Move linux_clone(), linux_fork(), linux_vfork() to a MI path.

1 files changed, 297 insertions, 0 deletions

diff --git a/sys/compat/linux/linux_fork.c b/sys/compat/linux/linux_fork.c
new file mode 100644
index 0000000..b79fd35
--- /dev/null
+++ b/sys/compat/linux/linux_fork.c
@@ -0,0 +1,297 @@
+/*-
+ * Copyright (c) 2004 Tim J. Robbins
+ * Copyright (c) 2002 Doug Rabson
+ * Copyright (c) 2000 Marcel Moolenaar
+ * 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, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 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 "opt_compat.h"
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/imgact.h>
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/sched.h>
+#include <sys/sx.h>
+#include <sys/unistd.h>
+
+#include <machine/frame.h>
+
+#ifdef COMPAT_LINUX32
+#include <machine/../linux32/linux.h>
+#include <machine/../linux32/linux32_proto.h>
+#else
+#include <machine/../linux/linux.h>
+#include <machine/../linux/linux_proto.h>
+#endif
+#include <compat/linux/linux_signal.h>
+#include <compat/linux/linux_emul.h>
+
+
+int
+linux_fork(struct thread *td, struct linux_fork_args *args)
+{
+	int error;
+	struct proc *p2;
+	struct thread *td2;
+
+#ifdef DEBUG
+	if (ldebug(fork))
+		printf(ARGS(fork, ""));
+#endif
+
+	if ((error = fork1(td, RFFDG | RFPROC | RFSTOPPED, 0, &p2)) != 0)
+		return (error);
+
+	if (error == 0) {
+		td->td_retval[0] = p2->p_pid;
+		td->td_retval[1] = 0;
+	}
+
+	if (td->td_retval[1] == 1)
+		td->td_retval[0] = 0;
+	error = linux_proc_init(td, td->td_retval[0], 0);
+	if (error)
+		return (error);
+
+	td2 = FIRST_THREAD_IN_PROC(p2);
+
+	/*
+	 * Make this runnable after we are finished with it.
+	 */
+	thread_lock(td2);
+	TD_SET_CAN_RUN(td2);
+	sched_add(td2, SRQ_BORING);
+	thread_unlock(td2);
+
+	return (0);
+}
+
+int
+linux_vfork(struct thread *td, struct linux_vfork_args *args)
+{
+	int error;
+	struct proc *p2;
+	struct thread *td2;
+
+#ifdef DEBUG
+	if (ldebug(vfork))
+		printf(ARGS(vfork, ""));
+#endif
+
+	/* Exclude RFPPWAIT */
+	if ((error = fork1(td, RFFDG | RFPROC | RFMEM | RFSTOPPED, 0, &p2)) != 0)
+		return (error);
+	if (error == 0) {
+	   	td->td_retval[0] = p2->p_pid;
+		td->td_retval[1] = 0;
+	}
+	/* Are we the child? */
+	if (td->td_retval[1] == 1)
+		td->td_retval[0] = 0;
+	error = linux_proc_init(td, td->td_retval[0], 0);
+	if (error)
+		return (error);
+
+	PROC_LOCK(p2);
+	p2->p_flag |= P_PPWAIT;
+	PROC_UNLOCK(p2);
+
+	td2 = FIRST_THREAD_IN_PROC(p2);
+
+	/*
+	 * Make this runnable after we are finished with it.
+	 */
+	thread_lock(td2);
+	TD_SET_CAN_RUN(td2);
+	sched_add(td2, SRQ_BORING);
+	thread_unlock(td2);
+
+	/* wait for the children to exit, ie. emulate vfork */
+	PROC_LOCK(p2);
+	while (p2->p_flag & P_PPWAIT)
+		cv_wait(&p2->p_pwait, &p2->p_mtx);
+	PROC_UNLOCK(p2);
+
+	return (0);
+}
+
+int
+linux_clone(struct thread *td, struct linux_clone_args *args)
+{
+	int error, ff = RFPROC | RFSTOPPED;
+	struct proc *p2;
+	struct thread *td2;
+	int exit_signal;
+	struct linux_emuldata *em;
+
+#ifdef DEBUG
+	if (ldebug(clone)) {
+		printf(ARGS(clone, "flags %x, stack %p, parent tid: %p, "
+		    "child tid: %p"), (unsigned)args->flags,
+		    args->stack, args->parent_tidptr, args->child_tidptr);
+	}
+#endif
+
+	exit_signal = args->flags & 0x000000ff;
+	if (LINUX_SIG_VALID(exit_signal)) {
+		if (exit_signal <= LINUX_SIGTBLSZ)
+			exit_signal =
+			    linux_to_bsd_signal[_SIG_IDX(exit_signal)];
+	} else if (exit_signal != 0)
+		return (EINVAL);
+
+	if (args->flags & LINUX_CLONE_VM)
+		ff |= RFMEM;
+	if (args->flags & LINUX_CLONE_SIGHAND)
+		ff |= RFSIGSHARE;
+	/*
+	 * XXX: In Linux, sharing of fs info (chroot/cwd/umask)
+	 * and open files is independant.  In FreeBSD, its in one
+	 * structure but in reality it does not cause any problems
+	 * because both of these flags are usually set together.
