xen: Use evtchn_type_t as a type for event channels

Make event channel functions pass event channel port using
evtchn_port_t type. It eliminates signed <-> unsigned conversion.
Signed-off-by: Yan Yankovskyi <yyankovskyi@gmail.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Link: https://lore.kernel.org/r/20200323152343.GA28422@kbp1-lhp-F74019Signed-off-by: Juergen Gross <jgross@suse.com>

drivers/xen/events/events_2l.c

@@ -53,37 +53,37 @@ static void evtchn_2l_bind_to_cpu(struct irq_info *info, unsigned cpu)
 	set_bit(info->evtchn, BM(per_cpu(cpu_evtchn_mask, cpu)));
 }
 
-static void evtchn_2l_clear_pending(unsigned port)
+static void evtchn_2l_clear_pending(evtchn_port_t port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	sync_clear_bit(port, BM(&s->evtchn_pending[0]));
 }
 
-static void evtchn_2l_set_pending(unsigned port)
+static void evtchn_2l_set_pending(evtchn_port_t port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	sync_set_bit(port, BM(&s->evtchn_pending[0]));
 }
 
-static bool evtchn_2l_is_pending(unsigned port)
+static bool evtchn_2l_is_pending(evtchn_port_t port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	return sync_test_bit(port, BM(&s->evtchn_pending[0]));
 }
 
-static bool evtchn_2l_test_and_set_mask(unsigned port)
+static bool evtchn_2l_test_and_set_mask(evtchn_port_t port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	return sync_test_and_set_bit(port, BM(&s->evtchn_mask[0]));
 }
 
-static void evtchn_2l_mask(unsigned port)
+static void evtchn_2l_mask(evtchn_port_t port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	sync_set_bit(port, BM(&s->evtchn_mask[0]));
 }
 
-static void evtchn_2l_unmask(unsigned port)
+static void evtchn_2l_unmask(evtchn_port_t port)
 {
 	struct shared_info *s = HYPERVISOR_shared_info;
 	unsigned int cpu = get_cpu();
@@ -173,7 +173,7 @@ static void evtchn_2l_handle_events(unsigned cpu)
 	/* Timer interrupt has highest priority. */
 	irq = irq_from_virq(cpu, VIRQ_TIMER);
 	if (irq != -1) {
-		unsigned int evtchn = evtchn_from_irq(irq);
+		evtchn_port_t evtchn = evtchn_from_irq(irq);
 		word_idx = evtchn / BITS_PER_LONG;
 		bit_idx = evtchn % BITS_PER_LONG;
 		if (active_evtchns(cpu, s, word_idx) & (1ULL << bit_idx))
@@ -228,7 +228,7 @@ static void evtchn_2l_handle_events(unsigned cpu)
 
 		do {
 			xen_ulong_t bits;
-			int port;
+			evtchn_port_t port;
 
 			bits = MASK_LSBS(pending_bits, bit_idx);
 

drivers/xen/events/events_fifo.c

@@ -82,7 +82,7 @@ static unsigned event_array_pages __read_mostly;
 
 #endif
 
-static inline event_word_t *event_word_from_port(unsigned port)
+static inline event_word_t *event_word_from_port(evtchn_port_t port)
 {
 	unsigned i = port / EVENT_WORDS_PER_PAGE;
 
@@ -140,7 +140,7 @@ static void init_array_page(event_word_t *array_page)
 
 static int evtchn_fifo_setup(struct irq_info *info)
 {
-	unsigned port = info->evtchn;
+	evtchn_port_t port = info->evtchn;
 	unsigned new_array_pages;
 	int ret;
 
@@ -191,37 +191,37 @@ static void evtchn_fifo_bind_to_cpu(struct irq_info *info, unsigned cpu)
 	/* no-op */
 }
 
-static void evtchn_fifo_clear_pending(unsigned port)
+static void evtchn_fifo_clear_pending(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 	sync_clear_bit(EVTCHN_FIFO_BIT(PENDING, word), BM(word));
 }
 
-static void evtchn_fifo_set_pending(unsigned port)
+static void evtchn_fifo_set_pending(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 	sync_set_bit(EVTCHN_FIFO_BIT(PENDING, word), BM(word));
 }
 
-static bool evtchn_fifo_is_pending(unsigned port)
+static bool evtchn_fifo_is_pending(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 	return sync_test_bit(EVTCHN_FIFO_BIT(PENDING, word), BM(word));
 }
 
