LLD mid level LLD
===-------------------=========--------------------===------
scsi_host_alloc() -->
-scsi_add_host() --------+
+scsi_add_host() ---->
+scsi_scan_host() -------+
|
slave_alloc()
slave_configure() --> scsi_adjust_queue_depth()
The hotplug concept may be extended to SCSI devices. Currently, when an
-HBA is added, the scsi_add_host() function causes a scan for SCSI devices
+HBA is added, the scsi_scan_host() function causes a scan for SCSI devices
attached to the HBA's SCSI transport. On newer SCSI transports the HBA
may become aware of a new SCSI device _after_ the scan has completed.
An LLD can use this sequence to make the mid level aware of a SCSI device:
Summary:
scsi_activate_tcq - turn on tag command queueing
scsi_add_device - creates new scsi device (lu) instance
- scsi_add_host - perform sysfs registration and SCSI bus scan.
+ scsi_add_host - perform sysfs registration and set up transport class
scsi_adjust_queue_depth - change the queue depth on a SCSI device
scsi_assign_lock - replace default host_lock with given lock
scsi_bios_ptable - return copy of block device's partition table
scsi_remove_device - detach and remove a SCSI device
scsi_remove_host - detach and remove all SCSI devices owned by host
scsi_report_bus_reset - report scsi _bus_ reset observed
+ scsi_scan_host - scan SCSI bus
scsi_track_queue_full - track successive QUEUE_FULL events
scsi_unblock_requests - allow further commands to be queued to given host
scsi_unregister - [calls scsi_host_put()]
* Might block: yes
*
* Notes: This call is usually performed internally during a scsi
- * bus scan when an HBA is added (i.e. scsi_add_host()). So it
+ * bus scan when an HBA is added (i.e. scsi_scan_host()). So it
* should only be called if the HBA becomes aware of a new scsi
- * device (lu) after scsi_add_host() has completed. If successful
- * this call we lead to slave_alloc() and slave_configure() callbacks
+ * device (lu) after scsi_scan_host() has completed. If successful
+ * this call can lead to slave_alloc() and slave_configure() callbacks
* into the LLD.
*
* Defined in: drivers/scsi/scsi_scan.c
/**
- * scsi_add_host - perform sysfs registration and SCSI bus scan.
+ * scsi_add_host - perform sysfs registration and set up transport class
* @shost: pointer to scsi host instance
* @dev: pointer to struct device of type scsi class
*
* Might block: no
*
* Notes: Only required in "hotplug initialization model" after a
- * successful call to scsi_host_alloc().
+ * successful call to scsi_host_alloc(). This function does not
+ * scan the bus; this can be done by calling scsi_scan_host() or
+ * in some other transport-specific way. The LLD must set up
+ * the transport template before calling this function and may only
+ * access the transport class data after this function has been called.
*
* Defined in: drivers/scsi/hosts.c
**/
* area for the LLD's exclusive use.
* Both associated refcounting objects have their refcount set to 1.
* Full registration (in sysfs) and a bus scan are performed later when
- * scsi_add_host() is called.
+ * scsi_add_host() and scsi_scan_host() are called.
*
* Defined in: drivers/scsi/hosts.c .
**/
void scsi_report_bus_reset(struct Scsi_Host * shost, int channel)
+/**
+ * scsi_scan_host - scan SCSI bus
+ * @shost: a pointer to a scsi host instance
+ *
+ * Might block: yes
+ *
+ * Notes: Should be called after scsi_add_host()
+ *
+ * Defined in: drivers/scsi/scsi_scan.c
+ **/
+void scsi_scan_host(struct Scsi_Host *shost)
+
+
/**
* scsi_track_queue_full - track successive QUEUE_FULL events on given
* device to determine if and when there is a need
*
* Defined in: drivers/scsi/scsi.c .
**/
-int scsi_track_queue_full(Scsi_Device *sdev, int depth)
+int scsi_track_queue_full(struct scsi_device *sdev, int depth)
/**
Christoph Hellwig <hch at infradead dot org>
Doug Ledford <dledford at redhat dot com>
Andries Brouwer <Andries dot Brouwer at cwi dot nl>
- Randy Dunlap <rddunlap at osdl dot org>
+ Randy Dunlap <rdunlap at xenotime dot net>
Alan Stern <stern at rowland dot harvard dot edu>