C++ BITS_TO_LONGS函數代碼示例

int mlx4_bitmap_init(struct mlx4_bitmap *bitmap, u32 num, u32 mask,
		     u32 reserved_bot, u32 reserved_top)
{
	/* num must be a power of 2 */
	if (num != roundup_pow_of_two(num))
		return -EINVAL;

	bitmap->last = 0;
	bitmap->top  = 0;
	bitmap->max  = num - reserved_top;
	bitmap->mask = mask;
	bitmap->reserved_top = reserved_top;
	spin_lock_init(&bitmap->lock);
	bitmap->table = kzalloc(BITS_TO_LONGS(bitmap->max) *
				sizeof (long), GFP_KERNEL);
	if (!bitmap->table)
		return -ENOMEM;

	bitmap_set(bitmap->table, 0, reserved_bot);

	return 0;
}

static __init struct cma *cma_create_area(unsigned long base_pfn,
				     unsigned long carved_out_count,
				     unsigned long count)
{
	int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
	struct cma *cma;
	int ret = -ENOMEM;

	pr_debug("%s(base %08lx, count %lx)\n", __func__, base_pfn, count);

	cma = kzalloc(sizeof *cma, GFP_KERNEL);
	if (!cma)
		return ERR_PTR(-ENOMEM);

	cma->base_pfn = base_pfn;
	cma->count = count;
	cma->free_count = count;
	cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
#ifdef CMA_NO_MIGRATION
	cma->isolated = true;
#endif

	if (!cma->bitmap)
		goto no_mem;

	ret = cma_activate_area(base_pfn, carved_out_count);
	if (ret)
		goto error;

	pr_debug("%s: returned %p\n", __func__, (void *)cma);
	return cma;

error:
	kfree(cma->bitmap);
no_mem:
	kfree(cma);
	return ERR_PTR(ret);
}

static int __init cma_activate_area(struct cma *cma)
{
	int bitmap_size = BITS_TO_LONGS(cma->count) * sizeof(long);
	unsigned long base_pfn = cma->base_pfn, pfn = base_pfn;
	unsigned i = cma->count >> pageblock_order;
	struct zone *zone;

	cma->bitmap = kzalloc(bitmap_size, GFP_KERNEL);

	if (!cma->bitmap)
		return -ENOMEM;

	WARN_ON_ONCE(!pfn_valid(pfn));
	zone = page_zone(pfn_to_page(pfn));

	do {
		unsigned j;
		base_pfn = pfn;
		for (j = pageblock_nr_pages; j; --j, pfn++) {
			WARN_ON_ONCE(!pfn_valid(pfn));
			/*
			 * alloc_contig_range requires the pfn range
			 * specified to be in the same zone. Make this
			 * simple by forcing the entire CMA resv range
			 * to be in the same zone.
			 */
			if (page_zone(pfn_to_page(pfn)) != zone)
				goto err;
		}
		init_cma_reserved_pageblock(pfn_to_page(base_pfn));
	} while (--i);

	return 0;

err:
	kfree(cma->bitmap);
	return -EINVAL;
}

static int bits_to_user(unsigned long *bits, unsigned int maxbit,
       unsigned int maxlen, void __user *p, int compat)
{
   int len, i;
   if (compat) {
     len = BITS_TO_LONGS_COMPAT(maxbit) * sizeof(compat_long_t);
     if (len > maxlen)
       len = maxlen;
     for (i = 0; i < len / sizeof(compat_long_t); i++)
       if (copy_to_user((compat_long_t __user *) p + i,
            (compat_long_t *) bits +
             i + 1 - ((i % 2) << 1),
            sizeof(compat_long_t)))
         return -EFAULT;
   } else {
     len = BITS_TO_LONGS(maxbit) * sizeof(long);
     if (len > maxlen)
       len = maxlen;
     if (copy_to_user(p, bits, len))
       return -EFAULT;
   }
   return len;
}

void
i915_gem_object_save_bit_17_swizzle(struct drm_i915_gem_object *obj)
{
	int page_count = obj->base.size >> PAGE_SHIFT;
	int i;

