| /* |
| * Routines common to user and system emulation of load/store. |
| * |
| * Copyright (c) 2022 Linaro, Ltd. |
| * |
| * SPDX-License-Identifier: GPL-2.0-or-later |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| * See the COPYING file in the top-level directory. |
| */ |
| |
| #include "host/load-extract-al16-al8.h" |
| #include "host/store-insert-al16.h" |
| |
| #ifdef CONFIG_ATOMIC64 |
| # define HAVE_al8 true |
| #else |
| # define HAVE_al8 false |
| #endif |
| #define HAVE_al8_fast (ATOMIC_REG_SIZE >= 8) |
| |
| /** |
| * required_atomicity: |
| * |
| * Return the lg2 bytes of atomicity required by @memop for @p. |
| * If the operation must be split into two operations to be |
| * examined separately for atomicity, return -lg2. |
| */ |
| static int required_atomicity(CPUState *cpu, uintptr_t p, MemOp memop) |
| { |
| MemOp atom = memop & MO_ATOM_MASK; |
| MemOp size = memop & MO_SIZE; |
| MemOp half = size ? size - 1 : 0; |
| unsigned tmp; |
| int atmax; |
| |
| switch (atom) { |
| case MO_ATOM_NONE: |
| atmax = MO_8; |
| break; |
| |
| case MO_ATOM_IFALIGN_PAIR: |
| size = half; |
| /* fall through */ |
| |
| case MO_ATOM_IFALIGN: |
| tmp = (1 << size) - 1; |
| atmax = p & tmp ? MO_8 : size; |
| break; |
| |
| case MO_ATOM_WITHIN16: |
| tmp = p & 15; |
| atmax = (tmp + (1 << size) <= 16 ? size : MO_8); |
| break; |
| |
| case MO_ATOM_WITHIN16_PAIR: |
| tmp = p & 15; |
| if (tmp + (1 << size) <= 16) { |
| atmax = size; |
| } else if (tmp + (1 << half) == 16) { |
| /* |
| * The pair exactly straddles the boundary. |
| * Both halves are naturally aligned and atomic. |
| */ |
| atmax = half; |
| } else { |
| /* |
| * One of the pair crosses the boundary, and is non-atomic. |
| * The other of the pair does not cross, and is atomic. |
| */ |
| atmax = -half; |
| } |
| break; |
| |
| case MO_ATOM_SUBALIGN: |
| /* |
| * Examine the alignment of p to determine if there are subobjects |
| * that must be aligned. Note that we only really need ctz4() -- |
| * any more sigificant bits are discarded by the immediately |
| * following comparison. |
| */ |
| tmp = ctz32(p); |
| atmax = MIN(size, tmp); |
| break; |
| |
| default: |
| g_assert_not_reached(); |
| } |
| |
| /* |
| * Here we have the architectural atomicity of the operation. |
| * However, when executing in a serial context, we need no extra |
| * host atomicity in order to avoid racing. This reduction |
| * avoids looping with cpu_loop_exit_atomic. |
| */ |
| if (cpu_in_serial_context(cpu)) { |
| return MO_8; |
| } |
| return atmax; |
| } |
| |
| /** |
| * load_atomic2: |
| * @pv: host address |
| * |
| * Atomically load 2 aligned bytes from @pv. |
| */ |
| static inline uint16_t load_atomic2(void *pv) |
| { |
| uint16_t *p = __builtin_assume_aligned(pv, 2); |
| return qatomic_read(p); |
| } |
| |
| /** |
| * load_atomic4: |
| * @pv: host address |
| * |
| * Atomically load 4 aligned bytes from @pv. |
| */ |
| static inline uint32_t load_atomic4(void *pv) |
| { |
| uint32_t *p = __builtin_assume_aligned(pv, 4); |
| return qatomic_read(p); |
| } |
| |
| /** |
| * load_atomic8: |
| * @pv: host address |
| * |
| * Atomically load 8 aligned bytes from @pv. |
| */ |
| static inline uint64_t load_atomic8(void *pv) |
| { |
| uint64_t *p = __builtin_assume_aligned(pv, 8); |
| |
| qemu_build_assert(HAVE_al8); |
| return qatomic_read__nocheck(p); |
| } |
| |
| /** |
