File: /usr/src/linux/fs/udf/partition.c
1 /*
2 * partition.c
3 *
4 * PURPOSE
5 * Partition handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * CONTACTS
8 * E-mail regarding any portion of the Linux UDF file system should be
9 * directed to the development team mailing list (run by majordomo):
10 * linux_udf@hpesjro.fc.hp.com
11 *
12 * COPYRIGHT
13 * This file is distributed under the terms of the GNU General Public
14 * License (GPL). Copies of the GPL can be obtained from:
15 * ftp://prep.ai.mit.edu/pub/gnu/GPL
16 * Each contributing author retains all rights to their own work.
17 *
18 * (C) 1998-2000 Ben Fennema
19 *
20 * HISTORY
21 *
22 * 12/06/98 blf Created file.
23 *
24 */
25
26 #include "udfdecl.h"
27 #include "udf_sb.h"
28 #include "udf_i.h"
29
30 #include <linux/fs.h>
31 #include <linux/string.h>
32 #include <linux/udf_fs.h>
33 #include <linux/slab.h>
34
35 inline Uint32 udf_get_pblock(struct super_block *sb, Uint32 block, Uint16 partition, Uint32 offset)
36 {
37 if (partition >= UDF_SB_NUMPARTS(sb))
38 {
39 udf_debug("block=%d, partition=%d, offset=%d: invalid partition\n",
40 block, partition, offset);
41 return 0xFFFFFFFF;
42 }
43 if (UDF_SB_PARTFUNC(sb, partition))
44 return UDF_SB_PARTFUNC(sb, partition)(sb, block, partition, offset);
45 else
46 return UDF_SB_PARTROOT(sb, partition) + block + offset;
47 }
48
49 Uint32 udf_get_pblock_virt15(struct super_block *sb, Uint32 block, Uint16 partition, Uint32 offset)
50 {
51 struct buffer_head *bh = NULL;
52 Uint32 newblock;
53 Uint32 index;
54 Uint32 loc;
55
56 index = (sb->s_blocksize - UDF_SB_TYPEVIRT(sb,partition).s_start_offset) / sizeof(Uint32);
57
58 if (block > UDF_SB_TYPEVIRT(sb,partition).s_num_entries)
59 {
60 udf_debug("Trying to access block beyond end of VAT (%d max %d)\n",
61 block, UDF_SB_TYPEVIRT(sb,partition).s_num_entries);
62 return 0xFFFFFFFF;
63 }
64
65 if (block >= index)
66 {
67 block -= index;
68 newblock = 1 + (block / (sb->s_blocksize / sizeof(Uint32)));
69 index = block % (sb->s_blocksize / sizeof(Uint32));
70 }
71 else
72 {
73 newblock = 0;
74 index = UDF_SB_TYPEVIRT(sb,partition).s_start_offset / sizeof(Uint32) + block;
75 }
76
77 loc = udf_block_map(UDF_SB_VAT(sb), newblock);
78
79 if (!(bh = bread(sb->s_dev, loc, sb->s_blocksize)))
80 {
81 udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%d,%d) VAT: %d[%d]\n",
82 sb, block, partition, loc, index);
83 return 0xFFFFFFFF;
84 }
85
86 loc = le32_to_cpu(((Uint32 *)bh->b_data)[index]);
87
88 udf_release_data(bh);
89
90 if (UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum == partition)
91 {
92 udf_debug("recursive call to udf_get_pblock!\n");
93 return 0xFFFFFFFF;
94 }
95
96 return udf_get_pblock(sb, loc, UDF_I_LOCATION(UDF_SB_VAT(sb)).partitionReferenceNum, offset);
97 }
98
99 inline Uint32 udf_get_pblock_virt20(struct super_block *sb, Uint32 block, Uint16 partition, Uint32 offset)
100 {
101 return udf_get_pblock_virt15(sb, block, partition, offset);
102 }
103
104 Uint32 udf_get_pblock_spar15(struct super_block *sb, Uint32 block, Uint16 partition, Uint32 offset)
105 {
106 int i;
107 struct SparingTable *st = NULL;
108 Uint32 packet = (block + offset) & ~(UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1);
109
110 for (i=0; i<4; i++)
