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		49f3bfe933
		
	
	
	
	
		
			
			vmemmap and the vmsplit code amongst others need to be able to take page faults much earlier than trap_init() time, so move this in to the early CPU initialization. VBR setup for secondary CPUs is already handled through start_secondary(), so we only need to do this for the boot CPU. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
		
			
				
	
	
		
			874 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			874 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * 'traps.c' handles hardware traps and faults after we have saved some
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|  * state in 'entry.S'.
 | |
|  *
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|  *  SuperH version: Copyright (C) 1999 Niibe Yutaka
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|  *                  Copyright (C) 2000 Philipp Rumpf
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|  *                  Copyright (C) 2000 David Howells
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|  *                  Copyright (C) 2002 - 2007 Paul Mundt
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|  *
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  */
 | |
| #include <linux/kernel.h>
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| #include <linux/ptrace.h>
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| #include <linux/hardirq.h>
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| #include <linux/init.h>
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| #include <linux/spinlock.h>
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| #include <linux/module.h>
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| #include <linux/kallsyms.h>
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| #include <linux/io.h>
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| #include <linux/bug.h>
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| #include <linux/debug_locks.h>
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| #include <linux/kdebug.h>
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| #include <linux/kexec.h>
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| #include <linux/limits.h>
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| #include <linux/sysfs.h>
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| #include <linux/uaccess.h>
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| #include <asm/system.h>
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| #include <asm/alignment.h>
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| #include <asm/fpu.h>
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| #include <asm/kprobes.h>
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| 
 | |
| #ifdef CONFIG_CPU_SH2
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| # define TRAP_RESERVED_INST	4
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| # define TRAP_ILLEGAL_SLOT_INST	6
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| # define TRAP_ADDRESS_ERROR	9
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| # ifdef CONFIG_CPU_SH2A
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| #  define TRAP_UBC		12
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| #  define TRAP_FPU_ERROR	13
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| #  define TRAP_DIVZERO_ERROR	17
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| #  define TRAP_DIVOVF_ERROR	18
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| # endif
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| #else
 | |
| #define TRAP_RESERVED_INST	12
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| #define TRAP_ILLEGAL_SLOT_INST	13
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| #endif
 | |
| 
 | |
| static void dump_mem(const char *str, unsigned long bottom, unsigned long top)
 | |
| {
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| 	unsigned long p;
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| 	int i;
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| 
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| 	printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
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| 
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| 	for (p = bottom & ~31; p < top; ) {
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| 		printk("%04lx: ", p & 0xffff);
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| 
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| 		for (i = 0; i < 8; i++, p += 4) {
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| 			unsigned int val;
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| 
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| 			if (p < bottom || p >= top)
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| 				printk("         ");
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| 			else {
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| 				if (__get_user(val, (unsigned int __user *)p)) {
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| 					printk("\n");
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| 					return;
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| 				}
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| 				printk("%08x ", val);
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| 			}
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| 		}
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| 		printk("\n");
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| 	}
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| }
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| 
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| static DEFINE_SPINLOCK(die_lock);
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| 
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| void die(const char * str, struct pt_regs * regs, long err)
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| {
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| 	static int die_counter;
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| 
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| 	oops_enter();
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| 
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| 	spin_lock_irq(&die_lock);
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| 	console_verbose();
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| 	bust_spinlocks(1);
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| 
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| 	printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
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| 	sysfs_printk_last_file();
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| 	print_modules();
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| 	show_regs(regs);
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| 
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| 	printk("Process: %s (pid: %d, stack limit = %p)\n", current->comm,
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| 			task_pid_nr(current), task_stack_page(current) + 1);
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| 
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| 	if (!user_mode(regs) || in_interrupt())
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| 		dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
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| 			 (unsigned long)task_stack_page(current));
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| 
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| 	notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV);
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| 
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| 	bust_spinlocks(0);
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| 	add_taint(TAINT_DIE);
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| 	spin_unlock_irq(&die_lock);
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| 	oops_exit();
