Merged fancy userspace paging

14 files changed, 78 insertions, 32 deletions

diff --git a/run b/run
index edb1a32..17a42f0 100755
--- a/run
+++ b/run
@@ -107,10 +107,10 @@ make_build() {
     stripped=$(echo "${line}" | sed -r 's/\//_/g')
     stripped=${stripped#??????}
     stripped=${stripped%%?}o
-    compile_with_flags -O3 -c ./"${line}" -I ./src/userspace -o ./build/userspace/"${stripped}"
+    compile_with_flags -O2 -c ./"${line}" -I ./src/userspace -o ./build/userspace/"${stripped}"
   done <./build/tmp
   rm ./build/tmp
-  compile_with_flags -O3 ./build/userspace/*.o -T ./src/userspace/linker.ld -I ./src/userspace -o ./build/user.bin
+  compile_with_flags -O2 ./build/userspace/*.o -T ./src/userspace/linker.ld -I ./src/userspace -o ./build/user.bin
 
   # Create ISO
   mkdir -p ./iso/boot/
diff --git a/src/kernel/boot.asm b/src/kernel/boot.asm
index 6b95f4c..85d4254 100644
--- a/src/kernel/boot.asm
+++ b/src/kernel/boot.asm
@@ -29,7 +29,11 @@ section .text
     global jump_userspace
     jump_userspace:
         cli
-        mov ebx, dword [esp + 4]
+        push ebp
+        mov ebp, esp
+        mov edx, dword [esp + 0xC]
+        mov esp, edx
+        push 0xABCDEF
 
         mov ax, 0x23
         mov ds, ax
@@ -48,10 +52,12 @@ section .text
         push eax
 
         push 0x1B
-        push ebx
-        mov ebp, ebx
+        push dword [ebp + 8]
         iret
 
+        pop ebp
+        ret
+
 section .end_section
     global ASM_KERNEL_END
     ASM_KERNEL_END:
diff --git a/src/kernel/gdt/gdt.c b/src/kernel/gdt/gdt.c
index 49d5ce6..435528a 100644
--- a/src/kernel/gdt/gdt.c
+++ b/src/kernel/gdt/gdt.c
@@ -2,7 +2,7 @@
 #include <kernel/gdt/gdt.h>
 #include <kernel/system.h>
 #include <kernel/lib/lib.h>
-#include <kernel/lib/stdlib/liballoc.h>
+#include <kernel/lib/stdlib.h>
 
 struct gdt_entry {
     unsigned short limit_low;
@@ -93,7 +93,7 @@ void gdt_install()
     gdt_set_gate(4, 0, 0xFFFFFFFF, 0xF2, 0xCF);
 
     // Write TSS
-    tss_write(5, 0x10);
+    tss_write(5, 0x10, 0x0);
 
     // Remove old GDT and install the new changes!
     gdt_flush();
@@ -101,7 +101,7 @@ void gdt_install()
     vga_log("Installed Global Descriptor Table");
 }
 
-void tss_write(int32_t num, uint16_t ss0)
+void tss_write(int32_t num, uint16_t ss0, uint32_t esp0)
 {
     uint32_t base = (uint32_t) &tss_entry;
     uint32_t limit = base + sizeof(tss_entry);
@@ -111,13 +111,20 @@ void tss_write(int32_t num, uint16_t ss0)
     memset(&tss_entry, 0, sizeof(tss_entry));
 
     tss_entry.ss0 = ss0;
-    tss_entry.iomap_base = sizeof(struct tss_entry_struct);
+    tss_entry.esp0 = esp0;
     tss_entry.cs = 0x0b;
     tss_entry.ss = tss_entry.ds = tss_entry.es = tss_entry.fs = tss_entry.gs = 0x13;
+
+    tss_entry.iomap_base = sizeof(struct tss_entry_struct);
 }
 
 void tss_flush(void)
 {
-    tss_entry.esp0 = 4096 + (uint32_t) kmalloc(4096);
+    tss_entry.esp0 = 4096 + (uint32_t) umalloc(4096);
     asm volatile ("ltr %%ax": : "a" (0x2B));
+}
+
+void set_kernel_stack(uintptr_t stack)
+{
+    tss_entry.esp0 = stack;
 }
\ No newline at end of file
diff --git a/src/kernel/gdt/gdt.h b/src/kernel/gdt/gdt.h
index da36445..0e77103 100644
--- a/src/kernel/gdt/gdt.h
+++ b/src/kernel/gdt/gdt.h
@@ -6,8 +6,10 @@
  */
 void gdt_install();
 
