sbp2a.c

IEE1394 SBP-2 linux 驱动原码

		if ((i & 0xf) == 0)
			printk("\n   ");
		printk("%02x ", (int)dump[i]);
	}
	printk("\n");

	return;
}
#else
#define sbp2util_packet_dump(w,x,y,z) do {} while (0)
#endif

static DECLARE_WAIT_QUEUE_HEAD(access_wq);

/*
 * Waits for completion of an SBP-2 access request.
 * Returns nonzero if timed out or prematurely interrupted.
 */
static int sbp2util_access_timeout(struct scsi_id_instance_data *scsi_id,
				   int timeout)
{
	long leftover = wait_event_interruptible_timeout(
				access_wq, scsi_id->access_complete, timeout);

	scsi_id->access_complete = 0;
	return leftover <= 0;
}

/* Frees an allocated packet */
static void sbp2_free_packet(struct hpsb_packet *packet)
{
	hpsb_free_tlabel(packet);
	hpsb_free_packet(packet);
}

/* This is much like hpsb_node_write(), except it ignores the response
 * subaction and returns immediately. Can be used from interrupts.
 */
static int sbp2util_node_write_no_wait(struct node_entry *ne, u64 addr,
				       quadlet_t *buffer, size_t length)
{
	struct hpsb_packet *packet;

	packet = hpsb_make_writepacket(ne->host, ne->nodeid,
				       addr, buffer, length);
	if (!packet)
		return -ENOMEM;

	hpsb_set_packet_complete_task(packet,
				      (void (*)(void *))sbp2_free_packet,
				      packet);

	hpsb_node_fill_packet(ne, packet);

	if (hpsb_send_packet(packet) < 0) {
		sbp2_free_packet(packet);
		return -EIO;
	}

	return 0;
}

static void sbp2util_notify_fetch_agent(struct scsi_id_instance_data *scsi_id,
					u64 offset, quadlet_t *data, size_t len)
{
	/*
	 * There is a small window after a bus reset within which the node
	 * entry's generation is current but the reconnect wasn't completed.
	 */
	if (unlikely(atomic_read(&scsi_id->state) == SBP2LU_STATE_IN_RESET))
		return;

	if (hpsb_node_write(scsi_id->ne,
			    scsi_id->sbp2_command_block_agent_addr + offset,
			    data, len))
		SBP2_ERR("sbp2util_notify_fetch_agent failed.");
	/*
	 * Now accept new SCSI commands, unless a bus reset happended during
	 * hpsb_node_write.
	 */
	if (likely(atomic_read(&scsi_id->state) != SBP2LU_STATE_IN_RESET))
		scsi_unblock_requests(scsi_id->scsi_host);
}

static void sbp2util_write_orb_pointer(void *p)
{
	quadlet_t data[2];

	data[0] = ORB_SET_NODE_ID(
			((struct scsi_id_instance_data *)p)->hi->host->node_id);
	data[1] = ((struct scsi_id_instance_data *)p)->last_orb_dma;
	sbp2util_cpu_to_be32_buffer(data, 8);
	sbp2util_notify_fetch_agent(p, SBP2_ORB_POINTER_OFFSET, data, 8);
}

static void sbp2util_write_doorbell(void *p)
{
	sbp2util_notify_fetch_agent(p, SBP2_DOORBELL_OFFSET, NULL, 4);
}

/*
 * This function is called to create a pool of command orbs used for
 * command processing. It is called when a new sbp2 device is detected.
 */
static int sbp2util_create_command_orb_pool(struct scsi_id_instance_data *scsi_id)
{
	struct sbp2scsi_host_info *hi = scsi_id->hi;
	int i;
	unsigned long flags, orbs;
	struct sbp2_command_info *command;

	orbs = serialize_io ? 2 : SBP2_MAX_CMDS;

	spin_lock_irqsave(&scsi_id->sbp2_command_orb_lock, flags);
	for (i = 0; i < orbs; i++) {
		command = kzalloc(sizeof(*command), GFP_ATOMIC);
		if (!command) {
			spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock,
					       flags);
			return -ENOMEM;
		}
		command->command_orb_dma =
		    pci_map_single(hi->host->pdev, &command->command_orb,
				   sizeof(struct sbp2_command_orb),
				   PCI_DMA_TODEVICE);
		SBP2_DMA_ALLOC("single command orb DMA");
		command->sge_dma =
		    pci_map_single(hi->host->pdev,
				   &command->scatter_gather_element,
				   sizeof(command->scatter_gather_element),
				   PCI_DMA_BIDIRECTIONAL);
		SBP2_DMA_ALLOC("scatter_gather_element");
		INIT_LIST_HEAD(&command->list);
		list_add_tail(&command->list, &scsi_id->sbp2_command_orb_completed);
	}
	spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock, flags);
	return 0;
}

