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-rw-r--r--memory.c1141
1 files changed, 1141 insertions, 0 deletions
diff --git a/memory.c b/memory.c
new file mode 100644
index 0000000000..5c6e63df3f
--- /dev/null
+++ b/memory.c
@@ -0,0 +1,1141 @@
+/*
+ * Physical memory management
+ *
+ * Copyright 2011 Red Hat, Inc. and/or its affiliates
+ *
+ * Authors:
+ *  Avi Kivity <avi@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "memory.h"
+#include "exec-memory.h"
+#include "ioport.h"
+#include "bitops.h"
+#include "kvm.h"
+#include <assert.h>
+
+unsigned memory_region_transaction_depth = 0;
+
+typedef struct AddrRange AddrRange;
+
+struct AddrRange {
+    uint64_t start;
+    uint64_t size;
+};
+
+static AddrRange addrrange_make(uint64_t start, uint64_t size)
+{
+    return (AddrRange) { start, size };
+}
+
+static bool addrrange_equal(AddrRange r1, AddrRange r2)
+{
+    return r1.start == r2.start && r1.size == r2.size;
+}
+
+static uint64_t addrrange_end(AddrRange r)
+{
+    return r.start + r.size;
+}
+
+static AddrRange addrrange_shift(AddrRange range, int64_t delta)
+{
+    range.start += delta;
+    return range;
+}
+
+static bool addrrange_intersects(AddrRange r1, AddrRange r2)
+{
+    return (r1.start >= r2.start && r1.start < r2.start + r2.size)
+        || (r2.start >= r1.start && r2.start < r1.start + r1.size);
+}
+
+static AddrRange addrrange_intersection(AddrRange r1, AddrRange r2)
+{
+    uint64_t start = MAX(r1.start, r2.start);
+    /* off-by-one arithmetic to prevent overflow */
+    uint64_t end = MIN(addrrange_end(r1) - 1, addrrange_end(r2) - 1);
+    return addrrange_make(start, end - start + 1);
+}
+
+struct CoalescedMemoryRange {
+    AddrRange addr;
+    QTAILQ_ENTRY(CoalescedMemoryRange) link;
+};
+
+struct MemoryRegionIoeventfd {
+    AddrRange addr;
+    bool match_data;
+    uint64_t data;
+    int fd;
+};
+
+static bool memory_region_ioeventfd_before(MemoryRegionIoeventfd a,
+                                           MemoryRegionIoeventfd b)
+{
+    if (a.addr.start < b.addr.start) {
+        return true;
+    } else if (a.addr.start > b.addr.start) {
+        return false;
+    } else if (a.addr.size < b.addr.size) {
+        return true;
+    } else if (a.addr.size > b.addr.size) {
+        return false;
+    } else if (a.match_data < b.match_data) {
+        return true;
+    } else  if (a.match_data > b.match_data) {
+        return false;
+    } else if (a.match_data) {
+        if (a.data < b.data) {
+            return true;
+        } else if (a.data > b.data) {
+            return false;
+        }
+    }
+    if (a.fd < b.fd) {
+        return true;
+    } else if (a.fd > b.fd) {
+        return false;
+    }
+    return false;
+}
+
+static bool memory_region_ioeventfd_equal(MemoryRegionIoeventfd a,
+                                          MemoryRegionIoeventfd b)
+{
+    return !memory_region_ioeventfd_before(a, b)
+        && !memory_region_ioeventfd_before(b, a);
+}
+
+typedef struct FlatRange FlatRange;
+typedef struct FlatView FlatView;
+
+/* Range of memory in the global map.  Addresses are absolute. */
+struct FlatRange {
+    MemoryRegion *mr;
+    target_phys_addr_t offset_in_region;
+    AddrRange addr;
+    uint8_t dirty_log_mask;
+};
+
+/* Flattened global view of current active memory hierarchy.  Kept in sorted
+ * order.
+ */
+struct FlatView {
+    FlatRange *ranges;
+    unsigned nr;
+    unsigned nr_allocated;
+};
+
+typedef struct AddressSpace AddressSpace;
+typedef struct AddressSpaceOps AddressSpaceOps;
+
+/* A system address space - I/O, memory, etc. */
+struct AddressSpace {
+    const AddressSpaceOps *ops;
+    MemoryRegion *root;
+    FlatView current_map;
+    int ioeventfd_nb;
+    MemoryRegionIoeventfd *ioeventfds;
+};
+
+struct AddressSpaceOps {
+    void (*range_add)(AddressSpace *as, FlatRange *fr);
+    void (*range_del)(AddressSpace *as, FlatRange *fr);
+    void (*log_start)(AddressSpace *as, FlatRange *fr);
+    void (*log_stop)(AddressSpace *as, FlatRange *fr);
+    void (*ioeventfd_add)(AddressSpace *as, MemoryRegionIoeventfd *fd);
+    void (*ioeventfd_del)(AddressSpace *as, MemoryRegionIoeventfd *fd);
+};
+
+#define FOR_EACH_FLAT_RANGE(var, view)          \
+    for (var = (view)->ranges; var < (view)->ranges + (view)->nr; ++var)
+
+static bool flatrange_equal(FlatRange *a, FlatRange *b)
+{
+    return a->mr == b->mr
+        && addrrange_equal(a->addr, b->addr)
+        && a->offset_in_region == b->offset_in_region;
+}
+
+static void flatview_init(FlatView *view)
+{
+    view->ranges = NULL;
+    view->nr = 0;
+    view->nr_allocated = 0;
+}
+
+/* Insert a range into a given position.  Caller is responsible for maintaining
+ * sorting order.
