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1/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
4
5#include <linux/string.h>
6#include <linux/random.h>
7#include <linux/time.h>
8#include "reiserfs.h"
9
10// find where objectid map starts
11#define objectid_map(s,rs) (old_format_only (s) ? \
12 (__le32 *)((struct reiserfs_super_block_v1 *)(rs) + 1) :\
13 (__le32 *)((rs) + 1))
14
15#ifdef CONFIG_REISERFS_CHECK
16
17static void check_objectid_map(struct super_block *s, __le32 * map)
18{
19 if (le32_to_cpu(map[0]) != 1)
20 reiserfs_panic(s, "vs-15010", "map corrupted: %lx",
21 (long unsigned int)le32_to_cpu(map[0]));
22
23 // FIXME: add something else here
24}
25
26#else
27static void check_objectid_map(struct super_block *s, __le32 * map)
28{;
29}
30#endif
31
32/* When we allocate objectids we allocate the first unused objectid.
33 Each sequence of objectids in use (the odd sequences) is followed
34 by a sequence of objectids not in use (the even sequences). We
35 only need to record the last objectid in each of these sequences
36 (both the odd and even sequences) in order to fully define the
37 boundaries of the sequences. A consequence of allocating the first
38 objectid not in use is that under most conditions this scheme is
39 extremely compact. The exception is immediately after a sequence
40 of operations which deletes a large number of objects of
41 non-sequential objectids, and even then it will become compact
42 again as soon as more objects are created. Note that many
43 interesting optimizations of layout could result from complicating
44 objectid assignment, but we have deferred making them for now. */
45
46/* get unique object identifier */
47__u32 reiserfs_get_unused_objectid(struct reiserfs_transaction_handle *th)
48{
49 struct super_block *s = th->t_super;
50 struct reiserfs_super_block *rs = SB_DISK_SUPER_BLOCK(s);
51 __le32 *map = objectid_map(s, rs);
52 __u32 unused_objectid;
53
54 BUG_ON(!th->t_trans_id);
55
56 check_objectid_map(s, map);
57
58 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
59 /* comment needed -Hans */
60 unused_objectid = le32_to_cpu(map[1]);
61 if (unused_objectid == U32_MAX) {
62 reiserfs_warning(s, "reiserfs-15100", "no more object ids");
63 reiserfs_restore_prepared_buffer(s, SB_BUFFER_WITH_SB(s));
64 return 0;
65 }
66
67 /* This incrementation allocates the first unused objectid. That
68 is to say, the first entry on the objectid map is the first
69 unused objectid, and by incrementing it we use it. See below
70 where we check to see if we eliminated a sequence of unused
71 objectids.... */
72 map[1] = cpu_to_le32(unused_objectid + 1);
73
74 /* Now we check to see if we eliminated the last remaining member of
75 the first even sequence (and can eliminate the sequence by
76 eliminating its last objectid from oids), and can collapse the
77 first two odd sequences into one sequence. If so, then the net
78 result is to eliminate a pair of objectids from oids. We do this
79 by shifting the entire map to the left. */
80 if (sb_oid_cursize(rs) > 2 && map[1] == map[2]) {
81 memmove(map + 1, map + 3,
82 (sb_oid_cursize(rs) - 3) * sizeof(__u32));
83 set_sb_oid_cursize(rs, sb_oid_cursize(rs) - 2);
84 }
85
86 journal_mark_dirty(th, s, SB_BUFFER_WITH_SB(s));
87 return unused_objectid;
88}
89
90/* makes object identifier unused */
91void reiserfs_release_objectid(struct reiserfs_transaction_handle *th,
92 __u32 objectid_to_release)
93{
94 struct super_block *s = th->t_super;
95 struct reiserfs_super_block *rs = SB_DISK_SUPER_BLOCK(s);
96 __le32 *map = objectid_map(s, rs);
97 int i = 0;
98
99 BUG_ON(!th->t_trans_id);
100 //return;
101 check_objectid_map(s, map);
102
103 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
104 journal_mark_dirty(th, s, SB_BUFFER_WITH_SB(s));
105
106 /* start at the beginning of the objectid map (i = 0) and go to
107 the end of it (i = disk_sb->s_oid_cursize). Linear search is
108 what we use, though it is possible that binary search would be
109 more efficient after performing lots of deletions (which is
