arch/cortex-m: Updated the UserspaceKernelBoundary implementation

Signed-off-by: Ioan-Cristian CÎRSTEA <ioan.cirstea@oxidos.io>

Author: IoanCristianCirstea

arch/cortex-m/src/syscall.rs

@@ -16,8 +16,6 @@ use kernel::errorcode::ErrorCode;
 use kernel::memory_management::pointers::{
     ImmutableKernelVirtualPointer,
     ImmutableUserVirtualPointer,
-    MutableKernelVirtualPointer,
-    MutableUserVirtualPointer,
 };
 
 use crate::CortexMVariant;
@@ -170,18 +168,10 @@ impl<A: CortexMVariant> kernel::syscall::UserspaceKernelBoundary for SysCall<A>
         Ok(())
     }
 
-    fn get_sp(&self, state: &mut Self::StoredState) -> MutableUserVirtualPointer<u8> {
-        // SAFETY: `esp` is a valid user pointer
-        unsafe { MutableUserVirtualPointer::new_from_raw(state.psp as *mut u8) }.unwrap()
-    }
-
     unsafe fn set_syscall_return_value(
         &self,
-        _kernel_accessible_memory_start: &ImmutableKernelVirtualPointer<u8>,
-        _kernel_app_brk: &ImmutableKernelVirtualPointer<u8>,
         user_accessible_memory_start: &ImmutableUserVirtualPointer<u8>,
         user_app_brk: &ImmutableUserVirtualPointer<u8>,
-        _sp: &MutableKernelVirtualPointer<u8>,
         state: &mut Self::StoredState,
         return_value: kernel::syscall::SyscallReturn,
     ) -> Result<(), ()> {
@@ -248,11 +238,8 @@ impl<A: CortexMVariant> kernel::syscall::UserspaceKernelBoundary for SysCall<A>
     /// In effect, this converts `svc` into `bl callback`.
     unsafe fn set_process_function(
         &self,
-        _kernel_accessible_memory_start: &ImmutableKernelVirtualPointer<u8>,
-        _kernel_app_brk: &ImmutableKernelVirtualPointer<u8>,
         user_accessible_memory_start: &ImmutableUserVirtualPointer<u8>,
         user_app_brk: &ImmutableUserVirtualPointer<u8>,
-        _sp: &MutableKernelVirtualPointer<u8>,
         state: &mut CortexMStoredState,
         callback: kernel::process::FunctionCall,
     ) -> Result<(), ()> {
@@ -284,11 +271,8 @@ impl<A: CortexMVariant> kernel::syscall::UserspaceKernelBoundary for SysCall<A>
 
     unsafe fn switch_to_process(
         &self,
-        _kernel_accessible_memory_start: &ImmutableKernelVirtualPointer<u8>,
-        _kernel_app_brk: &ImmutableKernelVirtualPointer<u8>,
         user_accessible_memory_start: &ImmutableUserVirtualPointer<u8>,
         user_app_brk: &ImmutableUserVirtualPointer<u8>,
-        _sp: &MutableKernelVirtualPointer<u8>,
         state: &mut CortexMStoredState,
     ) -> (kernel::syscall::ContextSwitchReason, Option<ImmutableUserVirtualPointer<u8>>) {
         let user_accessible_memory_start_address = user_accessible_memory_start.get_address();