dasd_devmap.c

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	}

	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
	cdev->dev.driver_data = device;
	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);

	return device;
}

/*
 * Wait queue for dasd_delete_device waits.
 */
static DECLARE_WAIT_QUEUE_HEAD(dasd_delete_wq);

/*
 * Remove a dasd device structure. The passed referenced
 * is destroyed.
 */
void
dasd_delete_device(struct dasd_device *device)
{
	struct ccw_device *cdev;
	struct dasd_devmap *devmap;
	unsigned long flags;

	/* First remove device pointer from devmap. */
	devmap = dasd_find_busid(device->cdev->dev.bus_id);
	BUG_ON(IS_ERR(devmap));
	spin_lock(&dasd_devmap_lock);
	if (devmap->device != device) {
		spin_unlock(&dasd_devmap_lock);
		dasd_put_device(device);
		return;
	}
	devmap->device = NULL;
	spin_unlock(&dasd_devmap_lock);

	/* Disconnect dasd_device structure from ccw_device structure. */
	spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
	device->cdev->dev.driver_data = NULL;
	spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);

	/*
	 * Drop ref_count by 3, one for the devmap reference, one for
	 * the cdev reference and one for the passed reference.
	 */
	atomic_sub(3, &device->ref_count);

	/* Wait for reference counter to drop to zero. */
	wait_event(dasd_delete_wq, atomic_read(&device->ref_count) == 0);

	/* Disconnect dasd_device structure from ccw_device structure. */
	cdev = device->cdev;
	device->cdev = NULL;

	/* Put ccw_device structure. */
	put_device(&cdev->dev);

	/* Now the device structure can be freed. */
	dasd_free_device(device);
}

/*
 * Reference counter dropped to zero. Wake up waiter
 * in dasd_delete_device.
 */
void
dasd_put_device_wake(struct dasd_device *device)
{
	wake_up(&dasd_delete_wq);
}

/*
 * Return dasd_device structure associated with cdev.
 * This function needs to be called with the ccw device
 * lock held. It can be used from interrupt context.
 */
struct dasd_device *
dasd_device_from_cdev_locked(struct ccw_device *cdev)
{
	struct dasd_device *device = cdev->dev.driver_data;

	if (!device)
		return ERR_PTR(-ENODEV);
	dasd_get_device(device);
	return device;
}

/*
 * Return dasd_device structure associated with cdev.
 */
struct dasd_device *
dasd_device_from_cdev(struct ccw_device *cdev)
{
	struct dasd_device *device;
	unsigned long flags;

	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
	device = dasd_device_from_cdev_locked(cdev);
	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
	return device;
}

/*
 * SECTION: files in sysfs
 */

/*
 * readonly controls the readonly status of a dasd
 */
static ssize_t
dasd_ro_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	int ro_flag;

	devmap = dasd_find_busid(dev->bus_id);
	if (!IS_ERR(devmap))
		ro_flag = (devmap->features & DASD_FEATURE_READONLY) != 0;
	else
		ro_flag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_READONLY) != 0;
	return snprintf(buf, PAGE_SIZE, ro_flag ? "1\n" : "0\n");
}

static ssize_t
dasd_ro_store(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct dasd_devmap *devmap;
	int val;
	char *endp;

	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);

	val = simple_strtoul(buf, &endp, 0);
	if (((endp + 1) < (buf + count)) || (val > 1))
		return -EINVAL;

	spin_lock(&dasd_devmap_lock);
	if (val)
		devmap->features |= DASD_FEATURE_READONLY;
	else
		devmap->features &= ~DASD_FEATURE_READONLY;
	if (devmap->device)
		devmap->device->features = devmap->features;
	if (devmap->device && devmap->device->gdp)
		set_disk_ro(devmap->device->gdp, val);
	spin_unlock(&dasd_devmap_lock);
	return count;
}

static DEVICE_ATTR(readonly, 0644, dasd_ro_show, dasd_ro_store);
/*
 * erplog controls the logging of ERP related data
 * (e.g. failing channel programs).
 */
static ssize_t
dasd_erplog_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	int erplog;

