Merge tag 'kvmarm-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 updates for Linux 5.11

- PSCI relay at EL2 when "protected KVM" is enabled
- New exception injection code
- Simplification of AArch32 system register handling
- Fix PMU accesses when no PMU is enabled
- Expose CSV3 on non-Meltdown hosts
- Cache hierarchy discovery fixes
- PV steal-time cleanups
- Allow function pointers at EL2
- Various host EL2 entry cleanups
- Simplification of the EL2 vector allocation

15 files changed, 138 insertions, 117 deletions

diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index 798027bb89be..640f09479bdf 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -13,6 +13,7 @@
 
 #ifndef __ASSEMBLY__
 
+#include <linux/compiler.h>
 #include <asm/rwonce.h>
 
 #ifndef nop
diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h
index 35e4a53b83e6..6432a7fade91 100644
--- a/include/asm-generic/percpu.h
+++ b/include/asm-generic/percpu.h
@@ -114,21 +114,21 @@ do {									\
 
 #define __this_cpu_generic_read_nopreempt(pcp)				\
 ({									\
-	typeof(pcp) __ret;						\
+	typeof(pcp) ___ret;						\
 	preempt_disable_notrace();					\
-	__ret = READ_ONCE(*raw_cpu_ptr(&(pcp)));			\
+	___ret = READ_ONCE(*raw_cpu_ptr(&(pcp)));			\
 	preempt_enable_notrace();					\
-	__ret;								\
+	___ret;								\
 })
 
 #define __this_cpu_generic_read_noirq(pcp)				\
 ({									\
-	typeof(pcp) __ret;						\
-	unsigned long __flags;						\
-	raw_local_irq_save(__flags);					\
-	__ret = raw_cpu_generic_read(pcp);				\
-	raw_local_irq_restore(__flags);					\
-	__ret;								\
+	typeof(pcp) ___ret;						\
+	unsigned long ___flags;						\
+	raw_local_irq_save(___flags);					\
+	___ret = raw_cpu_generic_read(pcp);				\
+	raw_local_irq_restore(___flags);				\
+	___ret;								\
 })
 
 #define this_cpu_generic_read(pcp)					\
diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h
index 1d94acd0bc85..fc85f50fa0e9 100644
--- a/include/kvm/arm_pmu.h
+++ b/include/kvm/arm_pmu.h
@@ -24,13 +24,11 @@ struct kvm_pmu {
 	int irq_num;
 	struct kvm_pmc pmc[ARMV8_PMU_MAX_COUNTERS];
 	DECLARE_BITMAP(chained, ARMV8_PMU_MAX_COUNTER_PAIRS);
-	bool ready;
 	bool created;
 	bool irq_level;
 	struct irq_work overflow_work;
 };
 
-#define kvm_arm_pmu_v3_ready(v)		((v)->arch.pmu.ready)
 #define kvm_arm_pmu_irq_initialized(v)	((v)->arch.pmu.irq_num >= VGIC_NR_SGIS)
 u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx);
 void kvm_pmu_set_counter_value(struct kvm_vcpu *vcpu, u64 select_idx, u64 val);
@@ -61,7 +59,6 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu);
 struct kvm_pmu {
 };
 
-#define kvm_arm_pmu_v3_ready(v)		(false)
 #define kvm_arm_pmu_irq_initialized(v)	(false)
 static inline u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu,
 					    u64 select_idx)
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index a8d8fdcd3723..3d74f1060bd1 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -402,6 +402,7 @@ int kvm_vgic_v4_unset_forwarding(struct kvm *kvm, int irq,
 				 struct kvm_kernel_irq_routing_entry *irq_entry);
 
 int vgic_v4_load(struct kvm_vcpu *vcpu);
+void vgic_v4_commit(struct kvm_vcpu *vcpu);
 int vgic_v4_put(struct kvm_vcpu *vcpu, bool need_db);
 
 #endif /* __KVM_ARM_VGIC_H */
diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h
index 230604e7f057..dd7233c48bf3 100644
--- a/include/linux/compiler-clang.h
+++ b/include/linux/compiler-clang.h
@@ -60,12 +60,6 @@
 #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
 #endif
 
