vslock
, vsunlock
— lock/unlock user space addresses in
memory
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.
The vslock
() function will return 0 on
success, otherwise it will return one of the errors listed below.
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.