path: root/accel/tcg/cputlb.c

/*
 *  Common CPU TLB handling
 *
 *  Copyright (c) 2003 Fabrice Bellard
 *
 * 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 2.1 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/>.
 */

#include "qemu/osdep.h"
#include "qemu/main-loop.h"
#include "hw/core/tcg-cpu-ops.h"
#include "exec/exec-all.h"
#include "exec/memory.h"
#include "exec/cpu_ldst.h"
#include "exec/cputlb.h"
#include "exec/memory-internal.h"
#include "exec/ram_addr.h"
#include "tcg/tcg.h"
#include "qemu/error-report.h"
#include "exec/log.h"
#include "exec/helper-proto.h"
#include "qemu/atomic.h"
#include "qemu/atomic128.h"
#include "exec/translate-all.h"
#include "trace/trace-root.h"
#include "tb-hash.h"
#include "internal.h"
#ifdef CONFIG_PLUGIN
#include "qemu/plugin-memory.h"
#endif
#include "tcg/tcg-ldst.h"

/* DEBUG defines, enable DEBUG_TLB_LOG to log to the CPU_LOG_MMU target */
/* #define DEBUG_TLB */
/* #define DEBUG_TLB_LOG */

#ifdef DEBUG_TLB
# define DEBUG_TLB_GATE 1
# ifdef DEBUG_TLB_LOG
#  define DEBUG_TLB_LOG_GATE 1
# else
#  define DEBUG_TLB_LOG_GATE 0
# endif
#else
# define DEBUG_TLB_GATE 0
# define DEBUG_TLB_LOG_GATE 0
#endif

#define tlb_debug(fmt, ...) do { \
    if (DEBUG_TLB_LOG_GATE) { \
        qemu_log_mask(CPU_LOG_MMU, "%s: " fmt, __func__, \
                      ## __VA_ARGS__); \
    } else if (DEBUG_TLB_GATE) { \
        fprintf(stderr, "%s: " fmt, __func__, ## __VA_ARGS__); \
    } \
} while (0)

#define assert_cpu_is_self(cpu) do {                              \
        if (DEBUG_TLB_GATE) {                                     \
            g_assert(!(cpu)->created || qemu_cpu_is_self(cpu));   \
        }                                                         \
    } while (0)

/* run_on_cpu_data.target_ptr should always be big enough for a
 * target_ulong even on 32 bit builds */
QEMU_BUILD_BUG_ON(sizeof(target_ulong) > sizeof(run_on_cpu_data));

/* We currently can't handle more than 16 bits in the MMUIDX bitmask.
 */
QEMU_BUILD_BUG_ON(NB_MMU_MODES > 16);
#define ALL_MMUIDX_BITS ((1 << NB_MMU_MODES) - 1)

static inline size_t tlb_n_entries(CPUTLBDescFast *fast)
{
    return (fast->mask >> CPU_TLB_ENTRY_BITS) + 1;
}

static inline size_t sizeof_tlb(CPUTLBDescFast *fast)
{
    return fast->mask + (1 << CPU_TLB_ENTRY_BITS);
}

static void tlb_window_reset(CPUTLBDesc *desc, int64_t ns,
                             size_t max_entries)
{
    desc->window_begin_ns = ns;
    desc->window_max_entries = max_entries;
}

static void tb_jmp_cache_clear_page(CPUState *cpu, target_ulong page_addr)
{
    unsigned int i, i0 = tb_jmp_cache_hash_page(page_addr);

    for (i = 0; i < TB_JMP_PAGE_SIZE; i++) {
        qatomic_set(&cpu->tb_jmp_cache[i0 + i], NULL);
    }
}

static void tb_flush_jmp_cache(CPUState *cpu, target_ulong addr)
{
    /* Discard jump cache entries for any tb which might potentially
       overlap the flushed page.  */
    tb_jmp_cache_clear_page(cpu, addr - TARGET_PAGE_SIZE);
    tb_jmp_cache_clear_page(cpu, addr);
}

/**
 * tlb_mmu_resize_locked() - perform TLB resize bookkeeping; resize if necessary
 * @desc: The CPUTLBDesc portion of the TLB
 * @fast: The CPUTLBDescFast portion of the same TLB
 *
 * Called with tlb_lock_held.
 *
 * We have two main constraints when resizing a TLB: (1) we only resize it
 * on a TLB flush (otherwise we'd have to take a perf hit by either rehashing
 * the array or unnecessarily flushing it), which means we do not control how
 * frequently the resizing can occur; (2) we don't have access to the guest's
 * future scheduling decisions, and therefore have to decide the magnitude of
 * the resize based on past observations.
 *
 * In general, a memory-hungry process can benefit greatly from an appropriately
 * sized TLB, since a guest TLB miss is very expensive. This doesn't mean that
 * we just have to make the TLB as large as possible; while an oversized TLB
 * results in minimal TLB miss rates, it also takes longer to be flushed
 * (flushes can be _very_ frequent), and the reduced locality can also hurt
 * performance.
 *
 * To achieve near-optimal performance for all kinds of workloads, we:
 *
 * 1. Aggressively increase the size of the TLB when the use rate of the
 * TLB being flushed is high, since it is likely that in the near future this
 * memory-hungry process will execute again, and its memory hungriness will
 * probably be similar.
 *
 * 2. Slowly reduce the size of the TLB as the use rate declines over a
 * reasonably large time window. The rationale is that if in such a time window
 * we have not observed a high TLB use rate, it is likely that we won't observe
 * it in the near future. In that case, once a time window expires we downsize
 * the TLB to match the maximum use rate observed in the window.
 *
 * 3. Try to keep the maximum use rate in a time window in the 30-70% range,
 * since in that range performance is likely near-optimal. Recall that the TLB
 * is direct mapped, so we want the use rate to be low (or at least not too
 * high), since otherwise we are likely to have a significant amount of
 * conflict misses.
 */
static void tlb_mmu_resize_locked(CPUTLBDesc *desc, CPUTLBDescFast *fast,
                                  int64_t now)
{
    size_t old_size = tlb_n_entries(fast);
    size_t rate;
    size_t new_size = old_size;
    int64_t window_len_ms = 100;
    int64_t window_len_ns = window_len_ms * 1000 * 1000;
    bool window_expired = now > desc->window_begin_ns + window_len_ns;

    if (desc->n_used_entries > desc->window_max_entries) {
        desc->window_max_entries = desc->n_used_entries;
    }
    rate = desc->window_max_entries * 100 / old_size;

    if (rate > 70) {
        new_size = MIN(old_size << 1, 1 << CPU_TLB_DYN_MAX_BITS);
    } else if (rate < 30 && window_expired) {
        size_t ceil = pow2ceil(desc->window_max_entries);
        size_t expected_rate = desc->window_max_entries * 100 / ceil;

        /*
         * Avoid undersizing when the max number of entries seen is just below
         * a pow2. For instance, if max_entries == 1025, the expected use rate
         * would be 1025/2048==50%. However, if max_entries == 1023, we'd get
         * 1023/1024==99.9% use rate, so we'd likely end up doubling the size
         * later. Thus, make sure that the expected use rate remains below 70%.
         * (and since we double the size, that means the lowest rate we'd
         * expect to get is 35%, which is still in the 30-70% range where
         * we consider that the size is appropriate.)
         */
        if (expected_rate > 70) {
            ceil *= 2;
        }
        new_size = MAX(ceil, 1 << CPU_TLB_DYN_MIN_BITS);
    }

    if (new_size == old_size) {
        if (window_expired) {
            tlb_window_reset(desc, now, desc->n_used_entries);
        }
        return;
    }

    g_free(fast->table);
    g_free(desc->fulltlb);

    tlb_window_reset(desc, now, 0);
    /* desc->n_used_entries is cleared by the caller */
    fast->mask = (new_size - 1) << CPU_TLB_ENTRY_BITS;
    fast->table = g_try_new(CPUTLBEntry, new_size);
    desc->fulltlb = g_try_new(CPUTLBEntryFull, new_size);

    /*
     * If the allocations fail, try smaller sizes. We just freed some
     * memory, so going back to half of new_size has a good chance of working.
     * Increased memory pressure elsewhere in the system might cause the
     * allocations to fail though, so we progressively reduce the allocation
     * size, aborting if we cannot even allocate the smallest TLB we support.
     */
    while (fast->table == NULL || desc->fulltlb == NULL) {
        if (new_size == (1 << CPU_TLB_DYN_MIN_BITS)) {
            error_report("%s: %s", __func__, strerror(errno));
            abort();
        }
        new_size = MAX(new_size >> 1, 1 << CPU_TLB_DYN_MIN_BITS);
        fast->mask = (new_size - 1) << CPU_TLB_ENTRY_BITS;

        g_free(fast->table);
        g_free(desc->fulltlb);
        fast->table = g_try_new(CPUTLBEntry, new_size);
        desc->fulltlb = g_try_new(CPUTLBEntryFull, new_size);
    }
}

static void tlb_mmu_flush_locked(CPUTLBDesc *desc, CPUTLBDescFast *fast)
{
    desc->n_used_entries = 0;
    desc->large_page_addr = -1;
    desc->large_page_mask = -1;
    desc->vindex = 0;
    memset(fast->table, -1, sizeof_tlb(fast));
    memset(desc->vtable, -1, sizeof(desc->vtable));
}

static void tlb_flush_one_mmuidx_locked(CPUArchState *env, int mmu_idx,
                                        int64_t now)
{
    CPUTLBDesc *desc = &env_tlb(env)->d[mmu_idx];
    CPUTLBDescFast *fast = &env_tlb(env)->f[mmu_idx];

    tlb_mmu_resize_locked(desc, fast, now);
    tlb_mmu_flush_locked(desc, fast);
}

static void tlb_mmu_init(CPUTLBDesc *desc, CPUTLBDescFast *fast, int64_t now)
{
    size_t n_entries = 1 << CPU_TLB_DYN_DEFAULT_BITS;

    tlb_window_reset(desc, now, 0);
    desc->n_used_entries = 0;
    fast->mask = (n_entries - 1) << CPU_TLB_ENTRY_BITS;
    fast->table = g_new(CPUTLBEntry, n_entries);
    desc->fulltlb = g_new(CPUTLBEntryFull, n_entries);
    tlb_mmu_flush_locked(desc, fast);
}

static inline void tlb_n_used_entries_inc(CPUArchState *env, uintptr_t mmu_idx)
{
    env_tlb(env)->d[mmu_idx].n_used_entries++;
}

static inline void tlb_n_used_entries_dec(CPUArchState *env, uintptr_t mmu_idx)
{
    env_tlb(env)->d[mmu_idx].n_used_entries--;
}

void tlb_init(CPUState *cpu)
{
    CPUArchState *env = cpu->env_ptr;
    int64_t now = get_clock_realtime();
    int i;

    qemu_spin_init(&env_tlb(env)->c.lock);

    /* All tlbs are initialized flushed. */
    env_tlb(env)->c.dirty = 0;

    for (i = 0; i < NB_MMU_MODES; i++) {
        tlb_mmu_init(&env_tlb(env)->d[i], &env_tlb(env)->f[i], now);
    }
}

void tlb_destroy(CPUState *cpu)
{
    CPUArchState *env = cpu->env_ptr;
    int i;

    qemu_spin_destroy(&env_tlb(env)->c.lock);
    for (i = 0; i < NB_MMU_MODES; i++) {
        CPUTLBDesc *desc = &env_tlb(env)->d[i];
        CPUTLBDescFast *fast = &env_tlb(env)->f[i];

        g_free(fast->table);
        g_free(desc->fulltlb);
    }
}

/* flush_all_helper: run fn across all cpus
 *
 * If the wait flag is set then the src cpu's helper will be queued as
 * "safe" work and the loop exited creating a synchronisation point
 * where all queued work will be finished before execution starts
 * again.
 */
static void flush_all_helper(CPUState *src, run_on_cpu_func fn,
                             run_on_cpu_data d)
{
    CPUState *cpu;

