diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret
diff --git a/src/kernel/service/services.c b/src/kernel/service/services.c
index 450b4b2..a61ff1d 100644
--- a/src/kernel/service/services.c
+++ b/src/kernel/service/services.c
@@ -13,9 +13,6 @@
 
 void resume(Syscall *syscall) {
     currentSyscall = syscall;
-    if (!syscall->address) {
-        asm("hlt" ::"a"(syscall));
-    }
     runFunction();
 }
 

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret
diff --git a/src/kernel/service/services.c b/src/kernel/service/services.c
index 450b4b2..a61ff1d 100644
--- a/src/kernel/service/services.c
+++ b/src/kernel/service/services.c
@@ -13,9 +13,6 @@
 
 void resume(Syscall *syscall) {
     currentSyscall = syscall;
-    if (!syscall->address) {
-        asm("hlt" ::"a"(syscall));
-    }
     runFunction();
 }
 
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index 51dd4c4..541cea0 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -5,7 +5,6 @@
 #include <syscalls.h>
 #include <util.h>
 
-extern void *runEndSyscall;
 extern ListElement *callsToProcess;
 extern void(syscallStub)();
 extern Syscall *currentSyscall;
@@ -19,30 +18,30 @@
           0); // when transitioning to 64 bit: U32(value) >> 32);
 }
 
-void handleSyscall(void *cr3, Syscall *callData) {
-    if (!callData) {
+void handleSyscall(void *esp, uint32_t function, uint32_t parameter0,
+                   uint32_t parameter1, uint32_t parameter2,
+                   uint32_t parameter3) {
+    if (!function) {
         if (currentSyscall->respondingTo) {
             listAdd(&callsToProcess, currentSyscall->respondingTo);
         }
-        asm("jmp runEndSyscall");
+        return;
     }
-    Service *service = currentSyscall->service;
-    void *dataPhysical =
-        getPhysicalAddress(service->pagingInfo.pageDirectory, callData);
-    Syscall *call = malloc(sizeof(RequestSyscall));
-    void *data = mapTemporary(dataPhysical);
-    memcpy(data, call, sizeof(RequestSyscall));
-    call->cr3 = cr3;
+    Syscall *call = malloc(sizeof(Syscall));
+    call->function = function;
+    call->parameters[0] = parameter0;
+    call->parameters[1] = parameter1;
+    call->parameters[2] = parameter2;
+    call->parameters[3] = parameter3;
     call->service = currentSyscall->service;
-    call->writeBack = dataPhysical;
+    call->esp = esp;
     if (!call->respondingTo) {
         call->respondingTo = currentSyscall->respondingTo;
     }
-    if (!call->address) {
-        asm("hlt" ::"a"(call), "b"(dataPhysical));
-    }
+    Service *currentService = currentSyscall->service;
+    call->cr3 =
+        getPhysicalAddressKernel(currentService->pagingInfo.pageDirectory);
     listAdd(&callsToProcess, call);
-    asm("jmp runEndSyscall");
 }
 
 void *syscallStubPtr = syscallStub;
@@ -53,28 +52,33 @@
     writeMsrRegister(0x176, syscallStubPtr);          // the handler
 }
 
-void handleInstallSyscall(RegisterServiceProviderSyscall *call) {
+void handleInstallSyscall(Syscall *call) {
     Provider *provider = malloc(sizeof(Provider));
     Service *service = call->service;
-    char *providerName = kernelMapPhysical(
-        getPhysicalAddress(service->pagingInfo.pageDirectory, call->name));
+    char *providerName = kernelMapPhysical(getPhysicalAddress(
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     provider->name = providerName;
-    provider->address = call->handler;
+    provider->address = PTR(call->parameters[1]);
     provider->service = call->service;
     listAdd(&service->providers, provider);
 }
 
-void handleRequestSyscall(RequestSyscall *call) {
+void *listGet(ListElement *list, uint32_t position) {
+    for (uint32_t i = 0; i < position; i++) {
+        list = list->next;
+    }
+    return list->data;
+}
+
+extern ListElement *services;
+
+void handleRequestSyscall(Syscall *call) {
     Service *service = call->service;
-    char *serviceName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->serviceName));
-    Service *providerService = findService(serviceName);
-    char *providerName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->providerName));
-    Provider *callProvider = findProvider(providerService, providerName);
+    Service *providerService = listGet(services, call->parameters[0]);
+    Provider *provider =
+        listGet(providerService->providers, call->parameters[1]);
     Syscall *runCall = malloc(sizeof(Syscall));
     runCall->function = SYS_RUN;
-    runCall->address = callProvider->address;
     runCall->esp = malloc(0x1000);
     runCall->respondingTo = (void *)call;
     runCall->cr3 =
@@ -82,50 +86,94 @@
     runCall->service = providerService;
     runCall->resume = true;
     sharePage(&providerService->pagingInfo, runCall->esp, runCall->esp);
-    runCall->esp += 0xFFC;
-    *(void **)runCall->esp = &runEnd;
+    runCall->esp += 0xFF8;
+    *(void **)runCall->esp = provider->address;
+    *(void **)(runCall->esp + 4) = &runEnd;
     listAdd(&callsToProcess, runCall);
     call->avoidReschedule = true;
 }
 
-void handleIOInSyscall(IOPortInSyscall *call) {
-    switch (call->size) {
+void handleIOInSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("in %%dx, %%al" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%al"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 2:
-        asm("in %%dx, %%ax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%ax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 4:
-        asm("in %%dx, %%eax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%eax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     }
 }
 
-void handleIOOutSyscall(IOPortOutSyscall *call) {
-    switch (call->size) {
+void handleIOOutSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("out %0, %1" : : "a"((uint8_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint8_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 2:
-        asm("out %0, %1" : : "a"((uint16_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint16_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 4:
-        asm("out %0, %1" : : "a"((uint32_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint32_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     }
 }
 
 extern Syscall *loadInitrdProgram(char *name, Syscall *respondingTo);
 
-void handleLoadFromInitrdSyscall(LoadFromInitrdSyscall *call) {
+void handleLoadFromInitrdSyscall(Syscall *call) {
     Service *service = call->service;
     char *programName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->programName));
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     loadInitrdProgram(programName, (void *)call);
     call->avoidReschedule = true;
 }
 
+void handleGetServiceSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[0])));
+    foreach (services, Service *, service, {
+        if (stringEquals(service->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
+void handleGetProviderSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[1])));
+    Service *providerService = listGet(services, call->parameters[0]);
+    foreach (providerService->providers, Provider *, provider, {
+        if (stringEquals(provider->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
 void (*syscallHandlers[])(Syscall *) = {
     0,
     (void *)handleInstallSyscall,
@@ -133,4 +181,6 @@
     (void *)handleIOInSyscall,
     (void *)handleIOOutSyscall,
     (void *)handleLoadFromInitrdSyscall,
+    (void *)handleGetServiceSyscall,
+    (void *)handleGetProviderSyscall,
 };