| * load_atomic8_or_exit: |
| * @cpu: generic cpu state |
| * @ra: host unwind address |
| * @pv: host address |
| * |
| * Atomically load 8 aligned bytes from @pv. |
| * If this is not possible, longjmp out to restart serially. |
| */ |
| static uint64_t load_atomic8_or_exit(CPUState *cpu, uintptr_t ra, void *pv) |
| { |
| if (HAVE_al8) { |
| return load_atomic8(pv); |
| } |
| |
| #ifdef CONFIG_USER_ONLY |
| /* |
| * If the page is not writable, then assume the value is immutable |
| * and requires no locking. This ignores the case of MAP_SHARED with |
| * another process, because the fallback start_exclusive solution |
| * provides no protection across processes. |
| */ |
| WITH_MMAP_LOCK_GUARD() { |
| if (!page_check_range(h2g(pv), 8, PAGE_WRITE_ORG)) { |
| uint64_t *p = __builtin_assume_aligned(pv, 8); |
| return *p; |
| } |
| } |
| #endif |
| |
| /* Ultimate fallback: re-execute in serial context. */ |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
| |
| /** |
| * load_atomic16_or_exit: |
| * @cpu: generic cpu state |
| * @ra: host unwind address |
| * @pv: host address |
| * |
| * Atomically load 16 aligned bytes from @pv. |
| * If this is not possible, longjmp out to restart serially. |
| */ |
| static Int128 load_atomic16_or_exit(CPUState *cpu, uintptr_t ra, void *pv) |
| { |
| Int128 *p = __builtin_assume_aligned(pv, 16); |
| |
| if (HAVE_ATOMIC128_RO) { |
| return atomic16_read_ro(p); |
| } |
| |
| /* |
| * We can only use cmpxchg to emulate a load if the page is writable. |
| * If the page is not writable, then assume the value is immutable |
| * and requires no locking. This ignores the case of MAP_SHARED with |
| * another process, because the fallback start_exclusive solution |
| * provides no protection across processes. |
| * |
| * In system mode all guest pages are writable. For user mode, |
| * we must take mmap_lock so that the query remains valid until |
| * the write is complete -- tests/tcg/multiarch/munmap-pthread.c |
| * is an example that can race. |
| */ |
| WITH_MMAP_LOCK_GUARD() { |
| #ifdef CONFIG_USER_ONLY |
| if (!page_check_range(h2g(p), 16, PAGE_WRITE_ORG)) { |
| return *p; |
| } |
| #endif |
| if (HAVE_ATOMIC128_RW) { |
| return atomic16_read_rw(p); |
| } |
| } |
| |
| /* Ultimate fallback: re-execute in serial context. */ |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
| |
| /** |
| * load_atom_extract_al4x2: |
| * @pv: host address |
| * |
| * Load 4 bytes from @p, from two sequential atomic 4-byte loads. |
| */ |
| static uint32_t load_atom_extract_al4x2(void *pv) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int sh = (pi & 3) * 8; |
| uint32_t a, b; |
| |
| pv = (void *)(pi & ~3); |
| a = load_atomic4(pv); |
| b = load_atomic4(pv + 4); |
| |
| if (HOST_BIG_ENDIAN) { |
| return (a << sh) | (b >> (-sh & 31)); |
| } else { |
| return (a >> sh) | (b << (-sh & 31)); |
| } |
| } |
| |
| /** |
| * load_atom_extract_al8x2: |
| * @pv: host address |
| * |
| * Load 8 bytes from @p, from two sequential atomic 8-byte loads. |
| */ |
| static uint64_t load_atom_extract_al8x2(void *pv) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int sh = (pi & 7) * 8; |
| uint64_t a, b; |
| |
| pv = (void *)(pi & ~7); |
| a = load_atomic8(pv); |
| b = load_atomic8(pv + 8); |
| |
| if (HOST_BIG_ENDIAN) { |
| return (a << sh) | (b >> (-sh & 63)); |
| } else { |
| return (a >> sh) | (b << (-sh & 63)); |