+ */
+static void flatview_insert(FlatView *view, unsigned pos, FlatRange *range)
+{
+    if (view->nr == view->nr_allocated) {
+        view->nr_allocated = MAX(2 * view->nr, 10);
+        view->ranges = qemu_realloc(view->ranges,
+                                    view->nr_allocated * sizeof(*view->ranges));
+    }
+    memmove(view->ranges + pos + 1, view->ranges + pos,
+            (view->nr - pos) * sizeof(FlatRange));
+    view->ranges[pos] = *range;
+    ++view->nr;
+}
+
+static void flatview_destroy(FlatView *view)
+{
+    qemu_free(view->ranges);
+}
+
+static bool can_merge(FlatRange *r1, FlatRange *r2)
+{
+    return addrrange_end(r1->addr) == r2->addr.start
+        && r1->mr == r2->mr
+        && r1->offset_in_region + r1->addr.size == r2->offset_in_region
+        && r1->dirty_log_mask == r2->dirty_log_mask;
+}
+
+/* Attempt to simplify a view by merging ajacent ranges */
+static void flatview_simplify(FlatView *view)
+{
+    unsigned i, j;
+
+    i = 0;
+    while (i < view->nr) {
+        j = i + 1;
+        while (j < view->nr
+               && can_merge(&view->ranges[j-1], &view->ranges[j])) {
+            view->ranges[i].addr.size += view->ranges[j].addr.size;
+            ++j;
+        }
+        ++i;
+        memmove(&view->ranges[i], &view->ranges[j],
+                (view->nr - j) * sizeof(view->ranges[j]));
+        view->nr -= j - i;
+    }
+}
+
+static void memory_region_prepare_ram_addr(MemoryRegion *mr);
+
+static void as_memory_range_add(AddressSpace *as, FlatRange *fr)
+{
+    ram_addr_t phys_offset, region_offset;
+
+    memory_region_prepare_ram_addr(fr->mr);
+
+    phys_offset = fr->mr->ram_addr;
+    region_offset = fr->offset_in_region;
+    /* cpu_register_physical_memory_log() wants region_offset for
+     * mmio, but prefers offseting phys_offset for RAM.  Humour it.
+     */
+    if ((phys_offset & ~TARGET_PAGE_MASK) <= IO_MEM_ROM) {
+        phys_offset += region_offset;
+        region_offset = 0;
+    }
+
+    cpu_register_physical_memory_log(fr->addr.start,
+                                     fr->addr.size,
+                                     phys_offset,
+                                     region_offset,
+                                     fr->dirty_log_mask);
+}
+
+static void as_memory_range_del(AddressSpace *as, FlatRange *fr)
+{
+    cpu_register_physical_memory(fr->addr.start, fr->addr.size,
+                                 IO_MEM_UNASSIGNED);
+}
+
+static void as_memory_log_start(AddressSpace *as, FlatRange *fr)
+{
+    cpu_physical_log_start(fr->addr.start, fr->addr.size);
+}
+
+static void as_memory_log_stop(AddressSpace *as, FlatRange *fr)
+{
+    cpu_physical_log_stop(fr->addr.start, fr->addr.size);
+}
+
+static void as_memory_ioeventfd_add(AddressSpace *as, MemoryRegionIoeventfd *fd)
+{
+    int r;
+
+    assert(fd->match_data && fd->addr.size == 4);
+
+    r = kvm_set_ioeventfd_mmio_long(fd->fd, fd->addr.start, fd->data, true);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static void as_memory_ioeventfd_del(AddressSpace *as, MemoryRegionIoeventfd *fd)
+{
+    int r;
+
+    r = kvm_set_ioeventfd_mmio_long(fd->fd, fd->addr.start, fd->data, false);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static const AddressSpaceOps address_space_ops_memory = {
+    .range_add = as_memory_range_add,
+    .range_del = as_memory_range_del,
