[lttng-modules.git] / src / probes / lttng-uprobes.c

/* SPDX-License-Identifier: (GPL-2.0-only OR LGPL-2.1-only)
 *
 * probes/lttng-uprobes.c
 *
 * LTTng uprobes integration module.
 *
 * Copyright (C) 2013 Yannick Brosseau <yannick.brosseau@gmail.com>
 * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 *
 */

#include <wrapper/fdtable.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/namei.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <lttng/events.h>
#include <lttng/events-internal.h>
#include <lttng/tracer.h>
#include <wrapper/irqflags.h>
#include <ringbuffer/frontend_types.h>
#include <wrapper/uprobes.h>
#include <wrapper/vmalloc.h>

static
int lttng_uprobes_event_handler_pre(struct uprobe_consumer *uc, struct pt_regs *regs)
{
	struct lttng_uprobe_handler *uprobe_handler =
		container_of(uc, struct lttng_uprobe_handler, up_consumer);
	struct lttng_kernel_event_recorder *event_recorder = uprobe_handler->u.event;
	struct lttng_probe_ctx lttng_probe_ctx = {
		.event = event_recorder,
		.interruptible = !lttng_regs_irqs_disabled(regs),
	};
	struct lttng_channel *chan = event_recorder->chan;
	struct lib_ring_buffer_ctx ctx;
	int ret;

	struct {
		unsigned long ip;
	} payload;

	if (unlikely(!LTTNG_READ_ONCE(chan->session->active)))
		return 0;
	if (unlikely(!LTTNG_READ_ONCE(chan->enabled)))
		return 0;
	if (unlikely(!LTTNG_READ_ONCE(event_recorder->parent.enabled)))
		return 0;

	lib_ring_buffer_ctx_init(&ctx, chan->chan, &lttng_probe_ctx,
		sizeof(payload), lttng_alignof(payload), -1);

	ret = chan->ops->event_reserve(&ctx, event_recorder->priv->id);
	if (ret < 0)
		return 0;

	/* Event payload. */
	payload.ip = (unsigned long)instruction_pointer(regs);

	lib_ring_buffer_align_ctx(&ctx, lttng_alignof(payload));
	chan->ops->event_write(&ctx, &payload, sizeof(payload));
	chan->ops->event_commit(&ctx);
	return 0;
}

static
int lttng_uprobes_event_notifier_handler_pre(struct uprobe_consumer *uc, struct pt_regs *regs)
{
	struct lttng_uprobe_handler *uprobe_handler =
		container_of(uc, struct lttng_uprobe_handler, up_consumer);
	struct lttng_kernel_event_notifier *event_notifier = uprobe_handler->u.event_notifier;
	struct lttng_kernel_notification_ctx notif_ctx;

	if (unlikely(!READ_ONCE(event_notifier->parent.enabled)))
		return 0;

	notif_ctx.eval_capture = LTTNG_READ_ONCE(event_notifier->eval_capture);
	event_notifier->notification_send(event_notifier, NULL, NULL, &notif_ctx);
	return 0;
}

static const struct lttng_kernel_type_common *event_type =
	lttng_kernel_static_type_integer_from_type(unsigned long, __BYTE_ORDER, 16);

/*
 * Create event description.
 */
static
int lttng_create_uprobe_event(const char *name, struct lttng_kernel_event_recorder *event_recorder)
{
	const struct lttng_kernel_event_field **fieldp_array;
	struct lttng_kernel_event_field *field;
	struct lttng_kernel_event_desc *desc;
	int ret;

	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
	if (!desc)
		return -ENOMEM;
	desc->event_name = kstrdup(name, GFP_KERNEL);
	if (!desc->event_name) {
		ret = -ENOMEM;
		goto error_str;
	}
	desc->nr_fields = 1;
	fieldp_array = kzalloc(1 * sizeof(struct lttng_kernel_event_field *), GFP_KERNEL);
	if (!fieldp_array) {
		ret = -ENOMEM;
		goto error_fieldp_array;
	}
	desc->fields = fieldp_array;
	desc->fields[0] = field =
		kzalloc(sizeof(struct lttng_kernel_event_field), GFP_KERNEL);
	if (!field) {
		ret = -ENOMEM;
		goto error_field;
	}
	field->name = "ip";
	field->type = event_type;
	desc->owner = THIS_MODULE;
	event_recorder->priv->parent.desc = desc;

	return 0;

error_field:
	kfree(fieldp_array);
error_fieldp_array:
	kfree(desc->event_name);
error_str:
	kfree(desc);
	return ret;
}