111 {
112 if (UDF_SB_TYPESPAR(sb,partition).s_spar_map[i] != NULL)
113 {
114 st = (struct SparingTable *)UDF_SB_TYPESPAR(sb,partition).s_spar_map[i]->b_data;
115 break;
116 }
117 }
118
119 if (st)
120 {
121 for (i=0; i<st->reallocationTableLen; i++)
122 {
123 if (le32_to_cpu(st->mapEntry[i].origLocation) >= 0xFFFFFFF0)
124 break;
125 else if (le32_to_cpu(st->mapEntry[i].origLocation) == packet)
126 {
127 return le32_to_cpu(st->mapEntry[i].mappedLocation) +
128 ((block + offset) & (UDF_SB_TYPESPAR(sb,partition).s_packet_len - 1));
129 }
130 else if (le32_to_cpu(st->mapEntry[i].origLocation) > packet)
131 break;
132 }
133 }
134 return UDF_SB_PARTROOT(sb,partition) + block + offset;
135 }
136
137 int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
138 {
139 struct udf_sparing_data *sdata;
140 struct SparingTable *st = NULL;
141 SparingEntry mapEntry;
142 Uint32 packet;
143 int i, j, k, l;
144
145 for (i=0; i<UDF_SB_NUMPARTS(sb); i++)
146 {
147 if (old_block > UDF_SB_PARTROOT(sb,i) &&
148 old_block < UDF_SB_PARTROOT(sb,i) + UDF_SB_PARTLEN(sb,i))
149 {
150 sdata = &UDF_SB_TYPESPAR(sb,i);
151 packet = (old_block - UDF_SB_PARTROOT(sb,i)) & ~(sdata->s_packet_len - 1);
152
153 for (j=0; j<4; j++)
154 {
155 if (UDF_SB_TYPESPAR(sb,i).s_spar_map[j] != NULL)
156 {
157 st = (struct SparingTable *)sdata->s_spar_map[j]->b_data;
158 break;
159 }
160 }
161
162 if (!st)
163 return 1;
164
165 for (k=0; k<st->reallocationTableLen; k++)
166 {
167 if (le32_to_cpu(st->mapEntry[k].origLocation) == 0xFFFFFFFF)
168 {
169 for (; j<4; j++)
170 {
171 if (sdata->s_spar_map[j])
172 {
173 st = (struct SparingTable *)sdata->s_spar_map[j]->b_data;
174 st->mapEntry[k].origLocation = cpu_to_le32(packet);
175 udf_update_tag((char *)st, sizeof(struct SparingTable) + st->reallocationTableLen * sizeof(SparingEntry));
176 mark_buffer_dirty(sdata->s_spar_map[j]);
177 }
178 }
179 *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
180 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
181 return 0;
182 }
183 else if (le32_to_cpu(st->mapEntry[k].origLocation) == packet)
184 {
185 *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
186 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
187 return 0;
188 }
189 else if (le32_to_cpu(st->mapEntry[k].origLocation) > packet)
190 break;
191 }
192 for (l=k; l<st->reallocationTableLen; l++)
193 {
194 if (le32_to_cpu(st->mapEntry[l].origLocation) == 0xFFFFFFFF)
195 {
196 for (; j<4; j++)
197 {
198 if (sdata->s_spar_map[j])
199 {
200 st = (struct SparingTable *)sdata->s_spar_map[j]->b_data;
201 mapEntry = st->mapEntry[l];
202 mapEntry.origLocation = cpu_to_le32(packet);
203 memmove(&st->mapEntry[k+1], &st->mapEntry[k], (l-k)*sizeof(SparingEntry));
204 st->mapEntry[k] = mapEntry;
205 udf_update_tag((char *)st, sizeof(struct SparingTable) + st->reallocationTableLen * sizeof(SparingEntry));
206 mark_buffer_dirty(sdata->s_spar_map[j]);
207 }
208 }
209 *new_block = le32_to_cpu(st->mapEntry[k].mappedLocation) +
210 ((old_block - UDF_SB_PARTROOT(sb,i)) & (sdata->s_packet_len - 1));
211 return 0;
212 }
213 }
214 return 1;
215 }
216 }
217 if (i == UDF_SB_NUMPARTS(sb))
218 {
219 /* outside of partitions */
220 /* for now, fail =) */
221 return 1;
222 }
223
224 return 0;
225 }
226