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

/*
 * lttng-ring-buffer-client.h
 *
 * LTTng lib ring buffer client template.
 *
 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; only
 * version 2.1 of the License.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <linux/module.h>
#include <linux/types.h>
#include "wrapper/vmalloc.h"	/* for wrapper_vmalloc_sync_all() */
#include "lttng-events.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 lib_ring_buffer_config client_config;

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

static inline
unsigned char record_header_size(const struct lib_ring_buffer_config *config,
				 struct channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lib_ring_buffer_ctx *ctx)
{
	return 0;
}

#include "wrapper/ringbuffer/api.h"

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

static
size_t client_record_header_size(const struct lib_ring_buffer_config *config,
				 struct channel *chan, size_t offset,
				 size_t *pre_header_padding,
				 struct lib_ring_buffer_ctx *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 lib_ring_buffer *buf, u64 tsc,
				unsigned int subbuf_idx)
{
	struct 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_channel *lttng_chan = channel_get_private(chan);
	struct lttng_session *session = lttng_chan->session;

	header->magic = TSDL_MAGIC_NUMBER;
	memcpy(header->uuid, session->uuid.b, sizeof(session->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 lib_ring_buffer *buf, u64 tsc,
			      unsigned int subbuf_idx, unsigned long data_size)
{
	struct 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 lib_ring_buffer *buf, void *priv,
				int cpu, const char *name)
{
	return 0;
}

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

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

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

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

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

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

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

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

static const struct lib_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 channel *chan)
{
	channel_destroy(chan);
}

static
struct channel *_channel_create(const char *name,
				struct lttng_channel *lttng_chan, void *buf_addr,
				size_t subbuf_size, size_t num_subbuf,
				unsigned int switch_timer_interval,
				unsigned int read_timer_interval)
{
	struct channel *chan;

	chan = channel_create(&client_config, name, lttng_chan, 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 "LTT : 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 lib_ring_buffer *lttng_buffer_read_open(struct channel *chan)
{
	struct lib_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 channel *chan)
{
	struct lib_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 lib_ring_buffer *buf)
{
	lib_ring_buffer_release_read(buf);
}

static
int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id)
{
	return lib_ring_buffer_reserve(&client_config, ctx);
}

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

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

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

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

static
void lttng_event_strcpy(struct lib_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 channel *chan)
			     
{
	unsigned long o_begin;
	struct lib_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 channel *chan, int cpu)
{
	struct lib_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 channel *chan)
{
	return &chan->hp_wait;
}

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

static
int lttng_is_disabled(struct 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 = {
		.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,
		.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,
		.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,
	},
};

