i2o_core.c

内核linux2.4.20,可跟rtlinux3.2打补丁 组成实时linux系统,编译内核

	/*
	 * Clear event registration as this can cause weird behavior
	 */
	if(c->status_block->iop_state == ADAPTER_STATE_OPERATIONAL)
		i2o_event_register(c, core_context, 0, 0, 0);

	down(&i2o_configuration_lock);
	if((users=atomic_read(&c->users)))
	{
		dprintk(KERN_INFO "I2O: %d users for controller %s\n", users,
			c->name);
		up(&i2o_configuration_lock);
		return -EBUSY;
	}
	while(c->devices)
	{
		if(__i2o_delete_device(c->devices)<0)
		{
			/* Shouldnt happen */
			c->bus_disable(c);
			up(&i2o_configuration_lock);
			return -EBUSY;
		}
	}

	/*
	 * If this is shutdown time, the thread's already been killed
	 */
	if(c->lct_running) {
		stat = kill_proc(c->lct_pid, SIGTERM, 1);
		if(!stat) {
			int count = 10 * 100;
			while(c->lct_running && --count) {
				current->state = TASK_INTERRUPTIBLE;
				schedule_timeout(1);
			}
		
			if(!count)
				printk(KERN_ERR 
					"%s: LCT thread still running!\n", 
					c->name);
		}
	}

	p=&i2o_controller_chain;

	while(*p)
	{
		if(*p==c)
		{
 			/* Ask the IOP to switch to RESET state */
			i2o_reset_controller(c);

			/* Release IRQ */
			c->destructor(c);

			*p=c->next;
			up(&i2o_configuration_lock);

			if(c->page_frame)
			{
				pci_unmap_single(c->pdev, c->page_frame_map, MSG_POOL_SIZE, PCI_DMA_FROMDEVICE);
				kfree(c->page_frame);
			}
			if(c->hrt)
				kfree(c->hrt);
			if(c->lct)
				kfree(c->lct);
			if(c->status_block)
				kfree(c->status_block);
			if(c->dlct)
				kfree(c->dlct);

			i2o_controllers[c->unit]=NULL;
			memcpy(name, c->name, strlen(c->name)+1);
			kfree(c);
			dprintk(KERN_INFO "%s: Deleted from controller chain.\n", name);
			
			i2o_num_controllers--;
			return 0;
		}
		p=&((*p)->next);
	}
	up(&i2o_configuration_lock);
	printk(KERN_ERR "i2o_delete_controller: bad pointer!\n");
	return -ENOENT;
}

/**
 *	i2o_unlock_controller	-	unlock a controller
 *	@c: controller to unlock
 *
 *	Take a lock on an i2o controller. This prevents it being deleted.
 *	i2o controllers are not refcounted so a deletion of an in use device
 *	will fail, not take affect on the last dereference.
 */
 
void i2o_unlock_controller(struct i2o_controller *c)
{
	atomic_dec(&c->users);
}

/**
 *	i2o_find_controller - return a locked controller
 *	@n: controller number
 *
 *	Returns a pointer to the controller object. The controller is locked
 *	on return. NULL is returned if the controller is not found.
 */
 
struct i2o_controller *i2o_find_controller(int n)
{
	struct i2o_controller *c;
	
	if(n<0 || n>=MAX_I2O_CONTROLLERS)
		return NULL;
	
	down(&i2o_configuration_lock);
	c=i2o_controllers[n];
	if(c!=NULL)
		atomic_inc(&c->users);
	up(&i2o_configuration_lock);
	return c;
}

