Initial import

1 files changed, 652 insertions, 0 deletions

diff --git a/arch/ia64/kernel/traps.c b/arch/ia64/kernel/traps.c
new file mode 100644
index 000000000..6f7d4a4dc
--- /dev/null
+++ b/arch/ia64/kernel/traps.c
@@ -0,0 +1,652 @@
+/*
+ * Architecture-specific trap handling.
+ *
+ * Copyright (C) 1998-2003 Hewlett-Packard Co
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * 05/12/00 grao <goutham.rao@intel.com> : added isr in siginfo for SIGFPE
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/tty.h>
+#include <linux/vt_kern.h>		/* For unblank_screen() */
+#include <linux/module.h>       /* for EXPORT_SYMBOL */
+#include <linux/hardirq.h>
+#include <linux/kprobes.h>
+#include <linux/delay.h>		/* for ssleep() */
+#include <linux/kdebug.h>
+
+#include <asm/fpswa.h>
+#include <asm/intrinsics.h>
+#include <asm/processor.h>
+#include <asm/uaccess.h>
+#include <asm/setup.h>
+
+fpswa_interface_t *fpswa_interface;
+EXPORT_SYMBOL(fpswa_interface);
+
+void __init
+trap_init (void)
+{
+	if (ia64_boot_param->fpswa)
+		/* FPSWA fixup: make the interface pointer a kernel virtual address: */
+		fpswa_interface = __va(ia64_boot_param->fpswa);
+}
+
+int
+die (const char *str, struct pt_regs *regs, long err)
+{
+	static struct {
+		spinlock_t lock;
+		u32 lock_owner;
+		int lock_owner_depth;
+	} die = {
+		.lock =	__SPIN_LOCK_UNLOCKED(die.lock),
+		.lock_owner = -1,
+		.lock_owner_depth = 0
+	};
+	static int die_counter;
+	int cpu = get_cpu();
+
+	if (die.lock_owner != cpu) {
+		console_verbose();
+		spin_lock_irq(&die.lock);
+		die.lock_owner = cpu;
+		die.lock_owner_depth = 0;
+		bust_spinlocks(1);
+	}
+	put_cpu();
+
+	if (++die.lock_owner_depth < 3) {
+		printk("%s[%d]: %s %ld [%d]\n",
+		current->comm, task_pid_nr(current), str, err, ++die_counter);
+		if (notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV)
+	            != NOTIFY_STOP)
+			show_regs(regs);
+		else
+			regs = NULL;
+  	} else
+		printk(KERN_ERR "Recursive die() failure, output suppressed\n");
+
+	bust_spinlocks(0);
+	die.lock_owner = -1;
+	add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
+	spin_unlock_irq(&die.lock);
+
+	if (!regs)
+		return 1;
+
+	if (panic_on_oops)
+		panic("Fatal exception");
+
+  	do_exit(SIGSEGV);
+	return 0;
+}
+
+int
+die_if_kernel (char *str, struct pt_regs *regs, long err)
+{
+	if (!user_mode(regs))
+		return die(str, regs, err);
+	return 0;
+}
+
+void
+__kprobes ia64_bad_break (unsigned long break_num, struct pt_regs *regs)
+{
+	siginfo_t siginfo;
+	int sig, code;
+
+	/* SIGILL, SIGFPE, SIGSEGV, and SIGBUS want these field initialized: */
+	siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+	siginfo.si_imm = break_num;
+	siginfo.si_flags = 0;		/* clear __ISR_VALID */
+	siginfo.si_isr = 0;
+
+	switch (break_num) {
+	      case 0: /* unknown error (used by GCC for __builtin_abort()) */
+		if (notify_die(DIE_BREAK, "break 0", regs, break_num, TRAP_BRKPT, SIGTRAP)
+			       	== NOTIFY_STOP)
+			return;
+		if (die_if_kernel("bugcheck!", regs, break_num))
+			return;
+		sig = SIGILL; code = ILL_ILLOPC;
