From 7970634b81a6e3561954517bca42615542c4535b Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 21 May 2008 15:54:12 -0500 Subject: [PATCH] [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 Signed-off-by: James Bottomley --- drivers/infiniband/ulp/iser/iscsi_iser.c | 2 +- drivers/scsi/iscsi_tcp.c | 2 +- drivers/scsi/libiscsi.c | 4 +- drivers/scsi/scsi_transport_iscsi.c | 129 +++++++++++++++++------ include/scsi/libiscsi.h | 2 +- include/scsi/scsi_transport_iscsi.h | 6 +- 6 files changed, 106 insertions(+), 39 deletions(-) diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c index 86d9c42f0d33..3a89039e9a96 100644 --- a/drivers/infiniband/ulp/iser/iscsi_iser.c +++ b/drivers/infiniband/ulp/iser/iscsi_iser.c @@ -437,7 +437,7 @@ iscsi_iser_session_create(struct Scsi_Host *shost, cls_session = iscsi_session_setup(&iscsi_iser_transport, shost, ISCSI_DEF_XMIT_CMDS_MAX, sizeof(struct iscsi_iser_task), - initial_cmdsn); + initial_cmdsn, 0); if (!cls_session) goto remove_host; session = cls_session->dd_data; diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c index 33cd0ca7cc8d..aa3c7f0c550d 100644 --- a/drivers/scsi/iscsi_tcp.c +++ b/drivers/scsi/iscsi_tcp.c @@ -1868,7 +1868,7 @@ iscsi_tcp_session_create(struct Scsi_Host *shost, uint16_t cmds_max, cls_session = iscsi_session_setup(&iscsi_tcp_transport, shost, cmds_max, sizeof(struct iscsi_tcp_task), - initial_cmdsn); + initial_cmdsn, 0); if (!cls_session) goto remove_host; session = cls_session->dd_data; diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 92ee6d94aaf9..e88b726ab2e0 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -1897,7 +1897,7 @@ EXPORT_SYMBOL_GPL(iscsi_host_free); struct iscsi_cls_session * iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost, uint16_t scsi_cmds_max, int cmd_task_size, - uint32_t initial_cmdsn) + uint32_t initial_cmdsn, unsigned int id) { struct iscsi_session *session; struct iscsi_cls_session *cls_session; @@ -1957,7 +1957,7 @@ iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost, if (!try_module_get(iscsit->owner)) goto module_get_fail; - if (iscsi_add_session(cls_session, 0)) + if (iscsi_add_session(cls_session, id)) goto cls_session_fail; return cls_session; diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 6b8516a0970b..ac9d298f54e7 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -119,9 +119,8 @@ static int iscsi_setup_host(struct transport_container *tc, struct device *dev, 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 @@ int iscsi_scan_finished(struct Scsi_Host *shost, unsigned long time) } 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 @@ static void iscsi_scan_session(struct work_struct *work) 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 @@ static void __iscsi_unbind_session(struct work_struct *work) 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 @@ iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport, 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 @@ iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport, } 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 @@ int iscsi_add_session(struct iscsi_cls_session *session, unsigned int target_id) 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; diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h index 176353c117b6..13c92d7ba969 100644 --- a/include/scsi/libiscsi.h +++ b/include/scsi/libiscsi.h @@ -331,7 +331,7 @@ extern void iscsi_host_free(struct Scsi_Host *shost); */ extern struct iscsi_cls_session * iscsi_session_setup(struct iscsi_transport *, struct Scsi_Host *shost, - uint16_t, int, uint32_t); + uint16_t, int, uint32_t, unsigned int); extern void iscsi_session_teardown(struct iscsi_cls_session *); extern void iscsi_session_recovery_timedout(struct iscsi_cls_session *); extern int iscsi_set_param(struct iscsi_cls_conn *cls_conn, diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h index 0553240796e9..d6b823195563 100644 --- a/include/scsi/scsi_transport_iscsi.h +++ b/include/scsi/scsi_transport_iscsi.h @@ -161,9 +161,10 @@ enum { ISCSI_SESSION_FREE, }; +#define ISCSI_MAX_TARGET -1 + struct iscsi_cls_session { struct list_head sess_list; /* item in session_list */ - struct list_head host_list; struct iscsi_transport *transport; spinlock_t lock; struct work_struct block_work; @@ -175,7 +176,7 @@ struct iscsi_cls_session { int recovery_tmo; struct delayed_work recovery_work; - int target_id; + unsigned int target_id; int state; int sid; /* session id */ @@ -193,7 +194,6 @@ struct iscsi_cls_session { iscsi_dev_to_session(_stgt->dev.parent) struct iscsi_cls_host { - struct list_head sessions; atomic_t nr_scans; struct mutex mutex; struct workqueue_struct *scan_workq;