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_all();
	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");
MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
		   " client");
Commit	Line	Data
881833e3	1	/*
a90917c3	2	* lttng-ring-buffer-client.h
881833e3	3	*
881833e3 MD	4	* LTTng lib ring buffer client template.
881833e3 MD	5	*
886d51a3 MD	6	* Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	7	*
	8	* This library is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU Lesser General Public
	10	* License as published by the Free Software Foundation; only
	11	* version 2.1 of the License.
	12	*
	13	* This library is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	16	* Lesser General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU Lesser General Public
	19	* License along with this library; if not, write to the Free Software
	20	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
881833e3 MD	21	*/
	22
	23	#include <linux/module.h>
	24	#include <linux/types.h>
	25	#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
a90917c3 MD	26	#include "lttng-events.h"
a90917c3 MD	27	#include "lttng-tracer.h"
881833e3	28
dd5a0db3 MD	29	static struct lttng_transport lttng_relay_transport;
dd5a0db3 MD	30
881833e3 MD	31	struct metadata_packet_header {
881833e3 MD	32	uint32_t magic; /* 0x75D11D57 */
1ec3f75a	33	uint8_t uuid[16]; /* Unique Universal Identifier */
881833e3 MD	34	uint32_t checksum; /* 0 if unused */
	35	uint32_t content_size; /* in bits */
	36	uint32_t packet_size; /* in bits */
	37	uint8_t compression_scheme; /* 0 if unused */
	38	uint8_t encryption_scheme; /* 0 if unused */
	39	uint8_t checksum_scheme; /* 0 if unused */
4173df96 MD	40	uint8_t major; /* CTF spec major version number */
4173df96 MD	41	uint8_t minor; /* CTF spec minor version number */
881833e3 MD	42	uint8_t header_end[0];
	43	};
	44
	45	struct metadata_record_header {
	46	uint8_t header_end[0]; /* End of header */
	47	};
	48
	49	static const struct lib_ring_buffer_config client_config;
	50
	51	static inline
	52	u64 lib_ring_buffer_clock_read(struct channel *chan)
	53	{
	54	return 0;
	55	}
	56
	57	static inline
	58	unsigned char record_header_size(const struct lib_ring_buffer_config *config,
	59	struct channel *chan, size_t offset,
64c796d8	60	size_t *pre_header_padding,
881833e3 MD	61	struct lib_ring_buffer_ctx *ctx)
	62	{
	63	return 0;
	64	}
	65
	66	#include "wrapper/ringbuffer/api.h"
	67
	68	static u64 client_ring_buffer_clock_read(struct channel *chan)
	69	{
	70	return 0;
	71	}
	72
	73	static
	74	size_t client_record_header_size(const struct lib_ring_buffer_config *config,
	75	struct channel *chan, size_t offset,
881833e3	76	size_t *pre_header_padding,
881833e3 MD	77	struct lib_ring_buffer_ctx *ctx)
	78	{
	79	return 0;
	80	}
	81
	82	/**
	83	* client_packet_header_size - called on buffer-switch to a new sub-buffer
	84	*
	85	* Return header size without padding after the structure. Don't use packed
	86	* structure because gcc generates inefficient code on some architectures
	87	* (powerpc, mips..)
	88	*/
	89	static size_t client_packet_header_size(void)
	90	{
	91	return offsetof(struct metadata_packet_header, header_end);
	92	}
	93
	94	static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
	95	unsigned int subbuf_idx)
	96	{
	97	struct channel *chan = buf->backend.chan;
	98	struct metadata_packet_header *header =
	99	(struct metadata_packet_header *)
	100	lib_ring_buffer_offset_address(&buf->backend,
	101	subbuf_idx * chan->backend.subbuf_size);
a90917c3 MD	102	struct lttng_channel *lttng_chan = channel_get_private(chan);
a90917c3 MD	103	struct lttng_session *session = lttng_chan->session;
881833e3 MD	104
881833e3 MD	105	header->magic = TSDL_MAGIC_NUMBER;
