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
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
|
/*
* File...........: linux/drivers/s390/block/dasd_genhd.c
* Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
* Horst Hummel <Horst.Hummel@de.ibm.com>
* Carsten Otte <Cotte@de.ibm.com>
* Martin Schwidefsky <schwidefsky@de.ibm.com>
* Bugreports.to..: <Linux390@de.ibm.com>
* (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
*
* gendisk related functions for the dasd driver.
*
* $Revision: 1.51 $
*/
#include <linux/config.h>
#include <linux/interrupt.h>
#include <linux/fs.h>
#include <linux/blkpg.h>
#include <asm/uaccess.h>
/* This is ugly... */
#define PRINTK_HEADER "dasd_gendisk:"
#include "dasd_int.h"
/*
* Allocate and register gendisk structure for device.
*/
int
dasd_gendisk_alloc(struct dasd_device *device)
{
struct gendisk *gdp;
int len;
/* Make sure the minor for this device exists. */
if (device->devindex >= DASD_PER_MAJOR)
return -EBUSY;
gdp = alloc_disk(1 << DASD_PARTN_BITS);
if (!gdp)
return -ENOMEM;
/* Initialize gendisk structure. */
gdp->major = DASD_MAJOR;
gdp->first_minor = device->devindex << DASD_PARTN_BITS;
gdp->fops = &dasd_device_operations;
gdp->driverfs_dev = &device->cdev->dev;
/*
* Set device name.
* dasda - dasdz : 26 devices
* dasdaa - dasdzz : 676 devices, added up = 702
* dasdaaa - dasdzzz : 17576 devices, added up = 18278
* dasdaaaa - dasdzzzz : 456976 devices, added up = 475252
*/
len = sprintf(gdp->disk_name, "dasd");
if (device->devindex > 25) {
if (device->devindex > 701) {
if (device->devindex > 18277)
len += sprintf(gdp->disk_name + len, "%c",
'a'+(((device->devindex-18278)
/17576)%26));
len += sprintf(gdp->disk_name + len, "%c",
'a'+(((device->devindex-702)/676)%26));
}
len += sprintf(gdp->disk_name + len, "%c",
'a'+(((device->devindex-26)/26)%26));
}
len += sprintf(gdp->disk_name + len, "%c", 'a'+(device->devindex%26));
sprintf(gdp->devfs_name, "dasd/%s", device->cdev->dev.bus_id);
if (device->features & DASD_FEATURE_READONLY)
set_disk_ro(gdp, 1);
gdp->private_data = device;
gdp->queue = device->request_queue;
device->gdp = gdp;
set_capacity(device->gdp, 0);
add_disk(device->gdp);
return 0;
}
/*
* Unregister and free gendisk structure for device.
*/
void
dasd_gendisk_free(struct dasd_device *device)
{
del_gendisk(device->gdp);
device->gdp->queue = 0;
put_disk(device->gdp);
device->gdp = 0;
}
/*
* Trigger a partition detection.
*/
int
dasd_scan_partitions(struct dasd_device * device)
{
struct block_device *bdev;
/* Make the disk known. */
set_capacity(device->gdp, device->blocks << device->s2b_shift);
bdev = bdget_disk(device->gdp, 0);
if (!bdev || blkdev_get(bdev, FMODE_READ, 1) < 0)
return -ENODEV;
/*
* See fs/partition/check.c:register_disk,rescan_partitions
* Can't call rescan_partitions directly. Use ioctl.
*/
ioctl_by_bdev(bdev, BLKRRPART, 0);
/*
* Since the matching blkdev_put call to the blkdev_get in
* this function is not called before dasd_destroy_partitions
* the offline open_count limit needs to be increased from
* 0 to 1. This is done by setting device->bdev (see
* dasd_generic_set_offline). As long as the partition
* detection is running no offline should be allowed. That
* is why the assignment to device->bdev is done AFTER
* the BLKRRPART ioctl.
*/
device->bdev = bdev;
return 0;
}
/*
* Remove all inodes in the system for a device, delete the
* partitions and make device unusable by setting its size to zero.
*/
void
dasd_destroy_partitions(struct dasd_device * device)
{
/* The two structs have 168/176 byte on 31/64 bit. */
struct blkpg_partition bpart;
struct blkpg_ioctl_arg barg;
struct block_device *bdev;
/*
* Get the bdev pointer from the device structure and clear
* device->bdev to lower the offline open_count limit again.
*/
bdev = device->bdev;
device->bdev = 0;
/*
* See fs/partition/check.c:delete_partition
* Can't call delete_partitions directly. Use ioctl.
* The ioctl also does locking and invalidation.
*/
memset(&bpart, 0, sizeof(struct blkpg_partition));
memset(&barg, 0, sizeof(struct blkpg_ioctl_arg));
barg.data = &bpart;
barg.op = BLKPG_DEL_PARTITION;
for (bpart.pno = device->gdp->minors - 1; bpart.pno > 0; bpart.pno--)
ioctl_by_bdev(bdev, BLKPG, (unsigned long) &barg);
invalidate_partition(device->gdp, 0);
/* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
blkdev_put(bdev);
set_capacity(device->gdp, 0);
}
int
dasd_gendisk_init(void)
{
int rc;
/* Register to static dasd major 94 */
rc = register_blkdev(DASD_MAJOR, "dasd");
if (rc != 0) {
MESSAGE(KERN_WARNING,
"Couldn't register successfully to "
"major no %d", DASD_MAJOR);
return rc;
}
return 0;
}
void
dasd_gendisk_exit(void)
{
unregister_blkdev(DASD_MAJOR, "dasd");
}
|
