[PATCH 19/23] arm64: signal: share lp64 signal routines to ilp32

From: Yury Norov
Date: Mon May 23 2016 - 20:06:31 EST

After that, it will be possible to reuse it in ilp32.

Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxxxxxxxxx>
---
arch/arm64/include/asm/signal_common.h | 33 ++++++++++++
arch/arm64/kernel/signal.c | 91 +++++++++++++++++++++-------------
2 files changed, 90 insertions(+), 34 deletions(-)
create mode 100644 arch/arm64/include/asm/signal_common.h

diff --git a/arch/arm64/include/asm/signal_common.h b/arch/arm64/include/asm/signal_common.h
new file mode 100644
index 0000000..756ed2c
--- /dev/null
+++ b/arch/arm64/include/asm/signal_common.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 1995-2009 Russell King
+ * Copyright (C) 2012 ARM Ltd.
+ * Copyright (C) 2016 Cavium Networks.
+ *
+ * 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_SIGNAL_COMMON_H
+#define __ASM_SIGNAL_COMMON_H
+
+#include <linux/uaccess.h>
+#include <asm/ucontext.h>
+#include <asm/fpsimd.h>
+
+int preserve_fpsimd_context(struct fpsimd_context __user *ctx);
+int restore_fpsimd_context(struct fpsimd_context __user *ctx);
+int setup_sigcontext(struct sigcontext __user *uc_mcontext, struct pt_regs *regs);
+int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sf);
+void setup_return(struct pt_regs *regs, struct k_sigaction *ka,
+ void __user *frame, off_t sigframe_off, int usig);
+
+#endif /* __ASM_SIGNAL_COMMON_H */
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index be02f65..f9fbf8a 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -34,18 +34,23 @@
#include <asm/fpsimd.h>
#include <asm/signal32.h>
#include <asm/vdso.h>
+#include <asm/signal_common.h>
+
+struct sigframe {
+ struct ucontext uc;
+ u64 fp;
+ u64 lr;
+};

/*
* Do a signal return; undo the signal stack. These are aligned to 128-bit.
*/
struct rt_sigframe {
struct siginfo info;
- struct ucontext uc;
- u64 fp;
- u64 lr;
+ struct sigframe sig;
};

-static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
+int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
{
struct fpsimd_state *fpsimd = &current->thread.fpsimd_state;
int err;
@@ -65,7 +70,7 @@ static int preserve_fpsimd_context(struct fpsimd_context __user *ctx)
return err ? -EFAULT : 0;
}

-static int restore_fpsimd_context(struct fpsimd_context __user *ctx)
+int restore_fpsimd_context(struct fpsimd_context __user *ctx)
{
struct fpsimd_state fpsimd;
__u32 magic, size;
@@ -93,22 +98,30 @@ static int restore_fpsimd_context(struct fpsimd_context __user *ctx)
}

static int restore_sigframe(struct pt_regs *regs,
- struct rt_sigframe __user *sf)
+ struct sigframe __user *sf)
{
sigset_t set;
- int i, err;
- void *aux = sf->uc.uc_mcontext.__reserved;
-
+ int err;
err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
if (err == 0)
set_current_blocked(&set);

+ err |= restore_sigcontext(regs, &sf->uc.uc_mcontext);
+ return err;
+}
+
+
+int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *uc_mcontext)
+{
+ int i, err = 0;
+ void *aux = uc_mcontext->__reserved;
+
for (i = 0; i < 31; i++)
- __get_user_error(regs->regs[i], &sf->uc.uc_mcontext.regs[i],
+ __get_user_error(regs->regs[i], &uc_mcontext->regs[i],
err);
- __get_user_error(regs->sp, &sf->uc.uc_mcontext.sp, err);
- __get_user_error(regs->pc, &sf->uc.uc_mcontext.pc, err);
- __get_user_error(regs->pstate, &sf->uc.uc_mcontext.pstate, err);
+ __get_user_error(regs->sp, &uc_mcontext->sp, err);
+ __get_user_error(regs->pc, &uc_mcontext->pc, err);
+ __get_user_error(regs->pstate, &uc_mcontext->pstate, err);

/*
* Avoid sys_rt_sigreturn() restarting.
@@ -145,10 +158,10 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
if (!access_ok(VERIFY_READ, frame, sizeof (*frame)))
goto badframe;

