[lttng-modules.git] / src / lttng-ring-buffer-metadata-client.h

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * lttng-ring-buffer-client.h
 *
 * LTTng lib ring buffer client template.
 *
 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

#include <linux/module.h>
#include <linux/types.h>
#include <wrapper/vmalloc.h>	/* for wrapper_vmalloc_sync_mappings() */
#include <lttng/events.h>
#include <lttng/events-internal.h>
#include <lttng/tracer.h>

static struct lttng_transport lttng_relay_transport;

struct metadata_packet_header {
	uint32_t magic;			/* 0x75D11D57 */
	uint8_t  uuid[16];		/* Unique Universal Identifier */
	uint32_t checksum;		/* 0 if unused */
	uint32_t content_size;		/* in bits */
	uint32_t packet_size;		/* in bits */
	uint8_t  compression_scheme;	/* 0 if unused */
	uint8_t  encryption_scheme;	/* 0 if unused */
	uint8_t  checksum_scheme;	/* 0 if unused */
	uint8_t  major;			/* CTF spec major version number */
	uint8_t  minor;			/* CTF spec minor version number */
	uint8_t  header_end[0];
};

struct metadata_record_header {
	uint8_t header_end[0];		/* End of header */
};

static const struct lttng_kernel_ring_buffer_config client_config;

static inline
u64 lib_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
{
	return 0;
}

static inline
size_t record_header_size(const struct lttng_kernel_ring_buffer_config *config,
				 struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lttng_kernel_ring_buffer_ctx *ctx,
				 void *client_ctx)
{
	return 0;
}

#include <ringbuffer/api.h>

static u64 client_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
{
	return 0;
}

static
size_t client_record_header_size(const struct lttng_kernel_ring_buffer_config *config,
				 struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lttng_kernel_ring_buffer_ctx *ctx,
				 void *client_ctx)
{
	return 0;
}

/**
 * client_packet_header_size - called on buffer-switch to a new sub-buffer
 *
 * Return header size without padding after the structure. Don't use packed
 * structure because gcc generates inefficient code on some architectures
 * (powerpc, mips..)
 */
static size_t client_packet_header_size(void)
{
	return offsetof(struct metadata_packet_header, header_end);
}

static void client_buffer_begin(struct lttng_kernel_ring_buffer *buf, u64 tsc,
				unsigned int subbuf_idx)
{
	struct lttng_kernel_ring_buffer_channel *chan = buf->backend.chan;
	struct metadata_packet_header *header =
		(struct metadata_packet_header *)
			lib_ring_buffer_offset_address(&buf->backend,
				subbuf_idx * chan->backend.subbuf_size);
	struct lttng_metadata_cache *metadata_cache =
		channel_get_private(chan);

	header->magic = TSDL_MAGIC_NUMBER;
	memcpy(header->uuid, metadata_cache->uuid.b,
		sizeof(metadata_cache->uuid));
	header->checksum = 0;		/* 0 if unused */
	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	header->packet_size = 0xFFFFFFFF;  /* in bits, for debugging */
	header->compression_scheme = 0;	/* 0 if unused */
	header->encryption_scheme = 0;	/* 0 if unused */
	header->checksum_scheme = 0;	/* 0 if unused */
	header->major = CTF_SPEC_MAJOR;
	header->minor = CTF_SPEC_MINOR;
}

/*
 * offset is assumed to never be 0 here : never deliver a completely empty
 * subbuffer. data_size is between 1 and subbuf_size.
 */
static void client_buffer_end(struct lttng_kernel_ring_buffer *buf, u64 tsc,
			      unsigned int subbuf_idx, unsigned long data_size)
{
	struct lttng_kernel_ring_buffer_channel *chan = buf->backend.chan;
	struct metadata_packet_header *header =
		(struct metadata_packet_header *)
			lib_ring_buffer_offset_address(&buf->backend,
				subbuf_idx * chan->backend.subbuf_size);
	unsigned long records_lost = 0;

	header->content_size = data_size * CHAR_BIT;		/* in bits */
	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
	/*
	 * We do not care about the records lost count, because the metadata
	 * channel waits and retry.
	 */
	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	WARN_ON_ONCE(records_lost != 0);
}