+		break;
+
+	      case 1: /* integer divide by zero */
+		sig = SIGFPE; code = FPE_INTDIV;
+		break;
+
+	      case 2: /* integer overflow */
+		sig = SIGFPE; code = FPE_INTOVF;
+		break;
+
+	      case 3: /* range check/bounds check */
+		sig = SIGFPE; code = FPE_FLTSUB;
+		break;
+
+	      case 4: /* null pointer dereference */
+		sig = SIGSEGV; code = SEGV_MAPERR;
+		break;
+
+	      case 5: /* misaligned data */
+		sig = SIGSEGV; code = BUS_ADRALN;
+		break;
+
+	      case 6: /* decimal overflow */
+		sig = SIGFPE; code = __FPE_DECOVF;
+		break;
+
+	      case 7: /* decimal divide by zero */
+		sig = SIGFPE; code = __FPE_DECDIV;
+		break;
+
+	      case 8: /* packed decimal error */
+		sig = SIGFPE; code = __FPE_DECERR;
+		break;
+
+	      case 9: /* invalid ASCII digit */
+		sig = SIGFPE; code = __FPE_INVASC;
+		break;
+
+	      case 10: /* invalid decimal digit */
+		sig = SIGFPE; code = __FPE_INVDEC;
+		break;
+
+	      case 11: /* paragraph stack overflow */
+		sig = SIGSEGV; code = __SEGV_PSTKOVF;
+		break;
+
+	      case 0x3f000 ... 0x3ffff:	/* bundle-update in progress */
+		sig = SIGILL; code = __ILL_BNDMOD;
+		break;
+
+	      default:
+		if ((break_num < 0x40000 || break_num > 0x100000)
+		    && die_if_kernel("Bad break", regs, break_num))
+			return;
+
+		if (break_num < 0x80000) {
+			sig = SIGILL; code = __ILL_BREAK;
+		} else {
+			if (notify_die(DIE_BREAK, "bad break", regs, break_num, TRAP_BRKPT, SIGTRAP)
+					== NOTIFY_STOP)
+				return;
+			sig = SIGTRAP; code = TRAP_BRKPT;
+		}
+	}
+	siginfo.si_signo = sig;
+	siginfo.si_errno = 0;
+	siginfo.si_code = code;
+	force_sig_info(sig, &siginfo, current);
+}
+
+/*
+ * disabled_fph_fault() is called when a user-level process attempts to access f32..f127
+ * and it doesn't own the fp-high register partition.  When this happens, we save the
+ * current fph partition in the task_struct of the fpu-owner (if necessary) and then load
+ * the fp-high partition of the current task (if necessary).  Note that the kernel has
+ * access to fph by the time we get here, as the IVT's "Disabled FP-Register" handler takes
+ * care of clearing psr.dfh.
+ */
+static inline void
+disabled_fph_fault (struct pt_regs *regs)
+{
+	struct ia64_psr *psr = ia64_psr(regs);
+
+	/* first, grant user-level access to fph partition: */
+	psr->dfh = 0;
+
+	/*
+	 * Make sure that no other task gets in on this processor
+	 * while we're claiming the FPU
+	 */
+	preempt_disable();
+#ifndef CONFIG_SMP
+	{
+		struct task_struct *fpu_owner
+			= (struct task_struct *)ia64_get_kr(IA64_KR_FPU_OWNER);
+
+		if (ia64_is_local_fpu_owner(current)) {
+			preempt_enable_no_resched();
+			return;
+		}
+
+		if (fpu_owner)
+			ia64_flush_fph(fpu_owner);
+	}
+#endif /* !CONFIG_SMP */
+	ia64_set_local_fpu_owner(current);
+	if ((current->thread.flags & IA64_THREAD_FPH_VALID) != 0) {
+		__ia64_load_fpu(current->thread.fph);
+		psr->mfh = 0;
+	} else {
+		__ia64_init_fpu();
+		/*
+		 * Set mfh because the state in thread.fph does not match the state in
+		 * the fph partition.
