[RFC PATCH v2 2/7] util/vfio-helpers: Move IRQ 'type' from pci_init_irq() to open_pci()

[Philippe Mathieu-Daudé]

Once opened, we will used the same IRQ type for all our event
notifiers, so pass the argument when we open the PCI device,
store the IRQ type in the driver state, and directly use the
value saved in the state each time we call qemu_vfio_pci_init_irq.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 include/qemu/vfio-helpers.h |  5 +++--
 block/nvme.c                |  6 +++---
 util/vfio-helpers.c         | 13 +++++++++----
 3 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/include/qemu/vfio-helpers.h b/include/qemu/vfio-helpers.h
index 1f057c2b9e..728f40922b 100644
--- a/include/qemu/vfio-helpers.h
+++ b/include/qemu/vfio-helpers.h
@@ -15,7 +15,8 @@
 
 typedef struct QEMUVFIOState QEMUVFIOState;
 
-QEMUVFIOState *qemu_vfio_open_pci(const char *device, Error **errp);
+QEMUVFIOState *qemu_vfio_open_pci(const char *device, int irq_type,
+                                  Error **errp);
 void qemu_vfio_close(QEMUVFIOState *s);
 int qemu_vfio_dma_map(QEMUVFIOState *s, void *host, size_t size,
                       bool temporary, uint64_t *iova_list);
@@ -27,6 +28,6 @@ void *qemu_vfio_pci_map_bar(QEMUVFIOState *s, int index,
 void qemu_vfio_pci_unmap_bar(QEMUVFIOState *s, int index, void *bar,
                              uint64_t offset, uint64_t size);
 int qemu_vfio_pci_init_irq(QEMUVFIOState *s, EventNotifier *e,
-                           int irq_type, Error **errp);
+                           Error **errp);
 
 #endif
diff --git a/block/nvme.c b/block/nvme.c
index a61e86a83e..21b0770c02 100644
--- a/block/nvme.c
+++ b/block/nvme.c
@@ -711,7 +711,8 @@ static int nvme_init(BlockDriverState *bs, const char 
*device, int namespace,
         return ret;
     }
 
-    s->vfio = qemu_vfio_open_pci(device, errp);
+    s->vfio = qemu_vfio_open_pci(device, VFIO_PCI_MSIX_IRQ_INDEX,
+                                 errp);
     if (!s->vfio) {
         ret = -EINVAL;
         goto out;
@@ -784,8 +785,7 @@ static int nvme_init(BlockDriverState *bs, const char 
*device, int namespace,
         }
     }
 
-    ret = qemu_vfio_pci_init_irq(s->vfio, &s->irq_notifier,
-                                 VFIO_PCI_MSIX_IRQ_INDEX, errp);
+    ret = qemu_vfio_pci_init_irq(s->vfio, &s->irq_notifier, errp);
     if (ret) {
         goto out;
     }
diff --git a/util/vfio-helpers.c b/util/vfio-helpers.c
index 9cb9b553a5..f1196e43dc 100644
--- a/util/vfio-helpers.c
+++ b/util/vfio-helpers.c
@@ -43,6 +43,8 @@ typedef struct {
 struct QEMUVFIOState {
     QemuMutex lock;
 
+    int irq_type; /* vfio index */
+
     /* These fields are protected by BQL */
     int container;
     int group;
@@ -176,14 +178,14 @@ void qemu_vfio_pci_unmap_bar(QEMUVFIOState *s, int index, 
void *bar,
  * Initialize device IRQ with @irq_type and and register an event notifier.
  */
 int qemu_vfio_pci_init_irq(QEMUVFIOState *s, EventNotifier *e,
-                           int irq_type, Error **errp)
+                           Error **errp)
 {
     int r;
     struct vfio_irq_set *irq_set;
     size_t irq_set_size;
     struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info) };
 
-    irq_info.index = irq_type;
+    irq_info.index = s->irq_type;
     if (ioctl(s->device, VFIO_DEVICE_GET_IRQ_INFO, &irq_info)) {
         error_setg_errno(errp, errno, "Failed to get device interrupt info");
         return -errno;
@@ -237,6 +239,7 @@ static int qemu_vfio_pci_write_config(QEMUVFIOState *s, 
void *buf, int size, int
 }
 
 static int qemu_vfio_init_pci(QEMUVFIOState *s, const char *device,
+                              int irq_type,
                               Error **errp)
 {
     int ret;
@@ -331,6 +334,7 @@ static int qemu_vfio_init_pci(QEMUVFIOState *s, const char 
*device,
         ret = -errno;
         goto fail;
     }
+    s->irq_type = irq_type;
 
     if (device_info.num_regions < VFIO_PCI_CONFIG_REGION_INDEX) {
         error_setg(errp, "Invalid device regions");
@@ -423,12 +427,13 @@ static void qemu_vfio_open_common(QEMUVFIOState *s)
 /**
  * Open a PCI device, e.g. "0000:00:01.0".
  */
-QEMUVFIOState *qemu_vfio_open_pci(const char *device, Error **errp)
+QEMUVFIOState *qemu_vfio_open_pci(const char *device, int irq_type,
+                                  Error **errp)
 {
     int r;
     QEMUVFIOState *s = g_new0(QEMUVFIOState, 1);
 
-    r = qemu_vfio_init_pci(s, device, errp);
+    r = qemu_vfio_init_pci(s, device, irq_type, errp);
     if (r) {
         g_free(s);
         return NULL;
-- 
2.21.3