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Diffstat (limited to 'drivers/s390/block/dasd_genhd.c')
-rw-r--r--drivers/s390/block/dasd_genhd.c185
1 files changed, 185 insertions, 0 deletions
diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
new file mode 100644
index 000000000000..1d52db406b2e
--- /dev/null
+++ b/drivers/s390/block/dasd_genhd.c
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1/*
2 * File...........: linux/drivers/s390/block/dasd_genhd.c
3 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4 * Horst Hummel <Horst.Hummel@de.ibm.com>
5 * Carsten Otte <Cotte@de.ibm.com>
6 * Martin Schwidefsky <schwidefsky@de.ibm.com>
7 * Bugreports.to..: <Linux390@de.ibm.com>
8 * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
9 *
10 * gendisk related functions for the dasd driver.
11 *
12 * $Revision: 1.48 $
13 */
14
15#include <linux/config.h>
16#include <linux/interrupt.h>
17#include <linux/fs.h>
18#include <linux/blkpg.h>
19
20#include <asm/uaccess.h>
21
22/* This is ugly... */
23#define PRINTK_HEADER "dasd_gendisk:"
24
25#include "dasd_int.h"
26
27/*
28 * Allocate and register gendisk structure for device.
29 */
30int
31dasd_gendisk_alloc(struct dasd_device *device)
32{
33 struct gendisk *gdp;
34 int len;
35
36 /* Make sure the minor for this device exists. */
37 if (device->devindex >= DASD_PER_MAJOR)
38 return -EBUSY;
39
40 gdp = alloc_disk(1 << DASD_PARTN_BITS);
41 if (!gdp)
42 return -ENOMEM;
43
44 /* Initialize gendisk structure. */
45 gdp->major = DASD_MAJOR;
46 gdp->first_minor = device->devindex << DASD_PARTN_BITS;
47 gdp->fops = &dasd_device_operations;
48 gdp->driverfs_dev = &device->cdev->dev;
49
50 /*
51 * Set device name.
52 * dasda - dasdz : 26 devices
53 * dasdaa - dasdzz : 676 devices, added up = 702
54 * dasdaaa - dasdzzz : 17576 devices, added up = 18278
55 * dasdaaaa - dasdzzzz : 456976 devices, added up = 475252
56 */
57 len = sprintf(gdp->disk_name, "dasd");
58 if (device->devindex > 25) {
59 if (device->devindex > 701) {
60 if (device->devindex > 18277)
61 len += sprintf(gdp->disk_name + len, "%c",
62 'a'+(((device->devindex-18278)
63 /17576)%26));
64 len += sprintf(gdp->disk_name + len, "%c",
65 'a'+(((device->devindex-702)/676)%26));
66 }
67 len += sprintf(gdp->disk_name + len, "%c",
68 'a'+(((device->devindex-26)/26)%26));
69 }
70 len += sprintf(gdp->disk_name + len, "%c", 'a'+(device->devindex%26));
71
72 sprintf(gdp->devfs_name, "dasd/%s", device->cdev->dev.bus_id);
73
74 if (test_bit(DASD_FLAG_RO, &device->flags))
75 set_disk_ro(gdp, 1);
76 gdp->private_data = device;
77 gdp->queue = device->request_queue;
78 device->gdp = gdp;
79 set_capacity(device->gdp, 0);
80 add_disk(device->gdp);
81 return 0;
82}
83
84/*
85 * Unregister and free gendisk structure for device.
86 */
87void
88dasd_gendisk_free(struct dasd_device *device)
89{
90 del_gendisk(device->gdp);
91 device->gdp->queue = 0;
92 put_disk(device->gdp);
93 device->gdp = 0;
94}
95
96/*
97 * Trigger a partition detection.
98 */
99int
100dasd_scan_partitions(struct dasd_device * device)
101{
102 struct block_device *bdev;
103
104 /* Make the disk known. */
105 set_capacity(device->gdp, device->blocks << device->s2b_shift);
106 bdev = bdget_disk(device->gdp, 0);
107 if (!bdev || blkdev_get(bdev, FMODE_READ, 1) < 0)
108 return -ENODEV;
109 /*
110 * See fs/partition/check.c:register_disk,rescan_partitions
111 * Can't call rescan_partitions directly. Use ioctl.
112 */
113 ioctl_by_bdev(bdev, BLKRRPART, 0);
114 /*
115 * Since the matching blkdev_put call to the blkdev_get in
116 * this function is not called before dasd_destroy_partitions
117 * the offline open_count limit needs to be increased from
118 * 0 to 1. This is done by setting device->bdev (see
119 * dasd_generic_set_offline). As long as the partition
120 * detection is running no offline should be allowed. That
121 * is why the assignment to device->bdev is done AFTER
122 * the BLKRRPART ioctl.
123 */
124 device->bdev = bdev;
125 return 0;
126}
127
128/*
129 * Remove all inodes in the system for a device, delete the
130 * partitions and make device unusable by setting its size to zero.
131 */
132void
133dasd_destroy_partitions(struct dasd_device * device)
134{
135 /* The two structs have 168/176 byte on 31/64 bit. */
136 struct blkpg_partition bpart;
137 struct blkpg_ioctl_arg barg;
138 struct block_device *bdev;
139
140 /*
141 * Get the bdev pointer from the device structure and clear
142 * device->bdev to lower the offline open_count limit again.
143 */
144 bdev = device->bdev;
145 device->bdev = 0;
146
147 /*
148 * See fs/partition/check.c:delete_partition
149 * Can't call delete_partitions directly. Use ioctl.
150 * The ioctl also does locking and invalidation.
151 */
152 memset(&bpart, 0, sizeof(struct blkpg_partition));
153 memset(&barg, 0, sizeof(struct blkpg_ioctl_arg));
154 barg.data = &bpart;
155 barg.op = BLKPG_DEL_PARTITION;
156 for (bpart.pno = device->gdp->minors - 1; bpart.pno > 0; bpart.pno--)
157 ioctl_by_bdev(bdev, BLKPG, (unsigned long) &barg);
158
159 invalidate_partition(device->gdp, 0);
160 /* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
161 blkdev_put(bdev);
162 set_capacity(device->gdp, 0);
163}
164
165int
166dasd_gendisk_init(void)
167{
168 int rc;
169
170 /* Register to static dasd major 94 */
171 rc = register_blkdev(DASD_MAJOR, "dasd");
172 if (rc != 0) {
173 MESSAGE(KERN_WARNING,
174 "Couldn't register successfully to "
175 "major no %d", DASD_MAJOR);
176 return rc;
177 }
178 return 0;
179}
180
181void
182dasd_gendisk_exit(void)
183{
184 unregister_blkdev(DASD_MAJOR, "dasd");
185}
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