[S390] dasd: add large volume support
[linux-2.6.git] / 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
9 #include <linux/buffer_head.h>
10 #include <linux/hdreg.h>
11 #include <linux/slab.h>
12 #include <asm/dasd.h>
13 #include <asm/ebcdic.h>
14 #include <asm/uaccess.h>
15 #include <asm/vtoc.h>
16
17 #include "check.h"
18 #include "ibm.h"
19
20 /*
21  * compute the block number from a
22  * cyl-cyl-head-head structure
23  */
24 static sector_t
25 cchh2blk (struct vtoc_cchh *ptr, struct hd_geometry *geo) {
26
27         sector_t cyl;
28         __u16 head;
29
30         /*decode cylinder and heads for large volumes */
31         cyl = ptr->hh & 0xFFF0;
32         cyl <<= 12;
33         cyl |= ptr->cc;
34         head = ptr->hh & 0x000F;
35         return cyl * geo->heads * geo->sectors +
36                head * geo->sectors;
37 }
38
39 /*
40  * compute the block number from a
41  * cyl-cyl-head-head-block structure
42  */
43 static sector_t
44 cchhb2blk (struct vtoc_cchhb *ptr, struct hd_geometry *geo) {
45
46         sector_t cyl;
47         __u16 head;
48
49         /*decode cylinder and heads for large volumes */
50         cyl = ptr->hh & 0xFFF0;
51         cyl <<= 12;
52         cyl |= ptr->cc;
53         head = ptr->hh & 0x000F;
54         return  cyl * geo->heads * geo->sectors +
55                 head * geo->sectors +
56                 ptr->b;
57 }
58
59 /*
60  */
61 int
62 ibm_partition(struct parsed_partitions *state, struct block_device *bdev)
63 {
64         int blocksize, res;
65         loff_t i_size, offset, size, fmt_size;
66         dasd_information2_t *info;
67         struct hd_geometry *geo;
68         char type[5] = {0,};
69         char name[7] = {0,};
70         union label_t {
71                 struct vtoc_volume_label_cdl vol;
72                 struct vtoc_volume_label_ldl lnx;
73                 struct vtoc_cms_label cms;
74         } *label;
75         unsigned char *data;
76         Sector sect;
77
78         res = 0;
79         blocksize = bdev_hardsect_size(bdev);
80         if (blocksize <= 0)
81                 goto out_exit;
82         i_size = i_size_read(bdev->bd_inode);
83         if (i_size == 0)
84                 goto out_exit;
85
86         info = kmalloc(sizeof(dasd_information2_t), GFP_KERNEL);
87         if (info == NULL)
88                 goto out_exit;
89         geo = kmalloc(sizeof(struct hd_geometry), GFP_KERNEL);
90         if (geo == NULL)
91                 goto out_nogeo;
92         label = kmalloc(sizeof(union label_t), GFP_KERNEL);
93         if (label == NULL)
94                 goto out_nolab;
95
96         if (ioctl_by_bdev(bdev, BIODASDINFO2, (unsigned long)info) != 0 ||
97             ioctl_by_bdev(bdev, HDIO_GETGEO, (unsigned long)geo) != 0)
98                 goto out_freeall;
99
100         /*
101          * Get volume label, extract name and type.