+    .log_start = as_memory_log_start,
+    .log_stop = as_memory_log_stop,
+    .ioeventfd_add = as_memory_ioeventfd_add,
+    .ioeventfd_del = as_memory_ioeventfd_del,
+};
+
+static AddressSpace address_space_memory = {
+    .ops = &address_space_ops_memory,
+};
+
+static const MemoryRegionPortio *find_portio(MemoryRegion *mr, uint64_t offset,
+                                             unsigned width, bool write)
+{
+    const MemoryRegionPortio *mrp;
+
+    for (mrp = mr->ops->old_portio; mrp->size; ++mrp) {
+        if (offset >= mrp->offset && offset < mrp->offset + mrp->len
+            && width == mrp->size
+            && (write ? (bool)mrp->write : (bool)mrp->read)) {
+            return mrp;
+        }
+    }
+    return NULL;
+}
+
+static void memory_region_iorange_read(IORange *iorange,
+                                       uint64_t offset,
+                                       unsigned width,
+                                       uint64_t *data)
+{
+    MemoryRegion *mr = container_of(iorange, MemoryRegion, iorange);
+
+    if (mr->ops->old_portio) {
+        const MemoryRegionPortio *mrp = find_portio(mr, offset, width, false);
+
+        *data = ((uint64_t)1 << (width * 8)) - 1;
+        if (mrp) {
+            *data = mrp->read(mr->opaque, offset - mrp->offset);
+        }
+        return;
+    }
+    *data = mr->ops->read(mr->opaque, offset, width);
+}
+
+static void memory_region_iorange_write(IORange *iorange,
+                                        uint64_t offset,
+                                        unsigned width,
+                                        uint64_t data)
+{
+    MemoryRegion *mr = container_of(iorange, MemoryRegion, iorange);
+
+    if (mr->ops->old_portio) {
+        const MemoryRegionPortio *mrp = find_portio(mr, offset, width, true);
+
+        if (mrp) {
+            mrp->write(mr->opaque, offset - mrp->offset, data);
+        }
+        return;
+    }
+    mr->ops->write(mr->opaque, offset, data, width);
+}
+
+static const IORangeOps memory_region_iorange_ops = {
+    .read = memory_region_iorange_read,
+    .write = memory_region_iorange_write,
+};
+
+static void as_io_range_add(AddressSpace *as, FlatRange *fr)
+{
+    iorange_init(&fr->mr->iorange, &memory_region_iorange_ops,
+                 fr->addr.start,fr->addr.size);
+    ioport_register(&fr->mr->iorange);
+}
+
+static void as_io_range_del(AddressSpace *as, FlatRange *fr)
+{
+    isa_unassign_ioport(fr->addr.start, fr->addr.size);
+}
+
+static void as_io_ioeventfd_add(AddressSpace *as, MemoryRegionIoeventfd *fd)
+{
+    int r;
+
+    assert(fd->match_data && fd->addr.size == 2);
+
+    r = kvm_set_ioeventfd_pio_word(fd->fd, fd->addr.start, fd->data, true);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static void as_io_ioeventfd_del(AddressSpace *as, MemoryRegionIoeventfd *fd)
+{
+    int r;
+
+    r = kvm_set_ioeventfd_pio_word(fd->fd, fd->addr.start, fd->data, false);
+    if (r < 0) {
+        abort();
+    }
+}
+
+static const AddressSpaceOps address_space_ops_io = {
+    .range_add = as_io_range_add,
+    .range_del = as_io_range_del,
+    .ioeventfd_add = as_io_ioeventfd_add,
+    .ioeventfd_del = as_io_ioeventfd_del,
+};
+
+static AddressSpace address_space_io = {
+    .ops = &address_space_ops_io,
+};
+
+/* Render a memory region into the global view.  Ranges in @view obscure
+ * ranges in @mr.
