target/s390x: implement mvcos instruction

This adds support for the MOVE WITH OPTIONAL SPECIFICATIONS (MVCOS)
instruction. Allow to enable it for the qemu cpu model using

qemu-system-s390x ... -cpu qemu,mvcos=on ...

This allows to boot linux kernel that uses it for uacccess.

We are missing (as for most other part) low address protection checks,
PSW key / storage key checks and support for AR-mode.

We fake an ADDRESSING exception when called from problem state (which
seems to rely on PSW key checks to be in place) and if AR-mode is used.
user mode will always see a PRIVILEDGED exception.

This patch is based on an original patch by Miroslav Benes (thanks!).

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170614133819.18480-3-david@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
master
David Hildenbrand 2017-06-14 15:38:19 +02:00 committed by Richard Henderson
parent c8bd95377b
commit 3e7e5e0bc1
6 changed files with 201 additions and 15 deletions

View File

@ -304,6 +304,7 @@ void s390x_cpu_debug_excp_handler(CPUState *cs);
#undef PSW_MASK_WAIT
#undef PSW_MASK_PSTATE
#undef PSW_MASK_ASC
#undef PSW_SHIFT_ASC
#undef PSW_MASK_CC
#undef PSW_MASK_PM
#undef PSW_MASK_64
@ -320,6 +321,7 @@ void s390x_cpu_debug_excp_handler(CPUState *cs);
#define PSW_MASK_WAIT 0x0002000000000000ULL
#define PSW_MASK_PSTATE 0x0001000000000000ULL
#define PSW_MASK_ASC 0x0000C00000000000ULL
#define PSW_SHIFT_ASC 46
#define PSW_MASK_CC 0x0000300000000000ULL
#define PSW_MASK_PM 0x00000F0000000000ULL
#define PSW_MASK_64 0x0000000100000000ULL
@ -336,6 +338,12 @@ void s390x_cpu_debug_excp_handler(CPUState *cs);
#define PSW_ASC_SECONDARY 0x0000800000000000ULL
#define PSW_ASC_HOME 0x0000C00000000000ULL
/* the address space values shifted */
#define AS_PRIMARY 0
#define AS_ACCREG 1
#define AS_SECONDARY 2
#define AS_HOME 3
/* tb flags */
#define FLAG_MASK_PER (PSW_MASK_PER >> 32)
@ -354,6 +362,7 @@ void s390x_cpu_debug_excp_handler(CPUState *cs);
/* Control register 0 bits */
#define CR0_LOWPROT 0x0000000010000000ULL
#define CR0_SECONDARY 0x0000000004000000ULL
#define CR0_EDAT 0x0000000000800000ULL
/* MMU */
@ -361,7 +370,18 @@ void s390x_cpu_debug_excp_handler(CPUState *cs);
#define MMU_SECONDARY_IDX 1
#define MMU_HOME_IDX 2
static inline int cpu_mmu_index (CPUS390XState *env, bool ifetch)
static inline bool psw_key_valid(CPUS390XState *env, uint8_t psw_key)
{
uint16_t pkm = env->cregs[3] >> 16;
if (env->psw.mask & PSW_MASK_PSTATE) {
/* PSW key has range 0..15, it is valid if the bit is 1 in the PKM */
return pkm & (0x80 >> psw_key);
}
return true;
}
static inline int cpu_mmu_index(CPUS390XState *env, bool ifetch)
{
switch (env->psw.mask & PSW_MASK_ASC) {
case PSW_ASC_PRIMARY:

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@ -682,6 +682,7 @@ static void add_qemu_cpu_model_features(S390FeatBitmap fbm)
S390_FEAT_LONG_DISPLACEMENT_FAST,
S390_FEAT_ETF2_ENH,
S390_FEAT_STORE_CLOCK_FAST,
S390_FEAT_MOVE_WITH_OPTIONAL_SPEC,
S390_FEAT_GENERAL_INSTRUCTIONS_EXT,
S390_FEAT_EXECUTE_EXT,
S390_FEAT_STFLE_45,

View File

@ -105,6 +105,7 @@ DEF_HELPER_FLAGS_1(stfl, TCG_CALL_NO_RWG, void, env)
DEF_HELPER_2(stfle, i32, env, i64)
DEF_HELPER_FLAGS_2(lpq, TCG_CALL_NO_WG, i64, env, i64)
DEF_HELPER_FLAGS_4(stpq, TCG_CALL_NO_WG, void, env, i64, i64, i64)
DEF_HELPER_4(mvcos, i32, env, i64, i64, i64)
#ifndef CONFIG_USER_ONLY
DEF_HELPER_3(servc, i32, env, i64, i64)

