Add EFI stuff to the metadata

flake.nix

@@ -34,7 +34,10 @@
         in
         {
           default = pkgs.mkShell {
-            packages = [ rust-uefi ];
+            packages = [
+              rust-uefi
+              pkgs.lldb
+            ];
 
             RUST_SRC_PATH = "${rust-uefi}/lib/rustlib/src/rust/library";
           };

src/abi.rs

@@ -2,8 +2,7 @@ extern crate alloc;
 use alloc::vec::Vec;
 use alloc::{collections::BTreeMap, string::String};
 use bitflags::bitflags;
-use uefi::prelude::BootServices;
+use uefi::table::boot::MemoryMap;
-use uefi::table::boot::MemoryType;
 use uefi::{
     proto::console::gop::{GraphicsOutput, PixelFormat},
     table::boot::PAGE_SIZE,
@@ -123,53 +122,33 @@ struct EFIMemoryMapHeader {
     descriptor_version: u32,
 }
 
-#[derive(Debug, Clone)]
+impl Serialize for MemoryMap {
-pub struct EFIMemoryMapParams {
+    fn alignment() -> usize {
-    header: EFIMemoryMapHeader,
+        4
-    map: Vec<u8>,
+    }
-}
 
-impl EFIMemoryMapParams {
+    fn size(&self) -> usize {
-    pub fn from_boot_services(bs: &BootServices) -> Self {
+        core::mem::size_of::<EFIMemoryMapHeader>() + self.as_raw().0.len()
-        let map = bs
+    }
-            .memory_map(MemoryType::LOADER_DATA)
-            .expect("Failed to get EFI memory map");
 
-        let (raw, meta) = map.as_raw();
+    fn serialize_raw(&self, out: &mut [u8]) {
+        let (raw, meta) = self.as_raw();
 
         let header = EFIMemoryMapHeader {
             memory_size: meta.map_size,
             descriptor_size: meta.desc_size,
             descriptor_version: meta.desc_version,
         };
-
+        let header_size = core::mem::size_of_val(&header);
-        Self {
-            header,
-            map: raw.to_vec(),
-        }
-    }
-}
-
-impl Serialize for EFIMemoryMapParams {
-    fn alignment() -> usize {
-        4
-    }
-
-    fn size(&self) -> usize {
-        core::mem::size_of::<EFIMemoryMapHeader>() + self.map.len()
-    }
-
-    fn serialize_raw(&self, out: &mut [u8]) {
-        let header_size = core::mem::size_of_val(&self.header);
         let header_bytes = unsafe {
             core::slice::from_raw_parts(
-                &self.header as *const EFIMemoryMapHeader as *const u8,
+                &header as *const EFIMemoryMapHeader as *const u8,
                 header_size,
             )
         };
 
         out[..header_size].copy_from_slice(header_bytes);
-        out[header_size..].copy_from_slice(&self.map);
+        out[header_size..].copy_from_slice(raw);
     }
 }
 
@@ -279,7 +258,6 @@ pub enum ModuleInfoType {
 }
 
 /// Value in the module info TLV
-#[derive(Clone)]
 pub enum ModuleInfoValue {
     StaticString(&'static str),
     String(String),
@@ -288,7 +266,7 @@ pub enum ModuleInfoValue {
     Buffer(Vec<u8>),
     Howto(Howto),
     EFIFrameBuffer(EFIFramebufferParams),
-    EFIMemoryMap(EFIMemoryMapParams),
+    EFIMemoryMap(MemoryMap),
 }
 
 impl ModuleInfoValue {
@@ -349,7 +327,7 @@ impl core::fmt::Debug for ModuleInfoValue {
 
 /// Key and value in the module info TLV
 /// TODO: figure out how to make this properly typesafe
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct ModuleInfoItem {
     pub tag: ModuleInfoType,
     pub value: ModuleInfoValue,

src/boot.rs

@@ -5,13 +5,25 @@ pub use x86_64::boot_kernel;
 mod x86_64 {
     use core::{arch::global_asm, slice};
 
-    use uefi::table::{boot::PAGE_SIZE, Boot, SystemTable};
+    use log::warn;
+    use uefi::{
+        prelude::BootServices,
+        proto::console::gop::GraphicsOutput,
+        table::{
+            boot::{MemoryType, PAGE_SIZE},
+            Boot, SystemTable,
+        },
+    };
     use x86_64::{
         structures::paging::{PageTable, PageTableFlags},
         PhysAddr,
     };
 
-    use crate::{object::Kernel, staging::allocate_code};
+    use crate::{
+        abi::{EFIFramebufferParams, ModuleInfoItem, ModuleInfoType, ModuleInfoValue, Serialize},
+        object::Kernel,
+        staging::allocate_code,
+    };
 
     global_asm!(
         r#"
@@ -67,6 +79,7 @@ trampoline_size:
         kernel_base: *const u8,
         modinfo_base: *const u8,
         free_ptr: *const u8,
+        staging: &mut [u8],
     ) {
         let misc_alloc = allocate_code(
             system_table.boot_services(),
@@ -113,6 +126,9 @@ trampoline_size:
         );
 