	if (obj->bit_17 == NULL) {
		obj->bit_17 = kmalloc(BITS_TO_LONGS(page_count) *
					   sizeof(long), GFP_KERNEL);
		if (obj->bit_17 == NULL) {
			DRM_ERROR("Failed to allocate memory for bit 17 "
				  "record\n");
			return;
		}
	}

	for (i = 0; i < page_count; i++) {
		if (page_to_phys(obj->pages[i]) & (1 << 17))
			__set_bit(i, obj->bit_17);
		else
			__clear_bit(i, obj->bit_17);
	}
}

int ath10k_htt_tx_alloc(struct ath10k_htt *htt)
{
	struct ath10k *ar = htt->ar;

	spin_lock_init(&htt->tx_lock);

	if (test_bit(ATH10K_FW_FEATURE_WMI_10X, htt->ar->fw_features))
		htt->max_num_pending_tx = TARGET_10X_NUM_MSDU_DESC;
	else
		htt->max_num_pending_tx = TARGET_NUM_MSDU_DESC;

	ath10k_dbg(ar, ATH10K_DBG_BOOT, "htt tx max num pending tx %d\n",
		   htt->max_num_pending_tx);

	htt->pending_tx = kzalloc(sizeof(*htt->pending_tx) *
				  htt->max_num_pending_tx, GFP_KERNEL);
	if (!htt->pending_tx)
		return -ENOMEM;

	htt->used_msdu_ids = kzalloc(sizeof(unsigned long) *
				     BITS_TO_LONGS(htt->max_num_pending_tx),
				     GFP_KERNEL);
	if (!htt->used_msdu_ids) {
		kfree(htt->pending_tx);
		return -ENOMEM;
	}

	htt->tx_pool = dma_pool_create("ath10k htt tx pool", htt->ar->dev,
				       sizeof(struct ath10k_htt_txbuf), 4, 0);
	if (!htt->tx_pool) {
		kfree(htt->used_msdu_ids);
		kfree(htt->pending_tx);
		return -ENOMEM;
	}

	return 0;
}

static int intel_setup_irq_remapping(struct intel_iommu *iommu, int mode)
{
	struct ir_table *ir_table;
	struct page *pages;
	unsigned long *bitmap;

	ir_table = iommu->ir_table = kzalloc(sizeof(struct ir_table),
					     GFP_ATOMIC);

	if (!iommu->ir_table)
		return -ENOMEM;

	pages = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
				 INTR_REMAP_PAGE_ORDER);

	if (!pages) {
		pr_err("IR%d: failed to allocate pages of order %d\n",
		       iommu->seq_id, INTR_REMAP_PAGE_ORDER);
		kfree(iommu->ir_table);
		return -ENOMEM;
	}

	bitmap = kcalloc(BITS_TO_LONGS(INTR_REMAP_TABLE_ENTRIES),
			 sizeof(long), GFP_ATOMIC);
	if (bitmap == NULL) {
		pr_err("IR%d: failed to allocate bitmap\n", iommu->seq_id);
		__free_pages(pages, INTR_REMAP_PAGE_ORDER);
		kfree(ir_table);
		return -ENOMEM;
	}

	ir_table->base = page_address(pages);
	ir_table->bitmap = bitmap;

	iommu_set_irq_remapping(iommu, mode);
	return 0;
}

static int hclge_set_vf_mc_mta_status(struct hclge_vport *vport,
				      u8 *msg, u8 idx, bool is_end)
{
#define HCLGE_MTA_STATUS_MSG_SIZE 13
#define HCLGE_MTA_STATUS_MSG_BITS \
				(HCLGE_MTA_STATUS_MSG_SIZE * BITS_PER_BYTE)
#define HCLGE_MTA_STATUS_MSG_END_BITS \
				(HCLGE_MTA_TBL_SIZE % HCLGE_MTA_STATUS_MSG_BITS)
	unsigned long status[BITS_TO_LONGS(HCLGE_MTA_STATUS_MSG_BITS)];
	u16 tbl_cnt;
	u16 tbl_idx;
	u8 msg_ofs;
	u8 msg_bit;

	tbl_cnt = is_end ? HCLGE_MTA_STATUS_MSG_END_BITS :
			HCLGE_MTA_STATUS_MSG_BITS;

