1/*
2 * partition.c
3 *
4 * PURPOSE
5 *      Partition handling routines for the OSTA-UDF(tm) filesystem.
6 *
7 * COPYRIGHT
8 *      This file is distributed under the terms of the GNU General Public
9 *      License (GPL). Copies of the GPL can be obtained from:
10 *              ftp://prep.ai.mit.edu/pub/gnu/GPL
11 *      Each contributing author retains all rights to their own work.
12 *
13 *  (C) 1998-2001 Ben Fennema
14 *
15 * HISTORY
16 *
17 * 12/06/98 blf  Created file.
18 *
19 */
20
21#include "udfdecl.h"
22#include "udf_sb.h"
23#include "udf_i.h"
24
25#include <linux/fs.h>
26#include <linux/string.h>
27#include <linux/mutex.h>
28
29uint32_t udf_get_pblock(struct super_block *sb, uint32_t block,
30			uint16_t partition, uint32_t offset)
31{
32	struct udf_sb_info *sbi = UDF_SB(sb);
33	struct udf_part_map *map;
34	if (partition >= sbi->s_partitions) {
35		udf_debug("block=%d, partition=%d, offset=%d: invalid partition\n",
36			  block, partition, offset);
37		return 0xFFFFFFFF;
38	}
39	map = &sbi->s_partmaps[partition];
40	if (map->s_partition_func)
41		return map->s_partition_func(sb, block, partition, offset);
42	else
43		return map->s_partition_root + block + offset;
44}
45
46uint32_t udf_get_pblock_virt15(struct super_block *sb, uint32_t block,
47			       uint16_t partition, uint32_t offset)
48{
49	struct buffer_head *bh = NULL;
50	uint32_t newblock;
51	uint32_t index;
52	uint32_t loc;
53	struct udf_sb_info *sbi = UDF_SB(sb);
54	struct udf_part_map *map;
55	struct udf_virtual_data *vdata;
56	struct udf_inode_info *iinfo = UDF_I(sbi->s_vat_inode);
57
58	map = &sbi->s_partmaps[partition];
59	vdata = &map->s_type_specific.s_virtual;
60
61	if (block > vdata->s_num_entries) {
62		udf_debug("Trying to access block beyond end of VAT (%d max %d)\n",
63			  block, vdata->s_num_entries);
64		return 0xFFFFFFFF;
65	}
66
67	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
68		loc = le32_to_cpu(((__le32 *)(iinfo->i_ext.i_data +
69			vdata->s_start_offset))[block]);
70		goto translate;
71	}
72	index = (sb->s_blocksize - vdata->s_start_offset) / sizeof(uint32_t);
73	if (block >= index) {
74		block -= index;
75		newblock = 1 + (block / (sb->s_blocksize / sizeof(uint32_t)));
76		index = block % (sb->s_blocksize / sizeof(uint32_t));
77	} else {
78		newblock = 0;
79		index = vdata->s_start_offset / sizeof(uint32_t) + block;
80	}
81
82	loc = udf_block_map(sbi->s_vat_inode, newblock);
83
84	bh = sb_bread(sb, loc);
85	if (!bh) {
86		udf_debug("get_pblock(UDF_VIRTUAL_MAP:%p,%d,%d) VAT: %d[%d]\n",
87			  sb, block, partition, loc, index);
88		return 0xFFFFFFFF;
89	}
90
91	loc = le32_to_cpu(((__le32 *)bh->b_data)[index]);
92
93	brelse(bh);
94
95translate:
96	if (iinfo->i_location.partitionReferenceNum == partition) {
97		udf_debug("recursive call to udf_get_pblock!\n");
98		return 0xFFFFFFFF;
99	}
100
101	return udf_get_pblock(sb, loc,
102			      iinfo->i_location.partitionReferenceNum,
103			      offset);
104}
105
106inline uint32_t udf_get_pblock_virt20(struct super_block *sb, uint32_t block,
107				      uint16_t partition, uint32_t offset)
108{
109	return udf_get_pblock_virt15(sb, block, partition, offset);
110}
111
112uint32_t udf_get_pblock_spar15(struct super_block *sb, uint32_t block,
