Add statvfs

Makefile

@@ -425,6 +425,7 @@ coreutils: \
 	filesystem/bin/cut \
 	filesystem/bin/date \
 	filesystem/bin/dd \
+	filesystem/bin/df \
 	filesystem/bin/du \
 	filesystem/bin/echo \
 	filesystem/bin/env \

kernel/scheme/user.rs

@@ -11,7 +11,7 @@ use context::{self, Context};
 use context::memory::Grant;
 use scheme::{AtomicSchemeId, ATOMIC_SCHEMEID_INIT, SchemeId};
 use sync::{WaitQueue, WaitMap};
-use syscall::data::{Packet, Stat};
+use syscall::data::{Packet, Stat, StatVfs};
 use syscall::error::*;
 use syscall::flag::{EVENT_READ, O_NONBLOCK};
 use syscall::number::*;
@@ -332,7 +332,15 @@ impl Scheme for UserScheme {
     fn fstat(&self, file: usize, stat: &mut Stat) -> Result<usize> {
         let inner = self.inner.upgrade().ok_or(Error::new(ENODEV))?;
         let address = inner.capture_mut(stat)?;
-        let result = inner.call(SYS_FSTAT, file, address, 0);
+        let result = inner.call(SYS_FSTAT, file, address, mem::size_of::<Stat>());
+        let _ = inner.release(address);
+        result
+    }
+
+    fn fstatvfs(&self, file: usize, stat: &mut StatVfs) -> Result<usize> {
+        let inner = self.inner.upgrade().ok_or(Error::new(ENODEV))?;
+        let address = inner.capture_mut(stat)?;
+        let result = inner.call(SYS_FSTATVFS, file, address, mem::size_of::<StatVfs>());
         let _ = inner.release(address);
         result
     }

programs/coreutils

@@ -1 +1 @@
-Subproject commit 4b58de0b3c66634f95668e47466014138c5f71bd
+Subproject commit 3308c4507cfe7c3922e41ad472d792dac864e83f

programs/extrautils

@@ -1 +1 @@
-Subproject commit 1d0e93bb3c35ef58cd1ad8039b30701033ff2e98
+Subproject commit b3d8bf61860cd4c7c2263b2798779aa182cab1d6

programs/netutils

@@ -1 +1 @@
-Subproject commit fca407875c4184d17105fe2d455d0f1e85f80a05
+Subproject commit 2ce04b5f82a04f9d88ed8664dde18fc2468a046f

schemes/redoxfs

@@ -1 +1 @@
-Subproject commit 31605167ceb20bc3e2ffb6ef0b15fc05ca16ad7c
+Subproject commit dcaf5c76be265bbfa5013cf131f14fa79680a634

syscall

@@ -1 +1 @@
-Subproject commit 8ce29a6ea29042d4101733cc25e84a013a74018a
+Subproject commit cc90408d147cc1d23b0e820d5b47522bd7dfc847