| } |
| } |
| |
| /** |
| * load_atom_extract_al8_or_exit: |
| * @cpu: generic cpu state |
| * @ra: host unwind address |
| * @pv: host address |
| * @s: object size in bytes, @s <= 4. |
| * |
| * Atomically load @s bytes from @p, when p % s != 0, and [p, p+s-1] does |
| * not cross an 8-byte boundary. This means that we can perform an atomic |
| * 8-byte load and extract. |
| * The value is returned in the low bits of a uint32_t. |
| */ |
| static uint32_t load_atom_extract_al8_or_exit(CPUState *cpu, uintptr_t ra, |
| void *pv, int s) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int o = pi & 7; |
| int shr = (HOST_BIG_ENDIAN ? 8 - s - o : o) * 8; |
| |
| pv = (void *)(pi & ~7); |
| return load_atomic8_or_exit(cpu, ra, pv) >> shr; |
| } |
| |
| /** |
| * load_atom_extract_al16_or_exit: |
| * @cpu: generic cpu state |
| * @ra: host unwind address |
| * @p: host address |
| * @s: object size in bytes, @s <= 8. |
| * |
| * Atomically load @s bytes from @p, when p % 16 < 8 |
| * and p % 16 + s > 8. I.e. does not cross a 16-byte |
| * boundary, but *does* cross an 8-byte boundary. |
| * This is the slow version, so we must have eliminated |
| * any faster load_atom_extract_al8_or_exit case. |
| * |
| * If this is not possible, longjmp out to restart serially. |
| */ |
| static uint64_t load_atom_extract_al16_or_exit(CPUState *cpu, uintptr_t ra, |
| void *pv, int s) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int o = pi & 7; |
| int shr = (HOST_BIG_ENDIAN ? 16 - s - o : o) * 8; |
| Int128 r; |
| |
| /* |
| * Note constraints above: p & 8 must be clear. |
| * Provoke SIGBUS if possible otherwise. |
| */ |
| pv = (void *)(pi & ~7); |
| r = load_atomic16_or_exit(cpu, ra, pv); |
| |
| r = int128_urshift(r, shr); |
| return int128_getlo(r); |
| } |
| |
| /** |
| * load_atom_4_by_2: |
| * @pv: host address |
| * |
| * Load 4 bytes from @pv, with two 2-byte atomic loads. |
| */ |
| static inline uint32_t load_atom_4_by_2(void *pv) |
| { |
| uint32_t a = load_atomic2(pv); |
| uint32_t b = load_atomic2(pv + 2); |
| |
| if (HOST_BIG_ENDIAN) { |
| return (a << 16) | b; |
| } else { |
| return (b << 16) | a; |
| } |
| } |
| |
| /** |
| * load_atom_8_by_2: |
| * @pv: host address |
| * |
| * Load 8 bytes from @pv, with four 2-byte atomic loads. |
| */ |
| static inline uint64_t load_atom_8_by_2(void *pv) |
| { |
| uint32_t a = load_atom_4_by_2(pv); |
| uint32_t b = load_atom_4_by_2(pv + 4); |
| |
| if (HOST_BIG_ENDIAN) { |
| return ((uint64_t)a << 32) | b; |
| } else { |
| return ((uint64_t)b << 32) | a; |
| } |
| } |
| |
| /** |
| * load_atom_8_by_4: |
| * @pv: host address |
| * |
| * Load 8 bytes from @pv, with two 4-byte atomic loads. |
| */ |
| static inline uint64_t load_atom_8_by_4(void *pv) |
| { |
| uint32_t a = load_atomic4(pv); |
| uint32_t b = load_atomic4(pv + 4); |
| |
| if (HOST_BIG_ENDIAN) { |
| return ((uint64_t)a << 32) | b; |
| } else { |
| return ((uint64_t)b << 32) | a; |
| } |
| } |
| |
| /** |
| * load_atom_8_by_8_or_4: |
| * @pv: host address |
| * |
| * Load 8 bytes from aligned @pv, with at least 4-byte atomicity. |
| */ |
| static inline uint64_t load_atom_8_by_8_or_4(void *pv) |
| { |
| if (HAVE_al8_fast) { |
| return load_atomic8(pv); |
| } else { |
| return load_atom_8_by_4(pv); |
| } |
| } |
| |
| /** |
| * load_atom_2: |
| * @p: host address |
| * @memop: the full memory op |
