in kernel/unaligned.c [435:694]
void handle_unaligned(struct pt_regs *regs)
{
static DEFINE_RATELIMIT_STATE(ratelimit, 5 * HZ, 5);
unsigned long newbase = R1(regs->iir)?regs->gr[R1(regs->iir)]:0;
int modify = 0;
int ret = ERR_NOTHANDLED;
register int flop=0; /* true if this is a flop */
__inc_irq_stat(irq_unaligned_count);
/* log a message with pacing */
if (user_mode(regs)) {
if (current->thread.flags & PARISC_UAC_SIGBUS) {
goto force_sigbus;
}
if (!(current->thread.flags & PARISC_UAC_NOPRINT) &&
__ratelimit(&ratelimit)) {
char buf[256];
sprintf(buf, "%s(%d): unaligned access to 0x" RFMT " at ip=0x" RFMT "\n",
current->comm, task_pid_nr(current), regs->ior, regs->iaoq[0]);
printk(KERN_WARNING "%s", buf);
#ifdef DEBUG_UNALIGNED
show_regs(regs);
#endif
}
if (!unaligned_enabled)
goto force_sigbus;
}
/* handle modification - OK, it's ugly, see the instruction manual */
switch (MAJOR_OP(regs->iir))
{
case 0x03:
case 0x09:
case 0x0b:
if (regs->iir&0x20)
{
modify = 1;
if (regs->iir&0x1000) /* short loads */
if (regs->iir&0x200)
newbase += IM5_3(regs->iir);
else
newbase += IM5_2(regs->iir);
else if (regs->iir&0x2000) /* scaled indexed */
{
int shift=0;
switch (regs->iir & OPCODE1_MASK)
{
case OPCODE_LDH_I:
shift= 1; break;
case OPCODE_LDW_I:
shift= 2; break;
case OPCODE_LDD_I:
case OPCODE_LDDA_I:
shift= 3; break;
}
newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0)<<shift;
} else /* simple indexed */
newbase += (R2(regs->iir)?regs->gr[R2(regs->iir)]:0);
}
break;
case 0x13:
case 0x1b:
modify = 1;
newbase += IM14(regs->iir);
break;
case 0x14:
case 0x1c:
if (regs->iir&8)
{
modify = 1;
newbase += IM14(regs->iir&~0xe);
}
break;
case 0x16:
case 0x1e:
modify = 1;
newbase += IM14(regs->iir&6);
break;
case 0x17:
case 0x1f:
if (regs->iir&4)
{
modify = 1;
newbase += IM14(regs->iir&~4);
}
break;
}
/* TODO: make this cleaner... */
switch (regs->iir & OPCODE1_MASK)
{
case OPCODE_LDH_I:
case OPCODE_LDH_S:
ret = emulate_ldh(regs, R3(regs->iir));
break;
case OPCODE_LDW_I:
case OPCODE_LDWA_I:
case OPCODE_LDW_S:
case OPCODE_LDWA_S:
ret = emulate_ldw(regs, R3(regs->iir),0);
break;
case OPCODE_STH:
ret = emulate_sth(regs, R2(regs->iir));
break;
case OPCODE_STW:
case OPCODE_STWA:
ret = emulate_stw(regs, R2(regs->iir),0);
break;
#ifdef CONFIG_PA20
case OPCODE_LDD_I:
case OPCODE_LDDA_I:
case OPCODE_LDD_S:
case OPCODE_LDDA_S:
ret = emulate_ldd(regs, R3(regs->iir),0);
break;
case OPCODE_STD:
case OPCODE_STDA:
ret = emulate_std(regs, R2(regs->iir),0);
break;
#endif
case OPCODE_FLDWX:
case OPCODE_FLDWS:
case OPCODE_FLDWXR:
case OPCODE_FLDWSR:
flop=1;
ret = emulate_ldw(regs,FR3(regs->iir),1);
break;
case OPCODE_FLDDX:
case OPCODE_FLDDS:
flop=1;
ret = emulate_ldd(regs,R3(regs->iir),1);
break;
case OPCODE_FSTWX:
case OPCODE_FSTWS:
case OPCODE_FSTWXR:
case OPCODE_FSTWSR:
flop=1;
ret = emulate_stw(regs,FR3(regs->iir),1);
break;
case OPCODE_FSTDX:
case OPCODE_FSTDS:
flop=1;
ret = emulate_std(regs,R3(regs->iir),1);
break;
case OPCODE_LDCD_I:
case OPCODE_LDCW_I:
case OPCODE_LDCD_S:
case OPCODE_LDCW_S:
ret = ERR_NOTHANDLED; /* "undefined", but lets kill them. */
break;
}
#ifdef CONFIG_PA20
switch (regs->iir & OPCODE2_MASK)
{
case OPCODE_FLDD_L:
flop=1;
ret = emulate_ldd(regs,R2(regs->iir),1);
break;
case OPCODE_FSTD_L:
flop=1;
ret = emulate_std(regs, R2(regs->iir),1);
break;
case OPCODE_LDD_L:
ret = emulate_ldd(regs, R2(regs->iir),0);
break;
case OPCODE_STD_L:
ret = emulate_std(regs, R2(regs->iir),0);
break;
}
#endif
switch (regs->iir & OPCODE3_MASK)
{
case OPCODE_FLDW_L:
flop=1;
ret = emulate_ldw(regs, R2(regs->iir),0);
break;
case OPCODE_LDW_M:
ret = emulate_ldw(regs, R2(regs->iir),1);
break;
case OPCODE_FSTW_L:
flop=1;
ret = emulate_stw(regs, R2(regs->iir),1);
break;
case OPCODE_STW_M:
ret = emulate_stw(regs, R2(regs->iir),0);
break;
}
switch (regs->iir & OPCODE4_MASK)
{
case OPCODE_LDH_L:
ret = emulate_ldh(regs, R2(regs->iir));
break;
case OPCODE_LDW_L:
case OPCODE_LDWM:
ret = emulate_ldw(regs, R2(regs->iir),0);
break;
case OPCODE_STH_L:
ret = emulate_sth(regs, R2(regs->iir));
break;
case OPCODE_STW_L:
case OPCODE_STWM:
ret = emulate_stw(regs, R2(regs->iir),0);
break;
}
if (ret == 0 && modify && R1(regs->iir))
regs->gr[R1(regs->iir)] = newbase;
if (ret == ERR_NOTHANDLED)
printk(KERN_CRIT "Not-handled unaligned insn 0x%08lx\n", regs->iir);
DPRINTF("ret = %d\n", ret);
if (ret)
{
/*
* The unaligned handler failed.
* If we were called by __get_user() or __put_user() jump
* to it's exception fixup handler instead of crashing.
*/
if (!user_mode(regs) && fixup_exception(regs))
return;
printk(KERN_CRIT "Unaligned handler failed, ret = %d\n", ret);
die_if_kernel("Unaligned data reference", regs, 28);
if (ret == ERR_PAGEFAULT)
{
force_sig_fault(SIGSEGV, SEGV_MAPERR,
(void __user *)regs->ior);
}
else
{
force_sigbus:
/* couldn't handle it ... */
force_sig_fault(SIGBUS, BUS_ADRALN,
(void __user *)regs->ior);
}
return;
}
/* else we handled it, let life go on. */
regs->gr[0]|=PSW_N;
}