    CPU_FOREACH(cpu) {
        if (cpu != src) {
            async_run_on_cpu(cpu, fn, d);
        }
    }
}

void tlb_flush_counts(size_t *pfull, size_t *ppart, size_t *pelide)
{
    CPUState *cpu;
    size_t full = 0, part = 0, elide = 0;

    CPU_FOREACH(cpu) {
        CPUArchState *env = cpu->env_ptr;

        full += qatomic_read(&env_tlb(env)->c.full_flush_count);
        part += qatomic_read(&env_tlb(env)->c.part_flush_count);
        elide += qatomic_read(&env_tlb(env)->c.elide_flush_count);
    }
    *pfull = full;
    *ppart = part;
    *pelide = elide;
}

static void tlb_flush_by_mmuidx_async_work(CPUState *cpu, run_on_cpu_data data)
{
    CPUArchState *env = cpu->env_ptr;
    uint16_t asked = data.host_int;
    uint16_t all_dirty, work, to_clean;
    int64_t now = get_clock_realtime();

    assert_cpu_is_self(cpu);

    tlb_debug("mmu_idx:0x%04" PRIx16 "\n", asked);

    qemu_spin_lock(&env_tlb(env)->c.lock);

    all_dirty = env_tlb(env)->c.dirty;
    to_clean = asked & all_dirty;
    all_dirty &= ~to_clean;
    env_tlb(env)->c.dirty = all_dirty;

    for (work = to_clean; work != 0; work &= work - 1) {
        int mmu_idx = ctz32(work);
        tlb_flush_one_mmuidx_locked(env, mmu_idx, now);
    }

    qemu_spin_unlock(&env_tlb(env)->c.lock);

    cpu_tb_jmp_cache_clear(cpu);

    if (to_clean == ALL_MMUIDX_BITS) {
        qatomic_set(&env_tlb(env)->c.full_flush_count,
                   env_tlb(env)->c.full_flush_count + 1);
    } else {
        qatomic_set(&env_tlb(env)->c.part_flush_count,
                   env_tlb(env)->c.part_flush_count + ctpop16(to_clean));
        if (to_clean != asked) {
            qatomic_set(&env_tlb(env)->c.elide_flush_count,
                       env_tlb(env)->c.elide_flush_count +
                       ctpop16(asked & ~to_clean));
        }
    }
}

void tlb_flush_by_mmuidx(CPUState *cpu, uint16_t idxmap)
{
    tlb_debug("mmu_idx: 0x%" PRIx16 "\n", idxmap);

    if (cpu->created && !qemu_cpu_is_self(cpu)) {
        async_run_on_cpu(cpu, tlb_flush_by_mmuidx_async_work,
                         RUN_ON_CPU_HOST_INT(idxmap));
    } else {
        tlb_flush_by_mmuidx_async_work(cpu, RUN_ON_CPU_HOST_INT(idxmap));
    }
}

void tlb_flush(CPUState *cpu)
{
    tlb_flush_by_mmuidx(cpu, ALL_MMUIDX_BITS);
}

void tlb_flush_by_mmuidx_all_cpus(CPUState *src_cpu, uint16_t idxmap)
{
    const run_on_cpu_func fn = tlb_flush_by_mmuidx_async_work;

    tlb_debug("mmu_idx: 0x%"PRIx16"\n", idxmap);

    flush_all_helper(src_cpu, fn, RUN_ON_CPU_HOST_INT(idxmap));
    fn(src_cpu, RUN_ON_CPU_HOST_INT(idxmap));
}

void tlb_flush_all_cpus(CPUState *src_cpu)
{
    tlb_flush_by_mmuidx_all_cpus(src_cpu, ALL_MMUIDX_BITS);
}

void tlb_flush_by_mmuidx_all_cpus_synced(CPUState *src_cpu, uint16_t idxmap)
{
    const run_on_cpu_func fn = tlb_flush_by_mmuidx_async_work;

    tlb_debug("mmu_idx: 0x%"PRIx16"\n", idxmap);

    flush_all_helper(src_cpu, fn, RUN_ON_CPU_HOST_INT(idxmap));
    async_safe_run_on_cpu(src_cpu, fn, RUN_ON_CPU_HOST_INT(idxmap));
}

void tlb_flush_all_cpus_synced(CPUState *src_cpu)
{
    tlb_flush_by_mmuidx_all_cpus_synced(src_cpu, ALL_MMUIDX_BITS);
}

static bool tlb_hit_page_mask_anyprot(CPUTLBEntry *tlb_entry,
                                      target_ulong page, target_ulong mask)
{
    page &= mask;
    mask &= TARGET_PAGE_MASK | TLB_INVALID_MASK;

    return (page == (tlb_entry->addr_read & mask) ||
            page == (tlb_addr_write(tlb_entry) & mask) ||
            page == (tlb_entry->addr_code & mask));
}

static inline bool tlb_hit_page_anyprot(CPUTLBEntry *tlb_entry,
                                        target_ulong page)
{
    return tlb_hit_page_mask_anyprot(tlb_entry, page, -1);
}

/**
 * tlb_entry_is_empty - return true if the entry is not in use
 * @te: pointer to CPUTLBEntry
 */
static inline bool tlb_entry_is_empty(const CPUTLBEntry *te)
{
    return te->addr_read == -1 && te->addr_write == -1 && te->addr_code == -1;
}

/* Called with tlb_c.lock held */
static bool tlb_flush_entry_mask_locked(CPUTLBEntry *tlb_entry,
                                        target_ulong page,
                                        target_ulong mask)
{
    if (tlb_hit_page_mask_anyprot(tlb_entry, page, mask)) {
        memset(tlb_entry, -1, sizeof(*tlb_entry));
        return true;
    }
    return false;
}

static inline bool tlb_flush_entry_locked(CPUTLBEntry *tlb_entry,
                                          target_ulong page)
{
    return tlb_flush_entry_mask_locked(tlb_entry, page, -1);
}

/* Called with tlb_c.lock held */
static void tlb_flush_vtlb_page_mask_locked(CPUArchState *env, int mmu_idx,
                                            target_ulong page,
                                            target_ulong mask)
{
    CPUTLBDesc *d = &env_tlb(env)->d[mmu_idx];
    int k;

    assert_cpu_is_self(env_cpu(env));
    for (k = 0; k < CPU_VTLB_SIZE; k++) {
        if (tlb_flush_entry_mask_locked(&d->vtable[k], page, mask)) {
            tlb_n_used_entries_dec(env, mmu_idx);
        }
    }
}

static inline void tlb_flush_vtlb_page_locked(CPUArchState *env, int mmu_idx,
                                              target_ulong page)
{
    tlb_flush_vtlb_page_mask_locked(env, mmu_idx, page, -1);
}

static void tlb_flush_page_locked(CPUArchState *env, int midx,
                                  target_ulong page)
{
    target_ulong lp_addr = env_tlb(env)->d[midx].large_page_addr;
    target_ulong lp_mask = env_tlb(env)->d[midx].large_page_mask;

    /* Check if we need to flush due to large pages.  */
    if ((page & lp_mask) == lp_addr) {
        tlb_debug("forcing full flush midx %d ("
                  TARGET_FMT_lx "/" TARGET_FMT_lx ")\n",
                  midx, lp_addr, lp_mask);
        tlb_flush_one_mmuidx_locked(env, midx, get_clock_realtime());
    } else {
        if (tlb_flush_entry_locked(tlb_entry(env, midx, page), page)) {
            tlb_n_used_entries_dec(env, midx);
        }
        tlb_flush_vtlb_page_locked(env, midx, page);
    }
}

/**
 * tlb_flush_page_by_mmuidx_async_0:
 * @cpu: cpu on which to flush
 * @addr: page of virtual address to flush
 * @idxmap: set of mmu_idx to flush
 *
 * Helper for tlb_flush_page_by_mmuidx and friends, flush one page
 * at @addr from the tlbs indicated by @idxmap from @cpu.
 */
static void tlb_flush_page_by_mmuidx_async_0(CPUState *cpu,
                                             target_ulong addr,
                                             uint16_t idxmap)
{
    CPUArchState *env = cpu->env_ptr;
    int mmu_idx;

    assert_cpu_is_self(cpu);

    tlb_debug("page addr:" TARGET_FMT_lx " mmu_map:0x%x\n", addr, idxmap);

    qemu_spin_lock(&env_tlb(env)->c.lock);
    for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
        if ((idxmap >> mmu_idx) & 1) {
            tlb_flush_page_locked(env, mmu_idx, addr);
        }
    }
    qemu_spin_unlock(&env_tlb(env)->c.lock);

    tb_flush_jmp_cache(cpu, addr);
}

/**
 * tlb_flush_page_by_mmuidx_async_1:
 * @cpu: cpu on which to flush
 * @data: encoded addr + idxmap
 *
 * Helper for tlb_flush_page_by_mmuidx and friends, called through
 * async_run_on_cpu.  The idxmap parameter is encoded in the page
 * offset of the target_ptr field.  This limits the set of mmu_idx
 * that can be passed via this method.
 */
static void tlb_flush_page_by_mmuidx_async_1(CPUState *cpu,
                                             run_on_cpu_data data)
{
    target_ulong addr_and_idxmap = (target_ulong) data.target_ptr;
    target_ulong addr = addr_and_idxmap & TARGET_PAGE_MASK;
    uint16_t idxmap = addr_and_idxmap & ~TARGET_PAGE_MASK;

    tlb_flush_page_by_mmuidx_async_0(cpu, addr, idxmap);
}

typedef struct {
    target_ulong addr;
    uint16_t idxmap;
} TLBFlushPageByMMUIdxData;

/**
 * tlb_flush_page_by_mmuidx_async_2:
 * @cpu: cpu on which to flush
 * @data: allocated addr + idxmap
 *
 * Helper for tlb_flush_page_by_mmuidx and friends, called through
 * async_run_on_cpu.  The addr+idxmap parameters are stored in a
 * TLBFlushPageByMMUIdxData structure that has been allocated
 * specifically for this helper.  Free the structure when done.
 */
static void tlb_flush_page_by_mmuidx_async_2(CPUState *cpu,
                                             run_on_cpu_data data)
{
    TLBFlushPageByMMUIdxData *d = data.host_ptr;

    tlb_flush_page_by_mmuidx_async_0(cpu, d->addr, d->idxmap);
    g_free(d);
}

void tlb_flush_page_by_mmuidx(CPUState *cpu, target_ulong addr, uint16_t idxmap)
{
    tlb_debug("addr: "TARGET_FMT_lx" mmu_idx:%" PRIx16 "\n", addr, idxmap);

    /* This should already be page aligned */
    addr &= TARGET_PAGE_MASK;

    if (qemu_cpu_is_self(cpu)) {
        tlb_flush_page_by_mmuidx_async_0(cpu, addr, idxmap);
    } else if (idxmap < TARGET_PAGE_SIZE) {
        /*
         * Most targets have only a few mmu_idx.  In the case where
         * we can stuff idxmap into the low TARGET_PAGE_BITS, avoid
         * allocating memory for this operation.
         */
        async_run_on_cpu(cpu, tlb_flush_page_by_mmuidx_async_1,
                         RUN_ON_CPU_TARGET_PTR(addr | idxmap));
    } else {
        TLBFlushPageByMMUIdxData *d = g_new(TLBFlushPageByMMUIdxData, 1);

