--- /dev/null
+/*
+ * ltt-debugfs-abi.c
+ *
+ * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * LTTng debugfs ABI
+ *
+ * Mimic system calls for:
+ * - session creation, returns a file descriptor or failure.
+ * - channel creation, returns a file descriptor or failure.
+ * - Operates on a session file descriptor
+ * - Takes all channel options as parameters.
+ * - stream get, returns a file descriptor or failure.
+ * - Operates on a channel file descriptor.
+ * - stream notifier get, returns a file descriptor or failure.
+ * - Operates on a channel file descriptor.
+ * - event creation, returns a file descriptor or failure.
+ * - Operates on a channel file descriptor
+ * - Takes an event name as parameter
+ * - Takes an instrumentation source as parameter
+ * - e.g. tracepoints, dynamic_probes...
+ * - Takes instrumentation source specific arguments.
+ *
+ * Dual LGPL v2.1/GPL v2 license.
+ */
+
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/proc_fs.h>
+#include <linux/anon_inodes.h>
+#include <linux/file.h>
+#include <linux/uaccess.h>
+#include <linux/slab.h>
+#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
+#include "wrapper/ringbuffer/vfs.h"
+#include "wrapper/poll.h"
+#include "ltt-debugfs-abi.h"
+#include "ltt-events.h"
+#include "ltt-tracer.h"
+
+/*
+ * This is LTTng's own personal way to create a system call as an external
+ * module. We use ioctl() on /sys/kernel/debug/lttng.
+ */
+
+static struct dentry *lttng_dentry;
+static struct proc_dir_entry *lttng_proc_dentry;
+static const struct file_operations lttng_fops;
+static const struct file_operations lttng_session_fops;
+static const struct file_operations lttng_channel_fops;
+static const struct file_operations lttng_metadata_fops;
+static const struct file_operations lttng_event_fops;
+
+/*
+ * Teardown management: opened file descriptors keep a refcount on the module,
+ * so it can only exit when all file descriptors are closed.
+ */
+
+enum channel_type {
+ PER_CPU_CHANNEL,
+ METADATA_CHANNEL,
+};
+
+static
+int lttng_abi_create_session(void)
+{
+ struct ltt_session *session;
+ struct file *session_file;
+ int session_fd, ret;
+
+ session = ltt_session_create();
+ if (!session)
+ return -ENOMEM;
+ session_fd = get_unused_fd();
+ if (session_fd < 0) {
+ ret = session_fd;
+ goto fd_error;
+ }
+ session_file = anon_inode_getfile("[lttng_session]",
+ <tng_session_fops,
+ session, O_RDWR);
+ if (IS_ERR(session_file)) {
+ ret = PTR_ERR(session_file);
+ goto file_error;
+ }
+ session->file = session_file;
+ fd_install(session_fd, session_file);
+ return session_fd;
+
+file_error:
+ put_unused_fd(session_fd);
+fd_error:
+ ltt_session_destroy(session);
+ return ret;
+}
+
+static
+int lttng_abi_tracepoint_list(void)
+{
+ struct file *tracepoint_list_file;
+ int file_fd, ret;
+
+ file_fd = get_unused_fd();
+ if (file_fd < 0) {
+ ret = file_fd;
+ goto fd_error;
+ }
+
+ tracepoint_list_file = anon_inode_getfile("[lttng_session]",
+ <tng_tracepoint_list_fops,
+ NULL, O_RDWR);
+ if (IS_ERR(tracepoint_list_file)) {
+ ret = PTR_ERR(tracepoint_list_file);
+ goto file_error;
+ }
+ ret = lttng_tracepoint_list_fops.open(NULL, tracepoint_list_file);
+ if (ret < 0)
+ goto open_error;
+ fd_install(file_fd, tracepoint_list_file);
+ if (file_fd < 0) {
+ ret = file_fd;
+ goto fd_error;
+ }
+ return file_fd;
+
+open_error:
+ fput(tracepoint_list_file);
+file_error:
+ put_unused_fd(file_fd);
+fd_error:
+ return ret;
+}
+
+static
+long lttng_abi_tracer_version(struct file *file,
+ struct lttng_kernel_tracer_version __user *uversion_param)
+{
+ struct lttng_kernel_tracer_version v;
+
+ v.version = LTTNG_VERSION;
+ v.patchlevel = LTTNG_PATCHLEVEL;
+ v.sublevel = LTTNG_SUBLEVEL;
