[PATCH v6 14/19] arm64:ilp32: add sys_ilp32.c and a separate table (in entry.S) to use it

Yury Norov
2015-11-17T21:16:54Z

From: Andrew Pinski <apinski@cavium.com>

Add a separate syscall-table for ILP32, which dispatches either to native
LP64 system call implementation or to compat-syscalls, as appropriate.

Reviewed-by: David Daney <ddaney@caviumnetworks.com>

Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>
Signed-off-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
---
arch/arm64/include/asm/unistd.h | 7 ++-
arch/arm64/kernel/Makefile | 1 +
arch/arm64/kernel/entry.S | 12 +++-
arch/arm64/kernel/sys_ilp32.c | 118 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 136 insertions(+), 2 deletions(-)
create mode 100644 arch/arm64/kernel/sys_ilp32.c

diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h
index 4c2cbbc..696e638 100644
--- a/arch/arm64/include/asm/unistd.h
+++ b/arch/arm64/include/asm/unistd.h
@@ -13,13 +13,16 @@
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
+#ifdef CONFIG_ARM64_ILP32
+#define __ARCH_WANT_COMPAT_SYS_PREADV64
+#define __ARCH_WANT_COMPAT_SYS_PWRITEV64
+#endif
#ifdef CONFIG_AARCH32_EL0
#define __ARCH_WANT_COMPAT_SYS_GETDENTS64
#define __ARCH_WANT_COMPAT_STAT64
#define __ARCH_WANT_SYS_GETHOSTNAME
#define __ARCH_WANT_SYS_PAUSE
#define __ARCH_WANT_SYS_GETPGRP
-#define __ARCH_WANT_SYS_LLSEEK
#define __ARCH_WANT_SYS_NICE
#define __ARCH_WANT_SYS_SIGPENDING
#define __ARCH_WANT_SYS_SIGPROCMASK
@@ -39,6 +42,8 @@
#define __NR_compat_sigreturn 119
#define __NR_compat_rt_sigreturn 173

+#define __ARCH_WANT_SYS_LLSEEK
+
/*
* The following SVCs are ARM private.
*/
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 35a59af..837d730 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -24,6 +24,7 @@ arm64-obj-$(CONFIG_AARCH32_EL0) += sys32.o kuser32.o signal32.o \
sys_compat.o entry32.o \
../../arm/kernel/opcodes.o
arm64-obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o entry-ftrace.o
+arm64-obj-$(CONFIG_ARM64_ILP32) += sys_ilp32.o
arm64-obj-$(CONFIG_COMPAT) += entry32-common.o
arm64-obj-$(CONFIG_MODULES) += arm64ksyms.o module.o
arm64-obj-$(CONFIG_PERF_EVENTS) += perf_regs.o perf_callchain.o
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 52be5c8..bcd921a 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -664,9 +664,13 @@ ENDPROC(ret_from_fork)
*/
.align 6
el0_svc:
- adrp stbl, sys_call_table // load syscall table pointer
uxtw scno, w8 // syscall number in w8
mov sc_nr, #__NR_syscalls
+#ifdef CONFIG_ARM64_ILP32
+ ldr x16, [tsk, #TI_FLAGS]
+ tbnz x16, #TIF_32BIT_AARCH64, el0_ilp32_svc // We are using ILP32
+#endif
+ adrp stbl, sys_call_table // load syscall table pointer
el0_svc_naked: // compat entry point
stp x0, scno, [sp, #S_ORIG_X0] // save the original x0 and syscall number
enable_dbg_and_irq
@@ -686,6 +690,12 @@ ni_sys:
b ret_fast_syscall
ENDPROC(el0_svc)

