vfio: Generalize region support

Both platform and PCI vfio drivers create a "slow", I/O memory region
with one or more mmap memory regions overlayed when supported by the
device. Generalize this to a set of common helpers in the core that
pulls the region info from vfio, fills the region data, configures
slow mapping, and adds helpers for comleting the mmap, enable/disable,
and teardown.  This can be immediately used by the PCI MSI-X code,
which needs to mmap around the MSI-X vector table.

This also changes VFIORegion.mem to be dynamically allocated because
otherwise we don't know how the caller has allocated VFIORegion and
therefore don't know whether to unreference it to destroy the
MemoryRegion or not.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

4 files changed, 258 insertions, 178 deletions

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index e20fc4f794..96ccb797fe 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -493,46 +493,162 @@ static void vfio_listener_release(VFIOContainer *container)
     memory_listener_unregister(&container->listener);
 }
 
-int vfio_mmap_region(Object *obj, VFIORegion *region,
-                     MemoryRegion *mem, MemoryRegion *submem,
-                     void **map, size_t size, off_t offset,
-                     const char *name)
+int vfio_region_setup(Object *obj, VFIODevice *vbasedev, VFIORegion *region,
+                      int index, const char *name)
 {
-    int ret = 0;
-    VFIODevice *vbasedev = region->vbasedev;
+    struct vfio_region_info *info;
+    int ret;
+
+    ret = vfio_get_region_info(vbasedev, index, &info);
+    if (ret) {
+        return ret;
+    }
+
+    region->vbasedev = vbasedev;
+    region->flags = info->flags;
+    region->size = info->size;
+    region->fd_offset = info->offset;
+    region->nr = index;
 
-    if (!vbasedev->no_mmap && size && region->flags &
-        VFIO_REGION_INFO_FLAG_MMAP) {
-        int prot = 0;
+    if (region->size) {
+        region->mem = g_new0(MemoryRegion, 1);
+        memory_region_init_io(region->mem, obj, &vfio_region_ops,
+                              region, name, region->size);
 
-        if (region->flags & VFIO_REGION_INFO_FLAG_READ) {
-            prot |= PROT_READ;
+        if (!vbasedev->no_mmap &&
+            region->flags & VFIO_REGION_INFO_FLAG_MMAP &&
+            !(region->size & ~qemu_real_host_page_mask)) {
+
+            region->nr_mmaps = 1;
+            region->mmaps = g_new0(VFIOMmap, region->nr_mmaps);
+
+            region->mmaps[0].offset = 0;
+            region->mmaps[0].size = region->size;
         }
+    }
+
+    g_free(info);
+
+    trace_vfio_region_setup(vbasedev->name, index, name,
+                            region->flags, region->fd_offset, region->size);
+    return 0;
+}
 
-        if (region->flags & VFIO_REGION_INFO_FLAG_WRITE) {
-            prot |= PROT_WRITE;
+int vfio_region_mmap(VFIORegion *region)
+{
+    int i, prot = 0;
+    char *name;
+
+    if (!region->mem) {
+        return 0;
+    }
+
+    prot |= region->flags & VFIO_REGION_INFO_FLAG_READ ? PROT_READ : 0;
+    prot |= region->flags & VFIO_REGION_INFO_FLAG_WRITE ? PROT_WRITE : 0;
+
+    for (i = 0; i < region->nr_mmaps; i++) {
+        region->mmaps[i].mmap = mmap(NULL, region->mmaps[i].size, prot,
+                                     MAP_SHARED, region->vbasedev->fd,
+                                     region->fd_offset +
+                                     region->mmaps[i].offset);
+        if (region->mmaps[i].mmap == MAP_FAILED) {
+            int ret = -errno;
+
+            trace_vfio_region_mmap_fault(memory_region_name(region->mem), i,
+                                         region->fd_offset +
+                                         region->mmaps[i].offset,
+                                         region->fd_offset +
+                                         region->mmaps[i].offset +
+                                         region->mmaps[i].size - 1, ret);
+
+            region->mmaps[i].mmap = NULL;
+
+            for (i--; i >= 0; i--) {
+                memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
+                munmap(region->mmaps[i].mmap, region->mmaps[i].size);
+                object_unparent(OBJECT(&region->mmaps[i].mem));
+                region->mmaps[i].mmap = NULL;
+            }
+
+            return ret;
         }
 