-/* The following are for compatibility with GCC, from compiler-gcc.h,
- * and may be redefined here because they should not be shared with other
- * compilers, like ICC.
- */
-#define barrier() __asm__ __volatile__("" : : : "memory")
-
 #if __has_feature(shadow_call_stack)
 # define __noscs	__attribute__((__no_sanitize__("shadow-call-stack")))
 #endif
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index 5deb37024574..74c6c0486eed 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -15,25 +15,6 @@
 # error Sorry, your version of GCC is too old - please use 4.9 or newer.
 #endif
 
-/* Optimization barrier */
-
-/* The "volatile" is due to gcc bugs */
-#define barrier() __asm__ __volatile__("": : :"memory")
-/*
- * This version is i.e. to prevent dead stores elimination on @ptr
- * where gcc and llvm may behave differently when otherwise using
- * normal barrier(): while gcc behavior gets along with a normal
- * barrier(), llvm needs an explicit input variable to be assumed
- * clobbered. The issue is as follows: while the inline asm might
- * access any memory it wants, the compiler could have fit all of
- * @ptr into memory registers instead, and since @ptr never escaped
- * from that, it proved that the inline asm wasn't touching any of
- * it. This version works well with both compilers, i.e. we're telling
- * the compiler that the inline asm absolutely may see the contents
- * of @ptr. See also: https://llvm.org/bugs/show_bug.cgi?id=15495
- */
-#define barrier_data(ptr) __asm__ __volatile__("": :"r"(ptr) :"memory")
-
 /*
  * This macro obfuscates arithmetic on a variable address so that gcc
  * shouldn't recognize the original var, and make assumptions about it.
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index e512f5505dad..b8fe0c23cfff 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -80,11 +80,25 @@ void ftrace_likely_update(struct ftrace_likely_data *f, int val,
 
 /* Optimization barrier */
 #ifndef barrier
-# define barrier() __memory_barrier()
+/* The "volatile" is due to gcc bugs */
+# define barrier() __asm__ __volatile__("": : :"memory")
 #endif
 
 #ifndef barrier_data
-# define barrier_data(ptr) barrier()
+/*
+ * This version is i.e. to prevent dead stores elimination on @ptr
+ * where gcc and llvm may behave differently when otherwise using
+ * normal barrier(): while gcc behavior gets along with a normal
+ * barrier(), llvm needs an explicit input variable to be assumed
+ * clobbered. The issue is as follows: while the inline asm might
+ * access any memory it wants, the compiler could have fit all of
+ * @ptr into memory registers instead, and since @ptr never escaped
+ * from that, it proved that the inline asm wasn't touching any of
+ * it. This version works well with both compilers, i.e. we're telling
+ * the compiler that the inline asm absolutely may see the contents
+ * of @ptr. See also: https://llvm.org/bugs/show_bug.cgi?id=15495
+ */
+# define barrier_data(ptr) __asm__ __volatile__("": :"r"(ptr) :"memory")
 #endif
 
 /* workaround for GCC PR82365 if needed */
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 21cc971fd960..8667d0cdc71e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1580,8 +1580,24 @@ extern struct timespec64 current_time(struct inode *inode);
  * Snapshotting support.
  */
 
-void __sb_end_write(struct super_block *sb, int level);
-int __sb_start_write(struct super_block *sb, int level, bool wait);
+/*
+ * These are internal functions, please use sb_start_{write,pagefault,intwrite}
+ * instead.
+ */
+static inline void __sb_end_write(struct super_block *sb, int level)
+{
+	percpu_up_read(sb->s_writers.rw_sem + level-1);
+}
+
+static inline void __sb_start_write(struct super_block *sb, int level)
+{
+	percpu_down_read(sb->s_writers.rw_sem + level - 1);
+}
+
+static inline bool __sb_start_write_trylock(struct super_block *sb, int level)
+{
+	return percpu_down_read_trylock(sb->s_writers.rw_sem + level - 1);
+}
 
 #define __sb_writers_acquired(sb, lev)	\
 	percpu_rwsem_acquire(&(sb)->s_writers.rw_sem[(lev)-1], 1, _THIS_IP_)
@@ -1645,12 +1661,12 @@ static inline void sb_end_intwrite(struct super_block *sb)
  */
 static inline void sb_start_write(struct super_block *sb)
 {
-	__sb_start_write(sb, SB_FREEZE_WRITE, true);
+	__sb_start_write(sb, SB_FREEZE_WRITE);
 }
 
-static inline int sb_start_write_trylock(struct super_block *sb)
+static inline bool sb_start_write_trylock(struct super_block *sb)
 {
-	return __sb_start_write(sb, SB_FREEZE_WRITE, false);
+	return __sb_start_write_trylock(sb, SB_FREEZE_WRITE);
 }
 