| * |
| * Load 2 bytes from @p, honoring the atomicity of @memop. |
| */ |
| static uint16_t load_atom_2(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| |
| if (likely((pi & 1) == 0)) { |
| return load_atomic2(pv); |
| } |
| if (HAVE_ATOMIC128_RO) { |
| intptr_t left_in_page = -(pi | TARGET_PAGE_MASK); |
| if (likely(left_in_page > 8)) { |
| return load_atom_extract_al16_or_al8(pv, 2); |
| } |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| switch (atmax) { |
| case MO_8: |
| return lduw_he_p(pv); |
| case MO_16: |
| /* The only case remaining is MO_ATOM_WITHIN16. */ |
| if (!HAVE_al8_fast && (pi & 3) == 1) { |
| /* Big or little endian, we want the middle two bytes. */ |
| return load_atomic4(pv - 1) >> 8; |
| } |
| if ((pi & 15) != 7) { |
| return load_atom_extract_al8_or_exit(cpu, ra, pv, 2); |
| } |
| return load_atom_extract_al16_or_exit(cpu, ra, pv, 2); |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| |
| /** |
| * load_atom_4: |
| * @p: host address |
| * @memop: the full memory op |
| * |
| * Load 4 bytes from @p, honoring the atomicity of @memop. |
| */ |
| static uint32_t load_atom_4(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| |
| if (likely((pi & 3) == 0)) { |
| return load_atomic4(pv); |
| } |
| if (HAVE_ATOMIC128_RO) { |
| intptr_t left_in_page = -(pi | TARGET_PAGE_MASK); |
| if (likely(left_in_page > 8)) { |
| return load_atom_extract_al16_or_al8(pv, 4); |
| } |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| switch (atmax) { |
| case MO_8: |
| case MO_16: |
| case -MO_16: |
| /* |
| * For MO_ATOM_IFALIGN, this is more atomicity than required, |
| * but it's trivially supported on all hosts, better than 4 |
| * individual byte loads (when the host requires alignment), |
| * and overlaps with the MO_ATOM_SUBALIGN case of p % 2 == 0. |
| */ |
| return load_atom_extract_al4x2(pv); |
| case MO_32: |
| if (!(pi & 4)) { |
| return load_atom_extract_al8_or_exit(cpu, ra, pv, 4); |
| } |
| return load_atom_extract_al16_or_exit(cpu, ra, pv, 4); |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| |
| /** |
| * load_atom_8: |
| * @p: host address |
| * @memop: the full memory op |
| * |
| * Load 8 bytes from @p, honoring the atomicity of @memop. |
| */ |
| static uint64_t load_atom_8(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| |
| /* |
| * If the host does not support 8-byte atomics, wait until we have |
| * examined the atomicity parameters below. |
| */ |
| if (HAVE_al8 && likely((pi & 7) == 0)) { |
| return load_atomic8(pv); |
| } |
| if (HAVE_ATOMIC128_RO) { |
| return load_atom_extract_al16_or_al8(pv, 8); |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| if (atmax == MO_64) { |
| if (!HAVE_al8 && (pi & 7) == 0) { |
| load_atomic8_or_exit(cpu, ra, pv); |
| } |
| return load_atom_extract_al16_or_exit(cpu, ra, pv, 8); |
| } |
| if (HAVE_al8_fast) { |
| return load_atom_extract_al8x2(pv); |
| } |
| switch (atmax) { |
| case MO_8: |
| return ldq_he_p(pv); |
| case MO_16: |
| return load_atom_8_by_2(pv); |
| case MO_32: |
| return load_atom_8_by_4(pv); |
| case -MO_32: |
| if (HAVE_al8) { |
| return load_atom_extract_al8x2(pv); |
| } |
| cpu_loop_exit_atomic(cpu, ra); |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| |
| /** |
| * load_atom_16: |
| * @p: host address |
| * @memop: the full memory op |
| * |
| * Load 16 bytes from @p, honoring the atomicity of @memop. |