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| 
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| 	if (kexec_should_crash(current))
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| 		crash_kexec(regs);
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| 
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| 	if (in_interrupt())
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| 		panic("Fatal exception in interrupt");
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| 
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| 	if (panic_on_oops)
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| 		panic("Fatal exception");
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| 
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| 	do_exit(SIGSEGV);
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| }
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| 
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| static inline void die_if_kernel(const char *str, struct pt_regs *regs,
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| 				 long err)
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| {
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| 	if (!user_mode(regs))
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| 		die(str, regs, err);
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| }
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| 
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| /*
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|  * try and fix up kernelspace address errors
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|  * - userspace errors just cause EFAULT to be returned, resulting in SEGV
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|  * - kernel/userspace interfaces cause a jump to an appropriate handler
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|  * - other kernel errors are bad
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|  */
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| static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
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| {
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| 	if (!user_mode(regs)) {
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| 		const struct exception_table_entry *fixup;
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| 		fixup = search_exception_tables(regs->pc);
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| 		if (fixup) {
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| 			regs->pc = fixup->fixup;
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| 			return;
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| 		}
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| 
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| 		die(str, regs, err);
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| 	}
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| }
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| 
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| static inline void sign_extend(unsigned int count, unsigned char *dst)
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| {
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| #ifdef __LITTLE_ENDIAN__
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| 	if ((count == 1) && dst[0] & 0x80) {
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| 		dst[1] = 0xff;
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| 		dst[2] = 0xff;
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| 		dst[3] = 0xff;
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| 	}
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| 	if ((count == 2) && dst[1] & 0x80) {
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| 		dst[2] = 0xff;
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| 		dst[3] = 0xff;
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| 	}
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| #else
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| 	if ((count == 1) && dst[3] & 0x80) {
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| 		dst[2] = 0xff;
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| 		dst[1] = 0xff;
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| 		dst[0] = 0xff;
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| 	}
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| 	if ((count == 2) && dst[2] & 0x80) {
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| 		dst[1] = 0xff;
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| 		dst[0] = 0xff;
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| 	}
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| #endif
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| }
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| 
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| static struct mem_access user_mem_access = {
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| 	copy_from_user,
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| 	copy_to_user,
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| };
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| 
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| /*
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|  * handle an instruction that does an unaligned memory access by emulating the
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|  * desired behaviour
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|  * - note that PC _may not_ point to the faulting instruction
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|  *   (if that instruction is in a branch delay slot)
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|  * - return 0 if emulation okay, -EFAULT on existential error
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|  */
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| static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
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| 				struct mem_access *ma)
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| {
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| 	int ret, index, count;
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| 	unsigned long *rm, *rn;
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| 	unsigned char *src, *dst;
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| 	unsigned char __user *srcu, *dstu;
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| 
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| 	index = (instruction>>8)&15;	/* 0x0F00 */
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| 	rn = ®s->regs[index];
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| 
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| 	index = (instruction>>4)&15;	/* 0x00F0 */
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| 	rm = ®s->regs[index];
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| 
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| 	count = 1<<(instruction&3);
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| 
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| 	switch (count) {
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| 	case 1: inc_unaligned_byte_access(); break;
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| 	case 2: inc_unaligned_word_access(); break;
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| 	case 4: inc_unaligned_dword_access(); break;
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| 	case 8: inc_unaligned_multi_access(); break;
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| 	}
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| 
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| 	ret = -EFAULT;
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| 	switch (instruction>>12) {
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| 	case 0: /* mov.[bwl] to/from memory via r0+rn */
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| 		if (instruction & 8) {
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| 			/* from memory */