 /**
@@ -1674,7 +1690,7 @@ static inline int sb_start_write_trylock(struct super_block *sb)
  */
 static inline void sb_start_pagefault(struct super_block *sb)
 {
-	__sb_start_write(sb, SB_FREEZE_PAGEFAULT, true);
+	__sb_start_write(sb, SB_FREEZE_PAGEFAULT);
 }
 
 /*
@@ -1692,12 +1708,12 @@ static inline void sb_start_pagefault(struct super_block *sb)
  */
 static inline void sb_start_intwrite(struct super_block *sb)
 {
-	__sb_start_write(sb, SB_FREEZE_FS, true);
+	__sb_start_write(sb, SB_FREEZE_FS);
 }
 
-static inline int sb_start_intwrite_trylock(struct super_block *sb)
+static inline bool sb_start_intwrite_trylock(struct super_block *sb)
 {
-	return __sb_start_write(sb, SB_FREEZE_FS, false);
+	return __sb_start_write_trylock(sb, SB_FREEZE_FS);
 }
 
 
@@ -2756,14 +2772,14 @@ static inline void file_start_write(struct file *file)
 {
 	if (!S_ISREG(file_inode(file)->i_mode))
 		return;
-	__sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, true);
+	sb_start_write(file_inode(file)->i_sb);
 }
 
 static inline bool file_start_write_trylock(struct file *file)
 {
 	if (!S_ISREG(file_inode(file)->i_mode))
 		return true;
-	return __sb_start_write(file_inode(file)->i_sb, SB_FREEZE_WRITE, false);
+	return sb_start_write_trylock(file_inode(file)->i_sb);
 }
 
 static inline void file_end_write(struct file *file)
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 38f23d757013..03da3f603d30 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -315,7 +315,7 @@ static inline int get_disk_ro(struct gendisk *disk)
 extern void disk_block_events(struct gendisk *disk);
 extern void disk_unblock_events(struct gendisk *disk);
 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
-void set_capacity_revalidate_and_notify(struct gendisk *disk, sector_t size,
+bool set_capacity_revalidate_and_notify(struct gendisk *disk, sector_t size,
 		bool update_bdev);
 
 /* drivers/char/random.c */
diff --git a/include/linux/irqchip/arm-gic-v4.h b/include/linux/irqchip/arm-gic-v4.h
index 6976b8331b60..943c3411ca10 100644
--- a/include/linux/irqchip/arm-gic-v4.h
+++ b/include/linux/irqchip/arm-gic-v4.h
@@ -39,6 +39,8 @@ struct its_vpe {
 	irq_hw_number_t		vpe_db_lpi;
 	/* VPE resident */
 	bool			resident;
+	/* VPT parse complete */
+	bool			ready;
 	union {
 		/* GICv4.0 implementations */
 		struct {
@@ -104,6 +106,7 @@ enum its_vcpu_info_cmd_type {
 	PROP_UPDATE_AND_INV_VLPI,
 	SCHEDULE_VPE,
 	DESCHEDULE_VPE,
+	COMMIT_VPE,
 	INVALL_VPE,
 	PROP_UPDATE_VSGI,
 };
@@ -129,6 +132,7 @@ int its_alloc_vcpu_irqs(struct its_vm *vm);
 void its_free_vcpu_irqs(struct its_vm *vm);
 int its_make_vpe_resident(struct its_vpe *vpe, bool g0en, bool g1en);
 int its_make_vpe_non_resident(struct its_vpe *vpe, bool db);
+int its_commit_vpe(struct its_vpe *vpe);
 int its_invall_vpe(struct its_vpe *vpe);
 int its_map_vlpi(int irq, struct its_vlpi_map *map);
 int its_get_vlpi(int irq, struct its_vlpi_map *map);
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index e391e3c56de5..a80c59af2c60 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -900,12 +900,19 @@ static inline void count_memcg_event_mm(struct mm_struct *mm,
 static inline void memcg_memory_event(struct mem_cgroup *memcg,
 				      enum memcg_memory_event event)
 {
+	bool swap_event = event == MEMCG_SWAP_HIGH || event == MEMCG_SWAP_MAX ||
+			  event == MEMCG_SWAP_FAIL;
+
 	atomic_long_inc(&memcg->memory_events_local[event]);
-	cgroup_file_notify(&memcg->events_local_file);
+	if (!swap_event)
+		cgroup_file_notify(&memcg->events_local_file);
 
 	do {
 		atomic_long_inc(&memcg->memory_events[event]);
-		cgroup_file_notify(&memcg->events_file);
+		if (swap_event)
+			cgroup_file_notify(&memcg->swap_events_file);
+		else
+			cgroup_file_notify(&memcg->events_file);
 
 		if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
 			break;
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 0c19d279b97f..96450f6fb1de 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1022,13 +1022,7 @@ struct perf_sample_data {
 	struct perf_callchain_entry	*callchain;
 	u64				aux_size;
 