+
+ if (copy_to_user(uversion_param, &v, sizeof(v)))
+ return -EFAULT;
+ return 0;
+}
+
+static
+long lttng_abi_add_context(struct file *file,
+ struct lttng_kernel_context __user *ucontext_param,
+ struct lttng_ctx **ctx, struct ltt_session *session)
+{
+ struct lttng_kernel_context context_param;
+
+ if (session->been_active)
+ return -EPERM;
+
+ if (copy_from_user(&context_param, ucontext_param, sizeof(context_param)))
+ return -EFAULT;
+
+ switch (context_param.ctx) {
+ case LTTNG_KERNEL_CONTEXT_PID:
+ return lttng_add_pid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_PRIO:
+ return lttng_add_prio_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_NICE:
+ return lttng_add_nice_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_VPID:
+ return lttng_add_vpid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_TID:
+ return lttng_add_tid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_VTID:
+ return lttng_add_vtid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_PPID:
+ return lttng_add_ppid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_VPPID:
+ return lttng_add_vppid_to_ctx(ctx);
+ case LTTNG_KERNEL_CONTEXT_PERF_COUNTER:
+ context_param.u.perf_counter.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ return lttng_add_perf_counter_to_ctx(context_param.u.perf_counter.type,
+ context_param.u.perf_counter.config,
+ context_param.u.perf_counter.name,
+ ctx);
+ case LTTNG_KERNEL_CONTEXT_PROCNAME:
+ return lttng_add_procname_to_ctx(ctx);
+ default:
+ return -EINVAL;
+ }
+}
+
+/**
+ * lttng_ioctl - lttng syscall through ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_SESSION
+ * Returns a LTTng trace session file descriptor
+ * LTTNG_KERNEL_TRACER_VERSION
+ * Returns the LTTng kernel tracer version
+ * LTTNG_KERNEL_TRACEPOINT_LIST
+ * Returns a file descriptor listing available tracepoints
+ * LTTNG_KERNEL_WAIT_QUIESCENT
+ * Returns after all previously running probes have completed
+ *
+ * The returned session will be deleted when its file descriptor is closed.
+ */
+static
+long lttng_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ case LTTNG_KERNEL_SESSION:
+ return lttng_abi_create_session();
+ case LTTNG_KERNEL_TRACER_VERSION:
+ return lttng_abi_tracer_version(file,
+ (struct lttng_kernel_tracer_version __user *) arg);
+ case LTTNG_KERNEL_TRACEPOINT_LIST:
+ return lttng_abi_tracepoint_list();
+ case LTTNG_KERNEL_WAIT_QUIESCENT:
+ synchronize_trace();
+ return 0;
+ case LTTNG_KERNEL_CALIBRATE:
+ {
+ struct lttng_kernel_calibrate __user *ucalibrate =
+ (struct lttng_kernel_calibrate __user *) arg;
+ struct lttng_kernel_calibrate calibrate;
+ int ret;
+
+ if (copy_from_user(&calibrate, ucalibrate, sizeof(calibrate)))
+ return -EFAULT;
+ ret = lttng_calibrate(&calibrate);
+ if (copy_to_user(ucalibrate, &calibrate, sizeof(calibrate)))
+ return -EFAULT;
+ return ret;
+ }
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static const struct file_operations lttng_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = lttng_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_ioctl,
+#endif
+};
+
+/*
+ * We tolerate no failure in this function (if one happens, we print a dmesg
+ * error, but cannot return any error, because the channel information is
+ * invariant.
+ */
+static
+void lttng_metadata_create_events(struct file *channel_file)
+{
+ struct ltt_channel *channel = channel_file->private_data;
+ static struct lttng_kernel_event metadata_params = {
+ .instrumentation = LTTNG_KERNEL_TRACEPOINT,
+ .name = "lttng_metadata",
+ };
+ struct ltt_event *event;
+
+ /*
+ * We tolerate no failure path after event creation. It will stay
+ * invariant for the rest of the session.