110 when oids is large.) We only check even i's. */
111 while (i < sb_oid_cursize(rs)) {
112 if (objectid_to_release == le32_to_cpu(map[i])) {
113 /* This incrementation unallocates the objectid. */
114 //map[i]++;
115 le32_add_cpu(&map[i], 1);
116
117 /* Did we unallocate the last member of an odd sequence, and can shrink oids? */
118 if (map[i] == map[i + 1]) {
119 /* shrink objectid map */
120 memmove(map + i, map + i + 2,
121 (sb_oid_cursize(rs) - i -
122 2) * sizeof(__u32));
123 //disk_sb->s_oid_cursize -= 2;
124 set_sb_oid_cursize(rs, sb_oid_cursize(rs) - 2);
125
126 RFALSE(sb_oid_cursize(rs) < 2 ||
127 sb_oid_cursize(rs) > sb_oid_maxsize(rs),
128 "vs-15005: objectid map corrupted cur_size == %d (max == %d)",
129 sb_oid_cursize(rs), sb_oid_maxsize(rs));
130 }
131 return;
132 }
133
134 if (objectid_to_release > le32_to_cpu(map[i]) &&
135 objectid_to_release < le32_to_cpu(map[i + 1])) {
136 /* size of objectid map is not changed */
137 if (objectid_to_release + 1 == le32_to_cpu(map[i + 1])) {
138 //objectid_map[i+1]--;
139 le32_add_cpu(&map[i + 1], -1);
140 return;
141 }
142
143 /* JDM comparing two little-endian values for equality -- safe */
144 if (sb_oid_cursize(rs) == sb_oid_maxsize(rs)) {
145 /* objectid map must be expanded, but there is no space */
146 PROC_INFO_INC(s, leaked_oid);
147 return;
148 }
149
150 /* expand the objectid map */
151 memmove(map + i + 3, map + i + 1,
152 (sb_oid_cursize(rs) - i - 1) * sizeof(__u32));
153 map[i + 1] = cpu_to_le32(objectid_to_release);
154 map[i + 2] = cpu_to_le32(objectid_to_release + 1);
155 set_sb_oid_cursize(rs, sb_oid_cursize(rs) + 2);
156 return;
157 }
158 i += 2;
159 }
160
161 reiserfs_error(s, "vs-15011", "tried to free free object id (%lu)",
162 (long unsigned)objectid_to_release);
163}
164
165int reiserfs_convert_objectid_map_v1(struct super_block *s)
166{
167 struct reiserfs_super_block *disk_sb = SB_DISK_SUPER_BLOCK(s);
168 int cur_size = sb_oid_cursize(disk_sb);
169 int new_size = (s->s_blocksize - SB_SIZE) / sizeof(__u32) / 2 * 2;
170 int old_max = sb_oid_maxsize(disk_sb);
171 struct reiserfs_super_block_v1 *disk_sb_v1;
172 __le32 *objectid_map, *new_objectid_map;
173 int i;
174
175 disk_sb_v1 =
176 (struct reiserfs_super_block_v1 *)(SB_BUFFER_WITH_SB(s)->b_data);
177 objectid_map = (__le32 *) (disk_sb_v1 + 1);
178 new_objectid_map = (__le32 *) (disk_sb + 1);
179
180 if (cur_size > new_size) {
181 /* mark everyone used that was listed as free at the end of the objectid
182 ** map
183 */
184 objectid_map[new_size - 1] = objectid_map[cur_size - 1];
185 set_sb_oid_cursize(disk_sb, new_size);
186 }
187 /* move the smaller objectid map past the end of the new super */
188 for (i = new_size - 1; i >= 0; i--) {
189 objectid_map[i + (old_max - new_size)] = objectid_map[i];
190 }
191
192 /* set the max size so we don't overflow later */
193 set_sb_oid_maxsize(disk_sb, new_size);
194
195 /* Zero out label and generate random UUID */
196 memset(disk_sb->s_label, 0, sizeof(disk_sb->s_label));
197 generate_random_uuid(disk_sb->s_uuid);
198
199 /* finally, zero out the unused chunk of the new super */
200 memset(disk_sb->s_unused, 0, sizeof(disk_sb->s_unused));
201 return 0;
202}
1/*
2 * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3 */
4
5#include <linux/string.h>
6#include <linux/time.h>
7#include <linux/uuid.h>
8#include "reiserfs.h"
9
10/* find where objectid map starts */
11#define objectid_map(s,rs) (old_format_only (s) ? \
12 (__le32 *)((struct reiserfs_super_block_v1 *)(rs) + 1) :\
13 (__le32 *)((rs) + 1))
14
15#ifdef CONFIG_REISERFS_CHECK
16
17static void check_objectid_map(struct super_block *s, __le32 * map)
18{
19 if (le32_to_cpu(map[0]) != 1)
20 reiserfs_panic(s, "vs-15010", "map corrupted: %lx",
21 (long unsigned int)le32_to_cpu(map[0]));
22
23 /* FIXME: add something else here */
24}
25
26#else
27static void check_objectid_map(struct super_block *s, __le32 * map)
28{;
29}
30#endif
31
32/*
33 * When we allocate objectids we allocate the first unused objectid.