- if (restore_sigframe(regs, frame))
+ if (restore_sigframe(regs, &frame->sig))
goto badframe;

- if (restore_altstack(&frame->uc.uc_stack))
+ if (restore_altstack(&frame->sig.uc.uc_stack))
goto badframe;

return regs->regs[0];
@@ -162,27 +175,36 @@ badframe:
return 0;
}

-static int setup_sigframe(struct rt_sigframe __user *sf,
+static int setup_sigframe(struct sigframe __user *sf,
struct pt_regs *regs, sigset_t *set)
{
- int i, err = 0;
- void *aux = sf->uc.uc_mcontext.__reserved;
- struct _aarch64_ctx *end;
+ int err = 0;

/* set up the stack frame for unwinding */
__put_user_error(regs->regs[29], &sf->fp, err);
__put_user_error(regs->regs[30], &sf->lr, err);
+ err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
+ err |= setup_sigcontext(&sf->uc.uc_mcontext, regs);
+
+ return err;
+}
+
+int setup_sigcontext(struct sigcontext __user *uc_mcontext,
+ struct pt_regs *regs)
+{
+ void *aux = uc_mcontext->__reserved;
+ struct _aarch64_ctx *end;
+ int i, err = 0;

for (i = 0; i < 31; i++)
- __put_user_error(regs->regs[i], &sf->uc.uc_mcontext.regs[i],
+ __put_user_error(regs->regs[i], &uc_mcontext->regs[i],
err);
- __put_user_error(regs->sp, &sf->uc.uc_mcontext.sp, err);
- __put_user_error(regs->pc, &sf->uc.uc_mcontext.pc, err);
- __put_user_error(regs->pstate, &sf->uc.uc_mcontext.pstate, err);

- __put_user_error(current->thread.fault_address, &sf->uc.uc_mcontext.fault_address, err);
+ __put_user_error(regs->sp, &uc_mcontext->sp, err);
+ __put_user_error(regs->pc, &uc_mcontext->pc, err);
+ __put_user_error(regs->pstate, &uc_mcontext->pstate, err);

- err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
+ __put_user_error(current->thread.fault_address, &uc_mcontext->fault_address, err);

if (err == 0) {
struct fpsimd_context *fpsimd_ctx =
@@ -229,14 +251,14 @@ static struct rt_sigframe __user *get_sigframe(struct ksignal *ksig,
return frame;
}

-static void setup_return(struct pt_regs *regs, struct k_sigaction *ka,
- void __user *frame, int usig)
+void setup_return(struct pt_regs *regs, struct k_sigaction *ka,
+ void __user *frame, off_t sigframe_off, int usig)
{
__sigrestore_t sigtramp;

regs->regs[0] = usig;
regs->sp = (unsigned long)frame;
- regs->regs[29] = regs->sp + offsetof(struct rt_sigframe, fp);
+ regs->regs[29] = regs->sp + sigframe_off + offsetof(struct sigframe, fp);
regs->pc = (unsigned long)ka->sa.sa_handler;

if (ka->sa.sa_flags & SA_RESTORER)
@@ -257,17 +279,18 @@ static int setup_rt_frame(int usig, struct ksignal *ksig, sigset_t *set,
if (!frame)
return 1;

- __put_user_error(0, &frame->uc.uc_flags, err);
- __put_user_error(NULL, &frame->uc.uc_link, err);
+ __put_user_error(0, &frame->sig.uc.uc_flags, err);
+ __put_user_error(NULL, &frame->sig.uc.uc_link, err);

- err |= __save_altstack(&frame->uc.uc_stack, regs->sp);
- err |= setup_sigframe(frame, regs, set);
+ err |= __save_altstack(&frame->sig.uc.uc_stack, regs->sp);
+ err |= setup_sigframe(&frame->sig, regs, set);
if (err == 0) {
- setup_return(regs, &ksig->ka, frame, usig);
+ setup_return(regs, &ksig->ka, frame,
+ offsetof(struct rt_sigframe, sig), usig);
if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
err |= copy_siginfo_to_user(&frame->info, &ksig->info);
regs->regs[1] = (unsigned long)&frame->info;
- regs->regs[2] = (unsigned long)&frame->uc;
+ regs->regs[2] = (unsigned long)&frame->sig.uc;
}
}

--
2.5.0