Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/include/xen/events.h b/include/xen/events.h
index c0e6a05..3195230 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -14,11 +14,16 @@
 
 unsigned xen_evtchn_nr_channels(void);
 
-int bind_evtchn_to_irq(unsigned int evtchn);
-int bind_evtchn_to_irqhandler(unsigned int evtchn,
+int bind_evtchn_to_irq(evtchn_port_t evtchn);
+int bind_evtchn_to_irq_lateeoi(evtchn_port_t evtchn);
+int bind_evtchn_to_irqhandler(evtchn_port_t evtchn,
 			      irq_handler_t handler,
 			      unsigned long irqflags, const char *devname,
 			      void *dev_id);
+int bind_evtchn_to_irqhandler_lateeoi(evtchn_port_t evtchn,
+				      irq_handler_t handler,
+				      unsigned long irqflags, const char *devname,
+				      void *dev_id);
 int bind_virq_to_irq(unsigned int virq, unsigned int cpu, bool percpu);
 int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
 			    irq_handler_t handler,
@@ -31,13 +36,21 @@
 			   const char *devname,
 			   void *dev_id);
 int bind_interdomain_evtchn_to_irq(unsigned int remote_domain,
-				   unsigned int remote_port);
+				   evtchn_port_t remote_port);
+int bind_interdomain_evtchn_to_irq_lateeoi(unsigned int remote_domain,
+					   evtchn_port_t remote_port);
 int bind_interdomain_evtchn_to_irqhandler(unsigned int remote_domain,
-					  unsigned int remote_port,
+					  evtchn_port_t remote_port,
 					  irq_handler_t handler,
 					  unsigned long irqflags,
 					  const char *devname,
 					  void *dev_id);
+int bind_interdomain_evtchn_to_irqhandler_lateeoi(unsigned int remote_domain,
+						  evtchn_port_t remote_port,
+						  irq_handler_t handler,
+						  unsigned long irqflags,
+						  const char *devname,
+						  void *dev_id);
 
 /*
  * Common unbind function for all event sources. Takes IRQ to unbind from.
@@ -46,6 +59,14 @@
  */
 void unbind_from_irqhandler(unsigned int irq, void *dev_id);
 
+/*
+ * Send late EOI for an IRQ bound to an event channel via one of the *_lateeoi
+ * functions above.
+ */
+void xen_irq_lateeoi(unsigned int irq, unsigned int eoi_flags);
+/* Signal an event was spurious, i.e. there was no action resulting from it. */
+#define XEN_EOI_FLAG_SPURIOUS	0x00000001
+
 #define XEN_IRQ_PRIORITY_MAX     EVTCHN_FIFO_PRIORITY_MAX
 #define XEN_IRQ_PRIORITY_DEFAULT EVTCHN_FIFO_PRIORITY_DEFAULT
 #define XEN_IRQ_PRIORITY_MIN     EVTCHN_FIFO_PRIORITY_MIN
diff --git a/include/xen/grant_table.h b/include/xen/grant_table.h
index 9bc5bc0..a997835 100644
--- a/include/xen/grant_table.h
+++ b/include/xen/grant_table.h
@@ -157,6 +157,7 @@
 	map->flags = flags;
 	map->ref = ref;
 	map->dom = domid;
+	map->status = 1; /* arbitrary positive value */
 }
 
 static inline void
diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h
index 869c816..14d47ed 100644
--- a/include/xen/xenbus.h
+++ b/include/xen/xenbus.h
@@ -59,6 +59,15 @@
 	/* Path being watched. */
 	const char *node;
 
+	unsigned int nr_pending;
+
+	/*
+	 * Called just before enqueing new event while a spinlock is held.
+	 * The event will be discarded if this callback returns false.
+	 */
+	bool (*will_handle)(struct xenbus_watch *,
+			      const char *path, const char *token);
+
 	/* Callback (executed in a process context with no locks held). */
 	void (*callback)(struct xenbus_watch *,
 			 const char *path, const char *token);
@@ -178,8 +187,6 @@
 
 struct work_struct;
 
-void xenbus_probe(struct work_struct *);
-
 #define XENBUS_IS_ERR_READ(str) ({			\
 	if (!IS_ERR(str) && strlen(str) == 0) {		\
 		kfree(str);				\
@@ -192,10 +199,14 @@
 
 int xenbus_watch_path(struct xenbus_device *dev, const char *path,
 		      struct xenbus_watch *watch,
+		      bool (*will_handle)(struct xenbus_watch *,
+					  const char *, const char *),
 		      void (*callback)(struct xenbus_watch *,
 				       const char *, const char *));
-__printf(4, 5)
+__printf(5, 6)
 int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch,
+			 bool (*will_handle)(struct xenbus_watch *,
+					     const char *, const char *),
 			 void (*callback)(struct xenbus_watch *,
 					  const char *, const char *),
 			 const char *pathfmt, ...);