/*
 * Create event_notifier description.
 */
static
int lttng_create_uprobe_event_notifier(const char *name, struct lttng_kernel_event_notifier *event_notifier)
{
	struct lttng_kernel_event_desc *desc;
	int ret;

	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
	if (!desc)
		return -ENOMEM;
	desc->event_name = kstrdup(name, GFP_KERNEL);
	if (!desc->event_name) {
		ret = -ENOMEM;
		goto error_str;
	}

	desc->nr_fields = 0;

	desc->owner = THIS_MODULE;
	event_notifier->priv->parent.desc = desc;

	return 0;

error_str:
	kfree(desc);
	return ret;
}

/*
 * Returns the inode struct from the current task and an fd. The inode is
 * grabbed by this function and must be put once we are done with it using
 * iput().
 */
static struct inode *get_inode_from_fd(int fd)
{
	struct file *file;
	struct inode *inode;

	rcu_read_lock();
	/*
	 * Returns the file backing the given fd. Needs to be done inside an RCU
	 * critical section.
	 */
	file = lttng_lookup_fd_rcu(fd);
	if (file == NULL) {
		printk(KERN_WARNING "LTTng: Cannot access file backing the fd(%d)\n", fd);
		inode = NULL;
		goto error;
	}

	/* Grab a reference on the inode. */
	inode = igrab(file->f_path.dentry->d_inode);
	if (inode == NULL)
		printk(KERN_WARNING "LTTng: Cannot grab a reference on the inode.\n");
error:
	rcu_read_unlock();
	return inode;
}


static
int lttng_uprobes_add_callsite(struct lttng_uprobe *uprobe,
	struct lttng_kernel_abi_event_callsite __user *callsite,
	int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs),
	void *priv_data)
{
	int ret = 0;
	struct lttng_uprobe_handler *uprobe_handler;

	if (!priv_data) {
		ret = -EINVAL;
		goto end;
	}

	uprobe_handler = kzalloc(sizeof(struct lttng_uprobe_handler), GFP_KERNEL);
	if (!uprobe_handler) {
		printk(KERN_WARNING "LTTng: Error allocating uprobe_handler");
		ret = -ENOMEM;
		goto end;
	}

	/* Ensure the memory we just allocated don't notify page faults. */
	wrapper_vmalloc_sync_mappings();

	uprobe_handler->u.event = priv_data;
	uprobe_handler->up_consumer.handler = handler;

	ret = copy_from_user(&uprobe_handler->offset, &callsite->u.uprobe.offset, sizeof(uint64_t));
	if (ret) {
		goto register_error;
	}

	ret = wrapper_uprobe_register(uprobe->inode,
		      uprobe_handler->offset, &uprobe_handler->up_consumer);
	if (ret) {
		printk(KERN_WARNING "LTTng: Error registering probe on inode %lu "
		       "and offset 0x%llx\n", uprobe->inode->i_ino,
		       uprobe_handler->offset);
		ret = -1;
		goto register_error;
	}

	list_add(&uprobe_handler->node, &uprobe->head);

	return ret;

register_error:
	kfree(uprobe_handler);
end:
	return ret;
}

int lttng_uprobes_event_add_callsite(struct lttng_kernel_event_recorder *event_recorder,
	struct lttng_kernel_abi_event_callsite __user *callsite)
{
	return lttng_uprobes_add_callsite(&event_recorder->priv->parent.u.uprobe, callsite,
		lttng_uprobes_event_handler_pre, event_recorder);
}
EXPORT_SYMBOL_GPL(lttng_uprobes_event_add_callsite);

int lttng_uprobes_event_notifier_add_callsite(struct lttng_kernel_event_notifier *event_notifier,
	struct lttng_kernel_abi_event_callsite __user *callsite)
{
	return lttng_uprobes_add_callsite(&event_notifier->priv->parent.u.uprobe, callsite,
		lttng_uprobes_event_notifier_handler_pre, event_notifier);
}
EXPORT_SYMBOL_GPL(lttng_uprobes_event_notifier_add_callsite);

static
int lttng_uprobes_register(struct lttng_uprobe *uprobe, int fd)
{
	int ret = 0;
	struct inode *inode;