         unsafe {
+            // Serialize some final metadata. Calls exit boot services.
+            add_efi_metadata(system_table, staging);
+
             let trampoline_func: TrampolineFunction =
                 core::mem::transmute(misc_buf.trampoline.as_ptr());
             trampoline_func(
@@ -124,4 +140,50 @@ trampoline_size:
             );
         }
     }
+
+    unsafe fn add_efi_metadata(boot_system_table: SystemTable<Boot>, mut staging: &mut [u8]) {
+        staging = add_efi_framebuffer_metadata(boot_system_table.boot_services(), staging);
+
+        let (runtime_system_table, memory_map) =
+            boot_system_table.exit_boot_services(MemoryType::LOADER_DATA);
+        let memory_map_item = ModuleInfoItem {
+            tag: ModuleInfoType::EFIMemoryMap,
+            value: ModuleInfoValue::EFIMemoryMap(memory_map),
+        };
+        staging = memory_map_item.serialize_unaligned(staging);
+
+        let firmware_handle_item = ModuleInfoItem {
+            tag: ModuleInfoType::FirmwareHandle,
+            value: ModuleInfoValue::Pointer(runtime_system_table.as_ptr() as *const u8),
+        };
+        let _staging = firmware_handle_item.serialize_unaligned(staging);
+    }
+
+    fn add_efi_framebuffer_metadata<'a>(
+        boot_services: &BootServices,
+        staging: &'a mut [u8],
+    ) -> &'a mut [u8] {
+        let params = match parse_efi_framebuffer_params(boot_services) {
+            Ok(params) => params,
+            Err(err) => {
+                warn!("Unable to parse framebuffer parameters: {}", err);
+                return staging;
+            }
+        };
+
+        let item = ModuleInfoItem {
+            tag: ModuleInfoType::EFIFrameBuffer,
+            value: ModuleInfoValue::EFIFrameBuffer(params),
+        };
+
+        item.serialize_unaligned(staging)
+    }
+    fn parse_efi_framebuffer_params<'a>(
+        boot_services: &BootServices,
+    ) -> Result<EFIFramebufferParams, uefi::Error> {
+        let gop_handle = boot_services.get_handle_for_protocol::<GraphicsOutput>()?;
+        let mut gop = boot_services.open_protocol_exclusive::<GraphicsOutput>(gop_handle)?;
+        EFIFramebufferParams::from_graphics_output(&mut gop)
+            .ok_or_else(|| uefi::Error::new(uefi::Status::INVALID_PARAMETER, ()))
+    }
 }

src/main.rs

@@ -8,11 +8,11 @@ mod staging;
 
 extern crate alloc;
 
-use abi::{Environment, ModuleInfoItem, ModuleInfoType, ModuleInfoValue, Serialize};
+use abi::{Environment, Howto, ModuleInfoItem, ModuleInfoType, ModuleInfoValue, Serialize};
 use alloc::{collections::btree_map::BTreeMap, string::ToString};
 use log::info;
 use object::{Kernel, Module};
-use uefi::{fs::FileSystem, prelude::*};
+use uefi::{fs::FileSystem, prelude::*, proto::loaded_image::LoadedImage};
 
 #[entry]
 fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
@@ -20,6 +20,16 @@ fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
 
     info!("Starting freeloader");
 
+    {
+        let loaded_image_protocol = system_table
+            .boot_services()
+            .open_protocol_exclusive::<LoadedImage>(image_handle)
+            .expect("Failed to open LoadedImage protocol");
+        let (base, size) = loaded_image_protocol.info();
+        log::debug!("Image base: {:#x}, size: {:#x}", base as usize, size);
+        log::debug!("Main is at {:#x}", &main as *const _ as usize)
+    }
+
     let kernel_data = {
         let mut esp = FileSystem::new(
             system_table
@@ -42,12 +52,12 @@ fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
         "kernel".to_string(),
     )]));
 
-    // Allocate an extra 16KiB for items we have to add to metadata
+    // Allocate an extra 1 MiB for items we have to add to metadata, like memory map
     let metadata_size: usize = kernel_metadata
         .iter()
         .map(|item| item.alloc_size())
         .sum::<usize>()
-        + 16 * 1024;
+        + 1024 * 1024;
 
     let alloc_size = kernel.alloc_size() + environment.alloc_size() + metadata_size;
     let staging = staging::allocate_code(system_table.boot_services(), alloc_size);
@@ -61,7 +71,10 @@ fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
         value: ModuleInfoValue::Pointer(environ_base),
     });
 
-    let modinfo_base = next.as_ptr();
+    kernel_metadata.push(abi::ModuleInfoItem {
+        tag: ModuleInfoType::Howto,
+        value: ModuleInfoValue::Howto(Howto::VERBOSE | Howto::SERIAL),
+    });
 
     let free_ptr = unsafe { next.as_ptr().byte_add(metadata_size) };
     kernel_metadata.push(ModuleInfoItem {
@@ -69,11 +82,19 @@ fn main(image_handle: Handle, mut system_table: SystemTable<Boot>) -> Status {
         value: ModuleInfoValue::Pointer(free_ptr),
     });
 
+    let modinfo_base = next.as_ptr();
     for item in kernel_metadata.iter() {
         next = item.serialize_unaligned(next);
     }
 
-    boot::boot_kernel(system_table, kernel, kernel_base, modinfo_base, free_ptr);
+    boot::boot_kernel(
+        system_table,
+        kernel,
+        kernel_base,
+        modinfo_base,
+        free_ptr,
+        next,
+    );
 
     // boot_kernel shouldn't return
     Status::ABORTED

src/object.rs

@@ -91,7 +91,7 @@ impl<'a> Kernel<'a> {
                 .copy_from_slice(&self.elf[in_offset..in_offset + copy_size]);
 
             debug!(
-                "kernel: {:x}@{:x} -> {:x}",
+                "kernel: {:#x}@{:#x} -> {:#x}",
                 copy_size,
                 in_offset,
                 (&out[out_offset] as *const u8) as usize