cobalt/syscall: pipeline: abstract syscall entry points

The I-pipe and Dovetail differ only marginally with respect to syscall
handling. Abstract only the few details we need to cope with both
interfaces.

No functional change is introduced.
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

include/cobalt/kernel/ipipe/pipeline/kevents.h

@@ -7,6 +7,9 @@
 #ifndef _COBALT_KERNEL_IPIPE_KEVENTS_H
 #define _COBALT_KERNEL_IPIPE_KEVENTS_H
 
+#define KEVENT_PROPAGATE   0
+#define KEVENT_STOP        1
+
 struct cobalt_process;
 struct cobalt_thread;
 

include/cobalt/kernel/ipipe/pipeline/pipeline.h

@@ -11,6 +11,8 @@
 
 #include <pipeline/machine.h>
 
+#define xnsched_realtime_domain  cobalt_pipeline.domain
+
 #define PIPELINE_NR_IRQS  IPIPE_NR_IRQS
 
 typedef unsigned long spl_t;

include/cobalt/kernel/sched.h

@@ -233,8 +233,6 @@ static inline void xnsched_set_self_resched(struct xnsched *sched)
 	sched->status |= XNRESCHED;
 }
 
-#define xnsched_realtime_domain  cobalt_pipeline.domain
-
 /* Set resched flag for the given scheduler. */
 #ifdef CONFIG_SMP
 

kernel/cobalt/ipipe/Makefile

@@ -2,4 +2,4 @@ ccflags-y += -I$(srctree)/kernel
 
 obj-y +=	pipeline.o
 
-pipeline-y :=	init.o intr.o kevents.o apc.o tick.o
+pipeline-y :=	init.o intr.o kevents.o apc.o tick.o syscall.o

kernel/cobalt/ipipe/syscall.c

+/*
+ * SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2005 Philippe Gerum <rpm@xenomai.org>
+ * Copyright (C) 2005 Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
+ */
+
+#include <pipeline/pipeline.h>
+#include <pipeline/kevents.h>
+#include <cobalt/kernel/assert.h>
+#include <xenomai/posix/syscall.h>
+
+int ipipe_syscall_hook(struct ipipe_domain *ipd, struct pt_regs *regs)
+{
+	if (unlikely(is_secondary_domain()))
+		return handle_root_syscall(regs);
+
+	return handle_head_syscall(ipd != &xnsched_realtime_domain, regs);
+}
+
+int ipipe_fastcall_hook(struct pt_regs *regs)
+{
+	int ret;
+
+	ret = handle_head_syscall(false, regs);
+	XENO_BUG_ON(COBALT, ret == KEVENT_PROPAGATE);
+
+	return ret;
+}

kernel/cobalt/posix/process.h

@@ -23,9 +23,6 @@
 #include <pipeline/thread.h>
 #include <cobalt/kernel/ppd.h>
 
-#define KEVENT_PROPAGATE   0
-#define KEVENT_STOP        1
-
 #define NR_PERSONALITIES  4
 #if BITS_PER_LONG < NR_PERSONALITIES
 #error "NR_PERSONALITIES overflows internal bitmap"

kernel/cobalt/posix/syscall.c

@@ -18,7 +18,6 @@
  */
 #include <linux/types.h>
 #include <linux/err.h>
-#include <linux/ipipe.h>
 #include <linux/sched.h>
 #include <linux/kconfig.h>
 #include <linux/unistd.h>
@@ -26,6 +25,7 @@
 #include <cobalt/kernel/tree.h>
 #include <cobalt/kernel/vdso.h>
 #include <cobalt/kernel/init.h>
+#include <pipeline/kevents.h>
 #include <asm/syscall.h>
 #include "internal.h"
 #include "thread.h"
@@ -475,7 +475,7 @@ static inline int allowed_syscall(struct cobalt_process *process,
 	return cap_raised(current_cap(), CAP_SYS_NICE);
 }
 
-static int handle_head_syscall(struct ipipe_domain *ipd, struct pt_regs *regs)
+int handle_head_syscall(bool caller_is_relaxed, struct pt_regs *regs)
 {
 	struct cobalt_process *process;
 	int switched, sigs, sysflags;
@@ -553,7 +553,7 @@ restart:
 		/*
 		 * The syscall must run from the Linux domain.
 		 */
-		if (ipd == &xnsched_realtime_domain) {
+		if (!caller_is_relaxed) {
 			/*
 			 * Request originates from the Xenomai domain:
 			 * relax the caller then invoke the syscall
@@ -578,7 +578,7 @@ restart:
 		 * hand it over to our secondary-mode dispatcher.
 		 * Otherwise, invoke the syscall handler immediately.
 		 */
-		if (ipd != &xnsched_realtime_domain)
+		if (caller_is_relaxed)
 			return KEVENT_PROPAGATE;
 	}
 
@@ -667,7 +667,7 @@ bad_syscall:
 	return KEVENT_STOP;
 }
 
-static int handle_root_syscall(struct ipipe_domain *ipd, struct pt_regs *regs)
+int handle_root_syscall(struct pt_regs *regs)
 {
 	int sysflags, switched, sigs;
 	struct xnthread *thread;
@@ -777,24 +777,6 @@ ret_handled:
 	return KEVENT_STOP;
 }
 
-int ipipe_syscall_hook(struct ipipe_domain *ipd, struct pt_regs *regs)
-{
-	if (unlikely(is_secondary_domain()))
-		return handle_root_syscall(ipd, regs);
-
-	return handle_head_syscall(ipd, regs);
-}
-
-int ipipe_fastcall_hook(struct pt_regs *regs)
-{
-	int ret;
-
-	ret = handle_head_syscall(&xnsched_realtime_domain, regs);
-	XENO_BUG_ON(COBALT, ret == KEVENT_PROPAGATE);
-
-	return ret;
-}
-
 long cobalt_restart_syscall_placeholder(struct restart_block *param)
 {
 	return -EINVAL;

kernel/cobalt/posix/syscall.h

@@ -20,6 +20,8 @@
 
 #include <cobalt/uapi/syscall.h>
 
+struct pt_regs;
+
 /* Regular (native) syscall handler implementation. */
 #define COBALT_SYSCALL(__name, __mode, __args)	\
 	long CoBaLt_ ## __name __args
@@ -30,4 +32,9 @@
 
 #include <asm/xenomai/syscall32.h>
 
+int handle_head_syscall(bool caller_is_relaxed,
+			struct pt_regs *regs);
+
+int handle_root_syscall(struct pt_regs *regs);
+
 #endif /* !_COBALT_POSIX_SYSCALL_H */