Re: [PATCH 08/19] arm64: introduce is_a32_task and is_a32_thread (for AArch32 compat)

["Zhangjian (Bamvor)" <bamvor.zhangjian@huawei.com>]

Hi,

On 2016/6/18 7:54, Yury Norov wrote:
> Based on patch of Andrew Pinski.
>
> This patch introduces is_a32_compat_task and is_a32_thread so it is
> easier to say this is a a32 specific thread or a generic compat thread/task.
> Corresponding functions are located in <asm/is_compat.h> to avoid mess in
> headers.
>
> Some files include both <linux/compat.h> and <asm/compat.h>,
> and this is wrong because <linux/compat.h> has <asm/compat.h> already
> included. It was fixed too.
>
> Signed-off-by: Yury Norov <ynorov@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: Andrew Pinski <Andrew.Pinski@caviumnetworks.com>
> Reviewed-by: David Daney <ddaney@caviumnetworks.com>
> ---
>   arch/arm64/include/asm/compat.h      | 19 ++---------
>   arch/arm64/include/asm/elf.h         | 10 +++---
>   arch/arm64/include/asm/ftrace.h      |  2 +-
>   arch/arm64/include/asm/is_compat.h   | 64 ++++++++++++++++++++++++++++++++++++
>   arch/arm64/include/asm/memory.h      |  5 +--
>   arch/arm64/include/asm/processor.h   |  5 +--
>   arch/arm64/include/asm/syscall.h     |  2 +-
>   arch/arm64/include/asm/thread_info.h |  2 +-
>   arch/arm64/kernel/hw_breakpoint.c    | 10 +++---
>   arch/arm64/kernel/perf_regs.c        |  2 +-
>   arch/arm64/kernel/process.c          |  7 ++--
>   arch/arm64/kernel/ptrace.c           | 11 +++----
>   arch/arm64/kernel/signal.c           |  4 +--
>   arch/arm64/kernel/traps.c            |  3 +-
>   14 files changed, 98 insertions(+), 48 deletions(-)
>   create mode 100644 arch/arm64/include/asm/is_compat.h
>
> diff --git a/arch/arm64/include/asm/compat.h b/arch/arm64/include/asm/compat.h
> index eb8432b..df2f72d 100644
> --- a/arch/arm64/include/asm/compat.h
> +++ b/arch/arm64/include/asm/compat.h
> @@ -24,6 +24,8 @@
>   #include <linux/types.h>
>   #include <linux/sched.h>
>
> +#include <asm/is_compat.h>
> +
>   #define COMPAT_USER_HZ		100
>   #ifdef __AARCH64EB__
>   #define COMPAT_UTS_MACHINE	"armv8b\0\0"
> @@ -298,23 +300,6 @@ struct compat_shmid64_ds {
>   	compat_ulong_t __unused5;
>   };
>
> -static inline int is_compat_task(void)
> -{
> -	return test_thread_flag(TIF_32BIT);
> -}
> -
> -static inline int is_compat_thread(struct thread_info *thread)
> -{
> -	return test_ti_thread_flag(thread, TIF_32BIT);
> -}
> -
> -#else /* !CONFIG_COMPAT */
> -
> -static inline int is_compat_thread(struct thread_info *thread)
> -{
> -	return 0;
> -}
> -
>   #endif /* CONFIG_COMPAT */
>   #endif /* __KERNEL__ */
>   #endif /* __ASM_COMPAT_H */
> diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
> index 579b6e6..bef2d90 100644
> --- a/arch/arm64/include/asm/elf.h
> +++ b/arch/arm64/include/asm/elf.h
> @@ -16,6 +16,10 @@
>   #ifndef __ASM_ELF_H
>   #define __ASM_ELF_H
>
> +#ifndef __ASSEMBLY__
> +#include <linux/compat.h>
> +#endif
> +
>   #include <asm/hwcap.h>
>
>   /*
> @@ -152,13 +156,9 @@ extern int arch_setup_additional_pages(struct linux_binprm *bprm,