-	/*
-	 * regs_user may point to task_pt_regs or to regs_user_copy, depending
-	 * on arch details.
-	 */
 	struct perf_regs		regs_user;
-	struct pt_regs			regs_user_copy;
-
 	struct perf_regs		regs_intr;
 	u64				stack_user_size;
 
@@ -1400,11 +1394,14 @@ perf_event_addr_filters(struct perf_event *event)
 extern void perf_event_addr_filters_sync(struct perf_event *event);
 
 extern int perf_output_begin(struct perf_output_handle *handle,
+			     struct perf_sample_data *data,
 			     struct perf_event *event, unsigned int size);
 extern int perf_output_begin_forward(struct perf_output_handle *handle,
-				    struct perf_event *event,
-				    unsigned int size);
+				     struct perf_sample_data *data,
+				     struct perf_event *event,
+				     unsigned int size);
 extern int perf_output_begin_backward(struct perf_output_handle *handle,
+				      struct perf_sample_data *data,
 				      struct perf_event *event,
 				      unsigned int size);
 
diff --git a/include/linux/perf_regs.h b/include/linux/perf_regs.h
index 2d12e97d5e7b..f632c5725f16 100644
--- a/include/linux/perf_regs.h
+++ b/include/linux/perf_regs.h
@@ -20,8 +20,7 @@ u64 perf_reg_value(struct pt_regs *regs, int idx);
 int perf_reg_validate(u64 mask);
 u64 perf_reg_abi(struct task_struct *task);
 void perf_get_regs_user(struct perf_regs *regs_user,
-			struct pt_regs *regs,
-			struct pt_regs *regs_user_copy);
+			struct pt_regs *regs);
 #else
 
 #define PERF_REG_EXTENDED_MASK	0
@@ -42,8 +41,7 @@ static inline u64 perf_reg_abi(struct task_struct *task)
 }
 
 static inline void perf_get_regs_user(struct perf_regs *regs_user,
-				      struct pt_regs *regs,
-				      struct pt_regs *regs_user_copy)
+				      struct pt_regs *regs)
 {
 	regs_user->regs = task_pt_regs(current);
 	regs_user->abi = perf_reg_abi(current);
diff --git a/include/linux/psci.h b/include/linux/psci.h
index 2a1bfb890e58..4ca0060a3fc4 100644
--- a/include/linux/psci.h
+++ b/include/linux/psci.h
@@ -34,6 +34,15 @@ struct psci_operations {
 
 extern struct psci_operations psci_ops;
 