| */ |
| static Int128 load_atom_16(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| Int128 r; |
| uint64_t a, b; |
| |
| /* |
| * If the host does not support 16-byte atomics, wait until we have |
| * examined the atomicity parameters below. |
| */ |
| if (HAVE_ATOMIC128_RO && likely((pi & 15) == 0)) { |
| return atomic16_read_ro(pv); |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| switch (atmax) { |
| case MO_8: |
| memcpy(&r, pv, 16); |
| return r; |
| case MO_16: |
| a = load_atom_8_by_2(pv); |
| b = load_atom_8_by_2(pv + 8); |
| break; |
| case MO_32: |
| a = load_atom_8_by_4(pv); |
| b = load_atom_8_by_4(pv + 8); |
| break; |
| case MO_64: |
| if (!HAVE_al8) { |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
| a = load_atomic8(pv); |
| b = load_atomic8(pv + 8); |
| break; |
| case -MO_64: |
| if (!HAVE_al8) { |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
| a = load_atom_extract_al8x2(pv); |
| b = load_atom_extract_al8x2(pv + 8); |
| break; |
| case MO_128: |
| return load_atomic16_or_exit(cpu, ra, pv); |
| default: |
| g_assert_not_reached(); |
| } |
| return int128_make128(HOST_BIG_ENDIAN ? b : a, HOST_BIG_ENDIAN ? a : b); |
| } |
| |
| /** |
| * store_atomic2: |
| * @pv: host address |
| * @val: value to store |
| * |
| * Atomically store 2 aligned bytes to @pv. |
| */ |
| static inline void store_atomic2(void *pv, uint16_t val) |
| { |
| uint16_t *p = __builtin_assume_aligned(pv, 2); |
| qatomic_set(p, val); |
| } |
| |
| /** |
| * store_atomic4: |
| * @pv: host address |
| * @val: value to store |
| * |
| * Atomically store 4 aligned bytes to @pv. |
| */ |
| static inline void store_atomic4(void *pv, uint32_t val) |
| { |
| uint32_t *p = __builtin_assume_aligned(pv, 4); |
| qatomic_set(p, val); |
| } |
| |
| /** |
| * store_atomic8: |
| * @pv: host address |
| * @val: value to store |
| * |
| * Atomically store 8 aligned bytes to @pv. |
| */ |
| static inline void store_atomic8(void *pv, uint64_t val) |
| { |
| uint64_t *p = __builtin_assume_aligned(pv, 8); |
| |
| qemu_build_assert(HAVE_al8); |
| qatomic_set__nocheck(p, val); |
| } |
| |
| /** |
| * store_atom_4x2 |
| */ |
| static inline void store_atom_4_by_2(void *pv, uint32_t val) |
| { |
| store_atomic2(pv, val >> (HOST_BIG_ENDIAN ? 16 : 0)); |
| store_atomic2(pv + 2, val >> (HOST_BIG_ENDIAN ? 0 : 16)); |
| } |
| |
| /** |
| * store_atom_8_by_2 |
| */ |
| static inline void store_atom_8_by_2(void *pv, uint64_t val) |
| { |
| store_atom_4_by_2(pv, val >> (HOST_BIG_ENDIAN ? 32 : 0)); |
| store_atom_4_by_2(pv + 4, val >> (HOST_BIG_ENDIAN ? 0 : 32)); |
| } |
| |
| /** |
| * store_atom_8_by_4 |
| */ |
| static inline void store_atom_8_by_4(void *pv, uint64_t val) |
| { |
| store_atomic4(pv, val >> (HOST_BIG_ENDIAN ? 32 : 0)); |
| store_atomic4(pv + 4, val >> (HOST_BIG_ENDIAN ? 0 : 32)); |
| } |
| |
| /** |
| * store_atom_insert_al4: |
| * @p: host address |
| * @val: shifted value to store |
| * @msk: mask for value to store |
| * |
| * Atomically store @val to @p, masked by @msk. |
| */ |
| static void store_atom_insert_al4(uint32_t *p, uint32_t val, uint32_t msk) |
| { |
| uint32_t old, new; |
| |
| p = __builtin_assume_aligned(p, 4); |
| old = qatomic_read(p); |
| do { |
| new = (old & ~msk) | val; |
| } while (!__atomic_compare_exchange_n(p, &old, new, true, |
| __ATOMIC_RELAXED, __ATOMIC_RELAXED)); |
| } |