>   				       int uses_interp);
>
>   /* 1GB of VA */
> -#ifdef CONFIG_COMPAT
> -#define STACK_RND_MASK			(test_thread_flag(TIF_32BIT) ? \
> +#define STACK_RND_MASK			(is_compat_task() ? \
>   						0x7ff >> (PAGE_SHIFT - 12) : \
>   						0x3ffff >> (PAGE_SHIFT - 12))
> -#else
> -#define STACK_RND_MASK			(0x3ffff >> (PAGE_SHIFT - 12))
> -#endif
>
>   #ifdef __AARCH64EB__
>   #define COMPAT_ELF_PLATFORM		("v8b")
> diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h
> index caa955f..0feb28a 100644
> --- a/arch/arm64/include/asm/ftrace.h
> +++ b/arch/arm64/include/asm/ftrace.h
> @@ -54,7 +54,7 @@ static inline unsigned long ftrace_call_adjust(unsigned long addr)
>   #define ARCH_TRACE_IGNORE_COMPAT_SYSCALLS
>   static inline bool arch_trace_is_compat_syscall(struct pt_regs *regs)
>   {
> -	return is_compat_task();
> +	return is_a32_compat_task();
>   }
>   #endif /* ifndef __ASSEMBLY__ */
>
> diff --git a/arch/arm64/include/asm/is_compat.h b/arch/arm64/include/asm/is_compat.h
> new file mode 100644
> index 0000000..8dba5ca
> --- /dev/null
> +++ b/arch/arm64/include/asm/is_compat.h
> @@ -0,0 +1,64 @@
> +/*
> + * 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/>.
> + */
> +
> +#ifndef __ASM_IS_COMPAT_H
> +#define __ASM_IS_COMPAT_H
> +#ifndef __ASSEMBLY__
> +
> +#include <linux/thread_bits.h>
> +
> +#ifdef CONFIG_AARCH32_EL0
> +
> +static inline int is_a32_compat_task(void)
> +{
> +	return test_thread_flag(TIF_32BIT);
> +}
> +
> +static inline int is_a32_compat_thread(struct thread_info *thread)
> +{
> +	return test_ti_thread_flag(thread, TIF_32BIT);
> +}
> +
> +#else
> +
> +static inline int is_a32_compat_task(void)
> +
> +{
> +	return 0;
> +}
> +
> +static inline int is_a32_compat_thread(struct thread_info *thread)
> +{
> +	return 0;
> +}
> +
> +#endif /* CONFIG_AARCH32_EL0 */
> +
> +#ifdef CONFIG_COMPAT
> +
> +static inline int is_compat_task(void)
> +{
> +	return is_a32_compat_task();
> +}
> +
> +#endif /* CONFIG_COMPAT */
> +
> +static inline int is_compat_thread(struct thread_info *thread)
> +{
> +	return is_a32_compat_thread(thread);
> +}
> +
> +
> +#endif /* !__ASSEMBLY__ */
> +#endif /* __ASM_IS_COMPAT_H */
> diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
> index 31b7322..4d734a1 100644
> --- a/arch/arm64/include/asm/memory.h
> +++ b/arch/arm64/include/asm/memory.h
> @@ -26,6 +26,7 @@
>   #include <linux/types.h>
>   #include <asm/bug.h>
>   #include <asm/sizes.h>
> +#include <asm/is_compat.h>
>
>   /*
>    * Allow for constants defined here to be used from assembly code
> @@ -78,9 +79,9 @@
>
>   #ifdef CONFIG_COMPAT
>   #define TASK_SIZE_32		UL(0x100000000)
> -#define TASK_SIZE		(test_thread_flag(TIF_32BIT) ? \
> +#define TASK_SIZE		(is_compat_task() ?		\
>   				TASK_SIZE_32 : TASK_SIZE_64)
> -#define TASK_SIZE_OF(tsk)	(test_tsk_thread_flag(tsk, TIF_32BIT) ? \
> +#define TASK_SIZE_OF(tsk)	(is_compat_thread(tsk) ? \
It should be
+#define TASK_SIZE_OF(tsk)      (is_compat_thread(task_thread_info(tsk)) ? \
is_compat_thread takes "struct thread_info *thread" while TASK_SIZE_OF takes
"struct task_struct *tsk"tsk.