+struct psci_0_1_function_ids {
+	u32 cpu_suspend;
+	u32 cpu_on;
+	u32 cpu_off;
+	u32 migrate;
+};
+
+struct psci_0_1_function_ids get_psci_0_1_function_ids(void);
+
 #if defined(CONFIG_ARM_PSCI_FW)
 int __init psci_dt_init(void);
 #else
diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h
index 07865c601099..2072c260f5d0 100644
--- a/include/uapi/linux/gpio.h
+++ b/include/uapi/linux/gpio.h
@@ -26,7 +26,7 @@
  * struct gpiochip_info - Information about a certain GPIO chip
  * @name: the Linux kernel name of this GPIO chip
  * @label: a functional name for this GPIO chip, such as a product
- * number, may be empty
+ * number, may be empty (i.e. label[0] == '\0')
  * @lines: number of GPIO lines on this chip
  */
 struct gpiochip_info {
@@ -98,7 +98,7 @@ struct gpio_v2_line_values {
  * identifying which field of the attribute union is in use.
  * @GPIO_V2_LINE_ATTR_ID_FLAGS: flags field is in use
  * @GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES: values field is in use
- * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us is in use
+ * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us field is in use
  */
 enum gpio_v2_line_attr_id {
 	GPIO_V2_LINE_ATTR_ID_FLAGS		= 1,
@@ -110,17 +110,17 @@ enum gpio_v2_line_attr_id {
  * struct gpio_v2_line_attribute - a configurable attribute of a line
  * @id: attribute identifier with value from &enum gpio_v2_line_attr_id
  * @padding: reserved for future use and must be zero filled
- * @flags: if id is GPIO_V2_LINE_ATTR_ID_FLAGS, the flags for the GPIO
- * line, with values from enum gpio_v2_line_flag, such as
- * GPIO_V2_LINE_FLAG_ACTIVE_LOW, GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed
+ * @flags: if id is %GPIO_V2_LINE_ATTR_ID_FLAGS, the flags for the GPIO
+ * line, with values from &enum gpio_v2_line_flag, such as
+ * %GPIO_V2_LINE_FLAG_ACTIVE_LOW, %GPIO_V2_LINE_FLAG_OUTPUT etc, added
  * together.  This overrides the default flags contained in the &struct
  * gpio_v2_line_config for the associated line.
- * @values: if id is GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES, a bitmap
+ * @values: if id is %GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES, a bitmap
  * containing the values to which the lines will be set, with each bit
  * number corresponding to the index into &struct
  * gpio_v2_line_request.offsets.
- * @debounce_period_us: if id is GPIO_V2_LINE_ATTR_ID_DEBOUNCE, the desired
- * debounce period, in microseconds
+ * @debounce_period_us: if id is %GPIO_V2_LINE_ATTR_ID_DEBOUNCE, the
+ * desired debounce period, in microseconds
  */
 struct gpio_v2_line_attribute {
 	__u32 id;
@@ -147,12 +147,12 @@ struct gpio_v2_line_config_attribute {
 
 /**
  * struct gpio_v2_line_config - Configuration for GPIO lines
- * @flags: flags for the GPIO lines, with values from enum
- * gpio_v2_line_flag, such as GPIO_V2_LINE_FLAG_ACTIVE_LOW,
- * GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed together.  This is the default for
+ * @flags: flags for the GPIO lines, with values from &enum
+ * gpio_v2_line_flag, such as %GPIO_V2_LINE_FLAG_ACTIVE_LOW,
+ * %GPIO_V2_LINE_FLAG_OUTPUT etc, added together.  This is the default for
  * all requested lines but may be overridden for particular lines using
- * attrs.
- * @num_attrs: the number of attributes in attrs
+ * @attrs.
+ * @num_attrs: the number of attributes in @attrs
  * @padding: reserved for future use and must be zero filled
  * @attrs: the configuration attributes associated with the requested
  * lines.  Any attribute should only be associated with a particular line