+ */
+ event = ltt_event_create(channel, &metadata_params, NULL, NULL);
+ if (!event) {
+ goto create_error;
+ }
+ return;
+
+create_error:
+ WARN_ON(1);
+ return; /* not allowed to return error */
+}
+
+static
+int lttng_abi_create_channel(struct file *session_file,
+ struct lttng_kernel_channel __user *uchan_param,
+ enum channel_type channel_type)
+{
+ struct ltt_session *session = session_file->private_data;
+ const struct file_operations *fops = NULL;
+ const char *transport_name;
+ struct ltt_channel *chan;
+ struct file *chan_file;
+ struct lttng_kernel_channel chan_param;
+ int chan_fd;
+ int ret = 0;
+
+ if (copy_from_user(&chan_param, uchan_param, sizeof(chan_param)))
+ return -EFAULT;
+ chan_fd = get_unused_fd();
+ if (chan_fd < 0) {
+ ret = chan_fd;
+ goto fd_error;
+ }
+ switch (channel_type) {
+ case PER_CPU_CHANNEL:
+ fops = <tng_channel_fops;
+ break;
+ case METADATA_CHANNEL:
+ fops = <tng_metadata_fops;
+ break;
+ }
+
+ chan_file = anon_inode_getfile("[lttng_channel]",
+ fops,
+ NULL, O_RDWR);
+ if (IS_ERR(chan_file)) {
+ ret = PTR_ERR(chan_file);
+ goto file_error;
+ }
+ switch (channel_type) {
+ case PER_CPU_CHANNEL:
+ if (chan_param.output == LTTNG_KERNEL_SPLICE) {
+ transport_name = chan_param.overwrite ?
+ "relay-overwrite" : "relay-discard";
+ } else if (chan_param.output == LTTNG_KERNEL_MMAP) {
+ transport_name = chan_param.overwrite ?
+ "relay-overwrite-mmap" : "relay-discard-mmap";
+ } else {
+ return -EINVAL;
+ }
+ break;
+ case METADATA_CHANNEL:
+ if (chan_param.output == LTTNG_KERNEL_SPLICE)
+ transport_name = "relay-metadata";
+ else if (chan_param.output == LTTNG_KERNEL_MMAP)
+ transport_name = "relay-metadata-mmap";
+ else
+ return -EINVAL;
+ break;
+ default:
+ transport_name = "<unknown>";
+ break;
+ }
+ /*
+ * We tolerate no failure path after channel creation. It will stay
+ * invariant for the rest of the session.
+ */
+ chan = ltt_channel_create(session, transport_name, NULL,
+ chan_param.subbuf_size,
+ chan_param.num_subbuf,
+ chan_param.switch_timer_interval,
+ chan_param.read_timer_interval);
+ if (!chan) {
+ ret = -EINVAL;
+ goto chan_error;
+ }
+ chan->file = chan_file;
+ chan_file->private_data = chan;
+ fd_install(chan_fd, chan_file);
+ if (channel_type == METADATA_CHANNEL) {
+ session->metadata = chan;
+ lttng_metadata_create_events(chan_file);
+ }
+
+ /* The channel created holds a reference on the session */
+ atomic_long_inc(&session_file->f_count);
+
+ return chan_fd;
+
+chan_error:
+ fput(chan_file);
+file_error:
+ put_unused_fd(chan_fd);
+fd_error:
+ return ret;
+}
+
+/**
+ * lttng_session_ioctl - lttng session fd ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_CHANNEL
+ * Returns a LTTng channel file descriptor
+ * LTTNG_KERNEL_ENABLE
+ * Enables tracing for a session (weak enable)
+ * LTTNG_KERNEL_DISABLE
+ * Disables tracing for a session (strong disable)
+ * LTTNG_KERNEL_METADATA
+ * Returns a LTTng metadata file descriptor
+ *
+ * The returned channel will be deleted when its file descriptor is closed.
+ */
+static
+long lttng_session_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct ltt_session *session = file->private_data;
+
+ switch (cmd) {
+ case LTTNG_KERNEL_CHANNEL:
+ return lttng_abi_create_channel(file,
+ (struct lttng_kernel_channel __user *) arg,
+ PER_CPU_CHANNEL);
+ case LTTNG_KERNEL_SESSION_START:
+ case LTTNG_KERNEL_ENABLE:
+ return ltt_session_enable(session);
+ case LTTNG_KERNEL_SESSION_STOP:
+ case LTTNG_KERNEL_DISABLE:
+ return ltt_session_disable(session);
+ case LTTNG_KERNEL_METADATA:
+ return lttng_abi_create_channel(file,
+ (struct lttng_kernel_channel __user *) arg,
+ METADATA_CHANNEL);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+/*
+ * Called when the last file reference is dropped.