	inode = get_inode_from_fd(fd);
	if (!inode) {
		printk(KERN_WARNING "LTTng: Cannot get inode from fd\n");
		ret = -EBADF;
		goto inode_error;
	}
	uprobe->inode = inode;
	INIT_LIST_HEAD(&uprobe->head);

inode_error:
	return ret;
}

int lttng_uprobes_register_event(const char *name, int fd, struct lttng_kernel_event_recorder *event_recorder)
{
	int ret = 0;

	ret = lttng_create_uprobe_event(name, event_recorder);
	if (ret)
		goto error;

	ret = lttng_uprobes_register(&event_recorder->priv->parent.u.uprobe, fd);
	if (ret)
		goto register_error;

	return 0;

register_error:
	kfree(event_recorder->priv->parent.desc->event_name);
	kfree(event_recorder->priv->parent.desc);
error:
	return ret;
}
EXPORT_SYMBOL_GPL(lttng_uprobes_register_event);

int lttng_uprobes_register_event_notifier(const char *name, int fd,
		struct lttng_kernel_event_notifier *event_notifier)
{
	int ret = 0;

	ret = lttng_create_uprobe_event_notifier(name, event_notifier);
	if (ret)
		goto error;

	ret = lttng_uprobes_register(&event_notifier->priv->parent.u.uprobe, fd);
	if (ret)
		goto register_error;

	return 0;

register_error:
	kfree(event_notifier->priv->parent.desc->event_name);
	kfree(event_notifier->priv->parent.desc);
error:
	return ret;
}
EXPORT_SYMBOL_GPL(lttng_uprobes_register_event_notifier);

static
void lttng_uprobes_unregister(struct inode *inode, struct list_head *head)
{
	struct lttng_uprobe_handler *iter, *tmp;

	/*
	 * Iterate over the list of handler, remove each handler from the list
	 * and free the struct.
	 */
	list_for_each_entry_safe(iter, tmp, head, node) {
		wrapper_uprobe_unregister(inode, iter->offset, &iter->up_consumer);
		list_del(&iter->node);
		kfree(iter);
	}

}

void lttng_uprobes_unregister_event(struct lttng_kernel_event_recorder *event_recorder)
{
	lttng_uprobes_unregister(event_recorder->priv->parent.u.uprobe.inode, &event_recorder->priv->parent.u.uprobe.head);
}
EXPORT_SYMBOL_GPL(lttng_uprobes_unregister_event);

void lttng_uprobes_unregister_event_notifier(struct lttng_kernel_event_notifier *event_notifier)
{
	lttng_uprobes_unregister(event_notifier->priv->parent.u.uprobe.inode, &event_notifier->priv->parent.u.uprobe.head);
}
EXPORT_SYMBOL_GPL(lttng_uprobes_unregister_event_notifier);

void lttng_uprobes_destroy_event_private(struct lttng_kernel_event_recorder *event_recorder)
{
	iput(event_recorder->priv->parent.u.uprobe.inode);
	kfree(event_recorder->priv->parent.desc->fields[0]);
	kfree(event_recorder->priv->parent.desc->fields);
	kfree(event_recorder->priv->parent.desc->event_name);
	kfree(event_recorder->priv->parent.desc);
}
EXPORT_SYMBOL_GPL(lttng_uprobes_destroy_event_private);

void lttng_uprobes_destroy_event_notifier_private(struct lttng_kernel_event_notifier *event_notifier)
{
	iput(event_notifier->priv->parent.u.uprobe.inode);
	kfree(event_notifier->priv->parent.desc->event_name);
	kfree(event_notifier->priv->parent.desc);
}
EXPORT_SYMBOL_GPL(lttng_uprobes_destroy_event_notifier_private);