102          */
103         data = read_dev_sector(bdev, info->label_block*(blocksize/512), &sect);
104         if (data == NULL)
105                 goto out_readerr;
106
107         memcpy(label, data, sizeof(union label_t));
108         put_dev_sector(sect);
109
110         if ((!info->FBA_layout) && (!strcmp(info->type, "ECKD"))) {
111                 strncpy(type, label->vol.vollbl, 4);
112                 strncpy(name, label->vol.volid, 6);
113         } else {
114                 strncpy(type, label->lnx.vollbl, 4);
115                 strncpy(name, label->lnx.volid, 6);
116         }
117         EBCASC(type, 4);
118         EBCASC(name, 6);
119
120         res = 1;
121
122         /*
123          * Three different formats: LDL, CDL and unformated disk
124          *
125          * identified by info->format
126          *
127          * unformated disks we do not have to care about
128          */
129         if (info->format == DASD_FORMAT_LDL) {
130                 if (strncmp(type, "CMS1", 4) == 0) {
131                         /*
132                          * VM style CMS1 labeled disk
133                          */
134                         blocksize = label->cms.block_size;
135                         if (label->cms.disk_offset != 0) {
136                                 printk("CMS1/%8s(MDSK):", name);
137                                 /* disk is reserved minidisk */
138                                 offset = label->cms.disk_offset;
139                                 size = (label->cms.block_count - 1)
140                                         * (blocksize >> 9);
141                         } else {
142                                 printk("CMS1/%8s:", name);
143                                 offset = (info->label_block + 1);
144                                 size = label->cms.block_count
145                                         * (blocksize >> 9);
146                         }
147                         put_partition(state, 1, offset*(blocksize >> 9),
148                                       size-offset*(blocksize >> 9));
149                 } else {
150                         if (strncmp(type, "LNX1", 4) == 0) {
151                                 printk("LNX1/%8s:", name);
152                                 if (label->lnx.ldl_version == 0xf2) {
153                                         fmt_size = label->lnx.formatted_blocks
154                                                 * (blocksize >> 9);
155                                 } else if (!strcmp(info->type, "ECKD")) {
156                                         /* formated w/o large volume support */
157                                         fmt_size = geo->cylinders * geo->heads
158                                               * geo->sectors * (blocksize >> 9);
159                                 } else {
160                                         /* old label and no usable disk geometry
161                                          * (e.g. DIAG) */
162                                         fmt_size = i_size >> 9;
163                                 }
164                                 size = i_size >> 9;
165                                 if (fmt_size < size)
166                                         size = fmt_size;
167                                 offset = (info->label_block + 1);
168                         } else {
169                                 /* unlabeled disk */
170                                 printk("(nonl)");
171                                 size = i_size >> 9;
172                                 offset = (info->label_block + 1);
173                         }
174                         put_partition(state, 1, offset*(blocksize >> 9),
175                                       size-offset*(blocksize >> 9));
176                 }
177         } else if (info->format == DASD_FORMAT_CDL) {
178                 /*
179                  * New style CDL formatted disk
180                  */
181                 sector_t blk;
182                 int counter;
183
184                 /*
185                  * check if VOL1 label is available
186                  * if not, something is wrong, skipping partition detection
187                  */
188                 if (strncmp(type, "VOL1",  4) == 0) {
189                         printk("VOL1/%8s:", name);
190                         /*
191                          * get block number and read then go through format1
192                          * labels
193                          */
194                         blk = cchhb2blk(&label->vol.vtoc, geo) + 1;
195                         counter = 0;
196                         data = read_dev_sector(bdev, blk * (blocksize/512),
197                                                &sect);
198                         while (data != NULL) {
199                                 struct vtoc_format1_label f1;
200
201                                 memcpy(&f1, data,
202                                        sizeof(struct vtoc_format1_label));
203                                 put_dev_sector(sect);
204
205                                 /* skip FMT4 / FMT5 / FMT7 labels */
206                                 if (f1.DS1FMTID == _ascebc['4']
207                                     || f1.DS1FMTID == _ascebc['5']
208                                     || f1.DS1FMTID == _ascebc['7']
209                                     || f1.DS1FMTID == _ascebc['9']) {
210                                         blk++;
211                                         data = read_dev_sector(bdev, blk *
212                                                                (blocksize/512),
213                                                                 &sect);
214                                         continue;
215                                 }
216
217                                 /* only FMT1 and 8 labels valid at this point */
218                                 if (f1.DS1FMTID != _ascebc['1'] &&
219                                     f1.DS1FMTID != _ascebc['8'])
220                                         break;
221
222                                 /* OK, we got valid partition data */
223                                 offset = cchh2blk(&f1.DS1EXT1.llimit, geo);
224                                 size  = cchh2blk(&f1.DS1EXT1.ulimit, geo) -
225                                         offset + geo->sectors;
226                                 if (counter >= state->limit)
227                                         break;
228                                 put_partition(state, counter + 1,
229                                               offset * (blocksize >> 9),
230                                               size * (blocksize >> 9));
231                                 counter++;
232                                 blk++;
233                                 data = read_dev_sector(bdev,
234                                                        blk * (blocksize/512),
235                                                        &sect);
236                         }
237
238                         if (!data)
239                                 /* Are we not supposed to report this ? */
240                                 goto out_readerr;
241                 } else
242                         printk(KERN_WARNING "Warning, expected Label VOL1 not "
243                                "found, treating as CDL formated Disk");
244
245         }
246
247         printk("\n");
248         goto out_freeall;
249
250
251 out_readerr:
252         res = -1;
253 out_freeall:
254         kfree(label);
255 out_nolab:
256         kfree(geo);
257 out_nogeo:
258         kfree(info);
259 out_exit:
260         return res;
261 }