1 /* TDB tools to create various canned database layouts. */
8 struct tdb_layout *new_tdb_layout(void)
10 struct tdb_layout *layout = malloc(sizeof(*layout));
11 layout->num_elems = 0;
16 static void add(struct tdb_layout *layout, union tdb_layout_elem elem)
18 layout->elem = realloc(layout->elem,
19 sizeof(layout->elem[0])
20 * (layout->num_elems+1));
21 layout->elem[layout->num_elems++] = elem;
24 void tdb_layout_add_zone(struct tdb_layout *layout,
25 unsigned int zone_bits,
28 union tdb_layout_elem elem;
30 tdb_layout_add_free(layout, 0);
31 elem.base.type = ZONE;
32 elem.zone.zone_bits = zone_bits;
36 void tdb_layout_add_free(struct tdb_layout *layout, tdb_len_t len)
38 union tdb_layout_elem elem;
39 elem.base.type = FREE;
44 static struct tdb_data dup_key(struct tdb_data key)
47 ret.dsize = key.dsize;
48 ret.dptr = malloc(ret.dsize);
49 memcpy(ret.dptr, key.dptr, ret.dsize);
53 void tdb_layout_add_used(struct tdb_layout *layout,
54 TDB_DATA key, TDB_DATA data,
57 union tdb_layout_elem elem;
58 elem.base.type = DATA;
59 elem.used.key = dup_key(key);
60 elem.used.data = dup_key(data);
61 elem.used.extra = extra;
65 static tdb_len_t free_record_len(tdb_len_t len)
67 return sizeof(struct tdb_used_record) + len;
70 static tdb_len_t data_record_len(struct tle_used *used)
73 len = sizeof(struct tdb_used_record)
74 + used->key.dsize + used->data.dsize + used->extra;
75 assert(len >= sizeof(struct tdb_free_record));
79 static tdb_len_t hashtable_len(struct tle_hashtable *htable)
81 return sizeof(struct tdb_used_record)
82 + (sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS)
86 static tdb_len_t zone_header_len(struct tle_zone *zone)
88 return sizeof(struct free_zone_header)
89 + sizeof(tdb_off_t) * (BUCKETS_FOR_ZONE(zone->zone_bits)+1);
92 static void set_free_record(void *mem, tdb_len_t len)
94 /* We do all the work in add_to_freetable */
97 static void set_data_record(void *mem, struct tdb_context *tdb,
98 struct tle_zone *last_zone,
99 struct tle_used *used)
101 struct tdb_used_record *u = mem;
103 set_header(tdb, u, used->key.dsize, used->data.dsize,
104 used->key.dsize + used->data.dsize + used->extra,
105 tdb_hash(tdb, used->key.dptr, used->key.dsize),
106 last_zone->zone_bits);
107 memcpy(u + 1, used->key.dptr, used->key.dsize);
108 memcpy((char *)(u + 1) + used->key.dsize,
109 used->data.dptr, used->data.dsize);
112 static void set_hashtable(void *mem, struct tdb_context *tdb,
113 struct tle_zone *last_zone,
114 struct tle_hashtable *htable)
116 struct tdb_used_record *u = mem;
117 tdb_len_t len = sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS;
119 set_header(tdb, u, 0, len, len + htable->extra, 0,
120 last_zone->zone_bits);
121 memset(u + 1, 0, len);
124 static void set_zone(void *mem, struct tdb_context *tdb,
125 struct tle_zone *zone)
127 struct free_zone_header *fz = mem;
128 memset(fz, 0, zone_header_len(zone));
129 fz->zone_bits = zone->zone_bits;
132 static void add_to_freetable(struct tdb_context *tdb,
133 struct tle_zone *last_zone,
137 add_free_record(tdb, last_zone->zone_bits, eoff,
138 sizeof(struct tdb_used_record) + elen);
141 static tdb_off_t hbucket_off(tdb_off_t group_start, unsigned ingroup)
144 + (ingroup % (1 << TDB_HASH_GROUP_BITS)) * sizeof(tdb_off_t);
147 /* Get bits from a value. */
