[SCSI] iscsi class: user device_for_each_child instead of duplicating session list
Currently we duplicate the list of sessions, because we were using the
test for if a session was on the host list to indicate if the session
was bound or unbound. We can instead use the target_id and fix up
the class so that drivers like bnx2i do not have to manage the target id
space.
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 6b8516a..ac9d298 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -119,9 +119,8 @@
struct iscsi_cls_host *ihost = shost->shost_data;
memset(ihost, 0, sizeof(*ihost));
- INIT_LIST_HEAD(&ihost->sessions);
- mutex_init(&ihost->mutex);
atomic_set(&ihost->nr_scans, 0);
+ mutex_init(&ihost->mutex);
snprintf(ihost->scan_workq_name, KOBJ_NAME_LEN, "iscsi_scan_%d",
shost->host_no);
@@ -316,22 +315,61 @@
}
EXPORT_SYMBOL_GPL(iscsi_scan_finished);
+struct iscsi_scan_data {
+ unsigned int channel;
+ unsigned int id;
+ unsigned int lun;
+};
+
+static int iscsi_user_scan_session(struct device *dev, void *data)
+{
+ struct iscsi_scan_data *scan_data = data;
+ struct iscsi_cls_session *session;
+ struct Scsi_Host *shost;
+ struct iscsi_cls_host *ihost;
+ unsigned long flags;
+ unsigned int id;
+
+ if (!iscsi_is_session_dev(dev))
+ return 0;
+
+ session = iscsi_dev_to_session(dev);
+ shost = iscsi_session_to_shost(session);
+ ihost = shost->shost_data;
+
+ mutex_lock(&ihost->mutex);
+ spin_lock_irqsave(&session->lock, flags);
+ if (session->state != ISCSI_SESSION_LOGGED_IN) {
+ spin_unlock_irqrestore(&session->lock, flags);
+ mutex_unlock(&ihost->mutex);
+ return 0;
+ }
+ id = session->target_id;
+ spin_unlock_irqrestore(&session->lock, flags);
+
+ if (id != ISCSI_MAX_TARGET) {
+ if ((scan_data->channel == SCAN_WILD_CARD ||
+ scan_data->channel == 0) &&
+ (scan_data->id == SCAN_WILD_CARD ||
+ scan_data->id == id))
+ scsi_scan_target(&session->dev, 0, id,
+ scan_data->lun, 1);
+ }
+ mutex_unlock(&ihost->mutex);
+ return 0;
+}
+
static int iscsi_user_scan(struct Scsi_Host *shost, uint channel,
uint id, uint lun)
{
- struct iscsi_cls_host *ihost = shost->shost_data;
- struct iscsi_cls_session *session;
+ struct iscsi_scan_data scan_data;
- mutex_lock(&ihost->mutex);
- list_for_each_entry(session, &ihost->sessions, host_list) {
- if ((channel == SCAN_WILD_CARD || channel == 0) &&
- (id == SCAN_WILD_CARD || id == session->target_id))
- scsi_scan_target(&session->dev, 0,
- session->target_id, lun, 1);
- }
- mutex_unlock(&ihost->mutex);
+ scan_data.channel = channel;
+ scan_data.id = id;
+ scan_data.lun = lun;
- return 0;
+ return device_for_each_child(&shost->shost_gendev, &scan_data,
+ iscsi_user_scan_session);
}
static void iscsi_scan_session(struct work_struct *work)
@@ -340,18 +378,13 @@
container_of(work, struct iscsi_cls_session, scan_work);
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_cls_host *ihost = shost->shost_data;
- unsigned long flags;
+ struct iscsi_scan_data scan_data;
- spin_lock_irqsave(&session->lock, flags);
- if (session->state != ISCSI_SESSION_LOGGED_IN) {
- spin_unlock_irqrestore(&session->lock, flags);
- goto done;
- }
- spin_unlock_irqrestore(&session->lock, flags);
+ scan_data.channel = 0;
+ scan_data.id = SCAN_WILD_CARD;
+ scan_data.lun = SCAN_WILD_CARD;
- scsi_scan_target(&session->dev, 0, session->target_id,
- SCAN_WILD_CARD, 1);
-done:
+ iscsi_user_scan_session(&session->dev, &scan_data);
atomic_dec(&ihost->nr_scans);
}
@@ -460,14 +493,18 @@
unbind_work);
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_cls_host *ihost = shost->shost_data;
+ unsigned long flags;
/* Prevent new scans and make sure scanning is not in progress */
mutex_lock(&ihost->mutex);
- if (list_empty(&session->host_list)) {
+ spin_lock_irqsave(&session->lock, flags);
+ if (session->target_id == ISCSI_MAX_TARGET) {
+ spin_unlock_irqrestore(&session->lock, flags);
mutex_unlock(&ihost->mutex);
return;
}
- list_del_init(&session->host_list);
+ session->target_id = ISCSI_MAX_TARGET;
+ spin_unlock_irqrestore(&session->lock, flags);
mutex_unlock(&ihost->mutex);
scsi_remove_target(&session->dev);
@@ -497,7 +534,6 @@
session->recovery_tmo = 120;
session->state = ISCSI_SESSION_FREE;
INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout);
- INIT_LIST_HEAD(&session->host_list);
INIT_LIST_HEAD(&session->sess_list);
INIT_WORK(&session->unblock_work, __iscsi_unblock_session);
INIT_WORK(&session->block_work, __iscsi_block_session);
@@ -516,16 +552,51 @@
}
EXPORT_SYMBOL_GPL(iscsi_alloc_session);
+static int iscsi_get_next_target_id(struct device *dev, void *data)
+{
+ struct iscsi_cls_session *session;
+ unsigned long flags;
+ int err = 0;
+
+ if (!iscsi_is_session_dev(dev))
+ return 0;
+
+ session = iscsi_dev_to_session(dev);
+ spin_lock_irqsave(&session->lock, flags);
+ if (*((unsigned int *) data) == session->target_id)
+ err = -EEXIST;
+ spin_unlock_irqrestore(&session->lock, flags);
+ return err;
+}
+
int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id)
{
struct Scsi_Host *shost = iscsi_session_to_shost(session);
struct iscsi_cls_host *ihost;
unsigned long flags;
+ unsigned int id = target_id;
int err;
ihost = shost->shost_data;
session->sid = atomic_add_return(1, &iscsi_session_nr);
- session->target_id = target_id;
+
+ if (id == ISCSI_MAX_TARGET) {
+ for (id = 0; id < ISCSI_MAX_TARGET; id++) {
+ err = device_for_each_child(&shost->shost_gendev, &id,
+ iscsi_get_next_target_id);
+ if (!err)
+ break;
+ }
+
+ if (id == ISCSI_MAX_TARGET) {
+ iscsi_cls_session_printk(KERN_ERR, session,
+ "Too many iscsi targets. Max "
+ "number of targets is %d.\n",
+ ISCSI_MAX_TARGET - 1);
+ goto release_host;
+ }
+ }
+ session->target_id = id;
snprintf(session->dev.bus_id, BUS_ID_SIZE, "session%u",
session->sid);
@@ -541,10 +612,6 @@
list_add(&session->sess_list, &sesslist);
spin_unlock_irqrestore(&sesslock, flags);
- mutex_lock(&ihost->mutex);
- list_add(&session->host_list, &ihost->sessions);
- mutex_unlock(&ihost->mutex);
-
iscsi_session_event(session, ISCSI_KEVENT_CREATE_SESSION);
return 0;