/**
 *	i2o_issue_claim	- claim or release a device
 *	@cmd: command
 *	@c: controller to claim for
 *	@tid: i2o task id
 *	@type: type of claim
 *
 *	Issue I2O UTIL_CLAIM and UTIL_RELEASE messages. The message to be sent
 *	is set by cmd. The tid is the task id of the object to claim and the
 *	type is the claim type (see the i2o standard)
 *
 *	Zero is returned on success.
 */
 
static int i2o_issue_claim(u32 cmd, struct i2o_controller *c, int tid, u32 type)
{
	u32 msg[5];

	msg[0] = FIVE_WORD_MSG_SIZE | SGL_OFFSET_0;
	msg[1] = cmd << 24 | HOST_TID<<12 | tid;
	msg[3] = 0;
	msg[4] = type;
	
	return i2o_post_wait(c, msg, sizeof(msg), 60);
}

/*
 * 	i2o_claim_device - claim a device for use by an OSM
 *	@d: device to claim
 *	@h: handler for this device
 *
 *	Do the leg work to assign a device to a given OSM on Linux. The
 *	kernel updates the internal handler data for the device and then
 *	performs an I2O claim for the device, attempting to claim the
 *	device as primary. If the attempt fails a negative errno code
 *	is returned. On success zero is returned.
 */
 
int i2o_claim_device(struct i2o_device *d, struct i2o_handler *h)
{
	down(&i2o_configuration_lock);
	if (d->owner) {
		printk(KERN_INFO "Device claim called, but dev already owned by %s!",
		       h->name);
		up(&i2o_configuration_lock);
		return -EBUSY;
	}
	d->owner=h;

	if(i2o_issue_claim(I2O_CMD_UTIL_CLAIM ,d->controller,d->lct_data.tid, 
			   I2O_CLAIM_PRIMARY))
	{
		d->owner = NULL;
		return -EBUSY;
	}
	up(&i2o_configuration_lock);
	return 0;
}

/**
 *	i2o_release_device - release a device that the OSM is using
 *	@d: device to claim
 *	@h: handler for this device
 *
 *	Drop a claim by an OSM on a given I2O device. The handler is cleared
 *	and 0 is returned on success.
 *
 *	AC - some devices seem to want to refuse an unclaim until they have
 *	finished internal processing. It makes sense since you don't want a
 *	new device to go reconfiguring the entire system until you are done.
 *	Thus we are prepared to wait briefly.
 */

int i2o_release_device(struct i2o_device *d, struct i2o_handler *h)
{
	int err = 0;
	int tries;

	down(&i2o_configuration_lock);
	if (d->owner != h) {
		printk(KERN_INFO "Claim release called, but not owned by %s!\n",
		       h->name);
		up(&i2o_configuration_lock);
		return -ENOENT;
	}	

	for(tries=0;tries<10;tries++)
	{
		d->owner = NULL;

		/*
		 *	If the controller takes a nonblocking approach to
		 *	releases we have to sleep/poll for a few times.
		 */
		 
		if((err=i2o_issue_claim(I2O_CMD_UTIL_RELEASE, d->controller, d->lct_data.tid, I2O_CLAIM_PRIMARY)) )
		{
			err = -ENXIO;
			current->state = TASK_UNINTERRUPTIBLE;
			schedule_timeout(HZ);
		}
		else
		{
			err=0;
			break;
		}
	}
	up(&i2o_configuration_lock);
	return err;
}

/**
 * 	i2o_device_notify_on	-	Enable deletion notifiers
 *	@d: device for notification
 *	@h: handler to install
 *
 *	Called by OSMs to let the core know that they want to be
 *	notified if the given device is deleted from the system.
 */

int i2o_device_notify_on(struct i2o_device *d, struct i2o_handler *h)
{
	int i;

	if(d->num_managers == I2O_MAX_MANAGERS)
		return -ENOSPC;

	for(i = 0; i < I2O_MAX_MANAGERS; i++)
	{
		if(!d->managers[i])
		{
			d->managers[i] = h;
			break;
		}
	}
	
	d->num_managers++;
	
	return 0;
}

/**
 * 	i2o_device_notify_off	-	Remove deletion notifiers
 *	@d: device for notification
 *	@h: handler to remove
 *
 * Called by OSMs to let the core know that they no longer
 * are interested in the fate of the given device.
 */
int i2o_device_notify_off(struct i2o_device *d, struct i2o_handler *h)
{
	int i;

	for(i=0; i < I2O_MAX_MANAGERS; i++)
	{
		if(d->managers[i] == h)
		{
			d->managers[i] = NULL;
			d->num_managers--;
			return 0;
		}
	}