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| 			srcu = (unsigned char __user *)*rm;
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| 			srcu += regs->regs[0];
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| 			dst = (unsigned char *)rn;
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| 			*(unsigned long *)dst = 0;
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| 
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| #if !defined(__LITTLE_ENDIAN__)
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| 			dst += 4-count;
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| #endif
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| 			if (ma->from(dst, srcu, count))
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| 				goto fetch_fault;
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| 
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| 			sign_extend(count, dst);
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| 		} else {
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| 			/* to memory */
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| 			src = (unsigned char *)rm;
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| #if !defined(__LITTLE_ENDIAN__)
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| 			src += 4-count;
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| #endif
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| 			dstu = (unsigned char __user *)*rn;
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| 			dstu += regs->regs[0];
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| 
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| 			if (ma->to(dstu, src, count))
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| 				goto fetch_fault;
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| 		}
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| 		ret = 0;
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| 		break;
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| 
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| 	case 1: /* mov.l Rm,@(disp,Rn) */
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| 		src = (unsigned char*) rm;
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| 		dstu = (unsigned char __user *)*rn;
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| 		dstu += (instruction&0x000F)<<2;
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| 
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| 		if (ma->to(dstu, src, 4))
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| 			goto fetch_fault;
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| 		ret = 0;
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| 		break;
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| 
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| 	case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
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| 		if (instruction & 4)
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| 			*rn -= count;
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| 		src = (unsigned char*) rm;
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| 		dstu = (unsigned char __user *)*rn;
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| #if !defined(__LITTLE_ENDIAN__)
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| 		src += 4-count;
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| #endif
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| 		if (ma->to(dstu, src, count))
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| 			goto fetch_fault;
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| 		ret = 0;
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| 		break;
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| 
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| 	case 5: /* mov.l @(disp,Rm),Rn */
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| 		srcu = (unsigned char __user *)*rm;
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| 		srcu += (instruction & 0x000F) << 2;
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| 		dst = (unsigned char *)rn;
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| 		*(unsigned long *)dst = 0;
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| 
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| 		if (ma->from(dst, srcu, 4))
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| 			goto fetch_fault;
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| 		ret = 0;
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| 		break;
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| 
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| 	case 6:	/* mov.[bwl] from memory, possibly with post-increment */
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| 		srcu = (unsigned char __user *)*rm;
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| 		if (instruction & 4)
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| 			*rm += count;
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| 		dst = (unsigned char*) rn;
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| 		*(unsigned long*)dst = 0;
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| 
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| #if !defined(__LITTLE_ENDIAN__)
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| 		dst += 4-count;
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| #endif
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| 		if (ma->from(dst, srcu, count))
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| 			goto fetch_fault;
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| 		sign_extend(count, dst);
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| 		ret = 0;
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| 		break;
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| 
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| 	case 8:
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| 		switch ((instruction&0xFF00)>>8) {
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| 		case 0x81: /* mov.w R0,@(disp,Rn) */
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| 			src = (unsigned char *) ®s->regs[0];
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| #if !defined(__LITTLE_ENDIAN__)
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| 			src += 2;
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| #endif
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| 			dstu = (unsigned char __user *)*rm; /* called Rn in the spec */
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| 			dstu += (instruction & 0x000F) << 1;
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| 
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| 			if (ma->to(dstu, src, 2))
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| 				goto fetch_fault;
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| 			ret = 0;
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| 			break;
 | |
| 
 | |
| 		case 0x85: /* mov.w @(disp,Rm),R0 */
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| 			srcu = (unsigned char __user *)*rm;
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| 			srcu += (instruction & 0x000F) << 1;
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| 			dst = (unsigned char *) ®s->regs[0];
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| 			*(unsigned long *)dst = 0;
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| 
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| #if !defined(__LITTLE_ENDIAN__)
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| 			dst += 2;
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| #endif
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| 			if (ma->from(dst, srcu, 2))
 | |
| 				goto fetch_fault;
 | |
| 			sign_extend(2, dst);
 | |
| 			ret = 0;
 | |
| 			break;
 | |
| 		}
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| 		break;
 | |
| 	}
 | |
| 	return ret;
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| 
 | |
|  fetch_fault:
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| 	/* Argh. Address not only misaligned but also non-existent.
