> +/*
> + * As shared memory is supported in CXL3.0 spec, we can transfer data via CXL shared memory.
> + * CBD means CXL block device, it use CXL shared memory to transport command and data to
> + * access block device in different host, as shown below:
> + *
> + * ┌───────────────────────────────┐ ┌────────────────────────────────────┐
> + * │ node-1 │ │ node-2 │
> + * ├───────────────────────────────┤ ├────────────────────────────────────┤
> + * │ │ │ │
> + * │ ┌───────┤ ├─────────┐ │
> + * │ │ cbd0 │ │ backend0├──────────────────┐ │
> + * │ ├───────┤ ├─────────┤ │ │
> + * │ │ pmem0 │ │ pmem0 │ ▼ │
> + * │ ┌───────┴───────┤ ├─────────┴────┐ ┌───────────────┤
> + * │ │ cxl driver │ │ cxl driver │ │ /dev/sda │
> + * └───────────────┴────────┬──────┘ └─────┬────────┴─────┴───────────────┘
> + * │ │
> + * │ │
> + * │ CXL CXL │
> + * └────────────────┐ ┌───────────┘
> + * │ │
> + * │ │
> + * │ │
> + * ┌───┴───────────────┴─────┐
> + * │ shared memory device │
> + * └─────────────────────────┘
> + *
> + * any read/write to cbd0 on node-1 will be transferred to node-2 /dev/sda. It works similar with
> + * nbd (network block device), but it transfer data via CXL shared memory rather than network.
> + */
> +
> +/* printk */
I don't think you need above comment ..
> +#define cbd_err(fmt, ...) \
> + pr_err("cbd: %s:%u " fmt, __func__, __LINE__, ##__VA_ARGS__)
you can use #define pr_fmt and remove cmd: prefixes in each pr_xxx above ?
> +#define cbd_info(fmt, ...) \
> + pr_info("cbd: %s:%u " fmt, __func__, __LINE__, ##__VA_ARGS__)
> +#define cbd_debug(fmt, ...) \
> + pr_debug("cbd: %s:%u " fmt, __func__, __LINE__, ##__VA_ARGS__)
> +
> +#define cbdt_err(transport, fmt, ...) \
> + cbd_err("cbd_transport%u: " fmt, \
> + transport->id, ##__VA_ARGS__)
> +#define cbdt_info(transport, fmt, ...) \
> + cbd_info("cbd_transport%u: " fmt, \
> + transport->id, ##__VA_ARGS__)
> +#define cbdt_debug(transport, fmt, ...) \
> + cbd_debug("cbd_transport%u: " fmt, \
> + transport->id, ##__VA_ARGS__)
> +
> +#define cbd_backend_err(backend, fmt, ...) \
> + cbdt_err(backend->cbdt, "backend%d: " fmt, \
> + backend->backend_id, ##__VA_ARGS__)
> +#define cbd_backend_info(backend, fmt, ...) \
> + cbdt_info(backend->cbdt, "backend%d: " fmt, \
> + backend->backend_id, ##__VA_ARGS__)
> +#define cbd_backend_debug(backend, fmt, ...) \
> + cbdt_debug(backend->cbdt, "backend%d: " fmt, \
> + backend->backend_id, ##__VA_ARGS__)
> +
> +#define cbd_handler_err(handler, fmt, ...) \
> + cbd_backend_err(handler->cbdb, "handler%d: " fmt, \
> + handler->channel.channel_id, ##__VA_ARGS__)
> +#define cbd_handler_info(handler, fmt, ...) \
> + cbd_backend_info(handler->cbdb, "handler%d: " fmt, \
> + handler->channel.channel_id, ##__VA_ARGS__)
> +#define cbd_handler_debug(handler, fmt, ...) \
> + cbd_backend_debug(handler->cbdb, "handler%d: " fmt, \
> + handler->channel.channel_id, ##__VA_ARGS__)
> +
> +#define cbd_blk_err(dev, fmt, ...) \
> + cbdt_err(dev->cbdt, "cbd%d: " fmt, \
> + dev->mapped_id, ##__VA_ARGS__)
> +#define cbd_blk_info(dev, fmt, ...) \
> + cbdt_info(dev->cbdt, "cbd%d: " fmt, \
> + dev->mapped_id, ##__VA_ARGS__)
> +#define cbd_blk_debug(dev, fmt, ...) \
> + cbdt_debug(dev->cbdt, "cbd%d: " fmt, \
> + dev->mapped_id, ##__VA_ARGS__)
> +
> +#define cbd_queue_err(queue, fmt, ...) \
> + cbd_blk_err(queue->cbd_blkdev, "queue-%d: " fmt, \
> + queue->index, ##__VA_ARGS__)
> +#define cbd_queue_info(queue, fmt, ...) \
> + cbd_blk_info(queue->cbd_blkdev, "queue-%d: " fmt, \
> + queue->index, ##__VA_ARGS__)
> +#define cbd_queue_debug(queue, fmt, ...) \
> + cbd_blk_debug(queue->cbd_blkdev, "queue-%d: " fmt, \
> + queue->index, ##__VA_ARGS__)
> +
> +#define cbd_channel_err(channel, fmt, ...) \
> + cbdt_err(channel->cbdt, "channel%d: " fmt, \
> + channel->channel_id, ##__VA_ARGS__)
> +#define cbd_channel_info(channel, fmt, ...) \
> + cbdt_info(channel->cbdt, "channel%d: " fmt, \
> + channel->channel_id, ##__VA_ARGS__)
> +#define cbd_channel_debug(channel, fmt, ...) \
> + cbdt_debug(channel->cbdt, "channel%d: " fmt, \
> + channel->channel_id, ##__VA_ARGS__)
> +
[...]
> +
> +struct cbd_se {
> + struct cbd_se_hdr header;
> + u64 priv_data; // pointer to cbd_request
use /**/ instead //
-ck
