RISC-V: Add support for rv32 userspace via COMPAT

The RISC-V port supports the rv32i and rv64i base ISAs, but provides no
mechanism to run 32-bit userspace on 64-bit systems.  This adds that
support, via the COMPAT framework.  As the RISC-V ISAs (and uABIs) were
developed concurrently, the resulting compat support is mostly generic.

This includes a handful of cleanups to the generic compat infrastructure
to more cleanly support RISC-V, followed by the RISC-V implementation.

* palmer/riscv-compat:
  riscv: compat: Add COMPAT Kbuild skeletal support
  riscv: compat: ptrace: Add compat_arch_ptrace implement
  riscv: compat: signal: Add rt_frame implementation
  riscv: compat: vdso: Add setup additional pages implementation
  riscv: compat: vdso: Add COMPAT_VDSO base code implementation
  riscv: compat: Add hw capability check for elf
  riscv: compat: Add elf.h implementation
  riscv: compat: process: Add UXL_32 support in start_thread
  riscv: compat: syscall: Add entry.S implementation
  riscv: compat: syscall: Add compat_sys_call_table implementation
  riscv: compat: Support TASK_SIZE for compat mode
  riscv: compat: Add basic compat data type implementation
  riscv: Fixup difference with defconfig
  syscalls: compat: Fix the missing part for __SYSCALL_COMPAT
  asm-generic: compat: Cleanup duplicate definitions
  fs: stat: compat: Add __ARCH_WANT_COMPAT_STAT
  arch: Add SYSVIPC_COMPAT for all architectures
  compat: consolidate the compat_flock{,64} definition
  uapi: always define F_GETLK64/F_SETLK64/F_SETLKW64 in fcntl.h
  uapi: simplify __ARCH_FLOCK{,64}_PAD a little

2 files changed, 11 insertions, 16 deletions

diff --git a/include/uapi/asm-generic/fcntl.h b/include/uapi/asm-generic/fcntl.h
index ecd0f5bdfc1d..f13d37b60775 100644
--- a/include/uapi/asm-generic/fcntl.h
+++ b/include/uapi/asm-generic/fcntl.h
@@ -116,13 +116,13 @@
 #define F_GETSIG	11	/* for sockets. */
 #endif
 
-#ifndef CONFIG_64BIT
+#if __BITS_PER_LONG == 32 || defined(__KERNEL__)
 #ifndef F_GETLK64
 #define F_GETLK64	12	/*  using 'struct flock64' */
 #define F_SETLK64	13
 #define F_SETLKW64	14
 #endif
-#endif
+#endif /* __BITS_PER_LONG == 32 || defined(__KERNEL__) */
 
 #ifndef F_SETOWN_EX
 #define F_SETOWN_EX	15
@@ -192,25 +192,19 @@ struct f_owner_ex {
 
 #define F_LINUX_SPECIFIC_BASE	1024
 
-#ifndef HAVE_ARCH_STRUCT_FLOCK
-#ifndef __ARCH_FLOCK_PAD
-#define __ARCH_FLOCK_PAD
-#endif
-
 struct flock {
 	short	l_type;
 	short	l_whence;
 	__kernel_off_t	l_start;
 	__kernel_off_t	l_len;
 	__kernel_pid_t	l_pid;
-	__ARCH_FLOCK_PAD
-};
+#ifdef	__ARCH_FLOCK_EXTRA_SYSID
+	__ARCH_FLOCK_EXTRA_SYSID
 #endif
-
-#ifndef HAVE_ARCH_STRUCT_FLOCK64
-#ifndef __ARCH_FLOCK64_PAD
-#define __ARCH_FLOCK64_PAD
+#ifdef	__ARCH_FLOCK_PAD
+	__ARCH_FLOCK_PAD
 #endif
+};
 
 struct flock64 {
 	short  l_type;
@@ -218,8 +212,9 @@ struct flock64 {
 	__kernel_loff_t l_start;
 	__kernel_loff_t l_len;
 	__kernel_pid_t  l_pid;
+#ifdef	__ARCH_FLOCK64_PAD
 	__ARCH_FLOCK64_PAD
-};
 #endif
+};
 
 #endif /* _ASM_GENERIC_FCNTL_H */
diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h
index 1c48b0ae3ba3..45fa180cc56a 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -383,7 +383,7 @@ __SYSCALL(__NR_syslog, sys_syslog)
 
 /* kernel/ptrace.c */
 #define __NR_ptrace 117
-__SYSCALL(__NR_ptrace, sys_ptrace)
+__SC_COMP(__NR_ptrace, sys_ptrace, compat_sys_ptrace)
 
 /* kernel/sched/core.c */
 #define __NR_sched_setparam 118
@@ -779,7 +779,7 @@ __SYSCALL(__NR_rseq, sys_rseq)
 #define __NR_kexec_file_load 294
 __SYSCALL(__NR_kexec_file_load,     sys_kexec_file_load)
 /* 295 through 402 are unassigned to sync up with generic numbers, don't use */
-#if __BITS_PER_LONG == 32
+#if defined(__SYSCALL_COMPAT) || __BITS_PER_LONG == 32
 #define __NR_clock_gettime64 403
 __SYSCALL(__NR_clock_gettime64, sys_clock_gettime)
 #define __NR_clock_settime64 404