Kernel Functions for Drivers rmallocmap(9F)
NAME
rmallocmap, rmallocmap_wait, rmfreemap - allocate and free
resource mapsSYNOPSIS
#include
#include
struct map *rmallocmap(size_t mapsize);
struct map *rmallocmap_wait(size_t mapsize);
void rmfreemap(struct map *mp);INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI).
PARAMETERS
mapsize Number of entries for the map.mp A pointer to the map structure to be deallo-
cated.DESCRIPTION
rmallocmap() dynamically allocates a resource map structure.
The argument mapsize defines the total number of entries inthe map. In particular, it is the total number of alloca-
tions that can be outstanding at any one time.rmallocmap() initializes the map but does not associate it
with the actual resource. In order to associate the map with the actual resource, a call to rmfree(9F) is used tomake the entirety of the actual resource available for allo-
cation, starting from the first index into the resource.Typically, the call to rmallocmap() is followed by a call to
rmfree(9F), passing the address of the map returned fromrmallocmap(), the total size of the resource, and the first
index into the actual resource.The resource map allocated by rmallocmap() can be used to
describe an arbitrary resource in whatever allocation units are appropriate, such as blocks, pages, or data structures. This resource can then be managed by the system bySunOS 5.11 Last change: 20 Nov 1996 1
Kernel Functions for Drivers rmallocmap(9F)
subsequent calls to rmalloc(9F), rmalloc_wait(9F), and
rmfree(9F).rmallocmap_wait() is similar to rmallocmap(), with the
exception that it will wait for space to become available if necessary. rmfreemap() deallocates a resource map structure previouslyallocated by rmallocmap() or rmallocmap_wait(). The argument
mp is a pointer to the map structure to be deallocated.RETURN VALUES
Upon successful completion, rmallocmap() and
rmallocmap_wait() return a pointer to the newly allocated
map structure. Upon failure, rmallocmap() returns a NULL
pointer.CONTEXT
rmallocmap() and rmfreemap() can be called from user, ker-
nel, or interrupt context.rmallocmap_wait() can only be called from user or kernel
context.SEE ALSO
rmalloc(9F), rmalloc_wait(9F), rmfree(9F)
Writing Device DriversSunOS 5.11 Last change: 20 Nov 1996 2