vfs_readv         921 fs/nfsd/vfs.c  		host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset);
vfs_readv         650 fs/read_write.c 		ret = vfs_readv(file, vec, vlen, &pos);
vfs_readv        1363 include/linux/fs.h extern ssize_t vfs_readv(struct file *, const struct iovec __user *,