diff options
Diffstat (limited to 'src/kernel')
| -rw-r--r-- | src/kernel/arch/generic.h | 2 | ||||
| -rw-r--r-- | src/kernel/arch/i386/sysenter.s | 9 | ||||
| -rw-r--r-- | src/kernel/syscalls.c | 11 |
3 files changed, 20 insertions, 2 deletions
diff --git a/src/kernel/arch/generic.h b/src/kernel/arch/generic.h index 08f26a7..0b005a2 100644 --- a/src/kernel/arch/generic.h +++ b/src/kernel/arch/generic.h @@ -17,7 +17,7 @@ void halt_cpu(); // src/arch/i386/sysenter.s void sysexit(void (*fun)(), void *stack_top); void sysenter_setup(); -void syscall_handler(); +int syscall_handler(int, int, int, int); // all of those can allocate memory struct pagedir *pagedir_new(); diff --git a/src/kernel/arch/i386/sysenter.s b/src/kernel/arch/i386/sysenter.s index 3fcd4c3..7375e06 100644 --- a/src/kernel/arch/i386/sysenter.s +++ b/src/kernel/arch/i386/sysenter.s @@ -49,6 +49,10 @@ sysenter_setup: sysenter_handler: pushal + push %edi + push %esi + push %ebx + push %eax mov %cr0, %eax and $0x7FFFFFFF, %eax // disable paging @@ -56,9 +60,14 @@ sysenter_handler: call syscall_handler + // save the return value + mov %eax, 44(%esp) // 16 [top of eflags] + 7*4 [skip until EAX] + mov %edx, 32(%esp) // 16 + 4*4 [skip until EBX] + mov %cr0, %eax or $0x80000000, %eax // enable paging mov %eax, %cr0 + add $16, %esp popal sysexit diff --git a/src/kernel/syscalls.c b/src/kernel/syscalls.c index 25b8eb5..a42dc44 100644 --- a/src/kernel/syscalls.c +++ b/src/kernel/syscalls.c @@ -1,6 +1,15 @@ #include <kernel/arch/generic.h> #include <kernel/panic.h> -void syscall_handler() { +int syscall_handler(int a, int b, int c, int d) { + // verify that the parameters get passed correctly + if (a != 1) panic(); + if (b != 2) panic(); + if (c != 3) panic(); + if (d != 4) panic(); + log_const("in a syscall!"); + + // used to check if the return value gets passed correctly + return 0x4e; } |