o) Add COMPAT_FREEBSD32 support for MIPS kernels using the n64 ABI with userlands

   using the o32 ABI.  This mostly follows nwhitehorn's lead in implementing
   COMPAT_FREEBSD32 on powerpc64.
o) Add a new type to the freebsd32 compat layer, time32_t, which is time_t in the
   32-bit ABI being used.  Since the MIPS port is relatively-new, even the 32-bit
   ABIs use a 64-bit time_t.
o) Because time{spec,val}32 has the same size and layout as time{spec,val} on MIPS
   with 32-bit compatibility, then, disable some code which assumes otherwise
   wrongly when built for MIPS.  A more general macro to check in this case would
   seem like a good idea eventually.  If someone adds support for using n32
   userland with n64 kernels on MIPS, then they will have to add a variety of
   flags related to each piece of the ABI that can vary.  That's probably the
   right time to generalize further.
o) Add MIPS to the list of architectures which use PAD64_REQUIRED in the
   freebsd32 compat code.  Probably this should be generalized at some point.

Reviewed by:	gonzo

8 files changed, 98 insertions, 2 deletions

diff --git a/sys/mips/include/elf.h b/sys/mips/include/elf.h
index 39efeee..1c3d44d 100644
--- a/sys/mips/include/elf.h
+++ b/sys/mips/include/elf.h
@@ -52,6 +52,9 @@
 #include <sys/elf_generic.h>
 
 #define	ELF_ARCH	EM_MIPS
+#if __ELF_WORD_SIZE == 32
+#define	ELF_ARCH32	EM_MIPS
+#endif
 #define	ELF_MACHINE_OK(x) ((x) == EM_MIPS || (x) == EM_MIPS_RS4_BE)
 
 /* Architecture dependent Segment types - p_type */
diff --git a/sys/mips/include/md_var.h b/sys/mips/include/md_var.h
index 6f65a0f..00ff95a 100644
--- a/sys/mips/include/md_var.h
+++ b/sys/mips/include/md_var.h
@@ -41,7 +41,11 @@
  */
 extern	long	Maxmem;
 extern	char	sigcode[];
-extern	int	szsigcode, szosigcode;
+extern	int	szsigcode;
+#if defined(__mips_n32) || defined(__mips_n64)
+extern	char	sigcode32[];
+extern	int	szsigcode32;
+#endif
 extern	uint32_t *vm_page_dump;
 extern	int vm_page_dump_size;
 
diff --git a/sys/mips/include/param.h b/sys/mips/include/param.h
index 608d802..bd6d800 100644
--- a/sys/mips/include/param.h
+++ b/sys/mips/include/param.h
@@ -60,6 +60,9 @@
 #if _BYTE_ORDER == _BIG_ENDIAN
 #ifdef __mips_n64
 #define	MACHINE_ARCH	"mips64eb"
+#ifndef	MACHINE_ARCH32
+#define	MACHINE_ARCH32	"mipseb"
+#endif
 #elif defined(__mips_n32)
 #define	MACHINE_ARCH	"mipsn32eb"
 #else
@@ -68,6 +71,9 @@
 #else
 #ifdef __mips_n64
 #define	MACHINE_ARCH	"mips64el"
+#ifndef	MACHINE_ARCH32
+#define	MACHINE_ARCH32	"mipsel"
+#endif
 #elif defined(__mips_n32)
 #define	MACHINE_ARCH	"mipsn32el"
 #else
diff --git a/sys/mips/include/proc.h b/sys/mips/include/proc.h
index beba9167..42d08d9 100644
--- a/sys/mips/include/proc.h
+++ b/sys/mips/include/proc.h
@@ -96,6 +96,7 @@ struct syscall_args {
 
 #ifdef __mips_n64
 #define	KINFO_PROC_SIZE 1088
+#define	KINFO_PROC32_SIZE 816
 #else
 #define	KINFO_PROC_SIZE 816
 #endif
diff --git a/sys/mips/include/reg.h b/sys/mips/include/reg.h
index 6510db6..c240506 100644
--- a/sys/mips/include/reg.h
+++ b/sys/mips/include/reg.h
@@ -42,6 +42,10 @@
 #ifndef _MACHINE_REG_H_
 #define	_MACHINE_REG_H_
 
+#if defined(_KERNEL) && !defined(KLD_MODULE) && !defined(_STANDALONE)
+#include "opt_compat.h"
+#endif
+
 /*
  * Location of the users' stored registers relative to ZERO.
  * must be visible to assembly code.
@@ -66,6 +70,21 @@ struct dbreg {
 	unsigned long junk;
 };
 
