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REGION_INTERSECTS(9) Hardware Interfaces REGION_INTERSECTS(9)

NAME

region_intersects - determine intersection of region with known resources

SYNOPSIS

int region_intersects(resource_size_t start, size_t size, unsigned long flags, unsigned long desc);

ARGUMENTS

start
region start address

size

size of region

flags

flags of resource (in iomem_resource)

desc

descriptor of resource (in iomem_resource) or IORES_DESC_NONE

DESCRIPTION

Check if the specified region partially overlaps or fully eclipses a resource identified by flags and desc (optional with IORES_DESC_NONE). Return REGION_DISJOINT if the region does not overlap flags/desc, return REGION_MIXED if the region overlaps flags/desc and another resource, and return REGION_INTERSECTS if the region overlaps flags/desc and no other defined resource. Note that REGION_INTERSECTS is also returned in the case when the specified region overlaps RAM and undefined memory holes.

region_intersect is used by memory remapping functions to ensure the user is not remapping RAM and is a vast speed up over walking through the resource table page by page.

COPYRIGHT

April 2019 Kernel Hackers Manual 4.9.