mount/linuc: add basic docstrings to public methods

Author: lucab

src/mount/linux.rs

@@ -50,13 +50,18 @@ libc_bitflags!(
 
 libc_bitflags!(
     pub struct MntFlags: c_int {
+        /// Abort pending requests before attempting the unmount
         MNT_FORCE;
+        /// Perform a lazy unmount
         MNT_DETACH;
+        /// Mark the mount as expired
         MNT_EXPIRE;
+        /// Do not dereference unmount path target if it is a symbolic link
         UMOUNT_NOFOLLOW;
     }
 );
 
+/// Mount a filesystem.
 pub fn mount<
     P1: ?Sized + NixPath,
     P2: ?Sized + NixPath,
@@ -99,13 +104,15 @@ pub fn mount<
     Errno::result(res).map(drop)
 }
 
+/// Unmount the filesystem mounted at `target`.
 pub fn umount<P: ?Sized + NixPath>(target: &P) -> Result<()> {
     let res =
         target.with_nix_path(|cstr| unsafe { libc::umount(cstr.as_ptr()) })?;
 
     Errno::result(res).map(drop)
 }
 
+/// Unmount the filesystem mounted at `target`, using `flags` to control the behavior of the operation.
 pub fn umount2<P: ?Sized + NixPath>(target: &P, flags: MntFlags) -> Result<()> {
     let res = target.with_nix_path(|cstr| unsafe {
         libc::umount2(cstr.as_ptr(), flags.bits)