MODULE_LICENSE("GPL and additional rights");
MODULE_AUTHOR("Yannick Brosseau");
MODULE_DESCRIPTION("Linux Trace Toolkit Uprobes Support");
Commit	Line	Data
b7cdc182	1	/* SPDX-License-Identifier: (GPL-2.0-only OR LGPL-2.1-only)
8134eb60	2	*
149b9a9d YB	3	* probes/lttng-uprobes.c
	4	*
	5	* LTTng uprobes integration module.
	6	*
	7	* Copyright (C) 2013 Yannick Brosseau <yannick.brosseau@gmail.com>
	8	* Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
	9	*
149b9a9d YB	10	*/
149b9a9d YB	11
0aebcd68	12	#include <wrapper/fdtable.h>
3aed4dca	13	#include <linux/list.h>
149b9a9d YB	14	#include <linux/module.h>
	15	#include <linux/namei.h>
	16	#include <linux/slab.h>
3aed4dca	17	#include <linux/uaccess.h>
2df37e95	18	#include <lttng/events.h>
a67ba386	19	#include <lttng/events-internal.h>
2df37e95	20	#include <lttng/tracer.h>
149b9a9d	21	#include <wrapper/irqflags.h>
24591303	22	#include <ringbuffer/frontend_types.h>
149b9a9d YB	23	#include <wrapper/uprobes.h>
	24	#include <wrapper/vmalloc.h>
	25
	26	static
83b802dc	27	int lttng_uprobes_event_handler_pre(struct uprobe_consumer uc, struct pt_regs regs)
149b9a9d	28	{
3aed4dca FD	29	struct lttng_uprobe_handler *uprobe_handler =
3aed4dca FD	30	container_of(uc, struct lttng_uprobe_handler, up_consumer);
a67ba386	31	struct lttng_kernel_event_recorder *event_recorder = uprobe_handler->u.event;
149b9a9d	32	struct lttng_probe_ctx lttng_probe_ctx = {
a67ba386	33	.event = event_recorder,
149b9a9d YB	34	.interruptible = !lttng_regs_irqs_disabled(regs),
149b9a9d YB	35	};
a67ba386	36	struct lttng_channel *chan = event_recorder->chan;
149b9a9d YB	37	struct lib_ring_buffer_ctx ctx;
	38	int ret;
	39
	40	struct {
	41	unsigned long ip;
56377c91	42	} payload;
149b9a9d	43
585e5dcc	44	if (unlikely(!LTTNG_READ_ONCE(chan->session->active)))
149b9a9d	45	return 0;
585e5dcc	46	if (unlikely(!LTTNG_READ_ONCE(chan->enabled)))
149b9a9d	47	return 0;
a67ba386	48	if (unlikely(!LTTNG_READ_ONCE(event_recorder->parent.enabled)))
149b9a9d YB	49	return 0;
	50
	51	lib_ring_buffer_ctx_init(&ctx, chan->chan, &lttng_probe_ctx,
	52	sizeof(payload), lttng_alignof(payload), -1);
	53
a67ba386	54	ret = chan->ops->event_reserve(&ctx, event_recorder->priv->id);
149b9a9d YB	55	if (ret < 0)
	56	return 0;
	57
	58	/* Event payload. */
7445d54f	59	payload.ip = (unsigned long)instruction_pointer(regs);
56377c91	60
149b9a9d YB	61	lib_ring_buffer_align_ctx(&ctx, lttng_alignof(payload));
	62	chan->ops->event_write(&ctx, &payload, sizeof(payload));
	63	chan->ops->event_commit(&ctx);
	64	return 0;
	65	}
	66
9de67196 FD	67	static
	68	int lttng_uprobes_event_notifier_handler_pre(struct uprobe_consumer uc, struct pt_regs regs)
	69	{
	70	struct lttng_uprobe_handler *uprobe_handler =
	71	container_of(uc, struct lttng_uprobe_handler, up_consumer);
a67ba386 MD	72	struct lttng_kernel_event_notifier *event_notifier = uprobe_handler->u.event_notifier;
a67ba386 MD	73	struct lttng_kernel_notification_ctx notif_ctx;
9de67196	74
a67ba386	75	if (unlikely(!READ_ONCE(event_notifier->parent.enabled)))
9de67196 FD	76	return 0;
9de67196 FD	77
c3eddb2e	78	notif_ctx.eval_capture = LTTNG_READ_ONCE(event_notifier->eval_capture);
a67ba386	79	event_notifier->notification_send(event_notifier, NULL, NULL, &notif_ctx);
9de67196 FD	80	return 0;
	81	}
	82
437d5aa5 MD	83	static const struct lttng_kernel_type_common *event_type =
	84	lttng_kernel_static_type_integer_from_type(unsigned long, __BYTE_ORDER, 16);