	return -ENOENT;
}

/**
 *	i2o_event_register	-	register interest in an event
 * 	@c: Controller to register interest with
 *	@tid: I2O task id
 *	@init_context: initiator context to use with this notifier
 *	@tr_context: transaction context to use with this notifier
 *	@evt_mask: mask of events
 *
 *	Create and posts an event registration message to the task. No reply
 *	is waited for, or expected. Errors in posting will be reported.
 */
 
int i2o_event_register(struct i2o_controller *c, u32 tid, 
		u32 init_context, u32 tr_context, u32 evt_mask)
{
	u32 msg[5];	// Not performance critical, so we just 
			// i2o_post_this it instead of building it
			// in IOP memory
	
	msg[0] = FIVE_WORD_MSG_SIZE|SGL_OFFSET_0;
	msg[1] = I2O_CMD_UTIL_EVT_REGISTER<<24 | HOST_TID<<12 | tid;
	msg[2] = init_context;
	msg[3] = tr_context;
	msg[4] = evt_mask;

	return i2o_post_this(c, msg, sizeof(msg));
}

/*
 * 	i2o_event_ack	-	acknowledge an event
 *	@c: controller 
 *	@msg: pointer to the UTIL_EVENT_REGISTER reply we received
 *
 *	We just take a pointer to the original UTIL_EVENT_REGISTER reply
 *	message and change the function code since that's what spec
 *	describes an EventAck message looking like.
 */
 
int i2o_event_ack(struct i2o_controller *c, u32 *msg)
{
	struct i2o_message *m = (struct i2o_message *)msg;

	m->function = I2O_CMD_UTIL_EVT_ACK;

	return i2o_post_wait(c, msg, m->size * 4, 2);
}

/*
 * Core event handler.  Runs as a separate thread and is woken
 * up whenever there is an Executive class event.
 */
static int i2o_core_evt(void *reply_data)
{
	struct reply_info *reply = (struct reply_info *) reply_data;
	u32 *msg = reply->msg;
	struct i2o_controller *c = NULL;
	unsigned long flags;

	lock_kernel();
	daemonize();
	unlock_kernel();

	strcpy(current->comm, "i2oevtd");
	evt_running = 1;

	while(1)
	{
		if(down_interruptible(&evt_sem))
		{
			dprintk(KERN_INFO "I2O event thread dead\n");
			printk("exiting...");
			evt_running = 0;
			complete_and_exit(&evt_dead, 0);
		}

		/* 
		 * Copy the data out of the queue so that we don't have to lock
		 * around the whole function and just around the qlen update
		 */
		spin_lock_irqsave(&i2o_evt_lock, flags);
		memcpy(reply, &events[evt_out], sizeof(struct reply_info));
		MODINC(evt_out, I2O_EVT_Q_LEN);
		evt_q_len--;
		spin_unlock_irqrestore(&i2o_evt_lock, flags);
	
		c = reply->iop;
	 	dprintk(KERN_INFO "I2O IRTOS EVENT: iop%d, event %#10x\n", c->unit, msg[4]);

		/* 
		 * We do not attempt to delete/quiesce/etc. the controller if
		 * some sort of error indidication occurs.  We may want to do
		 * so in the future, but for now we just let the user deal with 
		 * it.  One reason for this is that what to do with an error
		 * or when to send what 鎟ror is not really agreed on, so
		 * we get errors that may not be fatal but just look like they
		 * are...so let the user deal with it.
		 */
		switch(msg[4])
		{
			case I2O_EVT_IND_EXEC_RESOURCE_LIMITS:
				printk(KERN_ERR "%s: Out of resources\n", c->name);
				break;

			case I2O_EVT_IND_EXEC_POWER_FAIL:
				printk(KERN_ERR "%s: Power failure\n", c->name);
				break;

			case I2O_EVT_IND_EXEC_HW_FAIL:
			{
				char *fail[] = 
					{ 
						"Unknown Error",
						"Power Lost",
						"Code Violation",
						"Parity Error",
						"Code Execution Exception",
						"Watchdog Timer Expired" 
					};

