Task2

module2/Makefile

@@ -0,0 +1,9 @@
+obj-m += counter.o
+
+ABS_PATH_TO_VROOT ?= ../initramfs
+PATH_TO_MODULE_BUILD=$(ABS_PATH_TO_VROOT)/lib/modules/6.7.4/build
+
+all:
+	make -C "$(PATH_TO_MODULE_BUILD)" M="$(PWD)" modules
+clean:
+	make -C "$(PATH_TO_MODULE_BUILD)" M="$(PWD)" clean

module2/compile.sh

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+cp -r ../module2 ../../ || exit
+cd ../../module2 || exit
+make clean || exit
+make all || exit
+cp counter.ko ../initramfs/lib/modules/6.7.4/ || exit
+cd ../initramfs || exit
+find . | cpio -ov --format=newc | gzip -9 > ../try/initramfs.gz || exit
+cd ..
+# cleanup
+rm -r module2
+rm initramfs/lib/modules/6.7.4/counter.ko

module2/counter.c

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+//
+// Created by mikhail on 21.05.24.
+//
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+
+MODULE_LICENSE("MIT");
+MODULE_AUTHOR("Me");
+MODULE_DESCRIPTION("Key press counter");
+
+// Counter
+
+static atomic_t press_count = ATOMIC_INIT(0);
+
+irqreturn_t irq_handler(int irq, void* dev_id) {
+  atomic_inc(&press_count);
+  return IRQ_NONE;
+}
+
+static struct timer_list timer;
+
+// Timer callback
+
+static void reschedule_timer(void) {
+  mod_timer(&timer, jiffies + msecs_to_jiffies(60000));
+}
+
+void callback(struct timer_list* _) {
+  int number = atomic_read(&press_count);
+  pr_info("Characters typed: %d\n", number);
+  reschedule_timer();
+}
+
+// Module funcs
+
+static int __init counter_init(void) {
+  timer_setup(&timer, callback, 0);
+  reschedule_timer();
+  int err = request_irq(1, // PS/2 irq
+                        irq_handler,
+                        IRQF_SHARED,
+                        "Key counter",
+                        (void*) irq_handler);
+  if (err) {
+    del_timer(&timer);
+    pr_err("request_irq failed with errcode %d\n.", err);
+    return err;
+  }
+  return 0;
+}
+
+static void __exit counter_exit(void) {
+  free_irq(1, (void*) irq_handler);
+  del_timer(&timer);
+}
+
+module_init(counter_init);
+module_exit(counter_exit);