qemu-e2k/accel/tcg/atomic_template.h
Peter Maydell 34d49937e4 accel/tcg: Handle atomic accesses to notdirty memory correctly
To do a write to memory that is marked as notdirty, we need
to invalidate any TBs we have cached for that memory, and
update the cpu physical memory dirty flags for VGA and migration.
The slowpath code in notdirty_mem_write() does all this correctly,
but the new atomic handling code in atomic_mmu_lookup() doesn't
do anything at all, it just clears the dirty bit in the TLB.

The effect of this bug is that if the first write to a notdirty
page for which we have cached TBs is by a guest atomic access,
we fail to invalidate the TBs and subsequently will execute
incorrect code. This can be seen by trying to run 'javac' on AArch64.

Use the new notdirty_call_before() and notdirty_call_after()
functions to correctly handle the update to notdirty memory
in the atomic codepath.

Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 1511201308-23580-3-git-send-email-peter.maydell@linaro.org
2017-11-21 12:09:25 +00:00

246 lines
7.0 KiB
C

/*
* Atomic helper templates
* Included from tcg-runtime.c and cputlb.c.
*
* Copyright (c) 2016 Red Hat, Inc
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#if DATA_SIZE == 16
# define SUFFIX o
# define DATA_TYPE Int128
# define BSWAP bswap128
#elif DATA_SIZE == 8
# define SUFFIX q
# define DATA_TYPE uint64_t
# define BSWAP bswap64
#elif DATA_SIZE == 4
# define SUFFIX l
# define DATA_TYPE uint32_t
# define BSWAP bswap32
#elif DATA_SIZE == 2
# define SUFFIX w
# define DATA_TYPE uint16_t
# define BSWAP bswap16
#elif DATA_SIZE == 1
# define SUFFIX b
# define DATA_TYPE uint8_t
# define BSWAP
#else
# error unsupported data size
#endif
#if DATA_SIZE >= 4
# define ABI_TYPE DATA_TYPE
#else
# define ABI_TYPE uint32_t
#endif
/* Define host-endian atomic operations. Note that END is used within
the ATOMIC_NAME macro, and redefined below. */
#if DATA_SIZE == 1
# define END
#elif defined(HOST_WORDS_BIGENDIAN)
# define END _be
#else
# define END _le
#endif
ABI_TYPE ATOMIC_NAME(cmpxchg)(CPUArchState *env, target_ulong addr,
ABI_TYPE cmpv, ABI_TYPE newv EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
DATA_TYPE ret = atomic_cmpxchg__nocheck(haddr, cmpv, newv);
ATOMIC_MMU_CLEANUP;
return ret;
}
#if DATA_SIZE >= 16
ABI_TYPE ATOMIC_NAME(ld)(CPUArchState *env, target_ulong addr EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE val, *haddr = ATOMIC_MMU_LOOKUP;
__atomic_load(haddr, &val, __ATOMIC_RELAXED);
ATOMIC_MMU_CLEANUP;
return val;
}
void ATOMIC_NAME(st)(CPUArchState *env, target_ulong addr,
ABI_TYPE val EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
__atomic_store(haddr, &val, __ATOMIC_RELAXED);
ATOMIC_MMU_CLEANUP;
}
#else
ABI_TYPE ATOMIC_NAME(xchg)(CPUArchState *env, target_ulong addr,
ABI_TYPE val EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
DATA_TYPE ret = atomic_xchg__nocheck(haddr, val);
ATOMIC_MMU_CLEANUP;
return ret;
}
#define GEN_ATOMIC_HELPER(X) \
ABI_TYPE ATOMIC_NAME(X)(CPUArchState *env, target_ulong addr, \
ABI_TYPE val EXTRA_ARGS) \
{ \
ATOMIC_MMU_DECLS; \
