proc: convert /proc/$PID/io to seq_file interface

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/proc/base.c

@@ -2398,7 +2398,7 @@ static const struct file_operations proc_coredump_filter_operations = {
 #endif
 
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
+static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
 {
 	struct task_io_accounting acct = task->ioac;
 	unsigned long flags;
@@ -2422,7 +2422,7 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
 
 		unlock_task_sighand(task, &flags);
 	}
-	result = sprintf(buffer,
+	result = seq_printf(m,
 			"rchar: %llu\n"
 			"wchar: %llu\n"
 			"syscr: %llu\n"
@@ -2442,14 +2442,16 @@ static int do_io_accounting(struct task_struct *task, char *buffer, int whole)
 	return result;
 }
 
-static int proc_tid_io_accounting(struct task_struct *task, char *buffer)
+static int proc_tid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
+				  struct pid *pid, struct task_struct *task)
 {
-	return do_io_accounting(task, buffer, 0);
+	return do_io_accounting(task, m, 0);
 }
 
-static int proc_tgid_io_accounting(struct task_struct *task, char *buffer)
+static int proc_tgid_io_accounting(struct seq_file *m, struct pid_namespace *ns,
+				   struct pid *pid, struct task_struct *task)
 {
-	return do_io_accounting(task, buffer, 1);
+	return do_io_accounting(task, m, 1);
 }
 #endif /* CONFIG_TASK_IO_ACCOUNTING */
 
@@ -2631,7 +2633,7 @@ static const struct pid_entry tgid_base_stuff[] = {
 	REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations),
 #endif
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-	INF("io",	S_IRUSR, proc_tgid_io_accounting),
+	ONE("io",	S_IRUSR, proc_tgid_io_accounting),
 #endif
 #ifdef CONFIG_HARDWALL
 	INF("hardwall",   S_IRUGO, proc_pid_hardwall),
@@ -2966,7 +2968,7 @@ static const struct pid_entry tid_base_stuff[] = {
 	REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations),
 #endif
 #ifdef CONFIG_TASK_IO_ACCOUNTING
-	INF("io",	S_IRUSR, proc_tid_io_accounting),
+	ONE("io",	S_IRUSR, proc_tid_io_accounting),
 #endif
 #ifdef CONFIG_HARDWALL
 	INF("hardwall",   S_IRUGO, proc_pid_hardwall),