+ *
+ * Big fat note: channels and events are invariant for the whole session after
+ * their creation. So this session destruction also destroys all channel and
+ * event structures specific to this session (they are not destroyed when their
+ * individual file is released).
+ */
+static
+int lttng_session_release(struct inode *inode, struct file *file)
+{
+ struct ltt_session *session = file->private_data;
+
+ if (session)
+ ltt_session_destroy(session);
+ return 0;
+}
+
+static const struct file_operations lttng_session_fops = {
+ .owner = THIS_MODULE,
+ .release = lttng_session_release,
+ .unlocked_ioctl = lttng_session_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_session_ioctl,
+#endif
+};
+
+static
+int lttng_abi_open_stream(struct file *channel_file)
+{
+ struct ltt_channel *channel = channel_file->private_data;
+ struct lib_ring_buffer *buf;
+ int stream_fd, ret;
+ struct file *stream_file;
+
+ buf = channel->ops->buffer_read_open(channel->chan);
+ if (!buf)
+ return -ENOENT;
+
+ stream_fd = get_unused_fd();
+ if (stream_fd < 0) {
+ ret = stream_fd;
+ goto fd_error;
+ }
+ stream_file = anon_inode_getfile("[lttng_stream]",
+ &lib_ring_buffer_file_operations,
+ buf, O_RDWR);
+ if (IS_ERR(stream_file)) {
+ ret = PTR_ERR(stream_file);
+ goto file_error;
+ }
+ /*
+ * OPEN_FMODE, called within anon_inode_getfile/alloc_file, don't honor
+ * FMODE_LSEEK, FMODE_PREAD nor FMODE_PWRITE. We need to read from this
+ * file descriptor, so we set FMODE_PREAD here.
+ */
+ stream_file->f_mode |= FMODE_PREAD;
+ fd_install(stream_fd, stream_file);
+ /*
+ * The stream holds a reference to the channel within the generic ring
+ * buffer library, so no need to hold a refcount on the channel and
+ * session files here.
+ */
+ return stream_fd;
+
+file_error:
+ put_unused_fd(stream_fd);
+fd_error:
+ channel->ops->buffer_read_close(buf);
+ return ret;
+}
+
+static
+int lttng_abi_create_event(struct file *channel_file,
+ struct lttng_kernel_event __user *uevent_param)
+{
+ struct ltt_channel *channel = channel_file->private_data;
+ struct ltt_event *event;
+ struct lttng_kernel_event event_param;
+ int event_fd, ret;
+ struct file *event_file;
+
+ if (copy_from_user(&event_param, uevent_param, sizeof(event_param)))
+ return -EFAULT;
+ event_param.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ switch (event_param.instrumentation) {
+ case LTTNG_KERNEL_KRETPROBE:
+ event_param.u.kretprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ break;
+ case LTTNG_KERNEL_KPROBE:
+ event_param.u.kprobe.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ break;
+ case LTTNG_KERNEL_FUNCTION:
+ event_param.u.ftrace.symbol_name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ break;
+ default:
+ break;
+ }
+ switch (event_param.instrumentation) {
+ default:
+ event_fd = get_unused_fd();
+ if (event_fd < 0) {
+ ret = event_fd;
+ goto fd_error;
+ }
+ event_file = anon_inode_getfile("[lttng_event]",
+ <tng_event_fops,
+ NULL, O_RDWR);
+ if (IS_ERR(event_file)) {
+ ret = PTR_ERR(event_file);
+ goto file_error;
+ }
+ /*
+ * We tolerate no failure path after event creation. It
+ * will stay invariant for the rest of the session.