-void tss_write(int32_t num, uint16_t ss0);
+void tss_write(int32_t num, uint16_t ss0, uint32_t esp0);
 
 void tss_flush();
 
+void set_kernel_stack(uintptr_t stack);
+
 #endif
diff --git a/src/kernel/interrupts/isr.c b/src/kernel/interrupts/isr.c
index eb932b2..8b2a9e5 100644
--- a/src/kernel/interrupts/isr.c
+++ b/src/kernel/interrupts/isr.c
@@ -3,6 +3,7 @@
 #include <kernel/system.h>
 #include <kernel/lib/string.h>
 #include <kernel/lib/stdio.h>
+#include <kernel/paging/paging.h>
 
 // Install ISRs in IDT
 void isrs_install()
@@ -116,6 +117,7 @@ void fault_handler(struct regs *r)
                 r->eip, r->eax, r->ebx, r->ecx, r->edx, r->esp, faulting_address, r->eflags, r->err_code, r->int_no,
                 exception_messages[r->int_no]
         );
+        serial_printf("%d", paging_get_flags(faulting_address));
         // halt_loop(); // Idk loop?
         char *message = (char *) exception_messages[r->int_no];
         strcat(message, " Exception");
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index d8f8c66..b2b7ada 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -60,18 +60,19 @@ void kernel_main()
     info("Switching to user mode...");
     syscalls_install();
     tss_flush();
-    uint32_t userspace = paging_alloc_pages(10);
-    paging_set_user(userspace, 10);
+    uint32_t userspace = (uint32_t) umalloc(8096);
+    paging_switch_directory(1);
     if (boot_drive_id == 0xE0) {
         char *user_p[] = {"USER.BIN"};
         struct iso9660_entity *user_e = ISO9660_get(user_p, 1);
         if (!user_e) panic("Userspace binary not found!");
         ATAPI_granular_read(1 + (user_e->length / 2048), user_e->lba, (uint8_t *) (userspace + 4096));
         kfree(user_e);
-        jump_userspace(userspace + 4096);
+        jump_userspace(userspace + 4096, userspace + 4096);
     } else {
         marfs_read_whole_file(4, (uint8_t *) (userspace + 4096));
-        jump_userspace(userspace + 4096);
+        paging_switch_directory(1);
+        jump_userspace(userspace + 4096, userspace + 4096);
     }
 
     panic("This should NOT happen!");
diff --git a/src/kernel/lib/stdlib/liballoc.c b/src/kernel/lib/stdlib/liballoc.c
index e05cc24..c1a5de1 100644
--- a/src/kernel/lib/stdlib/liballoc.c
+++ b/src/kernel/lib/stdlib/liballoc.c
@@ -472,6 +472,7 @@ void *krealloc(void *p, size_t size)
 
 void *umalloc(size_t req_size)
 {
+    paging_switch_directory(1);
     int started_bet = 0;
     unsigned long long best_size = 0;
     void *p = NULL;
@@ -497,6 +498,7 @@ void *umalloc(size_t req_size)
         l_mem_root_user = allocate_new_page(size, 1);
         if (l_mem_root_user == NULL) {
             liballoc_unlock();
+            paging_switch_directory(0);
             return NULL;
         }
     }
@@ -554,6 +556,7 @@ void *umalloc(size_t req_size)
             p = (void *) ((uintptr_t) (maj->first) + sizeof(struct liballoc_minor));
             ALIGN(p);
             liballoc_unlock();
+            paging_switch_directory(0);
             return p;
         }
 
@@ -576,6 +579,7 @@ void *umalloc(size_t req_size)
             p = (void *) ((uintptr_t) (maj->first) + sizeof(struct liballoc_minor));
             ALIGN(p);
             liballoc_unlock();
+            paging_switch_directory(0);
             return p;
         }
 
