[Qemu-devel] [PATCH v9 06/12] vfio_pci: Update vfio_pci to use vfio_info_add_capability()

[Kirti Wankhede]

Update msix_sparse_mmap_cap() to use vfio_info_add_capability()
Update region type capability to use vfio_info_add_capability()
Can't split this commit for MSIx and region_type cap since there is a
common code which need to be updated for both the cases.

Signed-off-by: Kirti Wankhede <address@hidden>
Signed-off-by: Neo Jia <address@hidden>
Change-Id: I52bb28c7875a6da5a79ddad1843e6088aff58a45
---
 drivers/vfio/pci/vfio_pci.c | 72 +++++++++++++++++----------------------------
 1 file changed, 27 insertions(+), 45 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index d624a527777f..1ec0565b48ea 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -556,12 +556,12 @@ static int vfio_pci_for_each_slot_or_bus(struct pci_dev 
*pdev,
 }
 
 static int msix_sparse_mmap_cap(struct vfio_pci_device *vdev,
+                               struct vfio_region_info *info,
                                struct vfio_info_cap *caps)
 {
-       struct vfio_info_cap_header *header;
        struct vfio_region_info_cap_sparse_mmap *sparse;
        size_t end, size;
-       int nr_areas = 2, i = 0;
+       int nr_areas = 2, i = 0, ret;
 
        end = pci_resource_len(vdev->pdev, vdev->msix_bar);
 
@@ -572,13 +572,10 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device 
*vdev,
 
        size = sizeof(*sparse) + (nr_areas * sizeof(*sparse->areas));
 
-       header = vfio_info_cap_add(caps, size,
-                                  VFIO_REGION_INFO_CAP_SPARSE_MMAP, 1);
-       if (IS_ERR(header))
-               return PTR_ERR(header);
+       sparse = kzalloc(size, GFP_KERNEL);
+       if (!sparse)
+               return -ENOMEM;
 
-       sparse = container_of(header,
-                             struct vfio_region_info_cap_sparse_mmap, header);
        sparse->nr_areas = nr_areas;
 
        if (vdev->msix_offset & PAGE_MASK) {
@@ -594,26 +591,11 @@ static int msix_sparse_mmap_cap(struct vfio_pci_device 
*vdev,
                i++;
        }
 
-       return 0;
-}
-
-static int region_type_cap(struct vfio_pci_device *vdev,
-                          struct vfio_info_cap *caps,
-                          unsigned int type, unsigned int subtype)
-{
-       struct vfio_info_cap_header *header;
-       struct vfio_region_info_cap_type *cap;
-
-       header = vfio_info_cap_add(caps, sizeof(*cap),
-                                  VFIO_REGION_INFO_CAP_TYPE, 1);
-       if (IS_ERR(header))
-               return PTR_ERR(header);
+       ret = vfio_info_add_capability(info, caps,
+                                     VFIO_REGION_INFO_CAP_SPARSE_MMAP, sparse);
+       kfree(sparse);
 
-       cap = container_of(header, struct vfio_region_info_cap_type, header);
-       cap->type = type;
-       cap->subtype = subtype;
-
-       return 0;
+       return ret;
 }
 
 int vfio_pci_register_dev_region(struct vfio_pci_device *vdev,
@@ -704,7 +686,8 @@ static long vfio_pci_ioctl(void *device_data,
                        if (vdev->bar_mmap_supported[info.index]) {
                                info.flags |= VFIO_REGION_INFO_FLAG_MMAP;
                                if (info.index == vdev->msix_bar) {
-                                       ret = msix_sparse_mmap_cap(vdev, &caps);
+                                       ret = msix_sparse_mmap_cap(vdev, &info,
+                                                                  &caps);
                                        if (ret)
                                                return ret;
                                }
@@ -752,6 +735,9 @@ static long vfio_pci_ioctl(void *device_data,
 
                        break;
                default:
+               {
+                       struct vfio_region_info_cap_type cap_type;
+
                        if (info.index >=
                            VFIO_PCI_NUM_REGIONS + vdev->num_regions)
                                return -EINVAL;
@@ -762,27 +748,23 @@ static long vfio_pci_ioctl(void *device_data,
                        info.size = vdev->region[i].size;
                        info.flags = vdev->region[i].flags;
 
-                       ret = region_type_cap(vdev, &caps,
-                                             vdev->region[i].type,
-                                             vdev->region[i].subtype);
+                       cap_type.type = vdev->region[i].type;
+                       cap_type.subtype = vdev->region[i].subtype;
+
+                       ret = vfio_info_add_capability(&info, &caps,
+                                                     VFIO_REGION_INFO_CAP_TYPE,
+                                                     &cap_type);
                        if (ret)
                                return ret;
+
+               }
                }
 
-               if (caps.size) {
-                       info.flags |= VFIO_REGION_INFO_FLAG_CAPS;
-                       if (info.argsz < sizeof(info) + caps.size) {
-                               info.argsz = sizeof(info) + caps.size;
-                               info.cap_offset = 0;
-                       } else {
-                               vfio_info_cap_shift(&caps, sizeof(info));
-                               if (copy_to_user((void __user *)arg +
-                                                 sizeof(info), caps.buf,
-                                                 caps.size)) {
-                                       kfree(caps.buf);
-                                       return -EFAULT;
-                               }
-                               info.cap_offset = sizeof(info);
+               if (info.cap_offset) {
+                       if (copy_to_user((void __user *)arg + info.cap_offset,
+                                        caps.buf, caps.size)) {
+                               kfree(caps.buf);
+                               return -EFAULT;
                        }
 
                        kfree(caps.buf);
-- 
2.7.0