static int client_buffer_create(struct lttng_kernel_ring_buffer *buf, void *priv,
				int cpu, const char *name)
{
	return 0;
}

static void client_buffer_finalize(struct lttng_kernel_ring_buffer *buf, void *priv, int cpu)
{
}

static int client_timestamp_begin(const struct lttng_kernel_ring_buffer_config *config,
		struct lttng_kernel_ring_buffer *buf, uint64_t *timestamp_begin)
{
	return -ENOSYS;
}

static int client_timestamp_end(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *timestamp_end)
{
	return -ENOSYS;
}

static int client_events_discarded(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *events_discarded)
{
	return -ENOSYS;
}

static int client_current_timestamp(const struct lttng_kernel_ring_buffer_config *config,
		struct lttng_kernel_ring_buffer *bufb,
		uint64_t *ts)
{
	return -ENOSYS;
}

static int client_content_size(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *content_size)
{
	return -ENOSYS;
}

static int client_packet_size(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *packet_size)
{
	return -ENOSYS;
}

static int client_stream_id(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *stream_id)
{
	return -ENOSYS;
}

static int client_sequence_number(const struct lttng_kernel_ring_buffer_config *config,
			struct lttng_kernel_ring_buffer *bufb,
			uint64_t *seq)
{
	return -ENOSYS;
}

static
int client_instance_id(const struct lttng_kernel_ring_buffer_config *config,
		struct lttng_kernel_ring_buffer *bufb,
		uint64_t *id)
{
	return -ENOSYS;
}

static const struct lttng_kernel_ring_buffer_config client_config = {
	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	.cb.record_header_size = client_record_header_size,
	.cb.subbuffer_header_size = client_packet_header_size,
	.cb.buffer_begin = client_buffer_begin,
	.cb.buffer_end = client_buffer_end,
	.cb.buffer_create = client_buffer_create,
	.cb.buffer_finalize = client_buffer_finalize,

	.tsc_bits = 0,
	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	.sync = RING_BUFFER_SYNC_GLOBAL,
	.mode = RING_BUFFER_MODE_TEMPLATE,
	.backend = RING_BUFFER_PAGE,
	.output = RING_BUFFER_OUTPUT_TEMPLATE,
	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	.ipi = RING_BUFFER_IPI_BARRIER,
	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
};

static
void release_priv_ops(void *priv_ops)
{
	module_put(THIS_MODULE);
}

static
void lttng_channel_destroy(struct lttng_kernel_ring_buffer_channel *chan)
{
	channel_destroy(chan);
}

static
struct lttng_kernel_ring_buffer_channel *_channel_create(const char *name,
				void *priv, void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval)
{
	struct lttng_kernel_channel_buffer *lttng_chan = priv;
	struct lttng_kernel_ring_buffer_channel *chan;

	chan = channel_create(&client_config, name,
			      lttng_chan->parent.session->priv->metadata_cache, buf_addr,
			      subbuf_size, num_subbuf, switch_timer_interval,
			      read_timer_interval);
	if (chan) {
		/*
		 * Ensure this module is not unloaded before we finish
		 * using lttng_relay_transport.ops.
		 */
		if (!try_module_get(THIS_MODULE)) {
			printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
			goto error;
		}
		chan->backend.priv_ops = &lttng_relay_transport.ops;
		chan->backend.release_priv_ops = release_priv_ops;
	}
	return chan;

error:
	lttng_channel_destroy(chan);
	return NULL;
}

static
struct lttng_kernel_ring_buffer *lttng_buffer_read_open(struct lttng_kernel_ring_buffer_channel *chan)
{
	struct lttng_kernel_ring_buffer *buf;

	buf = channel_get_ring_buffer(&client_config, chan, 0);
	if (!lib_ring_buffer_open_read(buf))
		return buf;
	return NULL;
}

static
int lttng_buffer_has_read_closed_stream(struct lttng_kernel_ring_buffer_channel *chan)
{
	struct lttng_kernel_ring_buffer *buf;
	int cpu;

	for_each_channel_cpu(cpu, chan) {
		buf = channel_get_ring_buffer(&client_config, chan, cpu);
		if (!atomic_long_read(&buf->active_readers))
			return 1;
	}
	return 0;
}

static
void lttng_buffer_read_close(struct lttng_kernel_ring_buffer *buf)
{
	lib_ring_buffer_release_read(buf);
}

static
int lttng_event_reserve(struct lttng_kernel_ring_buffer_ctx *ctx)
{
	struct lttng_kernel_ring_buffer_channel *chan = ctx->client_priv;
	int ret;

	memset(&ctx->priv, 0, sizeof(ctx->priv));
	ctx->priv.chan = chan;