| |
| /** |
| * store_atom_insert_al8: |
| * @p: host address |
| * @val: shifted value to store |
| * @msk: mask for value to store |
| * |
| * Atomically store @val to @p masked by @msk. |
| */ |
| static void store_atom_insert_al8(uint64_t *p, uint64_t val, uint64_t msk) |
| { |
| uint64_t old, new; |
| |
| qemu_build_assert(HAVE_al8); |
| p = __builtin_assume_aligned(p, 8); |
| old = qatomic_read__nocheck(p); |
| do { |
| new = (old & ~msk) | val; |
| } while (!__atomic_compare_exchange_n(p, &old, new, true, |
| __ATOMIC_RELAXED, __ATOMIC_RELAXED)); |
| } |
| |
| /** |
| * store_bytes_leN: |
| * @pv: host address |
| * @size: number of bytes to store |
| * @val_le: data to store |
| * |
| * Store @size bytes at @p. The bytes to store are extracted in little-endian order |
| * from @val_le; return the bytes of @val_le beyond @size that have not been stored. |
| */ |
| static uint64_t store_bytes_leN(void *pv, int size, uint64_t val_le) |
| { |
| uint8_t *p = pv; |
| for (int i = 0; i < size; i++, val_le >>= 8) { |
| p[i] = val_le; |
| } |
| return val_le; |
| } |
| |
| /** |
| * store_parts_leN |
| * @pv: host address |
| * @size: number of bytes to store |
| * @val_le: data to store |
| * |
| * As store_bytes_leN, but atomically on each aligned part. |
| */ |
| G_GNUC_UNUSED |
| static uint64_t store_parts_leN(void *pv, int size, uint64_t val_le) |
| { |
| do { |
| int n; |
| |
| /* Find minimum of alignment and size */ |
| switch (((uintptr_t)pv | size) & 7) { |
| case 4: |
| store_atomic4(pv, le32_to_cpu(val_le)); |
| val_le >>= 32; |
| n = 4; |
| break; |
| case 2: |
| case 6: |
| store_atomic2(pv, le16_to_cpu(val_le)); |
| val_le >>= 16; |
| n = 2; |
| break; |
| default: |
| *(uint8_t *)pv = val_le; |
| val_le >>= 8; |
| n = 1; |
| break; |
| case 0: |
| g_assert_not_reached(); |
| } |
| pv += n; |
| size -= n; |
| } while (size != 0); |
| |
| return val_le; |
| } |
| |
| /** |
| * store_whole_le4 |
| * @pv: host address |
| * @size: number of bytes to store |
| * @val_le: data to store |
| * |
| * As store_bytes_leN, but atomically as a whole. |
| * Four aligned bytes are guaranteed to cover the store. |
| */ |
| static uint64_t store_whole_le4(void *pv, int size, uint64_t val_le) |
| { |
| int sz = size * 8; |
| int o = (uintptr_t)pv & 3; |
| int sh = o * 8; |
| uint32_t m = MAKE_64BIT_MASK(0, sz); |
| uint32_t v; |
| |
| if (HOST_BIG_ENDIAN) { |
| v = bswap32(val_le) >> sh; |
| m = bswap32(m) >> sh; |
| } else { |
| v = val_le << sh; |
| m <<= sh; |
| } |
| store_atom_insert_al4(pv - o, v, m); |
| return val_le >> sz; |
| } |
| |
| /** |
| * store_whole_le8 |
| * @pv: host address |
| * @size: number of bytes to store |
| * @val_le: data to store |
| * |
| * As store_bytes_leN, but atomically as a whole. |
| * Eight aligned bytes are guaranteed to cover the store. |
| */ |
| static uint64_t store_whole_le8(void *pv, int size, uint64_t val_le) |
| { |
| int sz = size * 8; |
| int o = (uintptr_t)pv & 7; |
| int sh = o * 8; |
| uint64_t m = MAKE_64BIT_MASK(0, sz); |
| uint64_t v; |
| |
| qemu_build_assert(HAVE_al8); |
| if (HOST_BIG_ENDIAN) { |
| v = bswap64(val_le) >> sh; |
| m = bswap64(m) >> sh; |
| } else { |
| v = val_le << sh; |
| m <<= sh; |
| } |
| store_atom_insert_al8(pv - o, v, m); |
| return val_le >> sz; |
| } |
| |
| /** |
| * store_whole_le16 |
| * @pv: host address |
| * @size: number of bytes to store |
