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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 feature_ro
= dasd_get_feature(device
->cdev
, DASD_FEATURE_READONLY
);
44 gdp
= alloc_disk(1 << DASD_PARTN_BITS
);
48 /* Initialize gendisk structure. */
49 gdp
->major
= DASD_MAJOR
;
50 gdp
->first_minor
= device
->devindex
<< DASD_PARTN_BITS
;
51 gdp
->fops
= &dasd_device_operations
;
52 gdp
->driverfs_dev
= &device
->cdev
->dev
;
56 * dasda - dasdz : 26 devices
57 * dasdaa - dasdzz : 676 devices, added up = 702
58 * dasdaaa - dasdzzz : 17576 devices, added up = 18278
59 * dasdaaaa - dasdzzzz : 456976 devices, added up = 475252
61 len
= sprintf(gdp
->disk_name
, "dasd");
62 if (device
->devindex
> 25) {
63 if (device
->devindex
> 701) {
64 if (device
->devindex
> 18277)
65 len
+= sprintf(gdp
->disk_name
+ len
, "%c",
66 'a'+(((device
->devindex
-18278)
68 len
+= sprintf(gdp
->disk_name
+ len
, "%c",
69 'a'+(((device
->devindex
-702)/676)%26));
71 len
+= sprintf(gdp
->disk_name
+ len
, "%c",
72 'a'+(((device
->devindex
-26)/26)%26));
74 len
+= sprintf(gdp
->disk_name
+ len
, "%c", 'a'+(device
->devindex
%26));
76 sprintf(gdp
->devfs_name
, "dasd/%s", device
->cdev
->dev
.bus_id
);
80 gdp
->private_data
= device
;
81 gdp
->queue
= device
->request_queue
;
83 set_capacity(device
->gdp
, 0);
84 add_disk(device
->gdp
);
89 * Unregister and free gendisk structure for device.
92 dasd_gendisk_free(struct dasd_device
*device
)
94 del_gendisk(device
->gdp
);
95 device
->gdp
->queue
= 0;
96 put_disk(device
->gdp
);
101 * Trigger a partition detection.
104 dasd_scan_partitions(struct dasd_device
* device
)
106 struct block_device
*bdev
;
108 /* Make the disk known. */
109 set_capacity(device
->gdp
, device
->blocks
<< device
->s2b_shift
);
110 bdev
= bdget_disk(device
->gdp
, 0);
111 if (!bdev
|| blkdev_get(bdev
, FMODE_READ
, 1) < 0)
114 * See fs/partition/check.c:register_disk,rescan_partitions
115 * Can't call rescan_partitions directly. Use ioctl.
117 ioctl_by_bdev(bdev
, BLKRRPART
, 0);
119 * Since the matching blkdev_put call to the blkdev_get in
120 * this function is not called before dasd_destroy_partitions
121 * the offline open_count limit needs to be increased from
122 * 0 to 1. This is done by setting device->bdev (see
123 * dasd_generic_set_offline). As long as the partition
124 * detection is running no offline should be allowed. That
125 * is why the assignment to device->bdev is done AFTER
126 * the BLKRRPART ioctl.
133 * Remove all inodes in the system for a device, delete the
134 * partitions and make device unusable by setting its size to zero.
137 dasd_destroy_partitions(struct dasd_device
* device
)
139 /* The two structs have 168/176 byte on 31/64 bit. */
140 struct blkpg_partition bpart
;
141 struct blkpg_ioctl_arg barg
;
142 struct block_device
*bdev
;
145 * Get the bdev pointer from the device structure and clear
146 * device->bdev to lower the offline open_count limit again.
152 * See fs/partition/check.c:delete_partition
153 * Can't call delete_partitions directly. Use ioctl.
154 * The ioctl also does locking and invalidation.
156 memset(&bpart
, 0, sizeof(struct blkpg_partition
));
157 memset(&barg
, 0, sizeof(struct blkpg_ioctl_arg
));
159 barg
.op
= BLKPG_DEL_PARTITION
;
160 for (bpart
.pno
= device
->gdp
->minors
- 1; bpart
.pno
> 0; bpart
.pno
--)
161 ioctl_by_bdev(bdev
, BLKPG
, (unsigned long) &barg
);
163 invalidate_partition(device
->gdp
, 0);
164 /* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
166 set_capacity(device
->gdp
, 0);
170 dasd_gendisk_init(void)
174 /* Register to static dasd major 94 */
175 rc
= register_blkdev(DASD_MAJOR
, "dasd");
177 MESSAGE(KERN_WARNING
,
178 "Couldn't register successfully to "
179 "major no %d", DASD_MAJOR
);
186 dasd_gendisk_exit(void)
188 unregister_blkdev(DASD_MAJOR
, "dasd");