blob: ad3904d82f3ff3b9a7ede72c961331bc51076e43 [file] [log] [blame]
//! Global Allocator for UEFI.
//! Uses [r-efi-alloc](https://crates.io/crates/r-efi-alloc)
use r_efi::protocols::loaded_image;
use crate::alloc::{GlobalAlloc, Layout, System};
use crate::sync::OnceLock;
use crate::sys::uefi::helpers;
#[stable(feature = "alloc_system_type", since = "1.28.0")]
unsafe impl GlobalAlloc for System {
unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
static EFI_MEMORY_TYPE: OnceLock<u32> = OnceLock::new();
// Return null pointer if boot services are not available
if crate::os::uefi::env::boot_services().is_none() {
return crate::ptr::null_mut();
}
// If boot services is valid then SystemTable is not null.
let system_table = crate::os::uefi::env::system_table().as_ptr().cast();
// Each loaded image has an image handle that supports `EFI_LOADED_IMAGE_PROTOCOL`. Thus, this
// will never fail.
let mem_type = EFI_MEMORY_TYPE.get_or_init(|| {
let protocol = helpers::image_handle_protocol::<loaded_image::Protocol>(
loaded_image::PROTOCOL_GUID,
)
.unwrap();
// Gives allocations the memory type that the data sections were loaded as.
unsafe { (*protocol.as_ptr()).image_data_type }
});
// The caller must ensure non-0 layout
unsafe { r_efi_alloc::raw::alloc(system_table, layout, *mem_type) }
}
unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
// Do nothing if boot services are not available
if crate::os::uefi::env::boot_services().is_none() {
return;
}
// If boot services is valid then SystemTable is not null.
let system_table = crate::os::uefi::env::system_table().as_ptr().cast();
// The caller must ensure non-0 layout
unsafe { r_efi_alloc::raw::dealloc(system_table, ptr, layout) }
}
}