How do I move a buffer into the data segment using gcc inline assembly?

I want to try to use the ide_read_sectors and ide_write_sectors from OsDev's PCI IDE driver implementation here, https://wiki.osdev.org/PCI_IDE_Controller#Read.2FWrite_From_ATA_Drive.

To move the buffer (a u8* buffer) into the data segment using

asm volatile("mov %0, %%CS"            : :"r"(buffer));

It crashed the program.

My overall code is based on this tutorial, https://github.com/cfenollosa/os-tutorial. To clarify, I want to move something like a string to cs.