	/* set msg field */
	msg_ofs = 0;
	msg_bit = 0;
	memset(status, 0, sizeof(status));
	for (tbl_idx = 0; tbl_idx < tbl_cnt; tbl_idx++) {
		if (msg[msg_ofs] & BIT(msg_bit))
			set_bit(tbl_idx, status);

		msg_bit++;
		if (msg_bit == BITS_PER_BYTE) {
			msg_bit = 0;
			msg_ofs++;
		}
	}

	return hclge_update_mta_status_common(vport,
					status, idx * HCLGE_MTA_STATUS_MSG_BITS,
					tbl_cnt, is_end);
}

static struct mlxsw_sp2_kvdl_part *
mlxsw_sp2_kvdl_part_init(struct mlxsw_sp *mlxsw_sp,
			 const struct mlxsw_sp2_kvdl_part_info *info)
{
	unsigned int indexes_per_usage_bit;
	struct mlxsw_sp2_kvdl_part *part;
	unsigned int index_range;
	unsigned int usage_bit_count;
	size_t usage_size;

	if (!mlxsw_core_res_valid(mlxsw_sp->core,
				  info->usage_bit_count_res_id) ||
	    !mlxsw_core_res_valid(mlxsw_sp->core,
				  info->index_range_res_id))
		return ERR_PTR(-EIO);
	usage_bit_count = mlxsw_core_res_get(mlxsw_sp->core,
					     info->usage_bit_count_res_id);
	index_range = mlxsw_core_res_get(mlxsw_sp->core,
					 info->index_range_res_id);

	/* For some partitions, one usage bit represents a group of indexes.
	 * That's why we compute the number of indexes per usage bit here,
	 * according to queried resources.
	 */
	indexes_per_usage_bit = index_range / usage_bit_count;

	usage_size = BITS_TO_LONGS(usage_bit_count) * sizeof(unsigned long);
	part = kzalloc(sizeof(*part) + usage_size, GFP_KERNEL);
	if (!part)
		return ERR_PTR(-ENOMEM);
	part->info = info;
	part->usage_bit_count = usage_bit_count;
	part->indexes_per_usage_bit = indexes_per_usage_bit;
	part->last_allocated_bit = usage_bit_count - 1;
	return part;
}

int mlx5_mpfs_init(struct mlx5_core_dev *dev)
{
	int l2table_size = 1 << MLX5_CAP_GEN(dev, log_max_l2_table);
	struct mlx5_mpfs *mpfs;

	if (!MLX5_VPORT_MANAGER(dev))
		return 0;

	mpfs = kzalloc(sizeof(*mpfs), GFP_KERNEL);
	if (!mpfs)
		return -ENOMEM;

	mutex_init(&mpfs->lock);
	mpfs->size   = l2table_size;
	mpfs->bitmap = kcalloc(BITS_TO_LONGS(l2table_size),
			       sizeof(uintptr_t), GFP_KERNEL);
	if (!mpfs->bitmap) {
		kfree(mpfs);
		return -ENOMEM;
	}

	dev->priv.mpfs = mpfs;
	return 0;
}

int hns_roce_bitmap_init(struct hns_roce_bitmap *bitmap, u32 num, u32 mask,
			 u32 reserved_bot, u32 reserved_top)
{
	u32 i;

	if (num != roundup_pow_of_two(num))
		return -EINVAL;

	bitmap->last = 0;
	bitmap->top = 0;
	bitmap->max = num - reserved_top;
	bitmap->mask = mask;
	bitmap->reserved_top = reserved_top;
	spin_lock_init(&bitmap->lock);
	bitmap->table = kcalloc(BITS_TO_LONGS(bitmap->max), sizeof(long),
				GFP_KERNEL);
	if (!bitmap->table)
		return -ENOMEM;

	for (i = 0; i < reserved_bot; ++i)
		set_bit(i, bitmap->table);