	85
149b9a9d YB	86	/*
	87	* Create event description.
	88	*/
	89	static
a67ba386	90	int lttng_create_uprobe_event(const char name, struct lttng_kernel_event_recorder event_recorder)
149b9a9d	91	{
437d5aa5 MD	92	const struct lttng_kernel_event_field **fieldp_array;
	93	struct lttng_kernel_event_field *field;
	94	struct lttng_kernel_event_desc *desc;
149b9a9d YB	95	int ret;
149b9a9d YB	96
437d5aa5	97	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
149b9a9d YB	98	if (!desc)
149b9a9d YB	99	return -ENOMEM;
437d5aa5 MD	100	desc->event_name = kstrdup(name, GFP_KERNEL);
437d5aa5 MD	101	if (!desc->event_name) {
149b9a9d YB	102	ret = -ENOMEM;
	103	goto error_str;
	104	}
149b9a9d	105	desc->nr_fields = 1;
437d5aa5 MD	106	fieldp_array = kzalloc(1 * sizeof(struct lttng_kernel_event_field *), GFP_KERNEL);
437d5aa5 MD	107	if (!fieldp_array) {
149b9a9d	108	ret = -ENOMEM;
437d5aa5	109	goto error_fieldp_array;
149b9a9d	110	}
437d5aa5 MD	111	desc->fields = fieldp_array;
	112	desc->fields[0] = field =
	113	kzalloc(sizeof(struct lttng_kernel_event_field), GFP_KERNEL);
	114	if (!field) {
	115	ret = -ENOMEM;
	116	goto error_field;
	117	}
	118	field->name = "ip";
	119	field->type = event_type;
149b9a9d	120	desc->owner = THIS_MODULE;
a67ba386	121	event_recorder->priv->parent.desc = desc;
149b9a9d YB	122
	123	return 0;
	124
437d5aa5 MD	125	error_field:
	126	kfree(fieldp_array);
	127	error_fieldp_array:
	128	kfree(desc->event_name);
149b9a9d YB	129	error_str:
	130	kfree(desc);
	131	return ret;
	132	}
	133
9de67196 FD	134	/*
	135	* Create event_notifier description.
	136	*/
	137	static
a67ba386	138	int lttng_create_uprobe_event_notifier(const char name, struct lttng_kernel_event_notifier event_notifier)
9de67196	139	{
437d5aa5	140	struct lttng_kernel_event_desc *desc;
9de67196 FD	141	int ret;
9de67196 FD	142
437d5aa5	143	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
9de67196 FD	144	if (!desc)
9de67196 FD	145	return -ENOMEM;
437d5aa5 MD	146	desc->event_name = kstrdup(name, GFP_KERNEL);
437d5aa5 MD	147	if (!desc->event_name) {
9de67196 FD	148	ret = -ENOMEM;
	149	goto error_str;
	150	}
	151
	152	desc->nr_fields = 0;
	153
	154	desc->owner = THIS_MODULE;
a67ba386	155	event_notifier->priv->parent.desc = desc;
9de67196 FD	156
	157	return 0;
	158
	159	error_str:
	160	kfree(desc);
	161	return ret;
	162	}
	163
56377c91 FD	164	/*
	165	* Returns the inode struct from the current task and an fd. The inode is
	166	* grabbed by this function and must be put once we are done with it using
	167	* iput().
	168	*/
	169	static struct inode *get_inode_from_fd(int fd)
	170	{
	171	struct file *file;
	172	struct inode *inode;
	173
	174	rcu_read_lock();
	175	/*
	176	* Returns the file backing the given fd. Needs to be done inside an RCU
	177	* critical section.
	178	*/
0aebcd68	179	file = lttng_lookup_fd_rcu(fd);
56377c91	180	if (file == NULL) {
5a15f70c	181	printk(KERN_WARNING "LTTng: Cannot access file backing the fd(%d)\n", fd);
56377c91 FD	182	inode = NULL;
	183	goto error;
	184	}
	185
	186	/* Grab a reference on the inode. */
	187	inode = igrab(file->f_path.dentry->d_inode);
	188	if (inode == NULL)
5a15f70c	189	printk(KERN_WARNING "LTTng: Cannot grab a reference on the inode.\n");
56377c91 FD	190	error:
	191	rcu_read_unlock();
	192	return inode;
	193	}
	194
83b802dc FD	195
	196	static
	197	int lttng_uprobes_add_callsite(struct lttng_uprobe *uprobe,
