Actually build strace for RISC-V

It turns out the other port wasn't actually sufficient to do anything
with the strace port, it was just enough to get a RISC-V port built
with no actual support.

Makefile.am

@@ -155,6 +155,12 @@ EXTRA_DIST =				\
 	linux/powerpc/syscallent1.h	\
 	linux/ptp_clock.h		\
 	linux/reboot.h			\
+	linux/riscv/errnoent1.h		\
+	linux/riscv/ioctlent.h.in	\
+	linux/riscv/ioctlent1.h		\
+	linux/riscv/signalent1.h	\
+	linux/riscv/syscallent.h	\
+	linux/riscv/syscallent1.h	\
 	linux/s390/ioctlent.h.in	\
 	linux/s390/syscallent.h		\
 	linux/s390x/ioctlent.h.in	\

Makefile.in

@@ -643,6 +643,12 @@ EXTRA_DIST = \
 	linux/powerpc/syscallent1.h	\
 	linux/ptp_clock.h		\
 	linux/reboot.h			\
+	linux/riscv/errnoent1.h		\
+	linux/riscv/ioctlent.h.in	\
+	linux/riscv/ioctlent1.h		\
+	linux/riscv/signalent1.h	\
+	linux/riscv/syscallent.h	\
+	linux/riscv/syscallent1.h	\
 	linux/s390/ioctlent.h.in	\
 	linux/s390/syscallent.h		\
 	linux/s390x/ioctlent.h.in	\

config.h.in

@@ -1686,6 +1686,9 @@
 /* Define as the return type of signal handlers (`int' or `void'). */
 #undef RETSIGTYPE
 
+/* Define for the RISC-V architecture */
+#undef RISCV
+
 /* Define for the S390 architecture. */
 #undef S390
 

defs.h

@@ -611,6 +611,7 @@ extern void call_summary(FILE *);
  || defined(X86_64) || defined(X32) \
  || defined(AARCH64) \
  || defined(ARM) \
+ || defined(RISCV) \
  || defined(SPARC) || defined(SPARC64) \
  || defined(TILE) \
  || defined(OR1K) \

linux/riscv/errnoent1.h

@@ -1,2 +1,2 @@
-/* tilegx32/tilepro */
+/* RISC-V rv32 and rv64 */
 #include "../errnoent.h"

linux/riscv/ioctlent1.h

@@ -1,2 +1,2 @@
-/* tilegx32/tilepro */
+/* RISC-V rv32 and rv64 */
 #include "ioctlent.h"

linux/riscv/signalent1.h

@@ -1,2 +1,2 @@
-/* tilegx32/tilepro */
+/* RISC-V rv32 and rv64 */
 #include "../signalent.h"

process.c

@@ -319,7 +319,7 @@ extern void print_user_desc(struct tcb *, long);
 # define ARG_PTID	2
 # define ARG_CTID	((current_personality != 1) ? 3 : 4)
 # define ARG_TLS	((current_personality != 1) ? 4 : 3)
-#elif defined ALPHA || defined TILE || defined OR1K
+#elif defined ALPHA || defined TILE || defined OR1K || defined RISCV
 # define ARG_FLAGS	0
 # define ARG_STACK	1
 # define ARG_PTID	2
@@ -1096,6 +1096,10 @@ const struct xlat struct_user_offsets[] = {
 	{ PT_IEEE_IP,		"ieee_exception_ip"			},
 #elif defined(SPARC)
 	/* XXX No support for these offsets yet. */
+#elif defined(RISCV)
+        /* FIXME: RISCV: Figure these out, maybe they're just a
+         * ucontext offset?  I certainly hope so... */
+	/* XXX No support for these offsets yet. */
 #elif defined(HPPA)
 	/* XXX No support for these offsets yet. */
 #elif defined(POWERPC)
@@ -2095,6 +2099,9 @@ const struct xlat struct_user_offsets[] = {
 	/* nothing */
 #elif defined(ARC)
 	/* nothing */
+#elif defined(RISCV)
+        /* FIXME: RISCV: Is there really nothing here? */
+        /* nothing */
 #endif
 	XLAT_END
 };

signal.c

@@ -938,6 +938,9 @@ sys_sigreturn(struct tcb *tcp)
 	/* Xtensa only has rt_sys_sigreturn */
 #elif defined(ARC)
 	/* ARC syscall ABI only supports rt_sys_sigreturn */
+#elif defined(RISCV)
+        /* FIXME: RISCV: I think this is true? */
+        /* RISC-V only has rt_sys_sigreturn */
 #else
 # warning No sys_sigreturn() for this architecture
 # warning         (no problem, just a reminder :-)