+ */
+static void render_memory_region(FlatView *view,
+                                 MemoryRegion *mr,
+                                 target_phys_addr_t base,
+                                 AddrRange clip)
+{
+    MemoryRegion *subregion;
+    unsigned i;
+    target_phys_addr_t offset_in_region;
+    uint64_t remain;
+    uint64_t now;
+    FlatRange fr;
+    AddrRange tmp;
+
+    base += mr->addr;
+
+    tmp = addrrange_make(base, mr->size);
+
+    if (!addrrange_intersects(tmp, clip)) {
+        return;
+    }
+
+    clip = addrrange_intersection(tmp, clip);
+
+    if (mr->alias) {
+        base -= mr->alias->addr;
+        base -= mr->alias_offset;
+        render_memory_region(view, mr->alias, base, clip);
+        return;
+    }
+
+    /* Render subregions in priority order. */
+    QTAILQ_FOREACH(subregion, &mr->subregions, subregions_link) {
+        render_memory_region(view, subregion, base, clip);
+    }
+
+    if (!mr->terminates) {
+        return;
+    }
+
+    offset_in_region = clip.start - base;
+    base = clip.start;
+    remain = clip.size;
+
+    /* Render the region itself into any gaps left by the current view. */
+    for (i = 0; i < view->nr && remain; ++i) {
+        if (base >= addrrange_end(view->ranges[i].addr)) {
+            continue;
+        }
+        if (base < view->ranges[i].addr.start) {
+            now = MIN(remain, view->ranges[i].addr.start - base);
+            fr.mr = mr;
+            fr.offset_in_region = offset_in_region;
+            fr.addr = addrrange_make(base, now);
+            fr.dirty_log_mask = mr->dirty_log_mask;
+            flatview_insert(view, i, &fr);
+            ++i;
+            base += now;
+            offset_in_region += now;
+            remain -= now;
+        }
+        if (base == view->ranges[i].addr.start) {
+            now = MIN(remain, view->ranges[i].addr.size);
+            base += now;
+            offset_in_region += now;
+            remain -= now;
+        }
+    }
+    if (remain) {
+        fr.mr = mr;
+        fr.offset_in_region = offset_in_region;
+        fr.addr = addrrange_make(base, remain);
+        fr.dirty_log_mask = mr->dirty_log_mask;
+        flatview_insert(view, i, &fr);
+    }
+}
+
+/* Render a memory topology into a list of disjoint absolute ranges. */
+static FlatView generate_memory_topology(MemoryRegion *mr)
+{
+    FlatView view;
+
+    flatview_init(&view);
+
+    render_memory_region(&view, mr, 0, addrrange_make(0, UINT64_MAX));
+    flatview_simplify(&view);
+
+    return view;
+}
+
+static void address_space_add_del_ioeventfds(AddressSpace *as,
+                                             MemoryRegionIoeventfd *fds_new,
+                                             unsigned fds_new_nb,
+                                             MemoryRegionIoeventfd *fds_old,
+                                             unsigned fds_old_nb)
+{
+    unsigned iold, inew;
+
+    /* Generate a symmetric difference of the old and new fd sets, adding
+     * and deleting as necessary.
+     */
+
+    iold = inew = 0;
+    while (iold < fds_old_nb || inew < fds_new_nb) {
+        if (iold < fds_old_nb
+            && (inew == fds_new_nb
+                || memory_region_ioeventfd_before(fds_old[iold],
+                                                  fds_new[inew]))) {
+            as->ops->ioeventfd_del(as, &fds_old[iold]);
+            ++iold;
+        } else if (inew < fds_new_nb
+                   && (iold == fds_old_nb
+                       || memory_region_ioeventfd_before(fds_new[inew],
+                                                         fds_old[iold]))) {
+            as->ops->ioeventfd_add(as, &fds_new[inew]);
+            ++inew;
+        } else {
+            ++iold;
+            ++inew;
+        }
+    }
+}
+
+static void address_space_update_ioeventfds(AddressSpace *as)
+{
+    FlatRange *fr;
+    unsigned ioeventfd_nb = 0;
+    MemoryRegionIoeventfd *ioeventfds = NULL;
+    AddrRange tmp;
+    unsigned i;
+
+    FOR_EACH_FLAT_RANGE(fr, &as->current_map) {
+        for (i = 0; i < fr->mr->ioeventfd_nb; ++i) {
+            tmp = addrrange_shift(fr->mr->ioeventfds[i].addr,
+                                  fr->addr.start - fr->offset_in_region);
+            if (addrrange_intersects(fr->addr, tmp)) {
+                ++ioeventfd_nb;
+                ioeventfds = qemu_realloc(ioeventfds,
+                                          ioeventfd_nb * sizeof(*ioeventfds));
+                ioeventfds[ioeventfd_nb-1] = fr->mr->ioeventfds[i];
+                ioeventfds[ioeventfd_nb-1].addr = tmp;
+            }
+        }
+    }
+
+    address_space_add_del_ioeventfds(as, ioeventfds, ioeventfd_nb,
+                                     as->ioeventfds, as->ioeventfd_nb);
+
+    qemu_free(as->ioeventfds);
+    as->ioeventfds = ioeventfds;
+    as->ioeventfd_nb = ioeventfd_nb;
+}
+
+static void address_space_update_topology_pass(AddressSpace *as,
+                                               FlatView old_view,
+                                               FlatView new_view,
+                                               bool adding)
+{
+    unsigned iold, inew;
+    FlatRange *frold, *frnew;
+
+    /* Generate a symmetric difference of the old and new memory maps.
+     * Kill ranges in the old map, and instantiate ranges in the new map.
