Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/arch/ppc64/kernel/traps.c b/arch/ppc64/kernel/traps.c
new file mode 100644
index 0000000..10fc61f
--- /dev/null
+++ b/arch/ppc64/kernel/traps.c
@@ -0,0 +1,565 @@
+/*
+ *  linux/arch/ppc64/kernel/traps.c
+ *
+ *  Copyright (C) 1995-1996  Gary Thomas (gdt@linuxppc.org)
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version
+ *  2 of the License, or (at your option) any later version.
+ *
+ *  Modified by Cort Dougan (cort@cs.nmt.edu)
+ *  and Paul Mackerras (paulus@cs.anu.edu.au)
+ */
+
+/*
+ * This file handles the architecture-dependent parts of hardware exceptions
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include <linux/user.h>
+#include <linux/a.out.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <asm/kdebug.h>
+
+#include <asm/pgtable.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/processor.h>
+#include <asm/ppcdebug.h>
+#include <asm/rtas.h>
+#include <asm/systemcfg.h>
+#include <asm/machdep.h>
+#include <asm/pmc.h>
+
+#ifdef CONFIG_DEBUGGER
+int (*__debugger)(struct pt_regs *regs);
+int (*__debugger_ipi)(struct pt_regs *regs);
+int (*__debugger_bpt)(struct pt_regs *regs);
+int (*__debugger_sstep)(struct pt_regs *regs);
+int (*__debugger_iabr_match)(struct pt_regs *regs);
+int (*__debugger_dabr_match)(struct pt_regs *regs);
+int (*__debugger_fault_handler)(struct pt_regs *regs);
+
+EXPORT_SYMBOL(__debugger);
+EXPORT_SYMBOL(__debugger_ipi);
+EXPORT_SYMBOL(__debugger_bpt);
+EXPORT_SYMBOL(__debugger_sstep);
+EXPORT_SYMBOL(__debugger_iabr_match);
+EXPORT_SYMBOL(__debugger_dabr_match);
+EXPORT_SYMBOL(__debugger_fault_handler);
+#endif
+
+struct notifier_block *ppc64_die_chain;
+static DEFINE_SPINLOCK(die_notifier_lock);
+
+int register_die_notifier(struct notifier_block *nb)
+{
+	int err = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&die_notifier_lock, flags);
+	err = notifier_chain_register(&ppc64_die_chain, nb);
+	spin_unlock_irqrestore(&die_notifier_lock, flags);
+	return err;
+}
+
+/*
+ * Trap & Exception support
+ */
+
+static DEFINE_SPINLOCK(die_lock);
+
+int die(const char *str, struct pt_regs *regs, long err)
+{
+	static int die_counter;
+	int nl = 0;
+
+	if (debugger(regs))
+		return 1;
+
+	console_verbose();
+	spin_lock_irq(&die_lock);
+	bust_spinlocks(1);
+	printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
+#ifdef CONFIG_PREEMPT
+	printk("PREEMPT ");
+	nl = 1;
+#endif
+#ifdef CONFIG_SMP
+	printk("SMP NR_CPUS=%d ", NR_CPUS);
+	nl = 1;
+#endif
+#ifdef CONFIG_DEBUG_PAGEALLOC
+	printk("DEBUG_PAGEALLOC ");
+	nl = 1;
+#endif
+#ifdef CONFIG_NUMA
+	printk("NUMA ");
+	nl = 1;
+#endif
+	switch(systemcfg->platform) {
+		case PLATFORM_PSERIES:
+			printk("PSERIES ");
+			nl = 1;
+			break;
+		case PLATFORM_PSERIES_LPAR:
+			printk("PSERIES LPAR ");
+			nl = 1;
+			break;
+		case PLATFORM_ISERIES_LPAR:
+			printk("ISERIES LPAR ");
+			nl = 1;
+			break;
+		case PLATFORM_POWERMAC:
+			printk("POWERMAC ");
+			nl = 1;
+			break;
+	}
+	if (nl)
+		printk("\n");
+	print_modules();
+	show_regs(regs);
+	bust_spinlocks(0);
+	spin_unlock_irq(&die_lock);
+
+	if (in_interrupt())
+		panic("Fatal exception in interrupt");
+
+	if (panic_on_oops) {
+		printk(KERN_EMERG "Fatal exception: panic in 5 seconds\n");
+		ssleep(5);
+		panic("Fatal exception");