@@ -175,17 +175,17 @@ struct gpio_v2_line_config {
  * "my-bitbanged-relay"
  * @config: requested configuration for the lines.
  * @num_lines: number of lines requested in this request, i.e. the number
- * of valid fields in the GPIO_V2_LINES_MAX sized arrays, set to 1 to
+ * of valid fields in the %GPIO_V2_LINES_MAX sized arrays, set to 1 to
  * request a single line
  * @event_buffer_size: a suggested minimum number of line events that the
  * kernel should buffer.  This is only relevant if edge detection is
  * enabled in the configuration. Note that this is only a suggested value
  * and the kernel may allocate a larger buffer or cap the size of the
  * buffer. If this field is zero then the buffer size defaults to a minimum
- * of num_lines*16.
+ * of @num_lines * 16.
  * @padding: reserved for future use and must be zero filled
  * @fd: if successful this field will contain a valid anonymous file handle
- * after a GPIO_GET_LINE_IOCTL operation, zero or negative value means
+ * after a %GPIO_GET_LINE_IOCTL operation, zero or negative value means
  * error
  */
 struct gpio_v2_line_request {
@@ -203,15 +203,16 @@ struct gpio_v2_line_request {
  * struct gpio_v2_line_info - Information about a certain GPIO line
  * @name: the name of this GPIO line, such as the output pin of the line on
  * the chip, a rail or a pin header name on a board, as specified by the
- * GPIO chip, may be empty
+ * GPIO chip, may be empty (i.e. name[0] == '\0')
  * @consumer: a functional name for the consumer of this GPIO line as set
  * by whatever is using it, will be empty if there is no current user but
  * may also be empty if the consumer doesn't set this up
- * @flags: flags for the GPIO line, such as GPIO_V2_LINE_FLAG_ACTIVE_LOW,
- * GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed together
  * @offset: the local offset on this GPIO chip, fill this in when
  * requesting the line information from the kernel
- * @num_attrs: the number of attributes in attrs
+ * @num_attrs: the number of attributes in @attrs
+ * @flags: flags for the GPIO lines, with values from &enum
+ * gpio_v2_line_flag, such as %GPIO_V2_LINE_FLAG_ACTIVE_LOW,
+ * %GPIO_V2_LINE_FLAG_OUTPUT etc, added together.
  * @attrs: the configuration attributes associated with the line
  * @padding: reserved for future use
  */
@@ -244,7 +245,7 @@ enum gpio_v2_line_changed_type {
  * of a GPIO line
  * @info: updated line information
  * @timestamp_ns: estimate of time of status change occurrence, in nanoseconds
- * @event_type: the type of change with a value from enum
+ * @event_type: the type of change with a value from &enum
  * gpio_v2_line_changed_type
  * @padding: reserved for future use
  */
@@ -269,10 +270,10 @@ enum gpio_v2_line_event_id {
 /**
  * struct gpio_v2_line_event - The actual event being pushed to userspace
  * @timestamp_ns: best estimate of time of event occurrence, in nanoseconds.
- * The timestamp_ns is read from CLOCK_MONOTONIC and is intended to allow the
- * accurate measurement of the time between events.  It does not provide
+ * The @timestamp_ns is read from %CLOCK_MONOTONIC and is intended to allow
+ * the accurate measurement of the time between events. It does not provide
  * the wall-clock time.
- * @id: event identifier with value from enum gpio_v2_line_event_id
+ * @id: event identifier with value from &enum gpio_v2_line_event_id
  * @offset: the offset of the line that triggered the event
  * @seqno: the sequence number for this event in the sequence of events for
  * all the lines in this line request
@@ -291,7 +292,7 @@ struct gpio_v2_line_event {
 };
 
