- if (!user_mode(regs))
- {
- const struct exception_table_entry *fixup;
- fixup = search_exception_tables(regs->pc);
- if (fixup) {
- regs->pc = fixup->fixup;
- return 0;
- }
- die(str, regs, err);
- }
- return -EFAULT;
-}
-
-/*
- * handle an instruction that does an unaligned memory access by emulating the
- * desired behaviour
- * - note that PC _may not_ point to the faulting instruction
- * (if that instruction is in a branch delay slot)
- * - return 0 if emulation okay, -EFAULT on existential error
- */
-static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
-{
- int ret, index, count;
- unsigned long *rm, *rn;
- unsigned char *src, *dst;
-
- index = (instruction>>8)&15; /* 0x0F00 */
- rn = ®s->regs[index];
-
- index = (instruction>>4)&15; /* 0x00F0 */
- rm = ®s->regs[index];
-
- count = 1<<(instruction&3);
-
- ret = -EFAULT;
- switch (instruction>>12) {
- case 0: /* mov.[bwl] to/from memory via r0+rn */
- if (instruction & 8) {
- /* from memory */
- src = (unsigned char*) *rm;
- src += regs->regs[0];
- dst = (unsigned char*) rn;
- *(unsigned long*)dst = 0;
-
-#ifdef __LITTLE_ENDIAN__
- if (copy_from_user(dst, src, count))
- goto fetch_fault;
-
- if ((count == 2) && dst[1] & 0x80) {
- dst[2] = 0xff;
- dst[3] = 0xff;
- }
-#else
- dst += 4-count;
-
- if (__copy_user(dst, src, count))
- goto fetch_fault;
-
- if ((count == 2) && dst[2] & 0x80) {
- dst[0] = 0xff;
- dst[1] = 0xff;
- }
-#endif
- } else {
- /* to memory */
- src = (unsigned char*) rm;
-#if !defined(__LITTLE_ENDIAN__)
- src += 4-count;
-#endif
- dst = (unsigned char*) *rn;
- dst += regs->regs[0];
-
- if (copy_to_user(dst, src, count))
- goto fetch_fault;
- }
- ret = 0;
- break;
-
- case 1: /* mov.l Rm,@(disp,Rn) */
- src = (unsigned char*) rm;
- dst = (unsigned char*) *rn;
- dst += (instruction&0x000F)<<2;
-
- if (copy_to_user(dst,src,4))
- goto fetch_fault;
- ret = 0;
- break;
-
- case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
- if (instruction & 4)
- *rn -= count;
- src = (unsigned char*) rm;
- dst = (unsigned char*) *rn;
-#if !defined(__LITTLE_ENDIAN__)
- src += 4-count;
-#endif
- if (copy_to_user(dst, src, count))
- goto fetch_fault;
- ret = 0;
- break;
-
- case 5: /* mov.l @(disp,Rm),Rn */
- src = (unsigned char*) *rm;
- src += (instruction&0x000F)<<2;
- dst = (unsigned char*) rn;
- *(unsigned long*)dst = 0;
-
- if (copy_from_user(dst,src,4))
- goto fetch_fault;
- ret = 0;
- break;
-
- case 6: /* mov.[bwl] from memory, possibly with post-increment */
- src = (unsigned char*) *rm;
- if (instruction & 4)
- *rm += count;
- dst = (unsigned char*) rn;
- *(unsigned long*)dst = 0;
-
-#ifdef __LITTLE_ENDIAN__
- if (copy_from_user(dst, src, count))
- goto fetch_fault;
-
- if ((count == 2) && dst[1] & 0x80) {
- dst[2] = 0xff;
- dst[3] = 0xff;
- }
-#else
- dst += 4-count;
-
- if (copy_from_user(dst, src, count))
- goto fetch_fault;
-
- if ((count == 2) && dst[2] & 0x80) {
- dst[0] = 0xff;
- dst[1] = 0xff;
- }
-#endif
- ret = 0;
- break;
-
- case 8:
- switch ((instruction&0xFF00)>>8) {
- case 0x81: /* mov.w R0,@(disp,Rn) */
- src = (unsigned char*) ®s->regs[0];
-#if !defined(__LITTLE_ENDIAN__)
- src += 2;
-#endif
- dst = (unsigned char*) *rm; /* called Rn in the spec */
- dst += (instruction&0x000F)<<1;
-
- if (copy_to_user(dst, src, 2))
- goto fetch_fault;
- ret = 0;
- break;
-
- case 0x85: /* mov.w @(disp,Rm),R0 */
- src = (unsigned char*) *rm;
- src += (instruction&0x000F)<<1;
- dst = (unsigned char*) ®s->regs[0];
- *(unsigned long*)dst = 0;
-
-#if !defined(__LITTLE_ENDIAN__)
- dst += 2;
-#endif
-
- if (copy_from_user(dst, src, 2))
- goto fetch_fault;
-
-#ifdef __LITTLE_ENDIAN__
- if (dst[1] & 0x80) {
- dst[2] = 0xff;
- dst[3] = 0xff;
- }
-#else
- if (dst[2] & 0x80) {
- dst[0] = 0xff;
- dst[1] = 0xff;
- }
-#endif
- ret = 0;
- break;
- }
- break;