-        *map = mmap(NULL, size, prot, MAP_SHARED,
-                    vbasedev->fd,
-                    region->fd_offset + offset);
-        if (*map == MAP_FAILED) {
-            *map = NULL;
-            ret = -errno;
-            goto empty_region;
+        name = g_strdup_printf("%s mmaps[%d]",
+                               memory_region_name(region->mem), i);
+        memory_region_init_ram_ptr(&region->mmaps[i].mem,
+                                   memory_region_owner(region->mem),
+                                   name, region->mmaps[i].size,
+                                   region->mmaps[i].mmap);
+        g_free(name);
+        memory_region_set_skip_dump(&region->mmaps[i].mem);
+        memory_region_add_subregion(region->mem, region->mmaps[i].offset,
+                                    &region->mmaps[i].mem);
+
+        trace_vfio_region_mmap(memory_region_name(&region->mmaps[i].mem),
+                               region->mmaps[i].offset,
+                               region->mmaps[i].offset +
+                               region->mmaps[i].size - 1);
+    }
+
+    return 0;
+}
+
+void vfio_region_exit(VFIORegion *region)
+{
+    int i;
+
+    if (!region->mem) {
+        return;
+    }
+
+    for (i = 0; i < region->nr_mmaps; i++) {
+        if (region->mmaps[i].mmap) {
+            memory_region_del_subregion(region->mem, &region->mmaps[i].mem);
         }
+    }
 
-        memory_region_init_ram_ptr(submem, obj, name, size, *map);
-        memory_region_set_skip_dump(submem);
-    } else {
-empty_region:
-        /* Create a zero sized sub-region to make cleanup easy. */
-        memory_region_init(submem, obj, name, 0);
+    trace_vfio_region_exit(region->vbasedev->name, region->nr);
+}
+
+void vfio_region_finalize(VFIORegion *region)
+{
+    int i;
+
+    if (!region->mem) {
+        return;
     }
 
-    memory_region_add_subregion(mem, offset, submem);
+    for (i = 0; i < region->nr_mmaps; i++) {
+        if (region->mmaps[i].mmap) {
+            munmap(region->mmaps[i].mmap, region->mmaps[i].size);
+            object_unparent(OBJECT(&region->mmaps[i].mem));
+        }
+    }
 
-    return ret;
+    object_unparent(OBJECT(region->mem));
+
+    g_free(region->mem);
+    g_free(region->mmaps);
+
+    trace_vfio_region_finalize(region->vbasedev->name, region->nr);
+}
+
+void vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
+{
+    int i;
+
+    if (!region->mem) {
+        return;
+    }
+
+    for (i = 0; i < region->nr_mmaps; i++) {
+        if (region->mmaps[i].mmap) {
+            memory_region_set_enabled(&region->mmaps[i].mem, enabled);
+        }
+    }
+
+    trace_vfio_region_mmaps_set_enabled(memory_region_name(region->mem),
+                                        enabled);
 }
 
 void vfio_reset_handler(void *opaque)
diff --git a/hw/vfio/pci-quirks.c b/hw/vfio/pci-quirks.c
index 48155277c6..d626ec93ad 100644
--- a/hw/vfio/pci-quirks.c
+++ b/hw/vfio/pci-quirks.c
@@ -337,14 +337,14 @@ static void vfio_probe_ati_bar4_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(window->addr_mem, OBJECT(vdev),
                           &vfio_generic_window_address_quirk, window,
                           "vfio-ati-bar4-window-address-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         window->address_offset,
                                         window->addr_mem, 1);
 
     memory_region_init_io(window->data_mem, OBJECT(vdev),
                           &vfio_generic_window_data_quirk, window,
                           "vfio-ati-bar4-window-data-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         window->data_offset,
                                         window->data_mem, 1);
 
