NAME¶
vslock,
vsunlock —
lock/unlock user space addresses in memory
SYNOPSIS¶
#include
<sys/param.h>
#include
<sys/proc.h>
#include
<vm/vm.h>
#include
<vm/vm_extern.h>
int
vslock(
void
*addr,
size_t
len);
void
vsunlock(
void
*addr,
size_t
len);
DESCRIPTION¶
The
vslock() and
vsunlock() functions respectively lock and
unlock a range of addresses belonging to the currently running process into
memory. The actual amount of memory locked is a multiple of the machine's page
size. The starting page number is computed by truncating
addr to the nearest preceding page boundary,
and by rounding up
addr +
len to the next page boundary. The process
context to use for this operation is taken from the global variable
curproc.
RETURN VALUES¶
The
vslock() function will return 0 on
success, otherwise it will return one of the errors listed below.
ERRORS¶
The
vslock() function will fail if:
- [
EINVAL]
- The addr and
len parameters specify a memory range
that wraps around the end of the machine address space.
- [
ENOMEM]
- The size of the specified address range exceeds the system limit on locked
memory.
- [
EFAULT]
- Some portion of the indicated address range is not allocated. There was an
error faulting/mapping a page.