+		 */
+		psr->mfh = 1;
+	}
+	preempt_enable_no_resched();
+}
+
+static inline int
+fp_emulate (int fp_fault, void *bundle, long *ipsr, long *fpsr, long *isr, long *pr, long *ifs,
+	    struct pt_regs *regs)
+{
+	fp_state_t fp_state;
+	fpswa_ret_t ret;
+
+	if (!fpswa_interface)
+		return -1;
+
+	memset(&fp_state, 0, sizeof(fp_state_t));
+
+	/*
+	 * compute fp_state.  only FP registers f6 - f11 are used by the
+	 * kernel, so set those bits in the mask and set the low volatile
+	 * pointer to point to these registers.
+	 */
+	fp_state.bitmask_low64 = 0xfc0;  /* bit6..bit11 */
+
+	fp_state.fp_state_low_volatile = (fp_state_low_volatile_t *) &regs->f6;
+	/*
+	 * unsigned long (*EFI_FPSWA) (
+	 *      unsigned long    trap_type,
+	 *	void             *Bundle,
+	 *	unsigned long    *pipsr,
+	 *	unsigned long    *pfsr,
+	 *	unsigned long    *pisr,
+	 *	unsigned long    *ppreds,
+	 *	unsigned long    *pifs,
+	 *	void             *fp_state);
+	 */
+	ret = (*fpswa_interface->fpswa)((unsigned long) fp_fault, bundle,
+					(unsigned long *) ipsr, (unsigned long *) fpsr,
+					(unsigned long *) isr, (unsigned long *) pr,
+					(unsigned long *) ifs, &fp_state);
+
+	return ret.status;
+}
+
+struct fpu_swa_msg {
+	unsigned long count;
+	unsigned long time;
+};
+static DEFINE_PER_CPU(struct fpu_swa_msg, cpulast);
+DECLARE_PER_CPU(struct fpu_swa_msg, cpulast);
+static struct fpu_swa_msg last __cacheline_aligned;
+
+
+/*
+ * Handle floating-point assist faults and traps.
+ */
+static int
+handle_fpu_swa (int fp_fault, struct pt_regs *regs, unsigned long isr)
+{
+	long exception, bundle[2];
+	unsigned long fault_ip;
+	struct siginfo siginfo;
+
+	fault_ip = regs->cr_iip;
+	if (!fp_fault && (ia64_psr(regs)->ri == 0))
+		fault_ip -= 16;
+	if (copy_from_user(bundle, (void __user *) fault_ip, sizeof(bundle)))
+		return -1;
+
+	if (!(current->thread.flags & IA64_THREAD_FPEMU_NOPRINT))  {
+		unsigned long count, current_jiffies = jiffies;
+		struct fpu_swa_msg *cp = this_cpu_ptr(&cpulast);
+
+		if (unlikely(current_jiffies > cp->time))
+			cp->count = 0;
+		if (unlikely(cp->count < 5)) {
+			cp->count++;
+			cp->time = current_jiffies + 5 * HZ;
+
+			/* minimize races by grabbing a copy of count BEFORE checking last.time. */
+			count = last.count;
+			barrier();
+
+			/*
+			 * Lower 4 bits are used as a count. Upper bits are a sequence
+			 * number that is updated when count is reset. The cmpxchg will
+			 * fail is seqno has changed. This minimizes mutiple cpus
+			 * resetting the count.
