feat: init package

Kbuild

@@ -0,0 +1,26 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for LoongArch old-world syscall compatible layer.
+#
+
+ifdef KBUILD_EXTMOD
+CONFIG_LOONGARCH_OW_SYSCALL := m
+endif
+
+obj-$(CONFIG_LOONGARCH_OW_SYSCALL) += la_ow_syscall.o
+la_ow_syscall-y += fsstat.o la_ow_syscall_main.o signal.o
+
+ifndef KBUILD_EXTMOD
+  ifdef CONFIG_KALLSYMS
+    ifndef CONFIG_RANDOMIZE_BASE
+$(obj)/ksym_addr.h: System.map
+	@$(kecho) '  GEN     $@'
+	$(Q)grep ' sys_call_table$$' $< >/dev/null
+	$(Q)grep ' kallsyms_lookup_name$$' $< >/dev/null
+	$(Q)echo "#define LAOWSYS_SYS_CALL_TABLE_ADDR 0x$$(grep ' sys_call_table$$' $< | cut -d ' ' -f 1)" > $@
+	$(Q)echo "#define LAOWSYS_KALLSYMS_LOOKUP_NAME_ADDR 0x$$(grep ' kallsyms_lookup_name$$' $< | cut -d ' ' -f 1)" >> $@
+ccflags-y += -DHAVE_KSYM_ADDR
+$(obj)/$(la_ow_syscall-y): $(obj)/ksym_addr.h
+    endif
+  endif
+endif

Makefile

@@ -0,0 +1,37 @@
+obj-m += la_ow_syscall.o fsstat.o la_ow_syscall_main.o signal.o
+
+KVER ?= $(shell uname -r)
+KDIR ?= /lib/modules/$(KVER)/build
+VERSION ?= $(shell cat VERSION)
+
+default:
+	$(MAKE) -C $(KDIR) M=$(CURDIR) modules
+
+clean:
+	$(MAKE) -C $(KDIR) M=$(CURDIR) clean
+
+install:
+	$(MAKE) -C $(KDIR) M=$(CURDIR) modules_install
+
+dkms.conf: dkms.conf.in
+	m4 -DVERSION=$(VERSION) $^ > $@
+
+dkms-add: dkms.conf
+	/usr/sbin/dkms add $(CURDIR)
+
+dkms-build: dkms.conf
+	/usr/sbin/dkms build la_ow_syscall/$(VERSION)
+
+dkms-install: dkms.conf
+	/usr/sbin/dkms install la_ow_syscall/$(VERSION)
+
+dkms-remove: dkms.conf
+	/usr/sbin/dkms remove la_ow_syscall/$(VERSION) --all
+
+modprobe-install:
+	modprobe la_ow_syscall
+
+modprobe-remove:
+	modprobe -r la_ow_syscall
+
+dev: modprobe-remove dkms-remove dkms-add dkms-build dkms-install modprobe-install

README.md

@@ -1 +1,77 @@
-# template-repository
+la\_ow\_syscall
+====
+
+This kernel modules provides compatibility with LoongArch's old-world ABI,
+making it possible to run old-world applications (such as Kingsoft's WPS Office
+and Tencent QQ) transparently on new-world (ABI 2.0) kernels and userspaces.
+
+Requirements
+----
+
+Linux Kernel >= 6.1.0 for `loongarch64` with the following option(s) set:
+
+- `CONFIG_KALLSYMS=y` (for reading kernel symbol addresses).
+- `CONFIG_KPROBES=y` (for probing kernel symbol addresses using kernels where
+  base address randomisation - `CONFIG_RANDOMIZE_BASE` - is enabled).
+
+Installation
+----
+
+You may install this kernel both as an in-tree module, an out-of-tree DKMS
+dynamic module, or a version-specific module. You may pick any option that best
+suits your needs.
+
+### In-tree module
+
+Copy this source tree as `arch/loongarch/ow_syscall` in your kernel tree and
+append the following to `arch/loongarch/Kbuild`:
+
+```
+obj-y += ow_syscall/
+```
+
+After building the kernel with `make`, run the following command to build the
+kernel module:
+
+```
+# $PWD is containing built objects
+# /path/to/source_dir is containing Linux source code
+make \
+    -C /path/to/source_dir \
+    ARCH=loongarch \
+    O="$PWD" \
+    arch/loongarch/ow_syscall/la_ow_syscall.ko \
+    CONFIG_LOONGARCH_OW_SYSCALL=m
+```
+
+Upon completion, copy the kernel module in place
+(`/lib/modules/.../arch/loongarch/ow_syscall/la_ow_syscall.ko`) and
+re-generate modules.dep and map files:
+
+```
+depmod
+```
+
+### DKMS dynamic module
+
+Generate a `dkms.conf`:
+
+```
+make dkms.conf
+```
+
+For installation and version management, refer to dkms(8) for details.
+
+### Version-specific module
+
+Build the kernel module:
+
+```
+make
+```
+
+Load the module with super user or root privilege:
+
+```
+insmod la_ow_syscall.ko
+```