148 static uint32_t bits(uint64_t val, unsigned start, unsigned num)
151 return (val >> start) & ((1U << num) - 1);
154 /* We take bits from the top: that way we can lock whole sections of the hash
155 * by using lock ranges. */
156 static uint32_t use_bits(uint64_t h, unsigned num, unsigned *used)
159 return bits(h, 64 - *used, num);
162 static tdb_off_t encode_offset(tdb_off_t new_off, unsigned bucket,
167 | ((uint64_t)bits(h, 64 - TDB_OFF_UPPER_STEAL_EXTRA,
168 TDB_OFF_UPPER_STEAL_EXTRA)
169 << TDB_OFF_HASH_EXTRA_BIT);
172 /* FIXME: Our hash table handling here is primitive: we don't expand! */
173 static void add_to_hashtable(struct tdb_context *tdb,
177 uint64_t h = tdb_hash(tdb, key.dptr, key.dsize);
178 tdb_off_t b_off, group_start;
179 unsigned i, group, in_group;
182 group = use_bits(h, TDB_TOPLEVEL_HASH_BITS-TDB_HASH_GROUP_BITS, &used);
183 in_group = use_bits(h, TDB_HASH_GROUP_BITS, &used);
185 group_start = offsetof(struct tdb_header, hashtable)
186 + group * (sizeof(tdb_off_t) << TDB_HASH_GROUP_BITS);
188 for (i = 0; i < (1 << TDB_HASH_GROUP_BITS); i++) {
189 unsigned bucket = (in_group + i) % (1 << TDB_HASH_GROUP_BITS);
191 b_off = hbucket_off(group_start, bucket);
192 if (tdb_read_off(tdb, b_off) == 0) {
193 tdb_write_off(tdb, b_off,
194 encode_offset(eoff, bucket, h));
201 /* FIXME: Support TDB_CONVERT */
202 struct tdb_context *tdb_layout_get(struct tdb_layout *layout)
208 struct tdb_context *tdb;
209 struct tle_zone *last_zone = NULL;
211 assert(layout->elem[0].base.type == ZONE);
214 off = sizeof(struct tdb_header);
216 /* First pass of layout: calc lengths */
217 for (i = 0; i < layout->num_elems; i++) {
218 union tdb_layout_elem *e = &layout->elem[i];
220 switch (e->base.type) {
222 assert(zone_left == 0);
223 len = zone_header_len(&e->zone);
224 zone_left = 1ULL << e->zone.zone_bits;
227 if (e->free.len == 0)
228 e->free.len = zone_left
229 - sizeof(struct tdb_used_record);
230 len = free_record_len(e->free.len);
233 len = data_record_len(&e->used);
236 len = hashtable_len(&e->hashtable);
240 assert(zone_left >= len);
244 /* Fill final zone with free record. */
245 if (zone_left != 0) {
246 tdb_layout_add_free(layout,
248 - sizeof(struct tdb_used_record));
249 layout->elem[layout->num_elems-1].base.off = off;
254 /* Now populate our header, cribbing from a real TDB header. */
255 tdb = tdb_open(NULL, TDB_INTERNAL, O_RDWR, 0, &tap_log_attr);
256 memcpy(mem, tdb->map_ptr, sizeof(struct tdb_header));
258 /* Mug the tdb we have to make it use this. */
261 tdb->map_size = off+1;
263 for (i = 0; i < layout->num_elems; i++) {
264 union tdb_layout_elem *e = &layout->elem[i];
265 switch (e->base.type) {
267 set_zone(mem + e->base.off, tdb, &e->zone);
268 last_zone = &e->zone;
271 set_free_record(mem + e->base.off, e->free.len);
274 set_data_record(mem + e->base.off, tdb, last_zone,
278 set_hashtable(mem + e->base.off, tdb, last_zone,
284 /* Now fill the free and hash tables. */
285 for (i = 0; i < layout->num_elems; i++) {
286 union tdb_layout_elem *e = &layout->elem[i];
287 switch (e->base.type) {
289 last_zone = &e->zone;
292 add_to_freetable(tdb, last_zone,
293 e->base.off, e->free.len);
296 add_to_hashtable(tdb, e->base.off, e->used.key);
304 ((uint8_t *)tdb->map_ptr)[tdb->map_size-1] = last_zone->zone_bits;