Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / s390 / char / tape_class.c

diff --git a/kernel/drivers/s390/char/tape_class.c b/kernel/drivers/s390/char/tape_class.c
new file mode 100644 (file)
index 0000000..91c3c64
--- /dev/null
+++ b/kernel/drivers/s390/char/tape_class.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright IBM Corp. 2004
+ *
+ * Tape class device support
+ *
+ * Author: Stefan Bader <shbader@de.ibm.com>
+ * Based on simple class device code by Greg K-H
+ */
+
+#define KMSG_COMPONENT "tape"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/slab.h>
+
+#include "tape_class.h"
+
+MODULE_AUTHOR("Stefan Bader <shbader@de.ibm.com>");
+MODULE_DESCRIPTION(
+       "Copyright IBM Corp. 2004   All Rights Reserved.\n"
+       "tape_class.c"
+);
+MODULE_LICENSE("GPL");
+
+static struct class *tape_class;
+
+/*
+ * Register a tape device and return a pointer to the cdev structure.
+ *
+ * device
+ *     The pointer to the struct device of the physical (base) device.
+ * drivername
+ *     The pointer to the drivers name for it's character devices.
+ * dev
+ *     The intended major/minor number. The major number may be 0 to
+ *     get a dynamic major number.
+ * fops
+ *     The pointer to the drivers file operations for the tape device.
+ * devname
+ *     The pointer to the name of the character device.
+ */
+struct tape_class_device *register_tape_dev(
+       struct device *         device,
+       dev_t                   dev,
+       const struct file_operations *fops,
+       char *                  device_name,
+       char *                  mode_name)
+{
+       struct tape_class_device *      tcd;
+       int             rc;
+       char *          s;
+
+       tcd = kzalloc(sizeof(struct tape_class_device), GFP_KERNEL);
+       if (!tcd)
+               return ERR_PTR(-ENOMEM);
+
+       strncpy(tcd->device_name, device_name, TAPECLASS_NAME_LEN);
+       for (s = strchr(tcd->device_name, '/'); s; s = strchr(s, '/'))
+               *s = '!';
+       strncpy(tcd->mode_name, mode_name, TAPECLASS_NAME_LEN);
+       for (s = strchr(tcd->mode_name, '/'); s; s = strchr(s, '/'))
+               *s = '!';
+
+       tcd->char_device = cdev_alloc();
+       if (!tcd->char_device) {
+               rc = -ENOMEM;
+               goto fail_with_tcd;
+       }
+
+       tcd->char_device->owner = fops->owner;
+       tcd->char_device->ops   = fops;
+       tcd->char_device->dev   = dev;
+
+       rc = cdev_add(tcd->char_device, tcd->char_device->dev, 1);
+       if (rc)
+               goto fail_with_cdev;
+
+       tcd->class_device = device_create(tape_class, device,
+                                         tcd->char_device->dev, NULL,
+                                         "%s", tcd->device_name);
+       rc = PTR_RET(tcd->class_device);
+       if (rc)
+               goto fail_with_cdev;
+       rc = sysfs_create_link(
+               &device->kobj,
+               &tcd->class_device->kobj,
+               tcd->mode_name
+       );
+       if (rc)
+               goto fail_with_class_device;
+
+       return tcd;
+
+fail_with_class_device:
+       device_destroy(tape_class, tcd->char_device->dev);
+
+fail_with_cdev:
+       cdev_del(tcd->char_device);
+
+fail_with_tcd:
+       kfree(tcd);
+
+       return ERR_PTR(rc);
+}
+EXPORT_SYMBOL(register_tape_dev);
+
+void unregister_tape_dev(struct device *device, struct tape_class_device *tcd)
+{
+       if (tcd != NULL && !IS_ERR(tcd)) {
+               sysfs_remove_link(&device->kobj, tcd->mode_name);
+               device_destroy(tape_class, tcd->char_device->dev);
+               cdev_del(tcd->char_device);
+               kfree(tcd);
+       }
+}
+EXPORT_SYMBOL(unregister_tape_dev);
+
+
+static int __init tape_init(void)
+{
+       tape_class = class_create(THIS_MODULE, "tape390");
+
+       return 0;
+}
+
+static void __exit tape_exit(void)
+{
+       class_destroy(tape_class);
+       tape_class = NULL;
+}
+
+postcore_initcall(tape_init);
+module_exit(tape_exit);