1ec3f75a	106	memcpy(header->uuid, session->uuid.b, sizeof(session->uuid));
881833e3 MD	107	header->checksum = 0; /* 0 if unused */
	108	header->content_size = 0xFFFFFFFF; /* in bits, for debugging */
	109	header->packet_size = 0xFFFFFFFF; /* in bits, for debugging */
	110	header->compression_scheme = 0; /* 0 if unused */
	111	header->encryption_scheme = 0; /* 0 if unused */
	112	header->checksum_scheme = 0; /* 0 if unused */
4173df96 MD	113	header->major = CTF_SPEC_MAJOR;
4173df96 MD	114	header->minor = CTF_SPEC_MINOR;
881833e3 MD	115	}
	116
	117	/*
	118	* offset is assumed to never be 0 here : never deliver a completely empty
	119	* subbuffer. data_size is between 1 and subbuf_size.
	120	*/
	121	static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
	122	unsigned int subbuf_idx, unsigned long data_size)
	123	{
	124	struct channel *chan = buf->backend.chan;
d793d5e1	125	struct metadata_packet_header *header =
1ec3f75a	126	(struct metadata_packet_header *)
881833e3 MD	127	lib_ring_buffer_offset_address(&buf->backend,
	128	subbuf_idx * chan->backend.subbuf_size);
	129	unsigned long records_lost = 0;
	130
	131	header->content_size = data_size * CHAR_BIT; /* in bits */
	132	header->packet_size = PAGE_ALIGN(data_size) * CHAR_BIT; /* in bits */
71c1d843 MD	133	/*
	134	* We do not care about the records lost count, because the metadata
	135	* channel waits and retry.
	136	*/
	137	(void) lib_ring_buffer_get_records_lost_full(&client_config, buf);
881833e3 MD	138	records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
	139	records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
	140	WARN_ON_ONCE(records_lost != 0);
	141	}
	142
	143	static int client_buffer_create(struct lib_ring_buffer buf, void priv,
	144	int cpu, const char *name)
	145	{
	146	return 0;
	147	}
	148
	149	static void client_buffer_finalize(struct lib_ring_buffer buf, void priv, int cpu)
	150	{
	151	}
	152
3b731ab1 JD	153	static int client_timestamp_begin(const struct lib_ring_buffer_config *config,
	154	struct lib_ring_buffer buf, uint64_t timestamp_begin)
	155	{
	156	return -ENOSYS;
	157	}
	158
	159	static int client_timestamp_end(const struct lib_ring_buffer_config *config,
	160	struct lib_ring_buffer *bufb,
	161	uint64_t *timestamp_end)
	162	{
	163	return -ENOSYS;
	164	}
	165
	166	static int client_events_discarded(const struct lib_ring_buffer_config *config,
	167	struct lib_ring_buffer *bufb,
	168	uint64_t *events_discarded)
	169	{
	170	return -ENOSYS;
	171	}
	172
2348ca17 JD	173	static int client_current_timestamp(const struct lib_ring_buffer_config *config,
	174	struct lib_ring_buffer *bufb,
	175	uint64_t *ts)
	176	{
	177	return -ENOSYS;
	178	}
	179
3b731ab1 JD	180	static int client_content_size(const struct lib_ring_buffer_config *config,
	181	struct lib_ring_buffer *bufb,
	182	uint64_t *content_size)
	183	{
	184	return -ENOSYS;
	185	}
	186
	187	static int client_packet_size(const struct lib_ring_buffer_config *config,
	188	struct lib_ring_buffer *bufb,
	189	uint64_t *packet_size)
	190	{
	191	return -ENOSYS;
	192	}
	193
	194	static int client_stream_id(const struct lib_ring_buffer_config *config,
	195	struct lib_ring_buffer *bufb,
	196	uint64_t *stream_id)
	197	{
	198	return -ENOSYS;
	199	}
	200
881833e3 MD	201	static const struct lib_ring_buffer_config client_config = {
	202	.cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
	203	.cb.record_header_size = client_record_header_size,
	204	.cb.subbuffer_header_size = client_packet_header_size,
	205	.cb.buffer_begin = client_buffer_begin,
	206	.cb.buffer_end = client_buffer_end,
	207	.cb.buffer_create = client_buffer_create,
	208	.cb.buffer_finalize = client_buffer_finalize,
	209
