xsb(D4sdi)

xsb -- SDI linking structure

Synopsis

   #include <sys/sdi.h>

Description

The xsb structure is used by SDI to maintain the connection between the sb(D4sdi) structure, the target owner structure, and the HBA private data structure. The sb structure is the first element.

Structure definition

The xsb structure is defined as follows:

   struct xsb {
       struct sb       sb;
       struct hbadata  *hbadata_p;
       struct owner    *owner_p;
       struct sb_extra extra;
   };

The sb_extra structure is defined as follows:

   struct sense        sb_sense;
   unsigned long       sb_data_type;
   paddr_t             *sb_datapt;
   buf_t               *sb_bufp;
   void                *sb_idatap;
   };

Structure members

sb: Pointer to the sb(D4sdi) structure.
hbadata_p: Pointer to the hbadata(D4sdi) structure.
owner_p: Pointer to the owner(D4sdi) structure.
extra: Pointer to the sb_extra structure that contains additional information that is used internally by SDI. Drivers access this information only through the defined kernel functions.
sb_sense: HBA sense data passed to the target driver on completion, if the command completed with an error. Accessed only through the sdi_sense_ptr(D3sdi) function.
sb_data_type: Accessed with the sdi_data_type(D3sdi) function.
sb_datapt: Accessed with the sdi_datapt_ptr(D3sdi) function.
sb_bufp: Accessed only through the sdi_buf_ptr(D3sdi) kernel function.
*sb_idatap: Pointer to target-driver specific instance pointer. Accessed through the sdi_get_idata_ptr(D3sdi) and sdi_set_idata_ptr(D3sdi) functions.

Usage

When SDI allocates the sb command block, the xsb is the actual structure that is allocated. The SDI interface functions are passed the xsb pointer, cast as the sb pointer, because all elements beyond the sb structure are for SDI internal use only. External to SDI, the owner block and hbadata pointers in this structure are not visible.

Applicable hardware

All.

Version applicability

sdi: 2, 3, 4

References

hbadata(D4sdi), owner(D4sdi), sb(D4sdi)