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 */ 30 int 31 dasd_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 */ 87 void 88 dasd_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 */ 99 int 100 dasd_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 */ 132 void 133 dasd_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 } 164 165 int 166 dasd_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 } 180 181 void 182 dasd_gendisk_exit(void) 183 { 184 unregister_blkdev(DASD_MAJOR, "dasd"); 185 } 186