318 lines
6.9 KiB
C
318 lines
6.9 KiB
C
/*
|
|
* Copyright (C) 2012 Red Hat, Inc.
|
|
*
|
|
* This file is released under the GPL.
|
|
*/
|
|
|
|
#include "dm-bitset.h"
|
|
#include "dm-transaction-manager.h"
|
|
|
|
#include <linux/export.h>
|
|
#include <linux/device-mapper.h>
|
|
|
|
#define DM_MSG_PREFIX "bitset"
|
|
#define BITS_PER_ARRAY_ENTRY 64
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
static struct dm_btree_value_type bitset_bvt = {
|
|
.context = NULL,
|
|
.size = sizeof(__le64),
|
|
.inc = NULL,
|
|
.dec = NULL,
|
|
.equal = NULL,
|
|
};
|
|
|
|
/*----------------------------------------------------------------*/
|
|
|
|
void dm_disk_bitset_init(struct dm_transaction_manager *tm,
|
|
struct dm_disk_bitset *info)
|
|
{
|
|
dm_array_info_init(&info->array_info, tm, &bitset_bvt);
|
|
info->current_index_set = false;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_disk_bitset_init);
|
|
|
|
int dm_bitset_empty(struct dm_disk_bitset *info, dm_block_t *root)
|
|
{
|
|
return dm_array_empty(&info->array_info, root);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_empty);
|
|
|
|
struct packer_context {
|
|
bit_value_fn fn;
|
|
unsigned nr_bits;
|
|
void *context;
|
|
};
|
|
|
|
static int pack_bits(uint32_t index, void *value, void *context)
|
|
{
|
|
int r;
|
|
struct packer_context *p = context;
|
|
unsigned bit, nr = min(64u, p->nr_bits - (index * 64));
|
|
uint64_t word = 0;
|
|
bool bv;
|
|
|
|
for (bit = 0; bit < nr; bit++) {
|
|
r = p->fn(index * 64 + bit, &bv, p->context);
|
|
if (r)
|
|
return r;
|
|
|
|
if (bv)
|
|
set_bit(bit, (unsigned long *) &word);
|
|
else
|
|
clear_bit(bit, (unsigned long *) &word);
|
|
}
|
|
|
|
*((__le64 *) value) = cpu_to_le64(word);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int dm_bitset_new(struct dm_disk_bitset *info, dm_block_t *root,
|
|
uint32_t size, bit_value_fn fn, void *context)
|
|
{
|
|
struct packer_context p;
|
|
p.fn = fn;
|
|
p.nr_bits = size;
|
|
p.context = context;
|
|
|
|
return dm_array_new(&info->array_info, root, dm_div_up(size, 64), pack_bits, &p);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_new);
|
|
|
|
int dm_bitset_resize(struct dm_disk_bitset *info, dm_block_t root,
|
|
uint32_t old_nr_entries, uint32_t new_nr_entries,
|
|
bool default_value, dm_block_t *new_root)
|
|
{
|
|
uint32_t old_blocks = dm_div_up(old_nr_entries, BITS_PER_ARRAY_ENTRY);
|
|
uint32_t new_blocks = dm_div_up(new_nr_entries, BITS_PER_ARRAY_ENTRY);
|
|
__le64 value = default_value ? cpu_to_le64(~0) : cpu_to_le64(0);
|
|
|
|
__dm_bless_for_disk(&value);
|
|
return dm_array_resize(&info->array_info, root, old_blocks, new_blocks,
|
|
&value, new_root);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_resize);
|
|
|
|
int dm_bitset_del(struct dm_disk_bitset *info, dm_block_t root)
|
|
{
|
|
return dm_array_del(&info->array_info, root);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_del);
|
|
|
|
int dm_bitset_flush(struct dm_disk_bitset *info, dm_block_t root,
|
|
dm_block_t *new_root)
|
|
{
|
|
int r;
|
|
__le64 value;
|
|
|
|
if (!info->current_index_set || !info->dirty)
|
|
return 0;
|
|
|
|
value = cpu_to_le64(info->current_bits);
|
|
|
|
__dm_bless_for_disk(&value);
|
|
r = dm_array_set_value(&info->array_info, root, info->current_index,
|
|
&value, new_root);
|
|
if (r)
|
|
return r;
|
|
|
|
info->current_index_set = false;
|
|
info->dirty = false;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_flush);
|
|
|
|
static int read_bits(struct dm_disk_bitset *info, dm_block_t root,
|
|
uint32_t array_index)
|
|
{
|
|
int r;
|
|
__le64 value;
|
|
|
|
r = dm_array_get_value(&info->array_info, root, array_index, &value);
|
|
if (r)
|
|
return r;
|
|
|
|
info->current_bits = le64_to_cpu(value);
|
|
info->current_index_set = true;
|
|
info->current_index = array_index;
|
|
info->dirty = false;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int get_array_entry(struct dm_disk_bitset *info, dm_block_t root,
|
|
uint32_t index, dm_block_t *new_root)
|
|
{
|
|
int r;
|
|
unsigned array_index = index / BITS_PER_ARRAY_ENTRY;
|
|
|
|
