/*
* lttng-syscalls.c
*
- * Copyright 2010 (c) - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ * LTTng syscall probes.
*
- * LTTng sched probes.
+ * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
- * Dual LGPL v2.1/GPL v2 license.
+ * 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/slab.h>
+#include <linux/compat.h>
+#include <linux/err.h>
#include <asm/ptrace.h>
#include <asm/syscall.h>
-#include "ltt-events.h"
+#include "wrapper/tracepoint.h"
+#include "lttng-events.h"
+
+#ifndef CONFIG_COMPAT
+# ifndef is_compat_task
+# define is_compat_task() (0)
+# endif
+#endif
-static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id);
+static
+void syscall_entry_probe(void *__data, struct pt_regs *regs, long id);
+
+/*
+ * Forward declarations for old kernels.
+ */
+struct mmsghdr;
+struct rlimit64;
+struct oldold_utsname;
+struct old_utsname;
+struct sel_arg_struct;
+struct mmap_arg_struct;
/*
* Take care of NOARGS not supported by mainline.
*/
#define LTTNG_PACKAGE_BUILD
#define CREATE_TRACE_POINTS
+#define TP_MODULE_NOINIT
+#define TRACE_INCLUDE_PATH ../instrumentation/syscalls/headers
+
+#define PARAMS(args...) args
/* Hijack probe callback for system calls */
+#undef TP_PROBE_CB
#define TP_PROBE_CB(_template) &syscall_entry_probe
-#define TP_MODULE_OVERRIDE
-
-#define TRACE_INCLUDE_PATH ../instrumentation/syscalls/headers
+#define SC_TRACE_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+ TRACE_EVENT(_name, PARAMS(_proto), PARAMS(_args),\
+ PARAMS(_struct), PARAMS(_assign), PARAMS(_printk))
+#define SC_DECLARE_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
+ DECLARE_EVENT_CLASS_NOARGS(_name, PARAMS(_struct), PARAMS(_assign),\
+ PARAMS(_printk))
+#define SC_DEFINE_EVENT_NOARGS(_template, _name) \
+ DEFINE_EVENT_NOARGS(_template, _name)
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM syscalls_integers
+#include "instrumentation/syscalls/headers/syscalls_integers.h"
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM syscalls_pointers
+#include "instrumentation/syscalls/headers/syscalls_pointers.h"
+#undef TRACE_SYSTEM
+#undef SC_TRACE_EVENT
+#undef SC_DECLARE_EVENT_CLASS_NOARGS
+#undef SC_DEFINE_EVENT_NOARGS
+
+#define TRACE_SYSTEM syscalls_unknown
+#include "instrumentation/syscalls/headers/syscalls_unknown.h"
+#undef TRACE_SYSTEM
+
+/* For compat syscalls */
+#undef _TRACE_SYSCALLS_integers_H
+#undef _TRACE_SYSCALLS_pointers_H
-#include "instrumentation/syscalls/headers/syscalls.h"
-
-#undef TP_MODULE_OVERRIDE
+/* Hijack probe callback for system calls */
+#undef TP_PROBE_CB
+#define TP_PROBE_CB(_template) &syscall_entry_probe
+#define SC_TRACE_EVENT(_name, _proto, _args, _struct, _assign, _printk) \
+ TRACE_EVENT(compat_##_name, PARAMS(_proto), PARAMS(_args), \
+ PARAMS(_struct), PARAMS(_assign), \
+ PARAMS(_printk))
+#define SC_DECLARE_EVENT_CLASS_NOARGS(_name, _struct, _assign, _printk) \
+ DECLARE_EVENT_CLASS_NOARGS(compat_##_name, PARAMS(_struct), \
+ PARAMS(_assign), PARAMS(_printk))
+#define SC_DEFINE_EVENT_NOARGS(_template, _name) \
+ DEFINE_EVENT_NOARGS(compat_##_template, compat_##_name)
+#define TRACE_SYSTEM compat_syscalls_integers
+#include "instrumentation/syscalls/headers/compat_syscalls_integers.h"
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM compat_syscalls_pointers
+#include "instrumentation/syscalls/headers/compat_syscalls_pointers.h"
+#undef TRACE_SYSTEM
+#undef SC_TRACE_EVENT
+#undef SC_DECLARE_EVENT_CLASS_NOARGS
+#undef SC_DEFINE_EVENT_NOARGS
#undef TP_PROBE_CB
+
+#undef TP_MODULE_NOINIT
#undef LTTNG_PACKAGE_BUILD
#undef CREATE_TRACE_POINTS
unsigned int nrargs;
};
-static int sc_table_desc_filled;
-
#define CREATE_SYSCALL_TABLE
#undef TRACE_SYSCALL_TABLE
.desc = &__event_desc___##_name, \
},
-static struct trace_syscall_entry sc_table[] = {
-#include "instrumentation/syscalls/headers/syscalls.h"
+static const struct trace_syscall_entry sc_table[] = {
+#include "instrumentation/syscalls/headers/syscalls_integers.h"
