add userland target

Author: 0x6D70

build/linker-scripts/userland.ld

@@ -0,0 +1,51 @@
+/* Tell the linker that we want an x86_64 ELF64 output file */
+OUTPUT_FORMAT(elf64-x86-64)
+OUTPUT_ARCH(i386:x86-64)
+
+/* We want the symbol `_start` to be our entry point */
+ENTRY(_start)
+
+/* Define the program headers we want so the bootloader gives us the right */
+/* MMU permissions */
+PHDRS
+{
+    null    PT_NULL    FLAGS(0) ;                   /* Null segment */
+    text    PT_LOAD    FLAGS((1 << 0) | (1 << 2)) ; /* Execute + Read */
+    rodata  PT_LOAD    FLAGS((1 << 2)) ;            /* Read only */
+    data    PT_LOAD    FLAGS((1 << 1) | (1 << 2)) ; /* Write + Read */
+}
+
+SECTIONS
+{
+    . = 0x40000;
+
+    .text : {
+        *(.text .text.*)
+    } :text
+
+    /* Move to the next memory page for .rodata */
+    . += CONSTANT(MAXPAGESIZE);
+
+    .rodata : {
+        *(.rodata .rodata.*)
+    } :rodata
+
+    /* Move to the next memory page for .data */
+    . += CONSTANT(MAXPAGESIZE);
+
+    .data : {
+        *(.data .data.*)
+    } :data
+
+    .bss : {
+        *(COMMON)
+        *(.bss .bss.*)
+    } :data
+
+    .got : {
+        *(.got)
+    } :data
+
+    . += CONSTANT(MAXPAGESIZE);
+
+}

build/targets/x86_64-userland.json

@@ -0,0 +1,23 @@
+{
+  "llvm-target": "x86_64-unknown-none",
+  "data-layout": "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128",
+  "arch": "x86_64",
+  "target-endian": "little",
+  "target-pointer-width": 64,
+  "target-c-int-width": 32,
+  "os": "none",
+  "executables": true,
+  "linker-flavor": "ld.lld",
+  "linker": "rust-lld",
+  "disable-redzone": true,
+  "panic-strategy": "abort",
+  "features": "-mmx,-sse,+soft-float",
+  "rustc-abi": "x86-softfloat",
+  "code-model": "small",
+  "pre-link-args": {
+    "ld.lld": [
+      "--gc-sections",
+      "--script=./build/linker-scripts/userland.ld"
+    ]
+  }
+}

build/xtask/src/main.rs

@@ -128,7 +128,7 @@ fn build(sh: &Shell, rl: bool, mut args: Arguments) -> Result<()> {
         "cargo build
                 {release...}
                 -p init
-                --target ./build/targets/{target}.json
+                --target ./build/targets/{target}-userland.json
                 -Z build-std=core,alloc,compiler_builtins
                 -Z build-std-features=compiler-builtins-mem"
     )
@@ -138,7 +138,7 @@ fn build(sh: &Shell, rl: bool, mut args: Arguments) -> Result<()> {
 
     cmd!(
         sh,
-        "cp {xernel_dir}/target/x86_64/{build_dir}/init {xernel_dir}/target/"
+        "cp {xernel_dir}/target/x86_64-userland/{build_dir}/init {xernel_dir}/target/"
     )
     .run()?;