cmf.c

linux-2.6.15.6

		spin_unlock_irqrestore(cdev->ccwlock, flags);
		return -ENODEV;
	}

	cmb = *(struct cmb*)cdev->private->cmb;
	time = get_clock() - cdev->private->cmb_start_time;
	spin_unlock_irqrestore(cdev->ccwlock, flags);

	memset(data, 0, sizeof(struct cmbdata));

	/* we only know values before device_busy_time */
	data->size = offsetof(struct cmbdata, device_busy_time);

	/* convert to nanoseconds */
	data->elapsed_time = (time * 1000) >> 12;

	/* copy data to new structure */
	data->ssch_rsch_count = cmb.ssch_rsch_count;
	data->sample_count = cmb.sample_count;

	/* time fields are converted to nanoseconds while copying */
	data->device_connect_time = time_to_nsec(cmb.device_connect_time);
	data->function_pending_time = time_to_nsec(cmb.function_pending_time);
	data->device_disconnect_time = time_to_nsec(cmb.device_disconnect_time);
	data->control_unit_queuing_time
		= time_to_nsec(cmb.control_unit_queuing_time);
	data->device_active_only_time
		= time_to_nsec(cmb.device_active_only_time);

	return 0;
}

static void
reset_cmb(struct ccw_device *cdev)
{
	struct cmb *cmb;
	spin_lock_irq(cdev->ccwlock);
	cmb = cdev->private->cmb;
	if (cmb)
		memset (cmb, 0, sizeof (*cmb));
	cdev->private->cmb_start_time = get_clock();
	spin_unlock_irq(cdev->ccwlock);
}

static struct attribute_group cmf_attr_group;

static struct cmb_operations cmbops_basic = {
	.alloc	= alloc_cmb,
	.free	= free_cmb,
	.set	= set_cmb,
	.read	= read_cmb,
	.readall    = readall_cmb,
	.reset	    = reset_cmb,
	.attr_group = &cmf_attr_group,
};

/* ******** extended cmb handling ********/

/**
 * struct cmbe - extended channel measurement block
 *
 * cmb as used by the hardware, may be in any 64 bit physical location,
 * the fields are described in z/Architecture Principles of Operation,
 * third edition, chapter 17.
 */
struct cmbe {
	u32 ssch_rsch_count;
	u32 sample_count;
	u32 device_connect_time;
	u32 function_pending_time;
	u32 device_disconnect_time;
	u32 control_unit_queuing_time;
	u32 device_active_only_time;
	u32 device_busy_time;
	u32 initial_command_response_time;
	u32 reserved[7];
};

/* kmalloc only guarantees 8 byte alignment, but we need cmbe
 * pointers to be naturally aligned. Make sure to allocate
 * enough space for two cmbes */
static inline struct cmbe* cmbe_align(struct cmbe *c)
{
	unsigned long addr;
	addr = ((unsigned long)c + sizeof (struct cmbe) - sizeof(long)) &
				 ~(sizeof (struct cmbe) - sizeof(long));
	return (struct cmbe*)addr;
}

static int
alloc_cmbe (struct ccw_device *cdev)
{
	struct cmbe *cmbe;
	cmbe = kmalloc (sizeof (*cmbe) * 2, GFP_KERNEL);
	if (!cmbe)
		return -ENOMEM;

	spin_lock_irq(cdev->ccwlock);
	if (cdev->private->cmb) {
		kfree(cmbe);
		spin_unlock_irq(cdev->ccwlock);
		return -EBUSY;
	}

	cdev->private->cmb = cmbe;
	spin_unlock_irq(cdev->ccwlock);

	/* activate global measurement if this is the first channel */
	spin_lock(&cmb_area.lock);
	if (list_empty(&cmb_area.list))
		cmf_activate(NULL, 1);
	list_add_tail(&cdev->private->cmb_list, &cmb_area.list);
	spin_unlock(&cmb_area.lock);

	return 0;
}

static void
free_cmbe (struct ccw_device *cdev)
{
	spin_lock_irq(cdev->ccwlock);
	kfree(cdev->private->cmb);
	cdev->private->cmb = NULL;
	spin_unlock_irq(cdev->ccwlock);