	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
	if (ret)
		return ret;
	lib_ring_buffer_backend_get_pages(&client_config, ctx,
			&ctx->priv.backend_pages);
	return 0;

}

static
void lttng_event_commit(struct lttng_kernel_ring_buffer_ctx *ctx)
{
	lib_ring_buffer_commit(&client_config, ctx);
}

static
void lttng_event_write(struct lttng_kernel_ring_buffer_ctx *ctx, const void *src,
		     size_t len, size_t alignment)
{
	lib_ring_buffer_align_ctx(ctx, alignment);
	lib_ring_buffer_write(&client_config, ctx, src, len);
}

static
void lttng_event_write_from_user(struct lttng_kernel_ring_buffer_ctx *ctx,
			       const void __user *src, size_t len, size_t alignment)
{
	lib_ring_buffer_align_ctx(ctx, alignment);
	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
}

static
void lttng_event_memset(struct lttng_kernel_ring_buffer_ctx *ctx,
		int c, size_t len)
{
	lib_ring_buffer_memset(&client_config, ctx, c, len);
}

static
void lttng_event_strcpy(struct lttng_kernel_ring_buffer_ctx *ctx, const char *src,
		size_t len)
{
	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
}

static
size_t lttng_packet_avail_size(struct lttng_kernel_ring_buffer_channel *chan)
{
	unsigned long o_begin;
	struct lttng_kernel_ring_buffer *buf;

	buf = chan->backend.buf;	/* Only for global buffer ! */
	o_begin = v_read(&client_config, &buf->offset);
	if (subbuf_offset(o_begin, chan) != 0) {
		return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	} else {
		return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
			- sizeof(struct metadata_packet_header);
	}
}

static
wait_queue_head_t *lttng_get_writer_buf_wait_queue(struct lttng_kernel_ring_buffer_channel *chan, int cpu)
{
	struct lttng_kernel_ring_buffer *buf = channel_get_ring_buffer(&client_config,
					chan, cpu);
	return &buf->write_wait;
}

static
wait_queue_head_t *lttng_get_hp_wait_queue(struct lttng_kernel_ring_buffer_channel *chan)
{
	return &chan->hp_wait;
}

static
int lttng_is_finalized(struct lttng_kernel_ring_buffer_channel *chan)
{
	return lib_ring_buffer_channel_is_finalized(chan);
}

static
int lttng_is_disabled(struct lttng_kernel_ring_buffer_channel *chan)
{
	return lib_ring_buffer_channel_is_disabled(chan);
}

static struct lttng_transport lttng_relay_transport = {
	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	.owner = THIS_MODULE,
	.ops = {
		.priv = __LTTNG_COMPOUND_LITERAL(struct lttng_kernel_channel_buffer_ops_private, {
			.pub = &lttng_relay_transport.ops,
			.channel_create = _channel_create,
			.channel_destroy = lttng_channel_destroy,
			.buffer_read_open = lttng_buffer_read_open,
			.buffer_has_read_closed_stream =
				lttng_buffer_has_read_closed_stream,
			.buffer_read_close = lttng_buffer_read_close,
			.packet_avail_size = lttng_packet_avail_size,
			.get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue,
			.get_hp_wait_queue = lttng_get_hp_wait_queue,
			.is_finalized = lttng_is_finalized,
			.is_disabled = lttng_is_disabled,
			.timestamp_begin = client_timestamp_begin,
			.timestamp_end = client_timestamp_end,
			.events_discarded = client_events_discarded,
			.content_size = client_content_size,
			.packet_size = client_packet_size,
			.stream_id = client_stream_id,
			.current_timestamp = client_current_timestamp,
			.sequence_number = client_sequence_number,
			.instance_id = client_instance_id,
		}),
		.event_reserve = lttng_event_reserve,
		.event_commit = lttng_event_commit,
		.event_write_from_user = lttng_event_write_from_user,
		.event_memset = lttng_event_memset,
		.event_write = lttng_event_write,
		.event_strcpy = lttng_event_strcpy,
	},
};