	devmap = dasd_find_busid(dev->bus_id);
	if (!IS_ERR(devmap))
		erplog = (devmap->features & DASD_FEATURE_ERPLOG) != 0;
	else
		erplog = (DASD_FEATURE_DEFAULT & DASD_FEATURE_ERPLOG) != 0;
	return snprintf(buf, PAGE_SIZE, erplog ? "1\n" : "0\n");
}

static ssize_t
dasd_erplog_store(struct device *dev, struct device_attribute *attr,
	      const char *buf, size_t count)
{
	struct dasd_devmap *devmap;
	int val;
	char *endp;

	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);

	val = simple_strtoul(buf, &endp, 0);
	if (((endp + 1) < (buf + count)) || (val > 1))
		return -EINVAL;

	spin_lock(&dasd_devmap_lock);
	if (val)
		devmap->features |= DASD_FEATURE_ERPLOG;
	else
		devmap->features &= ~DASD_FEATURE_ERPLOG;
	if (devmap->device)
		devmap->device->features = devmap->features;
	spin_unlock(&dasd_devmap_lock);
	return count;
}

static DEVICE_ATTR(erplog, 0644, dasd_erplog_show, dasd_erplog_store);

/*
 * use_diag controls whether the driver should use diag rather than ssch
 * to talk to the device
 */
static ssize_t
dasd_use_diag_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	int use_diag;

	devmap = dasd_find_busid(dev->bus_id);
	if (!IS_ERR(devmap))
		use_diag = (devmap->features & DASD_FEATURE_USEDIAG) != 0;
	else
		use_diag = (DASD_FEATURE_DEFAULT & DASD_FEATURE_USEDIAG) != 0;
	return sprintf(buf, use_diag ? "1\n" : "0\n");
}

static ssize_t
dasd_use_diag_store(struct device *dev, struct device_attribute *attr,
		    const char *buf, size_t count)
{
	struct dasd_devmap *devmap;
	ssize_t rc;
	int val;
	char *endp;

	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);

	val = simple_strtoul(buf, &endp, 0);
	if (((endp + 1) < (buf + count)) || (val > 1))
		return -EINVAL;

	spin_lock(&dasd_devmap_lock);
	/* Changing diag discipline flag is only allowed in offline state. */
	rc = count;
	if (!devmap->device) {
		if (val)
			devmap->features |= DASD_FEATURE_USEDIAG;
		else
			devmap->features &= ~DASD_FEATURE_USEDIAG;
	} else
		rc = -EPERM;
	spin_unlock(&dasd_devmap_lock);
	return rc;
}

static DEVICE_ATTR(use_diag, 0644, dasd_use_diag_show, dasd_use_diag_store);

static ssize_t
dasd_discipline_show(struct device *dev, struct device_attribute *attr,
		     char *buf)
{
	struct dasd_device *device;
	ssize_t len;

	device = dasd_device_from_cdev(to_ccwdev(dev));
	if (!IS_ERR(device) && device->discipline) {
		len = snprintf(buf, PAGE_SIZE, "%s\n",
			       device->discipline->name);
		dasd_put_device(device);
	} else
		len = snprintf(buf, PAGE_SIZE, "none\n");
	return len;
}

static DEVICE_ATTR(discipline, 0444, dasd_discipline_show, NULL);

static ssize_t
dasd_device_status_show(struct device *dev, struct device_attribute *attr,
		     char *buf)
{
	struct dasd_device *device;
	ssize_t len;

	device = dasd_device_from_cdev(to_ccwdev(dev));
	if (!IS_ERR(device)) {
		switch (device->state) {
		case DASD_STATE_NEW:
			len = snprintf(buf, PAGE_SIZE, "new\n");
			break;
		case DASD_STATE_KNOWN:
			len = snprintf(buf, PAGE_SIZE, "detected\n");
			break;
		case DASD_STATE_BASIC:
			len = snprintf(buf, PAGE_SIZE, "basic\n");
			break;
		case DASD_STATE_UNFMT:
			len = snprintf(buf, PAGE_SIZE, "unformatted\n");
			break;
		case DASD_STATE_READY:
			len = snprintf(buf, PAGE_SIZE, "ready\n");
			break;
		case DASD_STATE_ONLINE:
			len = snprintf(buf, PAGE_SIZE, "online\n");
			break;
		default:
			len = snprintf(buf, PAGE_SIZE, "no stat\n");
			break;
		}
		dasd_put_device(device);
	} else
		len = snprintf(buf, PAGE_SIZE, "unknown\n");
	return len;
}

