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Diffstat (limited to 'arch/x86_64/src/kernel/cpu/segment_register.cpp')
-rw-r--r--arch/x86_64/src/kernel/cpu/segment_register.cpp98
1 files changed, 0 insertions, 98 deletions
diff --git a/arch/x86_64/src/kernel/cpu/segment_register.cpp b/arch/x86_64/src/kernel/cpu/segment_register.cpp
deleted file mode 100644
index b08c9c4..0000000
--- a/arch/x86_64/src/kernel/cpu/segment_register.cpp
+++ /dev/null
@@ -1,98 +0,0 @@
-#include "arch/kernel/cpu/segment_register.hpp"
-
-#include "arch/context_switching/interrupt_descriptor_table/segment_selector.hpp"
-#include "arch/exception_handling/assert.hpp"
-
-namespace teachos::arch::kernel::cpu
-{
- auto reload_data_segment_registers() -> void
- {
- asm volatile("xor %%rax, %%rax\n"
- "mov %%rax, %%ss\n"
- "mov %%rax, %%ds\n"
- "mov %%rax, %%es\n"
- "mov %%rax, %%fs\n"
- "mov %%rax, %%gs\n"
- : /* no output from call */
- : /* no input to call */
- : "rax");
- }
-
- auto set_data_segment_registers(context_switching::interrupt_descriptor_table::segment_selector data_segment) -> void
- {
- asm volatile("xor %%rax, %%rax\n"
- "mov %[input], %%ax\n"
- "mov %%rax, %%ds\n"
- "mov %%rax, %%es\n"
- "mov %%rax, %%fs\n"
- "mov %%rax, %%gs\n"
- : /* no output from call */
- : [input] "m"(data_segment)
- : "rax");
- }
-
- auto read_code_segment_register() -> context_switching::interrupt_descriptor_table::segment_selector
- {
- context_switching::interrupt_descriptor_table::segment_selector current_value{};
- asm volatile("mov %%cs, %[output]" : [output] "=r"(current_value));
- return current_value;
- }
-
- auto validate_data_segment_registers(context_switching::interrupt_descriptor_table::segment_selector data_segment)
- -> void
- {
- context_switching::interrupt_descriptor_table::segment_selector ss{};
- context_switching::interrupt_descriptor_table::segment_selector ds{};
- context_switching::interrupt_descriptor_table::segment_selector es{};
- context_switching::interrupt_descriptor_table::segment_selector fs{};
- context_switching::interrupt_descriptor_table::segment_selector gs{};
-
- asm volatile(
- "mov %%ss, %[ss_output]\n"
- "mov %%ds, %[ds_output]\n"
- "mov %%es, %[es_output]\n"
- "mov %%fs, %[fs_output]\n"
- "mov %%gs, %[gs_output]\n"
- : [ss_output] "=r"(ss), [ds_output] "=r"(ds), [es_output] "=r"(es), [fs_output] "=r"(fs), [gs_output] "=r"(gs));
-
- auto result = (ss == ds && ss == es && ss == fs && ss == gs);
- exception_handling::assert(result, "[Segment Register] Values in data register are not the same.");
- result = (ss == data_segment);
- exception_handling::assert(
- result, "[Segment Register] Expected Data Segment is not the same as the value in the Stack Segment register.");
- }
-
- auto validate_code_segment_register(context_switching::interrupt_descriptor_table::segment_selector code_segment)
- -> void
- {
- auto const cs = read_code_segment_register();
- exception_handling::assert(
- cs == code_segment,
- "[Segment Register] Expected Code Segment is not the same as the value in the Code Segment register.");
- }
-
- auto validate_segment_registers(context_switching::interrupt_descriptor_table::segment_selector data_segment,
- context_switching::interrupt_descriptor_table::segment_selector code_segment) -> void
- {
- validate_data_segment_registers(data_segment);
- validate_code_segment_register(code_segment);
- }
-
- auto set_code_segment_register(context_switching::interrupt_descriptor_table::segment_selector data_segment,
- context_switching::interrupt_descriptor_table::segment_selector code_segment,
- uint64_t address) -> void
- {
- asm volatile("mov %%rsp, %%rax\n"
- "push %[data_segment]\n"
- "push %%rax\n"
- "pushfq\n"
- "push %[code_segment]\n"
- "mov %[return_function], %%rax\n"
- "push %%rax\n"
- "iretq\n"
- : /* no output from call */
- : [data_segment] "m"(data_segment), [code_segment] "m"(code_segment), [return_function] "r"(address)
- : "rax");
- }
-
-} // namespace teachos::arch::kernel::cpu