Merge tag 's390-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Improve stop_machine wait logic: replace cpu_relax_yield call in
   generic stop_machine function with a weak stop_machine_yield
   function. This is overridden on s390, which yields the current cpu to
   the neighbouring cpu after a couple of retries, instead of blindly
   giving up the cpu to the hipervisor. This significantly improves
   stop_machine performance on s390 in overcommitted scenarios.

   This includes common code changes which have been Acked by Peter
   Zijlstra and Thomas Gleixner.

 - Improve jump label transformation speed: transform jump labels
   without using stop_machine.

 - Refactoring of the vfio-ccw cp handling, simplifying the code and
   avoiding unneeded allocating/copying.

 - Various vfio-ccw fixes (ccw translation, state machine).

 - Add support for vfio-ap queue interrupt control in the guest. This
   includes s390 kvm changes which have been Acked by Christian
   Borntraeger.

 - Add protected virtualization support for virtio-ccw.

 - Enforce both CONFIG_SMP and CONFIG_HOTPLUG_CPU, which allows to
   remove some code which most likely isn't working at all, besides that
   s390 didn't even compile for !CONFIG_SMP.

 - Support for special flagged EP11 CPRBs for zcrypt.

 - Handle PCI devices with no support for new MIO instructions.

 - Avoid KASAN false positives in reworked stack unwinder.

 - Couple of fixes for the QDIO layer.

 - Convert s390 specific documentation to ReST format.

 - Let s390 crypto modules return -ENODEV instead of -EOPNOTSUPP if
   hardware is missing. This way our modules behave like most other
   modules and which is also what systemd's systemd-modules-load.service
   expects.

 - Replace defconfig with performance_defconfig, so there is one config
   file less to maintain.

 - Remove the SCLP call home device driver, which was never useful.

 - Cleanups all over the place.

* tag 's390-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (83 commits)
  docs: s390: s390dbf: typos and formatting, update crash command
  docs: s390: unify and update s390dbf kdocs at debug.c
  docs: s390: restore important non-kdoc parts of s390dbf.rst
  vfio-ccw: Fix the conversion of Format-0 CCWs to Format-1
  s390/pci: correctly handle MIO opt-out
  s390/pci: deal with devices that have no support for MIO instructions
  s390: ap: kvm: Enable PQAP/AQIC facility for the guest
  s390: ap: implement PAPQ AQIC interception in kernel
  vfio: ap: register IOMMU VFIO notifier
  s390: ap: kvm: add PQAP interception for AQIC
  s390/unwind: cleanup unused READ_ONCE_TASK_STACK
  s390/kasan: avoid false positives during stack unwind
  s390/qdio: don't touch the dsci in tiqdio_add_input_queues()
  s390/qdio: (re-)initialize tiqdio list entries
  s390/dasd: Fix a precision vs width bug in dasd_feature_list()
  s390/cio: introduce driver_override on the css bus
  vfio-ccw: make convert_ccw0_to_ccw1 static
  vfio-ccw: Remove copy_ccw_from_iova()
  vfio-ccw: Factor out the ccw0-to-ccw1 transition
  vfio-ccw: Copy CCW data outside length calculation
  ...

1 files changed, 151 insertions, 2 deletions

diff --git a/arch/s390/include/asm/debug.h b/arch/s390/include/asm/debug.h
index c305d39f5016..310134015541 100644
--- a/arch/s390/include/asm/debug.h
+++ b/arch/s390/include/asm/debug.h
@@ -107,13 +107,37 @@ void debug_unregister(debug_info_t *id);
 void debug_set_level(debug_info_t *id, int new_level);
 
 void debug_set_critical(void);
+
 void debug_stop_all(void);
 
+/**
+ * debug_level_enabled() - Returns true if debug events for the specified
+ *			   level would be logged. Otherwise returns false.
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ *
+ * Return:
+ * - %true if level is less or equal to the current debug level.
+ */
 static inline bool debug_level_enabled(debug_info_t *id, int level)
 {
 	return level <= id->level;
 }
 
+/**
+ * debug_event() - writes binary debug entry to active debug area
+ *		   (if level <= actual debug level)
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @data:	pointer to data for debug entry
+ * @length:	length of data in bytes
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_event(debug_info_t *id, int level,
 					 void *data, int length)
 {
@@ -122,6 +146,18 @@ static inline debug_entry_t *debug_event(debug_info_t *id, int level,
 	return debug_event_common(id, level, data, length);
 }
 
+/**
+ * debug_int_event() - writes unsigned integer debug entry to active debug area
+ *		       (if level <= actual debug level)
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @tag:	integer value for debug entry
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
 					     unsigned int tag)
 {
@@ -132,6 +168,18 @@ static inline debug_entry_t *debug_int_event(debug_info_t *id, int level,
 	return debug_event_common(id, level, &t, sizeof(unsigned int));
 }
 