Regards

Bamvor

>   				TASK_SIZE_32 : TASK_SIZE_64)
>   #else
>   #define TASK_SIZE		TASK_SIZE_64
> diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h
> index 5bbdbb4..1eccf47 100644
> --- a/arch/arm64/include/asm/processor.h
> +++ b/arch/arm64/include/asm/processor.h
> @@ -30,6 +30,7 @@
>   #include <linux/string.h>
>
>   #include <asm/alternative.h>
> +#include <asm/is_compat.h>
>   #include <asm/fpsimd.h>
>   #include <asm/hw_breakpoint.h>
>   #include <asm/lse.h>
> @@ -41,7 +42,7 @@
>   #define STACK_TOP_MAX		TASK_SIZE_64
>   #ifdef CONFIG_COMPAT
>   #define AARCH32_VECTORS_BASE	0xffff0000
> -#define STACK_TOP		(test_thread_flag(TIF_32BIT) ? \
> +#define STACK_TOP		(is_compat_task() ? \
>   				AARCH32_VECTORS_BASE : STACK_TOP_MAX)
>   #else
>   #define STACK_TOP		STACK_TOP_MAX
> @@ -94,7 +95,7 @@ struct thread_struct {
>   #define task_user_tls(t)						\
>   ({									\
>   	unsigned long *__tls;						\
> -	if (is_compat_thread(task_thread_info(t)))			\
> +	if (is_a32_compat_thread(task_thread_info(t)))			\
>   		__tls = &(t)->thread.tp2_value;				\
>   	else								\
>   		__tls = &(t)->thread.tp_value;				\
> diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h
> index 709a574..ce09641 100644
> --- a/arch/arm64/include/asm/syscall.h
> +++ b/arch/arm64/include/asm/syscall.h
> @@ -113,7 +113,7 @@ static inline void syscall_set_arguments(struct task_struct *task,
>    */
>   static inline int syscall_get_arch(void)
>   {
> -	if (is_compat_task())
> +	if (is_a32_compat_task())
>   		return AUDIT_ARCH_ARM;
>
>   	return AUDIT_ARCH_AARCH64;
> diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
> index abd64bd..4daa559 100644
> --- a/arch/arm64/include/asm/thread_info.h
> +++ b/arch/arm64/include/asm/thread_info.h
> @@ -118,7 +118,7 @@ static inline struct thread_info *current_thread_info(void)
>   #define TIF_FREEZE		19
>   #define TIF_RESTORE_SIGMASK	20
>   #define TIF_SINGLESTEP		21
> -#define TIF_32BIT		22	/* 32bit process */
> +#define TIF_32BIT		22	/* AARCH32 process */
>
>   #define _TIF_SIGPENDING		(1 << TIF_SIGPENDING)
>   #define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)
> diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
> index ce21aa8..d67f518 100644
> --- a/arch/arm64/kernel/hw_breakpoint.c
> +++ b/arch/arm64/kernel/hw_breakpoint.c
> @@ -164,7 +164,7 @@ enum hw_breakpoint_ops {
>   	HW_BREAKPOINT_RESTORE
>   };
>
> -static int is_compat_bp(struct perf_event *bp)
> +static int is_a32_compat_bp(struct perf_event *bp)
>   {
>   	struct task_struct *tsk = bp->hw.target;
>
> @@ -175,7 +175,7 @@ static int is_compat_bp(struct perf_event *bp)
>   	 * deprecated behaviour if we use unaligned watchpoints in
>   	 * AArch64 state.