	return 0;
}

/**
 * iio_scan_mask_set() - set particular bit in the scan mask
 * @buffer: the buffer whose scan mask we are interested in
 * @bit: the bit to be set.
 **/
int iio_scan_mask_set(struct iio_buffer *buffer, int bit)
{
	struct iio_dev *indio_dev = buffer->indio_dev;
	unsigned long *mask;
	unsigned long *trialmask;

	trialmask = kmalloc(sizeof(*trialmask)*
			    BITS_TO_LONGS(indio_dev->masklength),
			    GFP_KERNEL);

	if (trialmask == NULL)
		return -ENOMEM;
	if (!indio_dev->masklength) {
		WARN_ON("trying to set scanmask prior to registering buffer\n");
		kfree(trialmask);
		return -EINVAL;
	}
	bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);
	set_bit(bit, trialmask);

	if (indio_dev->available_scan_masks) {
		mask = iio_scan_mask_match(indio_dev->available_scan_masks,
					   indio_dev->masklength,
					   trialmask);
		if (!mask) {
			kfree(trialmask);
			return -EINVAL;
		}
	}
	bitmap_copy(buffer->scan_mask, trialmask, indio_dev->masklength);
	buffer->scan_count++;

	kfree(trialmask);

	return 0;
};

int msi_bitmap_alloc(struct msi_bitmap *bmp, unsigned int irq_count,
                     struct device_node *of_node)
{
    int size;

    if (!irq_count)
        return -EINVAL;

    size = BITS_TO_LONGS(irq_count) * sizeof(long);
    pr_debug("msi_bitmap: allocator bitmap size is 0x%x bytes\n", size);

    bmp->bitmap = zalloc_maybe_bootmem(size, GFP_KERNEL);
    if (!bmp->bitmap) {
        pr_debug("msi_bitmap: ENOMEM allocating allocator bitmap!\n");
        return -ENOMEM;
    }

    /* We zalloc'ed the bitmap, so all irqs are free by default */
    spin_lock_init(&bmp->lock);
    bmp->of_node = of_node_get(of_node);
    bmp->irq_count = irq_count;

    return 0;
}

void
i915_gem_object_save_bit_17_swizzle(struct drm_i915_gem_object *obj)
{
	int page_count = obj->base.size >> PAGE_SHIFT;
	int i;

	if (obj->bit_17 == NULL) {
		obj->bit_17 = kmalloc(BITS_TO_LONGS(page_count) *
		    sizeof(long), DRM_I915_GEM, M_WAITOK);
		if (obj->bit_17 == NULL) {
			DRM_ERROR("Failed to allocate memory for bit 17 "
				  "record\n");
			return;
		}
	}

	/* XXXKIB: review locking, atomics might be not needed there */
	for (i = 0; i < page_count; i++) {
		if (VM_PAGE_TO_PHYS(obj->pages[i]) & (1 << 17))
			set_bit(i, obj->bit_17);
		else
			clear_bit(i, obj->bit_17);
	}
}

 * EV_ABS events which should not be cached are listed here.
 */
static unsigned int input_abs_bypass_init_data[] __initdata = {
	ABS_MT_TOUCH_MAJOR,
	ABS_MT_TOUCH_MINOR,
	ABS_MT_WIDTH_MAJOR,
	ABS_MT_WIDTH_MINOR,
	ABS_MT_ORIENTATION,
	ABS_MT_POSITION_X,
	ABS_MT_POSITION_Y,
	ABS_MT_TOOL_TYPE,
	ABS_MT_BLOB_ID,
	ABS_MT_PRESSURE,	
	0
};
static unsigned long input_abs_bypass[BITS_TO_LONGS(ABS_CNT)];

static LIST_HEAD(input_dev_list);
static LIST_HEAD(input_handler_list);

/*
 * input_mutex protects access to both input_dev_list and input_handler_list.
 * This also causes input_[un]register_device and input_[un]register_handler
 * be mutually exclusive which simplifies locking in drivers implementing
 * input handlers.
 */
static DEFINE_MUTEX(input_mutex);

static struct input_handler *input_table[8];

static inline int is_event_supported(unsigned int code,