[lttng-modules.git] / src / lttng-context-egid.c

/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
 *
 * lttng-context-egid.c
 *
 * LTTng effective group ID context.
 *
 * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *               2019 Michael Jeanson <mjeanson@efficios.com>
 *
 */

#include <linux/module.h>
#include <linux/sched.h>
#include <lttng/events.h>
#include <lttng/events-internal.h>
#include <lttng/tracer.h>
#include <ringbuffer/frontend_types.h>
#include <wrapper/vmalloc.h>
#include <wrapper/user_namespace.h>

static
size_t egid_get_size(void *priv, struct lttng_probe_ctx *probe_ctx, size_t offset)
{
	size_t size = 0;

	size += lib_ring_buffer_align(offset, lttng_alignof(gid_t));
	size += sizeof(gid_t);
	return size;
}

static
void egid_record(void *priv, struct lttng_probe_ctx *probe_ctx,
		 struct lib_ring_buffer_ctx *ctx,
		 struct lttng_channel *chan)
{
	gid_t egid;

	egid = lttng_current_egid();
	lib_ring_buffer_align_ctx(ctx, lttng_alignof(egid));
	chan->ops->event_write(ctx, &egid, sizeof(egid));
}

static
void egid_get_value(void *priv,
		struct lttng_probe_ctx *lttng_probe_ctx,
		struct lttng_ctx_value *value)
{
	value->u.s64 = lttng_current_egid();
}

static const struct lttng_kernel_ctx_field *ctx_field = lttng_kernel_static_ctx_field(
	lttng_kernel_static_event_field("egid",
		lttng_kernel_static_type_integer_from_type(gid_t, __BYTE_ORDER, 10),
		false, false, false),
	egid_get_size,
	egid_record,
	egid_get_value,
	NULL, NULL);

int lttng_add_egid_to_ctx(struct lttng_kernel_ctx **ctx)
{
	int ret;

	if (lttng_kernel_find_context(*ctx, ctx_field->event_field->name))
		return -EEXIST;
	ret = lttng_kernel_context_append(ctx, ctx_field);
	wrapper_vmalloc_sync_mappings();
	return ret;
}
EXPORT_SYMBOL_GPL(lttng_add_egid_to_ctx);
Commit	Line	Data
	1	/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
	2	*
	3	* lttng-context-egid.c
	4	*
	5	* LTTng effective group ID context.
	6	*
	7	* Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	8	* 2019 Michael Jeanson <mjeanson@efficios.com>
	9	*
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/sched.h>
	14	#include <lttng/events.h>
	15	#include <lttng/events-internal.h>
	16	#include <lttng/tracer.h>
	17	#include <ringbuffer/frontend_types.h>
	18	#include <wrapper/vmalloc.h>
	19	#include <wrapper/user_namespace.h>
	20
	21	static
	22	size_t egid_get_size(void priv, struct lttng_probe_ctx probe_ctx, size_t offset)
	23	{
	24	size_t size = 0;
	25
	26	size += lib_ring_buffer_align(offset, lttng_alignof(gid_t));
	27	size += sizeof(gid_t);
	28	return size;
	29	}
	30
	31	static
	32	void egid_record(void priv, struct lttng_probe_ctx probe_ctx,
	33	struct lib_ring_buffer_ctx *ctx,
	34	struct lttng_channel *chan)
	35	{
	36	gid_t egid;
	37
	38	egid = lttng_current_egid();
	39	lib_ring_buffer_align_ctx(ctx, lttng_alignof(egid));
	40	chan->ops->event_write(ctx, &egid, sizeof(egid));
	41	}
	42
	43	static
	44	void egid_get_value(void *priv,
	45	struct lttng_probe_ctx *lttng_probe_ctx,
	46	struct lttng_ctx_value *value)
	47	{
	48	value->u.s64 = lttng_current_egid();
	49	}
	50
	51	static const struct lttng_kernel_ctx_field *ctx_field = lttng_kernel_static_ctx_field(
	52	lttng_kernel_static_event_field("egid",
	53	lttng_kernel_static_type_integer_from_type(gid_t, __BYTE_ORDER, 10),
	54	false, false, false),
	55	egid_get_size,
	56	egid_record,
	57	egid_get_value,
	58	NULL, NULL);
	59
	60	int lttng_add_egid_to_ctx(struct lttng_kernel_ctx **ctx)
	61	{
	62	int ret;
	63
	64	if (lttng_kernel_find_context(*ctx, ctx_field->event_field->name))
	65	return -EEXIST;
	66	ret = lttng_kernel_context_append(ctx, ctx_field);
	67	wrapper_vmalloc_sync_mappings();
	68	return ret;
	69	}
	70	EXPORT_SYMBOL_GPL(lttng_add_egid_to_ctx);