-static bool evtchn_fifo_test_and_set_mask(unsigned port)
+static bool evtchn_fifo_test_and_set_mask(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 	return sync_test_and_set_bit(EVTCHN_FIFO_BIT(MASKED, word), BM(word));
 }
 
-static void evtchn_fifo_mask(unsigned port)
+static void evtchn_fifo_mask(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 	sync_set_bit(EVTCHN_FIFO_BIT(MASKED, word), BM(word));
 }
 
-static bool evtchn_fifo_is_masked(unsigned port)
+static bool evtchn_fifo_is_masked(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 	return sync_test_bit(EVTCHN_FIFO_BIT(MASKED, word), BM(word));
@@ -242,7 +242,7 @@ static void clear_masked(volatile event_word_t *word)
 	} while (w != old);
 }
 
-static void evtchn_fifo_unmask(unsigned port)
+static void evtchn_fifo_unmask(evtchn_port_t port)
 {
 	event_word_t *word = event_word_from_port(port);
 
@@ -270,7 +270,7 @@ static uint32_t clear_linked(volatile event_word_t *word)
 	return w & EVTCHN_FIFO_LINK_MASK;
 }
 
-static void handle_irq_for_port(unsigned port)
+static void handle_irq_for_port(evtchn_port_t port)
 {
 	int irq;
 
@@ -286,7 +286,7 @@ static void consume_one_event(unsigned cpu,
 {
 	struct evtchn_fifo_queue *q = &per_cpu(cpu_queue, cpu);
 	uint32_t head;
-	unsigned port;
+	evtchn_port_t port;
 	event_word_t *word;
 
 	head = q->head[priority];

drivers/xen/events/events_internal.h

@@ -33,7 +33,7 @@ struct irq_info {
 	int refcnt;
 	enum xen_irq_type type;	/* type */
 	unsigned irq;
-	unsigned int evtchn;	/* event channel */
+	evtchn_port_t evtchn;	/* event channel */
 	unsigned short cpu;	/* cpu bound */
 
 	union {
@@ -60,12 +60,12 @@ struct evtchn_ops {
 	int (*setup)(struct irq_info *info);
 	void (*bind_to_cpu)(struct irq_info *info, unsigned cpu);
 
-	void (*clear_pending)(unsigned port);
-	void (*set_pending)(unsigned port);
-	bool (*is_pending)(unsigned port);
-	bool (*test_and_set_mask)(unsigned port);
-	void (*mask)(unsigned port);
-	void (*unmask)(unsigned port);
+	void (*clear_pending)(evtchn_port_t port);
+	void (*set_pending)(evtchn_port_t port);
+	bool (*is_pending)(evtchn_port_t port);
+	bool (*test_and_set_mask)(evtchn_port_t port);
+	void (*mask)(evtchn_port_t port);
+	void (*unmask)(evtchn_port_t port);
 
 	void (*handle_events)(unsigned cpu);
 	void (*resume)(void);
@@ -74,11 +74,11 @@ struct evtchn_ops {
 extern const struct evtchn_ops *evtchn_ops;
 
 extern int **evtchn_to_irq;
-int get_evtchn_to_irq(unsigned int evtchn);
+int get_evtchn_to_irq(evtchn_port_t evtchn);
 
 struct irq_info *info_for_irq(unsigned irq);
 unsigned cpu_from_irq(unsigned irq);
-unsigned cpu_from_evtchn(unsigned int evtchn);
+unsigned int cpu_from_evtchn(evtchn_port_t evtchn);
 
 static inline unsigned xen_evtchn_max_channels(void)
 {
@@ -102,32 +102,32 @@ static inline void xen_evtchn_port_bind_to_cpu(struct irq_info *info,
 	evtchn_ops->bind_to_cpu(info, cpu);
 }
 
-static inline void clear_evtchn(unsigned port)
+static inline void clear_evtchn(evtchn_port_t port)
 {
 	evtchn_ops->clear_pending(port);
 }
 
-static inline void set_evtchn(unsigned port)
+static inline void set_evtchn(evtchn_port_t port)
 {
 	evtchn_ops->set_pending(port);
 }
 
-static inline bool test_evtchn(unsigned port)
+static inline bool test_evtchn(evtchn_port_t port)
 {
 	return evtchn_ops->is_pending(port);
 }
 