+     */
+    iold = inew = 0;
+    while (iold < old_view.nr || inew < new_view.nr) {
+        if (iold < old_view.nr) {
+            frold = &old_view.ranges[iold];
+        } else {
+            frold = NULL;
+        }
+        if (inew < new_view.nr) {
+            frnew = &new_view.ranges[inew];
+        } else {
+            frnew = NULL;
+        }
+
+        if (frold
+            && (!frnew
+                || frold->addr.start < frnew->addr.start
+                || (frold->addr.start == frnew->addr.start
+                    && !flatrange_equal(frold, frnew)))) {
+            /* In old, but (not in new, or in new but attributes changed). */
+
+            if (!adding) {
+                as->ops->range_del(as, frold);
+            }
+
+            ++iold;
+        } else if (frold && frnew && flatrange_equal(frold, frnew)) {
+            /* In both (logging may have changed) */
+
+            if (adding) {
+                if (frold->dirty_log_mask && !frnew->dirty_log_mask) {
+                    as->ops->log_stop(as, frnew);
+                } else if (frnew->dirty_log_mask && !frold->dirty_log_mask) {
+                    as->ops->log_start(as, frnew);
+                }
+            }
+
+            ++iold;
+            ++inew;
+        } else {
+            /* In new */
+
+            if (adding) {
+                as->ops->range_add(as, frnew);
+            }
+
+            ++inew;
+        }
+    }
+}
+
+
+static void address_space_update_topology(AddressSpace *as)
+{
+    FlatView old_view = as->current_map;
+    FlatView new_view = generate_memory_topology(as->root);
+
+    address_space_update_topology_pass(as, old_view, new_view, false);
+    address_space_update_topology_pass(as, old_view, new_view, true);
+
+    as->current_map = new_view;
+    flatview_destroy(&old_view);
+    address_space_update_ioeventfds(as);
+}
+
+static void memory_region_update_topology(void)
+{
+    if (memory_region_transaction_depth) {
+        return;
+    }
+
+    if (address_space_memory.root) {
+        address_space_update_topology(&address_space_memory);
+    }
+    if (address_space_io.root) {
+        address_space_update_topology(&address_space_io);
+    }
+}
+
+void memory_region_transaction_begin(void)
+{
+    ++memory_region_transaction_depth;
+}
+
+void memory_region_transaction_commit(void)
+{
+    assert(memory_region_transaction_depth);
+    --memory_region_transaction_depth;
+    memory_region_update_topology();
+}
+
+void memory_region_init(MemoryRegion *mr,
+                        const char *name,
+                        uint64_t size)
+{
+    mr->ops = NULL;
+    mr->parent = NULL;
+    mr->size = size;
+    mr->addr = 0;
+    mr->offset = 0;
+    mr->terminates = false;
+    mr->priority = 0;
+    mr->may_overlap = false;
+    mr->alias = NULL;
+    QTAILQ_INIT(&mr->subregions);
+    memset(&mr->subregions_link, 0, sizeof mr->subregions_link);
+    QTAILQ_INIT(&mr->coalesced);
+    mr->name = qemu_strdup(name);
+    mr->dirty_log_mask = 0;
+    mr->ioeventfd_nb = 0;
+    mr->ioeventfds = NULL;
+}
+
+static bool memory_region_access_valid(MemoryRegion *mr,
+                                       target_phys_addr_t addr,
+                                       unsigned size)
+{
+    if (!mr->ops->valid.unaligned && (addr & (size - 1))) {
+        return false;
+    }
+
+    /* Treat zero as compatibility all valid */
+    if (!mr->ops->valid.max_access_size) {
+        return true;
+    }
+
+    if (size > mr->ops->valid.max_access_size
+        || size < mr->ops->valid.min_access_size) {
+        return false;
+    }
+    return true;
+}
+
+static uint32_t memory_region_read_thunk_n(void *_mr,
+                                           target_phys_addr_t addr,
+                                           unsigned size)
+{
+    MemoryRegion *mr = _mr;
+    unsigned access_size, access_size_min, access_size_max;
+    uint64_t access_mask;
+    uint32_t data = 0, tmp;
+    unsigned i;
+
+    if (!memory_region_access_valid(mr, addr, size)) {
+        return -1U; /* FIXME: better signalling */
+    }
+
+    if (!mr->ops->read) {
+        return mr->ops->old_mmio.read[bitops_ffsl(size)](mr->opaque, addr);
+    }
+
+    /* FIXME: support unaligned access */
+
+    access_size_min = mr->ops->impl.min_access_size;
+    if (!access_size_min) {
+        access_size_min = 1;
+    }
+    access_size_max = mr->ops->impl.max_access_size;
