| //! Global Allocator for UEFI. |
| //! Uses [r-efi-alloc](https://crates.io/crates/r-efi-alloc) |
| |
| use r_efi::protocols::loaded_image; |
| |
| use super::helpers; |
| use crate::alloc::{GlobalAlloc, Layout, System}; |
| use crate::sync::OnceLock; |
| |
| #[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) } |
| } |
| } |