Modularize interrupt handlers, split up scheduler and PIT interrupt handlers

kernel/dev/ps2kbdev.c

@@ -8,6 +8,7 @@
 #include "proc/proc.h"
 #include "io/io.h"
 #include "ipc/mbus/mbus.h"
+#include "intr/intr.h"
 #include "errors.h"
 #include "hshtb.h"
 #include "kprintf.h"
@@ -155,12 +156,16 @@ int32_t ps2kb_intr(void) {
 
 IpcMBus *PS2KB_MBUS;
 
-void ps2kbdev_intr(void) {
+int ps2kbdev_intr(IntrStackFrame *frame) {
+  (void)frame;
+
   int32_t c = ps2kb_intr();
   if (c >= 0) {
     uint8_t b = c;
     ipc_mbuspublish("ps2kb", &b);
   }
+
+  return INTR_OK;
 }
 
 void ps2kbdev_init(void) {

kernel/intr/intr.c

@@ -19,17 +19,39 @@
 
 typedef struct IntrHandler {
   struct IntrHandler *next;
-  void (*fn)(void);
+  int (*fn)(IntrStackFrame *frame);
   int irq;
 } IntrHandler;
 
 IntrHandler *INTR_HANDLERS = NULL;
+SpinLock INTR_HANDLERS_SPINLOCK;
 
-void intr_attchhandler(void (*fn)(void), int irq) {
+void intr_attchhandler(int (*fn)(IntrStackFrame *frame), int irq) {
   IntrHandler *ih = dlmalloc(sizeof(*ih));
   ih->fn = fn;
   ih->irq = irq;
+  spinlock_acquire(&INTR_HANDLERS_SPINLOCK);
   LL_APPEND(INTR_HANDLERS, ih);
+  spinlock_release(&INTR_HANDLERS_SPINLOCK);
+}
+
+int32_t intr_dttchhandler(int irq) {
+  IntrHandler *ih = NULL;
+
+  spinlock_acquire(&INTR_HANDLERS_SPINLOCK);
+
+  LL_FINDPROP(INTR_HANDLERS, ih, irq, irq);
+
+  if (ih == NULL) {
+    spinlock_release(&INTR_HANDLERS_SPINLOCK);
+    return E_NOENTRY;
+  }
+
+  LL_REMOVE(INTR_HANDLERS, ih);
+  spinlock_release(&INTR_HANDLERS_SPINLOCK);
+
+  dlfree(ih);
+  return E_OK;
 }
 
 typedef struct BackTraceFrame {
@@ -104,6 +126,8 @@ static const char *exceptions[] = {
 };
 
 void intr_init(void) {
+  spinlock_init(&INTR_HANDLERS_SPINLOCK);
+
   #define MKINTR(N) \
     extern void intr_vec##N(void); \
     idt_setentry(N, (uint64_t)&intr_vec##N, 0x8E);
@@ -222,22 +246,16 @@ void intr_handleintr(IntrStackFrame *frame) {
       cpu_hang();
     }
   } else if (frame->trapnum >= 32 && frame->trapnum <= 47) {
-    switch (frame->trapnum) {
+    bool send = true;
-      case INTR_IRQBASE+0:
-        PIT_TICKS++;
-        intr_pic_eoi();
-        proc_sched((void *)frame);
-        break;
-      default:
     IntrHandler *ih, *ihtmp;
     LL_FOREACH_SAFE(INTR_HANDLERS, ih, ihtmp) {
       if ((uint64_t)ih->irq == frame->trapnum) {
-            ih->fn();
+        if (ih->fn(frame) == INTR_NOEOI) {
+          send = false;
         }
       }
-        intr_pic_eoi();
-        break;
     }
+    if (send) intr_pic_eoi();
   } else if (frame->trapnum == 0x80) {
     intr_syscalldispatch(frame);
   }

kernel/intr/intr.h

@@ -2,10 +2,14 @@
 #define INTR_INTR_H_
 
 #include <stdint.h>
+#include <stdbool.h>
 #include "compiler/attr.h"
 
 #define INTR_IRQBASE 0x20
 
+#define INTR_OK     1
+#define INTR_NOEOI  2
+
 typedef struct {
   uint64_t r15;
   uint64_t r14;
@@ -34,7 +38,8 @@ typedef struct {
   uint64_t ss;
 } PACKED IntrStackFrame;
 
-void intr_attchhandler(void (*fn)(void), int irq);
+void intr_attchhandler(int (*fn)(IntrStackFrame *frame), int irq);
+int32_t intr_dttchhandler(int irq);
 void intr_disable(void);
 void intr_enable(void);
 void intr_init(void);

kernel/intr/pit.c

@@ -1,6 +1,7 @@
 #include <stdint.h>
 #include "intr/pit.h"
 #include "io/io.h"
+#include "intr/intr.h"
 
 #define PIT_COUNTER0      0x40
 #define PIT_CMD           0x43
@@ -25,15 +26,22 @@
 
 volatile uint32_t PIT_TICKS;
 
+void intr_pit_wait(uint32_t ms) {
+  uint32_t now = PIT_TICKS;
+  while (PIT_TICKS - now < ms);
+}
+
+int intr_pit_intr(IntrStackFrame *frame) {
+  PIT_TICKS++;
+  return INTR_OK;
+}
+
 void intr_pit_init(void) {
+  intr_attchhandler(&intr_pit_intr, INTR_IRQBASE+0);
+
   uint32_t hz = 1000;
   uint32_t div = PIT_FREQ / hz;
   io_out8(PIT_CMD, PIT_CMD_BINARY | PIT_CMD_MODE3 | PIT_CMD_RW_BOTH | PIT_CMD_COUNTER0);
   io_out8(PIT_COUNTER0, div & 0xFF);
   io_out8(PIT_COUNTER0, div >> 8);
 }
-
-void intr_pit_wait(uint32_t ms) {
-  uint32_t now = PIT_TICKS;
-  while (PIT_TICKS - now < ms);
-}

kernel/kmain.c

@@ -45,9 +45,9 @@ void kmain(void) {
   log_bootinfo();
   log_time();
   gdt_init();
-  intr_init();
   pmm_init();
   vmm_init();
+  intr_init();
   randcrypto_init();
   ipc_mbusinit();
   dev_init();

kernel/proc/proc.c

@@ -16,8 +16,9 @@
 #include "std/string.h"
 #include "cpu/gdt.h"
 #include "intr/intr.h"
-#include "switch.h"
+#include "intr/pic.h"
 #include "vmm/vmm.h"
+#include "proc/switch.h"
 #include "elf.h"
 #include "errors.h"
 #include "kprintf.h"
@@ -252,10 +253,18 @@ void proc_killself(void) {
   proc_kill(proc);
 }
 
+int proc_intr(IntrStackFrame *frame) {
+  intr_pic_eoi();
+  proc_sched(frame);
+  return INTR_NOEOI;
+}
+
 void proc_init(void) {
   spinlock_init(&PROCS.spinlock);
   PROCS.procs = NULL;
 
+  intr_attchhandler(&proc_intr, INTR_IRQBASE+0);
+
   Proc *init = proc_spawnuser("base", "/bin/init");
   PROCS.current = init;
   proc_register(init);