Index: uspace/lib/c/include/ipc/vfs.h
===================================================================
--- uspace/lib/c/include/ipc/vfs.h	(revision 7329e6a6a987bc53fac8c85bd8647e952ae7fb9c)
+++ uspace/lib/c/include/ipc/vfs.h	(revision 5581b46972ec913d0356783e55d0989fa3372729)
@@ -36,6 +36,7 @@
 #define LIBC_IPC_VFS_H_
 
+#include <ipc/ipc.h>
 #include <sys/types.h>
-#include <ipc/ipc.h>
+#include <bool.h>
 
 #define FS_NAME_MAXLEN  20
@@ -55,4 +56,6 @@
 	/** Unique identifier of the fs. */
 	char name[FS_NAME_MAXLEN + 1];
+	bool concurrent_read_write;
+	bool write_retains_size;
 } vfs_info_t;
 
Index: uspace/srv/fs/devfs/devfs.c
===================================================================
--- uspace/srv/fs/devfs/devfs.c	(revision 7329e6a6a987bc53fac8c85bd8647e952ae7fb9c)
+++ uspace/srv/fs/devfs/devfs.c	(revision 5581b46972ec913d0356783e55d0989fa3372729)
@@ -53,4 +53,6 @@
 static vfs_info_t devfs_vfs_info = {
 	.name = NAME,
+	.concurrent_read_write = false,
+	.write_retains_size = false,
 };
 
Index: uspace/srv/fs/fat/fat.c
===================================================================
--- uspace/srv/fs/fat/fat.c	(revision 7329e6a6a987bc53fac8c85bd8647e952ae7fb9c)
+++ uspace/srv/fs/fat/fat.c	(revision 5581b46972ec913d0356783e55d0989fa3372729)
@@ -52,4 +52,6 @@
 vfs_info_t fat_vfs_info = {
 	.name = NAME,
+	.concurrent_read_write = false,
+	.write_retains_size = false,	
 };
 
Index: uspace/srv/fs/tmpfs/tmpfs.c
===================================================================
--- uspace/srv/fs/tmpfs/tmpfs.c	(revision 7329e6a6a987bc53fac8c85bd8647e952ae7fb9c)
+++ uspace/srv/fs/tmpfs/tmpfs.c	(revision 5581b46972ec913d0356783e55d0989fa3372729)
@@ -57,4 +57,6 @@
 vfs_info_t tmpfs_vfs_info = {
 	.name = NAME,
+	.concurrent_read_write = false,
+	.write_retains_size = false,
 };