	210	.tsc_bits = 0,
	211	.alloc = RING_BUFFER_ALLOC_GLOBAL,
	212	.sync = RING_BUFFER_SYNC_GLOBAL,
	213	.mode = RING_BUFFER_MODE_TEMPLATE,
	214	.backend = RING_BUFFER_PAGE,
2db1399a	215	.output = RING_BUFFER_OUTPUT_TEMPLATE,
881833e3 MD	216	.oops = RING_BUFFER_OOPS_CONSISTENCY,
	217	.ipi = RING_BUFFER_IPI_BARRIER,
	218	.wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
	219	};
	220
dd5a0db3 MD	221	static
	222	void release_priv_ops(void *priv_ops)
	223	{
	224	module_put(THIS_MODULE);
	225	}
	226
	227	static
	228	void lttng_channel_destroy(struct channel *chan)
	229	{
	230	channel_destroy(chan);
	231	}
	232
881833e3 MD	233	static
881833e3 MD	234	struct channel _channel_create(const char name,
a90917c3	235	struct lttng_channel lttng_chan, void buf_addr,
881833e3 MD	236	size_t subbuf_size, size_t num_subbuf,
	237	unsigned int switch_timer_interval,
	238	unsigned int read_timer_interval)
	239	{
dd5a0db3 MD	240	struct channel *chan;
	241
	242	chan = channel_create(&client_config, name, lttng_chan, buf_addr,
881833e3 MD	243	subbuf_size, num_subbuf, switch_timer_interval,
881833e3 MD	244	read_timer_interval);
dd5a0db3 MD	245	if (chan) {
	246	/*
	247	* Ensure this module is not unloaded before we finish
	248	* using lttng_relay_transport.ops.
	249	*/
	250	if (!try_module_get(THIS_MODULE)) {
	251	printk(KERN_WARNING "LTT : Can't lock transport module.\n");
	252	goto error;
	253	}
	254	chan->backend.priv_ops = &lttng_relay_transport.ops;
	255	chan->backend.release_priv_ops = release_priv_ops;
	256	}
	257	return chan;
881833e3	258
dd5a0db3 MD	259	error:
	260	lttng_channel_destroy(chan);
	261	return NULL;
881833e3 MD	262	}
	263
	264	static
a90917c3	265	struct lib_ring_buffer lttng_buffer_read_open(struct channel chan)
881833e3 MD	266	{
881833e3 MD	267	struct lib_ring_buffer *buf;
881833e3	268
cd4bd11f MD	269	buf = channel_get_ring_buffer(&client_config, chan, 0);
	270	if (!lib_ring_buffer_open_read(buf))
	271	return buf;
881833e3 MD	272	return NULL;
	273	}
	274
f71ecafa	275	static
a90917c3	276	int lttng_buffer_has_read_closed_stream(struct channel *chan)
f71ecafa MD	277	{
	278	struct lib_ring_buffer *buf;
	279	int cpu;
	280
	281	for_each_channel_cpu(cpu, chan) {
	282	buf = channel_get_ring_buffer(&client_config, chan, cpu);
	283	if (!atomic_long_read(&buf->active_readers))
	284	return 1;
	285	}
	286	return 0;
	287	}
	288
881833e3	289	static
a90917c3	290	void lttng_buffer_read_close(struct lib_ring_buffer *buf)
881833e3 MD	291	{
881833e3 MD	292	lib_ring_buffer_release_read(buf);
881833e3 MD	293	}
881833e3 MD	294
c099397a	295	static
a90917c3	296	int lttng_event_reserve(struct lib_ring_buffer_ctx *ctx, uint32_t event_id)
881833e3 MD	297	{
	298	return lib_ring_buffer_reserve(&client_config, ctx);
	299	}
	300
c099397a	301	static
a90917c3	302	void lttng_event_commit(struct lib_ring_buffer_ctx *ctx)
881833e3 MD	303	{
	304	lib_ring_buffer_commit(&client_config, ctx);
	305	}
	306
c099397a	307	static
a90917c3	308	void lttng_event_write(struct lib_ring_buffer_ctx ctx, const void src,
881833e3 MD	309	size_t len)
	310	{
	311	lib_ring_buffer_write(&client_config, ctx, src, len);
	312	}
	313
4ea00e4f	314	static
a90917c3	315	void lttng_event_write_from_user(struct lib_ring_buffer_ctx *ctx,
4ea00e4f JD	316	const void __user *src, size_t len)
4ea00e4f JD	317	{
7b8ea3a5	318	lib_ring_buffer_copy_from_user_inatomic(&client_config, ctx, src, len);
4ea00e4f JD	319	}
4ea00e4f JD	320
58aa5d24	321	static
a90917c3	322	void lttng_event_memset(struct lib_ring_buffer_ctx *ctx,
58aa5d24 MD	323	int c, size_t len)
	324	{
	325	lib_ring_buffer_memset(&client_config, ctx, c, len);
	326	}
	327
16f78f3a MD	328	static
	329	void lttng_event_strcpy(struct lib_ring_buffer_ctx ctx, const char src,
