NAME
rman, rman_activate_resource, rman_adjust_resource, rman_deactivate_resource, rman_fini, rman_init, rman_init_from_resource, rman_is_region_manager, rman_manage_region, rman_first_free_region, rman_last_free_region, rman_release_resource, rman_reserve_resource, rman_reserve_resource_bound, rman_make_alignment_flags, rman_get_start, rman_get_end, rman_get_device, rman_get_size, rman_get_flags, rman_set_mapping, rman_get_mapping, rman_set_virtual, rman_get_virtual, rman_set_bustag, rman_get_bustag, rman_set_bushandle, rman_get_bushandle, rman_set_rid, rman_get_rid — resource management functionsSYNOPSIS
#include <sys/types.h>#include <sys/rman.h> int
rman_activate_resource(struct resource *r); int
rman_adjust_resource(struct resource *r, rman_res_t start, rman_res_t end); int
rman_deactivate_resource(struct resource *r); int
rman_fini(struct rman *rm); int
rman_init(struct rman *rm); int
rman_init_from_resource(struct rman *rm, struct resource *r); int
rman_is_region_manager(struct resource *r, struct rman *rm); int
rman_manage_region(struct rman *rm, rman_res_t start, rman_res_t end); int
rman_first_free_region(struct rman *rm, rman_res_t *start, rman_res_t *end); int
rman_last_free_region(struct rman *rm, rman_res_t *start, rman_res_t *end); int
rman_release_resource(struct resource *r); struct resource *
rman_reserve_resource(struct rman *rm, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags, struct device *dev); struct resource *
rman_reserve_resource_bound(struct rman *rm, rman_res_t start, rman_res_t end, rman_res_t count, rman_res_t bound, u_int flags, struct device *dev); uint32_t
rman_make_alignment_flags(uint32_t size); rman_res_t
rman_get_start(struct resource *r); rman_res_t
rman_get_end(struct resource *r); struct device *
rman_get_device(struct resource *r); rman_res_t
rman_get_size(struct resource *r); u_int
rman_get_flags(struct resource *r); void
rman_set_mapping(struct resource *r, struct resource_map *map); void
rman_get_mapping(struct resource *r, struct resource_map *map); void
rman_set_virtual(struct resource *r, void *v); void *
rman_get_virtual(struct resource *r); void
rman_set_bustag(struct resource *r, bus_space_tag_t t); bus_space_tag_t
rman_get_bustag(struct resource *r); void
rman_set_bushandle(struct resource *r, bus_space_handle_t h); bus_space_handle_t
rman_get_bushandle(struct resource *r); void
rman_set_rid(struct resource *r, int rid); int
rman_get_rid(struct resource *r);
DESCRIPTION
The rman set of functions provides a flexible resource management abstraction. It is used extensively by the bus management code. It implements the abstractions of region and resource. A region descriptor is used to manage a region; this could be memory or some other form of bus space. Each region has a set of bounds. Within these bounds, allocated segments may reside. Each segment, termed a resource, has several properties which are represented by a 16-bit flag register, as follows.#define RF_ALLOCATED 0x0001 /* resource has been reserved */ #define RF_ACTIVE 0x0002 /* resource allocation has been activated */ #define RF_SHAREABLE 0x0004 /* resource permits contemporaneous sharing */ #define RF_FIRSTSHARE 0x0020 /* first in sharing list */ #define RF_PREFETCHABLE 0x0040 /* resource is prefetchable */ #define RF_UNMAPPED 0x0100 /* don't map resource when activating */
RMAN_ARRAY. The field
rm_descr shall be set to a string that
describes the resource to be managed. The
rm_start and
rm_end fields may be set to limit the range
of acceptable resource addresses. If these fields are not set,
rman_init() will initialize them to allow the
entire range of resource addresses. It also initializes any mutexes associated
with the structure. If rman_init() fails to
initialize the mutex, it will return
ENOMEM;
otherwise it will return 0 and
rm will be initialized.
The rman_fini() function frees any structures
associated with the structure pointed to by the
rm argument. If any of the resources within
the managed region have the RF_ALLOCATED
flag set, it will return EBUSY; otherwise,
any mutexes associated with the structure will be released and destroyed, and
the function will return 0.
The rman_manage_region() function establishes the
concept of a region which is under rman control.
The rman argument points to the region
descriptor. The start and
end arguments specify the bounds of the
region. If successful, rman_manage_region() will
return 0. If the region overlaps with an existing region, it will return
EBUSY. If any part of the region falls
outside of the valid address range for rm, it
will return EINVAL.
ENOMEM will be returned when
rman_manage_region() failed to allocate memory
for the region.