syscall.c

@@ -81,6 +81,10 @@
 # include <asm/ptrace.h>
 #endif
 
+#if defined(RISCV)
+# include <asm/ptrace.h>
+#endif
+
 #ifndef NSIG
 # warning: NSIG is not defined, using 32
 # define NSIG 32
@@ -782,6 +786,9 @@ static long xtensa_a2;
 # elif defined(ARC)
 static struct user_regs_struct arc_regs;
 # define ARCH_REGS_FOR_GETREGSET arc_regs
+#elif defined(RISCV)
+#define ARCH_REGS_FOR_GETREGSET riscv_regs
+static struct user_regs_struct riscv_regs;
 #endif
 
 void
@@ -924,6 +931,12 @@ print_pc(struct tcb *tcp)
 	tprintf("[%08lx] ", pc);
 #elif defined(ARC)
 	tprintf("[%08lx] ", arc_regs.efa);
+#elif defined(RISCV)
+# ifdef _LP64
+        tprintf("[%016lx] ", riscv_regs.pc);
+# else
+        tprintf("[%08lx] ",  riscv_regs.pc);
+# endif
 #endif /* architecture */
 }
 
@@ -1021,6 +1034,7 @@ static void get_regset(pid_t pid)
   || defined(METAG) \
   || defined(OR1K) \
   || defined(ARC)
+  || defined(RISCV)
 	static struct iovec io = {
 		.iov_base = &ARCH_REGS_FOR_GETREGSET,
 		.iov_len = sizeof(ARCH_REGS_FOR_GETREGSET)
@@ -1046,7 +1060,7 @@ void
 get_regs(pid_t pid)
 {
 /* PTRACE_GETREGSET only */
-# if defined(METAG) || defined(OR1K) || defined(X32) || defined(AARCH64) || defined(ARC)
+# if defined(METAG) || defined(OR1K) || defined(X32) || defined(AARCH64) || defined(ARC) || defined (RISCV)
 	get_regset(pid);
 
 /* PTRACE_GETREGS only */
@@ -1556,6 +1570,8 @@ get_scno(struct tcb *tcp)
 		return -1;
 # elif defined(ARC)
 	scno = arc_regs.scratch.r8;
+#elif defined(RISCV)
+        scno = riscv_regs.a7;
 #endif
 
 	tcp->scno = scno;
@@ -1950,6 +1966,13 @@ get_syscall_args(struct tcb *tcp)
 	for (i = 0; i < nargs; ++i)
 		tcp->u_arg[i] = *arc_args--;
 
+#elif defined(RISCV)
+        tcp->u_arg[0] = riscv_regs.a0;
+        tcp->u_arg[1] = riscv_regs.a1;
+        tcp->u_arg[2] = riscv_regs.a2;
+        tcp->u_arg[3] = riscv_regs.a3;
+        tcp->u_arg[4] = riscv_regs.a4;
+        tcp->u_arg[5] = riscv_regs.a5;
 #else /* Other architecture (32bits specific) */
 	for (i = 0; i < nargs; ++i)
 		if (upeek(tcp->pid, i*4, &tcp->u_arg[i]) < 0)
@@ -2156,6 +2179,8 @@ get_syscall_result(struct tcb *tcp)
 	if (upeek(tcp->pid, REG_A_BASE + 2, &xtensa_a2) < 0)
 		return -1;
 #elif defined(ARC)
+#elif defined(RISCV)
+        /* FIXME: Is this true?  I think in the new ABI it is? */
 	/* already done by get_regs */
 #endif
 	return 1;
@@ -2470,6 +2495,13 @@ get_error(struct tcb *tcp)
 	else {
 		tcp->u_rval = arc_regs.scratch.r0;
 	}
+#elif defined(RISCV)
+        if (check_errno && is_negated_errno(riscv_regs.a0)) {
+            tcp->u_rval = -1;
+            u_error = -riscv_regs.a0;
+        } else {
+            tcp->u_rval = riscv_regs.a0;
+        }
 #endif
 	tcp->u_error = u_error;
 }

util.c

@@ -1457,6 +1457,9 @@ change_syscall(struct tcb *tcp, arg_setup_state *state, int new)
 #elif defined(ARC)
 	/* setbpt/clearbpt never used: */
 	/* ARC only supported since 3.9 */
+#elif defined(RISCV)
+	/* setbpt/clearbpt never used: */
+	/* RISC-V CPUs are only supported since about linux-3.14 */
 #else
 #warning Do not know how to handle change_syscall for this architecture
 #endif /* architecture */