|
@@ -0,0 +1,157 @@
|
|
|
+#include <linux/init.h>
|
|
|
+#include <linux/module.h>
|
|
|
+#include <linux/device.h>
|
|
|
+#include <linux/types.h>
|
|
|
+#include <linux/cdev.h>
|
|
|
+#include <linux/fs.h>
|
|
|
+#include <linux/slab.h>
|
|
|
+
|
|
|
+
|
|
|
+#include "mod.h"
|
|
|
+#include "dev.h"
|
|
|
+#include "debug.h"
|
|
|
+
|
|
|
+
|
|
|
+MODULE_LICENSE("GPL v2");
|
|
|
+MODULE_AUTHOR("Suren A. Chilingaryan <csa@suren.me>");
|
|
|
+MODULE_DESCRIPTION("Kernel Memory Manager - a module to manipulate kernel memory");
|
|
|
+MODULE_VERSION("0.0.1");
|
|
|
+
|
|
|
+int kmm_minors = KMM_MINORS;
|
|
|
+
|
|
|
+module_param(kmm_minors, int, S_IRUGO);
|
|
|
+
|
|
|
+
|
|
|
+static dev_t kmm_devno; /**< major number */
|
|
|
+static kmm_dev_t **kmm_devs = NULL; /**< per-device context */
|
|
|
+static spinlock_t kmm_devs_lock; /**< lock protecting creation/destruction of devices */
|
|
|
+static struct class *kmm_class; /**< device class */
|
|
|
+
|
|
|
+
|
|
|
+static void kmm_module_cleanup(void)
|
|
|
+{
|
|
|
+ int i;
|
|
|
+
|
|
|
+ if (kmm_devs) {
|
|
|
+ for (i = 0; i < kmm_minors; i++) {
|
|
|
+ if (kmm_devs[i]) {
|
|
|
+ if (kmm_devs[i]->dev)
|
|
|
+ device_destroy(kmm_class, kmm_devs[i]->devno);
|
|
|
+ cdev_del(&kmm_devs[i]->cdev);
|
|
|
+ kfree(kmm_devs[i]);
|
|
|
+ }
|
|
|
+ }
|
|
|
+ kfree(kmm_devs);
|
|
|
+ }
|
|
|
+
|
|
|
+
|
|
|
+ if (kmm_class)
|
|
|
+ class_destroy(kmm_class);
|
|
|
+
|
|
|
+ unregister_chrdev_region(kmm_devno, kmm_minors);
|
|
|
+}
|
|
|
+
|
|
|
+static int kmm_module_setup_cdev(void)
|
|
|
+{
|
|
|
+ int i;
|
|
|
+ int err = 0;
|
|
|
+ dev_t devno;
|
|
|
+ kmm_dev_t *dev;
|
|
|
+
|
|
|
+ dev = kmalloc(sizeof(kmm_dev_t), GFP_KERNEL);
|
|
|
+ if (!dev) {
|
|
|
+ mod_info("Couldn't allocate memory. Device is not created.\n");
|
|
|
+ return -ENOMEM;
|
|
|
+ }
|
|
|
+
|
|
|
+ cdev_init(&dev->cdev, kmm_get_fops());
|
|
|
+ dev->cdev.owner = THIS_MODULE;
|
|
|
+ dev->cdev.ops = kmm_get_fops();
|
|
|
+
|
|
|
+ spin_lock(&kmm_devs_lock);
|
|
|
+ for (i = 0; i < kmm_minors; i++) {
|
|
|
+ if (!kmm_devs[i])
|
|
|
+ break;
|
|
|
+ }
|
|
|
+
|
|
|
+ if (i == kmm_minors) {
|
|
|
+ mod_info("No free minor numbers left");
|
|
|
+ err = -EBUSY;
|
|
|
+ goto fail;
|
|
|
+ }
|
|
|
+
|
|
|
+ devno = MKDEV(MAJOR(kmm_devno), MINOR(kmm_devno) + i);
|
|
|
+ dev->devno = devno;
|
|
|
+
|
|
|
+ err = cdev_add(&dev->cdev, devno, 1);
|
|
|
+ if (err) {
|
|
|
+ mod_info("Error %d adding device kmm%d", err, i);
|
|
|
+ goto fail;
|
|
|
+ }
|
|
|
+
|
|
|
+ dev->dev = device_create(kmm_class, NULL, devno, dev, KMM_NODE_FMT, MINOR(kmm_devno) + i);
|
|
|
+ if (!dev->dev) {
|
|
|
+ mod_info("Error creating /dev/%s%d\n", KMM_NODE, MINOR(kmm_devno) + i);
|
|
|
+ goto fail;
|
|
|
+ }
|
|
|
+ dev_set_drvdata(dev->dev, dev);
|
|
|
+
|
|
|
+ kmm_devs[i] = dev;
|
|
|
+ spin_unlock(&kmm_devs_lock);
|
|
|
+
|
|
|
+ mod_info("Device /dev/%s%d added\n", KMM_NODE, MINOR(kmm_devno) + i);
|
|
|
+
|
|
|
+ return 0;
|
|
|
+
|
|
|
+fail:
|
|
|
+ spin_unlock(&kmm_devs_lock);
|
|
|
+ kfree(dev);
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+static int __init kmm_module_init(void)
|
|
|
+{
|
|
|
+ int err;
|
|
|
+
|
|
|
+ spin_lock_init(&kmm_devs_lock);
|
|
|
+
|
|
|
+ if ((err = alloc_chrdev_region(&kmm_devno, 0, kmm_minors, KMM_NODE))) {
|
|
|
+ mod_info("Couldn't allocate chrdev region. Module not loaded.\n");
|
|
|
+ goto alloc_chrdev_fail;
|
|
|
+ }
|
|
|
+
|
|
|
+ kmm_class = class_create(THIS_MODULE, KMM_NODE);
|
|
|
+ if (IS_ERR(kmm_class)) {
|
|
|
+ mod_info("No sysfs support. Module not loaded.\n");
|
|
|
+ goto fail;
|
|
|
+ }
|
|
|
+
|
|
|
+ kmm_devs = kmalloc(kmm_minors * sizeof(kmm_dev_t*), GFP_KERNEL);
|
|
|
+ if (!kmm_devs) {
|
|
|
+ mod_info("Couldn't allocate memory. Module not loaded.\n");
|
|
|
+ err = -ENOMEM;
|
|
|
+ }
|
|
|
+ memset(kmm_devs, 0, kmm_minors * sizeof(kmm_dev_t*));
|
|
|
+
|
|
|
+ mod_info("Major %d allocated to node '%s'\n", MAJOR(kmm_devno), KMM_NODE);
|
|
|
+
|
|
|
+ err = kmm_module_setup_cdev();
|
|
|
+ if (err) goto fail;
|
|
|
+
|
|
|
+
|
|
|
+ return 0;
|
|
|
+
|
|
|
+fail:
|
|
|
+ kmm_module_cleanup();
|
|
|
+alloc_chrdev_fail:
|
|
|
+ return err;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+static void __exit kmm_module_exit(void)
|
|
|
+{
|
|
|
+ kmm_module_cleanup();
|
|
|
+}
|
|
|
+
|
|
|
+module_init(kmm_module_init);
|
|
|
+module_exit(kmm_module_exit);
|