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git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - drivers/s390/block/dasd_genhd.c
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
10 * gendisk related functions for the dasd driver.
15 #include <linux/config.h>
16 #include <linux/interrupt.h>
18 #include <linux/blkpg.h>
20 #include <asm/uaccess.h>
23 #define PRINTK_HEADER "dasd_gendisk:"
28 * Allocate and register gendisk structure for device.
31 dasd_gendisk_alloc(struct dasd_device
*device
)
36 /* Make sure the minor for this device exists. */
37 if (device
->devindex
>= DASD_PER_MAJOR
)
40 gdp
= alloc_disk(1 << DASD_PARTN_BITS
);
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
;
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
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)
64 len
+= sprintf(gdp
->disk_name
+ len
, "%c",
65 'a'+(((device
->devindex
-702)/676)%26));
67 len
+= sprintf(gdp
->disk_name
+ len
, "%c",
68 'a'+(((device
->devindex
-26)/26)%26));
70 len
+= sprintf(gdp
->disk_name
+ len
, "%c", 'a'+(device
->devindex
%26));
72 sprintf(gdp
->devfs_name
, "dasd/%s", device
->cdev
->dev
.bus_id
);
74 if (test_bit(DASD_FLAG_RO
, &device
->flags
))
76 gdp
->private_data
= device
;
77 gdp
->queue
= device
->request_queue
;
79 set_capacity(device
->gdp
, 0);
80 add_disk(device
->gdp
);
85 * Unregister and free gendisk structure for device.
88 dasd_gendisk_free(struct dasd_device
*device
)
90 del_gendisk(device
->gdp
);
91 device
->gdp
->queue
= 0;
92 put_disk(device
->gdp
);
97 * Trigger a partition detection.
100 dasd_scan_partitions(struct dasd_device
* device
)
102 struct block_device
*bdev
;
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)
110 * See fs/partition/check.c:register_disk,rescan_partitions
111 * Can't call rescan_partitions directly. Use ioctl.
113 ioctl_by_bdev(bdev
, BLKRRPART
, 0);
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.
129 * Remove all inodes in the system for a device, delete the
130 * partitions and make device unusable by setting its size to zero.
133 dasd_destroy_partitions(struct dasd_device
* device
)
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
;
141 * Get the bdev pointer from the device structure and clear
142 * device->bdev to lower the offline open_count limit again.
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.
152 memset(&bpart
, 0, sizeof(struct blkpg_partition
));
153 memset(&barg
, 0, sizeof(struct blkpg_ioctl_arg
));
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
);
159 invalidate_partition(device
->gdp
, 0);
160 /* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
162 set_capacity(device
->gdp
, 0);
166 dasd_gendisk_init(void)
170 /* Register to static dasd major 94 */
171 rc
= register_blkdev(DASD_MAJOR
, "dasd");
173 MESSAGE(KERN_WARNING
,
174 "Couldn't register successfully to "
175 "major no %d", DASD_MAJOR
);
182 dasd_gendisk_exit(void)
184 unregister_blkdev(DASD_MAJOR
, "dasd");