[Qemu-devel] [RFC PATCH v5 2/7] vfio: Create device specific region info helper

[Alex Williamson]

Given a device specific region type and sub-type, find it.  Also
cleanup return point on error in vfio_get_region_info() so that we
always return 0 with a valid pointer or -errno and NULL.

Signed-off-by: Alex Williamson <address@hidden>
---
 hw/vfio/common.c              |   36 ++++++++++++++++++++++++++++++++++++
 include/hw/vfio/vfio-common.h |    2 ++
 trace-events                  |    4 ++--
 3 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index eb6f04e..ae2c13b 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1142,6 +1142,7 @@ retry:
 
     if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_REGION_INFO, *info)) {
         g_free(*info);
+        *info = NULL;
         return -errno;
     }
 
@@ -1155,6 +1156,41 @@ retry:
     return 0;
 }
 
+int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
+                             uint32_t subtype, struct vfio_region_info **info)
+{
+    int i;
+
+    for (i = 0; i < vbasedev->num_regions; i++) {
+        struct vfio_info_cap_header *hdr;
+        struct vfio_region_info_cap_type *cap_type;
+
+        if (vfio_get_region_info(vbasedev, i, info)) {
+            continue;
+        }
+
+        hdr = vfio_get_region_info_cap(*info, VFIO_REGION_INFO_CAP_TYPE);
+        if (!hdr) {
+            g_free(*info);
+            continue;
+        }
+
+        cap_type = container_of(hdr, struct vfio_region_info_cap_type, header);
+
+        trace_vfio_get_dev_region(vbasedev->name, i,
+                                  cap_type->type, cap_type->subtype);
+
+        if (cap_type->type == type && cap_type->subtype == subtype) {
+            return 0;
+        }
+
+        g_free(*info);
+    }
+
+    *info = NULL;
+    return -ENODEV;
+}
+
 /*
  * Interfaces for IBM EEH (Enhanced Error Handling)
  */
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index eb0e1b0..a947f9c 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -154,5 +154,7 @@ extern QLIST_HEAD(vfio_as_head, VFIOAddressSpace) 
vfio_address_spaces;
 #ifdef CONFIG_LINUX
 int vfio_get_region_info(VFIODevice *vbasedev, int index,
                          struct vfio_region_info **info);
+int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
+                             uint32_t subtype, struct vfio_region_info **info);
 #endif
 #endif /* !HW_VFIO_VFIO_COMMON_H */
diff --git a/trace-events b/trace-events
index f1e1844..d099a2c 100644
--- a/trace-events
+++ b/trace-events
@@ -1715,8 +1715,7 @@ vfio_quirk_ati_bonaire_reset_timeout(const char *name) 
"%s"
 vfio_quirk_ati_bonaire_reset_done(const char *name) "%s"
 vfio_quirk_ati_bonaire_reset(const char *name) "%s"
 
-
-# hw/vfio/vfio-common.c
+# hw/vfio/common.c
 vfio_region_write(const char *name, int index, uint64_t addr, uint64_t data, 
unsigned size) " (%s:region%d+0x%"PRIx64", 0x%"PRIx64 ", %d)"
 vfio_region_read(char *name, int index, uint64_t addr, unsigned size, uint64_t 
data) " (%s:region%d+0x%"PRIx64", %d) = 0x%"PRIx64
 vfio_iommu_map_notify(uint64_t iova_start, uint64_t iova_end) "iommu map @ 
%"PRIx64" - %"PRIx64
@@ -1737,6 +1736,7 @@ vfio_region_finalize(const char *name, int index) "Device 
%s, region %d"
 vfio_region_mmaps_set_enabled(const char *name, bool enabled) "Region %s mmaps 
enabled: %d"
 vfio_region_sparse_mmap_header(const char *name, int index, int nr_areas) 
"Device %s region %d: %d sparse mmap entries"
 vfio_region_sparse_mmap_entry(int i, off_t start, off_t end) "sparse entry %d 
[0x%lx - 0x%lx]"
+vfio_get_dev_region(const char *name, int index, uint32_t type, uint32_t 
subtype) "%s index %d, %08x/%0x8"
 
 # hw/vfio/platform.c
 vfio_platform_base_device_init(char *name, int groupid) "%s belongs to group 
#%d"