static int __init lttng_ring_buffer_client_init(void)
{
	/*
	 * This vmalloc sync all also takes care of the lib ring buffer
	 * vmalloc'd module pages when it is built as a module into LTTng.
	 */
	wrapper_vmalloc_sync_mappings();
	lttng_transport_register(&lttng_relay_transport);
	return 0;
}

module_init(lttng_ring_buffer_client_init);

static void __exit lttng_ring_buffer_client_exit(void)
{
	lttng_transport_unregister(&lttng_relay_transport);
}

module_exit(lttng_ring_buffer_client_exit);

MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
		   " client");
MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
	LTTNG_MODULES_EXTRAVERSION);
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed	2	*
a90917c3	3	* lttng-ring-buffer-client.h
881833e3	4	*
881833e3 MD	5	* LTTng lib ring buffer client template.
881833e3 MD	6	*
886d51a3	7	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
881833e3 MD	8	*/
	9
	10	#include <linux/module.h>
	11	#include <linux/types.h>
263b6c88	12	#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
2df37e95	13	#include <lttng/events.h>
e8c0bbd3	14	#include <lttng/events-internal.h>
2df37e95	15	#include <lttng/tracer.h>
881833e3	16
dd5a0db3 MD	17	static struct lttng_transport lttng_relay_transport;
dd5a0db3 MD	18
881833e3 MD	19	struct metadata_packet_header {
881833e3 MD	20	uint32_t magic; /* 0x75D11D57 */
1ec3f75a	21	uint8_t uuid[16]; /* Unique Universal Identifier */
881833e3 MD	22	uint32_t checksum; /* 0 if unused */
	23	uint32_t content_size; /* in bits */
	24	uint32_t packet_size; /* in bits */
	25	uint8_t compression_scheme; /* 0 if unused */
	26	uint8_t encryption_scheme; /* 0 if unused */
	27	uint8_t checksum_scheme; /* 0 if unused */
4173df96 MD	28	uint8_t major; /* CTF spec major version number */
4173df96 MD	29	uint8_t minor; /* CTF spec minor version number */
881833e3 MD	30	uint8_t header_end[0];
	31	};
	32
	33	struct metadata_record_header {
	34	uint8_t header_end[0]; /* End of header */
	35	};
	36
e20c0fec	37	static const struct lttng_kernel_ring_buffer_config client_config;
881833e3 MD	38
881833e3 MD	39	static inline
860c213b	40	u64 lib_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
881833e3 MD	41	{
	42	return 0;
	43	}
	44
	45	static inline
e20c0fec	46	size_t record_header_size(const struct lttng_kernel_ring_buffer_config *config,
860c213b	47	struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
64c796d8	48	size_t *pre_header_padding,
8a57ec02	49	struct lttng_kernel_ring_buffer_ctx *ctx,
cc62f29e	50	void *client_ctx)
881833e3 MD	51	{
	52	return 0;
	53	}
	54
24591303	55	#include <ringbuffer/api.h>
881833e3	56
860c213b	57	static u64 client_ring_buffer_clock_read(struct lttng_kernel_ring_buffer_channel *chan)
881833e3 MD	58	{
	59	return 0;
	60	}
	61
	62	static
e20c0fec	63	size_t client_record_header_size(const struct lttng_kernel_ring_buffer_config *config,
860c213b	64	struct lttng_kernel_ring_buffer_channel *chan, size_t offset,
881833e3	65	size_t *pre_header_padding,
8a57ec02	66	struct lttng_kernel_ring_buffer_ctx *ctx,
cc62f29e	67	void *client_ctx)
881833e3 MD	68	{
	69	return 0;
	70	}
	71
	72	/**
	73	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	74	*
	75	* Return header size without padding after the structure. Don't use packed
	76	* structure because gcc generates inefficient code on some architectures
	77	* (powerpc, mips..)
	78	*/
	79	static size_t client_packet_header_size(void)
	80	{
	81	return offsetof(struct metadata_packet_header, header_end);
	82	}
	83
