1 files changed, 35 insertions, 5 deletions
diff --git a/src/kernel/idt.c b/src/kernel/idt.c
index 31d597f..3d23797 100644
--- a/src/kernel/idt.c
+++ b/src/kernel/idt.c
@@ -6,6 +6,7 @@
 #include "panic.h"
 #include "task.h"
 #include "paging.h"
+#include "pmap.h"
 
 enum {
   IDT_PRESENT = 0x80,
@@ -73,6 +74,32 @@ static void *sc_allocate_ram(uint32_t pages) {
   return pd_user_allocate_anywhere_writable(active_task->page_directory, pages);
 }
 
+enum mi_arg {
+  MI_KERNEL_MAX,
+  MI_KERNEL_LEFT,
+  MI_USER_MAX,
+  MI_USER_LEFT,
+  MI_TASK_LEFT
+};
+
+__attribute__ ((pure))
+static uint32_t sc_memory_info(enum mi_arg arg) {
+  switch (arg) {
+  case MI_KERNEL_MAX:
+    return max_kernel_pages;
+  case MI_KERNEL_LEFT:
+    return kernel_pages_left;
+  case MI_USER_MAX:
+    return max_user_pages;
+  case MI_USER_LEFT:
+    return user_pages_left;
+  case MI_TASK_LEFT:
+    panic("TODO: this process memory left");
+  default:
+    return -1;
+  }
+}
+
 void const *syscall_table[] = {
   &sc_open_file,
   &sc_close_file,
@@ -81,14 +108,17 @@ void const *syscall_table[] = {
   &sc_start_task,
   &sc_log_string,
   &sc_get_key,
-  &sc_allocate_ram
+  &sc_allocate_ram,
+  &sc_memory_info
 };
 
-extern void syscall_isr;
-extern void quit_isr;
-extern void yield_isr;
+typedef void isr_t;
+
+extern isr_t syscall_isr;
+extern isr_t quit_isr;
+extern isr_t yield_isr;
 
-static void register_int(uint8_t n, void *isr, uint8_t dpl) {
+static void register_int(uint8_t n, isr_t *isr, uint8_t dpl) {
   idt[n].addr_low = (uint32_t)isr & 0xffff;
   idt[n].addr_high = (uint32_t)isr >> 16;
   idt[n].cs = 0x10;