[mirror_ubuntu-bionic-kernel.git] / drivers / s390 / char / tape_class.c

// SPDX-License-Identifier: GPL-2.0
/*
 * 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;

	rc = cdev_add(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);
Commit	Line	Data
6f05e69e	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
a53c8fab	3	* Copyright IBM Corp. 2004
1da177e4 LT	4	*
	5	* Tape class device support
	6	*
	7	* Author: Stefan Bader <shbader@de.ibm.com>
	8	* Based on simple class device code by Greg K-H
	9	*/
bb509912 MH	10
	11	#define KMSG_COMPONENT "tape"
	12	#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
	13
5a0e3ad6 TH	14	#include <linux/slab.h>
5a0e3ad6 TH	15
1da177e4 LT	16	#include "tape_class.h"
	17
	18	MODULE_AUTHOR("Stefan Bader <shbader@de.ibm.com>");
	19	MODULE_DESCRIPTION(
a53c8fab	20	"Copyright IBM Corp. 2004 All Rights Reserved.\n"
e018ba1f	21	"tape_class.c"
1da177e4 LT	22	);
	23	MODULE_LICENSE("GPL");
	24
56b22935	25	static struct class *tape_class;
1da177e4 LT	26
	27	/*
	28	* Register a tape device and return a pointer to the cdev structure.
	29	*
	30	* device
	31	* The pointer to the struct device of the physical (base) device.
	32	* drivername
	33	* The pointer to the drivers name for it's character devices.
	34	* dev
	35	* The intended major/minor number. The major number may be 0 to
	36	* get a dynamic major number.
	37	* fops
	38	* The pointer to the drivers file operations for the tape device.
	39	* devname
	40	* The pointer to the name of the character device.
	41	*/
	42	struct tape_class_device *register_tape_dev(
	43	struct device * device,
	44	dev_t dev,
9c2e08c5	45	const struct file_operations *fops,
1da177e4 LT	46	char * device_name,
	47	char * mode_name)
	48	{
	49	struct tape_class_device * tcd;
	50	int rc;
	51	char * s;
	52
88abaab4	53	tcd = kzalloc(sizeof(struct tape_class_device), GFP_KERNEL);
1da177e4 LT	54	if (!tcd)
	55	return ERR_PTR(-ENOMEM);
	56
1da177e4 LT	57	strncpy(tcd->device_name, device_name, TAPECLASS_NAME_LEN);
	58	for (s = strchr(tcd->device_name, '/'); s; s = strchr(s, '/'))
	59	*s = '!';
	60	strncpy(tcd->mode_name, mode_name, TAPECLASS_NAME_LEN);
	61	for (s = strchr(tcd->mode_name, '/'); s; s = strchr(s, '/'))
	62	*s = '!';
	63
	64	tcd->char_device = cdev_alloc();
	65	if (!tcd->char_device) {
	66	rc = -ENOMEM;
	67	goto fail_with_tcd;
	68	}
	69
	70	tcd->char_device->owner = fops->owner;
	71	tcd->char_device->ops = fops;
1da177e4	72
b08e19de	73	rc = cdev_add(tcd->char_device, dev, 1);
1da177e4 LT	74	if (rc)
	75	goto fail_with_cdev;
	76
ea9e42f6 GKH	77	tcd->class_device = device_create(tape_class, device,
	78	tcd->char_device->dev, NULL,
	79	"%s", tcd->device_name);
4bdb613f	80	rc = PTR_RET(tcd->class_device);
d7cf0d57 HC	81	if (rc)
	82	goto fail_with_cdev;
	83	rc = sysfs_create_link(
1da177e4 LT	84	&device->kobj,
	85	&tcd->class_device->kobj,
	86	tcd->mode_name
	87	);
d7cf0d57 HC	88	if (rc)
d7cf0d57 HC	89	goto fail_with_class_device;
1da177e4 LT	90
	91	return tcd;
	92
d7cf0d57	93	fail_with_class_device:
7f021ce1	94	device_destroy(tape_class, tcd->char_device->dev);
d7cf0d57	95
1da177e4 LT	96	fail_with_cdev:
	97	cdev_del(tcd->char_device);
	98
	99	fail_with_tcd:
	100	kfree(tcd);
	101
	102	return ERR_PTR(rc);
	103	}
	104	EXPORT_SYMBOL(register_tape_dev);
	105
92bf435f	106	void unregister_tape_dev(struct device device, struct tape_class_device tcd)
1da177e4 LT	107	{
1da177e4 LT	108	if (tcd != NULL && !IS_ERR(tcd)) {
92bf435f	109	sysfs_remove_link(&device->kobj, tcd->mode_name);
7f021ce1	110	device_destroy(tape_class, tcd->char_device->dev);
1da177e4 LT	111	cdev_del(tcd->char_device);
	112	kfree(tcd);
	113	}
	114	}
	115	EXPORT_SYMBOL(unregister_tape_dev);
	116
	117
	118	static int __init tape_init(void)
	119	{
56b22935	120	tape_class = class_create(THIS_MODULE, "tape390");
1da177e4 LT	121
	122	return 0;
	123	}
	124
	125	static void __exit tape_exit(void)
	126	{
56b22935	127	class_destroy(tape_class);
1da177e4 LT	128	tape_class = NULL;
	129	}
	130
	131	postcore_initcall(tape_init);
	132	module_exit(tape_exit);