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| 	 * Raise an EFAULT and see if it's trapped
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| 	 */
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| 	die_if_no_fixup("Fault in unaligned fixup", regs, 0);
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| 	return -EFAULT;
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| }
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| 
 | |
| /*
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|  * emulate the instruction in the delay slot
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|  * - fetches the instruction from PC+2
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|  */
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| static inline int handle_delayslot(struct pt_regs *regs,
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| 				   insn_size_t old_instruction,
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| 				   struct mem_access *ma)
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| {
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| 	insn_size_t instruction;
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| 	void __user *addr = (void __user *)(regs->pc +
 | |
| 		instruction_size(old_instruction));
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| 
 | |
| 	if (copy_from_user(&instruction, addr, sizeof(instruction))) {
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| 		/* the instruction-fetch faulted */
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| 		if (user_mode(regs))
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| 			return -EFAULT;
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| 
 | |
| 		/* kernel */
 | |
| 		die("delay-slot-insn faulting in handle_unaligned_delayslot",
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| 		    regs, 0);
 | |
| 	}
 | |
| 
 | |
| 	return handle_unaligned_ins(instruction, regs, ma);
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * handle an instruction that does an unaligned memory access
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|  * - have to be careful of branch delay-slot instructions that fault
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|  *  SH3:
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|  *   - if the branch would be taken PC points to the branch
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|  *   - if the branch would not be taken, PC points to delay-slot
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|  *  SH4:
 | |
|  *   - PC always points to delayed branch
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|  * - return 0 if handled, -EFAULT if failed (may not return if in kernel)
 | |
|  */
 | |
| 
 | |
| /* Macros to determine offset from current PC for branch instructions */
 | |
| /* Explicit type coercion is used to force sign extension where needed */
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| #define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
 | |
| #define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
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| 
 | |
| int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
 | |
| 			    struct mem_access *ma, int expected)
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| {
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| 	u_int rm;
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| 	int ret, index;
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| 
 | |
| 	/*
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| 	 * XXX: We can't handle mixed 16/32-bit instructions yet
 | |
| 	 */
 | |
| 	if (instruction_size(instruction) != 2)
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| 		return -EINVAL;
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| 
 | |
| 	index = (instruction>>8)&15;	/* 0x0F00 */
 | |
| 	rm = regs->regs[index];
 | |
| 
 | |
| 	/* shout about fixups */
 | |
| 	if (!expected)
 | |
| 		unaligned_fixups_notify(current, instruction, regs);