static DEVICE_ATTR(status, 0444, dasd_device_status_show, NULL);

static ssize_t
dasd_alias_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	int alias;

	devmap = dasd_find_busid(dev->bus_id);
	spin_lock(&dasd_devmap_lock);
	if (!IS_ERR(devmap))
		alias = devmap->uid.alias;
	else
		alias = 0;
	spin_unlock(&dasd_devmap_lock);

	return sprintf(buf, alias ? "1\n" : "0\n");
}

static DEVICE_ATTR(alias, 0444, dasd_alias_show, NULL);

static ssize_t
dasd_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	char *vendor;

	devmap = dasd_find_busid(dev->bus_id);
	spin_lock(&dasd_devmap_lock);
	if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
		vendor = devmap->uid.vendor;
	else
		vendor = "";
	spin_unlock(&dasd_devmap_lock);

	return snprintf(buf, PAGE_SIZE, "%s\n", vendor);
}

static DEVICE_ATTR(vendor, 0444, dasd_vendor_show, NULL);

#define UID_STRLEN ( /* vendor */ 3 + 1 + /* serial    */ 14 + 1 +\
		     /* SSID   */ 4 + 1 + /* unit addr */ 2 + 1)

static ssize_t
dasd_uid_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	char uid[UID_STRLEN];

	devmap = dasd_find_busid(dev->bus_id);
	spin_lock(&dasd_devmap_lock);
	if (!IS_ERR(devmap) && strlen(devmap->uid.vendor) > 0)
		snprintf(uid, sizeof(uid), "%s.%s.%04x.%02x",
			 devmap->uid.vendor, devmap->uid.serial,
			 devmap->uid.ssid, devmap->uid.unit_addr);
	else
		uid[0] = 0;
	spin_unlock(&dasd_devmap_lock);

	return snprintf(buf, PAGE_SIZE, "%s\n", uid);
}

static DEVICE_ATTR(uid, 0444, dasd_uid_show, NULL);

/*
 * extended error-reporting
 */
static ssize_t
dasd_eer_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct dasd_devmap *devmap;
	int eer_flag;

	devmap = dasd_find_busid(dev->bus_id);
	if (!IS_ERR(devmap) && devmap->device)
		eer_flag = dasd_eer_enabled(devmap->device);
	else
		eer_flag = 0;
	return snprintf(buf, PAGE_SIZE, eer_flag ? "1\n" : "0\n");
}

static ssize_t
dasd_eer_store(struct device *dev, struct device_attribute *attr,
	       const char *buf, size_t count)
{
	struct dasd_devmap *devmap;
	int val, rc;
	char *endp;

	devmap = dasd_devmap_from_cdev(to_ccwdev(dev));
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);
	if (!devmap->device)
		return -ENODEV;

	val = simple_strtoul(buf, &endp, 0);
	if (((endp + 1) < (buf + count)) || (val > 1))
		return -EINVAL;

	if (val) {
		rc = dasd_eer_enable(devmap->device);
		if (rc)
			return rc;
	} else
		dasd_eer_disable(devmap->device);
	return count;
}

static DEVICE_ATTR(eer_enabled, 0644, dasd_eer_show, dasd_eer_store);

static struct attribute * dasd_attrs[] = {
	&dev_attr_readonly.attr,
	&dev_attr_discipline.attr,
	&dev_attr_status.attr,
	&dev_attr_alias.attr,
	&dev_attr_vendor.attr,
	&dev_attr_uid.attr,
	&dev_attr_use_diag.attr,
	&dev_attr_eer_enabled.attr,
	&dev_attr_erplog.attr,
	NULL,
};

static struct attribute_group dasd_attr_group = {
	.attrs = dasd_attrs,
};