        /* Otherwise allocate a structure, freed by the worker.  */
        d->addr = addr;
        d->idxmap = idxmap;
        async_run_on_cpu(cpu, tlb_flush_page_by_mmuidx_async_2,
                         RUN_ON_CPU_HOST_PTR(d));
    }
}

void tlb_flush_page(CPUState *cpu, target_ulong addr)
{
    tlb_flush_page_by_mmuidx(cpu, addr, ALL_MMUIDX_BITS);
}

void tlb_flush_page_by_mmuidx_all_cpus(CPUState *src_cpu, target_ulong addr,
                                       uint16_t idxmap)
{
    tlb_debug("addr: "TARGET_FMT_lx" mmu_idx:%"PRIx16"\n", addr, idxmap);

    /* This should already be page aligned */
    addr &= TARGET_PAGE_MASK;

    /*
     * Allocate memory to hold addr+idxmap only when needed.
     * See tlb_flush_page_by_mmuidx for details.
     */
    if (idxmap < TARGET_PAGE_SIZE) {
        flush_all_helper(src_cpu, tlb_flush_page_by_mmuidx_async_1,
                         RUN_ON_CPU_TARGET_PTR(addr | idxmap));
    } else {
        CPUState *dst_cpu;

        /* Allocate a separate data block for each destination cpu.  */
        CPU_FOREACH(dst_cpu) {
            if (dst_cpu != src_cpu) {
                TLBFlushPageByMMUIdxData *d
                    = g_new(TLBFlushPageByMMUIdxData, 1);

                d->addr = addr;
                d->idxmap = idxmap;
                async_run_on_cpu(dst_cpu, tlb_flush_page_by_mmuidx_async_2,
                                 RUN_ON_CPU_HOST_PTR(d));
            }
        }
    }

    tlb_flush_page_by_mmuidx_async_0(src_cpu, addr, idxmap);
}

void tlb_flush_page_all_cpus(CPUState *src, target_ulong addr)
{
    tlb_flush_page_by_mmuidx_all_cpus(src, addr, ALL_MMUIDX_BITS);
}

void tlb_flush_page_by_mmuidx_all_cpus_synced(CPUState *src_cpu,
                                              target_ulong addr,
                                              uint16_t idxmap)
{
    tlb_debug("addr: "TARGET_FMT_lx" mmu_idx:%"PRIx16"\n", addr, idxmap);

    /* This should already be page aligned */
    addr &= TARGET_PAGE_MASK;

    /*
     * Allocate memory to hold addr+idxmap only when needed.
     * See tlb_flush_page_by_mmuidx for details.
     */
    if (idxmap < TARGET_PAGE_SIZE) {
        flush_all_helper(src_cpu, tlb_flush_page_by_mmuidx_async_1,
                         RUN_ON_CPU_TARGET_PTR(addr | idxmap));
        async_safe_run_on_cpu(src_cpu, tlb_flush_page_by_mmuidx_async_1,
                              RUN_ON_CPU_TARGET_PTR(addr | idxmap));
    } else {
        CPUState *dst_cpu;
        TLBFlushPageByMMUIdxData *d;

        /* Allocate a separate data block for each destination cpu.  */
        CPU_FOREACH(dst_cpu) {
            if (dst_cpu != src_cpu) {
                d = g_new(TLBFlushPageByMMUIdxData, 1);
                d->addr = addr;
                d->idxmap = idxmap;
                async_run_on_cpu(dst_cpu, tlb_flush_page_by_mmuidx_async_2,
                                 RUN_ON_CPU_HOST_PTR(d));
            }
        }

        d = g_new(TLBFlushPageByMMUIdxData, 1);
        d->addr = addr;
        d->idxmap = idxmap;
        async_safe_run_on_cpu(src_cpu, tlb_flush_page_by_mmuidx_async_2,
                              RUN_ON_CPU_HOST_PTR(d));
    }
}

void tlb_flush_page_all_cpus_synced(CPUState *src, target_ulong addr)
{
    tlb_flush_page_by_mmuidx_all_cpus_synced(src, addr, ALL_MMUIDX_BITS);
}

static void tlb_flush_range_locked(CPUArchState *env, int midx,
                                   target_ulong addr, target_ulong len,
                                   unsigned bits)
{
    CPUTLBDesc *d = &env_tlb(env)->d[midx];
    CPUTLBDescFast *f = &env_tlb(env)->f[midx];
    target_ulong mask = MAKE_64BIT_MASK(0, bits);

    /*
     * If @bits is smaller than the tlb size, there may be multiple entries
     * within the TLB; otherwise all addresses that match under @mask hit
     * the same TLB entry.
     * TODO: Perhaps allow bits to be a few bits less than the size.
     * For now, just flush the entire TLB.
     *
     * If @len is larger than the tlb size, then it will take longer to
     * test all of the entries in the TLB than it will to flush it all.
     */
    if (mask < f->mask || len > f->mask) {
        tlb_debug("forcing full flush midx %d ("
                  TARGET_FMT_lx "/" TARGET_FMT_lx "+" TARGET_FMT_lx ")\n",
                  midx, addr, mask, len);
        tlb_flush_one_mmuidx_locked(env, midx, get_clock_realtime());
        return;
    }

    /*
     * Check if we need to flush due to large pages.
     * Because large_page_mask contains all 1's from the msb,
     * we only need to test the end of the range.
     */
    if (((addr + len - 1) & d->large_page_mask) == d->large_page_addr) {
        tlb_debug("forcing full flush midx %d ("
                  TARGET_FMT_lx "/" TARGET_FMT_lx ")\n",
                  midx, d->large_page_addr, d->large_page_mask);
        tlb_flush_one_mmuidx_locked(env, midx, get_clock_realtime());
        return;
    }

    for (target_ulong i = 0; i < len; i += TARGET_PAGE_SIZE) {
        target_ulong page = addr + i;
        CPUTLBEntry *entry = tlb_entry(env, midx, page);

        if (tlb_flush_entry_mask_locked(entry, page, mask)) {
            tlb_n_used_entries_dec(env, midx);
        }
        tlb_flush_vtlb_page_mask_locked(env, midx, page, mask);
    }
}

typedef struct {
    target_ulong addr;
    target_ulong len;
    uint16_t idxmap;
    uint16_t bits;
} TLBFlushRangeData;

static void tlb_flush_range_by_mmuidx_async_0(CPUState *cpu,
                                              TLBFlushRangeData d)
{
    CPUArchState *env = cpu->env_ptr;
    int mmu_idx;

    assert_cpu_is_self(cpu);

    tlb_debug("range:" TARGET_FMT_lx "/%u+" TARGET_FMT_lx " mmu_map:0x%x\n",
              d.addr, d.bits, d.len, d.idxmap);

    qemu_spin_lock(&env_tlb(env)->c.lock);
    for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
        if ((d.idxmap >> mmu_idx) & 1) {
            tlb_flush_range_locked(env, mmu_idx, d.addr, d.len, d.bits);
        }
    }
    qemu_spin_unlock(&env_tlb(env)->c.lock);

    /*
     * If the length is larger than the jump cache size, then it will take
     * longer to clear each entry individually than it will to clear it all.
     */
    if (d.len >= (TARGET_PAGE_SIZE * TB_JMP_CACHE_SIZE)) {
        cpu_tb_jmp_cache_clear(cpu);
        return;
    }

    for (target_ulong i = 0; i < d.len; i += TARGET_PAGE_SIZE) {
        tb_flush_jmp_cache(cpu, d.addr + i);
    }
}

static void tlb_flush_range_by_mmuidx_async_1(CPUState *cpu,
                                              run_on_cpu_data data)
{
    TLBFlushRangeData *d = data.host_ptr;
    tlb_flush_range_by_mmuidx_async_0(cpu, *d);
    g_free(d);
}

void tlb_flush_range_by_mmuidx(CPUState *cpu, target_ulong addr,
                               target_ulong len, uint16_t idxmap,
                               unsigned bits)
{
    TLBFlushRangeData d;

    /*
     * If all bits are significant, and len is small,
     * this devolves to tlb_flush_page.
     */
    if (bits >= TARGET_LONG_BITS && len <= TARGET_PAGE_SIZE) {
        tlb_flush_page_by_mmuidx(cpu, addr, idxmap);
        return;
    }
    /* If no page bits are significant, this devolves to tlb_flush. */
    if (bits < TARGET_PAGE_BITS) {
        tlb_flush_by_mmuidx(cpu, idxmap);
        return;
    }

    /* This should already be page aligned */
    d.addr = addr & TARGET_PAGE_MASK;
    d.len = len;
    d.idxmap = idxmap;
    d.bits = bits;

    if (qemu_cpu_is_self(cpu)) {
        tlb_flush_range_by_mmuidx_async_0(cpu, d);
    } else {
        /* Otherwise allocate a structure, freed by the worker.  */
        TLBFlushRangeData *p = g_memdup(&d, sizeof(d));
        async_run_on_cpu(cpu, tlb_flush_range_by_mmuidx_async_1,
                         RUN_ON_CPU_HOST_PTR(p));
    }
}

void tlb_flush_page_bits_by_mmuidx(CPUState *cpu, target_ulong addr,
                                   uint16_t idxmap, unsigned bits)
{
    tlb_flush_range_by_mmuidx(cpu, addr, TARGET_PAGE_SIZE, idxmap, bits);
}

void tlb_flush_range_by_mmuidx_all_cpus(CPUState *src_cpu,
                                        target_ulong addr, target_ulong len,
                                        uint16_t idxmap, unsigned bits)
{
    TLBFlushRangeData d;
    CPUState *dst_cpu;

    /*
     * If all bits are significant, and len is small,
     * this devolves to tlb_flush_page.
     */
    if (bits >= TARGET_LONG_BITS && len <= TARGET_PAGE_SIZE) {
        tlb_flush_page_by_mmuidx_all_cpus(src_cpu, addr, idxmap);
        return;
    }
    /* If no page bits are significant, this devolves to tlb_flush. */
    if (bits < TARGET_PAGE_BITS) {
        tlb_flush_by_mmuidx_all_cpus(src_cpu, idxmap);
        return;
    }

    /* This should already be page aligned */
    d.addr = addr & TARGET_PAGE_MASK;
    d.len = len;
    d.idxmap = idxmap;
    d.bits = bits;

    /* Allocate a separate data block for each destination cpu.  */
    CPU_FOREACH(dst_cpu) {
        if (dst_cpu != src_cpu) {
            TLBFlushRangeData *p = g_memdup(&d, sizeof(d));
            async_run_on_cpu(dst_cpu,
                             tlb_flush_range_by_mmuidx_async_1,
                             RUN_ON_CPU_HOST_PTR(p));
        }
    }

    tlb_flush_range_by_mmuidx_async_0(src_cpu, d);
}

void tlb_flush_page_bits_by_mmuidx_all_cpus(CPUState *src_cpu,
                                            target_ulong addr,
                                            uint16_t idxmap, unsigned bits)
{
    tlb_flush_range_by_mmuidx_all_cpus(src_cpu, addr, TARGET_PAGE_SIZE,
                                       idxmap, bits);
}

void tlb_flush_range_by_mmuidx_all_cpus_synced(CPUState *src_cpu,
                                               target_ulong addr,
                                               target_ulong len,
                                               uint16_t idxmap,
                                               unsigned bits)
{
    TLBFlushRangeData d, *p;
    CPUState *dst_cpu;

    /*
     * If all bits are significant, and len is small,
     * this devolves to tlb_flush_page.
     */
    if (bits >= TARGET_LONG_BITS && len <= TARGET_PAGE_SIZE) {
        tlb_flush_page_by_mmuidx_all_cpus_synced(src_cpu, addr, idxmap);
        return;
    }
    /* If no page bits are significant, this devolves to tlb_flush. */
    if (bits < TARGET_PAGE_BITS) {
        tlb_flush_by_mmuidx_all_cpus_synced(src_cpu, idxmap);
        return;
    }

    /* This should already be page aligned */
    d.addr = addr & TARGET_PAGE_MASK;
    d.len = len;
    d.idxmap = idxmap;
    d.bits = bits;

