Jumbo-commit to enhance 32 bit application support on 64 bit kernels.

This is good enough to be able to run a RELENG_4 gdb binary against
a RELENG_4 application, along with various other tools (eg: 4.x gcore).
We use this at work.

ia32_reg.[ch]: handle the 32 bit register file format, used by ptrace,
	procfs and core dumps.
procfs_*regs.c: vary the format of proc/XXX/*regs depending on the client
	and target application.
procfs_map.c: Don't print a 64 bit value to 32 bit consumers, or their
	sscanf fails.  They expect an unsigned long.
imgact_elf.c: produce a valid 32 bit coredump for 32 bit apps.
sys_process.c: handle 32 bit consumers debugging 32 bit targets.  Note
	that 64 bit consumers can still debug 32 bit targets.

IA64 has got stubs for ia32_reg.c.

Known limitations: a 5.x/6.x gdb uses get/setcontext(), which isn't
implemented in the 32/64 wrapper yet.  We also make a tiny patch to
gdb pacify it over conflicting formats of ld-elf.so.1.

Approved by:	re

1 files changed, 141 insertions, 0 deletions

diff --git a/sys/compat/ia32/ia32_reg.h b/sys/compat/ia32/ia32_reg.h
new file mode 100644
index 0000000..5a9cdf2
--- /dev/null
+++ b/sys/compat/ia32/ia32_reg.h
@@ -0,0 +1,141 @@
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * William Jolitz.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ *	from: @(#)reg.h	5.5 (Berkeley) 1/18/91
+ * $FreeBSD$
+ */
+
+#ifndef _COMPAT_IA32_IA32_REG_H_
+#define	_COMPAT_IA32_IA32_REG_H_
+
+/*
+ * Register set accessible via /proc/$pid/regs and PT_{SET,GET}REGS.
+ */
+struct reg32 {
+	unsigned int	r_fs;
+	unsigned int	r_es;
+	unsigned int	r_ds;
+	unsigned int	r_edi;
+	unsigned int	r_esi;
+	unsigned int	r_ebp;
+	unsigned int	r_isp;
+	unsigned int	r_ebx;
+	unsigned int	r_edx;
+	unsigned int	r_ecx;
+	unsigned int	r_eax;
+	unsigned int	r_trapno;
+	unsigned int	r_err;
+	unsigned int	r_eip;
+	unsigned int	r_cs;
+	unsigned int	r_eflags;
+	unsigned int	r_esp;
+	unsigned int	r_ss;
+	unsigned int	r_gs;
+};
+
+/*
+ * Register set accessible via /proc/$pid/fpregs.
+ */
+struct fpreg32 {
+	unsigned int	fpr_env[7];
+	unsigned char	fpr_acc[8][10];
+	unsigned int	fpr_ex_sw;
+	unsigned char	fpr_pad[64];
+};
+
+/*
+ * Register set accessible via /proc/$pid/dbregs.
+ */
+struct dbreg32 {
+	unsigned int  dr[8];	/* debug registers */
+};
+
+/* Environment information of floating point unit */
+struct env87 {
+	int	en_cw;		/* control word (16bits) */
+	int	en_sw;		/* status word (16bits) */
+	int	en_tw;		/* tag word (16bits) */
+	int	en_fip;		/* floating point instruction pointer */
+	u_short	en_fcs;		/* floating code segment selector */
+	u_short	en_opcode;	/* opcode last executed (11 bits ) */
+	int	en_foo;		/* floating operand offset */
+	int	en_fos;		/* floating operand segment selector */
+};
+
+#ifdef __ia64__
+/* Layout of an x87 fpu register (amd64 gets this elsewhere) */
+struct fpacc87 {
+	u_char  fp_bytes[10];
+};
+#endif
+
+/* Floating point context */
+struct save87 {
+	struct	env87 sv_env;	/* floating point control/status */
+	struct	fpacc87 sv_ac[8];	/* accumulator contents, 0-7 */
+	u_char	sv_pad0[4];	/* padding for (now unused) saved status word */
+	u_char	sv_pad[64];	/* padding; used by emulators */
+};
+
+
+/*
+ * Alternative layouts for <sys/procfs.h>
+ * Used in core dumps, the reason for this file existing.
+ */
+struct prstatus32 {
+	int	pr_version;
+	u_int	pr_statussz;
+	u_int	pr_gregsetsz;
+	u_int	pr_fpregsetsz;
+	int	pr_osreldate;
+	int	pr_cursig;
+	pid_t	pr_pid;
+	struct reg32 pr_reg;
+};
+
+struct prpsinfo32 {
+	int	pr_version;
+	u_int	pr_psinfosz;
+	char	pr_fname[PRFNAMESZ+1];
+	char	pr_psargs[PRARGSZ+1];
+};
+
+/*
+ * Wrappers and converters.
+ */
+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 *);
+int	fill_dbregs32(struct thread *, struct dbreg32 *);
+int	set_dbregs32(struct thread *, struct dbreg32 *);
+
+#endif /* !_COMPAT_IA32_IA32_REG_H_ */