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#include "arch/x86_64/processor.h"
#include "syscall/handles.h"
#include "print.h"
#include "lock.h"
#include "error.h"
#include <stddef.h>

static inline int
s_invoke_release(
        objdir_t *root_dir, 
        objdir_entry_t *target, 
        uint8_t *payload, 
        size_t payload_at,
        int (*invoke)(objdir_t*, objdir_entry_t*, uint8_t*, size_t))
{
    int e = invoke(root_dir, target, payload, payload_at);
    mtx_release(&target->lock);
    return e;
}

int 
_syscall_handler_arch(objdir_t *root_dir, objdir_entry_t *target, uint8_t *payload, size_t payload_at)
{
    switch(target->type) {
        case KO_MEMORY_MAPPING:
            return s_invoke_release(root_dir, target, payload, payload_at, syscall_handle_invoke_mapping);
        default:
            klogf("Missing implementation of invoke for type %i\n", target->type);
            mtx_release(&target->lock);
            return -KE_BADTYPE;
    }
}

__attribute__((naked))
void _syscall_entry(void)
{
    __asm__ volatile(" \
            pushq %%r11; \
            pushq %%rcx; \
            swapgs; \
            movq %%gs:%c[tcb], %%rax; \
            movq %%rsp, %c[sp](%%rax); \
            movq %c[ksp](%%rax), %%rsp; \
            pushq %c[sp](%%rax); \
            callq _syscall_handler; \
            swapgs; \
            popq %%rsp; \
            popq %%rcx; \
            popq %%r11; \
            sysretq;"
            ::
            [tcb] "i"(offsetof(processor_t, tcb)),
            [sp] "i"(offsetof(tcb_t, sp)),
            [ksp] "i"(offsetof(tcb_t, ksp)));
}