	330	size_t len)
	331	{
	332	lib_ring_buffer_strcpy(&client_config, ctx, src, len, '#');
	333	}
	334
1ec3f75a	335	static
a90917c3	336	size_t lttng_packet_avail_size(struct channel *chan)
1ec3f75a MD	337
	338	{
	339	unsigned long o_begin;
	340	struct lib_ring_buffer *buf;
	341
	342	buf = chan->backend.buf; /* Only for global buffer ! */
	343	o_begin = v_read(&client_config, &buf->offset);
	344	if (subbuf_offset(o_begin, chan) != 0) {
	345	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan);
	346	} else {
	347	return chan->backend.subbuf_size - subbuf_offset(o_begin, chan)
	348	- sizeof(struct metadata_packet_header);
	349	}
	350	}
	351
c099397a	352	static
a90917c3	353	wait_queue_head_t lttng_get_writer_buf_wait_queue(struct channel chan, int cpu)
c099397a	354	{
71c1d843 MD	355	struct lib_ring_buffer *buf = channel_get_ring_buffer(&client_config,
	356	chan, cpu);
	357	return &buf->write_wait;
24cedcfe MD	358	}
	359
	360	static
a90917c3	361	wait_queue_head_t lttng_get_hp_wait_queue(struct channel chan)
24cedcfe MD	362	{
	363	return &chan->hp_wait;
	364	}
	365
	366	static
a90917c3	367	int lttng_is_finalized(struct channel *chan)
24cedcfe MD	368	{
24cedcfe MD	369	return lib_ring_buffer_channel_is_finalized(chan);
c099397a MD	370	}
c099397a MD	371
254ec7bc	372	static
a90917c3	373	int lttng_is_disabled(struct channel *chan)
254ec7bc MD	374	{
	375	return lib_ring_buffer_channel_is_disabled(chan);
	376	}
	377
a90917c3	378	static struct lttng_transport lttng_relay_transport = {
881833e3 MD	379	.name = "relay-" RING_BUFFER_MODE_TEMPLATE_STRING,
	380	.owner = THIS_MODULE,
	381	.ops = {
	382	.channel_create = _channel_create,
a90917c3 MD	383	.channel_destroy = lttng_channel_destroy,
a90917c3 MD	384	.buffer_read_open = lttng_buffer_read_open,
f71ecafa	385	.buffer_has_read_closed_stream =
a90917c3 MD	386	lttng_buffer_has_read_closed_stream,
	387	.buffer_read_close = lttng_buffer_read_close,
	388	.event_reserve = lttng_event_reserve,
	389	.event_commit = lttng_event_commit,
	390	.event_write_from_user = lttng_event_write_from_user,
	391	.event_memset = lttng_event_memset,
	392	.event_write = lttng_event_write,
16f78f3a	393	.event_strcpy = lttng_event_strcpy,
a90917c3 MD	394	.packet_avail_size = lttng_packet_avail_size,
	395	.get_writer_buf_wait_queue = lttng_get_writer_buf_wait_queue,
	396	.get_hp_wait_queue = lttng_get_hp_wait_queue,
	397	.is_finalized = lttng_is_finalized,
	398	.is_disabled = lttng_is_disabled,
67a80835 MD	399	.timestamp_begin = client_timestamp_begin,
	400	.timestamp_end = client_timestamp_end,
	401	.events_discarded = client_events_discarded,
	402	.content_size = client_content_size,
	403	.packet_size = client_packet_size,
	404	.stream_id = client_stream_id,
	405	.current_timestamp = client_current_timestamp,
881833e3 MD	406	},
	407	};
	408
a90917c3	409	static int __init lttng_ring_buffer_client_init(void)
881833e3 MD	410	{
	411	/*
	412	* This vmalloc sync all also takes care of the lib ring buffer
	413	* vmalloc'd module pages when it is built as a module into LTTng.
	414	*/
	415	wrapper_vmalloc_sync_all();
a90917c3	416	lttng_transport_register(&lttng_relay_transport);
881833e3 MD	417	return 0;
	418	}
	419
a90917c3	420	module_init(lttng_ring_buffer_client_init);
881833e3	421
a90917c3	422	static void __exit lttng_ring_buffer_client_exit(void)
881833e3	423	{
a90917c3	424	lttng_transport_unregister(&lttng_relay_transport);
881833e3 MD	425	}
881833e3 MD	426
a90917c3	427	module_exit(lttng_ring_buffer_client_exit);
881833e3 MD	428
	429	MODULE_LICENSE("GPL and additional rights");
	430	MODULE_AUTHOR("Mathieu Desnoyers");
	431	MODULE_DESCRIPTION("LTTng ring buffer " RING_BUFFER_MODE_TEMPLATE_STRING
	432	" client");