diff --git a/tasks/libl4/include/l4lib/ipcdefs.h b/tasks/libl4/include/l4lib/ipcdefs.h
index 4fb33ac..4bb51fd 100644
--- a/tasks/libl4/include/l4lib/ipcdefs.h
+++ b/tasks/libl4/include/l4lib/ipcdefs.h
@@ -50,7 +50,6 @@
 #define L4_IPC_TAG_EXIT			27
 #define L4_IPC_TAG_WAIT			28
 
-
 /* Tags for ipc between fs0 and mm0 */
 #define L4_IPC_TAG_TASKDATA		40
 #define L4_IPC_TAG_PAGER_OPEN		41	/* vfs sends the pager open file data. */
diff --git a/tasks/mm0/include/syscalls.h b/tasks/mm0/include/syscalls.h
index 6d17e06..7d210c2 100644
--- a/tasks/mm0/include/syscalls.h
+++ b/tasks/mm0/include/syscalls.h
@@ -27,6 +27,7 @@ void *sys_mmap(struct tcb *sender, void *start, size_t length, int prot,
 	       int flags, int fd, off_t offset);
 
 int sys_munmap(struct tcb *sender, void *vaddr, unsigned long size);
+int sys_msync(struct tcb *task, void *start, unsigned long length, int flags);
 
 struct sys_shmat_args {
 	l4id_t shmid;
diff --git a/tasks/mm0/main.c b/tasks/mm0/main.c
index 899d7eb..dd6a32d 100644
--- a/tasks/mm0/main.c
+++ b/tasks/mm0/main.c
@@ -121,6 +121,15 @@ void handle_requests(void)
 			 args->flags, args->fd, __pfn(args->offset));
 		break;
 	}
+	case L4_IPC_TAG_MUNMAP: {
+		ret = sys_munmap(sender, (void *)mr[0], (unsigned long)mr[1]);
+		break;
+	}
+	case L4_IPC_TAG_MSYNC: {
+		ret = sys_msync(sender, (void *)mr[0],
+				(unsigned long)mr[1], (int)mr[2]);
+		break;
+	}
 	case L4_IPC_TAG_FORK: {
 		ret = sys_fork(sender);
 		break;
@@ -134,16 +143,6 @@ void handle_requests(void)
 //		ret = sys_brk(sender, (void *)mr[0]);
 //		break;
 	}
-
-	case L4_IPC_TAG_MUNMAP: {
-		ret = sys_munmap(sender, (void *)mr[0], (unsigned long)mr[1]);
-		break;
-	}
-	case L4_IPC_TAG_MSYNC: {
-		/* TODO: Use arg struct instead */
-//		sys_msync(sender, (void *)mr[0], (int)mr[1], (int)mr[2]);
-		break;
-	}
 	default:
 		printf("%s: Unrecognised ipc tag (%d) "
 		       "received from (%d). Full mr reading: "
diff --git a/tasks/mm0/src/munmap.c b/tasks/mm0/src/munmap.c
index d3e84d0..7f44fa6 100644
--- a/tasks/mm0/src/munmap.c
+++ b/tasks/mm0/src/munmap.c
@@ -8,11 +8,6 @@
 #include <l4/api/errno.h>
 #include <l4lib/arch/syslib.h>
 
-/* TODO: This is to be implemented when fs0 is ready. */
-int do_msync(void *addr, unsigned long size, unsigned int flags, struct tcb *task)
-{
-	return 0;
-}
 
 /* This splits a vma, splitter region must be in the *middle* of original vma */
 int vma_split(struct vm_area *vma, struct tcb *task,
@@ -142,7 +137,7 @@ int do_munmap(struct tcb *task, void *vaddr, unsigned long npages)
 		if ((err = vma_flush_pages(vma)) < 0)
 			return err;
 
-		/* Unmap the vma accordingly */
+		/* Unmap the vma accordingly. Note, this may delete the vma */
 		if ((err = vma_unmap(vma, task, munmap_start,
 				     munmap_end)) < 0)
 			return err;
@@ -165,3 +160,35 @@ int sys_munmap(struct tcb *task, void *start, unsigned long length)
 }
 
 
+/* Syncs mapped area. Currently just synchronously */
+int do_msync(struct tcb *task, void *vaddr, unsigned long npages, int flags)
+{
+	const unsigned long msync_start = __pfn(vaddr);
+	const unsigned long msync_end = msync_start + npages;
+	struct vm_area *vma;
+	int err;
+
+	/* Find a vma that overlaps with this address range */
+	while ((vma = find_vma_byrange(msync_start, msync_end,
+				       &task->vm_area_head->list))) {
+
+		/* Flush pages if vma is writable, dirty and file-backed. */
+		if ((err = vma_flush_pages(vma)) < 0)
+			return err;
+	}
+	return 0;
+}
+
+int sys_msync(struct tcb *task, void *start, unsigned long length, int flags)
+{
+	/* Must be aligned on a page boundary */
+	if ((unsigned long)start & PAGE_MASK)
+		return -EINVAL;
+
+	/*
+	 * TODO: We need to pass sync'ed and non-sync'ed file flushes to vfs
+	 * and support synced and non-synced io.
+	 */
+	return do_msync(task, start, __pfn(page_align_up(length)), flags);
+}
+