if (info->current_index_set) {
|
|
if (info->current_index == array_index)
|
|
return 0;
|
|
|
|
r = dm_bitset_flush(info, root, new_root);
|
|
if (r)
|
|
return r;
|
|
}
|
|
|
|
return read_bits(info, root, array_index);
|
|
}
|
|
|
|
int dm_bitset_set_bit(struct dm_disk_bitset *info, dm_block_t root,
|
|
uint32_t index, dm_block_t *new_root)
|
|
{
|
|
int r;
|
|
unsigned b = index % BITS_PER_ARRAY_ENTRY;
|
|
|
|
r = get_array_entry(info, root, index, new_root);
|
|
if (r)
|
|
return r;
|
|
|
|
set_bit(b, (unsigned long *) &info->current_bits);
|
|
info->dirty = true;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_set_bit);
|
|
|
|
int dm_bitset_clear_bit(struct dm_disk_bitset *info, dm_block_t root,
|
|
uint32_t index, dm_block_t *new_root)
|
|
{
|
|
int r;
|
|
unsigned b = index % BITS_PER_ARRAY_ENTRY;
|
|
|
|
r = get_array_entry(info, root, index, new_root);
|
|
if (r)
|
|
return r;
|
|
|
|
clear_bit(b, (unsigned long *) &info->current_bits);
|
|
info->dirty = true;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_clear_bit);
|
|
|
|
int dm_bitset_test_bit(struct dm_disk_bitset *info, dm_block_t root,
|
|
uint32_t index, dm_block_t *new_root, bool *result)
|
|
{
|
|
int r;
|
|
unsigned b = index % BITS_PER_ARRAY_ENTRY;
|
|
|
|
r = get_array_entry(info, root, index, new_root);
|
|
if (r)
|
|
return r;
|
|
|
|
*result = test_bit(b, (unsigned long *) &info->current_bits);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_test_bit);
|
|
|
|
static int cursor_next_array_entry(struct dm_bitset_cursor *c)
|
|
{
|
|
int r;
|
|
__le64 *value;
|
|
|
|
r = dm_array_cursor_next(&c->cursor);
|
|
if (r)
|
|
return r;
|
|
|
|
dm_array_cursor_get_value(&c->cursor, (void **) &value);
|
|
c->array_index++;
|
|
c->bit_index = 0;
|
|
c->current_bits = le64_to_cpu(*value);
|
|
return 0;
|
|
}
|
|
|
|
int dm_bitset_cursor_begin(struct dm_disk_bitset *info,
|
|
dm_block_t root, uint32_t nr_entries,
|
|
struct dm_bitset_cursor *c)
|
|
{
|
|
int r;
|
|
__le64 *value;
|
|
|
|
if (!nr_entries)
|
|
return -ENODATA;
|
|
|
|
c->info = info;
|
|
c->entries_remaining = nr_entries;
|
|
|
|
r = dm_array_cursor_begin(&info->array_info, root, &c->cursor);
|
|
if (r)
|
|
return r;
|
|
|
|
dm_array_cursor_get_value(&c->cursor, (void **) &value);
|
|
c->array_index = 0;
|
|
c->bit_index = 0;
|
|
c->current_bits = le64_to_cpu(*value);
|
|
|
|
return r;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_cursor_begin);
|
|
|
|
void dm_bitset_cursor_end(struct dm_bitset_cursor *c)
|
|
{
|
|
return dm_array_cursor_end(&c->cursor);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_cursor_end);
|
|
|
|
int dm_bitset_cursor_next(struct dm_bitset_cursor *c)
|
|
{
|
|
int r = 0;
|
|
|
|
if (!c->entries_remaining)
|
|
return -ENODATA;
|
|
|
|
c->entries_remaining--;
|
|
if (++c->bit_index > 63)
|
|
r = cursor_next_array_entry(c);
|
|
|
|
return r;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_cursor_next);
|
|
|
|
int dm_bitset_cursor_skip(struct dm_bitset_cursor *c, uint32_t count)
|
|
{
|
|
int r;
|
|
__le64 *value;
|
|
uint32_t nr_array_skip;
|
|
uint32_t remaining_in_word = 64 - c->bit_index;
|
|
|
|
if (c->entries_remaining < count)
|
|
return -ENODATA;
|
|
|
|
if (count < remaining_in_word) {
|
|
c->bit_index += count;
|
|
c->entries_remaining -= count;
|
|
return 0;
|
|
|
|
} else {
|
|
c->entries_remaining -= remaining_in_word;
|
|
count -= remaining_in_word;
|
|
}
|
|
|
|
nr_array_skip = (count / 64) + 1;
|
|
r = dm_array_cursor_skip(&c->cursor, nr_array_skip);
|
|
if (r)
|
|
return r;
|
|
|
|
dm_array_cursor_get_value(&c->cursor, (void **) &value);
|
|
c->entries_remaining -= count;
|
|
c->array_index += nr_array_skip;
|
|
c->bit_index = count & 63;
|
|
c->current_bits = le64_to_cpu(*value);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_cursor_skip);
|
|
|
|
bool dm_bitset_cursor_get_value(struct dm_bitset_cursor *c)
|
|
{
|
|
return test_bit(c->bit_index, (unsigned long *) &c->current_bits);
|
|
}
|
|
EXPORT_SYMBOL_GPL(dm_bitset_cursor_get_value);
|
|
|
|
/*----------------------------------------------------------------*/
|