34 * Each sequence of objectids in use (the odd sequences) is followed
35 * by a sequence of objectids not in use (the even sequences). We
36 * only need to record the last objectid in each of these sequences
37 * (both the odd and even sequences) in order to fully define the
38 * boundaries of the sequences. A consequence of allocating the first
39 * objectid not in use is that under most conditions this scheme is
40 * extremely compact. The exception is immediately after a sequence
41 * of operations which deletes a large number of objects of
42 * non-sequential objectids, and even then it will become compact
43 * again as soon as more objects are created. Note that many
44 * interesting optimizations of layout could result from complicating
45 * objectid assignment, but we have deferred making them for now.
46 */
47
48/* get unique object identifier */
49__u32 reiserfs_get_unused_objectid(struct reiserfs_transaction_handle *th)
50{
51 struct super_block *s = th->t_super;
52 struct reiserfs_super_block *rs = SB_DISK_SUPER_BLOCK(s);
53 __le32 *map = objectid_map(s, rs);
54 __u32 unused_objectid;
55
56 BUG_ON(!th->t_trans_id);
57
58 check_objectid_map(s, map);
59
60 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
61 /* comment needed -Hans */
62 unused_objectid = le32_to_cpu(map[1]);
63 if (unused_objectid == U32_MAX) {
64 reiserfs_warning(s, "reiserfs-15100", "no more object ids");
65 reiserfs_restore_prepared_buffer(s, SB_BUFFER_WITH_SB(s));
66 return 0;
67 }
68
69 /*
70 * This incrementation allocates the first unused objectid. That
71 * is to say, the first entry on the objectid map is the first
72 * unused objectid, and by incrementing it we use it. See below
73 * where we check to see if we eliminated a sequence of unused
74 * objectids....
75 */
76 map[1] = cpu_to_le32(unused_objectid + 1);
77
78 /*
79 * Now we check to see if we eliminated the last remaining member of
80 * the first even sequence (and can eliminate the sequence by
81 * eliminating its last objectid from oids), and can collapse the
82 * first two odd sequences into one sequence. If so, then the net
83 * result is to eliminate a pair of objectids from oids. We do this
84 * by shifting the entire map to the left.
85 */
86 if (sb_oid_cursize(rs) > 2 && map[1] == map[2]) {
87 memmove(map + 1, map + 3,
88 (sb_oid_cursize(rs) - 3) * sizeof(__u32));
89 set_sb_oid_cursize(rs, sb_oid_cursize(rs) - 2);
90 }
91
92 journal_mark_dirty(th, SB_BUFFER_WITH_SB(s));
93 return unused_objectid;
94}
95
96/* makes object identifier unused */
97void reiserfs_release_objectid(struct reiserfs_transaction_handle *th,
98 __u32 objectid_to_release)
99{
100 struct super_block *s = th->t_super;
101 struct reiserfs_super_block *rs = SB_DISK_SUPER_BLOCK(s);
102 __le32 *map = objectid_map(s, rs);
103 int i = 0;
104
105 BUG_ON(!th->t_trans_id);
106 /*return; */
107 check_objectid_map(s, map);
108
109 reiserfs_prepare_for_journal(s, SB_BUFFER_WITH_SB(s), 1);
110 journal_mark_dirty(th, SB_BUFFER_WITH_SB(s));
111
112 /*
113 * start at the beginning of the objectid map (i = 0) and go to
114 * the end of it (i = disk_sb->s_oid_cursize). Linear search is
115 * what we use, though it is possible that binary search would be
116 * more efficient after performing lots of deletions (which is
117 * when oids is large.) We only check even i's.
