[RFC PATCH V3 21/26] vfio/pci: Replace backend specific calls with callbacks

[Reinette Chatre]

The backend specific code needed to manage the interrupts are
isolated into separate functions. With the backend specific
code isolated into functions, these functions
can be turned into callbacks for other backends to use.

Signed-off-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
---
Changes since RFC V2:
- New patch

 drivers/vfio/pci/vfio_pci_intrs.c | 17 +++++++++++------
 include/linux/vfio_pci_core.h     | 15 +++++++++++++++
 2 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/drivers/vfio/pci/vfio_pci_intrs.c b/drivers/vfio/pci/vfio_pci_intrs.c
index c1f65b8adfe2..1e6376b048de 100644
--- a/drivers/vfio/pci/vfio_pci_intrs.c
+++ b/drivers/vfio/pci/vfio_pci_intrs.c
@@ -490,7 +490,7 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_intr_ctx *intr_ctx,
 
 	if (ctx && ctx->trigger) {
 		irq_bypass_unregister_producer(&ctx->producer);
-		vfio_msi_free_interrupt(intr_ctx, ctx, vector);
+		intr_ctx->ops->msi_free_interrupt(intr_ctx, ctx, vector);
 		kfree(ctx->name);
 		ctx->name = NULL;
 		eventfd_ctx_put(ctx->trigger);
@@ -507,7 +507,7 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_intr_ctx *intr_ctx,
 			return -ENOMEM;
 	}
 
-	ctx->name = vfio_msi_device_name(intr_ctx, vector, index);
+	ctx->name = intr_ctx->ops->msi_device_name(intr_ctx, vector, index);
 	if (!ctx->name)
 		return -ENOMEM;
 
@@ -519,7 +519,7 @@ static int vfio_msi_set_vector_signal(struct vfio_pci_intr_ctx *intr_ctx,
 
 	ctx->trigger = trigger;
 
-	ret = vfio_msi_request_interrupt(intr_ctx, ctx, vector, index);
+	ret = intr_ctx->ops->msi_request_interrupt(intr_ctx, ctx, vector, index);
 	if (ret)
 		goto out_put_eventfd_ctx;
 
@@ -708,7 +708,7 @@ static int vfio_pci_set_msi_trigger(struct vfio_pci_intr_ctx *intr_ctx,
 	unsigned int i;
 
 	if (irq_is(intr_ctx, index) && !count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
-		vfio_msi_disable(intr_ctx, index);
+		intr_ctx->ops->msi_disable(intr_ctx, index);
 		return 0;
 	}
 
@@ -723,13 +723,13 @@ static int vfio_pci_set_msi_trigger(struct vfio_pci_intr_ctx *intr_ctx,
 			return vfio_msi_set_block(intr_ctx, start, count,
 						  fds, index);
 
-		ret = vfio_msi_enable(intr_ctx, start + count, index);
+		ret = intr_ctx->ops->msi_enable(intr_ctx, start + count, index);
 		if (ret)
 			return ret;
 
 		ret = vfio_msi_set_block(intr_ctx, start, count, fds, index);
 		if (ret)
-			vfio_msi_disable(intr_ctx, index);
+			intr_ctx->ops->msi_disable(intr_ctx, index);
 
 		return ret;
 	}
@@ -872,6 +872,11 @@ static struct vfio_pci_intr_ops vfio_pci_intr_ops = {
 	.set_msix_trigger = vfio_pci_set_msi_trigger,
 	.set_err_trigger = vfio_pci_set_err_trigger,
 	.set_req_trigger = vfio_pci_set_req_trigger,
+	.msi_enable = vfio_msi_enable,
+	.msi_disable = vfio_msi_disable,
+	.msi_request_interrupt = vfio_msi_request_interrupt,
+	.msi_free_interrupt = vfio_msi_free_interrupt,
+	.msi_device_name = vfio_msi_device_name,
 };
 
 void vfio_pci_init_intr_ctx(struct vfio_pci_core_device *vdev,
diff --git a/include/linux/vfio_pci_core.h b/include/linux/vfio_pci_core.h
index 8d2fb51a2dcc..f0951084a26f 100644
--- a/include/linux/vfio_pci_core.h
+++ b/include/linux/vfio_pci_core.h
@@ -69,6 +69,8 @@ struct vfio_pci_intr_ctx {
 	int				irq_type;
 };
 
+struct vfio_pci_irq_ctx;
+
 struct vfio_pci_intr_ops {
 	int (*set_intx_mask)(struct vfio_pci_intr_ctx *intr_ctx,
 			     unsigned int index, unsigned int start,
@@ -91,6 +93,19 @@ struct vfio_pci_intr_ops {
 	int (*set_req_trigger)(struct vfio_pci_intr_ctx *intr_ctx,
 			       unsigned int index, unsigned int start,
 			       unsigned int count, uint32_t flags, void *data);
+	int (*msi_enable)(struct vfio_pci_intr_ctx *intr_ctx, int nvec,
+			  unsigned int index);
+	void (*msi_disable)(struct vfio_pci_intr_ctx *intr_ctx,
+			    unsigned int index);
+	int (*msi_request_interrupt)(struct vfio_pci_intr_ctx *intr_ctx,
+				     struct vfio_pci_irq_ctx *ctx,
+				     unsigned int vector,
+				     unsigned int index);
+	void (*msi_free_interrupt)(struct vfio_pci_intr_ctx *intr_ctx,
+				   struct vfio_pci_irq_ctx *ctx,
+				   unsigned int vector);
+	char *(*msi_device_name)(struct vfio_pci_intr_ctx *intr_ctx,
+				 unsigned int vector, unsigned int index);
 };
 
 struct vfio_pci_core_device {
-- 
2.34.1