Suspend process waiting for keyboard input

kernel/device/ps2_kb.c

@@ -7,6 +7,7 @@
 #include <m/status.h>
 #include <proc/capability.h>
 #include <proc/proc.h>
+#include <proc/suspension_q.h>
 #include <sync/spin_lock.h>
 #include <sys/debug.h>
 #include <sys/smp.h>
@@ -41,6 +42,7 @@
 
 static struct ringbuffer ps2kb_ringbuffer;
 static spin_lock_t ps2kb_ringbuffer_lock = SPIN_LOCK_INIT;
+static struct proc_suspension_q ps2kb_sq;
 
 static uint8_t shiftcode[0x100] = {
     [0x1d] = KB_CTL, [0x2a] = KB_SHIFT, [0x36] = KB_SHIFT,
@@ -161,35 +163,61 @@ int32_t ps2kb_keycode (void) {
   return c;
 }
 
-void ps2kb_irq (void* arg, void* regs) {
+bool ps2kb_irq (struct cpu** reschedule_cpu, void* arg, void* regs) {
   int32_t keycode = ps2kb_keycode ();
 
-  if (keycode >= 0) {
-    spin_lock (&ps2kb_ringbuffer_lock);
-    ringbuffer_push (uint8_t, &ps2kb_ringbuffer, (uint8_t)keycode);
+  if (keycode <= 0)
+    return PROC_NO_RESCHEDULE;
+
+  spin_lock (&ps2kb_ringbuffer_lock);
+  spin_lock (&ps2kb_sq.lock);
+
+  ringbuffer_push (uint8_t, &ps2kb_ringbuffer, (uint8_t)keycode);
+
+  struct list_node_link* node = ps2kb_sq.proc_list;
+
+  if (node) {
+    struct proc_sq_entry* sq_entry = list_entry (node, struct proc_sq_entry, sq_link);
+    struct proc* resumed_proc = sq_entry->proc;
+
+    spin_unlock (&ps2kb_sq.lock);
     spin_unlock (&ps2kb_ringbuffer_lock);
+
+    return proc_sq_resume (resumed_proc, sq_entry, reschedule_cpu);
   }
+
+  spin_unlock (&ps2kb_sq.lock);
+  spin_unlock (&ps2kb_ringbuffer_lock);
+
+  return PROC_NO_RESCHEDULE;
 }
 
-int ps2kb_read_key (struct proc* proc, void* a1, void* a2, void* a3, void* a4) {
-  if (!(proc->procgroup->capabilities & PROC_CAP_KB))
-    return -ST_PERMISSION_ERROR;
+bool ps2kb_read_key (struct proc* proc, struct cpu** reschedule_cpu, int* ret, void* a1, void* a2,
+                     void* a3, void* a4) {
+  if (!(proc->procgroup->capabilities & PROC_CAP_KB)) {
+    *ret = -ST_PERMISSION_ERROR;
+    return PROC_NO_RESCHEDULE;
+  }
 
   uint8_t* chbuf = (uint8_t*)a1;
 
   spin_lock (&ps2kb_ringbuffer_lock);
 
   size_t prev_count = ps2kb_ringbuffer.count;
+
   ringbuffer_pop (uint8_t, &ps2kb_ringbuffer, chbuf);
+
   size_t new_count = ps2kb_ringbuffer.count;
 
-  spin_unlock (&ps2kb_ringbuffer_lock);
+  *ret = ST_OK;
 
   /* didn't pop anything */
   if (prev_count == new_count)
-    return -ST_TRY_AGAIN;
+    return proc_sq_suspend (proc, &ps2kb_sq, &ps2kb_ringbuffer_lock, reschedule_cpu);
 
-  return ST_OK;
+  spin_unlock (&ps2kb_ringbuffer_lock);
+
+  return PROC_NO_RESCHEDULE;
 }
 
 bool ps2kb_init (void* arg) {