/*
 * This function is called to delete a pool of command orbs.
 */
static void sbp2util_remove_command_orb_pool(struct scsi_id_instance_data *scsi_id)
{
	struct hpsb_host *host = scsi_id->hi->host;
	struct list_head *lh, *next;
	struct sbp2_command_info *command;
	unsigned long flags;

	spin_lock_irqsave(&scsi_id->sbp2_command_orb_lock, flags);
	if (!list_empty(&scsi_id->sbp2_command_orb_completed)) {
		list_for_each_safe(lh, next, &scsi_id->sbp2_command_orb_completed) {
			command = list_entry(lh, struct sbp2_command_info, list);

			/* Release our generic DMA's */
			pci_unmap_single(host->pdev, command->command_orb_dma,
					 sizeof(struct sbp2_command_orb),
					 PCI_DMA_TODEVICE);
			SBP2_DMA_FREE("single command orb DMA");
			pci_unmap_single(host->pdev, command->sge_dma,
					 sizeof(command->scatter_gather_element),
					 PCI_DMA_BIDIRECTIONAL);
			SBP2_DMA_FREE("scatter_gather_element");

			kfree(command);
		}
	}
	spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock, flags);
	return;
}

/*
 * This function finds the sbp2_command for a given outstanding command
 * orb.Only looks at the inuse list.
 */
static struct sbp2_command_info *sbp2util_find_command_for_orb(
		struct scsi_id_instance_data *scsi_id, dma_addr_t orb)
{
	struct sbp2_command_info *command;
	unsigned long flags;

	spin_lock_irqsave(&scsi_id->sbp2_command_orb_lock, flags);
	if (!list_empty(&scsi_id->sbp2_command_orb_inuse)) {
		list_for_each_entry(command, &scsi_id->sbp2_command_orb_inuse, list) {
			if (command->command_orb_dma == orb) {
				spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock, flags);
				return command;
			}
		}
	}
	spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock, flags);

	SBP2_ORB_DEBUG("could not match command orb %x", (unsigned int)orb);

	return NULL;
}

/*
 * This function finds the sbp2_command for a given outstanding SCpnt.
 * Only looks at the inuse list.
 * Must be called with scsi_id->sbp2_command_orb_lock held.
 */
static struct sbp2_command_info *sbp2util_find_command_for_SCpnt(
		struct scsi_id_instance_data *scsi_id, void *SCpnt)
{
	struct sbp2_command_info *command;

	if (!list_empty(&scsi_id->sbp2_command_orb_inuse))
		list_for_each_entry(command, &scsi_id->sbp2_command_orb_inuse, list)
			if (command->Current_SCpnt == SCpnt)
				return command;
	return NULL;
}

/*
 * This function allocates a command orb used to send a scsi command.
 */
static struct sbp2_command_info *sbp2util_allocate_command_orb(
		struct scsi_id_instance_data *scsi_id,
		struct scsi_cmnd *Current_SCpnt,
		void (*Current_done)(struct scsi_cmnd *))
{
	struct list_head *lh;
	struct sbp2_command_info *command = NULL;
	unsigned long flags;

	spin_lock_irqsave(&scsi_id->sbp2_command_orb_lock, flags);
	if (!list_empty(&scsi_id->sbp2_command_orb_completed)) {
		lh = scsi_id->sbp2_command_orb_completed.next;
		list_del(lh);
		command = list_entry(lh, struct sbp2_command_info, list);
		command->Current_done = Current_done;
		command->Current_SCpnt = Current_SCpnt;
		list_add_tail(&command->list, &scsi_id->sbp2_command_orb_inuse);
	} else {
		SBP2_ERR("%s: no orbs available", __FUNCTION__);
	}
	spin_unlock_irqrestore(&scsi_id->sbp2_command_orb_lock, flags);
	return command;
}

/* Free our DMA's */
static void sbp2util_free_command_dma(struct sbp2_command_info *command)
{
	struct scsi_id_instance_data *scsi_id =
		(struct scsi_id_instance_data *)command->Current_SCpnt->device->host->hostdata[0];
	struct hpsb_host *host;

	if (!scsi_id) {
		SBP2_ERR("%s: scsi_id == NULL", __FUNCTION__);
		return;
	}

	host = scsi_id->ud->ne->host;

	if (command->cmd_dma) {
		if (command->dma_type == CMD_DMA_SINGLE) {
			pci_unmap_single(host->pdev, command->cmd_dma,
					 command->dma_size, command->dma_dir);
			SBP2_DMA_FREE("single bulk");
		} else if (command->dma_type == CMD_DMA_PAGE) {
			pci_unmap_page(host->pdev, command->cmd_dma,
				       command->dma_size, command->dma_dir);
			SBP2_DMA_FREE("single page");
		} /* XXX: Check for CMD_DMA_NONE bug */
		command->dma_type = CMD_DMA_NONE;
		command->cmd_dma = 0;
	}

	if (command->sge_buffer) {
		pci_unmap_sg(host->pdev, command->sge_buffer,
			     command->dma_size, command->dma_dir);
		SBP2_DMA_FREE("scatter list");
		command->sge_buffer = NULL;
	}
}