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret
diff --git a/src/kernel/service/services.c b/src/kernel/service/services.c
index 450b4b2..a61ff1d 100644
--- a/src/kernel/service/services.c
+++ b/src/kernel/service/services.c
@@ -13,9 +13,6 @@
 
 void resume(Syscall *syscall) {
     currentSyscall = syscall;
-    if (!syscall->address) {
-        asm("hlt" ::"a"(syscall));
-    }
     runFunction();
 }
 
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index 51dd4c4..541cea0 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -5,7 +5,6 @@
 #include <syscalls.h>
 #include <util.h>
 
-extern void *runEndSyscall;
 extern ListElement *callsToProcess;
 extern void(syscallStub)();
 extern Syscall *currentSyscall;
@@ -19,30 +18,30 @@
           0); // when transitioning to 64 bit: U32(value) >> 32);
 }
 
-void handleSyscall(void *cr3, Syscall *callData) {
-    if (!callData) {
+void handleSyscall(void *esp, uint32_t function, uint32_t parameter0,
+                   uint32_t parameter1, uint32_t parameter2,
+                   uint32_t parameter3) {
+    if (!function) {
         if (currentSyscall->respondingTo) {
             listAdd(&callsToProcess, currentSyscall->respondingTo);
         }
-        asm("jmp runEndSyscall");
+        return;
     }
-    Service *service = currentSyscall->service;
-    void *dataPhysical =
-        getPhysicalAddress(service->pagingInfo.pageDirectory, callData);
-    Syscall *call = malloc(sizeof(RequestSyscall));
-    void *data = mapTemporary(dataPhysical);
-    memcpy(data, call, sizeof(RequestSyscall));
-    call->cr3 = cr3;
+    Syscall *call = malloc(sizeof(Syscall));
+    call->function = function;
+    call->parameters[0] = parameter0;
+    call->parameters[1] = parameter1;
+    call->parameters[2] = parameter2;
+    call->parameters[3] = parameter3;
     call->service = currentSyscall->service;
-    call->writeBack = dataPhysical;
+    call->esp = esp;
     if (!call->respondingTo) {
         call->respondingTo = currentSyscall->respondingTo;
     }
-    if (!call->address) {
-        asm("hlt" ::"a"(call), "b"(dataPhysical));
-    }
+    Service *currentService = currentSyscall->service;
+    call->cr3 =
+        getPhysicalAddressKernel(currentService->pagingInfo.pageDirectory);
     listAdd(&callsToProcess, call);
-    asm("jmp runEndSyscall");
 }
 
 void *syscallStubPtr = syscallStub;
@@ -53,28 +52,33 @@
     writeMsrRegister(0x176, syscallStubPtr);          // the handler
 }
 
-void handleInstallSyscall(RegisterServiceProviderSyscall *call) {
+void handleInstallSyscall(Syscall *call) {
     Provider *provider = malloc(sizeof(Provider));
     Service *service = call->service;
-    char *providerName = kernelMapPhysical(
-        getPhysicalAddress(service->pagingInfo.pageDirectory, call->name));
+    char *providerName = kernelMapPhysical(getPhysicalAddress(
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     provider->name = providerName;
-    provider->address = call->handler;
+    provider->address = PTR(call->parameters[1]);
     provider->service = call->service;
     listAdd(&service->providers, provider);
 }
 
-void handleRequestSyscall(RequestSyscall *call) {
+void *listGet(ListElement *list, uint32_t position) {
+    for (uint32_t i = 0; i < position; i++) {
+        list = list->next;
+    }
+    return list->data;
+}
+
+extern ListElement *services;
+
+void handleRequestSyscall(Syscall *call) {
     Service *service = call->service;
-    char *serviceName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->serviceName));
-    Service *providerService = findService(serviceName);
-    char *providerName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->providerName));
-    Provider *callProvider = findProvider(providerService, providerName);
+    Service *providerService = listGet(services, call->parameters[0]);
+    Provider *provider =
+        listGet(providerService->providers, call->parameters[1]);
     Syscall *runCall = malloc(sizeof(Syscall));
     runCall->function = SYS_RUN;
-    runCall->address = callProvider->address;
     runCall->esp = malloc(0x1000);
     runCall->respondingTo = (void *)call;
     runCall->cr3 =
@@ -82,50 +86,94 @@
     runCall->service = providerService;
     runCall->resume = true;
     sharePage(&providerService->pagingInfo, runCall->esp, runCall->esp);
-    runCall->esp += 0xFFC;
-    *(void **)runCall->esp = &runEnd;
+    runCall->esp += 0xFF8;
+    *(void **)runCall->esp = provider->address;
+    *(void **)(runCall->esp + 4) = &runEnd;
     listAdd(&callsToProcess, runCall);
     call->avoidReschedule = true;
 }
 
-void handleIOInSyscall(IOPortInSyscall *call) {
-    switch (call->size) {
+void handleIOInSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("in %%dx, %%al" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%al"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 2:
-        asm("in %%dx, %%ax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%ax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 4:
-        asm("in %%dx, %%eax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%eax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     }
 }
 
-void handleIOOutSyscall(IOPortOutSyscall *call) {
-    switch (call->size) {
+void handleIOOutSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("out %0, %1" : : "a"((uint8_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint8_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 2:
-        asm("out %0, %1" : : "a"((uint16_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint16_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 4:
-        asm("out %0, %1" : : "a"((uint32_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint32_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     }
 }
 
 extern Syscall *loadInitrdProgram(char *name, Syscall *respondingTo);
 
-void handleLoadFromInitrdSyscall(LoadFromInitrdSyscall *call) {
+void handleLoadFromInitrdSyscall(Syscall *call) {
     Service *service = call->service;
     char *programName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->programName));
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     loadInitrdProgram(programName, (void *)call);
     call->avoidReschedule = true;
 }
 
+void handleGetServiceSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[0])));
+    foreach (services, Service *, service, {
+        if (stringEquals(service->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
+void handleGetProviderSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[1])));
+    Service *providerService = listGet(services, call->parameters[0]);
+    foreach (providerService->providers, Provider *, provider, {
+        if (stringEquals(provider->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
 void (*syscallHandlers[])(Syscall *) = {
     0,
     (void *)handleInstallSyscall,
@@ -133,4 +181,6 @@
     (void *)handleIOInSyscall,
     (void *)handleIOOutSyscall,
     (void *)handleLoadFromInitrdSyscall,
+    (void *)handleGetServiceSyscall,
+    (void *)handleGetProviderSyscall,
 };
diff --git a/src/kernel/syscalls/syscallStub.asm b/src/kernel/syscalls/syscallStub.asm
index ad29d6e..f8213a8 100644
--- a/src/kernel/syscalls/syscallStub.asm
+++ b/src/kernel/syscalls/syscallStub.asm
@@ -3,16 +3,23 @@
 
 global syscallStub
 extern handleSyscall
+extern temporaryESP
+
+temporaryEAX: resb 4
 
 syscallStub:
-  mov ebx, cr3
-  mov ecx, 0x500000
-  mov cr3, ecx
-  push eax
+  mov [temporaryEAX], eax
+  mov eax, 0x500000
+  mov cr3, eax
+  mov eax, [temporaryEAX]
+  push esi
+  push edx
+  push ecx
   push ebx
+  push eax
+  push edi
   call handleSyscall
-  pop ebx
-  mov edx, [eax+4]
-  mov ecx, [eax+8]
-  mov cr3, ebx
-  sysexit
+  mov eax, [temporaryESP]
+  mov esp, eax
+  pop ebp
+  ret