 | |
| 
 | |
| 	ret = -EFAULT;
 | |
| 	switch (instruction&0xF000) {
 | |
| 	case 0x0000:
 | |
| 		if (instruction==0x000B) {
 | |
| 			/* rts */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0)
 | |
| 				regs->pc = regs->pr;
 | |
| 		}
 | |
| 		else if ((instruction&0x00FF)==0x0023) {
 | |
| 			/* braf @Rm */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0)
 | |
| 				regs->pc += rm + 4;
 | |
| 		}
 | |
| 		else if ((instruction&0x00FF)==0x0003) {
 | |
| 			/* bsrf @Rm */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0) {
 | |
| 				regs->pr = regs->pc + 4;
 | |
| 				regs->pc += rm + 4;
 | |
| 			}
 | |
| 		}
 | |
| 		else {
 | |
| 			/* mov.[bwl] to/from memory via r0+rn */
 | |
| 			goto simple;
 | |
| 		}
 | |
| 		break;
 | |
| 
 | |
| 	case 0x1000: /* mov.l Rm,@(disp,Rn) */
 | |
| 		goto simple;
 | |
| 
 | |
| 	case 0x2000: /* mov.[bwl] to memory, possibly with pre-decrement */
 | |
| 		goto simple;
 | |
| 
 | |
| 	case 0x4000:
 | |
| 		if ((instruction&0x00FF)==0x002B) {
 | |
| 			/* jmp @Rm */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0)
 | |
| 				regs->pc = rm;
 | |
| 		}
 | |
| 		else if ((instruction&0x00FF)==0x000B) {
 | |
| 			/* jsr @Rm */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0) {
 | |
| 				regs->pr = regs->pc + 4;
 | |
| 				regs->pc = rm;
 | |
| 			}
 | |
| 		}
 | |
| 		else {
 | |
| 			/* mov.[bwl] to/from memory via r0+rn */
 | |
| 			goto simple;
 | |
| 		}
 | |
| 		break;
 | |
| 
 | |
| 	case 0x5000: /* mov.l @(disp,Rm),Rn */
 | |
| 		goto simple;
 | |
| 
 | |
| 	case 0x6000: /* mov.[bwl] from memory, possibly with post-increment */
 | |
| 		goto simple;
 | |
| 
 | |
| 	case 0x8000: /* bf lab, bf/s lab, bt lab, bt/s lab */
 | |
| 		switch (instruction&0x0F00) {
 | |
| 		case 0x0100: /* mov.w R0,@(disp,Rm) */
 | |
| 			goto simple;
 | |
| 		case 0x0500: /* mov.w @(disp,Rm),R0 */
 | |
| 			goto simple;
 | |
| 		case 0x0B00: /* bf   lab - no delayslot*/
 | |
| 			break;
 | |
| 		case 0x0F00: /* bf/s lab */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0) {
 | |
| #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
 | |
| 				if ((regs->sr & 0x00000001) != 0)
 | |
| 					regs->pc += 4; /* next after slot */
 | |
| 				else
 | |
| #endif
 | |
| 					regs->pc += SH_PC_8BIT_OFFSET(instruction);
 | |
| 			}
 | |
| 			break;
 | |
| 		case 0x0900: /* bt   lab - no delayslot */
 | |
| 			break;
 | |
| 		case 0x0D00: /* bt/s lab */
 | |
| 			ret = handle_delayslot(regs, instruction, ma);
 | |
| 			if (ret==0) {
 | |
| #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
 | |
| 				if ((regs->sr & 0x00000001) == 0)
 | |
| 					regs->pc += 4; /* next after slot */
 | |
| 				else
 | |
| #endif
 | |
| 					regs->pc += SH_PC_8BIT_OFFSET(instruction);
 | |
| 			}
 | |
| 			break;
 | |
| 		}
 | |
| 		break;
 | |
| 
 | |
| 	case 0xA000: /* bra label */
 | |
| 		ret = handle_delayslot(regs, instruction, ma);
 | |
| 		if (ret==0)
 | |
| 			regs->pc += SH_PC_12BIT_OFFSET(instruction);
 | |
| 		break;
 | |
| 
 | |
| 	case 0xB000: /* bsr label */
 | |
| 		ret = handle_delayslot(regs, instruction, ma);
 | |
| 		if (ret==0) {
 | |
| 			regs->pr = regs->pc + 4;
 | |
| 			regs->pc += SH_PC_12BIT_OFFSET(instruction);
 | |
| 		}
 | |
| 		break;
 | |
| 	}
 | |
| 	return ret;
 | |
| 
 | |
| 	/* handle non-delay-slot instruction */
 | |
|  simple:
 | |
| 	ret = handle_unaligned_ins(instruction, regs, ma);
 | |
| 	if (ret==0)
 | |
| 		regs->pc += instruction_size(instruction);
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Handle various address error exceptions:
 | |
|  *  - instruction address error:
 | |
|  *       misaligned PC
 | |
|  *       PC >= 0x80000000 in user mode
 | |
|  *  - data address error (read and write)
 | |
|  *       misaligned data access
 | |
|  *       access to >= 0x80000000 is user mode
 | |
|  * Unfortuntaly we can't distinguish between instruction address error
 | |
|  * and data address errors caused by read accesses.
 | |
|  */
 | |
| asmlinkage void do_address_error(struct pt_regs *regs,