/*
 * Return copy of the device unique identifier.
 */
int
dasd_get_uid(struct ccw_device *cdev, struct dasd_uid *uid)
{
	struct dasd_devmap *devmap;

	devmap = dasd_find_busid(cdev->dev.bus_id);
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);
	spin_lock(&dasd_devmap_lock);
	*uid = devmap->uid;
	spin_unlock(&dasd_devmap_lock);
	return 0;
}

/*
 * Register the given device unique identifier into devmap struct.
 * In addition check if the related storage server subsystem ID is already
 * contained in the dasd_server_ssid_list. If subsystem ID is not contained,
 * create new entry.
 * Return 0 if server was already in serverlist,
 *	  1 if the server was added successful
 *	 <0 in case of error.
 */
int
dasd_set_uid(struct ccw_device *cdev, struct dasd_uid *uid)
{
	struct dasd_devmap *devmap;
	struct dasd_server_ssid_map *srv, *tmp;

	devmap = dasd_find_busid(cdev->dev.bus_id);
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);

	/* generate entry for server_ssid_map */
	srv = (struct dasd_server_ssid_map *)
		kzalloc(sizeof(struct dasd_server_ssid_map), GFP_KERNEL);
	if (!srv)
		return -ENOMEM;
	strncpy(srv->sid.vendor, uid->vendor, sizeof(srv->sid.vendor) - 1);
	strncpy(srv->sid.serial, uid->serial, sizeof(srv->sid.serial) - 1);
	srv->sid.ssid = uid->ssid;

	/* server is already contained ? */
	spin_lock(&dasd_devmap_lock);
	devmap->uid = *uid;
	list_for_each_entry(tmp, &dasd_server_ssid_list, list) {
		if (!memcmp(&srv->sid, &tmp->sid,
			    sizeof(struct system_id))) {
			kfree(srv);
			srv = NULL;
			break;
		}
	}

	/* add servermap to serverlist */
	if (srv)
		list_add(&srv->list, &dasd_server_ssid_list);
	spin_unlock(&dasd_devmap_lock);

	return (srv ? 1 : 0);
}
EXPORT_SYMBOL_GPL(dasd_set_uid);

/*
 * Return value of the specified feature.
 */
int
dasd_get_feature(struct ccw_device *cdev, int feature)
{
	struct dasd_devmap *devmap;

	devmap = dasd_find_busid(cdev->dev.bus_id);
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);

	return ((devmap->features & feature) != 0);
}

/*
 * Set / reset given feature.
 * Flag indicates wether to set (!=0) or the reset (=0) the feature.
 */
int
dasd_set_feature(struct ccw_device *cdev, int feature, int flag)
{
	struct dasd_devmap *devmap;

	devmap = dasd_find_busid(cdev->dev.bus_id);
	if (IS_ERR(devmap))
		return PTR_ERR(devmap);

	spin_lock(&dasd_devmap_lock);
	if (flag)
		devmap->features |= feature;
	else
		devmap->features &= ~feature;
	if (devmap->device)
		devmap->device->features = devmap->features;
	spin_unlock(&dasd_devmap_lock);
	return 0;
}


int
dasd_add_sysfs_files(struct ccw_device *cdev)
{
	return sysfs_create_group(&cdev->dev.kobj, &dasd_attr_group);
}

void
dasd_remove_sysfs_files(struct ccw_device *cdev)
{
	sysfs_remove_group(&cdev->dev.kobj, &dasd_attr_group);
}


int
dasd_devmap_init(void)
{
	int i;

	/* Initialize devmap structures. */
	dasd_max_devindex = 0;
	for (i = 0; i < 256; i++)
		INIT_LIST_HEAD(&dasd_hashlists[i]);

	/* Initialize servermap structure. */
	INIT_LIST_HEAD(&dasd_server_ssid_list);
	return 0;
}

void
dasd_devmap_exit(void)
{
	dasd_forget_ranges();
}