+			 */
+			if (current_jiffies > last.time)
+				(void) cmpxchg_acq(&last.count, count, 16 + (count & ~15));
+
+			/* used fetchadd to atomically update the count */
+			if ((last.count & 15) < 5 && (ia64_fetchadd(1, &last.count, acq) & 15) < 5) {
+				last.time = current_jiffies + 5 * HZ;
+				printk(KERN_WARNING
+		       			"%s(%d): floating-point assist fault at ip %016lx, isr %016lx\n",
+		       			current->comm, task_pid_nr(current), regs->cr_iip + ia64_psr(regs)->ri, isr);
+			}
+		}
+	}
+
+	exception = fp_emulate(fp_fault, bundle, &regs->cr_ipsr, &regs->ar_fpsr, &isr, &regs->pr,
+			       &regs->cr_ifs, regs);
+	if (fp_fault) {
+		if (exception == 0) {
+			/* emulation was successful */
+			ia64_increment_ip(regs);
+		} else if (exception == -1) {
+			printk(KERN_ERR "handle_fpu_swa: fp_emulate() returned -1\n");
+			return -1;
+		} else {
+			/* is next instruction a trap? */
+			if (exception & 2) {
+				ia64_increment_ip(regs);
+			}
+			siginfo.si_signo = SIGFPE;
+			siginfo.si_errno = 0;
+			siginfo.si_code = __SI_FAULT;	/* default code */
+			siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+			if (isr & 0x11) {
+				siginfo.si_code = FPE_FLTINV;
+			} else if (isr & 0x22) {
+				/* denormal operand gets the same si_code as underflow 
+				* see arch/i386/kernel/traps.c:math_error()  */
+				siginfo.si_code = FPE_FLTUND;
+			} else if (isr & 0x44) {
+				siginfo.si_code = FPE_FLTDIV;
+			}
+			siginfo.si_isr = isr;
+			siginfo.si_flags = __ISR_VALID;
+			siginfo.si_imm = 0;
+			force_sig_info(SIGFPE, &siginfo, current);
+		}
+	} else {
+		if (exception == -1) {
+			printk(KERN_ERR "handle_fpu_swa: fp_emulate() returned -1\n");
+			return -1;
+		} else if (exception != 0) {
+			/* raise exception */
+			siginfo.si_signo = SIGFPE;
+			siginfo.si_errno = 0;
+			siginfo.si_code = __SI_FAULT;	/* default code */
+			siginfo.si_addr = (void __user *) (regs->cr_iip + ia64_psr(regs)->ri);
+			if (isr & 0x880) {
+				siginfo.si_code = FPE_FLTOVF;
+			} else if (isr & 0x1100) {
+				siginfo.si_code = FPE_FLTUND;
+			} else if (isr & 0x2200) {
+				siginfo.si_code = FPE_FLTRES;
+			}
+			siginfo.si_isr = isr;
+			siginfo.si_flags = __ISR_VALID;
+			siginfo.si_imm = 0;
+			force_sig_info(SIGFPE, &siginfo, current);
+		}
+	}
+	return 0;
+}
+
+struct illegal_op_return {
+	unsigned long fkt, arg1, arg2, arg3;
+};
+
+struct illegal_op_return
+ia64_illegal_op_fault (unsigned long ec, long arg1, long arg2, long arg3,
+		       long arg4, long arg5, long arg6, long arg7,
+		       struct pt_regs regs)
+{
+	struct illegal_op_return rv;
+	struct siginfo si;
+	char buf[128];
+
+#ifdef CONFIG_IA64_BRL_EMU
+	{
+		extern struct illegal_op_return ia64_emulate_brl (struct pt_regs *, unsigned long);
+
+		rv = ia64_emulate_brl(&regs, ec);
+		if (rv.fkt != (unsigned long) -1)
+			return rv;
+	}
+#endif
+
+	sprintf(buf, "IA-64 Illegal operation fault");
+	rv.fkt = 0;
+	if (die_if_kernel(buf, &regs, 0))
+		return rv;
+
+	memset(&si, 0, sizeof(si));
+	si.si_signo = SIGILL;
+	si.si_code = ILL_ILLOPC;
+	si.si_addr = (void __user *) (regs.cr_iip + ia64_psr(&regs)->ri);
+	force_sig_info(SIGILL, &si, current);
+	return rv;
+}
+
+void __kprobes
+ia64_fault (unsigned long vector, unsigned long isr, unsigned long ifa,
+	    unsigned long iim, unsigned long itir, long arg5, long arg6,
+	    long arg7, struct pt_regs regs)
+{
+	unsigned long code, error = isr, iip;
+	struct siginfo siginfo;
+	char buf[128];
+	int result, sig;
+	static const char *reason[] = {
+		"IA-64 Illegal Operation fault",
+		"IA-64 Privileged Operation fault",
+		"IA-64 Privileged Register fault",
+		"IA-64 Reserved Register/Field fault",
+		"Disabled Instruction Set Transition fault",
+		"Unknown fault 5", "Unknown fault 6", "Unknown fault 7", "Illegal Hazard fault",
+		"Unknown fault 9", "Unknown fault 10", "Unknown fault 11", "Unknown fault 12",
+		"Unknown fault 13", "Unknown fault 14", "Unknown fault 15"
+	};
+
+	if ((isr & IA64_ISR_NA) && ((isr & IA64_ISR_CODE_MASK) == IA64_ISR_CODE_LFETCH)) {
+		/*
+		 * This fault was due to lfetch.fault, set "ed" bit in the psr to cancel
+		 * the lfetch.