 | |
| 				 unsigned long writeaccess,
 | |
| 				 unsigned long address)
 | |
| {
 | |
| 	unsigned long error_code = 0;
 | |
| 	mm_segment_t oldfs;
 | |
| 	siginfo_t info;
 | |
| 	insn_size_t instruction;
 | |
| 	int tmp;
 | |
| 
 | |
| 	/* Intentional ifdef */
 | |
| #ifdef CONFIG_CPU_HAS_SR_RB
 | |
| 	error_code = lookup_exception_vector();
 | |
| #endif
 | |
| 
 | |
| 	oldfs = get_fs();
 | |
| 
 | |
| 	if (user_mode(regs)) {
 | |
| 		int si_code = BUS_ADRERR;
 | |
| 		unsigned int user_action;
 | |
| 
 | |
| 		local_irq_enable();
 | |
| 		inc_unaligned_user_access();
 | |
| 
 | |
| 		set_fs(USER_DS);
 | |
| 		if (copy_from_user(&instruction, (insn_size_t *)(regs->pc & ~1),
 | |
| 				   sizeof(instruction))) {
 | |
| 			set_fs(oldfs);
 | |
| 			goto uspace_segv;
 | |
| 		}
 | |
| 		set_fs(oldfs);
 | |
| 
 | |
| 		/* shout about userspace fixups */
 | |
| 		unaligned_fixups_notify(current, instruction, regs);
 | |
| 
 | |
| 		user_action = unaligned_user_action();
 | |
| 		if (user_action & UM_FIXUP)
 | |
| 			goto fixup;
 | |
| 		if (user_action & UM_SIGNAL)
 | |
| 			goto uspace_segv;
 | |
| 		else {
 | |
| 			/* ignore */
 | |
| 			regs->pc += instruction_size(instruction);
 | |
| 			return;
 | |
| 		}
 | |
| 
 | |
| fixup:
 | |
| 		/* bad PC is not something we can fix */
 | |
| 		if (regs->pc & 1) {
 | |
| 			si_code = BUS_ADRALN;
 | |
| 			goto uspace_segv;
 | |
| 		}
 | |
| 
 | |
| 		set_fs(USER_DS);
 | |
| 		tmp = handle_unaligned_access(instruction, regs,
 | |
| 					      &user_mem_access, 0);
 | |
| 		set_fs(oldfs);
 | |
| 
 | |
| 		if (tmp == 0)
 | |
| 			return; /* sorted */
 | |
| uspace_segv:
 | |
| 		printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
 | |
| 		       "access (PC %lx PR %lx)\n", current->comm, regs->pc,
 | |
| 		       regs->pr);
 | |
| 
 | |
| 		info.si_signo = SIGBUS;
 | |
| 		info.si_errno = 0;
 | |
| 		info.si_code = si_code;
 | |
| 		info.si_addr = (void __user *)address;
 | |
| 		force_sig_info(SIGBUS, &info, current);
 | |
| 	} else {
 | |
| 		inc_unaligned_kernel_access();
 | |
| 
 | |
| 		if (regs->pc & 1)
 | |
| 			die("unaligned program counter", regs, error_code);
 | |
| 
 | |
| 		set_fs(KERNEL_DS);
 | |
| 		if (copy_from_user(&instruction, (void __user *)(regs->pc),
 | |
| 				   sizeof(instruction))) {
 | |
| 			/* Argh. Fault on the instruction itself.
 | |
| 			   This should never happen non-SMP
 | |
| 			*/
 | |
| 			set_fs(oldfs);
 | |
| 			die("insn faulting in do_address_error", regs, 0);
 | |
| 		}
 | |
| 
 | |
| 		unaligned_fixups_notify(current, instruction, regs);
 | |
| 
 | |
| 		handle_unaligned_access(instruction, regs,
 | |
| 					&user_mem_access, 0);
 | |
| 		set_fs(oldfs);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_SH_DSP
 | |
| /*
 | |
|  *	SH-DSP support gerg@snapgear.com.
 | |
|  */
 | |
| int is_dsp_inst(struct pt_regs *regs)
 | |
| {
 | |
| 	unsigned short inst = 0;
 | |
| 
 | |
| 	/*
 | |
| 	 * Safe guard if DSP mode is already enabled or we're lacking
 | |
| 	 * the DSP altogether.
 | |
| 	 */
 | |
| 	if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
 | |
| 		return 0;
 | |
| 
 | |
| 	get_user(inst, ((unsigned short *) regs->pc));
 | |
| 
 | |
| 	inst &= 0xf000;
 | |
| 
 | |
| 	/* Check for any type of DSP or support instruction */
 | |
| 	if ((inst == 0xf000) || (inst == 0x4000))
 | |
| 		return 1;
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| #else
 | |
| #define is_dsp_inst(regs)	(0)
 | |
| #endif /* CONFIG_SH_DSP */
 | |
| 
 | |
| #ifdef CONFIG_CPU_SH2A
 | |
| asmlinkage void do_divide_error(unsigned long r4, unsigned long r5,
 | |
| 				unsigned long r6, unsigned long r7,
 | |
| 				struct pt_regs __regs)
 | |
| {
 | |
| 	siginfo_t info;
 | |
| 
 | |
| 	switch (r4) {
 | |
| 	case TRAP_DIVZERO_ERROR:
 | |
| 		info.si_code = FPE_INTDIV;
 | |
| 		break;
 | |
| 	case TRAP_DIVOVF_ERROR:
 | |
| 		info.si_code = FPE_INTOVF;
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| 	force_sig_info(SIGFPE, &info, current);
 | |
| }
 | |
| #endif
 | |