+	}
+	do_exit(SIGSEGV);
+
+	return 0;
+}
+
+void _exception(int signr, struct pt_regs *regs, int code, unsigned long addr)
+{
+	siginfo_t info;
+
+	if (!user_mode(regs)) {
+		if (die("Exception in kernel mode", regs, signr))
+			return;
+	}
+
+	memset(&info, 0, sizeof(info));
+	info.si_signo = signr;
+	info.si_code = code;
+	info.si_addr = (void __user *) addr;
+	force_sig_info(signr, &info, current);
+}
+
+void system_reset_exception(struct pt_regs *regs)
+{
+	/* See if any machine dependent calls */
+	if (ppc_md.system_reset_exception)
+		ppc_md.system_reset_exception(regs);
+
+	die("System Reset", regs, 0);
+
+	/* Must die if the interrupt is not recoverable */
+	if (!(regs->msr & MSR_RI))
+		panic("Unrecoverable System Reset");
+
+	/* What should we do here? We could issue a shutdown or hard reset. */
+}
+
+void machine_check_exception(struct pt_regs *regs)
+{
+	int recover = 0;
+
+	/* See if any machine dependent calls */
+	if (ppc_md.machine_check_exception)
+		recover = ppc_md.machine_check_exception(regs);
+
+	if (recover)
+		return;
+
+	if (debugger_fault_handler(regs))
+		return;
+	die("Machine check", regs, 0);
+
+	/* Must die if the interrupt is not recoverable */
+	if (!(regs->msr & MSR_RI))
+		panic("Unrecoverable Machine check");
+}
+
+void unknown_exception(struct pt_regs *regs)
+{
+	printk("Bad trap at PC: %lx, SR: %lx, vector=%lx\n",
+	       regs->nip, regs->msr, regs->trap);
+
+	_exception(SIGTRAP, regs, 0, 0);
+}
+
+void instruction_breakpoint_exception(struct pt_regs *regs)
+{
+	if (notify_die(DIE_IABR_MATCH, "iabr_match", regs, 5,
+					5, SIGTRAP) == NOTIFY_STOP)
+		return;
+	if (debugger_iabr_match(regs))
+		return;
+	_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
+}
+
+void single_step_exception(struct pt_regs *regs)
+{
+	regs->msr &= ~MSR_SE;  /* Turn off 'trace' bit */
+
+	if (notify_die(DIE_SSTEP, "single_step", regs, 5,
+					5, SIGTRAP) == NOTIFY_STOP)
+		return;
+	if (debugger_sstep(regs))
+		return;
+
+	_exception(SIGTRAP, regs, TRAP_TRACE, regs->nip);
+}
+
+/*
+ * After we have successfully emulated an instruction, we have to
+ * check if the instruction was being single-stepped, and if so,
+ * pretend we got a single-step exception.  This was pointed out
+ * by Kumar Gala.  -- paulus
+ */
+static inline void emulate_single_step(struct pt_regs *regs)
+{
+	if (regs->msr & MSR_SE)
+		single_step_exception(regs);
+}
+
+static void parse_fpe(struct pt_regs *regs)
+{
+	int code = 0;
+	unsigned long fpscr;
+
+	flush_fp_to_thread(current);
+
+	fpscr = current->thread.fpscr;
+
+	/* Invalid operation */
+	if ((fpscr & FPSCR_VE) && (fpscr & FPSCR_VX))
+		code = FPE_FLTINV;
+
+	/* Overflow */
+	else if ((fpscr & FPSCR_OE) && (fpscr & FPSCR_OX))
+		code = FPE_FLTOVF;
+
+	/* Underflow */
+	else if ((fpscr & FPSCR_UE) && (fpscr & FPSCR_UX))
+		code = FPE_FLTUND;
+
+	/* Divide by zero */
+	else if ((fpscr & FPSCR_ZE) && (fpscr & FPSCR_ZX))
+		code = FPE_FLTDIV;
+
+	/* Inexact result */
+	else if ((fpscr & FPSCR_XE) && (fpscr & FPSCR_XX))
+		code = FPE_FLTRES;
+
+	_exception(SIGFPE, regs, code, regs->nip);
+}
+
+/*
+ * Illegal instruction emulation support.  Return non-zero if we can't
+ * emulate, or -EFAULT if the associated memory access caused an access
+ * fault.  Return zero on success.