+    if (!access_size_max) {
+        access_size_max = 4;
+    }
+    access_size = MAX(MIN(size, access_size_max), access_size_min);
+    access_mask = -1ULL >> (64 - access_size * 8);
+    addr += mr->offset;
+    for (i = 0; i < size; i += access_size) {
+        /* FIXME: big-endian support */
+        tmp = mr->ops->read(mr->opaque, addr + i, access_size);
+        data |= (tmp & access_mask) << (i * 8);
+    }
+
+    return data;
+}
+
+static void memory_region_write_thunk_n(void *_mr,
+                                        target_phys_addr_t addr,
+                                        unsigned size,
+                                        uint64_t data)
+{
+    MemoryRegion *mr = _mr;
+    unsigned access_size, access_size_min, access_size_max;
+    uint64_t access_mask;
+    unsigned i;
+
+    if (!memory_region_access_valid(mr, addr, size)) {
+        return; /* FIXME: better signalling */
+    }
+
+    if (!mr->ops->write) {
+        mr->ops->old_mmio.write[bitops_ffsl(size)](mr->opaque, addr, data);
+        return;
+    }
+
+    /* FIXME: support unaligned access */
+
+    access_size_min = mr->ops->impl.min_access_size;
+    if (!access_size_min) {
+        access_size_min = 1;
+    }
+    access_size_max = mr->ops->impl.max_access_size;
+    if (!access_size_max) {
+        access_size_max = 4;
+    }
+    access_size = MAX(MIN(size, access_size_max), access_size_min);
+    access_mask = -1ULL >> (64 - access_size * 8);
+    addr += mr->offset;
+    for (i = 0; i < size; i += access_size) {
+        /* FIXME: big-endian support */
+        mr->ops->write(mr->opaque, addr + i, (data >> (i * 8)) & access_mask,
+                       access_size);
+    }
+}
+
+static uint32_t memory_region_read_thunk_b(void *mr, target_phys_addr_t addr)
+{
+    return memory_region_read_thunk_n(mr, addr, 1);
+}
+
+static uint32_t memory_region_read_thunk_w(void *mr, target_phys_addr_t addr)
+{
+    return memory_region_read_thunk_n(mr, addr, 2);
+}
+
+static uint32_t memory_region_read_thunk_l(void *mr, target_phys_addr_t addr)
+{
+    return memory_region_read_thunk_n(mr, addr, 4);
+}
+
+static void memory_region_write_thunk_b(void *mr, target_phys_addr_t addr,
+                                        uint32_t data)
+{
+    memory_region_write_thunk_n(mr, addr, 1, data);
+}
+
+static void memory_region_write_thunk_w(void *mr, target_phys_addr_t addr,
+                                        uint32_t data)
+{
+    memory_region_write_thunk_n(mr, addr, 2, data);
+}
+
+static void memory_region_write_thunk_l(void *mr, target_phys_addr_t addr,
+                                        uint32_t data)
+{
+    memory_region_write_thunk_n(mr, addr, 4, data);
+}
+
+static CPUReadMemoryFunc * const memory_region_read_thunk[] = {
+    memory_region_read_thunk_b,
+    memory_region_read_thunk_w,
+    memory_region_read_thunk_l,
+};
+
+static CPUWriteMemoryFunc * const memory_region_write_thunk[] = {
+    memory_region_write_thunk_b,
+    memory_region_write_thunk_w,
+    memory_region_write_thunk_l,
+};
+
+static void memory_region_prepare_ram_addr(MemoryRegion *mr)
+{
+    if (mr->backend_registered) {
+        return;
+    }
+
+    mr->ram_addr = cpu_register_io_memory(memory_region_read_thunk,
+                                          memory_region_write_thunk,
+                                          mr,
+                                          mr->ops->endianness);
+    mr->backend_registered = true;
+}
+
+void memory_region_init_io(MemoryRegion *mr,
+                           const MemoryRegionOps *ops,
+                           void *opaque,
+                           const char *name,
+                           uint64_t size)
+{
+    memory_region_init(mr, name, size);
+    mr->ops = ops;
+    mr->opaque = opaque;
+    mr->terminates = true;
+    mr->backend_registered = false;
+}
+
+void memory_region_init_ram(MemoryRegion *mr,
+                            DeviceState *dev,
+                            const char *name,
+                            uint64_t size)
+{
+    memory_region_init(mr, name, size);
+    mr->terminates = true;
+    mr->ram_addr = qemu_ram_alloc(dev, name, size);
+    mr->backend_registered = true;
+}
+
+void memory_region_init_ram_ptr(MemoryRegion *mr,
+                                DeviceState *dev,
+                                const char *name,