View File

@ -590,6 +590,8 @@
C(0xb254, MVPG, RRE, Z, r1_o, r2_o, 0, 0, mvpg, 0)
/* MOVE STRING */
C(0xb255, MVST, RRE, Z, r1_o, r2_o, 0, 0, mvst, 0)
/* MOVE WITH OPTIONAL SPECIFICATION */
C(0xc800, MVCOS, SSF, MVCOS, la1, a2, 0, 0, mvcos, 0)
/* MOVE WITH OFFSET */
/* Really format SS_b, but we pack both lengths into one argument
for the helper call, so we might as well leave one 8-bit field. */

View File

@ -110,6 +110,20 @@ static inline void cpu_stsize_data_ra(CPUS390XState *env, uint64_t addr,
}
}
static inline uint64_t wrap_address(CPUS390XState *env, uint64_t a)
{
if (!(env->psw.mask & PSW_MASK_64)) {
if (!(env->psw.mask & PSW_MASK_32)) {
/* 24-Bit mode */
a &= 0x00ffffff;
} else {
/* 31-Bit mode */
a &= 0x7fffffff;
}
}
return a;
}
static void fast_memset(CPUS390XState *env, uint64_t dest, uint8_t byte,
uint32_t l, uintptr_t ra)
{
@ -133,6 +147,68 @@ static void fast_memset(CPUS390XState *env, uint64_t dest, uint8_t byte,
}
}
#ifndef CONFIG_USER_ONLY
static void fast_memmove_idx(CPUS390XState *env, uint64_t dest, uint64_t src,
uint32_t len, int dest_idx, int src_idx,
uintptr_t ra)
{
TCGMemOpIdx oi_dest = make_memop_idx(MO_UB, dest_idx);
TCGMemOpIdx oi_src = make_memop_idx(MO_UB, src_idx);
uint32_t len_adj;
void *src_p;
void *dest_p;
uint8_t x;
while (len > 0) {
src = wrap_address(env, src);
dest = wrap_address(env, dest);
src_p = tlb_vaddr_to_host(env, src, MMU_DATA_LOAD, src_idx);
dest_p = tlb_vaddr_to_host(env, dest, MMU_DATA_STORE, dest_idx);
if (src_p && dest_p) {
/* Access to both whole pages granted. */
len_adj = adj_len_to_page(adj_len_to_page(len, src), dest);
memmove(dest_p, src_p, len_adj);
} else {
/* We failed to get access to one or both whole pages. The next
read or write access will likely fill the QEMU TLB for the
next iteration. */
len_adj = 1;
x = helper_ret_ldub_mmu(env, src, oi_src, ra);
helper_ret_stb_mmu(env, dest, x, oi_dest, ra);
}
src += len_adj;
dest += len_adj;
len -= len_adj;
}
}
static int mmu_idx_from_as(uint8_t as)
{
switch (as) {
case AS_PRIMARY:
return MMU_PRIMARY_IDX;
case AS_SECONDARY:
return MMU_SECONDARY_IDX;
case AS_HOME:
return MMU_HOME_IDX;
default:
/* FIXME AS_ACCREG */
g_assert_not_reached();
}
}
static void fast_memmove_as(CPUS390XState *env, uint64_t dest, uint64_t src,
uint32_t len, uint8_t dest_as, uint8_t src_as,
uintptr_t ra)
{
int src_idx = mmu_idx_from_as(src_as);
int dest_idx = mmu_idx_from_as(dest_as);
fast_memmove_idx(env, dest, src, len, dest_idx, src_idx, ra);
}
#endif
static void fast_memmove(CPUS390XState *env, uint64_t dest, uint64_t src,
uint32_t l, uintptr_t ra)
{
@ -408,20 +484,6 @@ uint32_t HELPER(clm)(CPUS390XState *env, uint32_t r1, uint32_t mask,
return cc;
}
static inline uint64_t wrap_address(CPUS390XState *env, uint64_t a)
{
if (!(env->psw.mask & PSW_MASK_64)) {
if (!(env->psw.mask & PSW_MASK_32)) {
/* 24-Bit mode */
a &= 0x00ffffff;
} else {
/* 31-Bit mode */
a &= 0x7fffffff;
}
}
return a;
}
static inline uint64_t get_address(CPUS390XState *env, int reg)
{
return wrap_address(env, env->regs[reg]);
@ -1789,3 +1851,94 @@ void HELPER(ex)(CPUS390XState *env, uint32_t ilen, uint64_t r1, uint64_t addr)