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP; \
DATA_TYPE ret = atomic_##X(haddr, val); \
ATOMIC_MMU_CLEANUP; \
return ret; \
}
GEN_ATOMIC_HELPER(fetch_add)
GEN_ATOMIC_HELPER(fetch_and)
GEN_ATOMIC_HELPER(fetch_or)
GEN_ATOMIC_HELPER(fetch_xor)
GEN_ATOMIC_HELPER(add_fetch)
GEN_ATOMIC_HELPER(and_fetch)
GEN_ATOMIC_HELPER(or_fetch)
GEN_ATOMIC_HELPER(xor_fetch)
#undef GEN_ATOMIC_HELPER
#endif /* DATA SIZE >= 16 */
#undef END
#if DATA_SIZE > 1
/* Define reverse-host-endian atomic operations. Note that END is used
within the ATOMIC_NAME macro. */
#ifdef HOST_WORDS_BIGENDIAN
# define END _le
#else
# define END _be
#endif
ABI_TYPE ATOMIC_NAME(cmpxchg)(CPUArchState *env, target_ulong addr,
ABI_TYPE cmpv, ABI_TYPE newv EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
DATA_TYPE ret = atomic_cmpxchg__nocheck(haddr, BSWAP(cmpv), BSWAP(newv));
ATOMIC_MMU_CLEANUP;
return BSWAP(ret);
}
#if DATA_SIZE >= 16
ABI_TYPE ATOMIC_NAME(ld)(CPUArchState *env, target_ulong addr EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE val, *haddr = ATOMIC_MMU_LOOKUP;
__atomic_load(haddr, &val, __ATOMIC_RELAXED);
ATOMIC_MMU_CLEANUP;
return BSWAP(val);
}
void ATOMIC_NAME(st)(CPUArchState *env, target_ulong addr,
ABI_TYPE val EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
val = BSWAP(val);
__atomic_store(haddr, &val, __ATOMIC_RELAXED);
ATOMIC_MMU_CLEANUP;
}
#else
ABI_TYPE ATOMIC_NAME(xchg)(CPUArchState *env, target_ulong addr,
ABI_TYPE val EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
ABI_TYPE ret = atomic_xchg__nocheck(haddr, BSWAP(val));
ATOMIC_MMU_CLEANUP;
return BSWAP(ret);
}
#define GEN_ATOMIC_HELPER(X) \
ABI_TYPE ATOMIC_NAME(X)(CPUArchState *env, target_ulong addr, \
ABI_TYPE val EXTRA_ARGS) \
{ \
ATOMIC_MMU_DECLS; \
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP; \
DATA_TYPE ret = atomic_##X(haddr, BSWAP(val)); \
ATOMIC_MMU_CLEANUP; \
return BSWAP(ret); \
}
GEN_ATOMIC_HELPER(fetch_and)
GEN_ATOMIC_HELPER(fetch_or)
GEN_ATOMIC_HELPER(fetch_xor)
GEN_ATOMIC_HELPER(and_fetch)
GEN_ATOMIC_HELPER(or_fetch)
GEN_ATOMIC_HELPER(xor_fetch)
#undef GEN_ATOMIC_HELPER
/* Note that for addition, we need to use a separate cmpxchg loop instead
of bswaps for the reverse-host-endian helpers. */
ABI_TYPE ATOMIC_NAME(fetch_add)(CPUArchState *env, target_ulong addr,
ABI_TYPE val EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
DATA_TYPE ldo, ldn, ret, sto;
ldo = atomic_read__nocheck(haddr);
while (1) {
ret = BSWAP(ldo);
sto = BSWAP(ret + val);
ldn = atomic_cmpxchg__nocheck(haddr, ldo, sto);
if (ldn == ldo) {
ATOMIC_MMU_CLEANUP;
return ret;
}
ldo = ldn;
}
}
ABI_TYPE ATOMIC_NAME(add_fetch)(CPUArchState *env, target_ulong addr,
ABI_TYPE val EXTRA_ARGS)
{
ATOMIC_MMU_DECLS;
DATA_TYPE *haddr = ATOMIC_MMU_LOOKUP;
DATA_TYPE ldo, ldn, ret, sto;
ldo = atomic_read__nocheck(haddr);
while (1) {
ret = BSWAP(ldo) + val;
sto = BSWAP(ret);
ldn = atomic_cmpxchg__nocheck(haddr, ldo, sto);
if (ldn == ldo) {
ATOMIC_MMU_CLEANUP;
return ret;
}
ldo = ldn;
}
}
#endif /* DATA_SIZE >= 16 */
#undef END
#endif /* DATA_SIZE > 1 */
#undef BSWAP
#undef ABI_TYPE
#undef DATA_TYPE
#undef SUFFIX
#undef DATA_SIZE