@@ -378,7 +378,7 @@ static void vfio_probe_ati_bar2_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(mirror->mem, OBJECT(vdev),
                           &vfio_generic_mirror_quirk, mirror,
                           "vfio-ati-bar2-4000-quirk", PCI_CONFIG_SPACE_SIZE);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         mirror->offset, mirror->mem, 1);
 
     QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, quirk, next);
@@ -683,7 +683,7 @@ static void vfio_probe_nvidia_bar5_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(window->addr_mem, OBJECT(vdev),
                           &vfio_generic_window_address_quirk, window,
                           "vfio-nvidia-bar5-window-address-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         window->address_offset,
                                         window->addr_mem, 1);
     memory_region_set_enabled(window->addr_mem, false);
@@ -691,7 +691,7 @@ static void vfio_probe_nvidia_bar5_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(window->data_mem, OBJECT(vdev),
                           &vfio_generic_window_data_quirk, window,
                           "vfio-nvidia-bar5-window-data-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         window->data_offset,
                                         window->data_mem, 1);
     memory_region_set_enabled(window->data_mem, false);
@@ -699,13 +699,13 @@ static void vfio_probe_nvidia_bar5_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(&quirk->mem[2], OBJECT(vdev),
                           &vfio_nvidia_bar5_quirk_master, bar5,
                           "vfio-nvidia-bar5-master-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         0, &quirk->mem[2], 1);
 
     memory_region_init_io(&quirk->mem[3], OBJECT(vdev),
                           &vfio_nvidia_bar5_quirk_enable, bar5,
                           "vfio-nvidia-bar5-enable-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         4, &quirk->mem[3], 1);
 
     QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, quirk, next);
@@ -767,7 +767,7 @@ static void vfio_probe_nvidia_bar0_quirk(VFIOPCIDevice *vdev, int nr)
                           &vfio_nvidia_mirror_quirk, mirror,
                           "vfio-nvidia-bar0-88000-mirror-quirk",
                           vdev->config_size);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         mirror->offset, mirror->mem, 1);
 
     QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, quirk, next);
@@ -786,7 +786,7 @@ static void vfio_probe_nvidia_bar0_quirk(VFIOPCIDevice *vdev, int nr)
                               &vfio_nvidia_mirror_quirk, mirror,
                               "vfio-nvidia-bar0-1800-mirror-quirk",
                               PCI_CONFIG_SPACE_SIZE);
-        memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+        memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                             mirror->offset, mirror->mem, 1);
 
         QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, quirk, next);
@@ -947,13 +947,13 @@ static void vfio_probe_rtl8168_bar2_quirk(VFIOPCIDevice *vdev, int nr)
     memory_region_init_io(&quirk->mem[0], OBJECT(vdev),
                           &vfio_rtl_address_quirk, rtl,
                           "vfio-rtl8168-window-address-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         0x74, &quirk->mem[0], 1);
 
     memory_region_init_io(&quirk->mem[1], OBJECT(vdev),
                           &vfio_rtl_data_quirk, rtl,
                           "vfio-rtl8168-window-data-quirk", 4);
-    memory_region_add_subregion_overlap(&vdev->bars[nr].region.mem,
+    memory_region_add_subregion_overlap(vdev->bars[nr].region.mem,
                                         0x70, &quirk->mem[1], 1);
 
     QLIST_INSERT_HEAD(&vdev->bars[nr].quirks, quirk, next);
@@ -1020,7 +1020,7 @@ void vfio_bar_quirk_teardown(VFIOPCIDevice *vdev, int nr)
 
     QLIST_FOREACH(quirk, &bar->quirks, next) {
         for (i = 0; i < quirk->nr_mem; i++) {
-            memory_region_del_subregion(&bar->region.mem, &quirk->mem[i]);
+            memory_region_del_subregion(bar->region.mem, &quirk->mem[i]);
         }
     }
 }
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index db7a95026a..f18a678cf9 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -1166,6 +1166,74 @@ static int vfio_msi_setup(VFIOPCIDevice *vdev, int pos)
     return 0;
 }
 