| * @val_le: data to store |
| * |
| * As store_bytes_leN, but atomically as a whole. |
| * 16 aligned bytes are guaranteed to cover the store. |
| */ |
| static uint64_t store_whole_le16(void *pv, int size, Int128 val_le) |
| { |
| int sz = size * 8; |
| int o = (uintptr_t)pv & 15; |
| int sh = o * 8; |
| Int128 m, v; |
| |
| qemu_build_assert(HAVE_CMPXCHG128); |
| |
| /* Like MAKE_64BIT_MASK(0, sz), but larger. */ |
| if (sz <= 64) { |
| m = int128_make64(MAKE_64BIT_MASK(0, sz)); |
| } else { |
| m = int128_make128(-1, MAKE_64BIT_MASK(0, sz - 64)); |
| } |
| |
| if (HOST_BIG_ENDIAN) { |
| v = int128_urshift(bswap128(val_le), sh); |
| m = int128_urshift(bswap128(m), sh); |
| } else { |
| v = int128_lshift(val_le, sh); |
| m = int128_lshift(m, sh); |
| } |
| store_atom_insert_al16(pv - o, v, m); |
| |
| if (sz <= 64) { |
| return 0; |
| } |
| return int128_gethi(val_le) >> (sz - 64); |
| } |
| |
| /** |
| * store_atom_2: |
| * @p: host address |
| * @val: the value to store |
| * @memop: the full memory op |
| * |
| * Store 2 bytes to @p, honoring the atomicity of @memop. |
| */ |
| static void store_atom_2(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop, uint16_t val) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| |
| if (likely((pi & 1) == 0)) { |
| store_atomic2(pv, val); |
| return; |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| if (atmax == MO_8) { |
| stw_he_p(pv, val); |
| return; |
| } |
| |
| /* |
| * The only case remaining is MO_ATOM_WITHIN16. |
| * Big or little endian, we want the middle two bytes in each test. |
| */ |
| if ((pi & 3) == 1) { |
| store_atom_insert_al4(pv - 1, (uint32_t)val << 8, MAKE_64BIT_MASK(8, 16)); |
| return; |
| } else if ((pi & 7) == 3) { |
| if (HAVE_al8) { |
| store_atom_insert_al8(pv - 3, (uint64_t)val << 24, MAKE_64BIT_MASK(24, 16)); |
| return; |
| } |
| } else if ((pi & 15) == 7) { |
| if (HAVE_CMPXCHG128) { |
| Int128 v = int128_lshift(int128_make64(val), 56); |
| Int128 m = int128_lshift(int128_make64(0xffff), 56); |
| store_atom_insert_al16(pv - 7, v, m); |
| return; |
| } |
| } else { |
| g_assert_not_reached(); |
| } |
| |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
| |
| /** |
| * store_atom_4: |
| * @p: host address |
| * @val: the value to store |
| * @memop: the full memory op |
| * |
| * Store 4 bytes to @p, honoring the atomicity of @memop. |
| */ |
| static void store_atom_4(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop, uint32_t val) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| |
| if (likely((pi & 3) == 0)) { |
| store_atomic4(pv, val); |
| return; |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| switch (atmax) { |
| case MO_8: |
| stl_he_p(pv, val); |
| return; |
| case MO_16: |
| store_atom_4_by_2(pv, val); |
| return; |
| case -MO_16: |
| { |
| uint32_t val_le = cpu_to_le32(val); |
| int s2 = pi & 3; |
| int s1 = 4 - s2; |
| |
| switch (s2) { |
| case 1: |
| val_le = store_whole_le4(pv, s1, val_le); |
| *(uint8_t *)(pv + 3) = val_le; |
| break; |
| case 3: |
| *(uint8_t *)pv = val_le; |
| store_whole_le4(pv + 1, s2, val_le >> 8); |
| break; |
| case 0: /* aligned */ |
| case 2: /* atmax MO_16 */ |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| return; |
| case MO_32: |
| if ((pi & 7) < 4) { |
| if (HAVE_al8) { |
| store_whole_le8(pv, 4, cpu_to_le32(val)); |
| return; |
| } |
| } else { |