+/**
+ * debug_long_event() - writes unsigned long debug entry to active debug area
+ *		       (if level <= actual debug level)
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @tag:	long integer value for debug entry
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
 					      unsigned long tag)
 {
@@ -142,6 +190,18 @@ static inline debug_entry_t *debug_long_event(debug_info_t *id, int level,
 	return debug_event_common(id, level, &t, sizeof(unsigned long));
 }
 
+/**
+ * debug_text_event() - writes string debug entry in ascii format to active
+ *			debug area (if level <= actual debug level)
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @txt:	string for debug entry
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
 					      const char *txt)
 {
@@ -152,12 +212,28 @@ static inline debug_entry_t *debug_text_event(debug_info_t *id, int level,
 
 /*
  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
- * stored in the s390dbf. See Documentation/s390/s390dbf.txt for more details!
+ * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
  */
 extern debug_entry_t *
 __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
 	__attribute__ ((format(printf, 3, 4)));
 
+/**
+ * debug_sprintf_event() - writes debug entry with format string
+ *			   and varargs (longs) to active debug area
+ *			   (if level $<=$ actual debug level).
+ *
+ * @_id:	handle for debug log
+ * @_level:	debug level
+ * @_fmt:	format string for debug entry
+ * @...:	varargs used as in sprintf()
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ *
+ * floats and long long datatypes cannot be used as varargs.
+ */
 #define debug_sprintf_event(_id, _level, _fmt, ...)			\
 ({									\
 	debug_entry_t *__ret;						\
@@ -172,6 +248,20 @@ __debug_sprintf_event(debug_info_t *id, int level, char *string, ...)
 	__ret;								\
 })
 
+/**
+ * debug_exception() - writes binary debug entry to active debug area
+ *		       (if level <= actual debug level)
+ *		       and switches to next debug area
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @data:	pointer to data for debug entry
+ * @length:	length of data in bytes
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
 					     void *data, int length)
 {
@@ -180,6 +270,19 @@ static inline debug_entry_t *debug_exception(debug_info_t *id, int level,
 	return debug_exception_common(id, level, data, length);
 }
 
+/**
+ * debug_int_exception() - writes unsigned int debug entry to active debug area
+ *			   (if level <= actual debug level)
+ *			   and switches to next debug area
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @tag:	integer value for debug entry
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
 						 unsigned int tag)
 {
@@ -190,6 +293,19 @@ static inline debug_entry_t *debug_int_exception(debug_info_t *id, int level,
 	return debug_exception_common(id, level, &t, sizeof(unsigned int));
 }
 
+/**
+ * debug_long_exception() - writes long debug entry to active debug area
+ *			   (if level <= actual debug level)
+ *			   and switches to next debug area
+ *
+ * @id:		handle for debug log
+ * @level:	debug level
+ * @tag:	long integer value for debug entry
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
 						   unsigned long tag)
 {
@@ -200,6 +316,20 @@ static inline debug_entry_t *debug_long_exception (debug_info_t *id, int level,
 	return debug_exception_common(id, level, &t, sizeof(unsigned long));
 }
 
+/**
+ * debug_text_exception() - writes string debug entry in ascii format to active
+ *			    debug area (if level <= actual debug level)
+ *			    and switches to next debug area
+ * area
+ *
+ * @id:	handle for debug log
+ * @level:	debug level
+ * @txt:	string for debug entry
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ */
 static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
 						  const char *txt)
 {
@@ -210,12 +340,30 @@ static inline debug_entry_t *debug_text_exception(debug_info_t *id, int level,
 
 /*
  * IMPORTANT: Use "%s" in sprintf format strings with care! Only pointers are
- * stored in the s390dbf. See Documentation/s390/s390dbf.txt for more details!
+ * stored in the s390dbf. See Documentation/s390/s390dbf.rst for more details!
  */
 extern debug_entry_t *
 __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
 	__attribute__ ((format(printf, 3, 4)));
 
+
+/**
+ * debug_sprintf_exception() - writes debug entry with format string and
+ *			       varargs (longs) to active debug area
+ *			       (if level <= actual debug level)
+ *			       and switches to next debug area.
+ *
+ * @_id:	handle for debug log
+ * @_level:	debug level
+ * @_fmt:	format string for debug entry
+ * @...:	varargs used as in sprintf()
+ *
+ * Return:
+ * - Address of written debug entry
+ * - %NULL if error
+ *
+ * floats and long long datatypes cannot be used as varargs.
+ */
 #define debug_sprintf_exception(_id, _level, _fmt, ...)			\
 ({									\
 	debug_entry_t *__ret;						\
@@ -231,6 +379,7 @@ __debug_sprintf_exception(debug_info_t *id, int level, char *string, ...)
 })
 
 int debug_register_view(debug_info_t *id, struct debug_view *view);
+
 int debug_unregister_view(debug_info_t *id, struct debug_view *view);
 
 /*