+static void vfio_pci_fixup_msix_region(VFIOPCIDevice *vdev)
+{
+    off_t start, end;
+    VFIORegion *region = &vdev->bars[vdev->msix->table_bar].region;
+
+    /*
+     * We expect to find a single mmap covering the whole BAR, anything else
+     * means it's either unsupported or already setup.
+     */
+    if (region->nr_mmaps != 1 || region->mmaps[0].offset ||
+        region->size != region->mmaps[0].size) {
+        return;
+    }
+
+    /* MSI-X table start and end aligned to host page size */
+    start = vdev->msix->table_offset & qemu_real_host_page_mask;
+    end = REAL_HOST_PAGE_ALIGN((uint64_t)vdev->msix->table_offset +
+                               (vdev->msix->entries * PCI_MSIX_ENTRY_SIZE));
+
+    /*
+     * Does the MSI-X table cover the beginning of the BAR?  The whole BAR?
+     * NB - Host page size is necessarily a power of two and so is the PCI
+     * BAR (not counting EA yet), therefore if we have host page aligned
+     * @start and @end, then any remainder of the BAR before or after those
+     * must be at least host page sized and therefore mmap'able.
+     */
+    if (!start) {
+        if (end >= region->size) {
+            region->nr_mmaps = 0;
+            g_free(region->mmaps);
+            region->mmaps = NULL;
+            trace_vfio_msix_fixup(vdev->vbasedev.name,
+                                  vdev->msix->table_bar, 0, 0);
+        } else {
+            region->mmaps[0].offset = end;
+            region->mmaps[0].size = region->size - end;
+            trace_vfio_msix_fixup(vdev->vbasedev.name,
+                              vdev->msix->table_bar, region->mmaps[0].offset,
+                              region->mmaps[0].offset + region->mmaps[0].size);
+        }
+
+    /* Maybe it's aligned at the end of the BAR */
+    } else if (end >= region->size) {
+        region->mmaps[0].size = start;
+        trace_vfio_msix_fixup(vdev->vbasedev.name,
+                              vdev->msix->table_bar, region->mmaps[0].offset,
+                              region->mmaps[0].offset + region->mmaps[0].size);
+
+    /* Otherwise it must split the BAR */
+    } else {
+        region->nr_mmaps = 2;
+        region->mmaps = g_renew(VFIOMmap, region->mmaps, 2);
+
+        memcpy(&region->mmaps[1], &region->mmaps[0], sizeof(VFIOMmap));
+
+        region->mmaps[0].size = start;
+        trace_vfio_msix_fixup(vdev->vbasedev.name,
+                              vdev->msix->table_bar, region->mmaps[0].offset,
+                              region->mmaps[0].offset + region->mmaps[0].size);
+
+        region->mmaps[1].offset = end;
+        region->mmaps[1].size = region->size - end;
+        trace_vfio_msix_fixup(vdev->vbasedev.name,
+                              vdev->msix->table_bar, region->mmaps[1].offset,
+                              region->mmaps[1].offset + region->mmaps[1].size);
+    }
+}
+
 /*
  * We don't have any control over how pci_add_capability() inserts
  * capabilities into the chain.  In order to setup MSI-X we need a
@@ -1240,6 +1308,8 @@ static int vfio_msix_early_setup(VFIOPCIDevice *vdev)
                                 msix->table_offset, msix->entries);
     vdev->msix = msix;
 
+    vfio_pci_fixup_msix_region(vdev);
+
     return 0;
 }
 
@@ -1250,9 +1320,9 @@ static int vfio_msix_setup(VFIOPCIDevice *vdev, int pos)
     vdev->msix->pending = g_malloc0(BITS_TO_LONGS(vdev->msix->entries) *
                                     sizeof(unsigned long));
     ret = msix_init(&vdev->pdev, vdev->msix->entries,
-                    &vdev->bars[vdev->msix->table_bar].region.mem,
+                    vdev->bars[vdev->msix->table_bar].region.mem,
                     vdev->msix->table_bar, vdev->msix->table_offset,
-                    &vdev->bars[vdev->msix->pba_bar].region.mem,
+                    vdev->bars[vdev->msix->pba_bar].region.mem,
                     vdev->msix->pba_bar, vdev->msix->pba_offset, pos);
     if (ret < 0) {
         if (ret == -ENOTSUP) {
@@ -1289,8 +1359,8 @@ static void vfio_teardown_msi(VFIOPCIDevice *vdev)
 