    /* Allocate a separate data block for each destination cpu.  */
    CPU_FOREACH(dst_cpu) {
        if (dst_cpu != src_cpu) {
            p = g_memdup(&d, sizeof(d));
            async_run_on_cpu(dst_cpu, tlb_flush_range_by_mmuidx_async_1,
                             RUN_ON_CPU_HOST_PTR(p));
        }
    }

    p = g_memdup(&d, sizeof(d));
    async_safe_run_on_cpu(src_cpu, tlb_flush_range_by_mmuidx_async_1,
                          RUN_ON_CPU_HOST_PTR(p));
}

void tlb_flush_page_bits_by_mmuidx_all_cpus_synced(CPUState *src_cpu,
                                                   target_ulong addr,
                                                   uint16_t idxmap,
                                                   unsigned bits)
{
    tlb_flush_range_by_mmuidx_all_cpus_synced(src_cpu, addr, TARGET_PAGE_SIZE,
                                              idxmap, bits);
}

/* update the TLBs so that writes to code in the virtual page 'addr'
   can be detected */
void tlb_protect_code(ram_addr_t ram_addr)
{
    cpu_physical_memory_test_and_clear_dirty(ram_addr, TARGET_PAGE_SIZE,
                                             DIRTY_MEMORY_CODE);
}

/* update the TLB so that writes in physical page 'phys_addr' are no longer
   tested for self modifying code */
void tlb_unprotect_code(ram_addr_t ram_addr)
{
    cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_CODE);
}


/*
 * Dirty write flag handling
 *
 * When the TCG code writes to a location it looks up the address in
 * the TLB and uses that data to compute the final address. If any of
 * the lower bits of the address are set then the slow path is forced.
 * There are a number of reasons to do this but for normal RAM the
 * most usual is detecting writes to code regions which may invalidate
 * generated code.
 *
 * Other vCPUs might be reading their TLBs during guest execution, so we update
 * te->addr_write with qatomic_set. We don't need to worry about this for
 * oversized guests as MTTCG is disabled for them.
 *
 * Called with tlb_c.lock held.
 */
static void tlb_reset_dirty_range_locked(CPUTLBEntry *tlb_entry,
                                         uintptr_t start, uintptr_t length)
{
    uintptr_t addr = tlb_entry->addr_write;

    if ((addr & (TLB_INVALID_MASK | TLB_MMIO |
                 TLB_DISCARD_WRITE | TLB_NOTDIRTY)) == 0) {
        addr &= TARGET_PAGE_MASK;
        addr += tlb_entry->addend;
        if ((addr - start) < length) {
#if TCG_OVERSIZED_GUEST
            tlb_entry->addr_write |= TLB_NOTDIRTY;
#else
            qatomic_set(&tlb_entry->addr_write,
                       tlb_entry->addr_write | TLB_NOTDIRTY);
#endif
        }
    }
}

/*
 * Called with tlb_c.lock held.
 * Called only from the vCPU context, i.e. the TLB's owner thread.
 */
static inline void copy_tlb_helper_locked(CPUTLBEntry *d, const CPUTLBEntry *s)
{
    *d = *s;
}

/* This is a cross vCPU call (i.e. another vCPU resetting the flags of
 * the target vCPU).
 * We must take tlb_c.lock to avoid racing with another vCPU update. The only
 * thing actually updated is the target TLB entry ->addr_write flags.
 */
void tlb_reset_dirty(CPUState *cpu, ram_addr_t start1, ram_addr_t length)
{
    CPUArchState *env;

    int mmu_idx;

    env = cpu->env_ptr;
    qemu_spin_lock(&env_tlb(env)->c.lock);
    for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
        unsigned int i;
        unsigned int n = tlb_n_entries(&env_tlb(env)->f[mmu_idx]);

        for (i = 0; i < n; i++) {
            tlb_reset_dirty_range_locked(&env_tlb(env)->f[mmu_idx].table[i],
                                         start1, length);
        }

        for (i = 0; i < CPU_VTLB_SIZE; i++) {
            tlb_reset_dirty_range_locked(&env_tlb(env)->d[mmu_idx].vtable[i],
                                         start1, length);
        }
    }
    qemu_spin_unlock(&env_tlb(env)->c.lock);
}

/* Called with tlb_c.lock held */
static inline void tlb_set_dirty1_locked(CPUTLBEntry *tlb_entry,
                                         target_ulong vaddr)
{
    if (tlb_entry->addr_write == (vaddr | TLB_NOTDIRTY)) {
        tlb_entry->addr_write = vaddr;
    }
}

/* update the TLB corresponding to virtual page vaddr
   so that it is no longer dirty */
void tlb_set_dirty(CPUState *cpu, target_ulong vaddr)
{
    CPUArchState *env = cpu->env_ptr;
    int mmu_idx;

    assert_cpu_is_self(cpu);

    vaddr &= TARGET_PAGE_MASK;
    qemu_spin_lock(&env_tlb(env)->c.lock);
    for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
        tlb_set_dirty1_locked(tlb_entry(env, mmu_idx, vaddr), vaddr);
    }

    for (mmu_idx = 0; mmu_idx < NB_MMU_MODES; mmu_idx++) {
        int k;
        for (k = 0; k < CPU_VTLB_SIZE; k++) {
            tlb_set_dirty1_locked(&env_tlb(env)->d[mmu_idx].vtable[k], vaddr);
        }
    }
    qemu_spin_unlock(&env_tlb(env)->c.lock);
}

/* Our TLB does not support large pages, so remember the area covered by
   large pages and trigger a full TLB flush if these are invalidated.  */
static void tlb_add_large_page(CPUArchState *env, int mmu_idx,
                               target_ulong vaddr, target_ulong size)
{
    target_ulong lp_addr = env_tlb(env)->d[mmu_idx].large_page_addr;
    target_ulong lp_mask = ~(size - 1);

    if (lp_addr == (target_ulong)-1) {
        /* No previous large page.  */
        lp_addr = vaddr;
    } else {
        /* Extend the existing region to include the new page.
           This is a compromise between unnecessary flushes and
           the cost of maintaining a full variable size TLB.  */
        lp_mask &= env_tlb(env)->d[mmu_idx].large_page_mask;
        while (((lp_addr ^ vaddr) & lp_mask) != 0) {
            lp_mask <<= 1;
        }
    }
    env_tlb(env)->d[mmu_idx].large_page_addr = lp_addr & lp_mask;
    env_tlb(env)->d[mmu_idx].large_page_mask = lp_mask;
}

/* Add a new TLB entry. At most one entry for a given virtual address
 * is permitted. Only a single TARGET_PAGE_SIZE region is mapped, the
 * supplied size is only used by tlb_flush_page.
 *
 * Called from TCG-generated code, which is under an RCU read-side
 * critical section.
 */
void tlb_set_page_with_attrs(CPUState *cpu, target_ulong vaddr,
                             hwaddr paddr, MemTxAttrs attrs, int prot,
                             int mmu_idx, target_ulong size)
{
    CPUArchState *env = cpu->env_ptr;
    CPUTLB *tlb = env_tlb(env);
    CPUTLBDesc *desc = &tlb->d[mmu_idx];
    MemoryRegionSection *section;
    unsigned int index;
    target_ulong address;
    target_ulong write_address;
    uintptr_t addend;
    CPUTLBEntry *te, tn;
    hwaddr iotlb, xlat, sz, paddr_page;
    target_ulong vaddr_page;
    int asidx = cpu_asidx_from_attrs(cpu, attrs);
    int wp_flags;
    bool is_ram, is_romd;

    assert_cpu_is_self(cpu);

    if (size <= TARGET_PAGE_SIZE) {
        sz = TARGET_PAGE_SIZE;
    } else {
        tlb_add_large_page(env, mmu_idx, vaddr, size);
        sz = size;
    }
    vaddr_page = vaddr & TARGET_PAGE_MASK;
    paddr_page = paddr & TARGET_PAGE_MASK;

    section = address_space_translate_for_iotlb(cpu, asidx, paddr_page,
                                                &xlat, &sz, attrs, &prot);
    assert(sz >= TARGET_PAGE_SIZE);

    tlb_debug("vaddr=" TARGET_FMT_lx " paddr=0x" TARGET_FMT_plx
              " prot=%x idx=%d\n",
              vaddr, paddr, prot, mmu_idx);

    address = vaddr_page;
    if (size < TARGET_PAGE_SIZE) {
        /* Repeat the MMU check and TLB fill on every access.  */
        address |= TLB_INVALID_MASK;
    }
    if (attrs.byte_swap) {
        address |= TLB_BSWAP;
    }

    is_ram = memory_region_is_ram(section->mr);
    is_romd = memory_region_is_romd(section->mr);

    if (is_ram || is_romd) {
        /* RAM and ROMD both have associated host memory. */
        addend = (uintptr_t)memory_region_get_ram_ptr(section->mr) + xlat;
    } else {
        /* I/O does not; force the host address to NULL. */
        addend = 0;
    }

    write_address = address;
    if (is_ram) {
        iotlb = memory_region_get_ram_addr(section->mr) + xlat;
        /*
         * Computing is_clean is expensive; avoid all that unless
         * the page is actually writable.
         */
        if (prot & PAGE_WRITE) {
            if (section->readonly) {
                write_address |= TLB_DISCARD_WRITE;
            } else if (cpu_physical_memory_is_clean(iotlb)) {
                write_address |= TLB_NOTDIRTY;
            }
        }
    } else {
        /* I/O or ROMD */
        iotlb = memory_region_section_get_iotlb(cpu, section) + xlat;
        /*
         * Writes to romd devices must go through MMIO to enable write.
         * Reads to romd devices go through the ram_ptr found above,
         * but of course reads to I/O must go through MMIO.
         */
        write_address |= TLB_MMIO;
        if (!is_romd) {
            address = write_address;
        }
    }

    wp_flags = cpu_watchpoint_address_matches(cpu, vaddr_page,
                                              TARGET_PAGE_SIZE);

    index = tlb_index(env, mmu_idx, vaddr_page);
    te = tlb_entry(env, mmu_idx, vaddr_page);

    /*
     * Hold the TLB lock for the rest of the function. We could acquire/release
     * the lock several times in the function, but it is faster to amortize the
     * acquisition cost by acquiring it just once. Note that this leads to
     * a longer critical section, but this is not a concern since the TLB lock
     * is unlikely to be contended.
     */
    qemu_spin_lock(&tlb->c.lock);

    /* Note that the tlb is no longer clean.  */
    tlb->c.dirty |= 1 << mmu_idx;

    /* Make sure there's no cached translation for the new page.  */
    tlb_flush_vtlb_page_locked(env, mmu_idx, vaddr_page);

    /*
     * Only evict the old entry to the victim tlb if it's for a
     * different page; otherwise just overwrite the stale data.
     */
    if (!tlb_hit_page_anyprot(te, vaddr_page) && !tlb_entry_is_empty(te)) {
        unsigned vidx = desc->vindex++ % CPU_VTLB_SIZE;
        CPUTLBEntry *tv = &desc->vtable[vidx];

        /* Evict the old entry into the victim tlb.  */
        copy_tlb_helper_locked(tv, te);
        desc->vfulltlb[vidx] = desc->fulltlb[index];
        tlb_n_used_entries_dec(env, mmu_idx);
    }

    /* refill the tlb */
    /*
     * At this point iotlb contains a physical section number in the lower
     * TARGET_PAGE_BITS, and either
     *  + the ram_addr_t of the page base of the target RAM (RAM)
     *  + the offset within section->mr of the page base (I/O, ROMD)
     * We subtract the vaddr_page (which is page aligned and thus won't
     * disturb the low bits) to give an offset which can be added to the
     * (non-page-aligned) vaddr of the eventual memory access to get
     * the MemoryRegion offset for the access. Note that the vaddr we
     * subtract here is that of the page base, and not the same as the
     * vaddr we add back in io_readx()/io_writex()/get_page_addr_code().
     */
    desc->fulltlb[index].xlat_section = iotlb - vaddr_page;
    desc->fulltlb[index].attrs = attrs;