+ */
+ event = ltt_event_create(channel, &event_param, NULL, NULL);
+ if (!event) {
+ ret = -EINVAL;
+ goto event_error;
+ }
+ event_file->private_data = event;
+ fd_install(event_fd, event_file);
+ /* The event holds a reference on the channel */
+ atomic_long_inc(&channel_file->f_count);
+ break;
+ case LTTNG_KERNEL_SYSCALL:
+ /*
+ * Only all-syscall tracing supported for now.
+ */
+ if (event_param.name[0] != '\0')
+ return -EINVAL;
+ ret = lttng_syscalls_register(channel, NULL);
+ if (ret)
+ goto fd_error;
+ event_fd = 0;
+ break;
+ }
+ return event_fd;
+
+event_error:
+ fput(event_file);
+file_error:
+ put_unused_fd(event_fd);
+fd_error:
+ return ret;
+}
+
+/**
+ * lttng_channel_ioctl - lttng syscall through ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_STREAM
+ * Returns an event stream file descriptor or failure.
+ * (typically, one event stream records events from one CPU)
+ * LTTNG_KERNEL_EVENT
+ * Returns an event file descriptor or failure.
+ * LTTNG_KERNEL_CONTEXT
+ * Prepend a context field to each event in the channel
+ * LTTNG_KERNEL_ENABLE
+ * Enable recording for events in this channel (weak enable)
+ * LTTNG_KERNEL_DISABLE
+ * Disable recording for events in this channel (strong disable)
+ *
+ * Channel and event file descriptors also hold a reference on the session.
+ */
+static
+long lttng_channel_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct ltt_channel *channel = file->private_data;
+
+ switch (cmd) {
+ case LTTNG_KERNEL_STREAM:
+ return lttng_abi_open_stream(file);
+ case LTTNG_KERNEL_EVENT:
+ return lttng_abi_create_event(file, (struct lttng_kernel_event __user *) arg);
+ case LTTNG_KERNEL_CONTEXT:
+ return lttng_abi_add_context(file,
+ (struct lttng_kernel_context __user *) arg,
+ &channel->ctx, channel->session);
+ case LTTNG_KERNEL_ENABLE:
+ return ltt_channel_enable(channel);
+ case LTTNG_KERNEL_DISABLE:
+ return ltt_channel_disable(channel);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+/**
+ * lttng_metadata_ioctl - lttng syscall through ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_STREAM
+ * Returns an event stream file descriptor or failure.
+ *
+ * Channel and event file descriptors also hold a reference on the session.
+ */
+static
+long lttng_metadata_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ case LTTNG_KERNEL_STREAM:
+ return lttng_abi_open_stream(file);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+/**
+ * lttng_channel_poll - lttng stream addition/removal monitoring
+ *
+ * @file: the file
+ * @wait: poll table
+ */
+unsigned int lttng_channel_poll(struct file *file, poll_table *wait)
+{
+ struct ltt_channel *channel = file->private_data;
+ unsigned int mask = 0;
+
+ if (file->f_mode & FMODE_READ) {
+ poll_wait_set_exclusive(wait);
+ poll_wait(file, channel->ops->get_hp_wait_queue(channel->chan),
+ wait);
+
+ if (channel->ops->is_disabled(channel->chan))
+ return POLLERR;
+ if (channel->ops->is_finalized(channel->chan))
+ return POLLHUP;
+ if (channel->ops->buffer_has_read_closed_stream(channel->chan))
+ return POLLIN | POLLRDNORM;
+ return 0;
+ }
+ return mask;
+
+}
+
+static
+int lttng_channel_release(struct inode *inode, struct file *file)
+{
+ struct ltt_channel *channel = file->private_data;
+
+ if (channel)
+ fput(channel->session->file);
+ return 0;
+}
+
+static const struct file_operations lttng_channel_fops = {
+ .owner = THIS_MODULE,
+ .release = lttng_channel_release,
+ .poll = lttng_channel_poll,
