vme: change bus error handling scheme

The current VME bus error handler adds errors to the bridge error list.
vme_master_{read,write} then traverses that list to look for relevant
errors.

Such scheme didn't work well for accesses going through vme_master_mmap
because they would also allocate a vme_bus_error, but have no way to do
vme_clear_errors call to free that memory.

This changes the error handling process to be other way around: now
vme_master_{read,write} defines a window in VME address space that will
catch possible errors.  VME bus error interrupt only traverses these
windows and marks those that had errors in them.

Signed-off-by: Dmitry Kalinkin <dmitry.kalinkin@gmail.com>
Cc: Igor Alekseev <igor.alekseev@itep.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 14 insertions, 9 deletions

diff --git a/drivers/vme/vme_bridge.h b/drivers/vme/vme_bridge.h
index 92fbe18cbc42..397578a73883 100644
--- a/drivers/vme/vme_bridge.h
+++ b/drivers/vme/vme_bridge.h
@@ -75,10 +75,13 @@ struct vme_lm_resource {
 	int monitors;
 };
 
-struct vme_bus_error {
+struct vme_error_handler {
 	struct list_head list;
-	u32 aspace;
-	unsigned long long address;
+	unsigned long long start;	/* Beginning of error window */
+	unsigned long long end;		/* End of error window */
+	unsigned long long first_error;	/* Address of the first error */
+	u32 aspace;			/* Address space of error window*/
+	unsigned num_errors;		/* Number of errors */
 };
 
 struct vme_callback {
@@ -106,8 +109,10 @@ struct vme_bridge {
 	struct list_head dma_resources;
 	struct list_head lm_resources;
 
-	struct list_head vme_errors;	/* List for errors generated on VME */
-	struct list_head devices;	/* List of devices on this bridge */
+	/* List for registered errors handlers */
+	struct list_head vme_error_handlers;
+	/* List of devices on this bridge */
+	struct list_head devices;
 
 	/* Bridge Info - XXX Move to private structure? */
 	struct device *parent;	/* Parent device (eg. pdev->dev for PCI) */
@@ -168,13 +173,13 @@ struct vme_bridge {
 
 void vme_bus_error_handler(struct vme_bridge *bridge,
 			   unsigned long long address, int am);
-struct vme_bus_error *vme_find_error(struct vme_bridge *bridge, u32 aspace,
-				     unsigned long long address, size_t count);
-void vme_clear_errors(struct vme_bridge *bridge, u32 aspace,
-		      unsigned long long address, size_t count);
 void vme_irq_handler(struct vme_bridge *, int, int);
 
 int vme_register_bridge(struct vme_bridge *);
 void vme_unregister_bridge(struct vme_bridge *);
+struct vme_error_handler *vme_register_error_handler(
+	struct vme_bridge *bridge, u32 aspace,
+	unsigned long long address, size_t len);
+void vme_unregister_error_handler(struct vme_error_handler *handler);
 
 #endif /* _VME_BRIDGE_H_ */