opensolaris man page for bp_mapin

bp_mapin(9F)						   Kernel Functions for Drivers 					      bp_mapin(9F)

NAME
       bp_mapin - allocate virtual address space

SYNOPSIS
       #include <sys/types.h>
       #include <sys/buf.h>

       void bp_mapin(struct buf *bp);

INTERFACE LEVEL
       Architecture independent level 1 (DDI/DKI).

PARAMETERS
       bp     Pointer to the buffer header structure.

DESCRIPTION
       bp_mapin()  is  used  to  map  virtual address space to a page list maintained by the buffer header during a paged- I/O request. bp_mapin()
       allocates system virtual address space, maps that space to  the	page  list,  and  returns  the	starting  address  of  the  space  in  the
       bp->b_un.b_addr field of the buf(9S) structure. Virtual address space is then deallocated using the bp_mapout(9F) function.

       If a null page list is encountered, bp_mapin() returns without allocating space and no mapping is performed.

CONTEXT
       bp_mapin() can be called from user and kernel contexts.

SEE ALSO
       bp_mapout(9F), buf(9S)

       Writing Device Drivers

SunOS 5.11							    13 Sep 1992 						      bp_mapin(9F)