[PATCH 084/437] locking/lock_events: convert to read/write iterators

[Jens Axboe]

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
 kernel/locking/lock_events.c    | 18 +++++++++---------
 kernel/locking/lock_events.h    |  4 ++--
 kernel/locking/qspinlock_stat.h |  7 +++----
 3 files changed, 14 insertions(+), 15 deletions(-)

diff --git a/kernel/locking/lock_events.c b/kernel/locking/lock_events.c
index e68d82099558..1f1efb123a1b 100644
--- a/kernel/locking/lock_events.c
+++ b/kernel/locking/lock_events.c
@@ -20,6 +20,7 @@
 #include <linux/sched.h>
 #include <linux/sched/clock.h>
 #include <linux/fs.h>
+#include <linux/uio.h>
 
 #include "lock_events.h"
 
@@ -58,8 +59,7 @@ DEFINE_PER_CPU(unsigned long, lockevents[lockevent_num]);
 /*
  * The lockevent_read() function can be overridden.
  */
-ssize_t __weak lockevent_read(struct file *file, char __user *user_buf,
-			      size_t count, loff_t *ppos)
+ssize_t __weak lockevent_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	char buf[64];
 	int cpu, id, len;
@@ -68,7 +68,7 @@ ssize_t __weak lockevent_read(struct file *file, char __user *user_buf,
 	/*
 	 * Get the counter ID stored in file->f_inode->i_private
 	 */
-	id = (long)file_inode(file)->i_private;
+	id = (long)file_inode(iocb->ki_filp)->i_private;
 
 	if (id >= lockevent_num)
 		return -EBADF;
@@ -77,7 +77,7 @@ ssize_t __weak lockevent_read(struct file *file, char __user *user_buf,
 		sum += per_cpu(lockevents[id], cpu);
 	len = snprintf(buf, sizeof(buf) - 1, "%llu\n", sum);
 
-	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+	return simple_copy_to_iter(buf, &iocb->ki_pos, len, to);
 }
 
 /*
@@ -85,15 +85,15 @@ ssize_t __weak lockevent_read(struct file *file, char __user *user_buf,
  *
  * When idx = reset_cnts, reset all the counts.
  */
-static ssize_t lockevent_write(struct file *file, const char __user *user_buf,
-			   size_t count, loff_t *ppos)
+static ssize_t lockevent_write(struct kiocb *iocb, struct iov_iter *from)
 {
+	size_t count = iov_iter_count(from);
 	int cpu;
 
 	/*
 	 * Get the counter ID stored in file->f_inode->i_private
 	 */
-	if ((long)file_inode(file)->i_private != LOCKEVENT_reset_cnts)
+	if ((long)file_inode(iocb->ki_filp)->i_private != LOCKEVENT_reset_cnts)
 		return count;
 
 	for_each_possible_cpu(cpu) {
@@ -110,8 +110,8 @@ static ssize_t lockevent_write(struct file *file, const char __user *user_buf,
  * Debugfs data structures
  */
 static const struct file_operations fops_lockevent = {
-	.read = lockevent_read,
-	.write = lockevent_write,
+	.read_iter = lockevent_read,
+	.write_iter = lockevent_write,
 	.llseek = default_llseek,
 };
 
diff --git a/kernel/locking/lock_events.h b/kernel/locking/lock_events.h
index a6016b91803d..0210d1abc4d7 100644
--- a/kernel/locking/lock_events.h
+++ b/kernel/locking/lock_events.h
@@ -58,7 +58,7 @@ static inline void __lockevent_add(enum lock_events event, int inc)
 
 #endif /* CONFIG_LOCK_EVENT_COUNTS */
 
-ssize_t lockevent_read(struct file *file, char __user *user_buf,
-		       size_t count, loff_t *ppos);
+struct kiocb;
+ssize_t lockevent_read(struct kiocb *iocb, struct iov_iter *to);
 
 #endif /* __LOCKING_LOCK_EVENTS_H */
diff --git a/kernel/locking/qspinlock_stat.h b/kernel/locking/qspinlock_stat.h
index e625bb410aa2..efaabdcfcddc 100644
--- a/kernel/locking/qspinlock_stat.h
+++ b/kernel/locking/qspinlock_stat.h
@@ -33,8 +33,7 @@ static DEFINE_PER_CPU(u64, pv_kick_time);
  * 3. pv_hash_hops
  *    Average hops/hash = pv_hash_hops/pv_kick_unlock
  */
-ssize_t lockevent_read(struct file *file, char __user *user_buf,
-		       size_t count, loff_t *ppos)
+ssize_t lockevent_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	char buf[64];
 	int cpu, id, len;
@@ -43,7 +42,7 @@ ssize_t lockevent_read(struct file *file, char __user *user_buf,
 	/*
 	 * Get the counter ID stored in file->f_inode->i_private
 	 */
-	id = (long)file_inode(file)->i_private;
+	id = (long)file_inode(iocb->ki_filp)->i_private;
 
 	if (id >= lockevent_num)
 		return -EBADF;
@@ -91,7 +90,7 @@ ssize_t lockevent_read(struct file *file, char __user *user_buf,
 		len = snprintf(buf, sizeof(buf) - 1, "%llu\n", sum);
 	}
 
-	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
+	return simple_copy_to_iter(buf, &iocb->ki_pos, len, to);
 }
 
 /*
-- 
2.43.0