606828e4	198	struct lttng_kernel_abi_event_callsite __user *callsite,
83b802dc FD	199	int (handler)(struct uprobe_consumer self, struct pt_regs *regs),
83b802dc FD	200	void *priv_data)
149b9a9d	201	{
3aed4dca FD	202	int ret = 0;
	203	struct lttng_uprobe_handler *uprobe_handler;
	204
83b802dc	205	if (!priv_data) {
3aed4dca FD	206	ret = -EINVAL;
	207	goto end;
	208	}
	209
	210	uprobe_handler = kzalloc(sizeof(struct lttng_uprobe_handler), GFP_KERNEL);
	211	if (!uprobe_handler) {
5a15f70c	212	printk(KERN_WARNING "LTTng: Error allocating uprobe_handler");
3aed4dca FD	213	ret = -ENOMEM;
	214	goto end;
	215	}
	216
196bfc6a	217	/* Ensure the memory we just allocated don't notify page faults. */
263b6c88	218	wrapper_vmalloc_sync_mappings();
3aed4dca	219
83b802dc FD	220	uprobe_handler->u.event = priv_data;
83b802dc FD	221	uprobe_handler->up_consumer.handler = handler;
3aed4dca FD	222
	223	ret = copy_from_user(&uprobe_handler->offset, &callsite->u.uprobe.offset, sizeof(uint64_t));
	224	if (ret) {
	225	goto register_error;
	226	}
	227
83b802dc	228	ret = wrapper_uprobe_register(uprobe->inode,
3aed4dca FD	229	uprobe_handler->offset, &uprobe_handler->up_consumer);
3aed4dca FD	230	if (ret) {
5a15f70c	231	printk(KERN_WARNING "LTTng: Error registering probe on inode %lu "
83b802dc	232	"and offset 0x%llx\n", uprobe->inode->i_ino,
3aed4dca FD	233	uprobe_handler->offset);
	234	ret = -1;
	235	goto register_error;
	236	}
	237
83b802dc	238	list_add(&uprobe_handler->node, &uprobe->head);
3aed4dca FD	239
	240	return ret;
	241
	242	register_error:
	243	kfree(uprobe_handler);
	244	end:
	245	return ret;
	246	}
3aed4dca	247
a67ba386	248	int lttng_uprobes_event_add_callsite(struct lttng_kernel_event_recorder *event_recorder,
606828e4	249	struct lttng_kernel_abi_event_callsite __user *callsite)
83b802dc	250	{
a67ba386 MD	251	return lttng_uprobes_add_callsite(&event_recorder->priv->parent.u.uprobe, callsite,
a67ba386 MD	252	lttng_uprobes_event_handler_pre, event_recorder);
83b802dc FD	253	}
	254	EXPORT_SYMBOL_GPL(lttng_uprobes_event_add_callsite);
	255
a67ba386	256	int lttng_uprobes_event_notifier_add_callsite(struct lttng_kernel_event_notifier *event_notifier,
606828e4	257	struct lttng_kernel_abi_event_callsite __user *callsite)
9de67196	258	{
a67ba386	259	return lttng_uprobes_add_callsite(&event_notifier->priv->parent.u.uprobe, callsite,
9de67196 FD	260	lttng_uprobes_event_notifier_handler_pre, event_notifier);
	261	}
	262	EXPORT_SYMBOL_GPL(lttng_uprobes_event_notifier_add_callsite);
	263
83b802dc FD	264	static
83b802dc FD	265	int lttng_uprobes_register(struct lttng_uprobe *uprobe, int fd)
3aed4dca FD	266	{
3aed4dca FD	267	int ret = 0;
56377c91	268	struct inode *inode;
149b9a9d	269
56377c91 FD	270	inode = get_inode_from_fd(fd);
56377c91 FD	271	if (!inode) {
5a15f70c	272	printk(KERN_WARNING "LTTng: Cannot get inode from fd\n");
56377c91 FD	273	ret = -EBADF;
	274	goto inode_error;
	275	}
83b802dc FD	276	uprobe->inode = inode;
	277	INIT_LIST_HEAD(&uprobe->head);
	278
	279	inode_error:
	280	return ret;
	281	}
	282
a67ba386	283	int lttng_uprobes_register_event(const char name, int fd, struct lttng_kernel_event_recorder event_recorder)
83b802dc FD	284	{
	285	int ret = 0;
	286
a67ba386	287	ret = lttng_create_uprobe_event(name, event_recorder);
83b802dc FD	288	if (ret)
	289	goto error;
	290
a67ba386	291	ret = lttng_uprobes_register(&event_recorder->priv->parent.u.uprobe, fd);