-static inline bool test_and_set_mask(unsigned port)
+static inline bool test_and_set_mask(evtchn_port_t port)
 {
 	return evtchn_ops->test_and_set_mask(port);
 }
 
-static inline void mask_evtchn(unsigned port)
+static inline void mask_evtchn(evtchn_port_t port)
 {
 	return evtchn_ops->mask(port);
 }
 
-static inline void unmask_evtchn(unsigned port)
+static inline void unmask_evtchn(evtchn_port_t port)
 {
 	return evtchn_ops->unmask(port);
 }

drivers/xen/evtchn.c

@@ -83,7 +83,7 @@ struct per_user_data {
 struct user_evtchn {
 	struct rb_node node;
 	struct per_user_data *user;
-	unsigned port;
+	evtchn_port_t port;
 	bool enabled;
 };
 
@@ -138,7 +138,8 @@ static void del_evtchn(struct per_user_data *u, struct user_evtchn *evtchn)
 	kfree(evtchn);
 }
 
-static struct user_evtchn *find_evtchn(struct per_user_data *u, unsigned port)
+static struct user_evtchn *find_evtchn(struct per_user_data *u,
+				       evtchn_port_t port)
 {
 	struct rb_node *node = u->evtchns.rb_node;
 
@@ -163,7 +164,7 @@ static irqreturn_t evtchn_interrupt(int irq, void *data)
 	struct per_user_data *u = evtchn->user;
 
 	WARN(!evtchn->enabled,
-	     "Interrupt for port %d, but apparently not enabled; per-user %p\n",
+	     "Interrupt for port %u, but apparently not enabled; per-user %p\n",
 	     evtchn->port, u);
 
 	disable_irq_nosync(irq);
@@ -286,7 +287,7 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf,
 	mutex_lock(&u->bind_mutex);
 
 	for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) {
-		unsigned port = kbuf[i];
+		evtchn_port_t port = kbuf[i];
 		struct user_evtchn *evtchn;
 
 		evtchn = find_evtchn(u, port);
@@ -361,7 +362,7 @@ static int evtchn_resize_ring(struct per_user_data *u)
 	return 0;
 }
 
-static int evtchn_bind_to_user(struct per_user_data *u, int port)
+static int evtchn_bind_to_user(struct per_user_data *u, evtchn_port_t port)
 {
 	struct user_evtchn *evtchn;
 	struct evtchn_close close;
@@ -423,7 +424,7 @@ static void evtchn_unbind_from_user(struct per_user_data *u,
 
 static DEFINE_PER_CPU(int, bind_last_selected_cpu);
 
-static void evtchn_bind_interdom_next_vcpu(int evtchn)
+static void evtchn_bind_interdom_next_vcpu(evtchn_port_t evtchn)
 {
 	unsigned int selected_cpu, irq;
 	struct irq_desc *desc;

drivers/xen/gntdev-common.h

@@ -15,6 +15,7 @@
 #include <linux/mman.h>
 #include <linux/mmu_notifier.h>
 #include <linux/types.h>
+#include <xen/interface/event_channel.h>
 
 struct gntdev_dmabuf_priv;
 
@@ -38,7 +39,7 @@ struct gntdev_unmap_notify {
 	int flags;
 	/* Address relative to the start of the gntdev_grant_map. */
 	int addr;
-	int event;
+	evtchn_port_t event;
 };
 
 struct gntdev_grant_map {

drivers/xen/gntdev.c

@@ -652,7 +652,7 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
 	struct gntdev_grant_map *map;
 	int rc;
 	int out_flags;
-	unsigned int out_event;
+	evtchn_port_t out_event;
 
 	if (copy_from_user(&op, u, sizeof(op)))
 		return -EFAULT;

drivers/xen/pvcalls-back.c

@@ -300,7 +300,7 @@ static struct sock_mapping *pvcalls_new_active_socket(
 		struct pvcalls_fedata *fedata,
 		uint64_t id,
 		grant_ref_t ref,
-		uint32_t evtchn,
+		evtchn_port_t evtchn,
 		struct socket *sock)
 {
 	int ret;
@@ -905,7 +905,8 @@ static irqreturn_t pvcalls_back_conn_event(int irq, void *sock_map)
 
 static int backend_connect(struct xenbus_device *dev)
 {
-	int err, evtchn;
+	int err;
+	evtchn_port_t evtchn;
 	grant_ref_t ring_ref;
 	struct pvcalls_fedata *fedata = NULL;
 

drivers/xen/pvcalls-front.c

@@ -368,12 +368,12 @@ static int alloc_active_ring(struct sock_mapping *map)
 	return -ENOMEM;
 }
 