113			       uint16_t partition, uint32_t offset)
114{
115	int i;
116	struct sparingTable *st = NULL;
117	struct udf_sb_info *sbi = UDF_SB(sb);
118	struct udf_part_map *map;
119	uint32_t packet;
120	struct udf_sparing_data *sdata;
121
122	map = &sbi->s_partmaps[partition];
123	sdata = &map->s_type_specific.s_sparing;
124	packet = (block + offset) & ~(sdata->s_packet_len - 1);
125
126	for (i = 0; i < 4; i++) {
127		if (sdata->s_spar_map[i] != NULL) {
128			st = (struct sparingTable *)
129					sdata->s_spar_map[i]->b_data;
130			break;
131		}
132	}
133
134	if (st) {
135		for (i = 0; i < le16_to_cpu(st->reallocationTableLen); i++) {
136			struct sparingEntry *entry = &st->mapEntry[i];
137			u32 origLoc = le32_to_cpu(entry->origLocation);
138			if (origLoc >= 0xFFFFFFF0)
139				break;
140			else if (origLoc == packet)
141				return le32_to_cpu(entry->mappedLocation) +
142					((block + offset) &
143						(sdata->s_packet_len - 1));
144			else if (origLoc > packet)
145				break;
146		}
147	}
148
149	return map->s_partition_root + block + offset;
150}
151
152int udf_relocate_blocks(struct super_block *sb, long old_block, long *new_block)
153{
154	struct udf_sparing_data *sdata;
155	struct sparingTable *st = NULL;
156	struct sparingEntry mapEntry;
157	uint32_t packet;
158	int i, j, k, l;
159	struct udf_sb_info *sbi = UDF_SB(sb);
160	u16 reallocationTableLen;
161	struct buffer_head *bh;
162	int ret = 0;
163
164	mutex_lock(&sbi->s_alloc_mutex);
165	for (i = 0; i < sbi->s_partitions; i++) {
166		struct udf_part_map *map = &sbi->s_partmaps[i];
167		if (old_block > map->s_partition_root &&
168		    old_block < map->s_partition_root + map->s_partition_len) {
169			sdata = &map->s_type_specific.s_sparing;
170			packet = (old_block - map->s_partition_root) &
171						~(sdata->s_packet_len - 1);
172
173			for (j = 0; j < 4; j++)
174				if (sdata->s_spar_map[j] != NULL) {
175					st = (struct sparingTable *)
176						sdata->s_spar_map[j]->b_data;
177					break;
178				}
179
180			if (!st) {
181				ret = 1;
182				goto out;
183			}
184
185			reallocationTableLen =
186					le16_to_cpu(st->reallocationTableLen);
187			for (k = 0; k < reallocationTableLen; k++) {
188				struct sparingEntry *entry = &st->mapEntry[k];
189				u32 origLoc = le32_to_cpu(entry->origLocation);
190
191				if (origLoc == 0xFFFFFFFF) {
192					for (; j < 4; j++) {
193						int len;
194						bh = sdata->s_spar_map[j];
195						if (!bh)
196							continue;
197
198						st = (struct sparingTable *)
199								bh->b_data;
200						entry->origLocation =
201							cpu_to_le32(packet);
202						len =
203						  sizeof(struct sparingTable) +
204						  reallocationTableLen *
205						  sizeof(struct sparingEntry);
206						udf_update_tag((char *)st, len);
207						mark_buffer_dirty(bh);
208					}
209					*new_block = le32_to_cpu(
210							entry->mappedLocation) +
211						     ((old_block -
212							map->s_partition_root) &
213						     (sdata->s_packet_len - 1));
214					ret = 0;
215					goto out;
216				} else if (origLoc == packet) {
217					*new_block = le32_to_cpu(
218							entry->mappedLocation) +
219						     ((old_block -
220							map->s_partition_root) &
221						     (sdata->s_packet_len - 1));
222					ret = 0;
