linux-user/host/arm: Populate host_signal.h

Split host_signal_pc and host_signal_write out of user-exec.c.
Drop the *BSD code, to be re-created under bsd-user/ later.

Reviewed-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

1 files changed, 30 insertions, 1 deletions

diff --git a/linux-user/host/arm/host-signal.h b/linux-user/host/arm/host-signal.h
index f4b4d65..efb165c 100644
--- a/linux-user/host/arm/host-signal.h
+++ b/linux-user/host/arm/host-signal.h
@@ -1 +1,30 @@
-#define HOST_SIGNAL_PLACEHOLDER
+/*
+ * 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 ARM_HOST_SIGNAL_H
+#define ARM_HOST_SIGNAL_H
+
+static inline uintptr_t host_signal_pc(ucontext_t *uc)
+{
+    return uc->uc_mcontext.arm_pc;
+}
+
+static inline bool host_signal_write(siginfo_t *info, ucontext_t *uc)
+{
+    /*
+     * In the FSR, bit 11 is WnR, assuming a v6 or
+     * later processor.  On v5 we will always report
+     * this as a read, which will fail later.
+     */
+    uint32_t fsr = uc->uc_mcontext.error_code;
+    return extract32(fsr, 11, 1);
+}
+
+#endif