     if (vdev->msix) {
         msix_uninit(&vdev->pdev,
-                    &vdev->bars[vdev->msix->table_bar].region.mem,
-                    &vdev->bars[vdev->msix->pba_bar].region.mem);
+                    vdev->bars[vdev->msix->table_bar].region.mem,
+                    vdev->bars[vdev->msix->pba_bar].region.mem);
         g_free(vdev->msix->pending);
     }
 }
@@ -1303,16 +1373,7 @@ static void vfio_mmap_set_enabled(VFIOPCIDevice *vdev, bool enabled)
     int i;
 
     for (i = 0; i < PCI_ROM_SLOT; i++) {
-        VFIOBAR *bar = &vdev->bars[i];
-
-        if (!bar->region.size) {
-            continue;
-        }
-
-        memory_region_set_enabled(&bar->region.mmap_mem, enabled);
-        if (vdev->msix && vdev->msix->table_bar == i) {
-            memory_region_set_enabled(&vdev->msix->mmap_mem, enabled);
-        }
+        vfio_region_mmaps_set_enabled(&vdev->bars[i].region, enabled);
     }
 }
 
@@ -1326,11 +1387,7 @@ static void vfio_unregister_bar(VFIOPCIDevice *vdev, int nr)
 
     vfio_bar_quirk_teardown(vdev, nr);
 
-    memory_region_del_subregion(&bar->region.mem, &bar->region.mmap_mem);
-
-    if (vdev->msix && vdev->msix->table_bar == nr) {
-        memory_region_del_subregion(&bar->region.mem, &vdev->msix->mmap_mem);
-    }
+    vfio_region_exit(&bar->region);
 }
 
 static void vfio_unmap_bar(VFIOPCIDevice *vdev, int nr)
@@ -1343,18 +1400,13 @@ static void vfio_unmap_bar(VFIOPCIDevice *vdev, int nr)
 
     vfio_bar_quirk_free(vdev, nr);
 
-    munmap(bar->region.mmap, memory_region_size(&bar->region.mmap_mem));
-
-    if (vdev->msix && vdev->msix->table_bar == nr) {
-        munmap(vdev->msix->mmap, memory_region_size(&vdev->msix->mmap_mem));
-    }
+    vfio_region_finalize(&bar->region);
 }
 
 static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
 {
     VFIOBAR *bar = &vdev->bars[nr];
     uint64_t size = bar->region.size;
-    char name[64];
     uint32_t pci_bar;
     uint8_t type;
     int ret;
@@ -1364,8 +1416,6 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
         return;
     }
 
-    snprintf(name, sizeof(name), "VFIO %s BAR %d", vdev->vbasedev.name, nr);
-
     /* Determine what type of BAR this is for registration */
     ret = pread(vdev->vbasedev.fd, &pci_bar, sizeof(pci_bar),
                 vdev->config_offset + PCI_BASE_ADDRESS_0 + (4 * nr));
@@ -1380,41 +1430,11 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
     type = pci_bar & (bar->ioport ? ~PCI_BASE_ADDRESS_IO_MASK :
                                     ~PCI_BASE_ADDRESS_MEM_MASK);
 