+ */
+
+#define INST_MFSPR_PVR		0x7c1f42a6
+#define INST_MFSPR_PVR_MASK	0xfc1fffff
+
+#define INST_DCBA		0x7c0005ec
+#define INST_DCBA_MASK		0x7c0007fe
+
+#define INST_MCRXR		0x7c000400
+#define INST_MCRXR_MASK		0x7c0007fe
+
+static int emulate_instruction(struct pt_regs *regs)
+{
+	unsigned int instword;
+
+	if (!user_mode(regs))
+		return -EINVAL;
+
+	CHECK_FULL_REGS(regs);
+
+	if (get_user(instword, (unsigned int __user *)(regs->nip)))
+		return -EFAULT;
+
+	/* Emulate the mfspr rD, PVR. */
+	if ((instword & INST_MFSPR_PVR_MASK) == INST_MFSPR_PVR) {
+		unsigned int rd;
+
+		rd = (instword >> 21) & 0x1f;
+		regs->gpr[rd] = mfspr(SPRN_PVR);
+		return 0;
+	}
+
+	/* Emulating the dcba insn is just a no-op.  */
+	if ((instword & INST_DCBA_MASK) == INST_DCBA) {
+		static int warned;
+
+		if (!warned) {
+			printk(KERN_WARNING
+			       "process %d (%s) uses obsolete 'dcba' insn\n",
+			       current->pid, current->comm);
+			warned = 1;
+		}
+		return 0;
+	}
+
+	/* Emulate the mcrxr insn.  */
+	if ((instword & INST_MCRXR_MASK) == INST_MCRXR) {
+		static int warned;
+		unsigned int shift;
+
+		if (!warned) {
+			printk(KERN_WARNING
+			       "process %d (%s) uses obsolete 'mcrxr' insn\n",
+			       current->pid, current->comm);
+			warned = 1;
+		}
+
+		shift = (instword >> 21) & 0x1c;
+		regs->ccr &= ~(0xf0000000 >> shift);
+		regs->ccr |= (regs->xer & 0xf0000000) >> shift;
+		regs->xer &= ~0xf0000000;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+/*
+ * Look through the list of trap instructions that are used for BUG(),
+ * BUG_ON() and WARN_ON() and see if we hit one.  At this point we know
+ * that the exception was caused by a trap instruction of some kind.
+ * Returns 1 if we should continue (i.e. it was a WARN_ON) or 0
+ * otherwise.
+ */
+extern struct bug_entry __start___bug_table[], __stop___bug_table[];
+
+#ifndef CONFIG_MODULES
+#define module_find_bug(x)	NULL
+#endif
+
+struct bug_entry *find_bug(unsigned long bugaddr)
+{
+	struct bug_entry *bug;
+
+	for (bug = __start___bug_table; bug < __stop___bug_table; ++bug)
+		if (bugaddr == bug->bug_addr)
+			return bug;
+	return module_find_bug(bugaddr);
+}
+
+static int
+check_bug_trap(struct pt_regs *regs)
+{
+	struct bug_entry *bug;
+	unsigned long addr;
+
+	if (regs->msr & MSR_PR)
+		return 0;	/* not in kernel */
+	addr = regs->nip;	/* address of trap instruction */
+	if (addr < PAGE_OFFSET)
+		return 0;
+	bug = find_bug(regs->nip);
+	if (bug == NULL)
+		return 0;
+	if (bug->line & BUG_WARNING_TRAP) {
+		/* this is a WARN_ON rather than BUG/BUG_ON */
+		printk(KERN_ERR "Badness in %s at %s:%d\n",
+		       bug->function, bug->file,
+		      (unsigned int)bug->line & ~BUG_WARNING_TRAP);
+		show_stack(current, (void *)regs->gpr[1]);
+		return 1;
+	}
+	printk(KERN_CRIT "kernel BUG in %s at %s:%d!\n",
+	       bug->function, bug->file, (unsigned int)bug->line);
+	return 0;
+}
+
+void program_check_exception(struct pt_regs *regs)
+{
+	if (debugger_fault_handler(regs))
+		return;
+
+	if (regs->msr & 0x100000) {
+		/* IEEE FP exception */
+		parse_fpe(regs);
+	} else if (regs->msr & 0x20000) {
+		/* trap exception */
+
+		if (notify_die(DIE_BPT, "breakpoint", regs, 5,
+					5, SIGTRAP) == NOTIFY_STOP)
+			return;
+		if (debugger_bpt(regs))
+			return;
+
+		if (check_bug_trap(regs)) {
+			regs->nip += 4;
+			return;
+		}
+		_exception(SIGTRAP, regs, TRAP_BRKPT, regs->nip);
+
+	} else {
+		/* Privileged or illegal instruction; try to emulate it. */
+		switch (emulate_instruction(regs)) {
+		case 0:
+			regs->nip += 4;
+			emulate_single_step(regs);
+			break;
+
+		case -EFAULT:
