/*-
* Copyright (c) 2017 Hans Petter Selasky
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice unmodified, this list of conditions, and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <linux/compat.h>
#include <linux/mm.h>
#include <linux/kthread.h>
#include <sys/kernel.h>
#include <sys/eventhandler.h>
#include <sys/malloc.h>
static eventhandler_tag linuxkpi_thread_dtor_tag;
static MALLOC_DEFINE(M_LINUX_CURRENT, "linuxcurrent", "LinuxKPI task structure");
int
linux_alloc_current(struct thread *td, int flags)
{
struct task_struct *ts;
struct mm_struct *mm;
MPASS(td->td_lkpi_task == NULL);
ts = malloc(sizeof(*ts), M_LINUX_CURRENT, flags | M_ZERO);
if (ts == NULL)
return (ENOMEM);
mm = malloc(sizeof(*mm), M_LINUX_CURRENT, flags | M_ZERO);
if (mm == NULL) {
free(ts, M_LINUX_CURRENT);
return (ENOMEM);
}
atomic_set(&ts->kthread_flags, 0);
ts->task_thread = td;
ts->comm = td->td_name;
ts->pid = td->td_tid;
ts->mm = mm;
atomic_set(&ts->usage, 1);
ts->state = TASK_RUNNING;
/* setup mm_struct */
init_rwsem(&mm->mmap_sem);
atomic_set(&mm->mm_count, 1);
atomic_set(&mm->mm_users, 1);
mm->vmspace = vmspace_acquire_ref(td->td_proc);
/* store pointer to task struct */
td->td_lkpi_task = ts;
return (0);
}
struct mm_struct *
linux_get_task_mm(struct task_struct *task)
{
struct mm_struct *mm;
mm = task->mm;
if (mm != NULL && mm->vmspace != NULL) {
atomic_inc(&mm->mm_users);
return (mm);
}
return (NULL);
}
void
linux_mm_dtor(struct mm_struct *mm)
{
if (mm->vmspace != NULL)
vmspace_free(mm->vmspace);
free(mm, M_LINUX_CURRENT);
}
void
linux_free_current(struct task_struct *ts)
{
mmput(ts->mm);
free(ts, M_LINUX_CURRENT);
}
static void
linuxkpi_thread_dtor(void *arg __unused, struct thread *td)
{
struct task_struct *ts;
ts = td->td_lkpi_task;
if (ts == NULL)
return;
td->td_lkpi_task = NULL;
put_task_struct(ts);
}
struct task_struct *
linux_pid_task(pid_t pid)
{
struct thread *td;
td = tdfind(pid, -1);
if (td != NULL) {
struct task_struct *ts = td->td_lkpi_task;
PROC_UNLOCK(td->td_proc);
return (ts);
}
return (NULL);
}
struct task_struct *
linux_get_pid_task(pid_t pid)
{
struct thread *td;
td = tdfind(pid, -1);
if (td != NULL) {
struct task_struct *ts = td->td_lkpi_task;
if (ts != NULL)
get_task_struct(ts);
PROC_UNLOCK(td->td_proc);
return (ts);
}
return (NULL);
}
static void
linux_current_init(void *arg __unused)
{
linuxkpi_thread_dtor_tag = EVENTHANDLER_REGISTER(thread_dtor,
linuxkpi_thread_dtor, NULL, EVENTHANDLER_PRI_ANY);
}
SYSINIT(linux_current, SI_SUB_EVENTHANDLER, SI_ORDER_SECOND, linux_current_init, NULL);
static void
linux_current_uninit(void *arg __unused)
{
EVENTHANDLER_DEREGISTER(thread_dtor, linuxkpi_thread_dtor_tag);
}
SYSUNINIT(linux_current, SI_SUB_EVENTHANDLER, SI_ORDER_SECOND, linux_current_uninit, NULL);