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VM_MAP_FINDSPACE(9) Kernel Developer's Manual VM_MAP_FINDSPACE(9)

NAME

vm_map_findspace —
find a free region within a map

SYNOPSIS

#include <sys/param.h>
#include <vm/vm.h>
#include <vm/vm_map.h>

int
vm_map_findspace(vm_map_t map, vm_offset_t start, vm_size_t length, vm_offset_t *addr);

DESCRIPTION

The vm_map_findspace() function attempts to find a region with sufficient space in the map for an object of size length at the address addr.

IMPLEMENTATION NOTES

It is the caller's responsibility to obtain a lock on the map using vm_map_lock(9) before calling this function.

This routine may call pmap_growkernel(9) to grow the kernel's address space, if and only if the mapping is being made within the kernel address space, and if insufficient space remains in the kernel_map.

RETURN VALUES

The vm_map_findspace() function returns the value 0 if successful, and *addr will contain the first virtual address in the found region; otherwise, the value 1 is returned.

SEE ALSO

pmap_growkernel(9), vm_map(9), vm_map_entry_resize_free(9), vm_map_lock(9)

AUTHORS

This manual page was written by Bruce M Simpson <bms@spc.org>.
July 19, 2003 Linux 4.19.0-10-amd64