Merge #876

876: add mlockall and munlockall r=asomers a=afck

Closes #875 

1 files changed, 25 insertions, 0 deletions

diff --git a/src/sys/mman.rs b/src/sys/mman.rs
index 9d1f88df..f2cc699b 100644
--- a/src/sys/mman.rs
+++ b/src/sys/mman.rs
@@ -205,14 +205,39 @@ libc_bitflags!{
     }
 }
 
+libc_bitflags!{
+    /// Flags for `mlockall`.
+    pub struct MlockAllFlags: c_int {
+        /// Lock pages that are currently mapped into the address space of the process.
+        MCL_CURRENT;
+        /// Lock pages which will become mapped into the address space of the process in the future.
+        MCL_FUTURE;
+    }
+}
+
+/// Locks all memory pages that contain part of the address range with `length` bytes starting at
+/// `addr`. Locked pages never move to the swap area.
 pub unsafe fn mlock(addr: *const c_void, length: size_t) -> Result<()> {
     Errno::result(libc::mlock(addr, length)).map(drop)
 }
 
+/// Unlocks all memory pages that contain part of the address range with `length` bytes starting at
+/// `addr`.
 pub unsafe fn munlock(addr: *const c_void, length: size_t) -> Result<()> {
     Errno::result(libc::munlock(addr, length)).map(drop)
 }
 
+/// Locks all memory pages mapped into this process' address space. Locked pages never move to the
+/// swap area.
+pub fn mlockall(flags: MlockAllFlags) -> Result<()> {
+    unsafe { Errno::result(libc::mlockall(flags.bits())) }.map(drop)
+}
+
+/// Unlocks all memory pages mapped into this process' address space.
+pub fn munlockall() -> Result<()> {
+    unsafe { Errno::result(libc::munlockall()) }.map(drop)
+}
+
 /// Calls to mmap are inherently unsafe, so they must be made in an unsafe block. Typically
 /// a higher-level abstraction will hide the unsafe interactions with the mmap'd region.
 pub unsafe fn mmap(addr: *mut c_void, length: size_t, prot: ProtFlags, flags: MapFlags, fd: RawFd, offset: off_t) -> Result<*mut c_void> {