| 
 | |
| asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
 | |
| 				unsigned long r6, unsigned long r7,
 | |
| 				struct pt_regs __regs)
 | |
| {
 | |
| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
 | |
| 	unsigned long error_code;
 | |
| 	struct task_struct *tsk = current;
 | |
| 
 | |
| #ifdef CONFIG_SH_FPU_EMU
 | |
| 	unsigned short inst = 0;
 | |
| 	int err;
 | |
| 
 | |
| 	get_user(inst, (unsigned short*)regs->pc);
 | |
| 
 | |
| 	err = do_fpu_inst(inst, regs);
 | |
| 	if (!err) {
 | |
| 		regs->pc += instruction_size(inst);
 | |
| 		return;
 | |
| 	}
 | |
| 	/* not a FPU inst. */
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_SH_DSP
 | |
| 	/* Check if it's a DSP instruction */
 | |
| 	if (is_dsp_inst(regs)) {
 | |
| 		/* Enable DSP mode, and restart instruction. */
 | |
| 		regs->sr |= SR_DSP;
 | |
| 		/* Save DSP mode */
 | |
| 		tsk->thread.dsp_status.status |= SR_DSP;
 | |
| 		return;
 | |
| 	}
 | |
| #endif
 | |
| 
 | |
| 	error_code = lookup_exception_vector();
 | |
| 
 | |
| 	local_irq_enable();
 | |
| 	force_sig(SIGILL, tsk);
 | |
| 	die_if_no_fixup("reserved instruction", regs, error_code);
 | |
| }
 | |
| 
 | |
| #ifdef CONFIG_SH_FPU_EMU
 | |
| static int emulate_branch(unsigned short inst, struct pt_regs *regs)
 | |
| {
 | |
| 	/*
 | |
| 	 * bfs: 8fxx: PC+=d*2+4;
 | |
| 	 * bts: 8dxx: PC+=d*2+4;
 | |
| 	 * bra: axxx: PC+=D*2+4;
 | |
| 	 * bsr: bxxx: PC+=D*2+4  after PR=PC+4;
 | |
| 	 * braf:0x23: PC+=Rn*2+4;
 | |
| 	 * bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
 | |
| 	 * jmp: 4x2b: PC=Rn;
 | |
| 	 * jsr: 4x0b: PC=Rn      after PR=PC+4;
 | |
| 	 * rts: 000b: PC=PR;
 | |
| 	 */
 | |
| 	if (((inst & 0xf000) == 0xb000)  ||	/* bsr */
 | |
| 	    ((inst & 0xf0ff) == 0x0003)  ||	/* bsrf */
 | |
| 	    ((inst & 0xf0ff) == 0x400b))	/* jsr */
 | |
| 		regs->pr = regs->pc + 4;
 | |
| 
 | |
| 	if ((inst & 0xfd00) == 0x8d00) {	/* bfs, bts */
 | |
| 		regs->pc += SH_PC_8BIT_OFFSET(inst);
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	if ((inst & 0xe000) == 0xa000) {	/* bra, bsr */
 | |
| 		regs->pc += SH_PC_12BIT_OFFSET(inst);
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	if ((inst & 0xf0df) == 0x0003) {	/* braf, bsrf */
 | |
| 		regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	if ((inst & 0xf0df) == 0x400b) {	/* jmp, jsr */
 | |
| 		regs->pc = regs->regs[(inst & 0x0f00) >> 8];
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	if ((inst & 0xffff) == 0x000b) {	/* rts */
 | |
| 		regs->pc = regs->pr;
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	return 1;
 | |
| }
 | |
| #endif
 | |
| 
 | |
| asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
 | |
| 				unsigned long r6, unsigned long r7,
 | |
| 				struct pt_regs __regs)
 | |
| {
 | |
| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
 | |
| 	unsigned long inst;
 | |
| 	struct task_struct *tsk = current;
 | |
| 
 | |
| 	if (kprobe_handle_illslot(regs->pc) == 0)
 | |
| 		return;
 | |
| 
 | |
| #ifdef CONFIG_SH_FPU_EMU
 | |
| 	get_user(inst, (unsigned short *)regs->pc + 1);
 | |
| 	if (!do_fpu_inst(inst, regs)) {
 | |
| 		get_user(inst, (unsigned short *)regs->pc);
 | |
| 		if (!emulate_branch(inst, regs))
 | |
| 			return;
 | |
| 		/* fault in branch.*/
 | |
| 	}
 | |
| 	/* not a FPU inst. */
 | |
| #endif
 | |
| 
 | |
| 	inst = lookup_exception_vector();
 | |
| 
 | |
| 	local_irq_enable();
 | |
| 	force_sig(SIGILL, tsk);
 | |
| 	die_if_no_fixup("illegal slot instruction", regs, inst);
 | |
| }
 | |
| 
 | |
| asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
 | |
| 				   unsigned long r6, unsigned long r7,
 | |
| 				   struct pt_regs __regs)
 | |
| {
 | |
| 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
 | |
| 	long ex;
 | |
| 
 | |
| 	ex = lookup_exception_vector();
 | |
| 	die_if_kernel("exception", regs, ex);
 | |
| }
 | |
| 
 | |
| void __cpuinit per_cpu_trap_init(void)
 | |
| {
 | |
| 	extern void *vbr_base;
 | |
| 
 | |
| 	/* NOTE: The VBR value should be at P1
 | |
| 	   (or P2, virtural "fixed" address space).