>   	 */
> -	return tsk && is_compat_thread(task_thread_info(tsk));
> +	return tsk && is_a32_compat_thread(task_thread_info(tsk));
>   }
>
>   /**
> @@ -435,7 +435,7 @@ static int arch_build_bp_info(struct perf_event *bp)
>   	 * Watchpoints can be of length 1, 2, 4 or 8 bytes.
>   	 */
>   	if (info->ctrl.type == ARM_BREAKPOINT_EXECUTE) {
> -		if (is_compat_bp(bp)) {
> +		if (is_a32_compat_bp(bp)) {
>   			if (info->ctrl.len != ARM_BREAKPOINT_LEN_2 &&
>   			    info->ctrl.len != ARM_BREAKPOINT_LEN_4)
>   				return -EINVAL;
> @@ -492,7 +492,7 @@ int arch_validate_hwbkpt_settings(struct perf_event *bp)
>   	 * AArch32 tasks expect some simple alignment fixups, so emulate
>   	 * that here.
>   	 */
> -	if (is_compat_bp(bp)) {
> +	if (is_a32_compat_bp(bp)) {
>   		if (info->ctrl.len == ARM_BREAKPOINT_LEN_8)
>   			alignment_mask = 0x7;
>   		else
> @@ -679,7 +679,7 @@ static int watchpoint_handler(unsigned long addr, unsigned int esr,
>
>   		info = counter_arch_bp(wp);
>   		/* AArch32 watchpoints are either 4 or 8 bytes aligned. */
> -		if (is_compat_task()) {
> +		if (is_a32_compat_task()) {
>   			if (info->ctrl.len == ARM_BREAKPOINT_LEN_8)
>   				alignment_mask = 0x7;
>   			else
> diff --git a/arch/arm64/kernel/perf_regs.c b/arch/arm64/kernel/perf_regs.c
> index 3f62b35..a79058f 100644
> --- a/arch/arm64/kernel/perf_regs.c
> +++ b/arch/arm64/kernel/perf_regs.c
> @@ -45,7 +45,7 @@ int perf_reg_validate(u64 mask)
>
>   u64 perf_reg_abi(struct task_struct *task)
>   {
> -	if (is_compat_thread(task_thread_info(task)))
> +	if (is_a32_compat_thread(task_thread_info(task)))
>   		return PERF_SAMPLE_REGS_ABI_32;
>   	else
>   		return PERF_SAMPLE_REGS_ABI_64;
> diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c
> index 6cd2612..c008ec8 100644
> --- a/arch/arm64/kernel/process.c
> +++ b/arch/arm64/kernel/process.c
> @@ -47,7 +47,6 @@
>   #include <trace/events/power.h>
>
>   #include <asm/alternative.h>
> -#include <asm/compat.h>
>   #include <asm/cacheflush.h>
>   #include <asm/fpsimd.h>
>   #include <asm/mmu_context.h>
> @@ -204,7 +203,7 @@ static void tls_thread_flush(void)
>   {
>   	asm ("msr tpidr_el0, xzr");
>
> -	if (is_compat_task()) {
> +	if (is_a32_compat_task()) {
>   		current->thread.tp_value = 0;
>
>   		/*
> @@ -256,7 +255,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start,
>   		asm("mrs %0, tpidr_el0" : "=r" (*task_user_tls(p)));
>
>   		if (stack_start) {
> -			if (is_compat_thread(task_thread_info(p)))
> +			if (is_a32_compat_thread(task_thread_info(p)))
>   				childregs->compat_sp = stack_start;
>   			else
>   				childregs->sp = stack_start;
> @@ -293,7 +292,7 @@ static void tls_thread_switch(struct task_struct *next)
>   	*task_user_tls(current) = tpidr;
>
>   	tpidr = *task_user_tls(next);
> -	tpidrro = is_compat_thread(task_thread_info(next)) ?
> +	tpidrro = is_a32_compat_thread(task_thread_info(next)) ?