+ .unlocked_ioctl = lttng_channel_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_channel_ioctl,
+#endif
+};
+
+static const struct file_operations lttng_metadata_fops = {
+ .owner = THIS_MODULE,
+ .release = lttng_channel_release,
+ .unlocked_ioctl = lttng_metadata_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_metadata_ioctl,
+#endif
+};
+
+/**
+ * lttng_event_ioctl - lttng syscall through ioctl
+ *
+ * @file: the file
+ * @cmd: the command
+ * @arg: command arg
+ *
+ * This ioctl implements lttng commands:
+ * LTTNG_KERNEL_CONTEXT
+ * Prepend a context field to each record of this event
+ * LTTNG_KERNEL_ENABLE
+ * Enable recording for this event (weak enable)
+ * LTTNG_KERNEL_DISABLE
+ * Disable recording for this event (strong disable)
+ */
+static
+long lttng_event_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct ltt_event *event = file->private_data;
+
+ switch (cmd) {
+ case LTTNG_KERNEL_CONTEXT:
+ return lttng_abi_add_context(file,
+ (struct lttng_kernel_context __user *) arg,
+ &event->ctx, event->chan->session);
+ case LTTNG_KERNEL_ENABLE:
+ return ltt_event_enable(event);
+ case LTTNG_KERNEL_DISABLE:
+ return ltt_event_disable(event);
+ default:
+ return -ENOIOCTLCMD;
+ }
+}
+
+static
+int lttng_event_release(struct inode *inode, struct file *file)
+{
+ struct ltt_event *event = file->private_data;
+
+ if (event)
+ fput(event->chan->file);
+ return 0;
+}
+
+/* TODO: filter control ioctl */
+static const struct file_operations lttng_event_fops = {
+ .owner = THIS_MODULE,
+ .release = lttng_event_release,
+ .unlocked_ioctl = lttng_event_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = lttng_event_ioctl,
+#endif
+};
+
+int __init ltt_debugfs_abi_init(void)
+{
+ int ret = 0;
+
+ wrapper_vmalloc_sync_all();
+ lttng_dentry = debugfs_create_file("lttng", S_IWUSR, NULL, NULL,
+ <tng_fops);
+ if (IS_ERR(lttng_dentry))
+ lttng_dentry = NULL;
+
+ lttng_proc_dentry = proc_create_data("lttng", S_IWUSR, NULL,
+ <tng_fops, NULL);
+
+ if (!lttng_dentry && !lttng_proc_dentry) {
+ printk(KERN_ERR "Error creating LTTng control file\n");
+ ret = -ENOMEM;
+ goto error;
+ }
+error:
+ return ret;
+}
+
+void __exit ltt_debugfs_abi_exit(void)
+{
+ if (lttng_dentry)
+ debugfs_remove(lttng_dentry);
+ if (lttng_proc_dentry)
+ remove_proc_entry("lttng", NULL);
+}
--- /dev/null
+#ifndef _LTT_DEBUGFS_ABI_H
+#define _LTT_DEBUGFS_ABI_H
+
+/*
+ * ltt-debugfs-abi.h
+ *
+ * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * LTTng debugfs ABI header
+ *
+ * Dual LGPL v2.1/GPL v2 license.
+ */
+
+#include <linux/fs.h>
+
+#define LTTNG_SYM_NAME_LEN 128
+
+enum lttng_kernel_instrumentation {
+ LTTNG_KERNEL_TRACEPOINT = 0,
+ LTTNG_KERNEL_KPROBE = 1,
+ LTTNG_KERNEL_FUNCTION = 2,
+ LTTNG_KERNEL_KRETPROBE = 3,
+ LTTNG_KERNEL_NOOP = 4, /* not hooked */
+ LTTNG_KERNEL_SYSCALL = 5,
+};
+
+/*
+ * LTTng consumer mode
+ */
+enum lttng_kernel_output {
+ LTTNG_KERNEL_SPLICE = 0,
+ LTTNG_KERNEL_MMAP = 1,
+};
+
+/*
+ * LTTng DebugFS ABI structures.
+ */
+
+struct lttng_kernel_channel {
+ int overwrite; /* 1: overwrite, 0: discard */
+ uint64_t subbuf_size; /* in bytes */
+ uint64_t num_subbuf;
+ unsigned int switch_timer_interval; /* usecs */
+ unsigned int read_timer_interval; /* usecs */
+ enum lttng_kernel_output output; /* splice, mmap */
+};
+
+struct lttng_kernel_kretprobe {
+ uint64_t addr;
+
+ uint64_t offset;
+ char symbol_name[LTTNG_SYM_NAME_LEN];
+};
+
+/*
+ * Either addr is used, or symbol_name and offset.