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret
diff --git a/src/kernel/service/services.c b/src/kernel/service/services.c
index 450b4b2..a61ff1d 100644
--- a/src/kernel/service/services.c
+++ b/src/kernel/service/services.c
@@ -13,9 +13,6 @@
 
 void resume(Syscall *syscall) {
     currentSyscall = syscall;
-    if (!syscall->address) {
-        asm("hlt" ::"a"(syscall));
-    }
     runFunction();
 }
 
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index 51dd4c4..541cea0 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -5,7 +5,6 @@
 #include <syscalls.h>
 #include <util.h>
 
-extern void *runEndSyscall;
 extern ListElement *callsToProcess;
 extern void(syscallStub)();
 extern Syscall *currentSyscall;
@@ -19,30 +18,30 @@
           0); // when transitioning to 64 bit: U32(value) >> 32);
 }
 
-void handleSyscall(void *cr3, Syscall *callData) {
-    if (!callData) {
+void handleSyscall(void *esp, uint32_t function, uint32_t parameter0,
+                   uint32_t parameter1, uint32_t parameter2,
+                   uint32_t parameter3) {
+    if (!function) {
         if (currentSyscall->respondingTo) {
             listAdd(&callsToProcess, currentSyscall->respondingTo);
         }
-        asm("jmp runEndSyscall");
+        return;
     }
-    Service *service = currentSyscall->service;
-    void *dataPhysical =
-        getPhysicalAddress(service->pagingInfo.pageDirectory, callData);
-    Syscall *call = malloc(sizeof(RequestSyscall));
-    void *data = mapTemporary(dataPhysical);
-    memcpy(data, call, sizeof(RequestSyscall));
-    call->cr3 = cr3;
+    Syscall *call = malloc(sizeof(Syscall));
+    call->function = function;
+    call->parameters[0] = parameter0;
+    call->parameters[1] = parameter1;
+    call->parameters[2] = parameter2;
+    call->parameters[3] = parameter3;
     call->service = currentSyscall->service;
-    call->writeBack = dataPhysical;
+    call->esp = esp;
     if (!call->respondingTo) {
         call->respondingTo = currentSyscall->respondingTo;
     }
-    if (!call->address) {
-        asm("hlt" ::"a"(call), "b"(dataPhysical));
-    }
+    Service *currentService = currentSyscall->service;
+    call->cr3 =
+        getPhysicalAddressKernel(currentService->pagingInfo.pageDirectory);
     listAdd(&callsToProcess, call);
-    asm("jmp runEndSyscall");
 }
 
 void *syscallStubPtr = syscallStub;
@@ -53,28 +52,33 @@
     writeMsrRegister(0x176, syscallStubPtr);          // the handler
 }
 
-void handleInstallSyscall(RegisterServiceProviderSyscall *call) {
+void handleInstallSyscall(Syscall *call) {
     Provider *provider = malloc(sizeof(Provider));
     Service *service = call->service;
-    char *providerName = kernelMapPhysical(
-        getPhysicalAddress(service->pagingInfo.pageDirectory, call->name));
+    char *providerName = kernelMapPhysical(getPhysicalAddress(
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     provider->name = providerName;
-    provider->address = call->handler;
+    provider->address = PTR(call->parameters[1]);
     provider->service = call->service;
     listAdd(&service->providers, provider);
 }
 
-void handleRequestSyscall(RequestSyscall *call) {
+void *listGet(ListElement *list, uint32_t position) {
+    for (uint32_t i = 0; i < position; i++) {
+        list = list->next;
+    }
+    return list->data;
+}
+
+extern ListElement *services;
+
+void handleRequestSyscall(Syscall *call) {
     Service *service = call->service;
-    char *serviceName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->serviceName));
-    Service *providerService = findService(serviceName);
-    char *providerName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->providerName));
-    Provider *callProvider = findProvider(providerService, providerName);
+    Service *providerService = listGet(services, call->parameters[0]);
+    Provider *provider =
+        listGet(providerService->providers, call->parameters[1]);
     Syscall *runCall = malloc(sizeof(Syscall));
     runCall->function = SYS_RUN;
-    runCall->address = callProvider->address;
     runCall->esp = malloc(0x1000);
     runCall->respondingTo = (void *)call;
     runCall->cr3 =
@@ -82,50 +86,94 @@
     runCall->service = providerService;
     runCall->resume = true;
     sharePage(&providerService->pagingInfo, runCall->esp, runCall->esp);
-    runCall->esp += 0xFFC;
-    *(void **)runCall->esp = &runEnd;
+    runCall->esp += 0xFF8;
+    *(void **)runCall->esp = provider->address;
+    *(void **)(runCall->esp + 4) = &runEnd;
     listAdd(&callsToProcess, runCall);
     call->avoidReschedule = true;
 }
 
-void handleIOInSyscall(IOPortInSyscall *call) {
-    switch (call->size) {
+void handleIOInSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("in %%dx, %%al" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%al"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 2:
-        asm("in %%dx, %%ax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%ax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 4:
-        asm("in %%dx, %%eax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%eax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     }
 }
 
-void handleIOOutSyscall(IOPortOutSyscall *call) {
-    switch (call->size) {
+void handleIOOutSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("out %0, %1" : : "a"((uint8_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint8_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 2:
-        asm("out %0, %1" : : "a"((uint16_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint16_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 4:
-        asm("out %0, %1" : : "a"((uint32_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint32_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     }
 }
 
 extern Syscall *loadInitrdProgram(char *name, Syscall *respondingTo);
 
-void handleLoadFromInitrdSyscall(LoadFromInitrdSyscall *call) {
+void handleLoadFromInitrdSyscall(Syscall *call) {
     Service *service = call->service;
     char *programName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->programName));
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     loadInitrdProgram(programName, (void *)call);
     call->avoidReschedule = true;
 }
 