e20c0fec	84	static void client_buffer_begin(struct lttng_kernel_ring_buffer *buf, u64 tsc,
881833e3 MD	85	unsigned int subbuf_idx)
881833e3 MD	86	{
860c213b	87	struct lttng_kernel_ring_buffer_channel *chan = buf->backend.chan;
881833e3 MD	88	struct metadata_packet_header *header =
	89	(struct metadata_packet_header *)
	90	lib_ring_buffer_offset_address(&buf->backend,
	91	subbuf_idx * chan->backend.subbuf_size);
a36580d5 MD	92	struct lttng_metadata_cache *metadata_cache =
a36580d5 MD	93	channel_get_private(chan);
881833e3 MD	94
881833e3 MD	95	header->magic = TSDL_MAGIC_NUMBER;
a36580d5 MD	96	memcpy(header->uuid, metadata_cache->uuid.b,
a36580d5 MD	97	sizeof(metadata_cache->uuid));
881833e3 MD	98	header->checksum = 0; /* 0 if unused */
	99	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	100	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	101	header->compression_scheme = 0; /* 0 if unused */
	102	header->encryption_scheme = 0; /* 0 if unused */
	103	header->checksum_scheme = 0; /* 0 if unused */
4173df96 MD	104	header->major = CTF_SPEC_MAJOR;
4173df96 MD	105	header->minor = CTF_SPEC_MINOR;
881833e3 MD	106	}
	107
	108	/*
	109	* offset is assumed to never be 0 here : never deliver a completely empty
	110	* subbuffer. data_size is between 1 and subbuf_size.
	111	*/
e20c0fec	112	static void client_buffer_end(struct lttng_kernel_ring_buffer *buf, u64 tsc,
881833e3 MD	113	unsigned int subbuf_idx, unsigned long data_size)
881833e3 MD	114	{
860c213b	115	struct lttng_kernel_ring_buffer_channel *chan = buf->backend.chan;
d793d5e1	116	struct metadata_packet_header *header =
1ec3f75a	117	(struct metadata_packet_header *)
881833e3 MD	118	lib_ring_buffer_offset_address(&buf->backend,
	119	subbuf_idx * chan->backend.subbuf_size);
	120	unsigned long records_lost = 0;
	121
	122	header->content_size = data_size * CHAR_BIT; /* in bits */
	123	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
71c1d843 MD	124	/*
	125	* We do not care about the records lost count, because the metadata
	126	* channel waits and retry.
	127	*/
	128	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
881833e3 MD	129	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	130	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	131	WARN_ON_ONCE(records_lost != 0);
	132	}
	133
e20c0fec	134	static int client_buffer_create(struct lttng_kernel_ring_buffer buf, void priv,
881833e3 MD	135	int cpu, const char *name)
	136	{
	137	return 0;
	138	}
	139
e20c0fec	140	static void client_buffer_finalize(struct lttng_kernel_ring_buffer buf, void priv, int cpu)
881833e3 MD	141	{
	142	}
	143
e20c0fec MD	144	static int client_timestamp_begin(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	145	struct lttng_kernel_ring_buffer buf, uint64_t timestamp_begin)
3b731ab1 JD	146	{
	147	return -ENOSYS;
	148	}
	149
e20c0fec MD	150	static int client_timestamp_end(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	151	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	152	uint64_t *timestamp_end)
	153	{
	154	return -ENOSYS;
	155	}
	156
e20c0fec MD	157	static int client_events_discarded(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	158	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	159	uint64_t *events_discarded)
	160	{
	161	return -ENOSYS;
	162	}
	163
e20c0fec MD	164	static int client_current_timestamp(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	165	struct lttng_kernel_ring_buffer *bufb,
2348ca17 JD	166	uint64_t *ts)
	167	{
	168	return -ENOSYS;
	169	}
	170