@@ -601,6 +605,7 @@ void *umalloc(size_t req_size)
                     p = (void *) ((uintptr_t) min + sizeof(struct liballoc_minor));
                     ALIGN(p);
                     liballoc_unlock();
+                    paging_switch_directory(0);
                     return p;
                 }
             }
@@ -626,6 +631,7 @@ void *umalloc(size_t req_size)
                     p = (void *) ((uintptr_t) new_min + sizeof(struct liballoc_minor));
                     ALIGN(p);
                     liballoc_unlock();
+                    paging_switch_directory(0);
                     return p;
                 }
             }
@@ -649,16 +655,19 @@ void *umalloc(size_t req_size)
 
     liballoc_unlock();
 
+    paging_switch_directory(0);
     return NULL;
 }
 
 void ufree(void *ptr)
 {
+    paging_switch_directory(1);
     struct liballoc_minor *min;
     struct liballoc_major *maj;
 
     if (ptr == NULL) {
         l_warning_count_user += 1;
+        paging_switch_directory(0);
         return;
     }
 
@@ -677,6 +686,7 @@ void ufree(void *ptr)
         }
 
         liballoc_unlock();
+        paging_switch_directory(0);
         return;
     }
 
@@ -703,10 +713,12 @@ void ufree(void *ptr)
         }
     }
     liballoc_unlock();
+    paging_switch_directory(0);
 }
 
 void *ucalloc(size_t nobj, size_t size)
 {
+    paging_switch_directory(1);
     int real_size;
     void *p;
 
@@ -716,17 +728,20 @@ void *ucalloc(size_t nobj, size_t size)
 
     liballoc_memset(p, 0, real_size);
 
+    paging_switch_directory(0);
     return p;
 }
 
 void *urealloc(void *p, size_t size)
 {
+    paging_switch_directory(1);
     void *ptr;
     struct liballoc_minor *min;
     unsigned int real_size;
 
     if (size == 0) {
         ufree(p);
+        paging_switch_directory(0);
         return NULL;
     }
 
@@ -746,6 +761,7 @@ void *urealloc(void *p, size_t size)
         }
 
         liballoc_unlock();
+        paging_switch_directory(0);
         return NULL;
     }
 
@@ -754,6 +770,7 @@ void *urealloc(void *p, size_t size)
     if (real_size >= size) {
         min->req_size = size;
         liballoc_unlock();
+        paging_switch_directory(0);
         return p;
     }
 
@@ -763,5 +780,6 @@ void *urealloc(void *p, size_t size)
     liballoc_memcpy(ptr, p, real_size);
     ufree(p);
 
+    paging_switch_directory(0);
     return ptr;
 }
\ No newline at end of file
diff --git a/src/kernel/paging/paging.c b/src/kernel/paging/paging.c
index 6f7833d..c4a2940 100644
--- a/src/kernel/paging/paging.c
+++ b/src/kernel/paging/paging.c
@@ -12,11 +12,8 @@ uint32_t kernel_page_tables[1024][1024] __attribute__((aligned(4096)));
 uint32_t user_page_directory[1024] __attribute__((aligned(4096)));
 uint32_t user_page_tables[1024][1024] __attribute__((aligned(4096)));
 
-void paging_install()
+void paging_init()
 {
-    current_page_directory = kernel_page_directory;
-    current_page_tables = kernel_page_tables;
-
     for (uint32_t i = 0; i < 1024; i++) {
         for (uint32_t j = 0; j < 1024; j++) {
             current_page_tables[i][j] = ((j * 0x1000) + (i * 0x400000)) | PT_RW;
@@ -27,7 +24,19 @@ void paging_install()
         current_page_directory[i] = ((uint32_t) current_page_tables[i]) | PD_RW | PD_PRESENT;
     }
 
-    paging_set_present(0, memory_get_all() >> 2); // /4
+    paging_set_present(0, memory_get_all() >> 3); // /4
+}
+
+void paging_install()
+{
+    // User paging
+    paging_switch_directory(1);
+    paging_init();
+    paging_set_user(0, memory_get_all() >> 3);
+
+    // Kernel paging
+    paging_switch_directory(0);
+    paging_init();
     paging_set_used(0, ((uint32_t) ASM_KERNEL_END >> 12) + 1); // /4096
 
     paging_enable();
@@ -44,9 +53,9 @@ void paging_disable()
     paging_enabled = 0;
 }
 
