[PATCH v3] ppc64: Avoid pt_regs struct definition

[PATCH v3] ppc64: Avoid pt_regs struct definition

[Khem Raj]

Remove pt_regs indirection and instead reference gp_regs directly, this
makes it portable across musl/glibc

Move the file to ppc64 subdir and leave ppc empty

Fixes
../qemu-6.2.0/linux-user/host/ppc64/../ppc/host-signal.h:16:32: error: incomplete definition of type 'struct pt_regs'
    return uc->uc_mcontext.regs->nip;
           ~~~~~~~~~~~~~~~~~~~~^

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Philippe Mathieu-Daudé <f4bug@amsat.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
---
v2: Drop ifdef __powerpc__
v3: Access go_regs directly and move the file to ppc64 dir

 linux-user/include/host/ppc/host-signal.h   | 38 --------------------
 linux-user/include/host/ppc64/host-signal.h | 39 ++++++++++++++++++++-
 2 files changed, 38 insertions(+), 39 deletions(-)
 delete mode 100644 linux-user/include/host/ppc/host-signal.h

diff --git a/linux-user/include/host/ppc/host-signal.h b/linux-user/include/host/ppc/host-signal.h
deleted file mode 100644
index b80384d135..0000000000
--- a/linux-user/include/host/ppc/host-signal.h
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
- * host-signal.h: signal info dependent on the host architecture
- *
- * Copyright (c) 2003-2005 Fabrice Bellard
- * Copyright (c) 2021 Linaro Limited
- *
- * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
- * See the COPYING file in the top-level directory.
- */
-
-#ifndef PPC_HOST_SIGNAL_H
-#define PPC_HOST_SIGNAL_H
-
-/* The third argument to a SA_SIGINFO handler is ucontext_t. */
-typedef ucontext_t host_sigcontext;
-
-static inline uintptr_t host_signal_pc(host_sigcontext *uc)
-{
-    return uc->uc_mcontext.regs->nip;
-}
-
-static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc)
-{
-    uc->uc_mcontext.regs->nip = pc;
-}
-
-static inline void *host_signal_mask(host_sigcontext *uc)
-{
-    return &uc->uc_sigmask;
-}
-
-static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc)
-{
-    return uc->uc_mcontext.regs->trap != 0x400
-        && (uc->uc_mcontext.regs->dsisr & 0x02000000);
-}
-
-#endif
diff --git a/linux-user/include/host/ppc64/host-signal.h b/linux-user/include/host/ppc64/host-signal.h
index a353c22a90..b46143c2f0 100644
--- a/linux-user/include/host/ppc64/host-signal.h
+++ b/linux-user/include/host/ppc64/host-signal.h
@@ -1 +1,38 @@
-#include "../ppc/host-signal.h"
+/*
+ * host-signal.h: signal info dependent on the host architecture
+ *
+ * Copyright (c) 2003-2005 Fabrice Bellard
+ * Copyright (c) 2021 Linaro Limited
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef PPC_HOST_SIGNAL_H
+#define PPC_HOST_SIGNAL_H
+
+/* The third argument to a SA_SIGINFO handler is ucontext_t. */
+typedef ucontext_t host_sigcontext;
+
+static inline uintptr_t host_signal_pc(host_sigcontext *uc)
+{
+    return uc->uc_mcontext.gp_regs[32];
+}
+
+static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc)
+{
+    uc->uc_mcontext.gp_regs[32] = pc;
+}
+
+static inline void *host_signal_mask(host_sigcontext *uc)
+{
+    return &uc->uc_sigmask;
+}
+
+static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc)
+{
+    return uc->uc_mcontext.gp_regs[40] != 0x400
+        && (uc->uc_mcontext.gp_regs[42] & 0x02000000);
+}
+
+#endif
-- 
2.35.1

Re: [PATCH v3] ppc64: Avoid pt_regs struct definition

[Richard Henderson]

On 3/14/22 14:51, Khem Raj wrote:
> +static inline uintptr_t host_signal_pc(host_sigcontext *uc)
> +{
> +    return uc->uc_mcontext.gp_regs[32];
> +}
> +
> +static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc)
> +{
> +    uc->uc_mcontext.gp_regs[32] = pc;
> +}
> +
> +static inline void *host_signal_mask(host_sigcontext *uc)
> +{
> +    return &uc->uc_sigmask;
> +}
> +
> +static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc)
> +{
> +    return uc->uc_mcontext.gp_regs[40] != 0x400
> +        && (uc->uc_mcontext.gp_regs[42] & 0x02000000);
> +}

Oh, dear.

I didn't realize that the symbolic constants are also in <asm/ptrace.h>. We really don't 
want magic numbers.  We'll have to have the include and use PT_NIP, PT_TRAP, PT_DSISR.


r~

Re: [PATCH v3] ppc64: Avoid pt_regs struct definition

[Khem Raj]

On Mon, Mar 14, 2022 at 5:13 PM Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> On 3/14/22 14:51, Khem Raj wrote:
> > +static inline uintptr_t host_signal_pc(host_sigcontext *uc)
> > +{
> > +    return uc->uc_mcontext.gp_regs[32];
> > +}
> > +
> > +static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc)
> > +{
> > +    uc->uc_mcontext.gp_regs[32] = pc;
> > +}
> > +
> > +static inline void *host_signal_mask(host_sigcontext *uc)
> > +{
> > +    return &uc->uc_sigmask;
> > +}
> > +
> > +static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc)
> > +{
> > +    return uc->uc_mcontext.gp_regs[40] != 0x400
> > +        && (uc->uc_mcontext.gp_regs[42] & 0x02000000);
> > +}
>
> Oh, dear.
>
> I didn't realize that the symbolic constants are also in <asm/ptrace.h>. We really don't
> want magic numbers.  We'll have to have the include and use PT_NIP, PT_TRAP, PT_DSISR.
>

yeah :) removing asm/ptrace.h sounded lucrative but it does make it
cryptic. I will send v4 soon.

>
> r~