Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/misc/ocxl/afu_irq.c b/drivers/misc/ocxl/afu_irq.c
index e70cfa2..70f8f1c 100644
--- a/drivers/misc/ocxl/afu_irq.c
+++ b/drivers/misc/ocxl/afu_irq.c
@@ -1,7 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0+
 // Copyright 2017 IBM Corp.
 #include <linux/interrupt.h>
-#include <linux/eventfd.h>
 #include <asm/pnv-ocxl.h>
 #include "ocxl_internal.h"
 #include "trace.h"
@@ -12,27 +11,59 @@
 	unsigned int virq;
 	char *name;
 	u64 trigger_page;
-	struct eventfd_ctx *ev_ctx;
+	irqreturn_t (*handler)(void *private);
+	void (*free_private)(void *private);
+	void *private;
 };
 
-static int irq_offset_to_id(struct ocxl_context *ctx, u64 offset)
+int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset)
 {
 	return (offset - ctx->afu->irq_base_offset) >> PAGE_SHIFT;
 }
 
-static u64 irq_id_to_offset(struct ocxl_context *ctx, int id)
+u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id)
 {
-	return ctx->afu->irq_base_offset + (id << PAGE_SHIFT);
+	return ctx->afu->irq_base_offset + (irq_id << PAGE_SHIFT);
 }
 
+int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id,
+		irqreturn_t (*handler)(void *private),
+		void (*free_private)(void *private),
+		void *private)
+{
+	struct afu_irq *irq;
+	int rc;
+
+	mutex_lock(&ctx->irq_lock);
+	irq = idr_find(&ctx->irq_idr, irq_id);
+	if (!irq) {
+		rc = -EINVAL;
+		goto unlock;
+	}
+
+	irq->handler = handler;
+	irq->private = private;
+	irq->free_private = free_private;
+
+	rc = 0;
+	// Fall through to unlock
+
+unlock:
+	mutex_unlock(&ctx->irq_lock);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(ocxl_irq_set_handler);
+
 static irqreturn_t afu_irq_handler(int virq, void *data)
 {
 	struct afu_irq *irq = (struct afu_irq *) data;
 
 	trace_ocxl_afu_irq_receive(virq);
-	if (irq->ev_ctx)
-		eventfd_signal(irq->ev_ctx, 1);
-	return IRQ_HANDLED;
+
+	if (irq->handler)
+		return irq->handler(irq->private);
+
+	return IRQ_HANDLED; // Just drop it on the ground
 }
 
 static int setup_afu_irq(struct ocxl_context *ctx, struct afu_irq *irq)
@@ -70,7 +101,7 @@
 	kfree(irq->name);
 }
 
-int ocxl_afu_irq_alloc(struct ocxl_context *ctx, u64 *irq_offset)
+int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id)
 {
 	struct afu_irq *irq;
 	int rc;
@@ -102,11 +133,11 @@
 	if (rc)
 		goto err_alloc;
 
-	*irq_offset = irq_id_to_offset(ctx, irq->id);
-
-	trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq,
-				*irq_offset);
+	trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq);
 	mutex_unlock(&ctx->irq_lock);
+
+	*irq_id = irq->id;
+
 	return 0;
 
 err_alloc:
@@ -118,29 +149,29 @@
 	kfree(irq);
 	return rc;
 }
+EXPORT_SYMBOL_GPL(ocxl_afu_irq_alloc);
 
 static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx)
 {
 	trace_ocxl_afu_irq_free(ctx->pasid, irq->id);
 	if (ctx->mapping)
 		unmap_mapping_range(ctx->mapping,
-				irq_id_to_offset(ctx, irq->id),
+				ocxl_irq_id_to_offset(ctx, irq->id),
 				1 << PAGE_SHIFT, 1);
 	release_afu_irq(irq);
-	if (irq->ev_ctx)
-		eventfd_ctx_put(irq->ev_ctx);
+	if (irq->free_private)
+		irq->free_private(irq->private);
 	ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq);
 	kfree(irq);
 }
 
-int ocxl_afu_irq_free(struct ocxl_context *ctx, u64 irq_offset)
+int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id)
 {
 	struct afu_irq *irq;
-	int id = irq_offset_to_id(ctx, irq_offset);
 
 	mutex_lock(&ctx->irq_lock);
 
-	irq = idr_find(&ctx->irq_idr, id);
+	irq = idr_find(&ctx->irq_idr, irq_id);
 	if (!irq) {
 		mutex_unlock(&ctx->irq_lock);
 		return -EINVAL;
@@ -150,6 +181,7 @@
 	mutex_unlock(&ctx->irq_lock);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(ocxl_afu_irq_free);
 
 void ocxl_afu_irq_free_all(struct ocxl_context *ctx)
 {
@@ -162,41 +194,16 @@
 	mutex_unlock(&ctx->irq_lock);
 }
 
-int ocxl_afu_irq_set_fd(struct ocxl_context *ctx, u64 irq_offset, int eventfd)
+u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id)
 {
 	struct afu_irq *irq;
-	struct eventfd_ctx *ev_ctx;
-	int rc = 0, id = irq_offset_to_id(ctx, irq_offset);
-
-	mutex_lock(&ctx->irq_lock);
-	irq = idr_find(&ctx->irq_idr, id);
-	if (!irq) {
-		rc = -EINVAL;
-		goto unlock;
-	}
-
-	ev_ctx = eventfd_ctx_fdget(eventfd);
-	if (IS_ERR(ev_ctx)) {
-		rc = -EINVAL;
-		goto unlock;
-	}
-
-	irq->ev_ctx = ev_ctx;
-unlock:
-	mutex_unlock(&ctx->irq_lock);
-	return rc;
-}
-
-u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, u64 irq_offset)
-{
-	struct afu_irq *irq;
-	int id = irq_offset_to_id(ctx, irq_offset);
 	u64 addr = 0;
 
 	mutex_lock(&ctx->irq_lock);
-	irq = idr_find(&ctx->irq_idr, id);
+	irq = idr_find(&ctx->irq_idr, irq_id);
 	if (irq)
 		addr = irq->trigger_page;
 	mutex_unlock(&ctx->irq_lock);
 	return addr;
 }
+EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr);