fs/partitions/ibm.c

   1 /*
   2  * File...........: linux/fs/partitions/ibm.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  *                  Volker Sameske <sameske@de.ibm.com>
   5  * Bugreports.to..: <Linux390@de.ibm.com>
   6  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
   7
   8  * History of changes (starts July 2000)
   9  * 07/10/00 Fixed detection of CMS formatted disks
  10  * 02/13/00 VTOC partition support added
  11  * 12/27/01 fixed PL030593 (CMS reserved minidisk not detected on 64 bit)
  12  * 07/24/03 no longer using contents of freed page for CMS label recognition (BZ3611)
  13  */
  14
  15 #include <linux/config.h>
  16 #include <linux/buffer_head.h>
  17 #include <linux/hdreg.h>
  18 #include <linux/slab.h>
  19 #include <asm/dasd.h>
  20 #include <asm/ebcdic.h>
  21 #include <asm/uaccess.h>
  22 #include <asm/vtoc.h>
  23
  24 #include "check.h"
  25 #include "ibm.h"
  26
  27 /*
  28  * compute the block number from a
  29  * cyl-cyl-head-head structure
  30  */
  31 static inline int
  32 cchh2blk (struct vtoc_cchh *ptr, struct hd_geometry *geo) {
  33         return ptr->cc * geo->heads * geo->sectors +
  34                ptr->hh * geo->sectors;
  35 }
  36
  37
  38 /*
  39  * compute the block number from a
  40  * cyl-cyl-head-head-block structure
  41  */
  42 static inline int
  43 cchhb2blk (struct vtoc_cchhb *ptr, struct hd_geometry *geo) {
  44         return ptr->cc * geo->heads * geo->sectors +
  45                 ptr->hh * geo->sectors +
  46                 ptr->b;
  47 }
  48
  49 /*
  50  */
  51 int
  52 ibm_partition(struct parsed_partitions *state, struct block_device *bdev)
  53 {
  54         int blocksize, offset, size;
  55         loff_t i_size;
  56         dasd_information_t *info;
  57         struct hd_geometry *geo;
  58         char type[5] = {0,};
  59         char name[7] = {0,};
  60         union label_t {
  61                 struct vtoc_volume_label vol;
  62                 struct vtoc_cms_label cms;
  63         } *label;
  64         unsigned char *data;
  65         Sector sect;
  66
  67         blocksize = bdev_hardsect_size(bdev);
  68         if (blocksize <= 0)
  69                 return 0;
  70         i_size = i_size_read(bdev->bd_inode);
  71         if (i_size == 0)
  72                 return 0;
  73
  74         if ((info = kmalloc(sizeof(dasd_information_t), GFP_KERNEL)) == NULL)
  75                 goto out_noinfo;
  76         if ((geo = kmalloc(sizeof(struct hd_geometry), GFP_KERNEL)) == NULL)
  77                 goto out_nogeo;
  78         if ((label = kmalloc(sizeof(union label_t), GFP_KERNEL)) == NULL)
  79                 goto out_nolab;
  80
  81         if (ioctl_by_bdev(bdev, BIODASDINFO, (unsigned long)info) != 0 ||
  82             ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)geo) != 0)
  83                 goto out_noioctl;
  84
  85         /*
  86          * Get volume label, extract name and type.
  87          */
  88         data = read_dev_sector(bdev, info->label_block*(blocksize/512), &sect);
  89         if (data == NULL)
  90                 goto out_readerr;
  91
  92         strncpy (type, data, 4);
  93         if ((!info->FBA_layout) && (!strcmp(info->type, "ECKD")))
  94                 strncpy(name, data + 8, 6);
  95         else
  96                 strncpy(name, data + 4, 6);
  97         memcpy(label, data, sizeof(union label_t));
  98         put_dev_sector(sect);
  99
 100         EBCASC(type, 4);
 101         EBCASC(name, 6);
 102
 103         /*
 104          * Three different types: CMS1, VOL1 and LNX1/unlabeled
 105          */
 106         if (strncmp(type, "CMS1", 4) == 0) {
 107                 /*
 108                  * VM style CMS1 labeled disk
 109                  */
 110                 if (label->cms.disk_offset != 0) {
 111                         printk("CMS1/%8s(MDSK):", name);
 112                         /* disk is reserved minidisk */
 113                         blocksize = label->cms.block_size;
 114                         offset = label->cms.disk_offset;
 115                         size = (label->cms.block_count - 1) * (blocksize >> 9);
 116                 } else {
 117                         printk("CMS1/%8s:", name);
 118                         offset = (info->label_block + 1);
 119                         size = i_size >> 9;
 120                 }
 121                 put_partition(state, 1, offset*(blocksize >> 9),
 122                                  size-offset*(blocksize >> 9));
 123         } else if ((strncmp(type, "VOL1", 4) == 0) &&
 124                 (!info->FBA_layout) && (!strcmp(info->type, "ECKD"))) {
 125                 /*
 126                  * New style VOL1 labeled disk
 127                  */
 128                 unsigned int blk;
 129                 int counter;
 130
 131                 printk("VOL1/%8s:", name);
 132
 133                 /* get block number and read then go through format1 labels */
 134                 blk = cchhb2blk(&label->vol.vtoc, geo) + 1;
 135                 counter = 0;
 136                 while ((data = read_dev_sector(bdev, blk*(blocksize/512),
 137                                                &sect)) != NULL) {
 138                         struct vtoc_format1_label f1;
 139
 140                         memcpy(&f1, data, sizeof(struct vtoc_format1_label));
 141                         put_dev_sector(sect);
 142
 143                         /* skip FMT4 / FMT5 / FMT7 labels */
 144                         if (f1.DS1FMTID == _ascebc['4']
 145                             || f1.DS1FMTID == _ascebc['5']
 146                             || f1.DS1FMTID == _ascebc['7']) {
 147                                 blk++;
 148                                 continue;
 149                         }
 150
 151                         /* only FMT1 valid at this point */
 152                         if (f1.DS1FMTID != _ascebc['1'])
 153                                 break;
 154
 155                         /* OK, we got valid partition data */
 156                         offset = cchh2blk(&f1.DS1EXT1.llimit, geo);
 157                         size  = cchh2blk(&f1.DS1EXT1.ulimit, geo) -
 158                                 offset + geo->sectors;
 159                         if (counter >= state->limit)
 160                                 break;
 161                         put_partition(state, counter + 1,
 162                                          offset * (blocksize >> 9),
 163                                          size * (blocksize >> 9));
 164                         counter++;
 165                         blk++;
 166                 }
 167         } else {
 168                 /*
 169                  * Old style LNX1 or unlabeled disk
 170                  */
 171                 if (strncmp(type, "LNX1", 4) == 0)
 172                         printk ("LNX1/%8s:", name);
 173                 else
 174                         printk("(nonl)/%8s:", name);
 175                 offset = (info->label_block + 1);
 176                 size = i_size >> 9;
 177                 put_partition(state, 1, offset*(blocksize >> 9),
 178                                  size-offset*(blocksize >> 9));
 179         }
 180
 181         printk("\n");
 182         kfree(label);
 183         kfree(geo);
 184         kfree(info);
 185         return 1;
 186
 187 out_readerr:
 188 out_noioctl:
 189         kfree(label);
 190 out_nolab:
 191         kfree(geo);
 192 out_nogeo:
 193         kfree(info);
 194 out_noinfo:
 195         return 0;
 196 }