Add support for ext2 filesystem

include/sys/mount.h

@@ -34,7 +34,7 @@ typedef struct vfsconf vfsconf_t;
 typedef struct statvfs statvfs_t;
 
 /* VFS operations */
-typedef int vfs_mount_t(mount_t *m);
+typedef int vfs_mount_t(mount_t *m, vnode_t *vsrc);
 typedef int vfs_root_t(mount_t *m, vnode_t **vp);
 typedef int vfs_statvfs_t(mount_t *m, statvfs_t *sb);
 typedef int vfs_vget_t(mount_t *m, ino_t ino, vnode_t **vp);
@@ -78,8 +78,8 @@ typedef struct mount {
   void *mnt_data; /* Filesystem-specific arbitrary data */
 } mount_t;
 
-static inline int VFS_MOUNT(mount_t *m) {
-  return m->mnt_vfsops->vfs_mount(m);
+static inline int VFS_MOUNT(mount_t *m, vnode_t *vsrc) {
+  return m->mnt_vfsops->vfs_mount(m, vsrc);
 }
 
 static inline int VFS_ROOT(mount_t *m, vnode_t **vp) {
@@ -105,9 +105,10 @@ vfsconf_t *vfs_get_by_name(const char *name);
  * list. */
 mount_t *vfs_mount_alloc(vnode_t *v, vfsconf_t *vfc);
 
-/* Mount a new instance of the filesystem vfc at the vnode v. Does not support
- * remounting. TODO: Additional filesystem-specific arguments. */
-int vfs_domount(vfsconf_t *vfc, vnode_t *v);
+/* Mount a new instance of the filesystem vfc at the vnode vdst. Does not
+ * support remounting. Use vsrc as a source for fs data if not NULL.
+ *TODO: Additional filesystem-specific arguments. */
+int vfs_domount(vfsconf_t *vfc, vnode_t *vdst, vnode_t *vsrc);
 
 #else /* !_KERNEL */
 #include <sys/cdefs.h>

include/sys/syscallargs.h

@@ -78,6 +78,7 @@ typedef struct {
 } mmap_args_t;
 
 typedef struct {
+  SYSCALLARG(const char *) source;
   SYSCALLARG(const char *) type;
   SYSCALLARG(const char *) path;
 } mount_args_t;

include/sys/vfs.h

@@ -105,7 +105,7 @@ int do_futimens(proc_t *p, int fd, timespec_t *times);
 int do_utimensat(proc_t *p, int fd, char *path, timespec_t *times, int flag);
 
 /* Mount a new instance of the filesystem named fs at the requested path. */
-int do_mount(proc_t *p, const char *fs, const char *path);
+int do_mount(proc_t *p, const char *source, const char *fs, const char *path);
 int do_getdents(proc_t *p, int fd, uio_t *uio);
 int do_statvfs(proc_t *p, char *path, statvfs_t *buf);
 int do_fstatvfs(proc_t *p, int fd, statvfs_t *buf);

sys/kern/devfs.c

@@ -345,7 +345,7 @@ static vnodeops_t devfs_dir_vnodeops = {
 
 /* We are using a single vnode for each devfs_node
  * instead of allocating a new one each time, to simplify things. */
-static int devfs_mount(mount_t *m) {
+static int devfs_mount(mount_t *m, vnode_t *vsrc) {
   devfs.root->dn_vnode->v_mount = m;
   m->mnt_data = &devfs;
   return 0;