e20c0fec MD	171	static int client_content_size(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	172	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	173	uint64_t *content_size)
	174	{
	175	return -ENOSYS;
	176	}
	177
e20c0fec MD	178	static int client_packet_size(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	179	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	180	uint64_t *packet_size)
	181	{
	182	return -ENOSYS;
	183	}
	184
e20c0fec MD	185	static int client_stream_id(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	186	struct lttng_kernel_ring_buffer *bufb,
3b731ab1 JD	187	uint64_t *stream_id)
	188	{
	189	return -ENOSYS;
	190	}
	191
e20c0fec MD	192	static int client_sequence_number(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	193	struct lttng_kernel_ring_buffer *bufb,
5b3cf4f9 JD	194	uint64_t *seq)
	195	{
	196	return -ENOSYS;
	197	}
	198
5594698f	199	static
e20c0fec MD	200	int client_instance_id(const struct lttng_kernel_ring_buffer_config *config,
e20c0fec MD	201	struct lttng_kernel_ring_buffer *bufb,
5594698f JD	202	uint64_t *id)
	203	{
	204	return -ENOSYS;
	205	}
	206
e20c0fec	207	static const struct lttng_kernel_ring_buffer_config client_config = {
881833e3 MD	208	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	209	.cb.record_header_size = client_record_header_size,
	210	.cb.subbuffer_header_size = client_packet_header_size,
	211	.cb.buffer_begin = client_buffer_begin,
	212	.cb.buffer_end = client_buffer_end,
	213	.cb.buffer_create = client_buffer_create,
	214	.cb.buffer_finalize = client_buffer_finalize,
	215
	216	.tsc_bits = 0,
	217	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	218	.sync = RING_BUFFER_SYNC_GLOBAL,
	219	.mode = RING_BUFFER_MODE_TEMPLATE,
	220	.backend = RING_BUFFER_PAGE,
2db1399a	221	.output = RING_BUFFER_OUTPUT_TEMPLATE,
881833e3 MD	222	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	223	.ipi = RING_BUFFER_IPI_BARRIER,
	224	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
	225	};
	226
dd5a0db3 MD	227	static
	228	void release_priv_ops(void *priv_ops)
	229	{
	230	module_put(THIS_MODULE);
	231	}
	232
	233	static
860c213b	234	void lttng_channel_destroy(struct lttng_kernel_ring_buffer_channel *chan)
dd5a0db3 MD	235	{
	236	channel_destroy(chan);
	237	}
	238
881833e3	239	static
860c213b	240	struct lttng_kernel_ring_buffer_channel _channel_create(const char name,
5cf4b87c	241	void priv, void buf_addr,
881833e3 MD	242	size_t subbuf_size, size_t num_subbuf,
	243	unsigned int switch_timer_interval,
	244	unsigned int read_timer_interval)
	245	{
f7d06400	246	struct lttng_kernel_channel_buffer *lttng_chan = priv;
860c213b	247	struct lttng_kernel_ring_buffer_channel *chan;
dd5a0db3	248
a36580d5	249	chan = channel_create(&client_config, name,
f7d06400	250	lttng_chan->parent.session->priv->metadata_cache, buf_addr,
881833e3 MD	251	subbuf_size, num_subbuf, switch_timer_interval,
881833e3 MD	252	read_timer_interval);
dd5a0db3 MD	253	if (chan) {
	254	/*
	255	* Ensure this module is not unloaded before we finish
	256	* using lttng_relay_transport.ops.
	257	*/
	258	if (!try_module_get(THIS_MODULE)) {
5a15f70c	259	printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
dd5a0db3 MD	260	goto error;
	261	}
	262	chan->backend.priv_ops = &lttng_relay_transport.ops;
	263	chan->backend.release_priv_ops = release_priv_ops;
	264	}
	265	return chan;
881833e3	266
dd5a0db3 MD	267	error:
	268	lttng_channel_destroy(chan);
	269	return NULL;
881833e3 MD	270	}
	271
	272	static