+#ifdef COMPAT_FREEBSD32
+/* Must match struct trapframe */
+struct reg32 {
+	uint32_t r_regs[NUMSAVEREGS];
+};
+
+struct fpreg32 {
+	int32_t r_regs[NUMFPREGS];
+};
+
+struct dbreg32 {
+	uint32_t junk;
+};
+#endif
+
 #ifdef _KERNEL
 int	fill_fpregs(struct thread *, struct fpreg *);
 int	fill_regs(struct thread *, struct reg *);
@@ -75,4 +94,16 @@ int	fill_dbregs(struct thread *, struct dbreg *);
 int	set_dbregs(struct thread *, struct dbreg *);
 #endif
 
+#ifdef COMPAT_FREEBSD32
+struct image_params;
+
+int	fill_regs32(struct thread *, struct reg32 *);
+int	set_regs32(struct thread *, struct reg32 *);
+int	fill_fpregs32(struct thread *, struct fpreg32 *);
+int	set_fpregs32(struct thread *, struct fpreg32 *);
+
+#define	fill_dbregs32(td, reg)	0
+#define	set_dbregs32(td, reg)	0
+#endif
+
 #endif /* !_MACHINE_REG_H_ */
diff --git a/sys/mips/include/sigframe.h b/sys/mips/include/sigframe.h
index 6919882..69c7c02 100644
--- a/sys/mips/include/sigframe.h
+++ b/sys/mips/include/sigframe.h
@@ -32,6 +32,10 @@
 #ifndef _MACHINE_SIGFRAME_H_
 #define	_MACHINE_SIGFRAME_H_
 
+#if defined(_KERNEL) && !defined(KLD_MODULE) && !defined(_STANDALONE)
+#include "opt_compat.h"
+#endif
+
 /*
  * WARNING: code in locore.s assumes the layout shown for sf_signum
  * thru sf_addr so... don't alter them!
@@ -46,4 +50,18 @@ struct sigframe {
 	unsigned long	__spare__[2];
 };
 
+#if (defined(__mips_n32) || defined(__mips_n64)) && defined(COMPAT_FREEBSD32)
+#include <compat/freebsd32/freebsd32_signal.h>
+
+struct sigframe32 {
+	int32_t		sf_signum;
+	int32_t		sf_siginfo;	/* code or pointer to sf_si */
+	int32_t		sf_ucontext;	/* points to sf_uc */
+	int32_t		sf_addr;	/* undocumented 4th arg */
+	ucontext32_t	sf_uc;		/* = *sf_ucontext */
+	struct siginfo32	sf_si;	/* = *sf_siginfo (SA_SIGINFO case) */
+	uint32_t	__spare__[2];
+};
+#endif
+
 #endif /* !_MACHINE_SIGFRAME_H_ */
diff --git a/sys/mips/include/ucontext.h b/sys/mips/include/ucontext.h
index 72f07b4..aafd1dc 100644
--- a/sys/mips/include/ucontext.h
+++ b/sys/mips/include/ucontext.h
@@ -39,6 +39,10 @@
 
 #ifndef _LOCORE
 
+#if defined(_KERNEL) && !defined(KLD_MODULE) && !defined(_STANDALONE)
+#include "opt_compat.h"
+#endif
+
 typedef struct	__mcontext {
 	/*
 	 * These fields must match the corresponding fields in struct 
@@ -56,6 +60,32 @@ typedef struct	__mcontext {
 	void		*mc_tls;	/* pointer to TLS area */
 	int		__spare__[8];	/* XXX reserved */ 
 } mcontext_t;
+
+#if (defined(__mips_n32) || defined(__mips_n64)) && defined(COMPAT_FREEBSD32)
+#include <compat/freebsd32/freebsd32_signal.h>
+
+typedef struct __mcontext32 {
+	int		mc_onstack;
+	int32_t		mc_pc;
+	int32_t		mc_regs[32];
+	int32_t		sr;
+	int32_t		mullo, mulhi;
+	int		mc_fpused;
+	int32_t		mc_fpregs[33];
+	int32_t		mc_fpc_eir;
+	void		*mc_tls;
+	int		__spare__[8];
+} mcontext32_t;
+
+typedef struct __ucontext32 {
+	sigset_t		uc_sigmask;
+	mcontext32_t		uc_mcontext;
+	uint32_t		uc_link;
+	struct sigaltstack32    uc_stack;
+	uint32_t		uc_flags;
+	uint32_t		__spare__[4];
+} ucontext32_t;
+#endif
 #endif
 
 #ifndef SZREG
diff --git a/sys/mips/include/vmparam.h b/sys/mips/include/vmparam.h
index 4a702f5..aa0a5d7 100644
--- a/sys/mips/include/vmparam.h
+++ b/sys/mips/include/vmparam.h
@@ -96,7 +96,10 @@
  * offset is calculated.
  */
 #define	USRSTACK		(VM_MAXUSER_ADDRESS - PAGE_SIZE)
- 
+#ifdef __mips_n64
+#define	FREEBSD32_USRSTACK	(((vm_offset_t)0x80000000) - PAGE_SIZE)
+#endif
+
 /*
  * Only one memory domain.
  */