summaryrefslogtreecommitdiff
path: root/drivers/s390/block/dasd_cmb.c
blob: 4f365bff275c7881472ad1173bf01b1cc2bcd633 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/*
 * linux/drivers/s390/block/dasd_cmb.c ($Revision: 1.9 $)
 *
 * Linux on zSeries Channel Measurement Facility support
 *  (dasd device driver interface)
 *
 * Copyright 2000,2003 IBM Corporation
 *
 * Author: Arnd Bergmann <arndb@de.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <asm/ccwdev.h>
#include <asm/cmb.h>

#include "dasd_int.h"

static int
dasd_ioctl_cmf_enable(struct block_device *bdev, int no, long args)
{
	struct dasd_device *device;

	device = bdev->bd_disk->private_data;
	if (!device)
		return -EINVAL;

	return enable_cmf(device->cdev);
}

static int
dasd_ioctl_cmf_disable(struct block_device *bdev, int no, long args)
{
	struct dasd_device *device;

	device = bdev->bd_disk->private_data;
	if (!device)
		return -EINVAL;

	return disable_cmf(device->cdev);
}

static int
dasd_ioctl_readall_cmb(struct block_device *bdev, int no, long args)
{
	struct dasd_device *device;
	struct cmbdata __user *udata;
	struct cmbdata data;
	size_t size;
	int ret;

	device = bdev->bd_disk->private_data;
	if (!device)
		return -EINVAL;
	udata = (void __user *) args;
	size = _IOC_SIZE(no);

	if (!access_ok(VERIFY_WRITE, udata, size))
		return -EFAULT;
	ret = cmf_readall(device->cdev, &data);
	if (ret)
		return ret;
	if (copy_to_user(udata, &data, min(size, sizeof(*udata))))
		return -EFAULT;
	return 0;
}

/* module initialization below here. dasd already provides a mechanism
 * to dynamically register ioctl functions, so we simply use this. */
static inline int
ioctl_reg(unsigned int no, dasd_ioctl_fn_t handler)
{
	return dasd_ioctl_no_register(THIS_MODULE, no, handler);
}

static inline void
ioctl_unreg(unsigned int no, dasd_ioctl_fn_t handler)
{
	dasd_ioctl_no_unregister(THIS_MODULE, no, handler);
}

static void
dasd_cmf_exit(void)
{
	ioctl_unreg(BIODASDCMFENABLE,  dasd_ioctl_cmf_enable);
	ioctl_unreg(BIODASDCMFDISABLE, dasd_ioctl_cmf_disable);
	ioctl_unreg(BIODASDREADALLCMB, dasd_ioctl_readall_cmb);
}

static int __init
dasd_cmf_init(void)
{
	int ret;
	ret = ioctl_reg (BIODASDCMFENABLE, dasd_ioctl_cmf_enable);
	if (ret)
		goto err;
	ret = ioctl_reg (BIODASDCMFDISABLE, dasd_ioctl_cmf_disable);
	if (ret)
		goto err;
	ret = ioctl_reg (BIODASDREADALLCMB, dasd_ioctl_readall_cmb);
	if (ret)
		goto err;

	return 0;
err:
	dasd_cmf_exit();

	return ret;
}

module_init(dasd_cmf_init);
module_exit(dasd_cmf_exit);

MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("channel measurement facility interface for dasd\n"
		   "Copyright 2003 IBM Corporation\n");