VERSION

@@ -0,0 +1 @@
+0.1.0

debian/changelog

@@ -1,5 +1,5 @@
-template-repository (1.0-1) unstable; urgency=medium
+liblol-dkms (0.1.0) unstable; urgency=low
 
-  * Initial release
+  * Initial build
 
- -- Tsic404 <[email protected]>  Sat, 28 Jan 2023 13:46:49 +0800
+ -- Miao Wang <[email protected]>  Sun, 28 Jan 2024 09:12:00 +0800

debian/control

@@ -1,15 +1,16 @@
-Source: template-repository
-Section: unknown
-Priority: optional
-Maintainer: Tsic404 <[email protected]>
-Build-Depends: debhelper (>= 11)
-Standards-Version: 4.1.3
-Homepage: https://github.com/deepin-community/template-repository
-#Vcs-Browser: https://salsa.debian.org/debian/deepin-community-template-repository
-#Vcs-Git: https://salsa.debian.org/debian/deepin-community-template-repository.git
+Source: liblol-dkms
+Section: kernel
+Priority: extra
+Maintainer: Miao Wang <[email protected]>
+Build-Depends: debhelper-compat (= 13),
+               dkms, dh-dkms,
+Standards-Version: 4.6.2
+Homepage: https://github.com/AOSC-Dev/la_ow_syscall
 
-Package: template-repository
-Architecture: any
-Depends: ${shlibs:Depends}, ${misc:Depends}
-Description: <insert up to 60 chars description>
- <insert long description, indented with spaces>
+Package: liblol-dkms
+Architecture: loong64
+Depends: ${misc:Depends}, dkms
+Conflicts: glibc
+Description: Compatibility layer kmod for old world applications
+  This package contains a compatibility layer for old world
+  applications on new world loongarch64 platform.

debian/dkms

@@ -0,0 +1 @@
+dkms.conf

debian/install

@@ -0,0 +1,2 @@
+/usr/src/la_ow_syscall-*/*
+/usr/lib/modules-load.d/liblol.conf

debian/kmod-autoload.conf

@@ -0,0 +1,2 @@
+# Load the la_ow_syscall kernel module for old-world compatibility.
+la_ow_syscall

debian/rules

@@ -1,4 +1,31 @@
 #!/usr/bin/make -f
 
+include /usr/share/dpkg/pkg-info.mk
+
 %:
-	dh $@
+	dh $@ --with dkms
+
+override_dh_auto_build:
+	make dkms.conf VERSION="#MODULE_VERSION#"
+
+override_dh_auto_clean:
+	rm -rf dkms.conf
+
+TMPDIR ?= debian/tmp
+
+override_dh_auto_install:
+	install -Dvm644 \
+		Kbuild \
+		Makefile \
+		fsstat.c \
+		fsstat.h \
+		la_ow_syscall_main.c \
+		signal.c \
+		signal.h \
+		-t $(TMPDIR)/usr/src/la_ow_syscall-$(DEB_VERSION_UPSTREAM)
+	install -Dvm644 \
+		debian/kmod-autoload.conf \
+		$(TMPDIR)/usr/lib/modules-load.d/liblol.conf
+
+override_dh_dkms:
+	dh_dkms -V $(DEB_VERSION_UPSTREAM)

debian/source/format

@@ -1 +1 @@
-3.0 (quilt)
+3.0 (native)