The rman_init_from_resource() function is a wrapper
routine to create a resource manager backed by an existing resource. It
initializes rm using
rman_init() and then adds a region to
rm corresponding to the address range
allocated to r via
rman_manage_region().
The rman_first_free_region() and
rman_last_free_region() functions can be used to
query a resource manager for its first (or last) unallocated region. If
rm contains no free region, these functions
will return ENOENT. Otherwise,
*start and
*end are set to the bounds of the free region
and zero is returned.
The rman_reserve_resource_bound() function is where
the bulk of the rman logic is located. It
attempts to reserve a contiguous range in the specified region
rm for the use of the device
dev. The caller can specify the
start and
end of an acceptable range, as well as a
boundary restriction and required aligment, and the code will attempt to find
a free segment which fits. The start argument
is the lowest acceptable starting value of the resource. The
end argument is the highest acceptable ending
value of the resource. Therefore, start
+ count
- 1 must be ≤
end for any allocation to happen. The
aligment requirement (if any) is specified in
flags. The
bound argument may be set to specify a
boundary restriction such that an allocated region may cross an address that
is a multiple of the boundary. The bound
argument must be a power of two. It may be set to zero to specify no boundary
restriction. A shared segment will be allocated if the
RF_SHAREABLE flag is set, otherwise an
exclusive segment will be allocated. If this shared segment already exists,
the caller has its device added to the list of consumers.
The rman_reserve_resource() function is used to
reserve resources within a previously established region. It is a simplified
interface to rman_reserve_resource_bound() which
passes 0 for the bound argument.
The rman_make_alignment_flags() function returns
the flag mask corresponding to the desired alignment
size. This should be used when calling
rman_reserve_resource_bound().
The rman_is_region_manager() function returns true
if the allocated resource r was allocated
from rm. Otherwise, it returns false.
The rman_adjust_resource() function is used to
adjust the reserved address range of an allocated resource to reserve
start through
end. It can be used to grow or shrink one or
both ends of the resource range. The current implementation does not support
entirely relocating the resource and will fail with
EINVAL if the new resource range does not
overlap the old resource range. If either end of the resource range grows and
the new resource range would conflict with another allocated resource, the
function will fail with EBUSY. The
rman_adjust_resource() function does not support
adjusting the resource range for shared resources and will fail such attempts
with EINVAL. Upon success, the resource
r will have a start address of
start and an end address of
end and the function will return zero. Note
that none of the constraints of the original allocation request such as
alignment or boundary restrictions are checked by
rman_adjust_resource(). It is the caller's
responsibility to enforce any such requirements.
The rman_release_resource() function releases the
reserved resource r. It may attempt to merge
adjacent free resources.
The rman_activate_resource() function marks a
resource as active, by setting the
RF_ACTIVE flag. If this is a time shared
resource, and the caller has not yet acquired the resource, the function
returns EBUSY.
The rman_deactivate_resource() function marks a
resource r as inactive, by clearing the
RF_ACTIVE flag. If other consumers are
waiting for this range, it will wakeup their threads.
The rman_get_start(),
rman_get_end(),
rman_get_size(), and
rman_get_flags() functions return the bounds,
size and flags of the previously reserved resource
r.
The rman_set_bustag() function associates a
bus_space_tag_t
t with the resource
r. The
rman_get_bustag() function is used to retrieve
this tag once set.
The rman_set_bushandle() function associates a
bus_space_handle_t
h with the resource
r. The
rman_get_bushandle() function is used to retrieve
this handle once set.
The rman_set_virtual() function is used to
associate a kernel virtual address with a resource
r. The
rman_get_virtual() function can be used to
retrieve the KVA once set.
The rman_set_mapping() function is used to
associate a resource mapping with a resource
r. The mapping must cover the entire
resource. Setting a mapping sets the associated
bus_space(9) handle and tag for
r as well as the kernel virtual address if
the mapping contains one. These individual values can be retrieved via
rman_get_bushandle(),
rman_get_bustag(), and
rman_get_virtual().
The rman_get_mapping() function can be used to
retrieve the associated resource mapping once set.
The rman_set_rid() function associates a resource
identifier with a resource r. The
rman_get_rid() function retrieves this RID.
The rman_get_device() function returns a pointer to
the device which reserved the resource r.
SEE ALSO
bus_activate_resource(9), bus_adjust_resource(9), bus_alloc_resource(9), bus_map_resource(9), bus_release_resource(9), bus_set_resource(9), bus_space(9), mutex(9)AUTHORS
This manual page was written by Bruce M Simpson <[email protected]>.| May 20, 2016 | Debian |