>   		  next->thread.tp_value : 0;
>
>   	asm(
> diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
> index aa79e81..38a09338 100644
> --- a/arch/arm64/kernel/ptrace.c
> +++ b/arch/arm64/kernel/ptrace.c
> @@ -38,7 +38,6 @@
>   #include <linux/tracehook.h>
>   #include <linux/elf.h>
>
> -#include <asm/compat.h>
>   #include <asm/debug-monitors.h>
>   #include <asm/pgtable.h>
>   #include <asm/syscall.h>
> @@ -85,7 +84,7 @@ static void ptrace_hbptriggered(struct perf_event *bp,
>   #ifdef CONFIG_AARCH32_EL0
>   	int i;
>
> -	if (!is_compat_task())
> +	if (!is_a32_compat_task())
>   		goto send_sig;
>
>   	for (i = 0; i < ARM_MAX_BRP; ++i) {
> @@ -1203,9 +1202,9 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
>   	 * 32-bit children use an extended user_aarch32_ptrace_view to allow
>   	 * access to the TLS register.
>   	 */
> -	if (is_compat_task())
> +	if (is_a32_compat_task())
>   		return &user_aarch32_view;
> -	else if (is_compat_thread(task_thread_info(task)))
> +	else if (is_a32_compat_thread(task_thread_info(task)))
>   		return &user_aarch32_ptrace_view;
>   #endif
>   	return &user_aarch64_view;
> @@ -1232,7 +1231,7 @@ static void tracehook_report_syscall(struct pt_regs *regs,
>   	 * A scratch register (ip(r12) on AArch32, x7 on AArch64) is
>   	 * used to denote syscall entry/exit:
>   	 */
> -	regno = (is_compat_task() ? 12 : 7);
> +	regno = (is_a32_compat_task() ? 12 : 7);
>   	saved_reg = regs->regs[regno];
>   	regs->regs[regno] = dir;
>
> @@ -1343,7 +1342,7 @@ int valid_user_regs(struct user_pt_regs *regs, struct task_struct *task)
>   	if (!test_tsk_thread_flag(task, TIF_SINGLESTEP))
>   		regs->pstate &= ~DBG_SPSR_SS;
>
> -	if (is_compat_thread(task_thread_info(task)))
> +	if (is_a32_compat_thread(task_thread_info(task)))
>   		return valid_compat_regs(regs);
>   	else
>   		return valid_native_regs(regs);
> diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
> index a8eafdb..be02f65 100644
> --- a/arch/arm64/kernel/signal.c
> +++ b/arch/arm64/kernel/signal.c
> @@ -276,7 +276,7 @@ static int setup_rt_frame(int usig, struct ksignal *ksig, sigset_t *set,
>
>   static void setup_restart_syscall(struct pt_regs *regs)
>   {
> -	if (is_compat_task())
> +	if (is_a32_compat_task())
>   		compat_setup_restart_syscall(regs);
>   	else
>   		regs->regs[8] = __NR_restart_syscall;
> @@ -295,7 +295,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
>   	/*
>   	 * Set up the stack frame
>   	 */
> -	if (is_compat_task()) {
> +	if (is_a32_compat_task()) {
>   		if (ksig->ka.sa.sa_flags & SA_SIGINFO)
>   			ret = compat_setup_rt_frame(usig, ksig, oldset, regs);
>   		else
> diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
> index 973faec..d77be17 100644
> --- a/arch/arm64/kernel/traps.c
> +++ b/arch/arm64/kernel/traps.c
> @@ -18,6 +18,7 @@
>    */
>
>   #include <linux/bug.h>
> +#include <linux/compat.h>
>   #include <linux/signal.h>
>   #include <linux/personality.h>
>   #include <linux/kallsyms.h>
> @@ -411,7 +412,7 @@ asmlinkage long do_ni_syscall(struct pt_regs *regs)
>   {
>   #ifdef CONFIG_AARCH32_EL0
>   	long ret;
> -	if (is_compat_task()) {
> +	if (is_a32_compat_task()) {
>   		ret = compat_arm_syscall(regs);
>   		if (ret != -ENOSYS)
>   			return ret;
>