 /*
- *  ABI v1
+ * ABI v1
  *
  * This version of the ABI is deprecated.
  * Use the latest version of the ABI, defined above, instead.
@@ -314,13 +315,13 @@ struct gpio_v2_line_event {
  * @flags: various flags for this line
  * @name: the name of this GPIO line, such as the output pin of the line on the
  * chip, a rail or a pin header name on a board, as specified by the gpio
- * chip, may be empty
+ * chip, may be empty (i.e. name[0] == '\0')
  * @consumer: a functional name for the consumer of this GPIO line as set by
  * whatever is using it, will be empty if there is no current user but may
  * also be empty if the consumer doesn't set this up
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_info instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_info instead.
  */
 struct gpioline_info {
 	__u32 line_offset;
@@ -344,17 +345,18 @@ enum {
  * of a GPIO line
  * @info: updated line information
  * @timestamp: estimate of time of status change occurrence, in nanoseconds
- * @event_type: one of GPIOLINE_CHANGED_REQUESTED, GPIOLINE_CHANGED_RELEASED
- * and GPIOLINE_CHANGED_CONFIG
+ * @event_type: one of %GPIOLINE_CHANGED_REQUESTED,
+ * %GPIOLINE_CHANGED_RELEASED and %GPIOLINE_CHANGED_CONFIG
+ * @padding: reserved for future use
  *
- * Note: struct gpioline_info embedded here has 32-bit alignment on its own,
+ * The &struct gpioline_info embedded here has 32-bit alignment on its own,
  * but it works fine with 64-bit alignment too. With its 72 byte size, we can
  * guarantee there are no implicit holes between it and subsequent members.
  * The 20-byte padding at the end makes sure we don't add any implicit padding
  * at the end of the structure on 64-bit architectures.
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_info_changed instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_info_changed instead.
  */
 struct gpioline_info_changed {
 	struct gpioline_info info;
@@ -378,13 +380,13 @@ struct gpioline_info_changed {
  * @lineoffsets: an array of desired lines, specified by offset index for the
  * associated GPIO device
  * @flags: desired flags for the desired GPIO lines, such as
- * GPIOHANDLE_REQUEST_OUTPUT, GPIOHANDLE_REQUEST_ACTIVE_LOW etc, OR:ed
+ * %GPIOHANDLE_REQUEST_OUTPUT, %GPIOHANDLE_REQUEST_ACTIVE_LOW etc, added
  * together. Note that even if multiple lines are requested, the same flags
  * must be applicable to all of them, if you want lines with individual
  * flags set, request them one by one. It is possible to select
  * a batch of input or output lines, but they must all have the same
  * characteristics, i.e. all inputs or all outputs, all active low etc
- * @default_values: if the GPIOHANDLE_REQUEST_OUTPUT is set for a requested
+ * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set for a requested
  * line, this specifies the default output value, should be 0 (low) or
  * 1 (high), anything else than 0 or 1 will be interpreted as 1 (high)
  * @consumer_label: a desired consumer label for the selected GPIO line(s)
@@ -392,11 +394,11 @@ struct gpioline_info_changed {
  * @lines: number of lines requested in this request, i.e. the number of
  * valid fields in the above arrays, set to 1 to request a single line
  * @fd: if successful this field will contain a valid anonymous file handle
- * after a GPIO_GET_LINEHANDLE_IOCTL operation, zero or negative value
+ * after a %GPIO_GET_LINEHANDLE_IOCTL operation, zero or negative value
  * means error
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_request instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_request instead.
  */
 struct gpiohandle_request {
 	__u32 lineoffsets[GPIOHANDLES_MAX];
@@ -410,15 +412,15 @@ struct gpiohandle_request {
 /**
  * struct gpiohandle_config - Configuration for a GPIO handle request
  * @flags: updated flags for the requested GPIO lines, such as
- * GPIOHANDLE_REQUEST_OUTPUT, GPIOHANDLE_REQUEST_ACTIVE_LOW etc, OR:ed
+ * %GPIOHANDLE_REQUEST_OUTPUT, %GPIOHANDLE_REQUEST_ACTIVE_LOW etc, added
  * together
- * @default_values: if the GPIOHANDLE_REQUEST_OUTPUT is set in flags,
+ * @default_values: if the %GPIOHANDLE_REQUEST_OUTPUT is set in flags,
  * this specifies the default output value, should be 0 (low) or
  * 1 (high), anything else than 0 or 1 will be interpreted as 1 (high)
  * @padding: reserved for future use and should be zero filled
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_config instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_config instead.
  */
 struct gpiohandle_config {
 	__u32 flags;
@@ -432,8 +434,8 @@ struct gpiohandle_config {
  * state of a line, when setting the state of lines these should contain
  * the desired target state
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_values instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_values instead.
  */
 struct gpiohandle_data {
 	__u8 values[GPIOHANDLES_MAX];
@@ -449,17 +451,17 @@ struct gpiohandle_data {
  * @lineoffset: the desired line to subscribe to events from, specified by
  * offset index for the associated GPIO device
  * @handleflags: desired handle flags for the desired GPIO line, such as
- * GPIOHANDLE_REQUEST_ACTIVE_LOW or GPIOHANDLE_REQUEST_OPEN_DRAIN
+ * %GPIOHANDLE_REQUEST_ACTIVE_LOW or %GPIOHANDLE_REQUEST_OPEN_DRAIN
  * @eventflags: desired flags for the desired GPIO event line, such as
- * GPIOEVENT_REQUEST_RISING_EDGE or GPIOEVENT_REQUEST_FALLING_EDGE
+ * %GPIOEVENT_REQUEST_RISING_EDGE or %GPIOEVENT_REQUEST_FALLING_EDGE
  * @consumer_label: a desired consumer label for the selected GPIO line(s)
  * such as "my-listener"
  * @fd: if successful this field will contain a valid anonymous file handle
- * after a GPIO_GET_LINEEVENT_IOCTL operation, zero or negative value
+ * after a %GPIO_GET_LINEEVENT_IOCTL operation, zero or negative value
  * means error
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_request instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_request instead.
  */
 struct gpioevent_request {
 	__u32 lineoffset;
@@ -469,7 +471,7 @@ struct gpioevent_request {
 	int fd;
 };
 
-/**
+/*
  * GPIO event types
  */
 #define GPIOEVENT_EVENT_RISING_EDGE 0x01
@@ -480,8 +482,8 @@ struct gpioevent_request {
  * @timestamp: best estimate of time of event occurrence, in nanoseconds
  * @id: event identifier
  *
- * This struct is part of ABI v1 and is deprecated.
- * Use struct gpio_v2_line_event instead.
+ * Note: This struct is part of ABI v1 and is deprecated.
+ * Use &struct gpio_v2_line_event instead.
  */
 struct gpioevent_data {
 	__u64 timestamp;