+#ifdef CONFIG_ARM64_ILP32
+el0_ilp32_svc:
+ adrp stbl, sys_call_ilp32_table // load syscall table pointer
+ b el0_svc_naked
+#endif
+
/*
* This is the really slow path. We're going to be doing context
* switches, and waiting for our parent to respond.
diff --git a/arch/arm64/kernel/sys_ilp32.c b/arch/arm64/kernel/sys_ilp32.c
new file mode 100644
index 0000000..c366d92
--- /dev/null
+++ b/arch/arm64/kernel/sys_ilp32.c
@@ -0,0 +1,118 @@
+/*
+ * AArch64- ILP32 specific system calls implementation
+ *
+ * Copyright (C) 2015 Cavium Inc.
+ * Author: Andrew Pinski <apinski@cavium.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/msg.h>
+#include <linux/export.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/compat.h>
+
+/*
+ * Wrappers to pass the pt_regs argument.
+ */
+asmlinkage long sys_rt_sigreturn_wrapper(void);
+#define compat_sys_rt_sigreturn sys_rt_sigreturn_wrapper
+
+/* Using non-compat syscalls where necessary */
+#define compat_sys_fadvise64_64 sys_fadvise64_64
+#define compat_sys_fallocate sys_fallocate
+#define compat_sys_ftruncate64 sys_ftruncate
+#define compat_sys_pread64 sys_pread64
+#define compat_sys_pwrite64 sys_pwrite64
+#define compat_sys_readahead sys_readahead
+#define compat_sys_rt_sigaction sys_rt_sigaction
+#define compat_sys_shmat sys_shmat
+#define compat_sys_sync_file_range sys_sync_file_range
+#define compat_sys_truncate64 sys_truncate
+#define compat_sys_sigaltstack sys_sigaltstack
+
+#define compat_sys_io_getevents sys_io_getevents
+#define compat_sys_lookup_dcookie sys_lookup_dcookie
+#define compat_sys_epoll_pwait sys_epoll_pwait
+#define compat_sys_fcntl64 compat_sys_fcntl
+#define compat_sys_preadv compat_sys_preadv64
+#define compat_sys_signalfd4 sys_signalfd4
+
+#define compat_sys_rt_sigsuspend sys_rt_sigsuspend
+#define compat_sys_rt_sigprocmask sys_rt_sigprocmask
+#define compat_sys_rt_sigpending sys_rt_sigpending
+#define compat_sys_rt_sigqueueinfo sys_rt_sigqueueinfo
+#define compat_sys_semtimedop sys_semtimedop
+#define compat_sys_rt_tgsigqueueinfo sys_rt_tgsigqueueinfo
+
+#define compat_sys_timer_create sys_timer_create
+#define compat_sys_timer_gettime sys_timer_gettime
+#define compat_sys_timer_settime sys_timer_settime
+#define compat_sys_rt_sigtimedwait sys_rt_sigtimedwait
+
+#define compat_sys_mq_open sys_mq_open
+#define compat_sys_mq_timedsend sys_mq_timedsend
+#define compat_sys_mq_timedreceive sys_mq_timedreceive
+#define compat_sys_mq_getsetattr sys_mq_getsetattr
+#define compat_sys_mq_open sys_mq_open
+
+#define compat_sys_open_by_handle_at sys_open_by_handle_at
+#define compat_sys_clock_adjtime sys_clock_adjtime
+
+#define compat_sys_openat sys_openat
+#define compat_sys_getdents64 sys_getdents64
+#define compat_sys_waitid sys_waitid
+#define compat_sys_timer_settime sys_timer_settime
+#define compat_sys_sched_rr_get_interval sys_sched_rr_get_interval
+#define compat_sys_execveat sys_execveat
+
+#define compat_sys_mq_notify sys_mq_notify
+#define compat_sys_clock_nanosleep sys_clock_nanosleep
+#define compat_sys_clock_getres sys_clock_getres
+
+#define sys_lseek sys_llseek
+
+asmlinkage long compat_sys_mmap2_wrapper(void);
+#define sys_mmap2 compat_sys_mmap2_wrapper
+
+asmlinkage long compat_sys_fstatfs64_wrapper(void);
+#define compat_sys_fstatfs64 compat_sys_fstatfs64_wrapper
+asmlinkage long compat_sys_statfs64_wrapper(void);
+#define compat_sys_statfs64 compat_sys_statfs64_wrapper
+
+#define compat_sys_pwritev compat_sys_pwritev64
+
+#include <asm/syscall.h>
+
+#undef __SYSCALL
+#undef __SC_COMP
+#undef __SC_3264
+#undef __SC_COMP_3264
+
+#define __SYSCALL_COMPAT
+#define __SYSCALL(nr, sym) [nr] = sym,
+
+/*
+ * The sys_call_ilp32_table array must be 4K aligned to be accessible from
+ * kernel/entry.S.
+ */
+void *sys_call_ilp32_table[__NR_syscalls] __aligned(4096) = {
+ [0 ... __NR_syscalls - 1] = sys_ni_syscall,
+#include <asm/unistd.h>
+};
--
2.1.4