From e9d04b25e6b1e8b4d84f6354f3f737e3e7b74446 Mon Sep 17 00:00:00 2001
From: milek7 <me@milek7.pl>
Date: Thu, 28 Apr 2022 22:01:39 +0200
Subject: [PATCH] arm64: Add thread exit syscall in commpage.

Change-Id: Ia8e7e4626add623735fefefa1af151b7338adc35
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5265
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>
Reviewed-by: waddlesplash <waddlesplash@gmail.com>
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>
---
 .../system/arch/arm64/arch_commpage_defs.h    |  2 ++
 src/system/kernel/arch/arm64/arch_asm.S       |  5 ++++
 .../kernel/arch/arm64/arch_commpage.cpp       | 30 +++++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/headers/private/system/arch/arm64/arch_commpage_defs.h b/headers/private/system/arch/arm64/arch_commpage_defs.h
index 0df827662c..2d2fd2502c 100644
--- a/headers/private/system/arch/arm64/arch_commpage_defs.h
+++ b/headers/private/system/arch/arm64/arch_commpage_defs.h
@@ -10,4 +10,6 @@
 #	error Must not be included directly. Include <commpage_defs.h> instead!
 #endif
 
+#define COMMPAGE_ENTRY_ARM64_THREAD_EXIT (COMMPAGE_ENTRY_FIRST_ARCH_SPECIFIC + 0)
+
 #endif	/* _SYSTEM_ARCH_ARM64_COMMPAGE_DEFS_H */
diff --git a/src/system/kernel/arch/arm64/arch_asm.S b/src/system/kernel/arch/arm64/arch_asm.S
index c71934e659..fae109f4e1 100644
--- a/src/system/kernel/arch/arm64/arch_asm.S
+++ b/src/system/kernel/arch/arm64/arch_asm.S
@@ -5,9 +5,14 @@
 #include <arch/arm/arch_cpu.h>
 #include <asm_defs.h>
 #include "asm_offsets.h"
+#include "syscall_numbers.h"
 
 .text
 
+FUNCTION(_thread_exit_syscall):
+	svc #((SYSCALL_EXIT_THREAD << 5) | 1)
+FUNCTION_END(_thread_exit_syscall)
+
 .macro xchg_sp xt
 add	sp, sp, \xt
 sub	\xt, sp, \xt
diff --git a/src/system/kernel/arch/arm64/arch_commpage.cpp b/src/system/kernel/arch/arm64/arch_commpage.cpp
index ab032ac152..2e9cf151d0 100644
--- a/src/system/kernel/arch/arm64/arch_commpage.cpp
+++ b/src/system/kernel/arch/arm64/arch_commpage.cpp
@@ -13,6 +13,33 @@
 #include <smp.h>
 
 
+extern "C" void _thread_exit_syscall();
+
+
+static void
+register_commpage_function(const char* functionName, int32 commpageIndex,
+	const char* commpageSymbolName, addr_t expectedAddress)
+{
+	// get address and size of function
+	elf_symbol_info symbolInfo;
+	if (elf_lookup_kernel_symbol(functionName, &symbolInfo) != B_OK) {
+		panic("register_commpage_function(): Failed to find signal frame function \"%s\"!",
+			functionName);
+	}
+
+	ASSERT(expectedAddress == symbolInfo.address);
+
+	// fill in the commpage table entry
+	addr_t position = fill_commpage_entry(commpageIndex, (void*)symbolInfo.address,
+		symbolInfo.size);
+
+	// add symbol to the commpage image
+	image_id image = get_commpage_image();
+	elf_add_memory_image_symbol(image, commpageSymbolName, position, symbolInfo.size,
+		B_SYMBOL_TYPE_TEXT);
+}
+
+
 status_t
 arch_commpage_init(void)
 {
@@ -23,5 +50,8 @@ arch_commpage_init(void)
 status_t
 arch_commpage_init_post_cpus(void)
 {
+	register_commpage_function("_thread_exit_syscall", COMMPAGE_ENTRY_ARM64_THREAD_EXIT,
+		"commpage_thread_exit", (addr_t)&_thread_exit_syscall);
+
 	return B_OK;
 }