// SPDX-License-Identifier: GPL-2.0-only/* * 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 int nr_bits;	void *context;}; static int pack_bits(uint32_t index, void *value, void *context){	int r;	struct packer_context *p = context;	unsigned int 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 int 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 int 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 int 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 int 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); /*----------------------------------------------------------------*/