+                                uint64_t size,
+                                void *ptr)
+{
+    memory_region_init(mr, name, size);
+    mr->terminates = true;
+    mr->ram_addr = qemu_ram_alloc_from_ptr(dev, name, size, ptr);
+    mr->backend_registered = true;
+}
+
+void memory_region_init_alias(MemoryRegion *mr,
+                              const char *name,
+                              MemoryRegion *orig,
+                              target_phys_addr_t offset,
+                              uint64_t size)
+{
+    memory_region_init(mr, name, size);
+    mr->alias = orig;
+    mr->alias_offset = offset;
+}
+
+void memory_region_destroy(MemoryRegion *mr)
+{
+    assert(QTAILQ_EMPTY(&mr->subregions));
+    memory_region_clear_coalescing(mr);
+    qemu_free((char *)mr->name);
+    qemu_free(mr->ioeventfds);
+}
+
+uint64_t memory_region_size(MemoryRegion *mr)
+{
+    return mr->size;
+}
+
+void memory_region_set_offset(MemoryRegion *mr, target_phys_addr_t offset)
+{
+    mr->offset = offset;
+}
+
+void memory_region_set_log(MemoryRegion *mr, bool log, unsigned client)
+{
+    uint8_t mask = 1 << client;
+
+    mr->dirty_log_mask = (mr->dirty_log_mask & ~mask) | (log * mask);
+    memory_region_update_topology();
+}
+
+bool memory_region_get_dirty(MemoryRegion *mr, target_phys_addr_t addr,
+                             unsigned client)
+{
+    assert(mr->terminates);
+    return cpu_physical_memory_get_dirty(mr->ram_addr + addr, 1 << client);
+}
+
+void memory_region_set_dirty(MemoryRegion *mr, target_phys_addr_t addr)
+{
+    assert(mr->terminates);
+    return cpu_physical_memory_set_dirty(mr->ram_addr + addr);
+}
+
+void memory_region_sync_dirty_bitmap(MemoryRegion *mr)
+{
+    FlatRange *fr;
+
+    FOR_EACH_FLAT_RANGE(fr, &address_space_memory.current_map) {
+        if (fr->mr == mr) {
+            cpu_physical_sync_dirty_bitmap(fr->addr.start,
+                                           fr->addr.start + fr->addr.size);
+        }
+    }
+}
+
+void memory_region_set_readonly(MemoryRegion *mr, bool readonly)
+{
+    /* FIXME */
+}
+
+void memory_region_reset_dirty(MemoryRegion *mr, target_phys_addr_t addr,
+                               target_phys_addr_t size, unsigned client)
+{
+    assert(mr->terminates);
+    cpu_physical_memory_reset_dirty(mr->ram_addr + addr,
+                                    mr->ram_addr + addr + size,
+                                    1 << client);
+}
+
+void *memory_region_get_ram_ptr(MemoryRegion *mr)
+{
+    if (mr->alias) {
+        return memory_region_get_ram_ptr(mr->alias) + mr->alias_offset;
+    }
+
+    assert(mr->terminates);
+
+    return qemu_get_ram_ptr(mr->ram_addr);
+}
+
+static void memory_region_update_coalesced_range(MemoryRegion *mr)
+{
+    FlatRange *fr;
+    CoalescedMemoryRange *cmr;
+    AddrRange tmp;
+
+    FOR_EACH_FLAT_RANGE(fr, &address_space_memory.current_map) {
+        if (fr->mr == mr) {
+            qemu_unregister_coalesced_mmio(fr->addr.start, fr->addr.size);
+            QTAILQ_FOREACH(cmr, &mr->coalesced, link) {
+                tmp = addrrange_shift(cmr->addr,
+                                      fr->addr.start - fr->offset_in_region);
+                if (!addrrange_intersects(tmp, fr->addr)) {
+                    continue;
+                }
+                tmp = addrrange_intersection(tmp, fr->addr);
+                qemu_register_coalesced_mmio(tmp.start, tmp.size);
+            }
+        }
+    }
+}
+
+void memory_region_set_coalescing(MemoryRegion *mr)
+{
+    memory_region_clear_coalescing(mr);
+    memory_region_add_coalescing(mr, 0, mr->size);
+}
+
+void memory_region_add_coalescing(MemoryRegion *mr,
+                                  target_phys_addr_t offset,
+                                  uint64_t size)
+{
+    CoalescedMemoryRange *cmr = qemu_malloc(sizeof(*cmr));
+
+    cmr->addr = addrrange_make(offset, size);
+    QTAILQ_INSERT_TAIL(&mr->coalesced, cmr, link);
+    memory_region_update_coalesced_range(mr);
+}
+
+void memory_region_clear_coalescing(MemoryRegion *mr)
+{
+    CoalescedMemoryRange *cmr;
+
+    while (!QTAILQ_EMPTY(&mr->coalesced)) {
+        cmr = QTAILQ_FIRST(&mr->coalesced);
+        QTAILQ_REMOVE(&mr->coalesced, cmr, link);
+        qemu_free(cmr);
+    }
+    memory_region_update_coalesced_range(mr);
+}
+
+void memory_region_add_eventfd(MemoryRegion *mr,
+                               target_phys_addr_t addr,