118 */
119 while (i < sb_oid_cursize(rs)) {
120 if (objectid_to_release == le32_to_cpu(map[i])) {
121 /* This incrementation unallocates the objectid. */
122 le32_add_cpu(&map[i], 1);
123
124 /*
125 * Did we unallocate the last member of an
126 * odd sequence, and can shrink oids?
127 */
128 if (map[i] == map[i + 1]) {
129 /* shrink objectid map */
130 memmove(map + i, map + i + 2,
131 (sb_oid_cursize(rs) - i -
132 2) * sizeof(__u32));
133 set_sb_oid_cursize(rs, sb_oid_cursize(rs) - 2);
134
135 RFALSE(sb_oid_cursize(rs) < 2 ||
136 sb_oid_cursize(rs) > sb_oid_maxsize(rs),
137 "vs-15005: objectid map corrupted cur_size == %d (max == %d)",
138 sb_oid_cursize(rs), sb_oid_maxsize(rs));
139 }
140 return;
141 }
142
143 if (objectid_to_release > le32_to_cpu(map[i]) &&
144 objectid_to_release < le32_to_cpu(map[i + 1])) {
145 /* size of objectid map is not changed */
146 if (objectid_to_release + 1 == le32_to_cpu(map[i + 1])) {
147 le32_add_cpu(&map[i + 1], -1);
148 return;
149 }
150
151 /*
152 * JDM comparing two little-endian values for
153 * equality -- safe
154 */
155 /*
156 * objectid map must be expanded, but
157 * there is no space
158 */
159 if (sb_oid_cursize(rs) == sb_oid_maxsize(rs)) {
160 PROC_INFO_INC(s, leaked_oid);
161 return;
162 }
163
164 /* expand the objectid map */
165 memmove(map + i + 3, map + i + 1,
166 (sb_oid_cursize(rs) - i - 1) * sizeof(__u32));
167 map[i + 1] = cpu_to_le32(objectid_to_release);
168 map[i + 2] = cpu_to_le32(objectid_to_release + 1);
169 set_sb_oid_cursize(rs, sb_oid_cursize(rs) + 2);
170 return;
171 }
172 i += 2;
173 }
174
175 reiserfs_error(s, "vs-15011", "tried to free free object id (%lu)",
176 (long unsigned)objectid_to_release);
177}
178
179int reiserfs_convert_objectid_map_v1(struct super_block *s)
180{
181 struct reiserfs_super_block *disk_sb = SB_DISK_SUPER_BLOCK(s);
182 int cur_size = sb_oid_cursize(disk_sb);
183 int new_size = (s->s_blocksize - SB_SIZE) / sizeof(__u32) / 2 * 2;
184 int old_max = sb_oid_maxsize(disk_sb);
185 struct reiserfs_super_block_v1 *disk_sb_v1;
186 __le32 *objectid_map;
187 int i;
188
189 disk_sb_v1 =
190 (struct reiserfs_super_block_v1 *)(SB_BUFFER_WITH_SB(s)->b_data);
191 objectid_map = (__le32 *) (disk_sb_v1 + 1);
192
193 if (cur_size > new_size) {
194 /*
195 * mark everyone used that was listed as free at
196 * the end of the objectid map
197 */
198 objectid_map[new_size - 1] = objectid_map[cur_size - 1];
199 set_sb_oid_cursize(disk_sb, new_size);
200 }
201 /* move the smaller objectid map past the end of the new super */
202 for (i = new_size - 1; i >= 0; i--) {
203 objectid_map[i + (old_max - new_size)] = objectid_map[i];
204 }
205
206 /* set the max size so we don't overflow later */
207 set_sb_oid_maxsize(disk_sb, new_size);
208
209 /* Zero out label and generate random UUID */
210 memset(disk_sb->s_label, 0, sizeof(disk_sb->s_label));
211 generate_random_uuid(disk_sb->s_uuid);
212
213 /* finally, zero out the unused chunk of the new super */
214 memset(disk_sb->s_unused, 0, sizeof(disk_sb->s_unused));
215 return 0;
216}