[RFC v8 16/28] vfio: Helper to get IRQ info including capabilities

[Eric Auger <eric.auger@redhat.com>]

As done for vfio regions, add helpers to retrieve irq info
including their optional capabilities.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 hw/vfio/common.c              | 97 +++++++++++++++++++++++++++++++++++
 hw/vfio/trace-events          |  1 +
 include/hw/vfio/vfio-common.h |  7 +++
 3 files changed, 105 insertions(+)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 8a64ba414b..9c8533c9c5 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1419,6 +1419,25 @@ bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
     return true;
 }
 
+struct vfio_info_cap_header *
+vfio_get_irq_info_cap(struct vfio_irq_info *info, uint16_t id)
+{
+    struct vfio_info_cap_header *hdr;
+    void *ptr = info;
+
+    if (!(info->flags & VFIO_IRQ_INFO_FLAG_CAPS)) {
+        return NULL;
+    }
+
+    for (hdr = ptr + info->cap_offset; hdr != ptr; hdr = ptr + hdr->next) {
+        if (hdr->id == id) {
+            return hdr;
+        }
+    }
+
+    return NULL;
+}
+
 static int vfio_setup_region_sparse_mmaps(VFIORegion *region,
                                           struct vfio_region_info *info)
 {
@@ -2352,6 +2371,33 @@ retry:
     return 0;
 }
 
+int vfio_get_irq_info(VFIODevice *vbasedev, int index,
+                      struct vfio_irq_info **info)
+{
+    size_t argsz = sizeof(struct vfio_irq_info);
+
+    *info = g_malloc0(argsz);
+
+    (*info)->index = index;
+retry:
+    (*info)->argsz = argsz;
+
+    if (ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, *info)) {
+        g_free(*info);
+        *info = NULL;
+        return -errno;
+    }
+
+    if ((*info)->argsz > argsz) {
+        argsz = (*info)->argsz;
+        *info = g_realloc(*info, argsz);
+
+        goto retry;
+    }
+
+    return 0;
+}
+
 int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
                              uint32_t subtype, struct vfio_region_info **info)
 {
@@ -2387,6 +2433,42 @@ int vfio_get_dev_region_info(VFIODevice *vbasedev, uint32_t type,
     return -ENODEV;
 }
 
+int vfio_get_dev_irq_info(VFIODevice *vbasedev, uint32_t type,
+                          uint32_t subtype, struct vfio_irq_info **info)
+{
+    int i;
+
+    for (i = 0; i < vbasedev->num_irqs; i++) {
+        struct vfio_info_cap_header *hdr;
+        struct vfio_irq_info_cap_type *cap_type;
+
+        if (vfio_get_irq_info(vbasedev, i, info)) {
+            continue;
+        }
+
+        hdr = vfio_get_irq_info_cap(*info, VFIO_IRQ_INFO_CAP_TYPE);
+        if (!hdr) {
+            g_free(*info);
+            continue;
+        }
+
+        cap_type = container_of(hdr, struct vfio_irq_info_cap_type, header);
+
+        trace_vfio_get_dev_irq(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;
+}
+
+
 bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
 {
     struct vfio_region_info *info = NULL;
@@ -2402,6 +2484,21 @@ bool vfio_has_region_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
     return ret;
 }
 
+bool vfio_has_irq_cap(VFIODevice *vbasedev, int region, uint16_t cap_type)
+{
+    struct vfio_region_info *info = NULL;
+    bool ret = false;
+
+    if (!vfio_get_region_info(vbasedev, region, &info)) {
+        if (vfio_get_region_info_cap(info, cap_type)) {
+            ret = true;
+        }
+        g_free(info);
+    }
+
+    return ret;
+}
+
 /*
  * Interfaces for IBM EEH (Enhanced Error Handling)
  */
diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
index 8e2a297a4c..815a71e099 100644
--- a/hw/vfio/trace-events
+++ b/hw/vfio/trace-events
@@ -119,6 +119,7 @@ vfio_region_unmap(const char *name, unsigned long offset, unsigned long end) "Re
 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, unsigned long start, unsigned long 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"
+vfio_get_dev_irq(const char *name, int index, uint32_t type, uint32_t subtype) "%s index %d, %08x/%0x8"
 vfio_dma_unmap_overflow_workaround(void) ""
 vfio_iommu_addr_inv_iotlb(int asid, uint64_t addr, uint64_t size, uint64_t nb_granules, bool leaf) "nested IOTLB invalidate asid=%d, addr=0x%"PRIx64" granule_size=0x%"PRIx64" nb_granules=0x%"PRIx64" leaf=%d"
 vfio_iommu_asid_inv_iotlb(int asid) "nested IOTLB invalidate asid=%d"
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index f30133b2a3..fcbda2d071 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -232,6 +232,13 @@ bool vfio_get_info_dma_avail(struct vfio_iommu_type1_info *info,
                              unsigned int *avail);
 struct vfio_info_cap_header *
 vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id);
+int vfio_get_irq_info(VFIODevice *vbasedev, int index,
+                      struct vfio_irq_info **info);
+int vfio_get_dev_irq_info(VFIODevice *vbasedev, uint32_t type,
+                          uint32_t subtype, struct vfio_irq_info **info);
+bool vfio_has_irq_cap(VFIODevice *vbasedev, int irq, uint16_t cap_type);
+struct vfio_info_cap_header *
+vfio_get_irq_info_cap(struct vfio_irq_info *info, uint16_t id);
 #endif
 extern const MemoryListener vfio_prereg_listener;
 
-- 
2.26.2