fsread
ssize_t (*fsread)(boot2_ino_t, void *, size_t);
.fsread = boot2_ufs_read
return fsread(0, NULL, 0);
read = fsread(ino, buf, size);
if ((size_t)fsapi->fsread(inode, buf, nbyte) != nbyte) {
fsapi->fsread(ino, cmd, sizeof(cmd));
.fsread = boot2_hammer_read
.fsread = boot2_hammer2_read