+                               unsigned size,
+                               bool match_data,
+                               uint64_t data,
+                               int fd)
+{
+    MemoryRegionIoeventfd mrfd = {
+        .addr.start = addr,
+        .addr.size = size,
+        .match_data = match_data,
+        .data = data,
+        .fd = fd,
+    };
+    unsigned i;
+
+    for (i = 0; i < mr->ioeventfd_nb; ++i) {
+        if (memory_region_ioeventfd_before(mrfd, mr->ioeventfds[i])) {
+            break;
+        }
+    }
+    ++mr->ioeventfd_nb;
+    mr->ioeventfds = qemu_realloc(mr->ioeventfds,
+                                  sizeof(*mr->ioeventfds) * mr->ioeventfd_nb);
+    memmove(&mr->ioeventfds[i+1], &mr->ioeventfds[i],
+            sizeof(*mr->ioeventfds) * (mr->ioeventfd_nb-1 - i));
+    mr->ioeventfds[i] = mrfd;
+    memory_region_update_topology();
+}
+
+void memory_region_del_eventfd(MemoryRegion *mr,
+                               target_phys_addr_t addr,
+                               unsigned size,
+                               bool match_data,
+                               uint64_t data,
+                               int fd)
+{
+    MemoryRegionIoeventfd mrfd = {
+        .addr.start = addr,
+        .addr.size = size,
+        .match_data = match_data,
+        .data = data,
+        .fd = fd,
+    };
+    unsigned i;
+
+    for (i = 0; i < mr->ioeventfd_nb; ++i) {
+        if (memory_region_ioeventfd_equal(mrfd, mr->ioeventfds[i])) {
+            break;
+        }
+    }
+    assert(i != mr->ioeventfd_nb);
+    memmove(&mr->ioeventfds[i], &mr->ioeventfds[i+1],
+            sizeof(*mr->ioeventfds) * (mr->ioeventfd_nb - (i+1)));
+    --mr->ioeventfd_nb;
+    mr->ioeventfds = qemu_realloc(mr->ioeventfds,
+                                  sizeof(*mr->ioeventfds)*mr->ioeventfd_nb + 1);
+    memory_region_update_topology();
+}
+
+static void memory_region_add_subregion_common(MemoryRegion *mr,
+                                               target_phys_addr_t offset,
+                                               MemoryRegion *subregion)
+{
+    MemoryRegion *other;
+
+    assert(!subregion->parent);
+    subregion->parent = mr;
+    subregion->addr = offset;
+    QTAILQ_FOREACH(other, &mr->subregions, subregions_link) {
+        if (subregion->may_overlap || other->may_overlap) {
+            continue;
+        }
+        if (offset >= other->offset + other->size
+            || offset + subregion->size <= other->offset) {
+            continue;
+        }
+        printf("warning: subregion collision %llx/%llx vs %llx/%llx\n",
+               (unsigned long long)offset,
+               (unsigned long long)subregion->size,
+               (unsigned long long)other->offset,
+               (unsigned long long)other->size);
+    }
+    QTAILQ_FOREACH(other, &mr->subregions, subregions_link) {
+        if (subregion->priority >= other->priority) {
+            QTAILQ_INSERT_BEFORE(other, subregion, subregions_link);
+            goto done;
+        }
+    }
+    QTAILQ_INSERT_TAIL(&mr->subregions, subregion, subregions_link);
+done:
+    memory_region_update_topology();
+}
+
+
+void memory_region_add_subregion(MemoryRegion *mr,
+                                 target_phys_addr_t offset,
+                                 MemoryRegion *subregion)
+{
+    subregion->may_overlap = false;
+    subregion->priority = 0;
+    memory_region_add_subregion_common(mr, offset, subregion);
+}
+
+void memory_region_add_subregion_overlap(MemoryRegion *mr,
+                                         target_phys_addr_t offset,
+                                         MemoryRegion *subregion,
+                                         unsigned priority)
+{
+    subregion->may_overlap = true;
+    subregion->priority = priority;
+    memory_region_add_subregion_common(mr, offset, subregion);
+}
+
+void memory_region_del_subregion(MemoryRegion *mr,
+                                 MemoryRegion *subregion)
+{
+    assert(subregion->parent == mr);
+    subregion->parent = NULL;
+    QTAILQ_REMOVE(&mr->subregions, subregion, subregions_link);
+    memory_region_update_topology();
+}
+
+void set_system_memory_map(MemoryRegion *mr)
+{
+    address_space_memory.root = mr;
+    memory_region_update_topology();
+}
+
+void set_system_io_map(MemoryRegion *mr)
+{
+    address_space_io.root = mr;
+    memory_region_update_topology();
+}