/*
 * This function moves a command to the completed orb list.
 * Must be called with scsi_id->sbp2_command_orb_lock held.
 */
static void sbp2util_mark_command_completed(
		struct scsi_id_instance_data *scsi_id,
		struct sbp2_command_info *command)
{
	list_del(&command->list);
	sbp2util_free_command_dma(command);
	list_add_tail(&command->list, &scsi_id->sbp2_command_orb_completed);
}

/*
 * Is scsi_id valid? Is the 1394 node still present?
 */
static inline int sbp2util_node_is_available(struct scsi_id_instance_data *scsi_id)
{
	return scsi_id && scsi_id->ne && !scsi_id->ne->in_limbo;
}

/*********************************************
 * IEEE-1394 core driver stack related section
 *********************************************/
static struct scsi_id_instance_data *sbp2_alloc_device(struct unit_directory *ud);

static int sbp2_probe(struct device *dev)
{
	struct unit_directory *ud;
	struct scsi_id_instance_data *scsi_id;

	SBP2_DEBUG_ENTER();

	ud = container_of(dev, struct unit_directory, device);

	/* Don't probe UD's that have the LUN flag. We'll probe the LUN(s)
	 * instead. */
	if (ud->flags & UNIT_DIRECTORY_HAS_LUN_DIRECTORY)
		return -ENODEV;

	scsi_id = sbp2_alloc_device(ud);

	if (!scsi_id)
		return -ENOMEM;

	sbp2_parse_unit_directory(scsi_id, ud);

	return sbp2_start_device(scsi_id);
}

static int sbp2_remove(struct device *dev)
{
	struct unit_directory *ud;
	struct scsi_id_instance_data *scsi_id;
	struct scsi_device *sdev;

	SBP2_DEBUG_ENTER();

	ud = container_of(dev, struct unit_directory, device);
	scsi_id = ud->device.driver_data;
	if (!scsi_id)
		return 0;

	if (scsi_id->scsi_host) {
		/* Get rid of enqueued commands if there is no chance to
		 * send them. */
		if (!sbp2util_node_is_available(scsi_id))
			sbp2scsi_complete_all_commands(scsi_id, DID_NO_CONNECT);
		/* scsi_remove_device() will trigger shutdown functions of SCSI
		 * highlevel drivers which would deadlock if blocked. */
		atomic_set(&scsi_id->state, SBP2LU_STATE_IN_SHUTDOWN);
		scsi_unblock_requests(scsi_id->scsi_host);
	}
	sdev = scsi_id->sdev;
	if (sdev) {
		scsi_id->sdev = NULL;
		scsi_remove_device(sdev);
	}

	sbp2_logout_device(scsi_id);
	sbp2_remove_device(scsi_id);

	return 0;
}

static int sbp2_update(struct unit_directory *ud)
{
	struct scsi_id_instance_data *scsi_id = ud->device.driver_data;

	SBP2_DEBUG_ENTER();

	if (sbp2_reconnect_device(scsi_id)) {

		/*
		 * Ok, reconnect has failed. Perhaps we didn't
		 * reconnect fast enough. Try doing a regular login, but
		 * first do a logout just in case of any weirdness.
		 */
		sbp2_logout_device(scsi_id);

		if (sbp2_login_device(scsi_id)) {
			/* Login failed too, just fail, and the backend
			 * will call our sbp2_remove for us */
			SBP2_ERR("Failed to reconnect to sbp2 device!");
			return -EBUSY;
		}
	}

	/* Set max retries to something large on the device. */
	sbp2_set_busy_timeout(scsi_id);

	/* Do a SBP-2 fetch agent reset. */
	sbp2_agent_reset(scsi_id, 1);

	/* Get the max speed and packet size that we can use. */
	sbp2_max_speed_and_size(scsi_id);

	/* Complete any pending commands with busy (so they get
	 * retried) and remove them from our queue
	 */
	sbp2scsi_complete_all_commands(scsi_id, DID_BUS_BUSY);

	/* Accept new commands unless there was another bus reset in the
	 * meantime. */
	if (hpsb_node_entry_valid(scsi_id->ne)) {
		atomic_set(&scsi_id->state, SBP2LU_STATE_RUNNING);
		scsi_unblock_requests(scsi_id->scsi_host);
	}
	return 0;
}

/* This functions is called by the sbp2_probe, for each new device. We now
 * allocate one scsi host for each scsi_id (unit directory). */
static struct scsi_id_instance_data *sbp2_alloc_device(struct unit_directory *ud)