that requires such execution. */
env->ex_value = insn | ilen;
}
uint32_t HELPER(mvcos)(CPUS390XState *env, uint64_t dest, uint64_t src,
uint64_t len)
{
const uint8_t psw_key = (env->psw.mask & PSW_MASK_KEY) >> PSW_SHIFT_KEY;
const uint8_t psw_as = (env->psw.mask & PSW_MASK_ASC) >> PSW_SHIFT_ASC;
const uint64_t r0 = env->regs[0];
const uintptr_t ra = GETPC();
CPUState *cs = CPU(s390_env_get_cpu(env));
uint8_t dest_key, dest_as, dest_k, dest_a;
uint8_t src_key, src_as, src_k, src_a;
uint64_t val;
int cc = 0;
HELPER_LOG("%s dest %" PRIx64 ", src %" PRIx64 ", len %" PRIx64 "\n",
__func__, dest, src, len);
if (!(env->psw.mask & PSW_MASK_DAT)) {
cpu_restore_state(cs, ra);
program_interrupt(env, PGM_SPECIAL_OP, 6);
}
/* OAC (operand access control) for the first operand -> dest */
val = (r0 & 0xffff0000ULL) >> 16;
dest_key = (val >> 12) & 0xf;
dest_as = (val >> 6) & 0x3;
dest_k = (val >> 1) & 0x1;
dest_a = val & 0x1;
/* OAC (operand access control) for the second operand -> src */
val = (r0 & 0x0000ffffULL);
src_key = (val >> 12) & 0xf;
src_as = (val >> 6) & 0x3;
src_k = (val >> 1) & 0x1;
src_a = val & 0x1;
if (!dest_k) {
dest_key = psw_key;
}
if (!src_k) {
src_key = psw_key;
}
if (!dest_a) {
dest_as = psw_as;
}
if (!src_a) {
src_as = psw_as;
}
if (dest_a && dest_as == AS_HOME && (env->psw.mask & PSW_MASK_PSTATE)) {
cpu_restore_state(cs, ra);
program_interrupt(env, PGM_SPECIAL_OP, 6);
}
if (!(env->cregs[0] & CR0_SECONDARY) &&
(dest_as == AS_SECONDARY || src_as == AS_SECONDARY)) {
cpu_restore_state(cs, ra);
program_interrupt(env, PGM_SPECIAL_OP, 6);
}
if (!psw_key_valid(env, dest_key) || !psw_key_valid(env, src_key)) {
cpu_restore_state(cs, ra);
program_interrupt(env, PGM_PRIVILEGED, 6);
}
len = wrap_length(env, len);
if (len > 4096) {
cc = 3;
len = 4096;
}
/* FIXME: AR-mode and proper problem state mode (using PSW keys) missing */
if (src_as == AS_ACCREG || dest_as == AS_ACCREG ||
(env->psw.mask & PSW_MASK_PSTATE)) {
qemu_log_mask(LOG_UNIMP, "%s: AR-mode and PSTATE support missing\n",
__func__);
cpu_restore_state(cs, ra);
program_interrupt(env, PGM_ADDRESSING, 6);
}
/* FIXME: a) LAP
* b) Access using correct keys
* c) AR-mode
*/
#ifdef CONFIG_USER_ONLY
/* psw keys are never valid in user mode, we will never reach this */
g_assert_not_reached();
#else
fast_memmove_as(env, dest, src, len, dest_as, src_as, ra);
#endif
return cc;
}

View File

@ -3041,6 +3041,14 @@ static ExitStatus op_mvclu(DisasContext *s, DisasOps *o)
return NO_EXIT;
}
static ExitStatus op_mvcos(DisasContext *s, DisasOps *o)
{
int r3 = get_field(s->fields, r3);
gen_helper_mvcos(cc_op, cpu_env, o->addr1, o->in2, regs[r3]);
set_cc_static(s);
return NO_EXIT;
}
#ifndef CONFIG_USER_ONLY
static ExitStatus op_mvcp(DisasContext *s, DisasOps *o)
{
@ -5413,6 +5421,7 @@ enum DisasInsnEnum {
#define FAC_SCF S390_FEAT_STORE_CLOCK_FAST
#define FAC_SFLE S390_FEAT_STFLE
#define FAC_ILA S390_FEAT_STFLE_45 /* interlocked-access-facility 1 */
#define FAC_MVCOS S390_FEAT_MOVE_WITH_OPTIONAL_SPEC
#define FAC_LPP S390_FEAT_SET_PROGRAM_PARAMETERS /* load-program-parameter */
#define FAC_DAT_ENH S390_FEAT_DAT_ENH
#define FAC_E2 S390_FEAT_EXTENDED_TRANSLATION_2