-void paging_switch_directory()
+void paging_switch_directory(int user)
 {
-    if (current_page_tables == kernel_page_tables) {
+    if (user == 1) {
         current_page_tables = user_page_tables;
         current_page_directory = user_page_directory;
     } else {
diff --git a/src/kernel/paging/paging.h b/src/kernel/paging/paging.h
index 684c3b2..b75bbe3 100644
--- a/src/kernel/paging/paging.h
+++ b/src/kernel/paging/paging.h
@@ -29,7 +29,7 @@ void paging_enable();
 
 void paging_disable();
 
-void paging_switch_directory();
+void paging_switch_directory(int user);
 
 void paging_map(uint32_t phy, uint32_t virt, uint16_t flags);
 
diff --git a/src/kernel/syscall/syscall.c b/src/kernel/syscall/syscall.c
index 7ca7f99..93abc83 100644
--- a/src/kernel/syscall/syscall.c
+++ b/src/kernel/syscall/syscall.c
@@ -3,9 +3,12 @@
 #include <kernel/interrupts/interrupts.h>
 #include <kernel/system.h>
 #include <kernel/lib/stdio.h>
+#include <kernel/paging/paging.h>
 
 typedef uint32_t (*syscall_func)(unsigned int, ...);
 
+extern void jump_userspace();
+
 uint32_t (*syscalls[])() = {
         [0] = (uint32_t (*)()) halt_loop, // DEBUG!
         [1] = sys_write,
@@ -19,6 +22,7 @@ uint32_t (*syscalls[])() = {
 
 void syscall_handler(struct regs *r)
 {
+    paging_switch_directory(0);
     serial_printf("Received syscall!");
 
     if (r->eax >= sizeof(syscalls) / sizeof(*syscalls))
@@ -31,6 +35,7 @@ void syscall_handler(struct regs *r)
     //serial_printf("[SYSCALL] %d (0x%x) 0x%x 0x%x 0x%x 0x%x 0x%x", r->eax, location, r->ebx, r->ecx, r->edx, r->esi, r->edi);
 
     r->eax = location(r->ebx, r->ecx, r->edx, r->esi, r->edi);
+    paging_switch_directory(1);
 }
 
 void syscalls_install()
diff --git a/src/kernel/system.c b/src/kernel/system.c
index c37c890..c01fb46 100644
--- a/src/kernel/system.c
+++ b/src/kernel/system.c
@@ -106,7 +106,6 @@ void assert(int x)
 
 void halt_loop()
 {
-    serial_printf("\n!!! HALT !!!");
     asm ("cli");
     loop:
     asm ("hlt");
diff --git a/src/userspace/main.c b/src/userspace/main.c
index 6149573..c2307a8 100644
--- a/src/userspace/main.c
+++ b/src/userspace/main.c
@@ -14,6 +14,9 @@ void user_main()
     char text[] = "> Successfully switched to usermode!\n";
     printf(text);
 
+    // TODO: PLEASE
+    printf("If this message shows up, I'll be happy.\n");
+
     while (1) {
         char *input = readline();
         if (starts_with(input, "ls")) {
diff --git a/src/userspace/mlibc/stdio/printf.c b/src/userspace/mlibc/stdio/printf.c
index b582897..5617d03 100644
--- a/src/userspace/mlibc/stdio/printf.c
+++ b/src/userspace/mlibc/stdio/printf.c
@@ -1,14 +1,10 @@
 #include <stdarg.h>
 #include <mlibc/stdio.h>
-#include <mlibc/string.h>
-#include <mlibc/stdlib.h>
 
 void printf(const char *fmt, ...)
 {
-    char *format = (char *) malloc(strlen(fmt));
-    strcpy(format, fmt);
     va_list args;
     va_start(args, fmt);
-    vprintf(format, args);
+    vprintf(fmt, args);
     va_end(args);
 }
\ No newline at end of file
diff --git a/src/userspace/start.asm b/src/userspace/start.asm
index 7348825..c6bb2a0 100644
--- a/src/userspace/start.asm
+++ b/src/userspace/start.asm
@@ -4,6 +4,4 @@ section .text
     global _start
     extern user_main
     _start:
-        mov esp, ebp
-        call user_main
-        jmp $
\ No newline at end of file
+        call user_main
\ No newline at end of file