| /kernel/trunk/arch/amd64/src/syscall.c |
|---|
| 34,6 → 34,7 |
| #include <arch/asm.h> |
| #include <print.h> |
| #include <arch/cpu.h> |
| extern void syscall_entry(void); |
| 54,17 → 55,19 |
| | ((__u64)(gdtselector(KTEXT_DES) | PL_KERNEL)<<32)); |
| write_msr(AMD_MSR_LSTAR, (__u64)syscall_entry); |
| /* Mask RFLAGS on syscall |
| * - we do not care what is in the flags field |
| * - disable interrupts, until we exchange the stack register |
| * (mask the IE bit) |
| */ |
| write_msr(AMD_MSR_SFMASK, 0); |
| write_msr(AMD_MSR_SFMASK, 0x200); |
| } |
| /** Dispatch system call */ |
| __native syscall_handler(__native id, __native a1, __native a2, __native a3) |
| { |
| interrupts_enable(); |
| if (id < SYSCALL_END) |
| return syscall_table[id](a1,a2,a3); |
| else |
| panic("Undefined syscall %d", id); |
| interrupts_disable(); |
| } |
| /kernel/trunk/arch/amd64/src/asm_utils.S |
|---|
| 192,10 → 192,29 |
| syscall_entry: |
| # TODO: Switch to kernel stack |
| # Switch to hidden gs |
| swapgs |
| # TODO: I would like LEA instead of thes 2 instrs, |
| # why does not it work??? |
| mov %gs:0, %r10 # We have a stack in r10 |
| addq $0x0ff0, %r10 |
| movq %rsp, 0(%r10) # Save old stack pointer to stack |
| movq %r10, %rsp # Change to new stack |
| pushq %rcx # Return address |
| pushq %r11 # Save flags |
| # Switch back to remain consistent |
| swapgs |
| movq %r9, %rcx # Exchange last parameter as a third |
| call syscall_handler |
| # Switch back |
| sysret |
| popq %r11 |
| popq %rcx |
| movq 0(%rsp), %rsp |
| sysretq |
| .data |
| .global interrupt_handler_size |
| /kernel/trunk/arch/amd64/src/proc/scheduler.c |
|---|
| 31,8 → 31,15 |
| #include <proc/thread.h> |
| #include <arch.h> |
| #include <arch/context.h> /* SP_DELTA */ |
| #include <arch/asm.h> |
| void before_thread_runs_arch(void) |
| { |
| CPU->arch.tss->rsp0 = (__address) &THREAD->kstack[THREAD_STACK_SIZE-SP_DELTA]; |
| /* Syscall support - write thread address to hidden part of gs */ |
| swapgs(); |
| write_msr(AMD_MSR_GS, |
| (__u64)&THREAD->kstack); |
| swapgs(); |
| } |