--- /dev/null
+/*
+ * zfcp device driver
+ *
+ * Tracking of manually configured LUNs and helper functions to
+ * register the LUNs with the SCSI midlayer.
+ *
+ * Copyright IBM Corp. 2010
+ */
+
+#include "zfcp_def.h"
+#include "zfcp_ext.h"
+
+/**
+ * zfcp_unit_scsi_scan - Register LUN with SCSI midlayer
+ * @unit: The zfcp LUN/unit to register
+ *
+ * When the SCSI midlayer is not allowed to automatically scan and
+ * attach SCSI devices, zfcp has to register the single devices with
+ * the SCSI midlayer.
+ */
+void zfcp_unit_scsi_scan(struct zfcp_unit *unit)
+{
+ struct fc_rport *rport = unit->port->rport;
+ u64 lun;
+
+ lun = scsilun_to_int((struct scsi_lun *) &unit->fcp_lun);
+
+ if (rport && rport->port_state == FC_PORTSTATE_ONLINE)
+ scsi_scan_target(&rport->dev, 0, rport->scsi_target_id, lun, 1);
+}
+
+static void zfcp_unit_scsi_scan_work(struct work_struct *work)
+{
+ struct zfcp_unit *unit = container_of(work, struct zfcp_unit,
+ scsi_work);
+
+ zfcp_unit_scsi_scan(unit);
+ put_device(&unit->dev);
+}
+
+/**
+ * zfcp_unit_queue_scsi_scan - Register configured units on port
+ * @port: The zfcp_port where to register units
+ *
+ * After opening a port, all units configured on this port have to be
+ * registered with the SCSI midlayer. This function should be called
+ * after calling fc_remote_port_add, so that the fc_rport is already
+ * ONLINE and the call to scsi_scan_target runs the same way as the
+ * call in the FC transport class.
+ */
+void zfcp_unit_queue_scsi_scan(struct zfcp_port *port)
+{
+ struct zfcp_unit *unit;
+
+ read_lock_irq(&port->unit_list_lock);
+ list_for_each_entry(unit, &port->unit_list, list) {
+ get_device(&unit->dev);
+ if (scsi_queue_work(port->adapter->scsi_host,
+ &unit->scsi_work) <= 0)
+ put_device(&unit->dev);
+ }
+ read_unlock_irq(&port->unit_list_lock);
+}
+
+static struct zfcp_unit *_zfcp_unit_find(struct zfcp_port *port, u64 fcp_lun)
+{
+ struct zfcp_unit *unit;
+
+ list_for_each_entry(unit, &port->unit_list, list)
+ if (unit->fcp_lun == fcp_lun) {
+ get_device(&unit->dev);
+ return unit;
+ }
+
+ return NULL;
+}
+
+/**
+ * zfcp_unit_find - Find and return zfcp_unit with specified FCP LUN
+ * @port: zfcp_port where to look for the unit
+ * @fcp_lun: 64 Bit FCP LUN used to identify the zfcp_unit
+ *
+ * If zfcp_unit is found, a reference is acquired that has to be
+ * released later.
+ *
+ * Returns: Pointer to the zfcp_unit, or NULL if there is no zfcp_unit
+ * with the specified FCP LUN.
+ */
+struct zfcp_unit *zfcp_unit_find(struct zfcp_port *port, u64 fcp_lun)
+{
+ struct zfcp_unit *unit;
+
+ read_lock_irq(&port->unit_list_lock);
+ unit = _zfcp_unit_find(port, fcp_lun);
+ read_unlock_irq(&port->unit_list_lock);
+ return unit;
+}
+
+/**
+ * zfcp_unit_release - Drop reference to zfcp_port and free memory of zfcp_unit.
+ * @dev: pointer to device in zfcp_unit
+ */
+static void zfcp_unit_release(struct device *dev)
+{
+ struct zfcp_unit *unit = container_of(dev, struct zfcp_unit, dev);
+
+ atomic_dec(&unit->port->units);
+ kfree(unit);
+}
+
+/**
+ * zfcp_unit_enqueue - enqueue unit to unit list of a port.
+ * @port: pointer to port where unit is added
+ * @fcp_lun: FCP LUN of unit to be enqueued
+ * Returns: 0 success
+ *
+ * Sets up some unit internal structures and creates sysfs entry.