				if(msg[5] <= 6)
					printk(KERN_ERR "%s: Hardware Failure: %s\n", 
						c->name, fail[msg[5]]);
				else
					printk(KERN_ERR "%s: Unknown Hardware Failure\n", c->name);

				break;
			}

			/*
		 	 * New device created
		 	 * - Create a new i2o_device entry
		 	 * - Inform all interested drivers about this device's existence
		 	 */
			case I2O_EVT_IND_EXEC_NEW_LCT_ENTRY:
			{
				struct i2o_device *d = (struct i2o_device *)
					kmalloc(sizeof(struct i2o_device), GFP_KERNEL);
				int i;

				if (d == NULL) {
					printk(KERN_EMERG "i2oevtd: out of memory\n");
					break;
				}
				memcpy(&d->lct_data, &msg[5], sizeof(i2o_lct_entry));
	
				d->next = NULL;
				d->controller = c;
				d->flags = 0;
	
				i2o_report_controller_unit(c, d);
				i2o_install_device(c,d);
	
				for(i = 0; i < MAX_I2O_MODULES; i++)
				{
					if(i2o_handlers[i] && 
						i2o_handlers[i]->new_dev_notify &&
						(i2o_handlers[i]->class&d->lct_data.class_id))
						{
						spin_lock(&i2o_dev_lock);
						i2o_handlers[i]->new_dev_notify(c,d);
						spin_unlock(&i2o_dev_lock);
						}
				}
			
				break;
			}
	
			/*
 		 	 * LCT entry for a device has been modified, so update it
		 	 * internally.
		 	 */
			case I2O_EVT_IND_EXEC_MODIFIED_LCT:
			{
				struct i2o_device *d;
				i2o_lct_entry *new_lct = (i2o_lct_entry *)&msg[5];

				for(d = c->devices; d; d = d->next)
				{
					if(d->lct_data.tid == new_lct->tid)
					{
						memcpy(&d->lct_data, new_lct, sizeof(i2o_lct_entry));
						break;
					}
				}
				break;
			}
	
			case I2O_EVT_IND_CONFIGURATION_FLAG:
				printk(KERN_WARNING "%s requires user configuration\n", c->name);
				break;
	
			case I2O_EVT_IND_GENERAL_WARNING:
				printk(KERN_WARNING "%s: Warning notification received!"
					"Check configuration for errors!\n", c->name);
				break;
				
			case I2O_EVT_IND_EVT_MASK_MODIFIED:
				/* Well I guess that was us hey .. */
				break;
					
			default:
				printk(KERN_WARNING "%s: No handler for event (0x%08x)\n", c->name, msg[4]);
				break;
		}
	}

	return 0;
}

/*
 * Dynamic LCT update.  This compares the LCT with the currently
 * installed devices to check for device deletions..this needed b/c there
 * is no DELETED_LCT_ENTRY EventIndicator for the Executive class so
 * we can't just have the event handler do this...annoying
 *
 * This is a hole in the spec that will hopefully be fixed someday.
 */
static int i2o_dyn_lct(void *foo)
{
	struct i2o_controller *c = (struct i2o_controller *)foo;
	struct i2o_device *d = NULL;
	struct i2o_device *d1 = NULL;
	int i = 0;
	int found = 0;
	int entries;
	void *tmp;
	char name[16];

	lock_kernel();
	daemonize();
	unlock_kernel();

	sprintf(name, "iop%d_lctd", c->unit);
	strcpy(current->comm, name);	
	
	c->lct_running = 1;

	while(1)
	{
		down_interruptible(&c->lct_sem);
		if(signal_pending(current))
		{
			dprintk(KERN_ERR "%s: LCT thread dead\n", c->name);
			c->lct_running = 0;
			return 0;
		}

		entries = c->dlct->table_size;
		entries -= 3;
		entries /= 9;

		dprintk(KERN_INFO "%s: Dynamic LCT Update\n",c->name);
		dprintk(KERN_INFO "%s: Dynamic LCT contains %d entries\n", c->name, entries);

		if(!entries)
		{
			printk(KERN_INFO "%s: Empty LCT???\n", c->name);