    /* Now calculate the new entry */
    tn.addend = addend - vaddr_page;
    if (prot & PAGE_READ) {
        tn.addr_read = address;
        if (wp_flags & BP_MEM_READ) {
            tn.addr_read |= TLB_WATCHPOINT;
        }
    } else {
        tn.addr_read = -1;
    }

    if (prot & PAGE_EXEC) {
        tn.addr_code = address;
    } else {
        tn.addr_code = -1;
    }

    tn.addr_write = -1;
    if (prot & PAGE_WRITE) {
        tn.addr_write = write_address;
        if (prot & PAGE_WRITE_INV) {
            tn.addr_write |= TLB_INVALID_MASK;
        }
        if (wp_flags & BP_MEM_WRITE) {
            tn.addr_write |= TLB_WATCHPOINT;
        }
    }

    copy_tlb_helper_locked(te, &tn);
    tlb_n_used_entries_inc(env, mmu_idx);
    qemu_spin_unlock(&tlb->c.lock);
}

/* Add a new TLB entry, but without specifying the memory
 * transaction attributes to be used.
 */
void tlb_set_page(CPUState *cpu, target_ulong vaddr,
                  hwaddr paddr, int prot,
                  int mmu_idx, target_ulong size)
{
    tlb_set_page_with_attrs(cpu, vaddr, paddr, MEMTXATTRS_UNSPECIFIED,
                            prot, mmu_idx, size);
}

/*
 * Note: tlb_fill() can trigger a resize of the TLB. This means that all of the
 * caller's prior references to the TLB table (e.g. CPUTLBEntry pointers) must
 * be discarded and looked up again (e.g. via tlb_entry()).
 */
static void tlb_fill(CPUState *cpu, target_ulong addr, int size,
                     MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
{
    bool ok;

    /*
     * This is not a probe, so only valid return is success; failure
     * should result in exception + longjmp to the cpu loop.
     */
    ok = cpu->cc->tcg_ops->tlb_fill(cpu, addr, size,
                                    access_type, mmu_idx, false, retaddr);
    assert(ok);
}

static inline void cpu_unaligned_access(CPUState *cpu, vaddr addr,
                                        MMUAccessType access_type,
                                        int mmu_idx, uintptr_t retaddr)
{
    cpu->cc->tcg_ops->do_unaligned_access(cpu, addr, access_type,
                                          mmu_idx, retaddr);
}

static inline void cpu_transaction_failed(CPUState *cpu, hwaddr physaddr,
                                          vaddr addr, unsigned size,
                                          MMUAccessType access_type,
                                          int mmu_idx, MemTxAttrs attrs,
                                          MemTxResult response,
                                          uintptr_t retaddr)
{
    CPUClass *cc = CPU_GET_CLASS(cpu);

    if (!cpu->ignore_memory_transaction_failures &&
        cc->tcg_ops->do_transaction_failed) {
        cc->tcg_ops->do_transaction_failed(cpu, physaddr, addr, size,
                                           access_type, mmu_idx, attrs,
                                           response, retaddr);
    }
}

static uint64_t io_readx(CPUArchState *env, CPUTLBEntryFull *full,
                         int mmu_idx, target_ulong addr, uintptr_t retaddr,
                         MMUAccessType access_type, MemOp op)
{
    CPUState *cpu = env_cpu(env);
    hwaddr mr_offset;
    MemoryRegionSection *section;
    MemoryRegion *mr;
    uint64_t val;
    bool locked = false;
    MemTxResult r;

    section = iotlb_to_section(cpu, full->xlat_section, full->attrs);
    mr = section->mr;
    mr_offset = (full->xlat_section & TARGET_PAGE_MASK) + addr;
    cpu->mem_io_pc = retaddr;
    if (!cpu->can_do_io) {
        cpu_io_recompile(cpu, retaddr);
    }

    if (!qemu_mutex_iothread_locked()) {
        qemu_mutex_lock_iothread();
        locked = true;
    }
    r = memory_region_dispatch_read(mr, mr_offset, &val, op, full->attrs);
    if (r != MEMTX_OK) {
        hwaddr physaddr = mr_offset +
            section->offset_within_address_space -
            section->offset_within_region;

        cpu_transaction_failed(cpu, physaddr, addr, memop_size(op), access_type,
                               mmu_idx, full->attrs, r, retaddr);
    }
    if (locked) {
        qemu_mutex_unlock_iothread();
    }

    return val;
}

/*
 * Save a potentially trashed CPUTLBEntryFull for later lookup by plugin.
 * This is read by tlb_plugin_lookup if the fulltlb entry doesn't match
 * because of the side effect of io_writex changing memory layout.
 */
static void save_iotlb_data(CPUState *cs, MemoryRegionSection *section,
                            hwaddr mr_offset)
{
#ifdef CONFIG_PLUGIN
    SavedIOTLB *saved = &cs->saved_iotlb;
    saved->section = section;
    saved->mr_offset = mr_offset;
#endif
}

static void io_writex(CPUArchState *env, CPUTLBEntryFull *full,
                      int mmu_idx, uint64_t val, target_ulong addr,
                      uintptr_t retaddr, MemOp op)
{
    CPUState *cpu = env_cpu(env);
    hwaddr mr_offset;
    MemoryRegionSection *section;
    MemoryRegion *mr;
    bool locked = false;
    MemTxResult r;

    section = iotlb_to_section(cpu, full->xlat_section, full->attrs);
    mr = section->mr;
    mr_offset = (full->xlat_section & TARGET_PAGE_MASK) + addr;
    if (!cpu->can_do_io) {
        cpu_io_recompile(cpu, retaddr);
    }
    cpu->mem_io_pc = retaddr;

    /*
     * The memory_region_dispatch may trigger a flush/resize
     * so for plugins we save the iotlb_data just in case.
     */
    save_iotlb_data(cpu, section, mr_offset);

    if (!qemu_mutex_iothread_locked()) {
        qemu_mutex_lock_iothread();
        locked = true;
    }
    r = memory_region_dispatch_write(mr, mr_offset, val, op, full->attrs);
    if (r != MEMTX_OK) {
        hwaddr physaddr = mr_offset +
            section->offset_within_address_space -
            section->offset_within_region;

        cpu_transaction_failed(cpu, physaddr, addr, memop_size(op),
                               MMU_DATA_STORE, mmu_idx, full->attrs, r,
                               retaddr);
    }
    if (locked) {
        qemu_mutex_unlock_iothread();
    }
}

static inline target_ulong tlb_read_ofs(CPUTLBEntry *entry, size_t ofs)
{
#if TCG_OVERSIZED_GUEST
    return *(target_ulong *)((uintptr_t)entry + ofs);
#else
    /* ofs might correspond to .addr_write, so use qatomic_read */
    return qatomic_read((target_ulong *)((uintptr_t)entry + ofs));
#endif
}

/* Return true if ADDR is present in the victim tlb, and has been copied
   back to the main tlb.  */
static bool victim_tlb_hit(CPUArchState *env, size_t mmu_idx, size_t index,
                           size_t elt_ofs, target_ulong page)
{
    size_t vidx;

    assert_cpu_is_self(env_cpu(env));
    for (vidx = 0; vidx < CPU_VTLB_SIZE; ++vidx) {
        CPUTLBEntry *vtlb = &env_tlb(env)->d[mmu_idx].vtable[vidx];
        target_ulong cmp;

        /* elt_ofs might correspond to .addr_write, so use qatomic_read */
#if TCG_OVERSIZED_GUEST
        cmp = *(target_ulong *)((uintptr_t)vtlb + elt_ofs);
#else
        cmp = qatomic_read((target_ulong *)((uintptr_t)vtlb + elt_ofs));
#endif

        if (cmp == page) {
            /* Found entry in victim tlb, swap tlb and iotlb.  */
            CPUTLBEntry tmptlb, *tlb = &env_tlb(env)->f[mmu_idx].table[index];

            qemu_spin_lock(&env_tlb(env)->c.lock);
            copy_tlb_helper_locked(&tmptlb, tlb);
            copy_tlb_helper_locked(tlb, vtlb);
            copy_tlb_helper_locked(vtlb, &tmptlb);
            qemu_spin_unlock(&env_tlb(env)->c.lock);

            CPUTLBEntryFull *f1 = &env_tlb(env)->d[mmu_idx].fulltlb[index];
            CPUTLBEntryFull *f2 = &env_tlb(env)->d[mmu_idx].vfulltlb[vidx];
            CPUTLBEntryFull tmpf;
            tmpf = *f1; *f1 = *f2; *f2 = tmpf;
            return true;
        }
    }
    return false;
}

/* Macro to call the above, with local variables from the use context.  */
#define VICTIM_TLB_HIT(TY, ADDR) \
  victim_tlb_hit(env, mmu_idx, index, offsetof(CPUTLBEntry, TY), \
                 (ADDR) & TARGET_PAGE_MASK)

static void notdirty_write(CPUState *cpu, vaddr mem_vaddr, unsigned size,
                           CPUTLBEntryFull *full, uintptr_t retaddr)
{
    ram_addr_t ram_addr = mem_vaddr + full->xlat_section;

    trace_memory_notdirty_write_access(mem_vaddr, ram_addr, size);

    if (!cpu_physical_memory_get_dirty_flag(ram_addr, DIRTY_MEMORY_CODE)) {
        struct page_collection *pages
            = page_collection_lock(ram_addr, ram_addr + size);
        tb_invalidate_phys_page_fast(pages, ram_addr, size, retaddr);
        page_collection_unlock(pages);
    }

    /*
     * Set both VGA and migration bits for simplicity and to remove
     * the notdirty callback faster.
     */
    cpu_physical_memory_set_dirty_range(ram_addr, size, DIRTY_CLIENTS_NOCODE);

    /* We remove the notdirty callback only if the code has been flushed. */
    if (!cpu_physical_memory_is_clean(ram_addr)) {
        trace_memory_notdirty_set_dirty(mem_vaddr);
        tlb_set_dirty(cpu, mem_vaddr);
    }
}

static int probe_access_internal(CPUArchState *env, target_ulong addr,
                                 int fault_size, MMUAccessType access_type,
                                 int mmu_idx, bool nonfault,
                                 void **phost, uintptr_t retaddr)
{
    uintptr_t index = tlb_index(env, mmu_idx, addr);
    CPUTLBEntry *entry = tlb_entry(env, mmu_idx, addr);
    target_ulong tlb_addr, page_addr;
    size_t elt_ofs;
    int flags;

    switch (access_type) {
    case MMU_DATA_LOAD:
        elt_ofs = offsetof(CPUTLBEntry, addr_read);
        break;
    case MMU_DATA_STORE:
        elt_ofs = offsetof(CPUTLBEntry, addr_write);
        break;
    case MMU_INST_FETCH:
        elt_ofs = offsetof(CPUTLBEntry, addr_code);
        break;
    default:
        g_assert_not_reached();
    }
    tlb_addr = tlb_read_ofs(entry, elt_ofs);

    page_addr = addr & TARGET_PAGE_MASK;
    if (!tlb_hit_page(tlb_addr, page_addr)) {
        if (!victim_tlb_hit(env, mmu_idx, index, elt_ofs, page_addr)) {
            CPUState *cs = env_cpu(env);

            if (!cs->cc->tcg_ops->tlb_fill(cs, addr, fault_size, access_type,
                                           mmu_idx, nonfault, retaddr)) {
                /* Non-faulting page table read failed.  */
                *phost = NULL;
                return TLB_INVALID_MASK;
            }

            /* TLB resize via tlb_fill may have moved the entry.  */
            entry = tlb_entry(env, mmu_idx, addr);
        }
        tlb_addr = tlb_read_ofs(entry, elt_ofs);
    }
    flags = tlb_addr & TLB_FLAGS_MASK;