+ */
+int zfcp_unit_add(struct zfcp_port *port, u64 fcp_lun)
+{
+ struct zfcp_unit *unit;
+ int retval = 0;
+
+ mutex_lock(&zfcp_sysfs_port_units_mutex);
+ if (atomic_read(&port->units) == -1) {
+ /* port is already gone */
+ retval = -ENODEV;
+ goto out;
+ }
+
+ unit = zfcp_unit_find(port, fcp_lun);
+ if (unit) {
+ put_device(&unit->dev);
+ retval = -EEXIST;
+ goto out;
+ }
+
+ unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
+ if (!unit) {
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ unit->port = port;
+ unit->fcp_lun = fcp_lun;
+ unit->dev.parent = &port->dev;
+ unit->dev.release = zfcp_unit_release;
+ unit->dev.groups = zfcp_unit_attr_groups;
+ INIT_WORK(&unit->scsi_work, zfcp_unit_scsi_scan_work);
+
+ if (dev_set_name(&unit->dev, "0x%016llx",
+ (unsigned long long) fcp_lun)) {
+ kfree(unit);
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ if (device_register(&unit->dev)) {
+ put_device(&unit->dev);
+ retval = -ENOMEM;
+ goto out;
+ }
+
+ atomic_inc(&port->units); /* under zfcp_sysfs_port_units_mutex ! */
+
+ write_lock_irq(&port->unit_list_lock);
+ list_add_tail(&unit->list, &port->unit_list);
+ write_unlock_irq(&port->unit_list_lock);
+
+ zfcp_unit_scsi_scan(unit);
+
+out:
+ mutex_unlock(&zfcp_sysfs_port_units_mutex);
+ return retval;
+}
+
+/**
+ * zfcp_unit_sdev - Return SCSI device for zfcp_unit
+ * @unit: The zfcp_unit where to get the SCSI device for
+ *
+ * Returns: scsi_device pointer on success, NULL if there is no SCSI
+ * device for this zfcp_unit
+ *
+ * On success, the caller also holds a reference to the SCSI device
+ * that must be released with scsi_device_put.
+ */
+struct scsi_device *zfcp_unit_sdev(struct zfcp_unit *unit)
+{
+ struct Scsi_Host *shost;
+ struct zfcp_port *port;
+ u64 lun;
+
+ lun = scsilun_to_int((struct scsi_lun *) &unit->fcp_lun);
+ port = unit->port;
+ shost = port->adapter->scsi_host;
+ return scsi_device_lookup(shost, 0, port->starget_id, lun);
+}
+
+/**
+ * zfcp_unit_sdev_status - Return zfcp LUN status for SCSI device
+ * @unit: The unit to lookup the SCSI device for
+ *
+ * Returns the zfcp LUN status field of the SCSI device if the SCSI device
+ * for the zfcp_unit exists, 0 otherwise.
+ */
+unsigned int zfcp_unit_sdev_status(struct zfcp_unit *unit)
+{
+ unsigned int status = 0;
+ struct scsi_device *sdev;
+ struct zfcp_scsi_dev *zfcp_sdev;
+
+ sdev = zfcp_unit_sdev(unit);
+ if (sdev) {
+ zfcp_sdev = sdev_to_zfcp(sdev);
+ status = atomic_read(&zfcp_sdev->status);
+ scsi_device_put(sdev);
+ }
+
+ return status;
+}
+
+/**
+ * zfcp_unit_remove - Remove entry from list of configured units
+ * @port: The port where to remove the unit from the configuration
+ * @fcp_lun: The 64 bit LUN of the unit to remove
+ *
+ * Returns: -EINVAL if a unit with the specified LUN does not exist,
+ * 0 on success.
+ */
+int zfcp_unit_remove(struct zfcp_port *port, u64 fcp_lun)
+{
+ struct zfcp_unit *unit;
+ struct scsi_device *sdev;
+
+ write_lock_irq(&port->unit_list_lock);
+ unit = _zfcp_unit_find(port, fcp_lun);
+ if (unit)
+ list_del(&unit->list);
+ write_unlock_irq(&port->unit_list_lock);
+
+ if (!unit)
+ return -EINVAL;
+
+ sdev = zfcp_unit_sdev(unit);
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ }
+
+ put_device(&unit->dev);
+
+ device_unregister(&unit->dev);
+
+ return 0;
+}
Code Review / kvmfornfv.git / blobdiff