+		 */
+		ia64_psr(&regs)->ed = 1;
+		return;
+	}
+
+	iip = regs.cr_iip + ia64_psr(&regs)->ri;
+
+	switch (vector) {
+	      case 24: /* General Exception */
+		code = (isr >> 4) & 0xf;
+		sprintf(buf, "General Exception: %s%s", reason[code],
+			(code == 3) ? ((isr & (1UL << 37))
+				       ? " (RSE access)" : " (data access)") : "");
+		if (code == 8) {
+# ifdef CONFIG_IA64_PRINT_HAZARDS
+			printk("%s[%d]: possible hazard @ ip=%016lx (pr = %016lx)\n",
+			       current->comm, task_pid_nr(current),
+			       regs.cr_iip + ia64_psr(&regs)->ri, regs.pr);
+# endif
+			return;
+		}
+		break;
+
+	      case 25: /* Disabled FP-Register */
+		if (isr & 2) {
+			disabled_fph_fault(&regs);
+			return;
+		}
+		sprintf(buf, "Disabled FPL fault---not supposed to happen!");
+		break;
+
+	      case 26: /* NaT Consumption */
+		if (user_mode(&regs)) {
+			void __user *addr;
+
+			if (((isr >> 4) & 0xf) == 2) {
+				/* NaT page consumption */
+				sig = SIGSEGV;
+				code = SEGV_ACCERR;
+				addr = (void __user *) ifa;
+			} else {
+				/* register NaT consumption */
+				sig = SIGILL;
+				code = ILL_ILLOPN;
+				addr = (void __user *) (regs.cr_iip
+							+ ia64_psr(&regs)->ri);
+			}
+			siginfo.si_signo = sig;
+			siginfo.si_code = code;
+			siginfo.si_errno = 0;
+			siginfo.si_addr = addr;
+			siginfo.si_imm = vector;
+			siginfo.si_flags = __ISR_VALID;
+			siginfo.si_isr = isr;
+			force_sig_info(sig, &siginfo, current);
+			return;
+		} else if (ia64_done_with_exception(&regs))
+			return;
+		sprintf(buf, "NaT consumption");
+		break;
+
+	      case 31: /* Unsupported Data Reference */
+		if (user_mode(&regs)) {
+			siginfo.si_signo = SIGILL;
+			siginfo.si_code = ILL_ILLOPN;
+			siginfo.si_errno = 0;
+			siginfo.si_addr = (void __user *) iip;
+			siginfo.si_imm = vector;
+			siginfo.si_flags = __ISR_VALID;
+			siginfo.si_isr = isr;
+			force_sig_info(SIGILL, &siginfo, current);
+			return;
+		}
+		sprintf(buf, "Unsupported data reference");
+		break;
+
+	      case 29: /* Debug */
+	      case 35: /* Taken Branch Trap */
+	      case 36: /* Single Step Trap */
+		if (fsys_mode(current, &regs)) {
+			extern char __kernel_syscall_via_break[];
+			/*
+			 * Got a trap in fsys-mode: Taken Branch Trap
+			 * and Single Step trap need special handling;
+			 * Debug trap is ignored (we disable it here
+			 * and re-enable it in the lower-privilege trap).
+			 */
+			if (unlikely(vector == 29)) {
+				set_thread_flag(TIF_DB_DISABLED);
+				ia64_psr(&regs)->db = 0;
+				ia64_psr(&regs)->lp = 1;
+				return;
+			}
+			/* re-do the system call via break 0x100000: */
+			regs.cr_iip = (unsigned long) __kernel_syscall_via_break;
+			ia64_psr(&regs)->ri = 0;
+			ia64_psr(&regs)->cpl = 3;
+			return;
+		}
+		switch (vector) {
+		      case 29:
+			siginfo.si_code = TRAP_HWBKPT;
+#ifdef CONFIG_ITANIUM
+			/*
+			 * Erratum 10 (IFA may contain incorrect address) now has
+			 * "NoFix" status.  There are no plans for fixing this.
