[PATCH RESEND v2 11/30] latencytop: let procfs copy in writes to /proc/latency_stats

[Christian Brauner]

Implement ->proc_write_buf() so procfs copies in what is written before
it pins the entry. The write only clears the statistics and doesn't look
at what was written anyway. Writes larger than PAGE_SIZE - 1 bytes fail
with -EINVAL now.

Signed-off-by: Christian Brauner (Amutable) <brauner at kernel.org>
---
 kernel/latencytop.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/kernel/latencytop.c b/kernel/latencytop.c
index b764f47606d3..35f73ca07656 100644
--- a/kernel/latencytop.c
+++ b/kernel/latencytop.c
@@ -267,8 +267,7 @@ static int lstats_show(struct seq_file *m, void *v)
 }
 
 static ssize_t
-lstats_write(struct file *file, const char __user *buf, size_t count,
-	     loff_t *offs)
+lstats_write(struct file *file, char *buf, size_t count, loff_t *offs)
 {
 	clear_global_latency_tracing();
 
@@ -277,7 +276,7 @@ lstats_write(struct file *file, const char __user *buf, size_t count,
 
 static const struct proc_ops lstats_proc_ops = {
 	.proc_show	= lstats_show,
-	.proc_write	= lstats_write,
+	.proc_write_buf	= lstats_write,
 };
 
 static int __init init_lstats_procfs(void)

-- 
2.53.0