-    /* A "slow" read/write mapping underlies all BARs */
-    memory_region_init_io(&bar->region.mem, OBJECT(vdev), &vfio_region_ops,
-                          bar, name, size);
-    pci_register_bar(&vdev->pdev, nr, type, &bar->region.mem);
-
-    /*
-     * We can't mmap areas overlapping the MSIX vector table, so we
-     * potentially insert a direct-mapped subregion before and after it.
-     */
-    if (vdev->msix && vdev->msix->table_bar == nr) {
-        size = vdev->msix->table_offset & qemu_real_host_page_mask;
-    }
-
-    strncat(name, " mmap", sizeof(name) - strlen(name) - 1);
-    if (vfio_mmap_region(OBJECT(vdev), &bar->region, &bar->region.mem,
-                      &bar->region.mmap_mem, &bar->region.mmap,
-                      size, 0, name)) {
-        error_report("%s unsupported. Performance may be slow", name);
-    }
-
-    if (vdev->msix && vdev->msix->table_bar == nr) {
-        uint64_t start;
-
-        start = REAL_HOST_PAGE_ALIGN((uint64_t)vdev->msix->table_offset +
-                                     (vdev->msix->entries *
-                                      PCI_MSIX_ENTRY_SIZE));
+    pci_register_bar(&vdev->pdev, nr, type, bar->region.mem);
 
-        size = start < bar->region.size ? bar->region.size - start : 0;
-        strncat(name, " msix-hi", sizeof(name) - strlen(name) - 1);
-        /* VFIOMSIXInfo contains another MemoryRegion for this mapping */
-        if (vfio_mmap_region(OBJECT(vdev), &bar->region, &bar->region.mem,
-                          &vdev->msix->mmap_mem,
-                          &vdev->msix->mmap, size, start, name)) {
-            error_report("%s unsupported. Performance may be slow", name);
-        }
+    if (vfio_region_mmap(&bar->region)) {
+        error_report("Failed to mmap %s BAR %d. Performance may be slow",
+                     vdev->vbasedev.name, nr);
     }
 
     vfio_bar_quirk_setup(vdev, nr);
@@ -2049,25 +2069,18 @@ static int vfio_populate_device(VFIOPCIDevice *vdev)
     }
 
     for (i = VFIO_PCI_BAR0_REGION_INDEX; i < VFIO_PCI_ROM_REGION_INDEX; i++) {
-        ret = vfio_get_region_info(vbasedev, i, &reg_info);
+        char *name = g_strdup_printf("%s BAR %d", vbasedev->name, i);
+
+        ret = vfio_region_setup(OBJECT(vdev), vbasedev,
+                                &vdev->bars[i].region, i, name);
+        g_free(name);
+
         if (ret) {
             error_report("vfio: Error getting region %d info: %m", i);
             goto error;
         }
 
-        trace_vfio_populate_device_region(vbasedev->name, i,
-                                          (unsigned long)reg_info->size,
-                                          (unsigned long)reg_info->offset,
-                                          (unsigned long)reg_info->flags);
-
-        vdev->bars[i].region.vbasedev = vbasedev;
-        vdev->bars[i].region.flags = reg_info->flags;
-        vdev->bars[i].region.size = reg_info->size;
-        vdev->bars[i].region.fd_offset = reg_info->offset;
-        vdev->bars[i].region.nr = i;
         QLIST_INIT(&vdev->bars[i].quirks);
-
-        g_free(reg_info);
     }
 
     ret = vfio_get_region_info(vbasedev,
@@ -2153,11 +2166,8 @@ error:
 static void vfio_put_device(VFIOPCIDevice *vdev)
 {
     g_free(vdev->vbasedev.name);
-    if (vdev->msix) {
-        object_unparent(OBJECT(&vdev->msix->mmap_mem));
-        g_free(vdev->msix);
-        vdev->msix = NULL;
-    }
+    g_free(vdev->msix);
+
     vfio_put_base_device(&vdev->vbasedev);
 }
 
diff --git a/hw/vfio/platform.c b/hw/vfio/platform.c
index f9b9c207ee..a2ab75d3f2 100644
--- a/hw/vfio/platform.c
+++ b/hw/vfio/platform.c
@@ -143,12 +143,8 @@ static void vfio_mmap_set_enabled(VFIOPlatformDevice *vdev, bool enabled)
 {
     int i;
 
