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/buffer_head.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: "
36			  "invalid partition\n", 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 "
63			  "(%d max %d)\n", 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
163	for (i = 0; i < sbi->s_partitions; i++) {
164		struct udf_part_map *map = &sbi->s_partmaps[i];
165		if (old_block > map->s_partition_root &&
166		    old_block < map->s_partition_root + map->s_partition_len) {
167			sdata = &map->s_type_specific.s_sparing;
168			packet = (old_block - map->s_partition_root) &
169						~(sdata->s_packet_len - 1);
170
171			for (j = 0; j < 4; j++)
172				if (sdata->s_spar_map[j] != NULL) {
173					st = (struct sparingTable *)
174						sdata->s_spar_map[j]->b_data;
175					break;
176				}
177
178			if (!st)
179				return 1;
180
181			reallocationTableLen =
182					le16_to_cpu(st->reallocationTableLen);
183			for (k = 0; k < reallocationTableLen; k++) {
184				struct sparingEntry *entry = &st->mapEntry[k];
185				u32 origLoc = le32_to_cpu(entry->origLocation);
186
187				if (origLoc == 0xFFFFFFFF) {
188					for (; j < 4; j++) {
189						int len;
190						bh = sdata->s_spar_map[j];
191						if (!bh)
192							continue;
193
194						st = (struct sparingTable *)
195								bh->b_data;
196						entry->origLocation =
197							cpu_to_le32(packet);
198						len =
199						  sizeof(struct sparingTable) +
200						  reallocationTableLen *
201						  sizeof(struct sparingEntry);
202						udf_update_tag((char *)st, len);
203						mark_buffer_dirty(bh);
204					}
205					*new_block = le32_to_cpu(
206							entry->mappedLocation) +
207						     ((old_block -
208							map->s_partition_root) &
209						     (sdata->s_packet_len - 1));
210					return 0;
211				} else if (origLoc == packet) {
212					*new_block = le32_to_cpu(
213							entry->mappedLocation) +
214						     ((old_block -
215							map->s_partition_root) &
216						     (sdata->s_packet_len - 1));
217					return 0;
218				} else if (origLoc > packet)
219					break;
220			}
221
222			for (l = k; l < reallocationTableLen; l++) {
223				struct sparingEntry *entry = &st->mapEntry[l];
224				u32 origLoc = le32_to_cpu(entry->origLocation);
225
226				if (origLoc != 0xFFFFFFFF)
227					continue;
228
229				for (; j < 4; j++) {
230					bh = sdata->s_spar_map[j];
231					if (!bh)
232						continue;
233
234					st = (struct sparingTable *)bh->b_data;
235					mapEntry = st->mapEntry[l];
236					mapEntry.origLocation =
237							cpu_to_le32(packet);
238					memmove(&st->mapEntry[k + 1],
239						&st->mapEntry[k],
240						(l - k) *
241						sizeof(struct sparingEntry));
242					st->mapEntry[k] = mapEntry;
243					udf_update_tag((char *)st,
244						sizeof(struct sparingTable) +
245						reallocationTableLen *
246						sizeof(struct sparingEntry));
247					mark_buffer_dirty(bh);
248				}
249				*new_block =
250					le32_to_cpu(
251					      st->mapEntry[k].mappedLocation) +
252					((old_block - map->s_partition_root) &
253					 (sdata->s_packet_len - 1));
254				return 0;
255			}
256
257			return 1;
258		} /* if old_block */
259	}
260
261	if (i == sbi->s_partitions) {
262		/* outside of partitions */
263		/* for now, fail =) */
264		return 1;
265	}
266
267	return 0;
268}
269
270static uint32_t udf_try_read_meta(struct inode *inode, uint32_t block,
271					uint16_t partition, uint32_t offset)
272{
273	struct super_block *sb = inode->i_sb;
274	struct udf_part_map *map;
275	struct kernel_lb_addr eloc;
276	uint32_t elen;
277	sector_t ext_offset;
278	struct extent_position epos = {};
279	uint32_t phyblock;
280
281	if (inode_bmap(inode, block, &epos, &eloc, &elen, &ext_offset) !=
282						(EXT_RECORDED_ALLOCATED >> 30))
283		phyblock = 0xFFFFFFFF;
284	else {
285		map = &UDF_SB(sb)->s_partmaps[partition];
286		/* map to sparable/physical partition desc */
287		phyblock = udf_get_pblock(sb, eloc.logicalBlockNum,
288			map->s_partition_num, ext_offset + offset);
289	}
290
291	brelse(epos.bh);
292	return phyblock;
293}
294
295uint32_t udf_get_pblock_meta25(struct super_block *sb, uint32_t block,
296				uint16_t partition, uint32_t offset)
297{
298	struct udf_sb_info *sbi = UDF_SB(sb);
299	struct udf_part_map *map;
300	struct udf_meta_data *mdata;
301	uint32_t retblk;
302	struct inode *inode;
303
304	udf_debug("READING from METADATA\n");
305
306	map = &sbi->s_partmaps[partition];
307	mdata = &map->s_type_specific.s_metadata;
308	inode = mdata->s_metadata_fe ? : mdata->s_mirror_fe;
309
310	/* We shouldn't mount such media... */
311	BUG_ON(!inode);
312	retblk = udf_try_read_meta(inode, block, partition, offset);
313	if (retblk == 0xFFFFFFFF) {
314		udf_warning(sb, __func__, "error reading from METADATA, "
315			"trying to read from MIRROR");
316		inode = mdata->s_mirror_fe;
317		if (!inode)
318			return 0xFFFFFFFF;
319		retblk = udf_try_read_meta(inode, block, partition, offset);
320	}
321
322	return retblk;
323}
324