Syscall table

include/kernel/ke/syscall.h

@@ -31,6 +31,10 @@
 
 //----------------------------------------------------------------------------//
 
+#define LATEST_SYSCALL_CODE 0
+
+//----------------------------------------------------------------------------//
+
 extern error_t KeSyscall(ulong code);
 
 extern void KeJumpToUserspace(ulong args, void *entryPoint, void *stackAddr);
@@ -38,6 +42,8 @@ extern void KeJumpToUserspace(ulong args, void *entryPoint, void *stackAddr);
 error_t _KeSyscallHandler(  ulong code, void *arg0, void *arg1, void *arg2, 
                             ISRFrame_t *regs );
 
+void KeEnableSyscalls();
+
 //----------------------------------------------------------------------------//
 
 #endif

kaleid/kernel/init/init.c

@@ -77,6 +77,7 @@ noreturn void BtStartKern(multiboot_info_t *mbInfo, uint mbMagic, void *codeSeg)
     KeEnableIRQs();
     KeEnableRTC();
     KeEnablePIT();
+    KeEnableSyscalls();
 
     // Interrupt handlers
     MmActivatePageHandler();

kaleid/kernel/ke/syscall.c

@@ -25,17 +25,49 @@
 #include <libbuf.h>
 #include <init/boot.h>
 #include <ke/idt.h>
+#include <ke/syscall.h>
 #include <io/vga.h>
 
-error_t _KeSyscallHandler(  ulong code, void *arg0, void *arg1, void *arg2, 
+static error_t (*syscallTable[255])(void*, void*, void*, ISRFrame_t*) = {NULL};
+
+
+//
+//  Syscall handler that dispatches calls depending of code value
+//
+error_t _KeSyscallHandler(  ulong code, void *rdi, void *rsi, void *rdx, 
                             ISRFrame_t *regs )
-{
+{    
-    DebugLog("Got a system call code %ld from cs %#x\n", code, regs->cs);
+    if ((ulong)regs->cs >= (ulong)BtLoaderInfo.codeSegment) {
-    
+        DebugLog("System call code %ld from userspace (cs %#x)\n", 
-    if ((ulong)regs->cs != (ulong)BtLoaderInfo.codeSegment) {
+                                                                code, regs->cs);
-        bprintf(BStdOut, "Got a system call from userspace code %d\n", code);
+    } else {
-        BStdOut->flusher(BStdOut);
+        DebugLog("System call call code %ld from kernel (cs %#x)\n", 
+                                                                code, regs->cs);
     }
     
+    if (code > LATEST_SYSCALL_CODE) {
+        return EINVAL;
+    }
+    
+    return syscallTable[(uchar)code](rdi, rsi, rdx, regs);
+    
     return EOK;
 }
+
+//
+//  Syscalls
+//
+static error_t syscallRead(void *rdi, void *rsi, void *rdx, ISRFrame_t *regs)
+{
+    DebugLog("syscallRead attempted\n");
+    return EOK;
+}
+
+
+//
+//  Initializes the syscall table
+//
+void KeEnableSyscalls()
+{
+    syscallTable[0] = syscallRead;
+}