    /* Fold all "mmio-like" bits into TLB_MMIO.  This is not RAM.  */
    if (unlikely(flags & ~(TLB_WATCHPOINT | TLB_NOTDIRTY))) {
        *phost = NULL;
        return TLB_MMIO;
    }

    /* Everything else is RAM. */
    *phost = (void *)((uintptr_t)addr + entry->addend);
    return flags;
}

int probe_access_flags(CPUArchState *env, target_ulong addr,
                       MMUAccessType access_type, int mmu_idx,
                       bool nonfault, void **phost, uintptr_t retaddr)
{
    int flags;

    flags = probe_access_internal(env, addr, 0, access_type, mmu_idx,
                                  nonfault, phost, retaddr);

    /* Handle clean RAM pages.  */
    if (unlikely(flags & TLB_NOTDIRTY)) {
        uintptr_t index = tlb_index(env, mmu_idx, addr);
        CPUTLBEntryFull *full = &env_tlb(env)->d[mmu_idx].fulltlb[index];

        notdirty_write(env_cpu(env), addr, 1, full, retaddr);
        flags &= ~TLB_NOTDIRTY;
    }

    return flags;
}

void *probe_access(CPUArchState *env, target_ulong addr, int size,
                   MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
{
    void *host;
    int flags;

    g_assert(-(addr | TARGET_PAGE_MASK) >= size);

    flags = probe_access_internal(env, addr, size, access_type, mmu_idx,
                                  false, &host, retaddr);

    /* Per the interface, size == 0 merely faults the access. */
    if (size == 0) {
        return NULL;
    }

    if (unlikely(flags & (TLB_NOTDIRTY | TLB_WATCHPOINT))) {
        uintptr_t index = tlb_index(env, mmu_idx, addr);
        CPUTLBEntryFull *full = &env_tlb(env)->d[mmu_idx].fulltlb[index];

        /* Handle watchpoints.  */
        if (flags & TLB_WATCHPOINT) {
            int wp_access = (access_type == MMU_DATA_STORE
                             ? BP_MEM_WRITE : BP_MEM_READ);
            cpu_check_watchpoint(env_cpu(env), addr, size,
                                 full->attrs, wp_access, retaddr);
        }

        /* Handle clean RAM pages.  */
        if (flags & TLB_NOTDIRTY) {
            notdirty_write(env_cpu(env), addr, 1, full, retaddr);
        }
    }

    return host;
}

void *tlb_vaddr_to_host(CPUArchState *env, abi_ptr addr,
                        MMUAccessType access_type, int mmu_idx)
{
    void *host;
    int flags;

    flags = probe_access_internal(env, addr, 0, access_type,
                                  mmu_idx, true, &host, 0);

    /* No combination of flags are expected by the caller. */
    return flags ? NULL : host;
}

/*
 * Return a ram_addr_t for the virtual address for execution.
 *
 * Return -1 if we can't translate and execute from an entire page
 * of RAM.  This will force us to execute by loading and translating
 * one insn at a time, without caching.
 *
 * NOTE: This function will trigger an exception if the page is
 * not executable.
 */
tb_page_addr_t get_page_addr_code_hostp(CPUArchState *env, target_ulong addr,
                                        void **hostp)
{
    void *p;

    (void)probe_access_internal(env, addr, 1, MMU_INST_FETCH,
                                cpu_mmu_index(env, true), false, &p, 0);
    if (p == NULL) {
        return -1;
    }
    if (hostp) {
        *hostp = p;
    }
    return qemu_ram_addr_from_host_nofail(p);
}

#ifdef CONFIG_PLUGIN
/*
 * Perform a TLB lookup and populate the qemu_plugin_hwaddr structure.
 * This should be a hot path as we will have just looked this path up
 * in the softmmu lookup code (or helper). We don't handle re-fills or
 * checking the victim table. This is purely informational.
 *
 * This almost never fails as the memory access being instrumented
 * should have just filled the TLB. The one corner case is io_writex
 * which can cause TLB flushes and potential resizing of the TLBs
 * losing the information we need. In those cases we need to recover
 * data from a copy of the CPUTLBEntryFull. As long as this always occurs
 * from the same thread (which a mem callback will be) this is safe.
 */

bool tlb_plugin_lookup(CPUState *cpu, target_ulong addr, int mmu_idx,
                       bool is_store, struct qemu_plugin_hwaddr *data)
{
    CPUArchState *env = cpu->env_ptr;
    CPUTLBEntry *tlbe = tlb_entry(env, mmu_idx, addr);
    uintptr_t index = tlb_index(env, mmu_idx, addr);
    target_ulong tlb_addr = is_store ? tlb_addr_write(tlbe) : tlbe->addr_read;

    if (likely(tlb_hit(tlb_addr, addr))) {
        /* We must have an iotlb entry for MMIO */
        if (tlb_addr & TLB_MMIO) {
            CPUTLBEntryFull *full;
            full = &env_tlb(env)->d[mmu_idx].fulltlb[index];
            data->is_io = true;
            data->v.io.section =
                iotlb_to_section(cpu, full->xlat_section, full->attrs);
            data->v.io.offset = (full->xlat_section & TARGET_PAGE_MASK) + addr;
        } else {
            data->is_io = false;
            data->v.ram.hostaddr = (void *)((uintptr_t)addr + tlbe->addend);
        }
        return true;
    } else {
        SavedIOTLB *saved = &cpu->saved_iotlb;
        data->is_io = true;
        data->v.io.section = saved->section;
        data->v.io.offset = saved->mr_offset;
        return true;
    }
}

#endif

/*
 * Probe for an atomic operation.  Do not allow unaligned operations,
 * or io operations to proceed.  Return the host address.
 *
 * @prot may be PAGE_READ, PAGE_WRITE, or PAGE_READ|PAGE_WRITE.
 */
static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
                               MemOpIdx oi, int size, int prot,
                               uintptr_t retaddr)
{
    uintptr_t mmu_idx = get_mmuidx(oi);
    MemOp mop = get_memop(oi);
    int a_bits = get_alignment_bits(mop);
    uintptr_t index;
    CPUTLBEntry *tlbe;
    target_ulong tlb_addr;
    void *hostaddr;

    tcg_debug_assert(mmu_idx < NB_MMU_MODES);

    /* Adjust the given return address.  */
    retaddr -= GETPC_ADJ;

    /* Enforce guest required alignment.  */
    if (unlikely(a_bits > 0 && (addr & ((1 << a_bits) - 1)))) {
        /* ??? Maybe indicate atomic op to cpu_unaligned_access */
        cpu_unaligned_access(env_cpu(env), addr, MMU_DATA_STORE,
                             mmu_idx, retaddr);
    }

    /* Enforce qemu required alignment.  */
    if (unlikely(addr & (size - 1))) {
        /* We get here if guest alignment was not requested,
           or was not enforced by cpu_unaligned_access above.
           We might widen the access and emulate, but for now
           mark an exception and exit the cpu loop.  */
        goto stop_the_world;
    }

    index = tlb_index(env, mmu_idx, addr);
    tlbe = tlb_entry(env, mmu_idx, addr);

    /* Check TLB entry and enforce page permissions.  */
    if (prot & PAGE_WRITE) {
        tlb_addr = tlb_addr_write(tlbe);
        if (!tlb_hit(tlb_addr, addr)) {
            if (!VICTIM_TLB_HIT(addr_write, addr)) {
                tlb_fill(env_cpu(env), addr, size,
                         MMU_DATA_STORE, mmu_idx, retaddr);
                index = tlb_index(env, mmu_idx, addr);
                tlbe = tlb_entry(env, mmu_idx, addr);
            }
            tlb_addr = tlb_addr_write(tlbe) & ~TLB_INVALID_MASK;
        }

        /* Let the guest notice RMW on a write-only page.  */
        if ((prot & PAGE_READ) &&
            unlikely(tlbe->addr_read != (tlb_addr & ~TLB_NOTDIRTY))) {
            tlb_fill(env_cpu(env), addr, size,
                     MMU_DATA_LOAD, mmu_idx, retaddr);
            /*
             * Since we don't support reads and writes to different addresses,
             * and we do have the proper page loaded for write, this shouldn't
             * ever return.  But just in case, handle via stop-the-world.
             */
            goto stop_the_world;
        }
    } else /* if (prot & PAGE_READ) */ {
        tlb_addr = tlbe->addr_read;
        if (!tlb_hit(tlb_addr, addr)) {
            if (!VICTIM_TLB_HIT(addr_write, addr)) {
                tlb_fill(env_cpu(env), addr, size,
                         MMU_DATA_LOAD, mmu_idx, retaddr);
                index = tlb_index(env, mmu_idx, addr);
                tlbe = tlb_entry(env, mmu_idx, addr);
            }
            tlb_addr = tlbe->addr_read & ~TLB_INVALID_MASK;
        }
    }

    /* Notice an IO access or a needs-MMU-lookup access */
    if (unlikely(tlb_addr & TLB_MMIO)) {
        /* There's really nothing that can be done to
           support this apart from stop-the-world.  */
        goto stop_the_world;
    }

    hostaddr = (void *)((uintptr_t)addr + tlbe->addend);

    if (unlikely(tlb_addr & TLB_NOTDIRTY)) {
        notdirty_write(env_cpu(env), addr, size,
                       &env_tlb(env)->d[mmu_idx].fulltlb[index], retaddr);
    }

    return hostaddr;

 stop_the_world:
    cpu_loop_exit_atomic(env_cpu(env), retaddr);
}

/*
 * Verify that we have passed the correct MemOp to the correct function.
 *
 * In the case of the helper_*_mmu functions, we will have done this by
 * using the MemOp to look up the helper during code generation.
 *
 * In the case of the cpu_*_mmu functions, this is up to the caller.
 * We could present one function to target code, and dispatch based on
 * the MemOp, but so far we have worked hard to avoid an indirect function
 * call along the memory path.
 */
static void validate_memop(MemOpIdx oi, MemOp expected)
{
#ifdef CONFIG_DEBUG_TCG
    MemOp have = get_memop(oi) & (MO_SIZE | MO_BSWAP);
    assert(have == expected);
#endif
}

/*
 * Load Helpers
 *
 * We support two different access types. SOFTMMU_CODE_ACCESS is
 * specifically for reading instructions from system memory. It is
 * called by the translation loop and in some helpers where the code
 * is disassembled. It shouldn't be called directly by guest code.
 */

typedef uint64_t FullLoadHelper(CPUArchState *env, target_ulong addr,
                                MemOpIdx oi, uintptr_t retaddr);

static inline uint64_t QEMU_ALWAYS_INLINE
load_memop(const void *haddr, MemOp op)
{
    switch (op) {
    case MO_UB:
        return ldub_p(haddr);
    case MO_BEUW:
        return lduw_be_p(haddr);
    case MO_LEUW:
        return lduw_le_p(haddr);
    case MO_BEUL:
        return (uint32_t)ldl_be_p(haddr);
    case MO_LEUL:
        return (uint32_t)ldl_le_p(haddr);
    case MO_BEUQ:
        return ldq_be_p(haddr);
    case MO_LEUQ:
        return ldq_le_p(haddr);
    default:
        qemu_build_not_reached();
    }
}

static inline uint64_t QEMU_ALWAYS_INLINE
load_helper(CPUArchState *env, target_ulong addr, MemOpIdx oi,
            uintptr_t retaddr, MemOp op, bool code_read,
            FullLoadHelper *full_load)
{
    const size_t tlb_off = code_read ?
        offsetof(CPUTLBEntry, addr_code) : offsetof(CPUTLBEntry, addr_read);
    const MMUAccessType access_type =
        code_read ? MMU_INST_FETCH : MMU_DATA_LOAD;
    const unsigned a_bits = get_alignment_bits(get_memop(oi));
    const size_t size = memop_size(op);
    uintptr_t mmu_idx = get_mmuidx(oi);
    uintptr_t index;
    CPUTLBEntry *entry;
    target_ulong tlb_addr;
    void *haddr;
    uint64_t res;

    tcg_debug_assert(mmu_idx < NB_MMU_MODES);