+	 */
+	if (!(args->flags & (LINUX_CLONE_FILES | LINUX_CLONE_FS)))
+		ff |= RFFDG;
+
+	/*
+	 * Attempt to detect when linux_clone(2) is used for creating
+	 * kernel threads. Unfortunately despite the existence of the
+	 * CLONE_THREAD flag, version of linuxthreads package used in
+	 * most popular distros as of beginning of 2005 doesn't make
+	 * any use of it. Therefore, this detection relies on
+	 * empirical observation that linuxthreads sets certain
+	 * combination of flags, so that we can make more or less
+	 * precise detection and notify the FreeBSD kernel that several
+	 * processes are in fact part of the same threading group, so
+	 * that special treatment is necessary for signal delivery
+	 * between those processes and fd locking.
+	 */
+	if ((args->flags & 0xffffff00) == LINUX_THREADING_FLAGS)
+		ff |= RFTHREAD;
+
+	if (args->flags & LINUX_CLONE_PARENT_SETTID)
+		if (args->parent_tidptr == NULL)
+			return (EINVAL);
+
+	error = fork1(td, ff, 0, &p2);
+	if (error)
+		return (error);
+
+	if (args->flags & (LINUX_CLONE_PARENT | LINUX_CLONE_THREAD)) {
+	   	sx_xlock(&proctree_lock);
+		PROC_LOCK(p2);
+		proc_reparent(p2, td->td_proc->p_pptr);
+		PROC_UNLOCK(p2);
+		sx_xunlock(&proctree_lock);
+	}
+
+	/* create the emuldata */
+	error = linux_proc_init(td, p2->p_pid, args->flags);
+	/* reference it - no need to check this */
+	em = em_find(p2, EMUL_DOLOCK);
+	KASSERT(em != NULL, ("clone: emuldata not found."));
+	/* and adjust it */
+
+	if (args->flags & LINUX_CLONE_THREAD) {
+#ifdef notyet
+	   	PROC_LOCK(p2);
+	   	p2->p_pgrp = td->td_proc->p_pgrp;
+	   	PROC_UNLOCK(p2);
+#endif
+		exit_signal = 0;
+	}
+
+	if (args->flags & LINUX_CLONE_CHILD_SETTID)
+		em->child_set_tid = args->child_tidptr;
+	else
+	   	em->child_set_tid = NULL;
+
+	if (args->flags & LINUX_CLONE_CHILD_CLEARTID)
+		em->child_clear_tid = args->child_tidptr;
+	else
+	   	em->child_clear_tid = NULL;
+
+	EMUL_UNLOCK(&emul_lock);
+
+	if (args->flags & LINUX_CLONE_PARENT_SETTID) {
+		error = copyout(&p2->p_pid, args->parent_tidptr,
+		    sizeof(p2->p_pid));
+		if (error)
+			printf(LMSG("copyout failed!"));
+	}
+
+	PROC_LOCK(p2);
+	p2->p_sigparent = exit_signal;
+	PROC_UNLOCK(p2);
+	td2 = FIRST_THREAD_IN_PROC(p2);
+	/*
+	 * In a case of stack = NULL, we are supposed to COW calling process
+	 * stack. This is what normal fork() does, so we just keep tf_rsp arg
+	 * intact.
+	 */
+	if (args->stack)
+		linux_set_upcall_kse(td2, PTROUT(args->stack));
+
+	if (args->flags & LINUX_CLONE_SETTLS)
+		linux_set_cloned_tls(td2, args->tls);
+
+#ifdef DEBUG
+	if (ldebug(clone))
+		printf(LMSG("clone: successful rfork to %d, "
+		    "stack %p sig = %d"), (int)p2->p_pid, args->stack,
+		    exit_signal);
+#endif
+	if (args->flags & LINUX_CLONE_VFORK) {
+	   	PROC_LOCK(p2);
+	   	p2->p_flag |= P_PPWAIT;
+	   	PROC_UNLOCK(p2);
+	}
+
+	/*
+	 * Make this runnable after we are finished with it.
+	 */
+	thread_lock(td2);
+	TD_SET_CAN_RUN(td2);
+	sched_add(td2, SRQ_BORING);
+	thread_unlock(td2);
+
+	td->td_retval[0] = p2->p_pid;
+	td->td_retval[1] = 0;
+
+	if (args->flags & LINUX_CLONE_VFORK) {
+		/* wait for the children to exit, ie. emulate vfork */
+		PROC_LOCK(p2);
+		while (p2->p_flag & P_PPWAIT)
+			cv_wait(&p2->p_pwait, &p2->p_mtx);
+		PROC_UNLOCK(p2);
+	}
+
+	return (0);
+}