	/* deactivate global measurement if this is the last channel */
	spin_lock(&cmb_area.lock);
	list_del_init(&cdev->private->cmb_list);
	if (list_empty(&cmb_area.list))
		cmf_activate(NULL, 0);
	spin_unlock(&cmb_area.lock);
}

static int
set_cmbe(struct ccw_device *cdev, u32 mme)
{
	unsigned long mba;

	if (!cdev->private->cmb)
		return -EINVAL;
	mba = mme ? (unsigned long) cmbe_align(cdev->private->cmb) : 0;

	return set_schib_wait(cdev, mme, 1, mba);
}


u64
read_cmbe (struct ccw_device *cdev, int index)
{
	/* yes, we have to put it on the stack
	 * because the cmb must only be accessed
	 * atomically, e.g. with mvc */
	struct cmbe cmb;
	unsigned long flags;
	u32 val;

	spin_lock_irqsave(cdev->ccwlock, flags);
	if (!cdev->private->cmb) {
		spin_unlock_irqrestore(cdev->ccwlock, flags);
		return 0;
	}

	cmb = *cmbe_align(cdev->private->cmb);
	spin_unlock_irqrestore(cdev->ccwlock, flags);

	switch (index) {
	case cmb_ssch_rsch_count:
		return cmb.ssch_rsch_count;
	case cmb_sample_count:
		return cmb.sample_count;
	case cmb_device_connect_time:
		val = cmb.device_connect_time;
		break;
	case cmb_function_pending_time:
		val = cmb.function_pending_time;
		break;
	case cmb_device_disconnect_time:
		val = cmb.device_disconnect_time;
		break;
	case cmb_control_unit_queuing_time:
		val = cmb.control_unit_queuing_time;
		break;
	case cmb_device_active_only_time:
		val = cmb.device_active_only_time;
		break;
	case cmb_device_busy_time:
		val = cmb.device_busy_time;
		break;
	case cmb_initial_command_response_time:
		val = cmb.initial_command_response_time;
		break;
	default:
		return 0;
	}
	return time_to_avg_nsec(val, cmb.sample_count);
}

static int
readall_cmbe (struct ccw_device *cdev, struct cmbdata *data)
{
	/* yes, we have to put it on the stack
	 * because the cmb must only be accessed
	 * atomically, e.g. with mvc */
	struct cmbe cmb;
	unsigned long flags;
	u64 time;

	spin_lock_irqsave(cdev->ccwlock, flags);
	if (!cdev->private->cmb) {
		spin_unlock_irqrestore(cdev->ccwlock, flags);
		return -ENODEV;
	}

	cmb = *cmbe_align(cdev->private->cmb);
	time = get_clock() - cdev->private->cmb_start_time;
	spin_unlock_irqrestore(cdev->ccwlock, flags);

	memset (data, 0, sizeof(struct cmbdata));

	/* we only know values before device_busy_time */
	data->size = offsetof(struct cmbdata, device_busy_time);

	/* conver to nanoseconds */
	data->elapsed_time = (time * 1000) >> 12;

	/* copy data to new structure */
	data->ssch_rsch_count = cmb.ssch_rsch_count;
	data->sample_count = cmb.sample_count;

	/* time fields are converted to nanoseconds while copying */
	data->device_connect_time = time_to_nsec(cmb.device_connect_time);
	data->function_pending_time = time_to_nsec(cmb.function_pending_time);
	data->device_disconnect_time = time_to_nsec(cmb.device_disconnect_time);
	data->control_unit_queuing_time
		= time_to_nsec(cmb.control_unit_queuing_time);
	data->device_active_only_time
		= time_to_nsec(cmb.device_active_only_time);
	data->device_busy_time = time_to_nsec(cmb.device_busy_time);
	data->initial_command_response_time
		= time_to_nsec(cmb.initial_command_response_time);

	return 0;
}

static void
reset_cmbe(struct ccw_device *cdev)
{
	struct cmbe *cmb;
	spin_lock_irq(cdev->ccwlock);
	cmb = cmbe_align(cdev->private->cmb);
	if (cmb)
		memset (cmb, 0, sizeof (*cmb));
	cdev->private->cmb_start_time = get_clock();
	spin_unlock_irq(cdev->ccwlock);
}