 | |
| 	   It's definitely should not in physical address.  */
 | |
| 
 | |
| 	asm volatile("ldc	%0, vbr"
 | |
| 		     : /* no output */
 | |
| 		     : "r" (&vbr_base)
 | |
| 		     : "memory");
 | |
| }
 | |
| 
 | |
| void *set_exception_table_vec(unsigned int vec, void *handler)
 | |
| {
 | |
| 	extern void *exception_handling_table[];
 | |
| 	void *old_handler;
 | |
| 
 | |
| 	old_handler = exception_handling_table[vec];
 | |
| 	exception_handling_table[vec] = handler;
 | |
| 	return old_handler;
 | |
| }
 | |
| 
 | |
| void __init trap_init(void)
 | |
| {
 | |
| 	set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
 | |
| 	set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
 | |
| 
 | |
| #if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
 | |
|     defined(CONFIG_SH_FPU_EMU)
 | |
| 	/*
 | |
| 	 * For SH-4 lacking an FPU, treat floating point instructions as
 | |
| 	 * reserved. They'll be handled in the math-emu case, or faulted on
 | |
| 	 * otherwise.
 | |
| 	 */
 | |
| 	set_exception_table_evt(0x800, do_reserved_inst);
 | |
| 	set_exception_table_evt(0x820, do_illegal_slot_inst);
 | |
| #elif defined(CONFIG_SH_FPU)
 | |
| 	set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
 | |
| 	set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
 | |
| #endif
 | |
| 
 | |
| #ifdef CONFIG_CPU_SH2
 | |
| 	set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_trap_handler);
 | |
| #endif
 | |
| #ifdef CONFIG_CPU_SH2A
 | |
| 	set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
 | |
| 	set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
 | |
| #ifdef CONFIG_SH_FPU
 | |
| 	set_exception_table_vec(TRAP_FPU_ERROR, fpu_error_trap_handler);
 | |
| #endif
 | |
| #endif
 | |
| 
 | |
| #ifdef TRAP_UBC
 | |
| 	set_exception_table_vec(TRAP_UBC, breakpoint_trap_handler);
 | |
| #endif
 | |
| }
 | |
| 
 | |
| void show_stack(struct task_struct *tsk, unsigned long *sp)
 | |
| {
 | |
| 	unsigned long stack;
 | |
| 
 | |
| 	if (!tsk)
 | |
| 		tsk = current;
 | |
| 	if (tsk == current)
 | |
| 		sp = (unsigned long *)current_stack_pointer;
 | |
| 	else
 | |
| 		sp = (unsigned long *)tsk->thread.sp;
 | |
| 
 | |
| 	stack = (unsigned long)sp;
 | |
| 	dump_mem("Stack: ", stack, THREAD_SIZE +
 | |
| 		 (unsigned long)task_stack_page(tsk));
 | |
| 	show_trace(tsk, sp, NULL);
 | |
| }
 | |
| 
 | |
| void dump_stack(void)
 | |
| {
 | |
| 	show_stack(NULL, NULL);
 | |
| }
 | |
| EXPORT_SYMBOL(dump_stack);
 |