+ */
+struct lttng_kernel_kprobe {
+ uint64_t addr;
+
+ uint64_t offset;
+ char symbol_name[LTTNG_SYM_NAME_LEN];
+};
+
+struct lttng_kernel_function_tracer {
+ char symbol_name[LTTNG_SYM_NAME_LEN];
+};
+
+/*
+ * For syscall tracing, name = '\0' means "enable all".
+ */
+struct lttng_kernel_event {
+ char name[LTTNG_SYM_NAME_LEN]; /* event name */
+ enum lttng_kernel_instrumentation instrumentation;
+ /* Per instrumentation type configuration */
+ union {
+ struct lttng_kernel_kretprobe kretprobe;
+ struct lttng_kernel_kprobe kprobe;
+ struct lttng_kernel_function_tracer ftrace;
+ } u;
+};
+
+struct lttng_kernel_tracer_version {
+ uint32_t version;
+ uint32_t patchlevel;
+ uint32_t sublevel;
+};
+
+enum lttng_kernel_calibrate_type {
+ LTTNG_KERNEL_CALIBRATE_KRETPROBE,
+};
+
+struct lttng_kernel_calibrate {
+ enum lttng_kernel_calibrate_type type; /* type (input) */
+};
+
+enum lttng_kernel_context_type {
+ LTTNG_KERNEL_CONTEXT_PID = 0,
+ LTTNG_KERNEL_CONTEXT_PERF_COUNTER = 1,
+ LTTNG_KERNEL_CONTEXT_PROCNAME = 2,
+ LTTNG_KERNEL_CONTEXT_PRIO = 3,
+ LTTNG_KERNEL_CONTEXT_NICE = 4,
+ LTTNG_KERNEL_CONTEXT_VPID = 5,
+ LTTNG_KERNEL_CONTEXT_TID = 6,
+ LTTNG_KERNEL_CONTEXT_VTID = 7,
+ LTTNG_KERNEL_CONTEXT_PPID = 8,
+ LTTNG_KERNEL_CONTEXT_VPPID = 9,
+};
+
+struct lttng_kernel_perf_counter_ctx {
+ uint32_t type;
+ uint64_t config;
+ char name[LTTNG_SYM_NAME_LEN];
+};
+
+struct lttng_kernel_context {
+ enum lttng_kernel_context_type ctx;
+ union {
+ struct lttng_kernel_perf_counter_ctx perf_counter;
+ } u;
+};
+
+/* LTTng file descriptor ioctl */
+#define LTTNG_KERNEL_SESSION _IO(0xF6, 0x40)
+#define LTTNG_KERNEL_TRACER_VERSION \
+ _IOR(0xF6, 0x41, struct lttng_kernel_tracer_version)
+#define LTTNG_KERNEL_TRACEPOINT_LIST _IO(0xF6, 0x42)
+#define LTTNG_KERNEL_WAIT_QUIESCENT _IO(0xF6, 0x43)
+#define LTTNG_KERNEL_CALIBRATE \
+ _IOWR(0xF6, 0x44, struct lttng_kernel_calibrate)
+
+/* Session FD ioctl */
+#define LTTNG_KERNEL_METADATA \
+ _IOW(0xF6, 0x50, struct lttng_kernel_channel)
+#define LTTNG_KERNEL_CHANNEL \
+ _IOW(0xF6, 0x51, struct lttng_kernel_channel)
+#define LTTNG_KERNEL_SESSION_START _IO(0xF6, 0x52)
+#define LTTNG_KERNEL_SESSION_STOP _IO(0xF6, 0x53)
+
+/* Channel FD ioctl */
+#define LTTNG_KERNEL_STREAM _IO(0xF6, 0x60)
+#define LTTNG_KERNEL_EVENT \
+ _IOW(0xF6, 0x61, struct lttng_kernel_event)
+
+/* Event and Channel FD ioctl */
+#define LTTNG_KERNEL_CONTEXT \
+ _IOW(0xF6, 0x70, struct lttng_kernel_context)
+
+/* Event, Channel and Session ioctl */
+#define LTTNG_KERNEL_ENABLE _IO(0xF6, 0x80)
+#define LTTNG_KERNEL_DISABLE _IO(0xF6, 0x81)
+
+#endif /* _LTT_DEBUGFS_ABI_H */