223					goto out;
224				} else if (origLoc > packet)
225					break;
226			}
227
228			for (l = k; l < reallocationTableLen; l++) {
229				struct sparingEntry *entry = &st->mapEntry[l];
230				u32 origLoc = le32_to_cpu(entry->origLocation);
231
232				if (origLoc != 0xFFFFFFFF)
233					continue;
234
235				for (; j < 4; j++) {
236					bh = sdata->s_spar_map[j];
237					if (!bh)
238						continue;
239
240					st = (struct sparingTable *)bh->b_data;
241					mapEntry = st->mapEntry[l];
242					mapEntry.origLocation =
243							cpu_to_le32(packet);
244					memmove(&st->mapEntry[k + 1],
245						&st->mapEntry[k],
246						(l - k) *
247						sizeof(struct sparingEntry));
248					st->mapEntry[k] = mapEntry;
249					udf_update_tag((char *)st,
250						sizeof(struct sparingTable) +
251						reallocationTableLen *
252						sizeof(struct sparingEntry));
253					mark_buffer_dirty(bh);
254				}
255				*new_block =
256					le32_to_cpu(
257					      st->mapEntry[k].mappedLocation) +
258					((old_block - map->s_partition_root) &
259					 (sdata->s_packet_len - 1));
260				ret = 0;
261				goto out;
262			}
263
264			ret = 1;
265			goto out;
266		} /* if old_block */
267	}
268
269	if (i == sbi->s_partitions) {
270		/* outside of partitions */
271		/* for now, fail =) */
272		ret = 1;
273	}
274
275out:
276	mutex_unlock(&sbi->s_alloc_mutex);
277	return ret;
278}
279
280static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
281					uint16_t partition, uint32_t offset)
282{
283	struct super_block *sb = inode->i_sb;
284	struct udf_part_map *map;
285	struct kernel_lb_addr eloc;
286	uint32_t elen;
287	sector_t ext_offset;
288	struct extent_position epos = {};
289	uint32_t phyblock;
290
291	if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
292						(EXT_RECORDED_ALLOCATED >> 30))
293		phyblock = 0xFFFFFFFF;
294	else {
295		map = &UDF_SB(sb)->s_partmaps[partition];
296		/* map to sparable/physical partition desc */
297		phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
298			map->s_partition_num, ext_offset + offset);
299	}
300
301	brelse(epos.bh);
302	return phyblock;
303}
304
305uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
306				uint16_t partition, uint32_t offset)
307{
308	struct udf_sb_info *sbi = UDF_SB(sb);
309	struct udf_part_map *map;
310	struct udf_meta_data *mdata;
311	uint32_t retblk;
312	struct inode *inode;
313
314	udf_debug("READING from METADATA\n");
315
316	map = &sbi->s_partmaps[partition];
317	mdata = &map->s_type_specific.s_metadata;
318	inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe;
319
320	/* We shouldn't mount such media... */
321	BUG_ON(!inode);
322	retblk = udf_try_read_meta(inode, block, partition, offset);
323	if (retblk == 0xFFFFFFFF && mdata->s_metadata_fe) {
324		udf_warn(sb, "error reading from METADATA, trying to read from MIRROR\n");
325		if (!(mdata->s_flags & MF_MIRROR_FE_LOADED)) {
326			mdata->s_mirror_fe = udf_find_metadata_inode_efe(sb,
327				mdata->s_mirror_file_loc, map->s_partition_num);
328			mdata->s_flags |= MF_MIRROR_FE_LOADED;
329		}
330
331		inode = mdata->s_mirror_fe;
332		if (!inode)
333			return 0xFFFFFFFF;
334		retblk = udf_try_read_meta(inode, block, partition, offset);
335	}
336
337	return retblk;
338}
339