+#include "instrumentation/syscalls/headers/syscalls_pointers.h"
+};
+
+#undef TRACE_SYSCALL_TABLE
+#define TRACE_SYSCALL_TABLE(_template, _name, _nr, _nrargs) \
+ [ _nr ] = { \
+ .func = __event_probe__##compat_##_template, \
+ .nrargs = (_nrargs), \
+ .fields = __event_fields___##compat_##_template,\
+ .desc = &__event_desc___##compat_##_name, \
+ },
+
+/* Create compatibility syscall table */
+const struct trace_syscall_entry compat_sc_table[] = {
+#include "instrumentation/syscalls/headers/compat_syscalls_integers.h"
+#include "instrumentation/syscalls/headers/compat_syscalls_pointers.h"
};
#undef CREATE_SYSCALL_TABLE
-static void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
+static void syscall_entry_unknown(struct lttng_event *event,
+ struct pt_regs *regs, unsigned int id)
{
- struct trace_syscall_entry *entry;
- struct ltt_channel *chan = __data;
- struct ltt_event *event;
+ unsigned long args[UNKNOWN_SYSCALL_NRARGS];
- if (unlikely(id >= ARRAY_SIZE(sc_table)))
+ syscall_get_arguments(current, regs, 0, UNKNOWN_SYSCALL_NRARGS, args);
+ if (unlikely(is_compat_task()))
+ __event_probe__compat_sys_unknown(event, id, args);
+ else
+ __event_probe__sys_unknown(event, id, args);
+}
+
+void syscall_entry_probe(void *__data, struct pt_regs *regs, long id)
+{
+ struct lttng_channel *chan = __data;
+ struct lttng_event *event, *unknown_event;
+ const struct trace_syscall_entry *table, *entry;
+ size_t table_len;
+
+ if (unlikely(is_compat_task())) {
+ table = compat_sc_table;
+ table_len = ARRAY_SIZE(compat_sc_table);
+ unknown_event = chan->sc_compat_unknown;
+ } else {
+ table = sc_table;
+ table_len = ARRAY_SIZE(sc_table);
+ unknown_event = chan->sc_unknown;
+ }
+ if (unlikely(id >= table_len)) {
+ syscall_entry_unknown(unknown_event, regs, id);
return;
- entry = &sc_table[id];
- if (unlikely(!entry->func))
+ }
+ if (unlikely(is_compat_task()))
+ event = chan->compat_sc_table[id];
+ else
+ event = chan->sc_table[id];
+ if (unlikely(!event)) {
+ syscall_entry_unknown(unknown_event, regs, id);
return;
- event = chan->sc_table[id];
- WARN_ON_ONCE(!event);
+ }
+ entry = &table[id];
+ WARN_ON_ONCE(!entry);
switch (entry->nrargs) {
case 0:
}
}
-int lttng_syscalls_register(struct ltt_channel *chan, void *filter)
+/* noinline to diminish caller stack size */
+static
+int fill_table(const struct trace_syscall_entry *table, size_t table_len,
+ struct lttng_event **chan_table, struct lttng_channel *chan, void *filter)
{
+ const struct lttng_event_desc *desc;
unsigned int i;
- int ret;
-
- wrapper_vmalloc_sync_all();
-
- if (!chan->sc_table) {
- /* create syscall table mapping syscall to events */
- chan->sc_table = kzalloc(sizeof(struct ltt_event *)
- * ARRAY_SIZE(sc_table), GFP_KERNEL);
- if (!chan->sc_table)
- return -ENOMEM;
- }
/* Allocate events for each syscall, insert into table */
- for (i = 0; i < ARRAY_SIZE(sc_table); i++) {
+ for (i = 0; i < table_len; i++) {
struct lttng_kernel_event ev;
- const struct lttng_event_desc *desc = sc_table[i].desc;
+ desc = table[i].desc;
- if (!desc)
+ if (!desc) {
+ /* Unknown syscall */
continue;
+ }
/*
* Skip those already populated by previous failed
* register for this channel.
*/
- if (chan->sc_table[i])
+ if (chan_table[i])
continue;
memset(&ev, 0, sizeof(ev));
- strncpy(ev.name, desc->name, LTTNG_SYM_NAME_LEN);
- ev.name[LTTNG_SYM_NAME_LEN - 1] = '\0';
+ strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
+ ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
ev.instrumentation = LTTNG_KERNEL_NOOP;
- chan->sc_table[i] = ltt_event_create(chan, &ev, filter,
- desc);
- if (!chan->sc_table[i]) {
+ chan_table[i] = lttng_event_create(chan, &ev, filter,
+ desc);
+ WARN_ON_ONCE(!chan_table[i]);
+ if (IS_ERR(chan_table[i])) {
/*
* If something goes wrong in event registration
* after the first one, we have no choice but to
* leave the previous events in there, until
* deleted by session teardown.