+void handleGetServiceSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[0])));
+    foreach (services, Service *, service, {
+        if (stringEquals(service->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
+void handleGetProviderSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[1])));
+    Service *providerService = listGet(services, call->parameters[0]);
+    foreach (providerService->providers, Provider *, provider, {
+        if (stringEquals(provider->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
 void (*syscallHandlers[])(Syscall *) = {
     0,
     (void *)handleInstallSyscall,
@@ -133,4 +181,6 @@
     (void *)handleIOInSyscall,
     (void *)handleIOOutSyscall,
     (void *)handleLoadFromInitrdSyscall,
+    (void *)handleGetServiceSyscall,
+    (void *)handleGetProviderSyscall,
 };
diff --git a/src/kernel/syscalls/syscallStub.asm b/src/kernel/syscalls/syscallStub.asm
index ad29d6e..f8213a8 100644
--- a/src/kernel/syscalls/syscallStub.asm
+++ b/src/kernel/syscalls/syscallStub.asm
@@ -3,16 +3,23 @@
 
 global syscallStub
 extern handleSyscall
+extern temporaryESP
+
+temporaryEAX: resb 4
 
 syscallStub:
-  mov ebx, cr3
-  mov ecx, 0x500000
-  mov cr3, ecx
-  push eax
+  mov [temporaryEAX], eax
+  mov eax, 0x500000
+  mov cr3, eax
+  mov eax, [temporaryEAX]
+  push esi
+  push edx
+  push ecx
   push ebx
+  push eax
+  push edi
   call handleSyscall
-  pop ebx
-  mov edx, [eax+4]
-  mov ecx, [eax+8]
-  mov cr3, ebx
-  sysexit
+  mov eax, [temporaryESP]
+  mov esp, eax
+  pop ebp
+  ret
diff --git a/src/kernel/util/list.c b/src/kernel/util/list.c
index aa04956..a5f39fb 100644
--- a/src/kernel/util/list.c
+++ b/src/kernel/util/list.c
@@ -3,9 +3,17 @@
 
 void listAdd(ListElement **list, void *data) {
     ListElement *element = malloc(sizeof(ListElement));
-    element->next = *list;
     element->data = data;
-    *list = element;
+    element->next = NULL;
+    if (!*list) {
+        *list = element;
+        return;
+    }
+    ListElement *current = *list;
+    while (current->next) {
+        current = current->next;
+    }
+    current->next = element;
 }
 
 void *listPopFirst(ListElement **list) {

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret
diff --git a/src/kernel/service/services.c b/src/kernel/service/services.c
index 450b4b2..a61ff1d 100644
--- a/src/kernel/service/services.c
+++ b/src/kernel/service/services.c
@@ -13,9 +13,6 @@
 
 void resume(Syscall *syscall) {
     currentSyscall = syscall;
-    if (!syscall->address) {
-        asm("hlt" ::"a"(syscall));
-    }
     runFunction();
 }
 
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index 51dd4c4..541cea0 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -5,7 +5,6 @@
 #include <syscalls.h>
 #include <util.h>
 
-extern void *runEndSyscall;
 extern ListElement *callsToProcess;
 extern void(syscallStub)();
 extern Syscall *currentSyscall;
@@ -19,30 +18,30 @@
           0); // when transitioning to 64 bit: U32(value) >> 32);
 }
 
-void handleSyscall(void *cr3, Syscall *callData) {
-    if (!callData) {
+void handleSyscall(void *esp, uint32_t function, uint32_t parameter0,
+                   uint32_t parameter1, uint32_t parameter2,
+                   uint32_t parameter3) {
+    if (!function) {
         if (currentSyscall->respondingTo) {
             listAdd(&callsToProcess, currentSyscall->respondingTo);
         }
-        asm("jmp runEndSyscall");
+        return;
     }
-    Service *service = currentSyscall->service;
-    void *dataPhysical =
-        getPhysicalAddress(service->pagingInfo.pageDirectory, callData);
-    Syscall *call = malloc(sizeof(RequestSyscall));
-    void *data = mapTemporary(dataPhysical);
-    memcpy(data, call, sizeof(RequestSyscall));
-    call->cr3 = cr3;
+    Syscall *call = malloc(sizeof(Syscall));
+    call->function = function;
+    call->parameters[0] = parameter0;
+    call->parameters[1] = parameter1;
+    call->parameters[2] = parameter2;
+    call->parameters[3] = parameter3;
     call->service = currentSyscall->service;
-    call->writeBack = dataPhysical;
+    call->esp = esp;
     if (!call->respondingTo) {
         call->respondingTo = currentSyscall->respondingTo;
     }
-    if (!call->address) {
-        asm("hlt" ::"a"(call), "b"(dataPhysical));
-    }
+    Service *currentService = currentSyscall->service;
+    call->cr3 =
+        getPhysicalAddressKernel(currentService->pagingInfo.pageDirectory);
     listAdd(&callsToProcess, call);
-    asm("jmp runEndSyscall");
 }
 
 void *syscallStubPtr = syscallStub;
@@ -53,28 +52,33 @@
     writeMsrRegister(0x176, syscallStubPtr);          // the handler
 }
 
-void handleInstallSyscall(RegisterServiceProviderSyscall *call) {
+void handleInstallSyscall(Syscall *call) {
     Provider *provider = malloc(sizeof(Provider));
     Service *service = call->service;
-    char *providerName = kernelMapPhysical(
-        getPhysicalAddress(service->pagingInfo.pageDirectory, call->name));
+    char *providerName = kernelMapPhysical(getPhysicalAddress(
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     provider->name = providerName;
-    provider->address = call->handler;
+    provider->address = PTR(call->parameters[1]);
     provider->service = call->service;
     listAdd(&service->providers, provider);
 }
 
-void handleRequestSyscall(RequestSyscall *call) {
+void *listGet(ListElement *list, uint32_t position) {
+    for (uint32_t i = 0; i < position; i++) {
+        list = list->next;
+    }
+    return list->data;
+}
+
+extern ListElement *services;
+
+void handleRequestSyscall(Syscall *call) {
     Service *service = call->service;
-    char *serviceName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->serviceName));
-    Service *providerService = findService(serviceName);
-    char *providerName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->providerName));
-    Provider *callProvider = findProvider(providerService, providerName);
+    Service *providerService = listGet(services, call->parameters[0]);
+    Provider *provider =
+        listGet(providerService->providers, call->parameters[1]);
     Syscall *runCall = malloc(sizeof(Syscall));
     runCall->function = SYS_RUN;
-    runCall->address = callProvider->address;
     runCall->esp = malloc(0x1000);
     runCall->respondingTo = (void *)call;
     runCall->cr3 =
@@ -82,50 +86,94 @@
     runCall->service = providerService;
     runCall->resume = true;
     sharePage(&providerService->pagingInfo, runCall->esp, runCall->esp);
-    runCall->esp += 0xFFC;
-    *(void **)runCall->esp = &runEnd;
+    runCall->esp += 0xFF8;
+    *(void **)runCall->esp = provider->address;
+    *(void **)(runCall->esp + 4) = &runEnd;
     listAdd(&callsToProcess, runCall);
     call->avoidReschedule = true;
 }
 
