feat(userspace): userspace support

build: updated CMakeLists to build and copy to initramfs

wip(syscalls): initial syscalls

chore(ksh/kfetch): minor changes

chore(gitignore): added initramfs/*

kernel/inc/arch/x86_64/cpuinfo.h

@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 // Copyright (c) 2026 0xKarinyash
-
+#pragma once
 #include <types.h>
 
 #define CPU_FEAT_FPU      (1ULL << 0)
@@ -24,7 +24,11 @@
 #define CPU_FEAT_HYPERVISOR (1ULL << 30) 
 
 typedef struct {
-    i32 features;
+    u64 user_rsp;
+    u64 kernel_rsp;
+    u64 self;
+
+    u64 features;
     char vendor[13];
     u32 family;
     u32 model;
@@ -32,5 +36,5 @@ typedef struct {
 
 extern cpu_info g_cpu;
 
-void cpuinfo_init();
+void cpuinfo_init(u64 kernel_stack_top);
 bool cpu_has(u64 feature);

kernel/inc/arch/x86_64/syscall.h

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Copyright (c) 2026 0xKarinyash
+
+#pragma once
+
+#define MSR_EFER         0xC0000080
+#define MSR_STAR         0xC0000081
+#define MSR_LSTAR        0xC0000082
+#define MSR_FMASK        0xC0000084
+#define MSR_KERNEL_GS_BASE 0xC0000102
+
+#define EFER_SCE         0x01 // System Call Enable
+
+typedef enum {
+    SYS_EXIT,
+    SYS_EXEC,
+    SYS_WRITE,
+} syscalls;
+
+void syscall_init();

kernel/inc/core/loader.h

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Copyright (c) 2026 0xKarinyash
+
+#pragma once
+
+#include <types.h>
+
+bool exec_init(const char* path);
+void init_task_entry();

kernel/inc/core/userspace.h

@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+// Copyright (c) 2026 0xKarinyash
+
+#pragma once
+
+void jump_to_userspace(void* entry, void* user_stack_top);

kernel/inc/drivers/shitgui.h

@@ -26,16 +26,8 @@ typedef struct {
     const unsigned char* base;
 } SG_Font;
 
-typedef struct {
-    SG_Context *ctx;
-    SG_Point pos;
-    const char *title;
-} SG_Window;
-
 void sg_init(SG_Context *ctx);
 u32 sg_get_pixel(SG_Context *ctx, SG_Point *p);
 void sg_put_img(SG_Context *ctx, SG_Point *p, SG_Image *img);
 void sg_draw_rect(SG_Context *ctx, SG_Point *p, u32 w, u32 h, u32 color);
-void sg_draw_char_bitmap(SG_Context *ctx, SG_Point *p, char c, u32 color, SG_Font *font);
-SG_Window* create_window(const char *title, SG_Point* size, SG_Point* position);
-void composer_task();
+void sg_draw_char_bitmap(SG_Context *ctx, SG_Point *p, char c, u32 color, SG_Font *font);