static struct attribute_group cmf_attr_group_ext;

static struct cmb_operations cmbops_extended = {
	.alloc	    = alloc_cmbe,
	.free	    = free_cmbe,
	.set	    = set_cmbe,
	.read	    = read_cmbe,
	.readall    = readall_cmbe,
	.reset	    = reset_cmbe,
	.attr_group = &cmf_attr_group_ext,
};


static ssize_t
cmb_show_attr(struct device *dev, char *buf, enum cmb_index idx)
{
	return sprintf(buf, "%lld\n",
		(unsigned long long) cmf_read(to_ccwdev(dev), idx));
}

static ssize_t
cmb_show_avg_sample_interval(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct ccw_device *cdev;
	long interval;
	unsigned long count;

	cdev = to_ccwdev(dev);
	interval  = get_clock() - cdev->private->cmb_start_time;
	count = cmf_read(cdev, cmb_sample_count);
	if (count)
		interval /= count;
	else
		interval = -1;
	return sprintf(buf, "%ld\n", interval);
}

static ssize_t
cmb_show_avg_utilization(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct cmbdata data;
	u64 utilization;
	unsigned long t, u;
	int ret;

	ret = cmf_readall(to_ccwdev(dev), &data);
	if (ret)
		return ret;

	utilization = data.device_connect_time +
		      data.function_pending_time +
		      data.device_disconnect_time;

	/* shift to avoid long long division */
	while (-1ul < (data.elapsed_time | utilization)) {
		utilization >>= 8;
		data.elapsed_time >>= 8;
	}

	/* calculate value in 0.1 percent units */
	t = (unsigned long) data.elapsed_time / 1000;
	u = (unsigned long) utilization / t;

	return sprintf(buf, "%02ld.%01ld%%\n", u/ 10, u - (u/ 10) * 10);
}

#define cmf_attr(name) \
static ssize_t show_ ## name (struct device * dev, struct device_attribute *attr, char * buf) \
{ return cmb_show_attr((dev), buf, cmb_ ## name); } \
static DEVICE_ATTR(name, 0444, show_ ## name, NULL);

#define cmf_attr_avg(name) \
static ssize_t show_avg_ ## name (struct device * dev, struct device_attribute *attr, char * buf) \
{ return cmb_show_attr((dev), buf, cmb_ ## name); } \
static DEVICE_ATTR(avg_ ## name, 0444, show_avg_ ## name, NULL);

cmf_attr(ssch_rsch_count);
cmf_attr(sample_count);
cmf_attr_avg(device_connect_time);
cmf_attr_avg(function_pending_time);
cmf_attr_avg(device_disconnect_time);
cmf_attr_avg(control_unit_queuing_time);
cmf_attr_avg(device_active_only_time);
cmf_attr_avg(device_busy_time);
cmf_attr_avg(initial_command_response_time);

static DEVICE_ATTR(avg_sample_interval, 0444, cmb_show_avg_sample_interval, NULL);
static DEVICE_ATTR(avg_utilization, 0444, cmb_show_avg_utilization, NULL);

static struct attribute *cmf_attributes[] = {
	&dev_attr_avg_sample_interval.attr,
	&dev_attr_avg_utilization.attr,
	&dev_attr_ssch_rsch_count.attr,
	&dev_attr_sample_count.attr,
	&dev_attr_avg_device_connect_time.attr,
	&dev_attr_avg_function_pending_time.attr,
	&dev_attr_avg_device_disconnect_time.attr,
	&dev_attr_avg_control_unit_queuing_time.attr,
	&dev_attr_avg_device_active_only_time.attr,
	0,
};

static struct attribute_group cmf_attr_group = {
	.name  = "cmf",
	.attrs = cmf_attributes,
};

static struct attribute *cmf_attributes_ext[] = {
	&dev_attr_avg_sample_interval.attr,
	&dev_attr_avg_utilization.attr,
	&dev_attr_ssch_rsch_count.attr,
	&dev_attr_sample_count.attr,
	&dev_attr_avg_device_connect_time.attr,
	&dev_attr_avg_function_pending_time.attr,
	&dev_attr_avg_device_disconnect_time.attr,
	&dev_attr_avg_control_unit_queuing_time.attr,
	&dev_attr_avg_device_active_only_time.attr,
	&dev_attr_avg_device_busy_time.attr,
	&dev_attr_avg_initial_command_response_time.attr,
	0,
};