| if (HAVE_CMPXCHG128) { |
| store_whole_le16(pv, 4, int128_make64(cpu_to_le32(val))); |
| return; |
| } |
| } |
| cpu_loop_exit_atomic(cpu, ra); |
| default: |
| g_assert_not_reached(); |
| } |
| } |
| |
| /** |
| * store_atom_8: |
| * @p: host address |
| * @val: the value to store |
| * @memop: the full memory op |
| * |
| * Store 8 bytes to @p, honoring the atomicity of @memop. |
| */ |
| static void store_atom_8(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop, uint64_t val) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| int atmax; |
| |
| if (HAVE_al8 && likely((pi & 7) == 0)) { |
| store_atomic8(pv, val); |
| return; |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| switch (atmax) { |
| case MO_8: |
| stq_he_p(pv, val); |
| return; |
| case MO_16: |
| store_atom_8_by_2(pv, val); |
| return; |
| case MO_32: |
| store_atom_8_by_4(pv, val); |
| return; |
| case -MO_32: |
| if (HAVE_al8) { |
| uint64_t val_le = cpu_to_le64(val); |
| int s2 = pi & 7; |
| int s1 = 8 - s2; |
| |
| switch (s2) { |
| case 1 ... 3: |
| val_le = store_whole_le8(pv, s1, val_le); |
| store_bytes_leN(pv + s1, s2, val_le); |
| break; |
| case 5 ... 7: |
| val_le = store_bytes_leN(pv, s1, val_le); |
| store_whole_le8(pv + s1, s2, val_le); |
| break; |
| case 0: /* aligned */ |
| case 4: /* atmax MO_32 */ |
| default: |
| g_assert_not_reached(); |
| } |
| return; |
| } |
| break; |
| case MO_64: |
| if (HAVE_CMPXCHG128) { |
| store_whole_le16(pv, 8, int128_make64(cpu_to_le64(val))); |
| return; |
| } |
| break; |
| default: |
| g_assert_not_reached(); |
| } |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
| |
| /** |
| * store_atom_16: |
| * @p: host address |
| * @val: the value to store |
| * @memop: the full memory op |
| * |
| * Store 16 bytes to @p, honoring the atomicity of @memop. |
| */ |
| static void store_atom_16(CPUState *cpu, uintptr_t ra, |
| void *pv, MemOp memop, Int128 val) |
| { |
| uintptr_t pi = (uintptr_t)pv; |
| uint64_t a, b; |
| int atmax; |
| |
| if (HAVE_ATOMIC128_RW && likely((pi & 15) == 0)) { |
| atomic16_set(pv, val); |
| return; |
| } |
| |
| atmax = required_atomicity(cpu, pi, memop); |
| |
| a = HOST_BIG_ENDIAN ? int128_gethi(val) : int128_getlo(val); |
| b = HOST_BIG_ENDIAN ? int128_getlo(val) : int128_gethi(val); |
| switch (atmax) { |
| case MO_8: |
| memcpy(pv, &val, 16); |
| return; |
| case MO_16: |
| store_atom_8_by_2(pv, a); |
| store_atom_8_by_2(pv + 8, b); |
| return; |
| case MO_32: |
| store_atom_8_by_4(pv, a); |
| store_atom_8_by_4(pv + 8, b); |
| return; |
| case MO_64: |
| if (HAVE_al8) { |
| store_atomic8(pv, a); |
| store_atomic8(pv + 8, b); |
| return; |
| } |
| break; |
| case -MO_64: |
| if (HAVE_CMPXCHG128) { |
| uint64_t val_le; |
| int s2 = pi & 15; |
| int s1 = 16 - s2; |
| |
| if (HOST_BIG_ENDIAN) { |
| val = bswap128(val); |
| } |
| switch (s2) { |
| case 1 ... 7: |
| val_le = store_whole_le16(pv, s1, val); |
| store_bytes_leN(pv + s1, s2, val_le); |
| break; |
| case 9 ... 15: |
| store_bytes_leN(pv, s1, int128_getlo(val)); |
| val = int128_urshift(val, s1 * 8); |
| store_whole_le16(pv + s1, s2, val); |
| break; |
| case 0: /* aligned */ |
| case 8: /* atmax MO_64 */ |
| default: |
| g_assert_not_reached(); |
| } |
| return; |
| } |
| break; |
| case MO_128: |
| break; |
| default: |
| g_assert_not_reached(); |
| } |
| cpu_loop_exit_atomic(cpu, ra); |
| } |