-void handleIOInSyscall(IOPortInSyscall *call) {
-    switch (call->size) {
+void handleIOInSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("in %%dx, %%al" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%al"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 2:
-        asm("in %%dx, %%ax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%ax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 4:
-        asm("in %%dx, %%eax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%eax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     }
 }
 
-void handleIOOutSyscall(IOPortOutSyscall *call) {
-    switch (call->size) {
+void handleIOOutSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("out %0, %1" : : "a"((uint8_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint8_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 2:
-        asm("out %0, %1" : : "a"((uint16_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint16_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 4:
-        asm("out %0, %1" : : "a"((uint32_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint32_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     }
 }
 
 extern Syscall *loadInitrdProgram(char *name, Syscall *respondingTo);
 
-void handleLoadFromInitrdSyscall(LoadFromInitrdSyscall *call) {
+void handleLoadFromInitrdSyscall(Syscall *call) {
     Service *service = call->service;
     char *programName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->programName));
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     loadInitrdProgram(programName, (void *)call);
     call->avoidReschedule = true;
 }
 
+void handleGetServiceSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[0])));
+    foreach (services, Service *, service, {
+        if (stringEquals(service->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
+void handleGetProviderSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[1])));
+    Service *providerService = listGet(services, call->parameters[0]);
+    foreach (providerService->providers, Provider *, provider, {
+        if (stringEquals(provider->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
 void (*syscallHandlers[])(Syscall *) = {
     0,
     (void *)handleInstallSyscall,
@@ -133,4 +181,6 @@
     (void *)handleIOInSyscall,
     (void *)handleIOOutSyscall,
     (void *)handleLoadFromInitrdSyscall,
+    (void *)handleGetServiceSyscall,
+    (void *)handleGetProviderSyscall,
 };
diff --git a/src/kernel/syscalls/syscallStub.asm b/src/kernel/syscalls/syscallStub.asm
index ad29d6e..f8213a8 100644
--- a/src/kernel/syscalls/syscallStub.asm
+++ b/src/kernel/syscalls/syscallStub.asm
@@ -3,16 +3,23 @@
 
 global syscallStub
 extern handleSyscall
+extern temporaryESP
+
+temporaryEAX: resb 4
 
 syscallStub:
-  mov ebx, cr3
-  mov ecx, 0x500000
-  mov cr3, ecx
-  push eax
+  mov [temporaryEAX], eax
+  mov eax, 0x500000
+  mov cr3, eax
+  mov eax, [temporaryEAX]
+  push esi
+  push edx
+  push ecx
   push ebx
+  push eax
+  push edi
   call handleSyscall
-  pop ebx
-  mov edx, [eax+4]
-  mov ecx, [eax+8]
-  mov cr3, ebx
-  sysexit
+  mov eax, [temporaryESP]
+  mov esp, eax
+  pop ebp
+  ret
diff --git a/src/kernel/util/list.c b/src/kernel/util/list.c
index aa04956..a5f39fb 100644
--- a/src/kernel/util/list.c
+++ b/src/kernel/util/list.c
@@ -3,9 +3,17 @@
 
 void listAdd(ListElement **list, void *data) {
     ListElement *element = malloc(sizeof(ListElement));
-    element->next = *list;
     element->data = data;
-    *list = element;
+    element->next = NULL;
+    if (!*list) {
+        *list = element;
+        return;
+    }
+    ListElement *current = *list;
+    while (current->next) {
+        current = current->next;
+    }
+    current->next = element;
 }
 
 void *listPopFirst(ListElement **list) {
diff --git a/src/userland/loader/main.c b/src/userland/loader/main.c
index 3a6f72e..271647b 100644
--- a/src/userland/loader/main.c
+++ b/src/userland/loader/main.c
@@ -1,45 +1,30 @@
 #include <stdint.h>
 #include <syscalls.h>
 
-void syscall(void *callData) {
-    Syscall *call = callData;
-    call->respondingTo = 0;
-    call->resume = false;
-    asm("mov %%ebp, %%eax" : "=a"(call->esp));
-    call->address = &&returnAddress;
-    asm("sysenter\n" ::"a"(callData));
-returnAddress:
-    asm("nop");
-    return;
+#define PTR(x) ((void *)(uintptr_t)x)
+#define U32(x) ((uint32_t)(uintptr_t)x)
+
+uint32_t syscall(uint32_t function, uint32_t parameter0, uint32_t parameter1,
+                 uint32_t parameter2, uint32_t parameter3) {
+    uint32_t esp, result;
+    asm("push %%eax" ::"a"(&&end));
+    asm("mov %%esp, %%eax" : "=a"(esp));
+    asm("sysenter\n"
+        :
+        : "a"(function), "b"(parameter0), "c"(parameter1), "d"(parameter2),
+          "S"(parameter3), "D"(esp));
+end:
+    // eax is set by the kernel as the return value
+    asm("nop" : "=a"(result));
+    return result;
 }
 
-void makeRequest(char *moduleName, char *functionName, void *data,
-                 uint32_t size) {
-    RequestSyscall call = {
-        .function = SYS_REQUEST,
-        .serviceName = moduleName,
-        .providerName = functionName,
-        .data = data,
-        .dataSize = size,
-    };
-    syscall(&call);
+void request(uint32_t module, uint32_t function, void *data, uint32_t size) {
+    syscall(SYS_REQUEST, module, function, U32(data), size);
 }
 
 void installServiceProvider(char *name, void(provider)(void *)) {
-    RegisterServiceProviderSyscall call = {
-        .function = SYS_REGISTER_FUNCTION,
-        .name = name,
-        .handler = provider,
-    };
-    syscall(&call);
-}
-
-void loadFromInitrd(char *name) {
-    LoadFromInitrdSyscall call = {
-        .function = SYS_LOAD_INITRD,
-        .programName = name,
-    };
-    syscall(&call);
+    syscall(SYS_REGISTER_FUNCTION, U32(name), U32(provider), 0, 0);
 }
 
 uint32_t strlen(char *string) {
@@ -51,7 +36,23 @@
     return size;
 }
 
-void log(char *message) { makeRequest("log", "log", message, strlen(message)); }
+uint32_t getModule(char *name) {
+    return syscall(SYS_GET_SERVICE, U32(name), strlen(name), 0, 0);
+}
+
+uint32_t getProvider(uint32_t module, char *name) {
+    return syscall(SYS_GET_PROVIDER, module, U32(name), strlen(name), 0);
+}
+
+void loadFromInitrd(char *name) {
+    syscall(SYS_LOAD_INITRD, U32(name), strlen(name), 0, 0);
+}
+
+void log(char *message) {
+    uint32_t module = getModule("log");
+    uint32_t provider = getProvider(module, "log");
+    request(module, provider, message, strlen(message));
+}
 
 int32_t main() {
     loadFromInitrd("log");

diff --git a/src/include/syscalls.h b/src/include/syscalls.h
index e52e178..2a35dd8 100644
--- a/src/include/syscalls.h
+++ b/src/include/syscalls.h
@@ -11,53 +11,20 @@
     SYS_IO_IN = 3,
     SYS_IO_OUT = 4,
     SYS_LOAD_INITRD = 5,
+    SYS_GET_SERVICE = 6,
+    SYS_GET_PROVIDER = 7,
 } SyscallIds;
 
 typedef struct Syscall {
     uint32_t function;
-    void *address;
+    uint32_t parameters[4];
+    uint32_t returnValue;
     void *esp;
     void *cr3;
     struct Syscall *respondingTo;
     void *service;
     bool resume;
     bool avoidReschedule;
-    struct Syscall *writeBack;
 } Syscall;
 
