Commit 7dc12e84 authored by Takashi Sakamoto's avatar Takashi Sakamoto
Browse files

firewire: core: code refactoring to evaluate transaction result to CSR_BUS_MANAGER_ID 

The call of bm_work should be done after acquiring spin lock of fw_card.
For asynchronous transaction, the lock should be released temporarily
due to event waiting.

A commit 27310d56 ("firewire: core: use guard macro to maintain
properties of fw_card") applied scoped_guard() to the bm_work function,
however it looks hard to follow to the control flow.

This commit refactors the spin lock acquisition after the transaction.

Link: https://lore.kernel.org/r/20250908012108.514698-8-o-takashi@sakamocchi.jp


Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
parent b70a5f33

drivers/firewire/core-card.c

+16 −14
Original line number Diff line number Diff line
@@ -291,7 +291,7 @@ static void bm_work(struct work_struct *work) 
	struct fw_card *card __free(card_unref) = from_work(card, work, bm_work.work);

	struct fw_device *root_device, *irm_device;

	struct fw_node *root_node __free(node_unref) = NULL;

	int root_id, new_root_id, irm_id, bm_id, local_id;

	int root_id, new_root_id, irm_id, local_id;

	int gap_count, generation, grace;

	bool do_reset = false;

	bool root_device_is_running;
@@ -376,20 +376,23 @@ static void bm_work(struct work_struct *work) 
		if (rcode == RCODE_GENERATION)

			return;



		bm_id = be32_to_cpu(data[0]);

		spin_lock_irq(&card->lock);



		scoped_guard(spinlock_irq, &card->lock) {

			if (rcode == RCODE_COMPLETE && generation == card->generation)

				card->bm_node_id =

				    bm_id == 0x3f ? local_id : 0xffc0 | bm_id;

		}

		if (rcode == RCODE_COMPLETE) {

			int bm_id = be32_to_cpu(data[0]);



			if (generation == card->generation)

				card->bm_node_id = bm_id == 0x3f ? local_id : 0xffc0 | bm_id;



			if (bm_id != 0x3f) {

				spin_unlock_irq(&card->lock);



		if (rcode == RCODE_COMPLETE && bm_id != 0x3f) {

			/* Somebody else is BM.  Only act as IRM. */

				// Somebody else is BM.  Only act as IRM.

				if (local_id == irm_id)

					allocate_broadcast_channel(card, generation);

				return;

			}

		}



		if (rcode == RCODE_SEND_ERROR) {

			/*
@@ -397,12 +400,11 @@ static void bm_work(struct work_struct *work) 
			 * some local problem.  Let's try again later and hope

			 * that the problem has gone away by then.

			 */

			spin_unlock_irq(&card->lock);

			fw_schedule_bm_work(card, DIV_ROUND_UP(HZ, 8));

			return;

		}



		spin_lock_irq(&card->lock);



		if (rcode != RCODE_COMPLETE && !keep_this_irm) {

			/*

			 * The lock request failed, maybe the IRM