Setup TSS segment

src/boucane.cc

@@ -19,8 +19,33 @@ u64 kvar_terminus_psf_start;
 u64 kvar_terminus_psf_end;
 u64 kvar_logo_bmp_start;
 u64 kvar_logo_bmp_end;
+TSS kvar_tss;
 
 void (*printk)(char *str,...)=printf;
+extern u64 gdt64_tss;
+
+void configure_tss(){
+    u64 tss_addr=(u64)&kvar_tss;
+    u32 desc1=(tss_addr&0xFFFF)<<16|(sizeof(TSS)&0xFFFF);
+    tss_addr>>=16;
+    u32 desc2=(tss_addr&0xFF)|((tss_addr>>8)<<24);
+    tss_addr>>=16;
+    u32 desc3=tss_addr;
+
+    // Options
+    u32 options=0b1001; // 64-bits TSS type
+    options|=(0b1000<<4); // Present
+
+    // Configure GDT
+    u32 *gdt_entry=(u32*)&gdt64_tss;
+    gdt_entry[0]=desc1;
+    gdt_entry[1]=desc2|(options<<8);
+    gdt_entry[2]=desc3;
+    gdt_entry[3]=0;
+
+    // Configure segment
+    kvar_tss.rsp0=(u64)VIRT(kvar_stack_pma);
+}
 
 extern "C" void boucane(u64 mb_info){
     // Init linker variables
@@ -35,6 +60,7 @@ extern "C" void boucane(u64 mb_info){
     asm volatile ("movq $res_binary_res_logo_bmp_end, %0":"=m"(kvar_logo_bmp_end));
 
     // Init data structures
+    configure_tss();
     asm volatile ("call load_gdt");
     paging_enable();
     memtext_init();
@@ -74,5 +100,8 @@ extern "C" void boucane(u64 mb_info){
         mem/=1024;
         printk("RAM:%dMB\n", mem);
     }
+
+    printk("%x",&kvar_tss);
+    DUMP(&gdt64_tss);
     while(1);
 }

src/boucane.hpp

@@ -10,22 +10,42 @@
 #include "libs/stdio.hpp"
 #include "libs/string.hpp"
 
+// ---- Debug
+#define DUMP(var) asm volatile("push $0xABC; push %0; push $0xABC; _%=:; jmp _%="::"r"(var))
+#define DUMP2(var1,var2) asm volatile("push $0xABC; push %0; push %1; push $0xABC; _%=:; jmp _%="::"a"(var1),"b"(var2))
+
+// Functions
+extern void (*printk)(char *str,...);
+
+typedef struct {
+    u32 reserved;
+    u64 rsp0;
+    u64 rsp1;
+    u64 rsp2;
+    u64 reserved2;
+    u64 ist1;
+    u64 ist2;
+    u64 ist3;
+    u64 ist4;
+    u64 ist5;
+    u64 ist6;
+    u64 ist7;
+    u64 reserved3;
+    u16 reserved4;
+    u16 iomap_address;
+} __attribute__((packed)) TSS;
+
 /// @brief Various variables from the linker
 extern u64 kvar_kernel_vma;
 extern u64 kvar_stack_pma;
 extern u64 kvar_userspace_pma;
 extern u64 kvar_bss_start;
 extern u64 kvar_bss_end;
+extern TSS kvar_tss;
+
 
 /// @brief Binary references
 extern u64 kvar_terminus_psf_start;
 extern u64 kvar_terminus_psf_end;
 extern u64 kvar_logo_bmp_start;
-extern u64 kvar_logo_bmp_end;
-
-// ---- Debug
-#define DUMP(var) asm volatile("push $0xABC; push %0; push $0xABC; _%=:; jmp _%="::"r"(var))
-#define DUMP2(var1,var2) asm volatile("push $0xABC; push %0; push %1; push $0xABC; _%=:; jmp _%="::"a"(var1),"b"(var2))
-
-
-extern void (*printk)(char *str,...);
+extern u64 kvar_logo_bmp_end;

src/core/asm.hpp

@@ -21,3 +21,6 @@
 
 #define inb(port,dst) \
     asm volatile ("inb %%dx, %%al": "=a" (dst) : "d" (port))
+
+#define lpml4(pml4) \
+    asm volatile ("mov %0, %%rax; mov %%rax, %%cr3":: "r" (pml4))

src/core/gdt.S

@@ -1,4 +1,5 @@
 .code64
+.global gdt64_tss
 
 gdt64:
     gdt64_null:
@@ -15,6 +16,22 @@ gdt64:
     .byte 0
     .byte 0b10010010
     .word 0
+    gdt64_cs_user:
+    .long 0
+    .byte 0
+    .byte 0b11111100
+    .byte 0b00100000
+    .byte 0
+    gdt64_ds_user:
+    .long 0
+    .byte 0
+    .byte 0b11110010
+    .word 0
+    gdt64_tss:
+    .long 0
+    .long 0
+    .long 0
+    .long 0
 gdtr:
     .word . - gdt64 - 1
     .quad gdt64

src/core/paging.cc

@@ -1,4 +1,5 @@
 #include "paging.hpp"
+#include "core/asm.hpp"
 #include "core/types.hpp"
 #include "libs/stdio.hpp"
 #include "libs/string.hpp"
@@ -47,10 +48,7 @@ void paging_enable() {
     
     // Load new pml4
     u64 kpage_phy=((u64)kpages[0]-kvar_kernel_vma);
-    asm volatile(
-        "mov %0, %%rax        \n\t"
-        "mov %%rax, %%cr3     \n\t"
-        :: "r" (kpage_phy));
+    lpml4(kpage_phy);
 }
 
 u64* paging_allocate_contiguous(int npages){
@@ -187,6 +185,13 @@ void paging_allocate_addr(u64* pml4_table, u64 virt, u64 phy, u16 options, char
 
 u64* paging_create_task(int npages){
     u64 *pml4=PAGE_ALLOCATE();
-   // paging_allocate_addr(pml4, 0, (u64)PAGE_ALLOCATE(), PAGING_OPT_P|PAGING_OPT_RW, 0);
+
+    for(int i=0;i<npages;i++)
+        paging_allocate_addr(pml4, 0, (u64)PAGE_ALLOCATE(), PAGING_OPT_P|PAGING_OPT_RW, 0);
+
+    // Enable kernel access
+    u16 pml4_entry=kvar_kernel_vma>>39&0x1FF;
+    pml4[pml4_entry]=kpages[0][pml4_entry];
+
     return pml4;
 }

src/core/paging.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
-#include "core/types.hpp"
+#include "types.hpp"
+#include "asm.hpp"
 
 /**
  * Current number of page (from the beginning of the ram) used by the kernel that

src/drivers/bmp.cc

@@ -28,7 +28,6 @@ void bmp_draw(u8* bmp_data, int posx, int posy){
             p.r=pixel[0];
             p.g=pixel[1];
             p.b=pixel[2];
-            //printk("R%d G%d B%d\n",p.r,p.g,p.b);
             p.a=0;
             framebuffer_draw(p);