/* * 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. * */ #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_block *block) { struct gendisk *gdp; struct dasd_device *base; int len; /* Make sure the minor for this device exists. */ base = block->base; if (base->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 = base->devindex << DASD_PARTN_BITS; gdp->fops = &dasd_device_operations; gdp->driverfs_dev = &base->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 (base->devindex > 25) { if (base->devindex > 701) { if (base->devindex > 18277) len += sprintf(gdp->disk_name + len, "%c", 'a'+(((base->devindex-18278) /17576)%26)); len += sprintf(gdp->disk_name + len, "%c", 'a'+(((base->devindex-702)/676)%26)); } len += sprintf(gdp->disk_name + len, "%c", 'a'+(((base->devindex-26)/26)%26)); } len += sprintf(gdp->disk_name + len, "%c", 'a'+(base->devindex%26)); if (block->base->features & DASD_FEATURE_READONLY) set_disk_ro(gdp, 1); gdp->private_data = block; gdp->queue = block->request_queue; block->gdp = gdp; set_capacity(block->gdp, 0); add_disk(block->gdp); return 0; } /* * Unregister and free gendisk structure for device. */ void dasd_gendisk_free(struct dasd_block *block) { if (block->gdp) { del_gendisk(block->gdp); block->gdp->queue = NULL; put_disk(block->gdp); block->gdp = NULL; } } /* * Trigger a partition detection. */ int dasd_scan_partitions(struct dasd_block *block) { struct block_device *bdev; bdev = bdget_disk(block->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. */ block->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_block *block) { /* 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 = block->bdev; block->bdev = NULL; /* * 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 = (void __force __user *) &bpart; barg.op = BLKPG_DEL_PARTITION; for (bpart.pno = block->gdp->minors - 1; bpart.pno > 0; bpart.pno--) ioctl_by_bdev(bdev, BLKPG, (unsigned long) &barg); invalidate_partition(block->gdp, 0); /* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */ blkdev_put(bdev); set_capacity(block->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"); }