-static int create_active(struct sock_mapping *map, int *evtchn)
+static int create_active(struct sock_mapping *map, evtchn_port_t *evtchn)
 {
 	void *bytes;
 	int ret = -ENOMEM, irq = -1, i;
 
-	*evtchn = -1;
+	*evtchn = 0;
 	init_waitqueue_head(&map->active.inflight_conn_req);
 
 	bytes = map->active.data.in;
@@ -404,7 +404,7 @@ static int create_active(struct sock_mapping *map, int *evtchn)
 	return 0;
 
 out_error:
-	if (*evtchn >= 0)
+	if (*evtchn > 0)
 		xenbus_free_evtchn(pvcalls_front_dev, *evtchn);
 	return ret;
 }
@@ -415,7 +415,8 @@ int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr,
 	struct pvcalls_bedata *bedata;
 	struct sock_mapping *map = NULL;
 	struct xen_pvcalls_request *req;
-	int notify, req_id, ret, evtchn;
+	int notify, req_id, ret;
+	evtchn_port_t evtchn;
 
 	if (addr->sa_family != AF_INET || sock->type != SOCK_STREAM)
 		return -EOPNOTSUPP;
@@ -765,7 +766,8 @@ int pvcalls_front_accept(struct socket *sock, struct socket *newsock, int flags)
 	struct sock_mapping *map;
 	struct sock_mapping *map2 = NULL;
 	struct xen_pvcalls_request *req;
-	int notify, req_id, ret, evtchn, nonblock;
+	int notify, req_id, ret, nonblock;
+	evtchn_port_t evtchn;
 
 	map = pvcalls_enter_sock(sock);
 	if (IS_ERR(map))
@@ -1125,7 +1127,8 @@ static int pvcalls_front_remove(struct xenbus_device *dev)
 static int pvcalls_front_probe(struct xenbus_device *dev,
 			  const struct xenbus_device_id *id)
 {
-	int ret = -ENOMEM, evtchn, i;
+	int ret = -ENOMEM, i;
+	evtchn_port_t evtchn;
 	unsigned int max_page_order, function_calls, len;
 	char *versions;
 	grant_ref_t gref_head = 0;

drivers/xen/xen-pciback/xenbus.c

@@ -105,13 +105,13 @@ static void free_pdev(struct xen_pcibk_device *pdev)
 }
 
 static int xen_pcibk_do_attach(struct xen_pcibk_device *pdev, int gnt_ref,
-			     int remote_evtchn)
+			     evtchn_port_t remote_evtchn)
 {
 	int err = 0;
 	void *vaddr;
 
 	dev_dbg(&pdev->xdev->dev,
-		"Attaching to frontend resources - gnt_ref=%d evtchn=%d\n",
+		"Attaching to frontend resources - gnt_ref=%d evtchn=%u\n",
 		gnt_ref, remote_evtchn);
 
 	err = xenbus_map_ring_valloc(pdev->xdev, &gnt_ref, 1, &vaddr);
@@ -142,7 +142,8 @@ static int xen_pcibk_do_attach(struct xen_pcibk_device *pdev, int gnt_ref,
 static int xen_pcibk_attach(struct xen_pcibk_device *pdev)
 {
 	int err = 0;
-	int gnt_ref, remote_evtchn;
+	int gnt_ref;
+	evtchn_port_t remote_evtchn;
 	char *magic = NULL;
 
 

drivers/xen/xen-scsiback.c

@@ -854,7 +854,8 @@ static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref,
 static int scsiback_map(struct vscsibk_info *info)
 {
 	struct xenbus_device *dev = info->dev;
-	unsigned int ring_ref, evtchn;
+	unsigned int ring_ref;
+	evtchn_port_t evtchn;
 	int err;
 
