Merge branch 'feat_inital_context_switching' into 'develop_ba'

Implement Context Switching

See merge request teachos/kernel!6

1 files changed, 35 insertions, 0 deletions

diff --git a/arch/x86_64/src/context_switching/syscall/main.cpp b/arch/x86_64/src/context_switching/syscall/main.cpp
new file mode 100644
index 0000000..e291c10
--- /dev/null
+++ b/arch/x86_64/src/context_switching/syscall/main.cpp
@@ -0,0 +1,35 @@
+#include "arch/context_switching/syscall/main.hpp"
+
+namespace teachos::arch::context_switching::syscall
+{
+  auto syscall(type syscall_number, arguments args) -> response
+  {
+    asm volatile("mov %[input], %%rax"
+                 : /* no output from call */
+                 : [input] "m"(syscall_number)
+                 : "memory");
+
+    asm volatile("mov %[input], %%rdi " : /* no output from call */ : [input] "m"(args.arg_0) : "memory");
+    asm volatile("mov %[input], %%rsi" : /* no output from call */ : [input] "m"(args.arg_1) : "memory");
+    asm volatile("mov %[input], %%rdx" : /* no output from call */ : [input] "m"(args.arg_2) : "memory");
+    asm volatile("mov %[input], %%r10" : /* no output from call */ : [input] "m"(args.arg_3) : "memory");
+    asm volatile("mov %[input], %%r8" : /* no output from call */ : [input] "m"(args.arg_4) : "memory");
+    asm volatile("mov %[input], %%r9" : /* no output from call */ : [input] "m"(args.arg_5) : "memory");
+
+    asm volatile("syscall");
+
+    arguments values{};
+    asm volatile("mov %%rdi, %[output]" : [output] "=m"(values.arg_0));
+    asm volatile("mov %%rsi, %[output]" : [output] "=m"(values.arg_1));
+    asm volatile("mov %%rdx, %[output]" : [output] "=m"(values.arg_2));
+    asm volatile("mov %%r10, %[output]" : [output] "=m"(values.arg_3));
+    asm volatile("mov %%r8, %[output]" : [output] "=m"(values.arg_4));
+    asm volatile("mov %%r9, %[output]" : [output] "=m"(values.arg_5));
+
+    error error_code{};
+    asm volatile("mov %%rax, %[output]" : [output] "=m"(error_code));
+
+    return {error_code, values};
+  }
+
+}  // namespace teachos::arch::context_switching::syscall