83b802dc FD	292	if (ret)
83b802dc FD	293	goto register_error;
149b9a9d	294
149b9a9d YB	295	return 0;
149b9a9d YB	296
83b802dc	297	register_error:
a67ba386 MD	298	kfree(event_recorder->priv->parent.desc->event_name);
a67ba386 MD	299	kfree(event_recorder->priv->parent.desc);
149b9a9d YB	300	error:
	301	return ret;
	302	}
83b802dc	303	EXPORT_SYMBOL_GPL(lttng_uprobes_register_event);
149b9a9d	304
9de67196	305	int lttng_uprobes_register_event_notifier(const char *name, int fd,
a67ba386	306	struct lttng_kernel_event_notifier *event_notifier)
9de67196 FD	307	{
	308	int ret = 0;
	309
	310	ret = lttng_create_uprobe_event_notifier(name, event_notifier);
	311	if (ret)
	312	goto error;
	313
a67ba386	314	ret = lttng_uprobes_register(&event_notifier->priv->parent.u.uprobe, fd);
9de67196 FD	315	if (ret)
	316	goto register_error;
	317
	318	return 0;
	319
	320	register_error:
a67ba386 MD	321	kfree(event_notifier->priv->parent.desc->event_name);
a67ba386 MD	322	kfree(event_notifier->priv->parent.desc);
9de67196 FD	323	error:
	324	return ret;
	325	}
	326	EXPORT_SYMBOL_GPL(lttng_uprobes_register_event_notifier);
	327
	328	static
	329	void lttng_uprobes_unregister(struct inode inode, struct list_head head)
149b9a9d	330	{
3aed4dca FD	331	struct lttng_uprobe_handler iter, tmp;
	332
	333	/*
	334	* Iterate over the list of handler, remove each handler from the list
	335	* and free the struct.
	336	*/
9de67196 FD	337	list_for_each_entry_safe(iter, tmp, head, node) {
9de67196 FD	338	wrapper_uprobe_unregister(inode, iter->offset, &iter->up_consumer);
3aed4dca FD	339	list_del(&iter->node);
	340	kfree(iter);
	341	}
9de67196 FD	342
	343	}
	344
a67ba386	345	void lttng_uprobes_unregister_event(struct lttng_kernel_event_recorder *event_recorder)
9de67196	346	{
a67ba386	347	lttng_uprobes_unregister(event_recorder->priv->parent.u.uprobe.inode, &event_recorder->priv->parent.u.uprobe.head);
149b9a9d	348	}
83b802dc	349	EXPORT_SYMBOL_GPL(lttng_uprobes_unregister_event);
149b9a9d	350
a67ba386	351	void lttng_uprobes_unregister_event_notifier(struct lttng_kernel_event_notifier *event_notifier)
9de67196	352	{
a67ba386	353	lttng_uprobes_unregister(event_notifier->priv->parent.u.uprobe.inode, &event_notifier->priv->parent.u.uprobe.head);
9de67196 FD	354	}
	355	EXPORT_SYMBOL_GPL(lttng_uprobes_unregister_event_notifier);
	356
a67ba386	357	void lttng_uprobes_destroy_event_private(struct lttng_kernel_event_recorder *event_recorder)
149b9a9d	358	{
a67ba386 MD	359	iput(event_recorder->priv->parent.u.uprobe.inode);
	360	kfree(event_recorder->priv->parent.desc->fields[0]);
	361	kfree(event_recorder->priv->parent.desc->fields);
	362	kfree(event_recorder->priv->parent.desc->event_name);
	363	kfree(event_recorder->priv->parent.desc);
149b9a9d	364	}
83b802dc	365	EXPORT_SYMBOL_GPL(lttng_uprobes_destroy_event_private);
149b9a9d	366
a67ba386	367	void lttng_uprobes_destroy_event_notifier_private(struct lttng_kernel_event_notifier *event_notifier)
9de67196	368	{
a67ba386 MD	369	iput(event_notifier->priv->parent.u.uprobe.inode);
	370	kfree(event_notifier->priv->parent.desc->event_name);
	371	kfree(event_notifier->priv->parent.desc);
9de67196 FD	372	}
	373	EXPORT_SYMBOL_GPL(lttng_uprobes_destroy_event_notifier_private);
	374
149b9a9d YB	375	MODULE_LICENSE("GPL and additional rights");
	376	MODULE_AUTHOR("Yannick Brosseau");
	377	MODULE_DESCRIPTION("Linux Trace Toolkit Uprobes Support");