+			 */
+			if (ia64_psr(&regs)->is == 0)
+			  ifa = regs.cr_iip;
+#endif
+			break;
+		      case 35: siginfo.si_code = TRAP_BRANCH; ifa = 0; break;
+		      case 36: siginfo.si_code = TRAP_TRACE; ifa = 0; break;
+		}
+		if (notify_die(DIE_FAULT, "ia64_fault", &regs, vector, siginfo.si_code, SIGTRAP)
+			       	== NOTIFY_STOP)
+			return;
+		siginfo.si_signo = SIGTRAP;
+		siginfo.si_errno = 0;
+		siginfo.si_addr  = (void __user *) ifa;
+		siginfo.si_imm   = 0;
+		siginfo.si_flags = __ISR_VALID;
+		siginfo.si_isr   = isr;
+		force_sig_info(SIGTRAP, &siginfo, current);
+		return;
+
+	      case 32: /* fp fault */
+	      case 33: /* fp trap */
+		result = handle_fpu_swa((vector == 32) ? 1 : 0, &regs, isr);
+		if ((result < 0) || (current->thread.flags & IA64_THREAD_FPEMU_SIGFPE)) {
+			siginfo.si_signo = SIGFPE;
+			siginfo.si_errno = 0;
+			siginfo.si_code = FPE_FLTINV;
+			siginfo.si_addr = (void __user *) iip;
+			siginfo.si_flags = __ISR_VALID;
+			siginfo.si_isr = isr;
+			siginfo.si_imm = 0;
+			force_sig_info(SIGFPE, &siginfo, current);
+		}
+		return;
+
+	      case 34:
+		if (isr & 0x2) {
+			/* Lower-Privilege Transfer Trap */
+
+			/* If we disabled debug traps during an fsyscall,
+			 * re-enable them here.
+			 */
+			if (test_thread_flag(TIF_DB_DISABLED)) {
+				clear_thread_flag(TIF_DB_DISABLED);
+				ia64_psr(&regs)->db = 1;
+			}
+
+			/*
+			 * Just clear PSR.lp and then return immediately:
+			 * all the interesting work (e.g., signal delivery)
+			 * is done in the kernel exit path.
+			 */
+			ia64_psr(&regs)->lp = 0;
+			return;
+		} else {
+			/* Unimplemented Instr. Address Trap */
+			if (user_mode(&regs)) {
+				siginfo.si_signo = SIGILL;
+				siginfo.si_code = ILL_BADIADDR;
+				siginfo.si_errno = 0;
+				siginfo.si_flags = 0;
+				siginfo.si_isr = 0;
+				siginfo.si_imm = 0;
+				siginfo.si_addr = (void __user *) iip;
+				force_sig_info(SIGILL, &siginfo, current);
+				return;
+			}
+			sprintf(buf, "Unimplemented Instruction Address fault");
+		}
+		break;
+
+	      case 45:
+		printk(KERN_ERR "Unexpected IA-32 exception (Trap 45)\n");
+		printk(KERN_ERR "  iip - 0x%lx, ifa - 0x%lx, isr - 0x%lx\n",
+		       iip, ifa, isr);
+		force_sig(SIGSEGV, current);
+		return;
+
+	      case 46:
+		printk(KERN_ERR "Unexpected IA-32 intercept trap (Trap 46)\n");
+		printk(KERN_ERR "  iip - 0x%lx, ifa - 0x%lx, isr - 0x%lx, iim - 0x%lx\n",
+		       iip, ifa, isr, iim);
+		force_sig(SIGSEGV, current);
+		return;
+
+	      case 47:
+		sprintf(buf, "IA-32 Interruption Fault (int 0x%lx)", isr >> 16);
+		break;
+
+	      default:
+		sprintf(buf, "Fault %lu", vector);
+		break;
+	}
+	if (!die_if_kernel(buf, &regs, error))
+		force_sig(SIGILL, current);
+}