 	err = xenbus_gather(XBT_NIL, dev->otherend,

drivers/xen/xenbus/xenbus_client.c

@@ -391,7 +391,7 @@ EXPORT_SYMBOL_GPL(xenbus_grant_ring);
  * error, the device will switch to XenbusStateClosing, and the error will be
  * saved in the store.
  */
-int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port)
+int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port)
 {
 	struct evtchn_alloc_unbound alloc_unbound;
 	int err;
@@ -414,7 +414,7 @@ EXPORT_SYMBOL_GPL(xenbus_alloc_evtchn);
 /**
  * Free an existing event channel. Returns 0 on success or -errno on error.
  */
-int xenbus_free_evtchn(struct xenbus_device *dev, int port)
+int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t port)
 {
 	struct evtchn_close close;
 	int err;
@@ -423,7 +423,7 @@ int xenbus_free_evtchn(struct xenbus_device *dev, int port)
 
 	err = HYPERVISOR_event_channel_op(EVTCHNOP_close, &close);
 	if (err)
-		xenbus_dev_error(dev, err, "freeing event channel %d", port);
+		xenbus_dev_error(dev, err, "freeing event channel %u", port);
 
 	return err;
 }

include/xen/events.h

@@ -14,8 +14,8 @@
 
 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_irqhandler(evtchn_port_t evtchn,
 			      irq_handler_t handler,
 			      unsigned long irqflags, const char *devname,
 			      void *dev_id);
@@ -31,9 +31,9 @@ int bind_ipi_to_irqhandler(enum ipi_vector ipi,
 			   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_irqhandler(unsigned int remote_domain,
-					  unsigned int remote_port,
+					  evtchn_port_t remote_port,
 					  irq_handler_t handler,
 					  unsigned long irqflags,
 					  const char *devname,
@@ -54,15 +54,15 @@ int xen_set_irq_priority(unsigned irq, unsigned priority);
 /*
  * Allow extra references to event channels exposed to userspace by evtchn
  */
-int evtchn_make_refcounted(unsigned int evtchn);
-int evtchn_get(unsigned int evtchn);
-void evtchn_put(unsigned int evtchn);
+int evtchn_make_refcounted(evtchn_port_t evtchn);
+int evtchn_get(evtchn_port_t evtchn);
+void evtchn_put(evtchn_port_t evtchn);
 
 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector);
-void rebind_evtchn_irq(int evtchn, int irq);
+void rebind_evtchn_irq(evtchn_port_t evtchn, int irq);
 int xen_set_affinity_evtchn(struct irq_desc *desc, unsigned int tcpu);
 
-static inline void notify_remote_via_evtchn(int port)
+static inline void notify_remote_via_evtchn(evtchn_port_t port)
 {
 	struct evtchn_send send = { .port = port };
 	(void)HYPERVISOR_event_channel_op(EVTCHNOP_send, &send);
@@ -86,9 +86,9 @@ void xen_poll_irq(int irq);
 void xen_poll_irq_timeout(int irq, u64 timeout);
 
 /* Determine the IRQ which is bound to an event channel */
-unsigned irq_from_evtchn(unsigned int evtchn);
+unsigned int irq_from_evtchn(evtchn_port_t evtchn);
 int irq_from_virq(unsigned int cpu, unsigned int virq);
-unsigned int evtchn_from_irq(unsigned irq);
+evtchn_port_t evtchn_from_irq(unsigned irq);
 
 #ifdef CONFIG_XEN_PVHVM
 /* Xen HVM evtchn vector callback */

include/xen/interface/event_channel.h

@@ -220,7 +220,7 @@ struct evtchn_expand_array {
 #define EVTCHNOP_set_priority    13
 struct evtchn_set_priority {
 	/* IN parameters. */
-	uint32_t port;
+	evtchn_port_t port;
 	uint32_t priority;
 };
 

include/xen/xenbus.h

@@ -47,6 +47,7 @@
 #include <xen/interface/grant_table.h>
 #include <xen/interface/io/xenbus.h>
 #include <xen/interface/io/xs_wire.h>
+#include <xen/interface/event_channel.h>
 
 #define XENBUS_MAX_RING_GRANT_ORDER 4
 #define XENBUS_MAX_RING_GRANTS      (1U << XENBUS_MAX_RING_GRANT_ORDER)
@@ -212,8 +213,8 @@ int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs,
 
 int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr);
 
-int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port);
-int xenbus_free_evtchn(struct xenbus_device *dev, int port);
+int xenbus_alloc_evtchn(struct xenbus_device *dev, evtchn_port_t *port);
+int xenbus_free_evtchn(struct xenbus_device *dev, evtchn_port_t port);
 
 enum xenbus_state xenbus_read_driver_state(const char *path);