/* hptraid.c Copyright (C) 2001 Red Hat, Inc. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. You should have received a copy of the GNU General Public License (for example /usr/src/linux/COPYING); if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. Authors: Arjan van de Ven Based on work Copyleft (C) 2001 by Wilfried Weissmann Copyright (C) 1994-96 Marc ZYNGIER Based on work done by Søren Schmidt for FreeBSD */ #include #include #include #include #include #include #include #include #include #include #include #include "ataraid.h" static int hptraid_open(struct inode * inode, struct file * filp); static int hptraid_release(struct inode * inode, struct file * filp); static int hptraid_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg); static int hptraid_make_request (request_queue_t *q, int rw, struct buffer_head * bh); struct hptdisk { kdev_t device; unsigned long sectors; struct block_device *bdev; }; struct hptraid { unsigned int stride; unsigned int disks; unsigned long sectors; struct geom geom; struct hptdisk disk[8]; unsigned long cutoff[8]; unsigned int cutoff_disks[8]; }; static struct raid_device_operations hptraid_ops = { open: hptraid_open, release: hptraid_release, ioctl: hptraid_ioctl, make_request: hptraid_make_request }; static struct hptraid raid[16]; static int hptraid_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { unsigned int minor; unsigned char val; unsigned long sectors; if (!inode || !inode->i_rdev) return -EINVAL; minor = MINOR(inode->i_rdev)>>SHIFT; switch (cmd) { case BLKGETSIZE: /* Return device size */ if (!arg) return -EINVAL; sectors = ataraid_gendisk.part[MINOR(inode->i_rdev)].nr_sects; if (MINOR(inode->i_rdev)&15) return put_user(sectors, (unsigned long *) arg); return put_user(raid[minor].sectors , (unsigned long *) arg); break; case HDIO_GETGEO: { struct hd_geometry *loc = (struct hd_geometry *) arg; unsigned short bios_cyl; if (!loc) return -EINVAL; val = 255; if (put_user(val, (byte *) &loc->heads)) return -EFAULT; val=63; if (put_user(val, (byte *) &loc->sectors)) return -EFAULT; bios_cyl = raid[minor].sectors/63/255; if (put_user(bios_cyl, (unsigned short *) &loc->cylinders)) return -EFAULT; if (put_user((unsigned)ataraid_gendisk.part[MINOR(inode->i_rdev)].start_sect, (unsigned long *) &loc->start)) return -EFAULT; return 0; } case HDIO_GETGEO_BIG: { struct hd_big_geometry *loc = (struct hd_big_geometry *) arg; unsigned int bios_cyl; if (!loc) return -EINVAL; val = 255; if (put_user(val, (byte *) &loc->heads)) return -EFAULT; val = 63; if (put_user(val, (byte *) &loc->sectors)) return -EFAULT; bios_cyl = raid[minor].sectors/63/255; if (put_user(bios_cyl, (unsigned int *) &loc->cylinders)) return -EFAULT; if (put_user((unsigned)ataraid_gendisk.part[MINOR(inode->i_rdev)].start_sect, (unsigned long *) &loc->start)) return -EFAULT; return 0; } case BLKROSET: case BLKROGET: case BLKSSZGET: return blk_ioctl(inode->i_rdev, cmd, arg); default: return -EINVAL; }; return 0; } static int hptraid_make_request (request_queue_t *q, int rw, struct buffer_head * bh) { unsigned long rsect; unsigned long rsect_left,rsect_accum = 0; unsigned long block; unsigned int disk=0,real_disk=0; int i; int device; struct hptraid *thisraid; rsect = bh->b_rsector; /* Ok. We need to modify this sector number to a new disk + new sector number. * If there are disks of different sizes, this gets tricky. * Example with 3 disks (1Gb, 4Gb and 5 GB): * The first 3 Gb of the "RAID" are evenly spread over the 3 disks. * Then things get interesting. The next 2Gb (RAID view) are spread across disk 2 and 3 * and the last 1Gb is disk 3 only. * * the way this is solved is like this: We have a list of "cutoff" points where everytime * a disk falls out of the "higher" count, we mark the max sector. So once we pass a cutoff * point, we have to divide by one less. */ device = (bh->b_rdev >> SHIFT)&MAJOR_MASK; thisraid = &raid[device]; if (thisraid->stride==0) thisraid->stride=1; /* Partitions need adding of the start sector of the partition to the requested sector */ rsect += ataraid_gendisk.part[MINOR(bh->b_rdev)].start_sect; /* Woops we need to split the request to avoid crossing a stride barrier */ if ((rsect/thisraid->stride) != ((rsect+(bh->b_size/512)-1)/thisraid->stride)) { return -1; } rsect_left = rsect; for (i=0;i<8;i++) { if (thisraid->cutoff_disks[i]==0) break; if (rsect > thisraid->cutoff[i]) { /* we're in the wrong area so far */ rsect_left -= thisraid->cutoff[i]; rsect_accum += thisraid->cutoff[i]/thisraid->cutoff_disks[i]; } else { block = rsect_left / thisraid->stride; disk = block % thisraid->cutoff_disks[i]; block = (block / thisraid->cutoff_disks[i]) * thisraid->stride; rsect = rsect_accum + (rsect_left % thisraid->stride) + block; break; } } for (i=0;i<8;i++) { if ((disk==0) && (thisraid->disk[i].sectors > rsect_accum)) { real_disk = i; break; } if ((disk>0) && (thisraid->disk[i].sectors >= rsect_accum)) { disk--; } } disk = real_disk; /* All but the first disk have a 10 sector offset */ if (i>0) rsect+=10; /* * The new BH_Lock semantics in ll_rw_blk.c guarantee that this * is the only IO operation happening on this bh. */ bh->b_rdev = thisraid->disk[disk].device; bh->b_rsector = rsect; /* * Let the main block layer submit the IO and resolve recursion: */ return 1; } #include "hptraid.h" static int read_disk_sb (int major, int minor, unsigned char *buffer,int bufsize) { int ret = -EINVAL; struct buffer_head *bh = NULL; kdev_t dev = MKDEV(major,minor); if (blksize_size[major]==NULL) /* device doesn't exist */ return -EINVAL; /* Superblock is at 4096+412 bytes */ set_blocksize (dev, 4096); bh = bread (dev, 1, 4096); if (bh) { memcpy (buffer, bh->b_data, bufsize); } else { printk(KERN_ERR "hptraid: Error reading superblock.\n"); goto abort; } ret = 0; abort: if (bh) brelse (bh); return ret; } static unsigned long maxsectors (int major,int minor) { unsigned long lba = 0; kdev_t dev; ide_drive_t *ideinfo; dev = MKDEV(major,minor); ideinfo = get_info_ptr (dev); if (ideinfo==NULL) return 0; /* first sector of the last cluster */ if (ideinfo->head==0) return 0; if (ideinfo->sect==0) return 0; lba = (ideinfo->capacity); return lba; } static void __init probedisk(int major, int minor,int device) { int i; struct highpoint_raid_conf *prom; static unsigned char block[4096]; struct block_device *bdev; if (maxsectors(major,minor)==0) return; if (read_disk_sb(major,minor,(unsigned char*)&block,sizeof(block))) return; prom = (struct highpoint_raid_conf*)&block[512]; if (prom->magic!= 0x5a7816f0) return; if (prom->type) { printk(KERN_INFO "hptraid: only RAID0 is supported currently\n"); return; } i = prom->disk_number; if (i<0) return; if (i>8) return; bdev = bdget(MKDEV(major,minor)); if (bdev && blkdev_get(bdev,FMODE_READ|FMODE_WRITE,0,BDEV_RAW) == 0) { int j=0; struct gendisk *gd; raid[device].disk[i].bdev = bdev; /* This is supposed to prevent others from stealing our underlying disks */ /* now blank the /proc/partitions table for the wrong partition table, so that scripts don't accidentally mount it and crash the kernel */ /* XXX: the 0 is an utter hack --hch */ gd=get_gendisk(MKDEV(major, 0)); if (gd!=NULL) { for (j=1+(minor<minor_shift);j<((minor+1)<minor_shift);j++) gd->part[j].nr_sects=0; } } raid[device].disk[i].device = MKDEV(major,minor); raid[device].disk[i].sectors = maxsectors(major,minor); raid[device].stride = (1<raid0_shift); raid[device].disks = prom->raid_disks; raid[device].sectors = prom->total_secs; } static void __init fill_cutoff(int device) { int i,j; unsigned long smallest; unsigned long bar; int count; bar = 0; for (i=0;i<8;i++) { smallest = ~0; for (j=0;j<8;j++) if ((raid[device].disk[j].sectors < smallest) && (raid[device].disk[j].sectors>bar)) smallest = raid[device].disk[j].sectors; count = 0; for (j=0;j<8;j++) if (raid[device].disk[j].sectors >= smallest) count++; smallest = smallest * count; bar = smallest; raid[device].cutoff[i] = smallest; raid[device].cutoff_disks[i] = count; } } static __init int hptraid_init_one(int device) { int i,count; probedisk(IDE0_MAJOR, 0, device); probedisk(IDE0_MAJOR, 64, device); probedisk(IDE1_MAJOR, 0, device); probedisk(IDE1_MAJOR, 64, device); probedisk(IDE2_MAJOR, 0, device); probedisk(IDE2_MAJOR, 64, device); probedisk(IDE3_MAJOR, 0, device); probedisk(IDE3_MAJOR, 64, device); fill_cutoff(device); /* Initialize the gendisk structure */ ataraid_register_disk(device,raid[device].sectors); count=0; printk(KERN_INFO "Highpoint HPT370 Softwareraid driver for linux version 0.01\n"); for (i=0;i<8;i++) { if (raid[device].disk[i].device!=0) { printk(KERN_INFO "Drive %i is %li Mb \n", i,raid[device].disk[i].sectors/2048); count++; } } if (count) { printk(KERN_INFO "Raid array consists of %i drives. \n",count); return 0; } else { printk(KERN_INFO "No raid array found\n"); return -ENODEV; } } static __init int hptraid_init(void) { int retval,device; device=ataraid_get_device(&hptraid_ops); if (device<0) return -ENODEV; retval = hptraid_init_one(device); if (retval) ataraid_release_device(device); return retval; } static void __exit hptraid_exit (void) { int i,device; for (device = 0; device<16; device++) { for (i=0;i<8;i++) { struct block_device *bdev = raid[device].disk[i].bdev; raid[device].disk[i].bdev = NULL; if (bdev) blkdev_put(bdev, BDEV_RAW); } if (raid[device].sectors) ataraid_release_device(device); } } static int hptraid_open(struct inode * inode, struct file * filp) { MOD_INC_USE_COUNT; return 0; } static int hptraid_release(struct inode * inode, struct file * filp) { MOD_DEC_USE_COUNT; return 0; } module_init(hptraid_init); module_exit(hptraid_exit); MODULE_LICENSE("GPL");