bus_adjust_resource9freebsd
Adjust resource allocated from a parent bus
Usage
#include <sys/param.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <machine/resource.h>
int
bus_adjust_resource(device_t dev, int type, struct resource *r, rman_res_t start, rman_res_t end);
Overview
This function is used to ask the parent bus to adjust the resource range assigned to an allocated resource. The resource r should have been allocated by a previous call to bus_alloc_resource(9). The new resource range must overlap the existing range of r. The type argument should match the type argument passed to bus_alloc_resource(9) when the resource was initially allocated.
Note that none of the constraints of the original allocation request such as alignment or boundary restrictions are checked by bus_adjust_resource(). It is the caller's responsibility to enforce any such requirements.
Return values
The bus_adjust_resource() method returns zero on success or an error code on failure.
Examples
Grow an existing memory resource by 4096 bytes.
struct resource *res; int error; error = bus_adjust_resource(dev, SYS_RES_MEMORY, res, rman_get_start(res), rman_get_end(res) + 0x1000);
Errors
bus_adjust_resource() will fail if:
- [EINVAL]
-
The dev device does not have a parent device.
- [EINVAL]
-
The r resource is a shared resource.
- [EINVAL]
-
The new address range does not overlap with the existing address range of r.
- [EBUSY]
-
The new address range conflicts with another allocated resource.
Releases
6 releases since Debian 8 (Jessie); the text changed 3 times.