MN10300: Handle misaligned postinc-with-imm addressing mode correctly
Correctly handle misalignment in MOV instructions with postinc-with-immediate
addressing mode operands. In these, the immediate value is the increment to
be applied the address register, not the displacement to the address.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/mn10300/mm/misalignment.c b/arch/mn10300/mm/misalignment.c
index d5b45bb..61e65ec 100644
--- a/arch/mn10300/mm/misalignment.c
+++ b/arch/mn10300/mm/misalignment.c
@@ -44,7 +44,8 @@
static int misalignment_addr(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
- void **_address, unsigned long **_postinc);
+ void **_address, unsigned long **_postinc,
+ unsigned long *_inc);
static int misalignment_reg(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
@@ -150,7 +151,7 @@
};
struct mn10300_opcode {
- const char *name;
+ const char name[8];
u_int32_t opcode;
u_int32_t opmask;
unsigned exclusion;
@@ -310,7 +311,7 @@
{ "mov_lne", 0xf7e00009, 0xffff000f, 0x22, FMT_D10, AM33, {MEMINC2 (RN4,SIMM4_2), RM6}},
{ "mov_lra", 0xf7e0000a, 0xffff000f, 0x22, FMT_D10, AM33, {MEMINC2 (RN4,SIMM4_2), RM6}},
-{ 0, 0, 0, 0, 0, 0, {0}},
+{ "", 0, 0, 0, 0, 0, {0}},
};
/*
@@ -321,11 +322,11 @@
const struct exception_table_entry *fixup;
const struct mn10300_opcode *pop;
unsigned long *registers = (unsigned long *) regs;
- unsigned long data, *store, *postinc, disp;
+ unsigned long data, *store, *postinc, disp, inc;
mm_segment_t seg;
siginfo_t info;
uint32_t opcode, noc, xo, xm;
- uint8_t *pc, byte;
+ uint8_t *pc, byte, datasz;
void *address;
unsigned tmp, npop, dispsz, loop;
@@ -347,7 +348,7 @@
opcode = byte;
noc = 8;
- for (pop = mn10300_opcodes; pop->name; pop++) {
+ for (pop = mn10300_opcodes; pop->name[0]; pop++) {
npop = ilog2(pop->opcode | pop->opmask);
if (npop <= 0 || npop > 31)
continue;
@@ -484,32 +485,31 @@
goto failed;
}
+ /* determine the data transfer size of the move */
+ if (pop->name[3] == 0 || /* "mov" */
+ pop->name[4] == 'l') /* mov_lcc */
+ inc = datasz = 4;
+ else if (pop->name[3] == 'h') /* movhu */
+ inc = datasz = 2;
+ else
+ goto unsupported_instruction;
+
if (pop->params[0] & 0x80000000) {
/* move memory to register */
if (!misalignment_addr(registers, pop->params[0], opcode, disp,
- &address, &postinc))
+ &address, &postinc, &inc))
goto bad_addr_mode;
if (!misalignment_reg(registers, pop->params[1], opcode, disp,
&store))
goto bad_reg_mode;
- if (strcmp(pop->name, "mov") == 0 ||
- memcmp(pop->name, "mov_l", 5) == 0) {
- kdebug("mov (%p),DARn", address);
- if (copy_from_user(&data, (void *) address, 4) != 0)
- goto transfer_failed;
- if (pop->params[0] & 0x1000000)
- *postinc += 4;
- } else if (strcmp(pop->name, "movhu") == 0) {
- kdebug("movhu (%p),DARn", address);
- data = 0;
- if (copy_from_user(&data, (void *) address, 2) != 0)
- goto transfer_failed;
- if (pop->params[0] & 0x1000000)
- *postinc += 2;
- } else {
- goto unsupported_instruction;
+ kdebug("mov%u (%p),DARn", datasz, address);
+ if (copy_from_user(&data, (void *) address, datasz) != 0)
+ goto transfer_failed;
+ if (pop->params[0] & 0x1000000) {
+ kdebug("inc=%lx", inc);
+ *postinc += inc;
}
*store = data;
@@ -521,26 +521,16 @@
goto bad_reg_mode;
if (!misalignment_addr(registers, pop->params[1], opcode, disp,
- &address, &postinc))
+ &address, &postinc, &inc))
goto bad_addr_mode;
data = *store;
- if (strcmp(pop->name, "mov") == 0) {
- kdebug("mov %lx,(%p)", data, address);
- if (copy_to_user((void *) address, &data, 4) != 0)
- goto transfer_failed;
- if (pop->params[1] & 0x1000000)
- *postinc += 4;
- } else if (strcmp(pop->name, "movhu") == 0) {
- kdebug("movhu %hx,(%p)", (uint16_t) data, address);
- if (copy_to_user((void *) address, &data, 2) != 0)
- goto transfer_failed;
- if (pop->params[1] & 0x1000000)
- *postinc += 2;
- } else {
- goto unsupported_instruction;
- }
+ kdebug("mov%u %lx,(%p)", datasz, data, address);
+ if (copy_to_user((void *) address, &data, datasz) != 0)
+ goto transfer_failed;
+ if (pop->params[1] & 0x1000000)
+ *postinc += inc;
}
tmp = format_tbl[pop->format].opsz + format_tbl[pop->format].dispsz;
@@ -560,10 +550,17 @@
*/
static int misalignment_addr(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
- void **_address, unsigned long **_postinc)
+ void **_address, unsigned long **_postinc,
+ unsigned long *_inc)
{
unsigned long *postinc = NULL, address = 0, tmp;
+ if (!(params & 0x1000000)) {
+ kdebug("noinc");
+ *_inc = 0;
+ _inc = NULL;
+ }
+
params &= 0x00ffffff;
do {
@@ -624,32 +621,40 @@
address += registers[REG_SP >> 2];
break;
+ /* displacements are either to be added to the address
+ * before use, or, in the case of post-inc addressing,
+ * to be added into the base register after use */
case SD8:
case SIMM8:
- address += (int32_t) (int8_t) (disp & 0xff);
- break;
+ disp = (long) (int8_t) (disp & 0xff);
+ goto displace_or_inc;
case SD16:
- address += (int32_t) (int16_t) (disp & 0xffff);
- break;
+ disp = (long) (int16_t) (disp & 0xffff);
+ goto displace_or_inc;
case SD24:
tmp = disp << 8;
asm("asr 8,%0" : "=r"(tmp) : "0"(tmp));
- address += tmp;
- break;
+ disp = (long) tmp;
+ goto displace_or_inc;
case SIMM4_2:
tmp = opcode >> 4 & 0x0f;
tmp <<= 28;
asm("asr 28,%0" : "=r"(tmp) : "0"(tmp));
- address += tmp;
- break;
+ disp = (long) tmp;
+ goto displace_or_inc;
case IMM24:
- address += disp & 0x00ffffff;
- break;
+ disp &= 0x00ffffff;
+ goto displace_or_inc;
case IMM32:
case IMM32_MEM:
case IMM32_HIGH8:
case IMM32_HIGH8_MEM:
- address += disp;
+ displace_or_inc:
+ kdebug("%s %lx", _inc ? "incr" : "disp", disp);
+ if (!_inc)
+ address += disp;
+ else
+ *_inc = disp;
break;
default:
BUG();