {
+			fw_destroy_nodes(card);
+			card->bm_retries = 0;
+		}
+		card->broadcast_channel_allocated = card->broadcast_channel_auto_allocated;
+		card->node_id = node_id;
+		// Update node_id before generation to prevent anybody from using
+		// a stale node_id together with a current generation.
+		smp_wmb();
+		card->generation = generation;
+		card->reset_jiffies = get_jiffies_64();
+		card->bm_node_id  = 0xffff;
+		card->bm_abdicate = bm_abdicate;
+
+		local_node = build_tree(card, self_ids, self_id_count, generation);
+
+		card->color++;
+
+		if (local_node == NULL) {
+			fw_err(card, "topology build failed\n");
+			// FIXME: We need to issue a bus reset in this case.
+		} else if (card->local_node == NULL) {
+			card->local_node = local_node;
+			for_each_fw_node(card, local_node, report_found_node);
+		} else {
+			update_tree(card, local_node);
+		}
 	}
 
-	card->broadcast_channel_allocated = card->broadcast_channel_auto_allocated;
-	card->node_id = node_id;
-	/*
-	 * Update node_id before generation to prevent anybody from using
-	 * a stale node_id together with a current generation.
-	 */
-	smp_wmb();
-	card->generation = generation;
-	card->reset_jiffies = get_jiffies_64();
-	card->bm_node_id  = 0xffff;
-	card->bm_abdicate = bm_abdicate;
 	fw_schedule_bm_work(card, 0);
 
-	local_node = build_tree(card, self_ids, self_id_count, generation);
-
-	update_topology_map(card, self_ids, self_id_count);
-
-	card->color++;
-
-	if (local_node == NULL) {
-		fw_err(card, "topology build failed\n");
-		/* FIXME: We need to issue a bus reset in this case. */
-	} else if (card->local_node == NULL) {
-		card->local_node = local_node;
-		for_each_fw_node(card, local_node, report_found_node);
-	} else {
-		update_tree(card, local_node);
+	// Just used by transaction layer.
+	scoped_guard(spinlock, &card->topology_map.lock) {
+		update_topology_map(card->topology_map.buffer, sizeof(card->topology_map.buffer),
+				    card->root_node->node_id, self_ids, self_id_count);
 	}
 }
 EXPORT_SYMBOL(fw_core_handle_bus_reset);