dkms.conf.in

@@ -0,0 +1,11 @@
+PACKAGE_NAME="la_ow_syscall"
+PACKAGE_VERSION="VERSION"
+
+BUILD_EXCLUSIVE_KERNEL_MIN="5.19"
+BUILD_EXCLUSIVE_CONFIG="CONFIG_KALLSYMS"
+
+MAKE="KDIR=/lib/modules/${kernelver}/build make"
+CLEAN="make clean"
+BUILT_MODULE_NAME[0]="$PACKAGE_NAME"
+AUTOINSTALL="yes"
+DEST_MODULE_LOCATION[0]="/extra"

fsstat.c

@@ -0,0 +1,84 @@
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/mm.h>
+#include "fsstat.h"
+
+#define INIT_STRUCT_STAT_PADDING(st) memset(&st, 0, sizeof(st))
+
+struct __old_kernel_stat {
+	unsigned short st_dev;
+	unsigned short st_ino;
+	unsigned short st_mode;
+	unsigned short st_nlink;
+	unsigned short st_uid;
+	unsigned short st_gid;
+	unsigned short st_rdev;
+	unsigned int st_size;
+	unsigned int st_atime;
+	unsigned int st_mtime;
+	unsigned int st_ctime;
+};
+
+static int cp_new_stat(struct kstat *stat, struct stat __user *statbuf)
+{
+	struct stat tmp;
+
+	if (sizeof(tmp.st_dev) < 4 && !old_valid_dev(stat->dev))
+		return -EOVERFLOW;
+	if (sizeof(tmp.st_rdev) < 4 && !old_valid_dev(stat->rdev))
+		return -EOVERFLOW;
+#if BITS_PER_LONG == 32
+	if (stat->size > MAX_NON_LFS)
+		return -EOVERFLOW;
+#endif
+
+	INIT_STRUCT_STAT_PADDING(tmp);
+	tmp.st_dev = new_encode_dev(stat->dev);
+	tmp.st_ino = stat->ino;
+	if (sizeof(tmp.st_ino) < sizeof(stat->ino) && tmp.st_ino != stat->ino)
+		return -EOVERFLOW;
+	tmp.st_mode = stat->mode;
+	tmp.st_nlink = stat->nlink;
+	if (tmp.st_nlink != stat->nlink)
+		return -EOVERFLOW;
+	SET_UID(tmp.st_uid, from_kuid_munged(current_user_ns(), stat->uid));
+	SET_GID(tmp.st_gid, from_kgid_munged(current_user_ns(), stat->gid));
+	tmp.st_rdev = new_encode_dev(stat->rdev);
+	tmp.st_size = stat->size;
+	tmp.st_atime = stat->atime.tv_sec;
+	tmp.st_mtime = stat->mtime.tv_sec;
+	tmp.st_ctime = stat->ctime.tv_sec;
+#ifdef STAT_HAVE_NSEC
+	tmp.st_atime_nsec = stat->atime.tv_nsec;
+	tmp.st_mtime_nsec = stat->mtime.tv_nsec;
+	tmp.st_ctime_nsec = stat->ctime.tv_nsec;
+#endif
+	tmp.st_blocks = stat->blocks;
+	tmp.st_blksize = stat->blksize;
+	return copy_to_user(statbuf, &tmp, sizeof(tmp)) ? -EFAULT : 0;
+}
+
+__SYSCALL_DEFINEx(2, _newfstat, unsigned int, fd, struct stat __user *, statbuf)
+{
+	struct kstat stat;
+	int error = p_vfs_fstat(fd, &stat);
+
+	if (!error)
+		error = cp_new_stat(&stat, statbuf);
+
+	return error;
+}
+
+__SYSCALL_DEFINEx(4, _newfstatat, int, dfd, const char __user *, filename,
+		  struct stat __user *, statbuf, int, flag)
+{
+	struct kstat stat;
+	int error;
+
+	error = p_vfs_fstatat(dfd, filename, &stat, flag);
+	if (error)
+		return error;
+	return cp_new_stat(&stat, statbuf);
+}

fsstat.h

@@ -0,0 +1,3 @@
+extern int (*p_vfs_fstatat)(int dfd, const char __user *filename,
+			    struct kstat *stat, int flags);
+extern int (*p_vfs_fstat)(int fd, struct kstat *stat);