    /* Handle CPU specific unaligned behaviour */
    if (addr & ((1 << a_bits) - 1)) {
        cpu_unaligned_access(env_cpu(env), addr, access_type,
                             mmu_idx, retaddr);
    }

    index = tlb_index(env, mmu_idx, addr);
    entry = tlb_entry(env, mmu_idx, addr);
    tlb_addr = code_read ? entry->addr_code : entry->addr_read;

    /* If the TLB entry is for a different page, reload and try again.  */
    if (!tlb_hit(tlb_addr, addr)) {
        if (!victim_tlb_hit(env, mmu_idx, index, tlb_off,
                            addr & TARGET_PAGE_MASK)) {
            tlb_fill(env_cpu(env), addr, size,
                     access_type, mmu_idx, retaddr);
            index = tlb_index(env, mmu_idx, addr);
            entry = tlb_entry(env, mmu_idx, addr);
        }
        tlb_addr = code_read ? entry->addr_code : entry->addr_read;
        tlb_addr &= ~TLB_INVALID_MASK;
    }

    /* Handle anything that isn't just a straight memory access.  */
    if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) {
        CPUTLBEntryFull *full;
        bool need_swap;

        /* For anything that is unaligned, recurse through full_load.  */
        if ((addr & (size - 1)) != 0) {
            goto do_unaligned_access;
        }

        full = &env_tlb(env)->d[mmu_idx].fulltlb[index];

        /* Handle watchpoints.  */
        if (unlikely(tlb_addr & TLB_WATCHPOINT)) {
            /* On watchpoint hit, this will longjmp out.  */
            cpu_check_watchpoint(env_cpu(env), addr, size,
                                 full->attrs, BP_MEM_READ, retaddr);
        }

        need_swap = size > 1 && (tlb_addr & TLB_BSWAP);

        /* Handle I/O access.  */
        if (likely(tlb_addr & TLB_MMIO)) {
            return io_readx(env, full, mmu_idx, addr, retaddr,
                            access_type, op ^ (need_swap * MO_BSWAP));
        }

        haddr = (void *)((uintptr_t)addr + entry->addend);

        /*
         * Keep these two load_memop separate to ensure that the compiler
         * is able to fold the entire function to a single instruction.
         * There is a build-time assert inside to remind you of this.  ;-)
         */
        if (unlikely(need_swap)) {
            return load_memop(haddr, op ^ MO_BSWAP);
        }
        return load_memop(haddr, op);
    }

    /* Handle slow unaligned access (it spans two pages or IO).  */
    if (size > 1
        && unlikely((addr & ~TARGET_PAGE_MASK) + size - 1
                    >= TARGET_PAGE_SIZE)) {
        target_ulong addr1, addr2;
        uint64_t r1, r2;
        unsigned shift;
    do_unaligned_access:
        addr1 = addr & ~((target_ulong)size - 1);
        addr2 = addr1 + size;
        r1 = full_load(env, addr1, oi, retaddr);
        r2 = full_load(env, addr2, oi, retaddr);
        shift = (addr & (size - 1)) * 8;

        if (memop_big_endian(op)) {
            /* Big-endian combine.  */
            res = (r1 << shift) | (r2 >> ((size * 8) - shift));
        } else {
            /* Little-endian combine.  */
            res = (r1 >> shift) | (r2 << ((size * 8) - shift));
        }
        return res & MAKE_64BIT_MASK(0, size * 8);
    }

    haddr = (void *)((uintptr_t)addr + entry->addend);
    return load_memop(haddr, op);
}

/*
 * For the benefit of TCG generated code, we want to avoid the
 * complication of ABI-specific return type promotion and always
 * return a value extended to the register size of the host. This is
 * tcg_target_long, except in the case of a 32-bit host and 64-bit
 * data, and for that we always have uint64_t.
 *
 * We don't bother with this widened value for SOFTMMU_CODE_ACCESS.
 */

static uint64_t full_ldub_mmu(CPUArchState *env, target_ulong addr,
                              MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_UB);
    return load_helper(env, addr, oi, retaddr, MO_UB, false, full_ldub_mmu);
}

tcg_target_ulong helper_ret_ldub_mmu(CPUArchState *env, target_ulong addr,
                                     MemOpIdx oi, uintptr_t retaddr)
{
    return full_ldub_mmu(env, addr, oi, retaddr);
}

static uint64_t full_le_lduw_mmu(CPUArchState *env, target_ulong addr,
                                 MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_LEUW);
    return load_helper(env, addr, oi, retaddr, MO_LEUW, false,
                       full_le_lduw_mmu);
}

tcg_target_ulong helper_le_lduw_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return full_le_lduw_mmu(env, addr, oi, retaddr);
}

static uint64_t full_be_lduw_mmu(CPUArchState *env, target_ulong addr,
                                 MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_BEUW);
    return load_helper(env, addr, oi, retaddr, MO_BEUW, false,
                       full_be_lduw_mmu);
}

tcg_target_ulong helper_be_lduw_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return full_be_lduw_mmu(env, addr, oi, retaddr);
}

static uint64_t full_le_ldul_mmu(CPUArchState *env, target_ulong addr,
                                 MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_LEUL);
    return load_helper(env, addr, oi, retaddr, MO_LEUL, false,
                       full_le_ldul_mmu);
}

tcg_target_ulong helper_le_ldul_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return full_le_ldul_mmu(env, addr, oi, retaddr);
}

static uint64_t full_be_ldul_mmu(CPUArchState *env, target_ulong addr,
                                 MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_BEUL);
    return load_helper(env, addr, oi, retaddr, MO_BEUL, false,
                       full_be_ldul_mmu);
}

tcg_target_ulong helper_be_ldul_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return full_be_ldul_mmu(env, addr, oi, retaddr);
}

uint64_t helper_le_ldq_mmu(CPUArchState *env, target_ulong addr,
                           MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_LEUQ);
    return load_helper(env, addr, oi, retaddr, MO_LEUQ, false,
                       helper_le_ldq_mmu);
}

uint64_t helper_be_ldq_mmu(CPUArchState *env, target_ulong addr,
                           MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_BEUQ);
    return load_helper(env, addr, oi, retaddr, MO_BEUQ, false,
                       helper_be_ldq_mmu);
}

/*
 * Provide signed versions of the load routines as well.  We can of course
 * avoid this for 64-bit data, or for 32-bit data on 32-bit host.
 */


tcg_target_ulong helper_ret_ldsb_mmu(CPUArchState *env, target_ulong addr,
                                     MemOpIdx oi, uintptr_t retaddr)
{
    return (int8_t)helper_ret_ldub_mmu(env, addr, oi, retaddr);
}

tcg_target_ulong helper_le_ldsw_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return (int16_t)helper_le_lduw_mmu(env, addr, oi, retaddr);
}

tcg_target_ulong helper_be_ldsw_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return (int16_t)helper_be_lduw_mmu(env, addr, oi, retaddr);
}

tcg_target_ulong helper_le_ldsl_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return (int32_t)helper_le_ldul_mmu(env, addr, oi, retaddr);
}

tcg_target_ulong helper_be_ldsl_mmu(CPUArchState *env, target_ulong addr,
                                    MemOpIdx oi, uintptr_t retaddr)
{
    return (int32_t)helper_be_ldul_mmu(env, addr, oi, retaddr);
}

/*
 * Load helpers for cpu_ldst.h.
 */

static inline uint64_t cpu_load_helper(CPUArchState *env, abi_ptr addr,
                                       MemOpIdx oi, uintptr_t retaddr,
                                       FullLoadHelper *full_load)
{
    uint64_t ret;

    ret = full_load(env, addr, oi, retaddr);
    qemu_plugin_vcpu_mem_cb(env_cpu(env), addr, oi, QEMU_PLUGIN_MEM_R);
    return ret;
}

uint8_t cpu_ldb_mmu(CPUArchState *env, abi_ptr addr, MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, full_ldub_mmu);
}

uint16_t cpu_ldw_be_mmu(CPUArchState *env, abi_ptr addr,
                        MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, full_be_lduw_mmu);
}

uint32_t cpu_ldl_be_mmu(CPUArchState *env, abi_ptr addr,
                        MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, full_be_ldul_mmu);
}

uint64_t cpu_ldq_be_mmu(CPUArchState *env, abi_ptr addr,
                        MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, helper_be_ldq_mmu);
}

uint16_t cpu_ldw_le_mmu(CPUArchState *env, abi_ptr addr,
                        MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, full_le_lduw_mmu);
}

uint32_t cpu_ldl_le_mmu(CPUArchState *env, abi_ptr addr,
                        MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, full_le_ldul_mmu);
}

uint64_t cpu_ldq_le_mmu(CPUArchState *env, abi_ptr addr,
                        MemOpIdx oi, uintptr_t ra)
{
    return cpu_load_helper(env, addr, oi, ra, helper_le_ldq_mmu);
}

/*
 * Store Helpers
 */

static inline void QEMU_ALWAYS_INLINE
store_memop(void *haddr, uint64_t val, MemOp op)
{
    switch (op) {
    case MO_UB:
        stb_p(haddr, val);
        break;
    case MO_BEUW:
        stw_be_p(haddr, val);
        break;
    case MO_LEUW:
        stw_le_p(haddr, val);
        break;
    case MO_BEUL:
        stl_be_p(haddr, val);
        break;
    case MO_LEUL:
        stl_le_p(haddr, val);
        break;
    case MO_BEUQ:
        stq_be_p(haddr, val);
        break;
    case MO_LEUQ:
        stq_le_p(haddr, val);
        break;
    default:
        qemu_build_not_reached();
    }
}

static void full_stb_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                         MemOpIdx oi, uintptr_t retaddr);

static void __attribute__((noinline))
store_helper_unaligned(CPUArchState *env, target_ulong addr, uint64_t val,
                       uintptr_t retaddr, size_t size, uintptr_t mmu_idx,
                       bool big_endian)
{
    const size_t tlb_off = offsetof(CPUTLBEntry, addr_write);
    uintptr_t index, index2;
    CPUTLBEntry *entry, *entry2;
    target_ulong page1, page2, tlb_addr, tlb_addr2;
    MemOpIdx oi;
    size_t size2;
    int i;

    /*
     * Ensure the second page is in the TLB.  Note that the first page
     * is already guaranteed to be filled, and that the second page
     * cannot evict the first.  An exception to this rule is PAGE_WRITE_INV
     * handling: the first page could have evicted itself.
     */
    page1 = addr & TARGET_PAGE_MASK;
    page2 = (addr + size) & TARGET_PAGE_MASK;
    size2 = (addr + size) & ~TARGET_PAGE_MASK;
    index2 = tlb_index(env, mmu_idx, page2);
    entry2 = tlb_entry(env, mmu_idx, page2);

    tlb_addr2 = tlb_addr_write(entry2);
    if (page1 != page2 && !tlb_hit_page(tlb_addr2, page2)) {
        if (!victim_tlb_hit(env, mmu_idx, index2, tlb_off, page2)) {
            tlb_fill(env_cpu(env), page2, size2, MMU_DATA_STORE,
                     mmu_idx, retaddr);
            index2 = tlb_index(env, mmu_idx, page2);
            entry2 = tlb_entry(env, mmu_idx, page2);
        }
        tlb_addr2 = tlb_addr_write(entry2);
    }

    index = tlb_index(env, mmu_idx, addr);
    entry = tlb_entry(env, mmu_idx, addr);
    tlb_addr = tlb_addr_write(entry);

