#include <stdlib.h>
#include <string.h>
#include <assert.h>
+#include <err.h>
#include "logging.h"
-struct tdb_layout *new_tdb_layout(void)
+struct tdb_layout *new_tdb_layout(const char *filename)
{
struct tdb_layout *layout = malloc(sizeof(*layout));
+ layout->filename = filename;
layout->num_elems = 0;
layout->elem = NULL;
- layout->htable = -1;
return layout;
}
add(layout, elem);
}
-void tdb_layout_add_hashtable(struct tdb_layout *layout,
- unsigned int hash_bits,
- tdb_len_t extra)
-{
- union tdb_layout_elem elem;
- elem.base.type = HASHTABLE;
- elem.hashtable.hash_bits = hash_bits;
- elem.hashtable.extra = extra;
- assert(layout->htable == -1U);
- layout->htable = layout->num_elems;
- add(layout, elem);
-}
-
static tdb_len_t free_record_len(tdb_len_t len)
{
return sizeof(struct tdb_used_record) + len;
static tdb_len_t hashtable_len(struct tle_hashtable *htable)
{
return sizeof(struct tdb_used_record)
- + (sizeof(tdb_off_t) << htable->hash_bits);
+ + (sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS)
+ + htable->extra;
}
static tdb_len_t zone_header_len(struct tle_zone *zone)
struct tle_hashtable *htable)
{
struct tdb_used_record *u = mem;
- tdb_len_t len = sizeof(tdb_off_t) << htable->hash_bits;
+ tdb_len_t len = sizeof(tdb_off_t) << TDB_SUBLEVEL_HASH_BITS;
set_header(tdb, u, 0, len, len + htable->extra, 0,
last_zone->zone_bits);
sizeof(struct tdb_used_record) + elen);
}
+static tdb_off_t hbucket_off(tdb_off_t group_start, unsigned ingroup)
+{
+ return group_start
+ + (ingroup % (1 << TDB_HASH_GROUP_BITS)) * sizeof(tdb_off_t);
+}
+
+/* Get bits from a value. */
+static uint32_t bits(uint64_t val, unsigned start, unsigned num)
+{
+ assert(num <= 32);
+ return (val >> start) & ((1U << num) - 1);
+}
+
+/* We take bits from the top: that way we can lock whole sections of the hash
+ * by using lock ranges. */
+static uint32_t use_bits(uint64_t h, unsigned num, unsigned *used)
+{
+ *used += num;
+ return bits(h, 64 - *used, num);
+}
+
+static tdb_off_t encode_offset(tdb_off_t new_off, unsigned bucket,
+ uint64_t h)
+{
+ return bucket
+ | new_off
+ | ((uint64_t)bits(h, 64 - TDB_OFF_UPPER_STEAL_EXTRA,
+ TDB_OFF_UPPER_STEAL_EXTRA)
+ << TDB_OFF_HASH_EXTRA_BIT);
+}
+
+/* FIXME: Our hash table handling here is primitive: we don't expand! */
static void add_to_hashtable(struct tdb_context *tdb,
tdb_off_t eoff,
struct tdb_data key)
{
- uint64_t hash = tdb_hash(tdb, key.dptr, key.dsize);
- tdb_off_t hoff;
+ uint64_t h = tdb_hash(tdb, key.dptr, key.dsize);
+ tdb_off_t b_off, group_start;
+ unsigned i, group, in_group;
+ unsigned used = 0;
- while (tdb_read_off(tdb, hoff = hash_off(tdb, hash)) != 0)
- hash++;
+ group = use_bits(h, TDB_TOPLEVEL_HASH_BITS-TDB_HASH_GROUP_BITS, &used);
+ in_group = use_bits(h, TDB_HASH_GROUP_BITS, &used);
- tdb_write_off(tdb, hoff, eoff);
+ group_start = offsetof(struct tdb_header, hashtable)
+ + group * (sizeof(tdb_off_t) << TDB_HASH_GROUP_BITS);
+
+ for (i = 0; i < (1 << TDB_HASH_GROUP_BITS); i++) {
+ unsigned bucket = (in_group + i) % (1 << TDB_HASH_GROUP_BITS);
+
+ b_off = hbucket_off(group_start, bucket);
+ if (tdb_read_off(tdb, b_off) == 0) {
+ tdb_write_off(tdb, b_off,
+ encode_offset(eoff, bucket, h));
+ return;
+ }
+ }
+ abort();
}
/* FIXME: Support TDB_CONVERT */
unsigned int i;
tdb_off_t off, len;
tdb_len_t zone_left;
- struct tdb_header *hdr;
char *mem;
struct tdb_context *tdb;
struct tle_zone *last_zone = NULL;
- assert(layout->htable != -1U);
assert(layout->elem[0].base.type == ZONE);
zone_left = 0;
case HASHTABLE:
len = hashtable_len(&e->hashtable);
break;
+ default:
+ abort();
}
off += len;
assert(zone_left >= len);
zone_left -= len;
}
- /* Fill final zone with free record. */
- if (zone_left != 0) {
- tdb_layout_add_free(layout,
- zone_left
- - sizeof(struct tdb_used_record));
- layout->elem[layout->num_elems-1].base.off = off;
- off += zone_left;
- }
-
- mem = malloc(off+1);
+ mem = malloc(off);
/* Now populate our header, cribbing from a real TDB header. */
tdb = tdb_open(NULL, TDB_INTERNAL, O_RDWR, 0, &tap_log_attr);
- hdr = (void *)mem;
- *hdr = tdb->header;
- hdr->v.generation++;
- hdr->v.hash_bits = layout->elem[layout->htable].hashtable.hash_bits;
- hdr->v.hash_off = layout->elem[layout->htable].base.off
- + sizeof(struct tdb_used_record);
+ memcpy(mem, tdb->map_ptr, sizeof(struct tdb_header));
/* Mug the tdb we have to make it use this. */
free(tdb->map_ptr);
tdb->map_ptr = mem;
- tdb->map_size = off+1;
- header_changed(tdb);
+ tdb->map_size = off;
for (i = 0; i < layout->num_elems; i++) {
union tdb_layout_elem *e = &layout->elem[i];
}
}
- /* Write tailer. */
- ((uint8_t *)tdb->map_ptr)[tdb->map_size-1] = last_zone->zone_bits;
+ /* Get physical if they asked for it. */
+ if (layout->filename) {
+ int fd = open(layout->filename, O_WRONLY|O_TRUNC|O_CREAT,
+ 0600);
+ if (fd < 0)
+ err(1, "opening %s for writing", layout->filename);
+ if (write(fd, tdb->map_ptr, tdb->map_size) != tdb->map_size)
+ err(1, "writing %s", layout->filename);
+ close(fd);
+ tdb_close(tdb);
+ /* NOMMAP is for lockcheck. */
+ tdb = tdb_open(layout->filename, TDB_NOMMAP, O_RDWR, 0,
+ &tap_log_attr);
+ }
+
return tdb;
}