-typedef struct {
-    Syscall;
-    void *handler;
-    char *name;
-} RegisterServiceProviderSyscall;
-
-typedef struct {
-    Syscall;
-    char *serviceName;
-    char *providerName;
-    uint32_t dataSize;
-    void *data;
-} RequestSyscall;
-
-typedef struct {
-    Syscall;
-    uint16_t port;
-    uint8_t size;
-} IOPortSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t result;
-} IOPortInSyscall;
-
-typedef struct {
-    IOPortSyscall;
-    uint32_t value;
-} IOPortOutSyscall;
-
-typedef struct {
-    Syscall;
-    char *programName;
-} LoadFromInitrdSyscall;
-
 #endif
diff --git a/src/kernel/main.c b/src/kernel/main.c
index 49ac65c..a70cf75 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -22,20 +22,17 @@
     Provider *provider = findProvider(service, "main");
     Syscall *runTask = malloc(sizeof(Syscall));
     runTask->function = SYS_RUN;
-    runTask->address = provider->address;
     runTask->resume = true;
     runTask->cr3 = getPhysicalAddressKernel(service->pagingInfo.pageDirectory);
     runTask->esp = malloc(0x1000);
     runTask->respondingTo = respondingTo;
     runTask->service = service;
     memset(runTask->esp, 0, 0x1000);
-    runTask->esp += 0xFFC;
-    *(void **)runTask->esp = &runEnd;
+    runTask->esp += 0xFF8;
+    *(void **)runTask->esp = provider->address;
+    *(void **)(runTask->esp + 4) = &runEnd;
     sharePage(&service->pagingInfo, runTask->esp, runTask->esp);
     listAdd(&callsToProcess, runTask);
-    if (!runTask->address) {
-        asm("hlt" ::"a"(runTask), "b"(provider), "c"(service), "d"(elfData));
-    }
     return runTask;
 }
 
@@ -68,8 +65,6 @@
         call->resume = true;
         if (!call->avoidReschedule) {
             listAdd(&callsToProcess, call);
-            void *temporary = mapTemporary(call->writeBack);
-            memcpy(call, temporary, sizeof(IOPortInSyscall));
         }
     }
 }
diff --git a/src/kernel/memory/malloc.c b/src/kernel/memory/malloc.c
index e715905..c6aa5f9 100644
--- a/src/kernel/memory/malloc.c
+++ b/src/kernel/memory/malloc.c
@@ -15,7 +15,9 @@
         block->allocatedCoarse &= ~(1 << coarse);
         break;
     }
-    return ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    void *result = ((uint8_t *)block) + block->blockSize * (32 * coarse + fine);
+    memset(result, 0, block->blockSize);
+    return result;
 }
 
 void *malloc(uint32_t size) {
diff --git a/src/kernel/service/service.asm b/src/kernel/service/service.asm
index f538328..9c47365 100644
--- a/src/kernel/service/service.asm
+++ b/src/kernel/service/service.asm
@@ -2,7 +2,7 @@
 
 global runFunction
 global runEnd
-global runEndSyscall
+global temporaryESP
 
 extern currentSyscall
 
@@ -13,17 +13,17 @@
   mov eax, esp
   mov [temporaryESP], eax
   mov ebx, [currentSyscall]
-  mov ecx, [ebx + 8]
+  mov ecx, [ebx + 24]
   mov ebp, ecx
-  mov edx, [ebx + 4]
-  mov eax, [ebx + 12]
+  mov edx, returnPoint
+  mov eax, [ebx + 28]
+  mov ebx, [ebx + 20]
   mov cr3, eax
+  mov eax, ebx
   sysexit
 runEnd:
   mov eax, 0
   sysenter
-runEndSyscall:
-  mov eax, [temporaryESP]
-  mov esp, eax
-  pop ebp
+
+returnPoint:
   ret
diff --git a/src/kernel/service/services.c b/src/kernel/service/services.c
index 450b4b2..a61ff1d 100644
--- a/src/kernel/service/services.c
+++ b/src/kernel/service/services.c
@@ -13,9 +13,6 @@
 
 void resume(Syscall *syscall) {
     currentSyscall = syscall;
-    if (!syscall->address) {
-        asm("hlt" ::"a"(syscall));
-    }
     runFunction();
 }
 
diff --git a/src/kernel/syscalls/syscall.c b/src/kernel/syscalls/syscall.c
index 51dd4c4..541cea0 100644
--- a/src/kernel/syscalls/syscall.c
+++ b/src/kernel/syscalls/syscall.c
@@ -5,7 +5,6 @@
 #include <syscalls.h>
 #include <util.h>
 
-extern void *runEndSyscall;
 extern ListElement *callsToProcess;
 extern void(syscallStub)();
 extern Syscall *currentSyscall;
@@ -19,30 +18,30 @@
           0); // when transitioning to 64 bit: U32(value) >> 32);
 }
 
-void handleSyscall(void *cr3, Syscall *callData) {
-    if (!callData) {
+void handleSyscall(void *esp, uint32_t function, uint32_t parameter0,
+                   uint32_t parameter1, uint32_t parameter2,
+                   uint32_t parameter3) {
+    if (!function) {
         if (currentSyscall->respondingTo) {
             listAdd(&callsToProcess, currentSyscall->respondingTo);
         }
-        asm("jmp runEndSyscall");
+        return;
     }
-    Service *service = currentSyscall->service;
-    void *dataPhysical =
-        getPhysicalAddress(service->pagingInfo.pageDirectory, callData);
-    Syscall *call = malloc(sizeof(RequestSyscall));
-    void *data = mapTemporary(dataPhysical);
-    memcpy(data, call, sizeof(RequestSyscall));
-    call->cr3 = cr3;
+    Syscall *call = malloc(sizeof(Syscall));
+    call->function = function;
+    call->parameters[0] = parameter0;
+    call->parameters[1] = parameter1;
+    call->parameters[2] = parameter2;
+    call->parameters[3] = parameter3;
     call->service = currentSyscall->service;
-    call->writeBack = dataPhysical;
+    call->esp = esp;
     if (!call->respondingTo) {
         call->respondingTo = currentSyscall->respondingTo;
     }
-    if (!call->address) {
-        asm("hlt" ::"a"(call), "b"(dataPhysical));
-    }
+    Service *currentService = currentSyscall->service;
+    call->cr3 =
+        getPhysicalAddressKernel(currentService->pagingInfo.pageDirectory);
     listAdd(&callsToProcess, call);
-    asm("jmp runEndSyscall");
 }
 
 void *syscallStubPtr = syscallStub;
@@ -53,28 +52,33 @@
     writeMsrRegister(0x176, syscallStubPtr);          // the handler
 }
 
