//! Custom nonstandard syscalls
use rcore_memory::memory_set::handler::Linear;
use rcore_memory::memory_set::MemoryAttr;
use super::*;

/// Allocate this PCI device to user space
/// The kernel driver using the PCI device will be unloaded
#[cfg(target_arch = "x86_64")]
pub fn sys_map_pci_device(vendor: usize, product: usize) -> SysResult {
    use crate::drivers::bus::pci;
    info!(
        "map_pci_device: vendor: {:x}, product: {:x}",
        vendor, product
    );

    let tag = pci::find_device(vendor as u32, product as u32)
        .ok_or(SysError::ENOENT)?;
    if pci::detach_driver(&tag) {
        info!("Kernel driver detached");
    }

    // Get BAR0 memory
    let (base, len) = unsafe { tag.get_bar_mem(0) }
        .ok_or(SysError::ENOENT)?;

    let mut proc = process();
    let virt_addr = proc.vm.find_free_area(0, len);
    let attr = MemoryAttr::default().user();
    proc.vm.push(
        virt_addr,
        virt_addr + len,
        attr,
        Linear::new(base as isize - virt_addr as isize),
        "pci",
    );
    Ok(virt_addr)
}

#[cfg(not(target_arch = "x86_64"))]
pub fn sys_map_pci_device(vendor: usize, product: usize) -> SysResult {
    Err(SysError::ENOSYS)
}

/// Get start physical addresses of frames
/// mapped to a list of virtual addresses.
pub fn sys_get_paddr(vaddrs: *const u64, paddrs: *mut u64, count: usize) -> SysResult {
    let mut proc = process();
    proc.vm.check_read_array(vaddrs, count)?;
    proc.vm.check_write_array(paddrs, count)?;
    let vaddrs = unsafe { slice::from_raw_parts(vaddrs, count) };
    let paddrs = unsafe { slice::from_raw_parts_mut(paddrs, count) };
    for i in 0..count {
        let paddr = proc.vm.translate(vaddrs[i] as usize).unwrap_or(0);
        paddrs[i] = paddr as u64;
    }
    Ok(0)
}