[SCSI] allow the HBA to reserve target and device private areas
This patch basically allows any HBA attached to the SPI transport class
to declare an extra area which the mid-layer will allocate as part of
its device and target allocations.
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/include/scsi/scsi_transport.h b/include/scsi/scsi_transport.h
index 2dcee7a..a4f1837 100644
--- a/include/scsi/scsi_transport.h
+++ b/include/scsi/scsi_transport.h
@@ -21,6 +21,7 @@
#define SCSI_TRANSPORT_H
#include <linux/transport_class.h>
+#include <scsi/scsi_host.h>
struct scsi_transport_template {
/* the attribute containers */
@@ -32,8 +33,11 @@
* space of this size will be left at the end of the
* scsi_* structure */
int device_size;
+ int device_private_offset;
int target_size;
+ int target_private_offset;
int host_size;
+ /* no private offset for the host; there's an alternative mechanism */
/*
* True if the transport wants to use a host-based work-queue
@@ -45,4 +49,38 @@
dev_to_shost((tc)->dev)
+/* Private area maintenance. The driver requested allocations come
+ * directly after the transport class allocations (if any). The idea
+ * is that you *must* call these only once. The code assumes that the
+ * initial values are the ones the transport specific code requires */
+static inline void
+scsi_transport_reserve_target(struct scsi_transport_template * t, int space)
+{
+ BUG_ON(t->target_private_offset != 0);
+ t->target_private_offset = ALIGN(t->target_size, sizeof(void *));
+ t->target_size = t->target_private_offset + space;
+}
+static inline void
+scsi_transport_reserve_device(struct scsi_transport_template * t, int space)
+{
+ BUG_ON(t->device_private_offset != 0);
+ t->device_private_offset = ALIGN(t->device_size, sizeof(void *));
+ t->device_size = t->device_private_offset + space;
+}
+static inline void *
+scsi_transport_target_data(struct scsi_target *starget)
+{
+ struct Scsi_Host *shost = dev_to_shost(&starget->dev);
+ return (u8 *)starget->starget_data
+ + shost->transportt->target_private_offset;
+
+}
+static inline void *
+scsi_transport_device_data(struct scsi_device *sdev)
+{
+ struct Scsi_Host *shost = sdev->host;
+ return (u8 *)sdev->sdev_data
+ + shost->transportt->device_private_offset;
+}
+
#endif /* SCSI_TRANSPORT_H */