-void handleInstallSyscall(RegisterServiceProviderSyscall *call) {
+void handleInstallSyscall(Syscall *call) {
     Provider *provider = malloc(sizeof(Provider));
     Service *service = call->service;
-    char *providerName = kernelMapPhysical(
-        getPhysicalAddress(service->pagingInfo.pageDirectory, call->name));
+    char *providerName = kernelMapPhysical(getPhysicalAddress(
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     provider->name = providerName;
-    provider->address = call->handler;
+    provider->address = PTR(call->parameters[1]);
     provider->service = call->service;
     listAdd(&service->providers, provider);
 }
 
-void handleRequestSyscall(RequestSyscall *call) {
+void *listGet(ListElement *list, uint32_t position) {
+    for (uint32_t i = 0; i < position; i++) {
+        list = list->next;
+    }
+    return list->data;
+}
+
+extern ListElement *services;
+
+void handleRequestSyscall(Syscall *call) {
     Service *service = call->service;
-    char *serviceName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->serviceName));
-    Service *providerService = findService(serviceName);
-    char *providerName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->providerName));
-    Provider *callProvider = findProvider(providerService, providerName);
+    Service *providerService = listGet(services, call->parameters[0]);
+    Provider *provider =
+        listGet(providerService->providers, call->parameters[1]);
     Syscall *runCall = malloc(sizeof(Syscall));
     runCall->function = SYS_RUN;
-    runCall->address = callProvider->address;
     runCall->esp = malloc(0x1000);
     runCall->respondingTo = (void *)call;
     runCall->cr3 =
@@ -82,50 +86,94 @@
     runCall->service = providerService;
     runCall->resume = true;
     sharePage(&providerService->pagingInfo, runCall->esp, runCall->esp);
-    runCall->esp += 0xFFC;
-    *(void **)runCall->esp = &runEnd;
+    runCall->esp += 0xFF8;
+    *(void **)runCall->esp = provider->address;
+    *(void **)(runCall->esp + 4) = &runEnd;
     listAdd(&callsToProcess, runCall);
     call->avoidReschedule = true;
 }
 
-void handleIOInSyscall(IOPortInSyscall *call) {
-    switch (call->size) {
+void handleIOInSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("in %%dx, %%al" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%al"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 2:
-        asm("in %%dx, %%ax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%ax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     case 4:
-        asm("in %%dx, %%eax" : "=a"(call->result) : "d"(call->port));
+        asm("in %%dx, %%eax"
+            : "=a"(call->returnValue)
+            : "d"(call->parameters[1]));
         break;
     }
 }
 
-void handleIOOutSyscall(IOPortOutSyscall *call) {
-    switch (call->size) {
+void handleIOOutSyscall(Syscall *call) {
+    switch (call->parameters[0]) {
     case 1:
-        asm("out %0, %1" : : "a"((uint8_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint8_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 2:
-        asm("out %0, %1" : : "a"((uint16_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint16_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     case 4:
-        asm("out %0, %1" : : "a"((uint32_t)call->value), "Nd"(call->port));
+        asm("out %0, %1"
+            :
+            : "a"((uint32_t)call->parameters[2]), "Nd"(call->parameters[1]));
         break;
     }
 }
 
 extern Syscall *loadInitrdProgram(char *name, Syscall *respondingTo);
 
-void handleLoadFromInitrdSyscall(LoadFromInitrdSyscall *call) {
+void handleLoadFromInitrdSyscall(Syscall *call) {
     Service *service = call->service;
     char *programName = kernelMapPhysical(getPhysicalAddress(
-        service->pagingInfo.pageDirectory, call->programName));
+        service->pagingInfo.pageDirectory, PTR(call->parameters[0])));
     loadInitrdProgram(programName, (void *)call);
     call->avoidReschedule = true;
 }
 
+void handleGetServiceSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[0])));
+    foreach (services, Service *, service, {
+        if (stringEquals(service->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
+void handleGetProviderSyscall(Syscall *call) {
+    uint32_t i = 0;
+    Service *callService = call->service;
+    char *name = kernelMapPhysical(getPhysicalAddress(
+        callService->pagingInfo.pageDirectory, PTR(call->parameters[1])));
+    Service *providerService = listGet(services, call->parameters[0]);
+    foreach (providerService->providers, Provider *, provider, {
+        if (stringEquals(provider->name, name)) {
+            call->returnValue = i;
+            return;
+        }
+        i++;
+    })
+        ;
+}
+
 void (*syscallHandlers[])(Syscall *) = {
     0,
     (void *)handleInstallSyscall,
@@ -133,4 +181,6 @@
     (void *)handleIOInSyscall,
     (void *)handleIOOutSyscall,
     (void *)handleLoadFromInitrdSyscall,
+    (void *)handleGetServiceSyscall,
+    (void *)handleGetProviderSyscall,
 };
diff --git a/src/kernel/syscalls/syscallStub.asm b/src/kernel/syscalls/syscallStub.asm
index ad29d6e..f8213a8 100644
--- a/src/kernel/syscalls/syscallStub.asm
+++ b/src/kernel/syscalls/syscallStub.asm
@@ -3,16 +3,23 @@
 
 global syscallStub
 extern handleSyscall
+extern temporaryESP
+
+temporaryEAX: resb 4
 
 syscallStub:
-  mov ebx, cr3
-  mov ecx, 0x500000
-  mov cr3, ecx
-  push eax
+  mov [temporaryEAX], eax
+  mov eax, 0x500000
+  mov cr3, eax
+  mov eax, [temporaryEAX]
+  push esi
+  push edx
+  push ecx
   push ebx
+  push eax
+  push edi
   call handleSyscall
-  pop ebx
-  mov edx, [eax+4]
-  mov ecx, [eax+8]
-  mov cr3, ebx
-  sysexit
+  mov eax, [temporaryESP]
+  mov esp, eax
+  pop ebp
+  ret
diff --git a/src/kernel/util/list.c b/src/kernel/util/list.c
index aa04956..a5f39fb 100644
--- a/src/kernel/util/list.c
+++ b/src/kernel/util/list.c
@@ -3,9 +3,17 @@
 
 void listAdd(ListElement **list, void *data) {
     ListElement *element = malloc(sizeof(ListElement));
-    element->next = *list;
     element->data = data;
-    *list = element;
+    element->next = NULL;
+    if (!*list) {
+        *list = element;
+        return;
+    }
+    ListElement *current = *list;
+    while (current->next) {
+        current = current->next;
+    }
+    current->next = element;
 }
 
 void *listPopFirst(ListElement **list) {
diff --git a/src/userland/loader/main.c b/src/userland/loader/main.c
index 3a6f72e..271647b 100644
--- a/src/userland/loader/main.c
+++ b/src/userland/loader/main.c
@@ -1,45 +1,30 @@
 #include <stdint.h>
 #include <syscalls.h>
 
