commit 725ccd7e419d640ebee4c3869235efea070764de
author Avihai Horon <avihaih@nvidia.com> Tue Mar 07 12:54:39 2023 +0000
committer Alex Williamson <alex.williamson@redhat.com> Tue Mar 07 07:20:32 2023 -0700
tree 328839532edf51148dc11c5bf53ad59887539b18
parent 236e0a45f507f1e4130fce9c8edb615bf5e0b00e

vfio/common: Add VFIOBitmap and alloc function

There are already two places where dirty page bitmap allocation and
calculations are done in open code.

To avoid code duplication, introduce VFIOBitmap struct and corresponding
alloc function and use them where applicable.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-5-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

hw/vfio/common.c

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 4c80151..cec3de0 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -320,6 +320,25 @@
  * Device state interfaces
  */
 
+typedef struct {
+    unsigned long *bitmap;
+    hwaddr size;
+    hwaddr pages;
+} VFIOBitmap;
+
+static int vfio_bitmap_alloc(VFIOBitmap *vbmap, hwaddr size)
+{
+    vbmap->pages = REAL_HOST_PAGE_ALIGN(size) / qemu_real_host_page_size();
+    vbmap->size = ROUND_UP(vbmap->pages, sizeof(__u64) * BITS_PER_BYTE) /
+                                         BITS_PER_BYTE;
+    vbmap->bitmap = g_try_malloc0(vbmap->size);
+    if (!vbmap->bitmap) {
+        return -ENOMEM;
+    }
+
+    return 0;
+}
+
 bool vfio_mig_active(void)
 {
     VFIOGroup *group;
@@ -468,9 +487,14 @@
 {
     struct vfio_iommu_type1_dma_unmap *unmap;
     struct vfio_bitmap *bitmap;
-    uint64_t pages = REAL_HOST_PAGE_ALIGN(size) / qemu_real_host_page_size();
+    VFIOBitmap vbmap;
     int ret;
 
+    ret = vfio_bitmap_alloc(&vbmap, size);
+    if (ret) {
+        return ret;
+    }
+
     unmap = g_malloc0(sizeof(*unmap) + sizeof(*bitmap));
 
     unmap->argsz = sizeof(*unmap) + sizeof(*bitmap);
@@ -484,35 +508,28 @@
      * qemu_real_host_page_size to mark those dirty. Hence set bitmap_pgsize
      * to qemu_real_host_page_size.
      */
-
     bitmap->pgsize = qemu_real_host_page_size();
-    bitmap->size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) /
-                   BITS_PER_BYTE;
+    bitmap->size = vbmap.size;
+    bitmap->data = (__u64 *)vbmap.bitmap;
 
-    if (bitmap->size > container->max_dirty_bitmap_size) {
-        error_report("UNMAP: Size of bitmap too big 0x%"PRIx64,
-                     (uint64_t)bitmap->size);
+    if (vbmap.size > container->max_dirty_bitmap_size) {
+        error_report("UNMAP: Size of bitmap too big 0x%"PRIx64, vbmap.size);
         ret = -E2BIG;
         goto unmap_exit;
     }
 
-    bitmap->data = g_try_malloc0(bitmap->size);
-    if (!bitmap->data) {
-        ret = -ENOMEM;
-        goto unmap_exit;
-    }
-
     ret = ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, unmap);
     if (!ret) {
-        cpu_physical_memory_set_dirty_lebitmap((unsigned long *)bitmap->data,
-                iotlb->translated_addr, pages);
+        cpu_physical_memory_set_dirty_lebitmap(vbmap.bitmap,
+                iotlb->translated_addr, vbmap.pages);
     } else {
         error_report("VFIO_UNMAP_DMA with DIRTY_BITMAP : %m");
     }
 
-    g_free(bitmap->data);
 unmap_exit:
     g_free(unmap);
+    g_free(vbmap.bitmap);
+
     return ret;
 }
 
@@ -1329,7 +1346,7 @@
 {
     struct vfio_iommu_type1_dirty_bitmap *dbitmap;
     struct vfio_iommu_type1_dirty_bitmap_get *range;
-    uint64_t pages;
+    VFIOBitmap vbmap;
     int ret;
 
     if (!container->dirty_pages_supported) {
@@ -1339,6 +1356,11 @@
         return 0;
     }
 
+    ret = vfio_bitmap_alloc(&vbmap, size);
+    if (ret) {
+        return ret;
+    }
+
     dbitmap = g_malloc0(sizeof(*dbitmap) + sizeof(*range));
 
     dbitmap->argsz = sizeof(*dbitmap) + sizeof(*range);
@@ -1353,15 +1375,8 @@
      * to qemu_real_host_page_size.
      */
     range->bitmap.pgsize = qemu_real_host_page_size();
-
-    pages = REAL_HOST_PAGE_ALIGN(range->size) / qemu_real_host_page_size();
-    range->bitmap.size = ROUND_UP(pages, sizeof(__u64) * BITS_PER_BYTE) /
-                                         BITS_PER_BYTE;
-    range->bitmap.data = g_try_malloc0(range->bitmap.size);
-    if (!range->bitmap.data) {
-        ret = -ENOMEM;
-        goto err_out;
-    }
+    range->bitmap.size = vbmap.size;
+    range->bitmap.data = (__u64 *)vbmap.bitmap;
 
     ret = ioctl(container->fd, VFIO_IOMMU_DIRTY_PAGES, dbitmap);
     if (ret) {
@@ -1372,14 +1387,14 @@
         goto err_out;
     }
 
-    cpu_physical_memory_set_dirty_lebitmap((unsigned long *)range->bitmap.data,
-                                            ram_addr, pages);
+    cpu_physical_memory_set_dirty_lebitmap(vbmap.bitmap, ram_addr,
+                                           vbmap.pages);
 
     trace_vfio_get_dirty_bitmap(container->fd, range->iova, range->size,
                                 range->bitmap.size, ram_addr);
 err_out:
-    g_free(range->bitmap.data);
     g_free(dbitmap);
+    g_free(vbmap.bitmap);
 
     return ret;
 }