+			_exception(SIGSEGV, regs, SEGV_MAPERR, regs->nip);
+			break;
+
+		default:
+			if (regs->msr & 0x40000)
+				/* priveleged */
+				_exception(SIGILL, regs, ILL_PRVOPC, regs->nip);
+			else
+				/* illegal */
+				_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+			break;
+		}
+	}
+}
+
+void kernel_fp_unavailable_exception(struct pt_regs *regs)
+{
+	printk(KERN_EMERG "Unrecoverable FP Unavailable Exception "
+			  "%lx at %lx\n", regs->trap, regs->nip);
+	die("Unrecoverable FP Unavailable Exception", regs, SIGABRT);
+}
+
+void altivec_unavailable_exception(struct pt_regs *regs)
+{
+#ifndef CONFIG_ALTIVEC
+	if (user_mode(regs)) {
+		/* A user program has executed an altivec instruction,
+		   but this kernel doesn't support altivec. */
+		_exception(SIGILL, regs, ILL_ILLOPC, regs->nip);
+		return;
+	}
+#endif
+	printk(KERN_EMERG "Unrecoverable VMX/Altivec Unavailable Exception "
+			  "%lx at %lx\n", regs->trap, regs->nip);
+	die("Unrecoverable VMX/Altivec Unavailable Exception", regs, SIGABRT);
+}
+
+extern perf_irq_t perf_irq;
+
+void performance_monitor_exception(struct pt_regs *regs)
+{
+	perf_irq(regs);
+}
+
+void alignment_exception(struct pt_regs *regs)
+{
+	int fixed;
+
+	fixed = fix_alignment(regs);
+
+	if (fixed == 1) {
+		regs->nip += 4;	/* skip over emulated instruction */
+		emulate_single_step(regs);
+		return;
+	}
+
+	/* Operand address was bad */	
+	if (fixed == -EFAULT) {
+		if (user_mode(regs)) {
+			_exception(SIGSEGV, regs, SEGV_MAPERR, regs->dar);
+		} else {
+			/* Search exception table */
+			bad_page_fault(regs, regs->dar, SIGSEGV);
+		}
+
+		return;
+	}
+
+	_exception(SIGBUS, regs, BUS_ADRALN, regs->nip);
+}
+
+#ifdef CONFIG_ALTIVEC
+void altivec_assist_exception(struct pt_regs *regs)
+{
+	int err;
+	siginfo_t info;
+
+	if (!user_mode(regs)) {
+		printk(KERN_EMERG "VMX/Altivec assist exception in kernel mode"
+		       " at %lx\n", regs->nip);
+		die("Kernel VMX/Altivec assist exception", regs, SIGILL);
+	}
+
+	flush_altivec_to_thread(current);
+
+	err = emulate_altivec(regs);
+	if (err == 0) {
+		regs->nip += 4;		/* skip emulated instruction */
+		emulate_single_step(regs);
+		return;
+	}
+
+	if (err == -EFAULT) {
+		/* got an error reading the instruction */
+		info.si_signo = SIGSEGV;
+		info.si_errno = 0;
+		info.si_code = SEGV_MAPERR;
+		info.si_addr = (void __user *) regs->nip;
+		force_sig_info(SIGSEGV, &info, current);
+	} else {
+		/* didn't recognize the instruction */
+		/* XXX quick hack for now: set the non-Java bit in the VSCR */
+		if (printk_ratelimit())
+			printk(KERN_ERR "Unrecognized altivec instruction "
+			       "in %s at %lx\n", current->comm, regs->nip);
+		current->thread.vscr.u[3] |= 0x10000;
+	}
+}
+#endif /* CONFIG_ALTIVEC */
+
+/*
+ * We enter here if we get an unrecoverable exception, that is, one
+ * that happened at a point where the RI (recoverable interrupt) bit
+ * in the MSR is 0.  This indicates that SRR0/1 are live, and that
+ * we therefore lost state by taking this exception.
+ */
+void unrecoverable_exception(struct pt_regs *regs)
+{
+	printk(KERN_EMERG "Unrecoverable exception %lx at %lx\n",
+	       regs->trap, regs->nip);
+	die("Unrecoverable exception", regs, SIGABRT);
+}
+
+/*
+ * We enter here if we discover during exception entry that we are
+ * running in supervisor mode with a userspace value in the stack pointer.
+ */
+void kernel_bad_stack(struct pt_regs *regs)
+{
+	printk(KERN_EMERG "Bad kernel stack pointer %lx at %lx\n",
+	       regs->gpr[1], regs->nip);
+	die("Bad kernel stack pointer", regs, SIGABRT);
+}
+
+void __init trap_init(void)
+{
+}