*/
- return -EINVAL;
+ return PTR_ERR(chan_table[i]);
}
}
- ret = tracepoint_probe_register("sys_enter",
+ return 0;
+}
+
+int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
+{
+ struct lttng_kernel_event ev;
+ int ret;
+
+ wrapper_vmalloc_sync_all();
+
+ if (!chan->sc_table) {
+ /* create syscall table mapping syscall to events */
+ chan->sc_table = kzalloc(sizeof(struct lttng_event *)
+ * ARRAY_SIZE(sc_table), GFP_KERNEL);
+ if (!chan->sc_table)
+ return -ENOMEM;
+ }
+
+#ifdef CONFIG_COMPAT
+ if (!chan->compat_sc_table) {
+ /* create syscall table mapping compat syscall to events */
+ chan->compat_sc_table = kzalloc(sizeof(struct lttng_event *)
+ * ARRAY_SIZE(compat_sc_table), GFP_KERNEL);
+ if (!chan->compat_sc_table)
+ return -ENOMEM;
+ }
+#endif
+ if (!chan->sc_unknown) {
+ const struct lttng_event_desc *desc =
+ &__event_desc___sys_unknown;
+
+ memset(&ev, 0, sizeof(ev));
+ strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
+ ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+ ev.instrumentation = LTTNG_KERNEL_NOOP;
+ chan->sc_unknown = lttng_event_create(chan, &ev, filter,
+ desc);
+ WARN_ON_ONCE(!chan->sc_unknown);
+ if (IS_ERR(chan->sc_unknown)) {
+ return PTR_ERR(chan->sc_unknown);
+ }
+ }
+
+ if (!chan->sc_compat_unknown) {
+ const struct lttng_event_desc *desc =
+ &__event_desc___compat_sys_unknown;
+
+ memset(&ev, 0, sizeof(ev));
+ strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
+ ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+ ev.instrumentation = LTTNG_KERNEL_NOOP;
+ chan->sc_compat_unknown = lttng_event_create(chan, &ev, filter,
+ desc);
+ WARN_ON_ONCE(!chan->sc_unknown);
+ if (IS_ERR(chan->sc_compat_unknown)) {
+ return PTR_ERR(chan->sc_compat_unknown);
+ }
+ }
+
+ if (!chan->sc_exit) {
+ const struct lttng_event_desc *desc =
+ &__event_desc___exit_syscall;
+
+ memset(&ev, 0, sizeof(ev));
+ strncpy(ev.name, desc->name, LTTNG_KERNEL_SYM_NAME_LEN);
+ ev.name[LTTNG_KERNEL_SYM_NAME_LEN - 1] = '\0';
+ ev.instrumentation = LTTNG_KERNEL_NOOP;
+ chan->sc_exit = lttng_event_create(chan, &ev, filter,
+ desc);
+ WARN_ON_ONCE(!chan->sc_exit);
+ if (IS_ERR(chan->sc_exit)) {
+ return PTR_ERR(chan->sc_exit);
+ }
+ }
+
+ ret = fill_table(sc_table, ARRAY_SIZE(sc_table),
+ chan->sc_table, chan, filter);
+ if (ret)
+ return ret;
+#ifdef CONFIG_COMPAT
+ ret = fill_table(compat_sc_table, ARRAY_SIZE(compat_sc_table),
+ chan->compat_sc_table, chan, filter);
+ if (ret)
+ return ret;
+#endif
+ ret = lttng_wrapper_tracepoint_probe_register("sys_enter",
(void *) syscall_entry_probe, chan);
+ if (ret)
+ return ret;
+ /*
+ * We change the name of sys_exit tracepoint due to namespace
+ * conflict with sys_exit syscall entry.
+ */
+ ret = lttng_wrapper_tracepoint_probe_register("sys_exit",
+ (void *) __event_probe__exit_syscall,
+ chan->sc_exit);
+ if (ret) {
+ WARN_ON_ONCE(lttng_wrapper_tracepoint_probe_unregister("sys_enter",
+ (void *) syscall_entry_probe, chan));
+ }
return ret;
}
/*
* Only called at session destruction.
*/
-int lttng_syscalls_unregister(struct ltt_channel *chan)
+int lttng_syscalls_unregister(struct lttng_channel *chan)
{
int ret;
if (!chan->sc_table)
return 0;
- ret = tracepoint_probe_unregister("sys_enter",
+ ret = lttng_wrapper_tracepoint_probe_unregister("sys_exit",
+ (void *) __event_probe__exit_syscall,
+ chan->sc_exit);
+ if (ret)
+ return ret;
+ ret = lttng_wrapper_tracepoint_probe_unregister("sys_enter",
(void *) syscall_entry_probe, chan);
if (ret)
return ret;
- /* ltt_event destroy will be performed by ltt_session_destroy() */
+ /* lttng_event destroy will be performed by lttng_session_destroy() */
kfree(chan->sc_table);
+#ifdef CONFIG_COMPAT
+ kfree(chan->compat_sc_table);
+#endif
return 0;
}