    /*
     * Handle watchpoints.  Since this may trap, all checks
     * must happen before any store.
     */
    if (unlikely(tlb_addr & TLB_WATCHPOINT)) {
        cpu_check_watchpoint(env_cpu(env), addr, size - size2,
                             env_tlb(env)->d[mmu_idx].fulltlb[index].attrs,
                             BP_MEM_WRITE, retaddr);
    }
    if (unlikely(tlb_addr2 & TLB_WATCHPOINT)) {
        cpu_check_watchpoint(env_cpu(env), page2, size2,
                             env_tlb(env)->d[mmu_idx].fulltlb[index2].attrs,
                             BP_MEM_WRITE, retaddr);
    }

    /*
     * XXX: not efficient, but simple.
     * This loop must go in the forward direction to avoid issues
     * with self-modifying code in Windows 64-bit.
     */
    oi = make_memop_idx(MO_UB, mmu_idx);
    if (big_endian) {
        for (i = 0; i < size; ++i) {
            /* Big-endian extract.  */
            uint8_t val8 = val >> (((size - 1) * 8) - (i * 8));
            full_stb_mmu(env, addr + i, val8, oi, retaddr);
        }
    } else {
        for (i = 0; i < size; ++i) {
            /* Little-endian extract.  */
            uint8_t val8 = val >> (i * 8);
            full_stb_mmu(env, addr + i, val8, oi, retaddr);
        }
    }
}

static inline void QEMU_ALWAYS_INLINE
store_helper(CPUArchState *env, target_ulong addr, uint64_t val,
             MemOpIdx oi, uintptr_t retaddr, MemOp op)
{
    const size_t tlb_off = offsetof(CPUTLBEntry, addr_write);
    const unsigned a_bits = get_alignment_bits(get_memop(oi));
    const size_t size = memop_size(op);
    uintptr_t mmu_idx = get_mmuidx(oi);
    uintptr_t index;
    CPUTLBEntry *entry;
    target_ulong tlb_addr;
    void *haddr;

    tcg_debug_assert(mmu_idx < NB_MMU_MODES);

    /* Handle CPU specific unaligned behaviour */
    if (addr & ((1 << a_bits) - 1)) {
        cpu_unaligned_access(env_cpu(env), addr, MMU_DATA_STORE,
                             mmu_idx, retaddr);
    }

    index = tlb_index(env, mmu_idx, addr);
    entry = tlb_entry(env, mmu_idx, addr);
    tlb_addr = tlb_addr_write(entry);

    /* If the TLB entry is for a different page, reload and try again.  */
    if (!tlb_hit(tlb_addr, addr)) {
        if (!victim_tlb_hit(env, mmu_idx, index, tlb_off,
            addr & TARGET_PAGE_MASK)) {
            tlb_fill(env_cpu(env), addr, size, MMU_DATA_STORE,
                     mmu_idx, retaddr);
            index = tlb_index(env, mmu_idx, addr);
            entry = tlb_entry(env, mmu_idx, addr);
        }
        tlb_addr = tlb_addr_write(entry) & ~TLB_INVALID_MASK;
    }

    /* Handle anything that isn't just a straight memory access.  */
    if (unlikely(tlb_addr & ~TARGET_PAGE_MASK)) {
        CPUTLBEntryFull *full;
        bool need_swap;

        /* For anything that is unaligned, recurse through byte stores.  */
        if ((addr & (size - 1)) != 0) {
            goto do_unaligned_access;
        }

        full = &env_tlb(env)->d[mmu_idx].fulltlb[index];

        /* Handle watchpoints.  */
        if (unlikely(tlb_addr & TLB_WATCHPOINT)) {
            /* On watchpoint hit, this will longjmp out.  */
            cpu_check_watchpoint(env_cpu(env), addr, size,
                                 full->attrs, BP_MEM_WRITE, retaddr);
        }

        need_swap = size > 1 && (tlb_addr & TLB_BSWAP);

        /* Handle I/O access.  */
        if (tlb_addr & TLB_MMIO) {
            io_writex(env, full, mmu_idx, val, addr, retaddr,
                      op ^ (need_swap * MO_BSWAP));
            return;
        }

        /* Ignore writes to ROM.  */
        if (unlikely(tlb_addr & TLB_DISCARD_WRITE)) {
            return;
        }

        /* Handle clean RAM pages.  */
        if (tlb_addr & TLB_NOTDIRTY) {
            notdirty_write(env_cpu(env), addr, size, full, retaddr);
        }

        haddr = (void *)((uintptr_t)addr + entry->addend);

        /*
         * Keep these two store_memop separate to ensure that the compiler
         * is able to fold the entire function to a single instruction.
         * There is a build-time assert inside to remind you of this.  ;-)
         */
        if (unlikely(need_swap)) {
            store_memop(haddr, val, op ^ MO_BSWAP);
        } else {
            store_memop(haddr, val, op);
        }
        return;
    }

    /* Handle slow unaligned access (it spans two pages or IO).  */
    if (size > 1
        && unlikely((addr & ~TARGET_PAGE_MASK) + size - 1
                     >= TARGET_PAGE_SIZE)) {
    do_unaligned_access:
        store_helper_unaligned(env, addr, val, retaddr, size,
                               mmu_idx, memop_big_endian(op));
        return;
    }

    haddr = (void *)((uintptr_t)addr + entry->addend);
    store_memop(haddr, val, op);
}

static void __attribute__((noinline))
full_stb_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
             MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_UB);
    store_helper(env, addr, val, oi, retaddr, MO_UB);
}

void helper_ret_stb_mmu(CPUArchState *env, target_ulong addr, uint8_t val,
                        MemOpIdx oi, uintptr_t retaddr)
{
    full_stb_mmu(env, addr, val, oi, retaddr);
}

static void full_le_stw_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                            MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_LEUW);
    store_helper(env, addr, val, oi, retaddr, MO_LEUW);
}

void helper_le_stw_mmu(CPUArchState *env, target_ulong addr, uint16_t val,
                       MemOpIdx oi, uintptr_t retaddr)
{
    full_le_stw_mmu(env, addr, val, oi, retaddr);
}

static void full_be_stw_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                            MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_BEUW);
    store_helper(env, addr, val, oi, retaddr, MO_BEUW);
}

void helper_be_stw_mmu(CPUArchState *env, target_ulong addr, uint16_t val,
                       MemOpIdx oi, uintptr_t retaddr)
{
    full_be_stw_mmu(env, addr, val, oi, retaddr);
}

static void full_le_stl_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                            MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_LEUL);
    store_helper(env, addr, val, oi, retaddr, MO_LEUL);
}

void helper_le_stl_mmu(CPUArchState *env, target_ulong addr, uint32_t val,
                       MemOpIdx oi, uintptr_t retaddr)
{
    full_le_stl_mmu(env, addr, val, oi, retaddr);
}

static void full_be_stl_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                            MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_BEUL);
    store_helper(env, addr, val, oi, retaddr, MO_BEUL);
}

void helper_be_stl_mmu(CPUArchState *env, target_ulong addr, uint32_t val,
                       MemOpIdx oi, uintptr_t retaddr)
{
    full_be_stl_mmu(env, addr, val, oi, retaddr);
}

void helper_le_stq_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                       MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_LEUQ);
    store_helper(env, addr, val, oi, retaddr, MO_LEUQ);
}

void helper_be_stq_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                       MemOpIdx oi, uintptr_t retaddr)
{
    validate_memop(oi, MO_BEUQ);
    store_helper(env, addr, val, oi, retaddr, MO_BEUQ);
}

/*
 * Store Helpers for cpu_ldst.h
 */

typedef void FullStoreHelper(CPUArchState *env, target_ulong addr,
                             uint64_t val, MemOpIdx oi, uintptr_t retaddr);

static inline void cpu_store_helper(CPUArchState *env, target_ulong addr,
                                    uint64_t val, MemOpIdx oi, uintptr_t ra,
                                    FullStoreHelper *full_store)
{
    full_store(env, addr, val, oi, ra);
    qemu_plugin_vcpu_mem_cb(env_cpu(env), addr, oi, QEMU_PLUGIN_MEM_W);
}

void cpu_stb_mmu(CPUArchState *env, target_ulong addr, uint8_t val,
                 MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, full_stb_mmu);
}

void cpu_stw_be_mmu(CPUArchState *env, target_ulong addr, uint16_t val,
                    MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, full_be_stw_mmu);
}

void cpu_stl_be_mmu(CPUArchState *env, target_ulong addr, uint32_t val,
                    MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, full_be_stl_mmu);
}

void cpu_stq_be_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                    MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, helper_be_stq_mmu);
}

void cpu_stw_le_mmu(CPUArchState *env, target_ulong addr, uint16_t val,
                    MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, full_le_stw_mmu);
}

void cpu_stl_le_mmu(CPUArchState *env, target_ulong addr, uint32_t val,
                    MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, full_le_stl_mmu);
}

void cpu_stq_le_mmu(CPUArchState *env, target_ulong addr, uint64_t val,
                    MemOpIdx oi, uintptr_t retaddr)
{
    cpu_store_helper(env, addr, val, oi, retaddr, helper_le_stq_mmu);
}

#include "ldst_common.c.inc"

/*
 * First set of functions passes in OI and RETADDR.
 * This makes them callable from other helpers.
 */

#define ATOMIC_NAME(X) \
    glue(glue(glue(cpu_atomic_ ## X, SUFFIX), END), _mmu)

#define ATOMIC_MMU_CLEANUP

#include "atomic_common.c.inc"

#define DATA_SIZE 1
#include "atomic_template.h"

#define DATA_SIZE 2
#include "atomic_template.h"

#define DATA_SIZE 4
#include "atomic_template.h"

#ifdef CONFIG_ATOMIC64
#define DATA_SIZE 8
#include "atomic_template.h"
#endif

#if HAVE_CMPXCHG128 || HAVE_ATOMIC128
#define DATA_SIZE 16
#include "atomic_template.h"
#endif

/* Code access functions.  */

static uint64_t full_ldub_code(CPUArchState *env, target_ulong addr,
                               MemOpIdx oi, uintptr_t retaddr)
{
    return load_helper(env, addr, oi, retaddr, MO_8, true, full_ldub_code);
}

uint32_t cpu_ldub_code(CPUArchState *env, abi_ptr addr)
{
    MemOpIdx oi = make_memop_idx(MO_UB, cpu_mmu_index(env, true));
    return full_ldub_code(env, addr, oi, 0);
}

static uint64_t full_lduw_code(CPUArchState *env, target_ulong addr,
                               MemOpIdx oi, uintptr_t retaddr)
{
    return load_helper(env, addr, oi, retaddr, MO_TEUW, true, full_lduw_code);
}

uint32_t cpu_lduw_code(CPUArchState *env, abi_ptr addr)
{
    MemOpIdx oi = make_memop_idx(MO_TEUW, cpu_mmu_index(env, true));
    return full_lduw_code(env, addr, oi, 0);
}

static uint64_t full_ldl_code(CPUArchState *env, target_ulong addr,
                              MemOpIdx oi, uintptr_t retaddr)
{
    return load_helper(env, addr, oi, retaddr, MO_TEUL, true, full_ldl_code);
}

uint32_t cpu_ldl_code(CPUArchState *env, abi_ptr addr)
{
    MemOpIdx oi = make_memop_idx(MO_TEUL, cpu_mmu_index(env, true));
    return full_ldl_code(env, addr, oi, 0);
}

static uint64_t full_ldq_code(CPUArchState *env, target_ulong addr,
                              MemOpIdx oi, uintptr_t retaddr)
{
    return load_helper(env, addr, oi, retaddr, MO_TEUQ, true, full_ldq_code);
}

uint64_t cpu_ldq_code(CPUArchState *env, abi_ptr addr)
{
    MemOpIdx oi = make_memop_idx(MO_TEUQ, cpu_mmu_index(env, true));
    return full_ldq_code(env, addr, oi, 0);
}