[patch 07/10] x86/fpu/signal: Change return type of fpu__restore_sig() to boolean

From: Thomas Gleixner
Date: Mon Aug 30 2021 - 12:27:43 EST


None of the call sites cares about the error code. All they need to know is
whether the function succeeded or not.

Suggested-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
arch/x86/ia32/ia32_signal.c | 2 +-
arch/x86/include/asm/fpu/internal.h | 2 +-
arch/x86/kernel/fpu/signal.c | 22 ++++++++++------------
arch/x86/kernel/signal.c | 4 ++--
4 files changed, 14 insertions(+), 16 deletions(-)

--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -94,7 +94,7 @@ static bool ia32_restore_sigcontext(stru
* normal case.
*/
reload_segments(&sc);
- return !fpu__restore_sig(compat_ptr(sc.fpstate), 1);
+ return fpu__restore_sig(compat_ptr(sc.fpstate), 1);
}

COMPAT_SYSCALL_DEFINE0(sigreturn)
--- a/arch/x86/include/asm/fpu/internal.h
+++ b/arch/x86/include/asm/fpu/internal.h
@@ -26,7 +26,7 @@
/*
* High level FPU state handling functions:
*/
-extern int fpu__restore_sig(void __user *buf, int ia32_frame);
+extern bool fpu__restore_sig(void __user *buf, int ia32_frame);
extern void fpu__drop(struct fpu *fpu);
extern void fpu__clear_user_states(struct fpu *fpu);
extern int fpu__exception_code(struct fpu *fpu, int trap_nr);
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -434,17 +434,17 @@ static inline int xstate_sigframe_size(v
/*
* Restore FPU state from a sigframe:
*/
-int fpu__restore_sig(void __user *buf, int ia32_frame)
+bool fpu__restore_sig(void __user *buf, int ia32_frame)
{
unsigned int size = xstate_sigframe_size();
struct fpu *fpu = &current->thread.fpu;
void __user *buf_fx = buf;
bool ia32_fxstate = false;
- int ret;
+ bool success = false;

if (unlikely(!buf)) {
fpu__clear_user_states(fpu);
- return 0;
+ return true;
}

ia32_frame &= (IS_ENABLED(CONFIG_X86_32) ||
@@ -460,23 +460,21 @@ int fpu__restore_sig(void __user *buf, i
ia32_fxstate = true;
}

- if (!access_ok(buf, size)) {
- ret = -EACCES;
+ if (!access_ok(buf, size))
goto out;
- }

if (!IS_ENABLED(CONFIG_X86_64) && !cpu_feature_enabled(X86_FEATURE_FPU)) {
- ret = fpregs_soft_set(current, NULL, 0,
- sizeof(struct user_i387_ia32_struct),
- NULL, buf);
+ success = !fpregs_soft_set(current, NULL, 0,
+ sizeof(struct user_i387_ia32_struct),
+ NULL, buf);
} else {
- ret = __fpu_restore_sig(buf, buf_fx, ia32_fxstate);
+ success = !__fpu_restore_sig(buf, buf_fx, ia32_fxstate);
}

out:
- if (unlikely(ret))
+ if (unlikely(!success))
fpu__clear_user_states(fpu);
- return ret;
+ return success;
}

unsigned long
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -136,8 +136,8 @@ static bool restore_sigcontext(struct pt
force_valid_ss(regs);
#endif

- return !fpu__restore_sig((void __user *)sc.fpstate,
- IS_ENABLED(CONFIG_X86_32));
+ return fpu__restore_sig((void __user *)sc.fpstate,
+ IS_ENABLED(CONFIG_X86_32));
}

static __always_inline int