e20c0fec	273	struct lttng_kernel_ring_buffer lttng_buffer_read_open(struct lttng_kernel_ring_buffer_channel chan)
881833e3	274	{
e20c0fec	275	struct lttng_kernel_ring_buffer *buf;
881833e3	276
cd4bd11f MD	277	buf = channel_get_ring_buffer(&client_config, chan, 0);
	278	if (!lib_ring_buffer_open_read(buf))
	279	return buf;
881833e3 MD	280	return NULL;
	281	}
	282
f71ecafa	283	static
860c213b	284	int lttng_buffer_has_read_closed_stream(struct lttng_kernel_ring_buffer_channel *chan)
f71ecafa	285	{
e20c0fec	286	struct lttng_kernel_ring_buffer *buf;
f71ecafa MD	287	int cpu;
	288
	289	for_each_channel_cpu(cpu, chan) {
	290	buf = channel_get_ring_buffer(&client_config, chan, cpu);
	291	if (!atomic_long_read(&buf->active_readers))
	292	return 1;
	293	}
	294	return 0;
	295	}
	296
881833e3	297	static
e20c0fec	298	void lttng_buffer_read_close(struct lttng_kernel_ring_buffer *buf)
881833e3 MD	299	{
881833e3 MD	300	lib_ring_buffer_release_read(buf);
881833e3 MD	301	}
881833e3 MD	302
c099397a	303	static
8a57ec02	304	int lttng_event_reserve(struct lttng_kernel_ring_buffer_ctx *ctx)
881833e3	305	{
860c213b	306	struct lttng_kernel_ring_buffer_channel *chan = ctx->client_priv;
85a07c33 MD	307	int ret;
85a07c33 MD	308
b1199bd3 MD	309	memset(&ctx->priv, 0, sizeof(ctx->priv));
	310	ctx->priv.chan = chan;
	311
cc62f29e	312	ret = lib_ring_buffer_reserve(&client_config, ctx, NULL);
85a07c33 MD	313	if (ret)
	314	return ret;
	315	lib_ring_buffer_backend_get_pages(&client_config, ctx,
b1199bd3	316	&ctx->priv.backend_pages);
85a07c33 MD	317	return 0;
85a07c33 MD	318
881833e3 MD	319	}
881833e3 MD	320
c099397a	321	static
8a57ec02	322	void lttng_event_commit(struct lttng_kernel_ring_buffer_ctx *ctx)
881833e3 MD	323	{
	324	lib_ring_buffer_commit(&client_config, ctx);
	325	}
	326
c099397a	327	static
8a57ec02	328	void lttng_event_write(struct lttng_kernel_ring_buffer_ctx ctx, const void src,
f5ffbd77	329	size_t len, size_t alignment)
881833e3	330	{
f5ffbd77	331	lib_ring_buffer_align_ctx(ctx, alignment);
881833e3 MD	332	lib_ring_buffer_write(&client_config, ctx, src, len);
	333	}
	334
4ea00e4f	335	static
8a57ec02	336	void lttng_event_write_from_user(struct lttng_kernel_ring_buffer_ctx *ctx,
f5ffbd77	337	const void __user *src, size_t len, size_t alignment)
4ea00e4f	338	{
f5ffbd77	339	lib_ring_buffer_align_ctx(ctx, alignment);
7b8ea3a5	340	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
4ea00e4f JD	341	}
4ea00e4f JD	342
58aa5d24	343	static
8a57ec02	344	void lttng_event_memset(struct lttng_kernel_ring_buffer_ctx *ctx,
58aa5d24 MD	345	int c, size_t len)
	346	{
	347	lib_ring_buffer_memset(&client_config, ctx, c, len);
	348	}
	349
16f78f3a	350	static
8a57ec02	351	void lttng_event_strcpy(struct lttng_kernel_ring_buffer_ctx ctx, const char src,
16f78f3a MD	352	size_t len)
	353	{
	354	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
	355	}
	356
1ec3f75a	357	static
860c213b	358	size_t lttng_packet_avail_size(struct lttng_kernel_ring_buffer_channel *chan)
1ec3f75a MD	359	{
1ec3f75a MD	360	unsigned long o_begin;
e20c0fec	361	struct lttng_kernel_ring_buffer *buf;
1ec3f75a MD	362
	363	buf = chan->backend.buf; /* Only for global buffer ! */
	364	o_begin = v_read(&client_config, &buf->offset);
	365	if (subbuf_offset(o_begin, chan) != 0) {
	366	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	367	} else {
	368	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	369	- sizeof(struct metadata_packet_header);
	370	}
	371	}
	372
c099397a	373	static
860c213b	374	wait_queue_head_t lttng_get_writer_buf_wait_queue(struct lttng_kernel_ring_buffer_channel chan, int cpu)