-void syscall(void *callData) {
-    Syscall *call = callData;
-    call->respondingTo = 0;
-    call->resume = false;
-    asm("mov %%ebp, %%eax" : "=a"(call->esp));
-    call->address = &&returnAddress;
-    asm("sysenter\n" ::"a"(callData));
-returnAddress:
-    asm("nop");
-    return;
+#define PTR(x) ((void *)(uintptr_t)x)
+#define U32(x) ((uint32_t)(uintptr_t)x)
+
+uint32_t syscall(uint32_t function, uint32_t parameter0, uint32_t parameter1,
+                 uint32_t parameter2, uint32_t parameter3) {
+    uint32_t esp, result;
+    asm("push %%eax" ::"a"(&&end));
+    asm("mov %%esp, %%eax" : "=a"(esp));
+    asm("sysenter\n"
+        :
+        : "a"(function), "b"(parameter0), "c"(parameter1), "d"(parameter2),
+          "S"(parameter3), "D"(esp));
+end:
+    // eax is set by the kernel as the return value
+    asm("nop" : "=a"(result));
+    return result;
 }
 
-void makeRequest(char *moduleName, char *functionName, void *data,
-                 uint32_t size) {
-    RequestSyscall call = {
-        .function = SYS_REQUEST,
-        .serviceName = moduleName,
-        .providerName = functionName,
-        .data = data,
-        .dataSize = size,
-    };
-    syscall(&call);
+void request(uint32_t module, uint32_t function, void *data, uint32_t size) {
+    syscall(SYS_REQUEST, module, function, U32(data), size);
 }
 
 void installServiceProvider(char *name, void(provider)(void *)) {
-    RegisterServiceProviderSyscall call = {
-        .function = SYS_REGISTER_FUNCTION,
-        .name = name,
-        .handler = provider,
-    };
-    syscall(&call);
-}
-
-void loadFromInitrd(char *name) {
-    LoadFromInitrdSyscall call = {
-        .function = SYS_LOAD_INITRD,
-        .programName = name,
-    };
-    syscall(&call);
+    syscall(SYS_REGISTER_FUNCTION, U32(name), U32(provider), 0, 0);
 }
 
 uint32_t strlen(char *string) {
@@ -51,7 +36,23 @@
     return size;
 }
 
-void log(char *message) { makeRequest("log", "log", message, strlen(message)); }
+uint32_t getModule(char *name) {
+    return syscall(SYS_GET_SERVICE, U32(name), strlen(name), 0, 0);
+}
+
+uint32_t getProvider(uint32_t module, char *name) {
+    return syscall(SYS_GET_PROVIDER, module, U32(name), strlen(name), 0);
+}
+
+void loadFromInitrd(char *name) {
+    syscall(SYS_LOAD_INITRD, U32(name), strlen(name), 0, 0);
+}
+
+void log(char *message) {
+    uint32_t module = getModule("log");
+    uint32_t provider = getProvider(module, "log");
+    request(module, provider, message, strlen(message));
+}
 
 int32_t main() {
     loadFromInitrd("log");
diff --git a/src/userland/log/main.c b/src/userland/log/main.c
index 46827ae..e2a95b1 100644
--- a/src/userland/log/main.c
+++ b/src/userland/log/main.c
@@ -1,36 +1,43 @@
 #include <stdint.h>
 #include <syscalls.h>
 
-void syscall(void *callData) {
-    Syscall *call = callData;
-    call->respondingTo = 0;
-    call->resume = false;
-    asm("mov %%ebp, %%eax" : "=a"(call->esp));
-    call->address = &&returnAddress;
-    asm("sysenter\n" ::"a"(callData));
-returnAddress:
-    asm("nop");
-    return;
+#define PTR(x) ((void *)(uintptr_t)x)
+#define U32(x) ((uint32_t)(uintptr_t)x)
+
+uint32_t syscall(uint32_t function, uint32_t parameter0, uint32_t parameter1,
+                 uint32_t parameter2, uint32_t parameter3) {
+    uint32_t esp, result;
+    asm("push %%eax" ::"a"(&&end));
+    asm("mov %%esp, %%eax" : "=a"(esp));
+    asm("sysenter\n"
+        :
+        : "a"(function), "b"(parameter0), "c"(parameter1), "d"(parameter2),
+          "S"(parameter3), "D"(esp));
+// eax is set by the kernel as the return value
+end:
+    asm("nop" : "=a"(result));
+    return result;
+}
+
+void installServiceProvider(char *name, void(provider)(void *)) {
+    syscall(SYS_REGISTER_FUNCTION, U32(name), U32(provider), 0, 0);
+}
+
+uint32_t strlen(char *string) {
+    uint32_t size = 0;
+    while (*string) {
+        string++;
+        size++;
+    }
+    return size;
 }
 
 uint32_t ioIn(uint16_t port, uint8_t size) {
-    IOPortInSyscall call = {
-        .function = SYS_IO_IN,
-        .port = port,
-        .size = size,
-    };
-    syscall(&call);
-    return call.result;
+    return syscall(SYS_IO_IN, size, port, 0, 0);
 }
 
 void ioOut(uint16_t port, uint32_t value, uint8_t size) {
-    IOPortOutSyscall call = {
-        .function = SYS_IO_OUT,
-        .port = port,
-        .value = value,
-        .size = size,
-    };
-    syscall(&call);
+    syscall(SYS_IO_OUT, size, port, value, 0);
 }
 
 void writeParallel(uint8_t data) {
@@ -52,25 +59,6 @@
     writeParallel('g');
 }
 
-void makeRequest(char *moduleName, char *functionName) {
-    RequestSyscall call = {
-        .function = SYS_REQUEST,
-        .serviceName = moduleName,
-        .providerName = functionName,
-        .data = 0,
-    };
-    syscall(&call);
-}
-
-void installServiceProvider(char *name, void(provider)(void *)) {
-    RegisterServiceProviderSyscall call = {
-        .function = SYS_REGISTER_FUNCTION,
-        .name = name,
-        .handler = provider,
-    };
-    syscall(&call);
-}
-
 int32_t main() {
     installServiceProvider("log", log);
     writeParallel('m');