v4.19.13 snapshot.
diff --git a/drivers/s390/cio/css.h b/drivers/s390/cio/css.h
new file mode 100644
index 0000000..8d83290
--- /dev/null
+++ b/drivers/s390/cio/css.h
@@ -0,0 +1,157 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _CSS_H
+#define _CSS_H
+
+#include <linux/mutex.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include <linux/device.h>
+#include <linux/types.h>
+
+#include <asm/cio.h>
+#include <asm/chpid.h>
+#include <asm/schid.h>
+
+#include "cio.h"
+
+/*
+ * path grouping stuff
+ */
+#define SPID_FUNC_SINGLE_PATH 0x00
+#define SPID_FUNC_MULTI_PATH 0x80
+#define SPID_FUNC_ESTABLISH 0x00
+#define SPID_FUNC_RESIGN 0x40
+#define SPID_FUNC_DISBAND 0x20
+
+#define SNID_STATE1_RESET 0
+#define SNID_STATE1_UNGROUPED 2
+#define SNID_STATE1_GROUPED 3
+
+#define SNID_STATE2_NOT_RESVD 0
+#define SNID_STATE2_RESVD_ELSE 2
+#define SNID_STATE2_RESVD_SELF 3
+
+#define SNID_STATE3_MULTI_PATH 1
+#define SNID_STATE3_SINGLE_PATH 0
+
+struct path_state {
+ __u8 state1 : 2; /* path state value 1 */
+ __u8 state2 : 2; /* path state value 2 */
+ __u8 state3 : 1; /* path state value 3 */
+ __u8 resvd : 3; /* reserved */
+} __attribute__ ((packed));
+
+struct extended_cssid {
+ u8 version;
+ u8 cssid;
+} __attribute__ ((packed));
+
+struct pgid {
+ union {
+ __u8 fc; /* SPID function code */
+ struct path_state ps; /* SNID path state */
+ } __attribute__ ((packed)) inf;
+ union {
+ __u32 cpu_addr : 16; /* CPU address */
+ struct extended_cssid ext_cssid;
+ } __attribute__ ((packed)) pgid_high;
+ __u32 cpu_id : 24; /* CPU identification */
+ __u32 cpu_model : 16; /* CPU model */
+ __u32 tod_high; /* high word TOD clock */
+} __attribute__ ((packed));
+
+struct subchannel;
+struct chp_link;
+/**
+ * struct css_driver - device driver for subchannels
+ * @subchannel_type: subchannel type supported by this driver
+ * @drv: embedded device driver structure
+ * @irq: called on interrupts
+ * @chp_event: called for events affecting a channel path
+ * @sch_event: called for events affecting the subchannel
+ * @probe: function called on probe
+ * @remove: function called on remove
+ * @shutdown: called at device shutdown
+ * @prepare: prepare for pm state transition
+ * @complete: undo work done in @prepare
+ * @freeze: callback for freezing during hibernation snapshotting
+ * @thaw: undo work done in @freeze
+ * @restore: callback for restoring after hibernation
+ * @settle: wait for asynchronous work to finish
+ */
+struct css_driver {
+ struct css_device_id *subchannel_type;
+ struct device_driver drv;
+ void (*irq)(struct subchannel *);
+ int (*chp_event)(struct subchannel *, struct chp_link *, int);
+ int (*sch_event)(struct subchannel *, int);
+ int (*probe)(struct subchannel *);
+ int (*remove)(struct subchannel *);
+ void (*shutdown)(struct subchannel *);
+ int (*prepare) (struct subchannel *);
+ void (*complete) (struct subchannel *);
+ int (*freeze)(struct subchannel *);
+ int (*thaw) (struct subchannel *);
+ int (*restore)(struct subchannel *);
+ int (*settle)(void);
+};
+
+#define to_cssdriver(n) container_of(n, struct css_driver, drv)
+
+extern int css_driver_register(struct css_driver *);
+extern void css_driver_unregister(struct css_driver *);
+
+extern void css_sch_device_unregister(struct subchannel *);
+extern int css_register_subchannel(struct subchannel *);
+extern struct subchannel *css_alloc_subchannel(struct subchannel_id,
+ struct schib *schib);
+extern struct subchannel *get_subchannel_by_schid(struct subchannel_id);
+extern int css_init_done;
+extern int max_ssid;
+int for_each_subchannel_staged(int (*fn_known)(struct subchannel *, void *),
+ int (*fn_unknown)(struct subchannel_id,
+ void *), void *data);
+extern int for_each_subchannel(int(*fn)(struct subchannel_id, void *), void *);
+void css_update_ssd_info(struct subchannel *sch);
+
+struct channel_subsystem {
+ int cssid;
+ struct channel_path *chps[__MAX_CHPID + 1];
+ struct device device;
+ struct pgid global_pgid;
+ struct mutex mutex;
+ /* channel measurement related */
+ int cm_enabled;
+ void *cub_addr1;
+ void *cub_addr2;
+ /* for orphaned ccw devices */
+ struct subchannel *pseudo_subchannel;
+};
+#define to_css(dev) container_of(dev, struct channel_subsystem, device)
+
+extern struct channel_subsystem *channel_subsystems[];
+
+/* Dummy helper which needs to change once we support more than one css. */
+static inline struct channel_subsystem *css_by_id(u8 cssid)
+{
+ return channel_subsystems[0];
+}
+
+/* Dummy iterator which needs to change once we support more than one css. */
+#define for_each_css(css) \
+ for ((css) = channel_subsystems[0]; (css); (css) = NULL)
+
+/* Helper functions to build lists for the slow path. */
+void css_schedule_eval(struct subchannel_id schid);
+void css_schedule_eval_all(void);
+void css_schedule_eval_all_unreg(unsigned long delay);
+int css_complete_work(void);
+
+int sch_is_pseudo_sch(struct subchannel *);
+struct schib;
+int css_sch_is_valid(struct schib *);
+
+extern struct workqueue_struct *cio_work_q;
+void css_wait_for_slow_path(void);
+void css_sched_sch_todo(struct subchannel *sch, enum sch_todo todo);
+#endif