c099397a	375	{
e20c0fec	376	struct lttng_kernel_ring_buffer *buf = channel_get_ring_buffer(&client_config,
71c1d843 MD	377	chan, cpu);
71c1d843 MD	378	return &buf->write_wait;
24cedcfe MD	379	}
	380
	381	static
860c213b	382	wait_queue_head_t lttng_get_hp_wait_queue(struct lttng_kernel_ring_buffer_channel chan)
24cedcfe MD	383	{
	384	return &chan->hp_wait;
	385	}
	386
	387	static
860c213b	388	int lttng_is_finalized(struct lttng_kernel_ring_buffer_channel *chan)
24cedcfe MD	389	{
24cedcfe MD	390	return lib_ring_buffer_channel_is_finalized(chan);
c099397a MD	391	}
c099397a MD	392
254ec7bc	393	static
860c213b	394	int lttng_is_disabled(struct lttng_kernel_ring_buffer_channel *chan)
254ec7bc MD	395	{
	396	return lib_ring_buffer_channel_is_disabled(chan);
	397	}
	398
a90917c3	399	static struct lttng_transport lttng_relay_transport = {
881833e3 MD	400	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	401	.owner = THIS_MODULE,
	402	.ops = {
4a399b76 MD	403	.priv = __LTTNG_COMPOUND_LITERAL(struct lttng_kernel_channel_buffer_ops_private, {
	404	.pub = &lttng_relay_transport.ops,
	405	.channel_create = _channel_create,
	406	.channel_destroy = lttng_channel_destroy,
	407	.buffer_read_open = lttng_buffer_read_open,
	408	.buffer_has_read_closed_stream =
	409	lttng_buffer_has_read_closed_stream,
	410	.buffer_read_close = lttng_buffer_read_close,
	411	.packet_avail_size = lttng_packet_avail_size,
	412	.get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue,
	413	.get_hp_wait_queue = lttng_get_hp_wait_queue,
	414	.is_finalized = lttng_is_finalized,
	415	.is_disabled = lttng_is_disabled,
	416	.timestamp_begin = client_timestamp_begin,
	417	.timestamp_end = client_timestamp_end,
	418	.events_discarded = client_events_discarded,
	419	.content_size = client_content_size,
	420	.packet_size = client_packet_size,
	421	.stream_id = client_stream_id,
	422	.current_timestamp = client_current_timestamp,
	423	.sequence_number = client_sequence_number,
	424	.instance_id = client_instance_id,
	425	}),
a90917c3 MD	426	.event_reserve = lttng_event_reserve,
	427	.event_commit = lttng_event_commit,
	428	.event_write_from_user = lttng_event_write_from_user,
	429	.event_memset = lttng_event_memset,
	430	.event_write = lttng_event_write,
16f78f3a	431	.event_strcpy = lttng_event_strcpy,
881833e3 MD	432	},
	433	};
	434
a90917c3	435	static int __init lttng_ring_buffer_client_init(void)
881833e3 MD	436	{
	437	/*
	438	* This vmalloc sync all also takes care of the lib ring buffer
	439	* vmalloc'd module pages when it is built as a module into LTTng.
	440	*/
263b6c88	441	wrapper_vmalloc_sync_mappings();
a90917c3	442	lttng_transport_register(&lttng_relay_transport);
881833e3 MD	443	return 0;
	444	}
	445
a90917c3	446	module_init(lttng_ring_buffer_client_init);
881833e3	447
a90917c3	448	static void __exit lttng_ring_buffer_client_exit(void)
881833e3	449	{
a90917c3	450	lttng_transport_unregister(&lttng_relay_transport);
881833e3 MD	451	}
881833e3 MD	452
a90917c3	453	module_exit(lttng_ring_buffer_client_exit);
881833e3 MD	454
881833e3 MD	455	MODULE_LICENSE("GPL and additional rights");
1c124020	456	MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
881833e3 MD	457	MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
881833e3 MD	458	" client");
1c124020 MJ	459	MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
	460	__stringify(LTTNG_MODULES_MINOR_VERSION) "."
	461	__stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
	462	LTTNG_MODULES_EXTRAVERSION);