static struct attribute_group cmf_attr_group_ext = {
	.name  = "cmf",
	.attrs = cmf_attributes_ext,
};

static ssize_t cmb_enable_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "%d\n", to_ccwdev(dev)->private->cmb ? 1 : 0);
}

static ssize_t cmb_enable_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t c)
{
	struct ccw_device *cdev;
	int ret;

	cdev = to_ccwdev(dev);

	switch (buf[0]) {
	case '0':
		ret = disable_cmf(cdev);
		if (ret)
			printk(KERN_INFO "disable_cmf failed (%d)\n", ret);
		break;
	case '1':
		ret = enable_cmf(cdev);
		if (ret && ret != -EBUSY)
			printk(KERN_INFO "enable_cmf failed (%d)\n", ret);
		break;
	}

	return c;
}

DEVICE_ATTR(cmb_enable, 0644, cmb_enable_show, cmb_enable_store);

/* enable_cmf/disable_cmf: module interface for cmf (de)activation */
int
enable_cmf(struct ccw_device *cdev)
{
	int ret;

	ret = cmbops->alloc(cdev);
	cmbops->reset(cdev);
	if (ret)
		return ret;
	ret = cmbops->set(cdev, 2);
	if (ret) {
		cmbops->free(cdev);
		return ret;
	}
	ret = sysfs_create_group(&cdev->dev.kobj, cmbops->attr_group);
	if (!ret)
		return 0;
	cmbops->set(cdev, 0);  //FIXME: this can fail
	cmbops->free(cdev);
	return ret;
}

int
disable_cmf(struct ccw_device *cdev)
{
	int ret;

	ret = cmbops->set(cdev, 0);
	if (ret)
		return ret;
	cmbops->free(cdev);
	sysfs_remove_group(&cdev->dev.kobj, cmbops->attr_group);
	return ret;
}

u64
cmf_read(struct ccw_device *cdev, int index)
{
	return cmbops->read(cdev, index);
}

int
cmf_readall(struct ccw_device *cdev, struct cmbdata *data)
{
	return cmbops->readall(cdev, data);
}

static int __init
init_cmf(void)
{
	char *format_string;
	char *detect_string = "parameter";

	/* We cannot really autoprobe this. If the user did not give a parameter,
	   see if we are running on z990 or up, otherwise fall back to basic mode. */

	if (format == CMF_AUTODETECT) {
		if (!css_characteristics_avail ||
		    !css_general_characteristics.ext_mb) {
			format = CMF_BASIC;
		} else {
			format = CMF_EXTENDED;
		}
		detect_string = "autodetected";
	} else {
		detect_string = "parameter";
	}

	switch (format) {
	case CMF_BASIC:
		format_string = "basic";
		cmbops = &cmbops_basic;
		if (cmb_area.num_channels > 4096 || cmb_area.num_channels < 1) {
			printk(KERN_ERR "Basic channel measurement facility"
					" can only use 1 to 4096 devices\n"
			       KERN_ERR "when the cmf driver is built"
					" as a loadable module\n");
			return 1;
		}
		break;
	case CMF_EXTENDED:
 		format_string = "extended";
		cmbops = &cmbops_extended;
		break;
	default:
		printk(KERN_ERR "Invalid format %d for channel "
			"measurement facility\n", format);
		return 1;
	}

	printk(KERN_INFO "Channel measurement facility using %s format (%s)\n",
		format_string, detect_string);
	return 0;
}

module_init(init_cmf);


MODULE_AUTHOR("Arnd Bergmann <[e-mail]>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("channel measurement facility base driver\n"
		   "Copyright 2003 IBM Corporation\n");

EXPORT_SYMBOL_GPL(enable_cmf);
EXPORT_SYMBOL_GPL(disable_cmf);
EXPORT_SYMBOL_GPL(cmf_read);
EXPORT_SYMBOL_GPL(cmf_readall);