-    trace_vfio_platform_mmap_set_enabled(enabled);
-
     for (i = 0; i < vdev->vbasedev.num_regions; i++) {
-        VFIORegion *region = vdev->regions[i];
-
-        memory_region_set_enabled(&region->mmap_mem, enabled);
+        vfio_region_mmaps_set_enabled(vdev->regions[i], enabled);
     }
 }
 
@@ -476,29 +472,16 @@ static int vfio_populate_device(VFIODevice *vbasedev)
     vdev->regions = g_new0(VFIORegion *, vbasedev->num_regions);
 
     for (i = 0; i < vbasedev->num_regions; i++) {
-        struct vfio_region_info *reg_info;
-        VFIORegion *ptr;
+        char *name = g_strdup_printf("VFIO %s region %d\n", vbasedev->name, i);
 
         vdev->regions[i] = g_new0(VFIORegion, 1);
-        ptr = vdev->regions[i];
-        ret = vfio_get_region_info(vbasedev, i, &reg_info);
+        ret = vfio_region_setup(OBJECT(vdev), vbasedev,
+                                vdev->regions[i], i, name);
+        g_free(name);
         if (ret) {
             error_report("vfio: Error getting region %d info: %m", i);
             goto reg_error;
         }
-        ptr->flags = reg_info->flags;
-        ptr->size = reg_info->size;
-        ptr->fd_offset = reg_info->offset;
-        ptr->nr = i;
-        ptr->vbasedev = vbasedev;
-
-        g_free(reg_info);
-
-        trace_vfio_platform_populate_regions(ptr->nr,
-                            (unsigned long)ptr->flags,
-                            (unsigned long)ptr->size,
-                            ptr->vbasedev->fd,
-                            (unsigned long)ptr->fd_offset);
     }
 
     vdev->mmap_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL,
@@ -535,6 +518,9 @@ irq_err:
     }
 reg_error:
     for (i = 0; i < vbasedev->num_regions; i++) {
+        if (vdev->regions[i]) {
+            vfio_region_finalize(vdev->regions[i]);
+        }
         g_free(vdev->regions[i]);
     }
     g_free(vdev->regions);
@@ -636,41 +622,6 @@ static int vfio_base_device_init(VFIODevice *vbasedev)
 }
 
 /**
- * vfio_map_region - initialize the 2 memory regions for a given
- * MMIO region index
- * @vdev: the VFIO platform device handle
- * @nr: the index of the region
- *
- * Init the top memory region and the mmapped memory region beneath
- * VFIOPlatformDevice is used since VFIODevice is not a QOM Object
- * and could not be passed to memory region functions
-*/
-static void vfio_map_region(VFIOPlatformDevice *vdev, int nr)
-{
-    VFIORegion *region = vdev->regions[nr];
-    uint64_t size = region->size;
-    char name[64];
-
-    if (!size) {
-        return;
-    }
-
-    g_snprintf(name, sizeof(name), "VFIO %s region %d",
-               vdev->vbasedev.name, nr);
-
-    /* A "slow" read/write mapping underlies all regions */
-    memory_region_init_io(&region->mem, OBJECT(vdev), &vfio_region_ops,
-                          region, name, size);
-
-    g_strlcat(name, " mmap", sizeof(name));
-
-    if (vfio_mmap_region(OBJECT(vdev), region, &region->mem,
-                         &region->mmap_mem, &region->mmap, size, 0, name)) {
-        error_report("%s unsupported. Performance may be slow", name);
-    }
-}
-
-/**
  * vfio_platform_realize  - the device realize function
  * @dev: device state pointer
  * @errp: error
@@ -700,8 +651,11 @@ static void vfio_platform_realize(DeviceState *dev, Error **errp)
     }
 
     for (i = 0; i < vbasedev->num_regions; i++) {
-        vfio_map_region(vdev, i);
-        sysbus_init_mmio(sbdev, &vdev->regions[i]->mem);
+        if (vfio_region_mmap(vdev->regions[i])) {
+            error_report("%s mmap unsupported. Performance may be slow",
+                         memory_region_name(vdev->regions[i]->mem));
+        }
+        sysbus_init_mmio(sbdev, vdev->regions[i]->mem);
     }
 }