[PATCH 1/2] proc: add tgid_iter.pid_ns member

[Alexey Dobriyan <adobriyan@gmail.com>]

next_tgid() accept pid namespace as an argument, but it never changes
during readdir (which would be unthinkable thing to do anyway).

Move it inside iterator type and hide from direct usage.
---
 fs/proc/base.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/fs/proc/base.c b/fs/proc/base.c
index d9acfa89c894..f2db455dbbfd 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -3543,8 +3543,10 @@ struct dentry *proc_pid_lookup(struct dentry *dentry, unsigned int flags)
 struct tgid_iter {
 	unsigned int tgid;
 	struct task_struct *task;
+	struct pid_namespace *pid_ns;
 };
-static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
+
+static struct tgid_iter next_tgid(struct tgid_iter iter)
 {
 	struct pid *pid;
 
@@ -3553,9 +3555,9 @@ static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter ite
 	rcu_read_lock();
 retry:
 	iter.task = NULL;
-	pid = find_ge_pid(iter.tgid, ns);
+	pid = find_ge_pid(iter.tgid, iter.pid_ns);
 	if (pid) {
-		iter.tgid = pid_nr_ns(pid, ns);
+		iter.tgid = pid_nr_ns(pid, iter.pid_ns);
 		iter.task = pid_task(pid, PIDTYPE_TGID);
 		if (!iter.task) {
 			iter.tgid += 1;
@@ -3574,7 +3576,7 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx)
 {
 	struct tgid_iter iter;
 	struct proc_fs_info *fs_info = proc_sb_info(file_inode(file)->i_sb);
-	struct pid_namespace *ns = proc_pid_ns(file_inode(file)->i_sb);
+	struct pid_namespace *pid_ns = proc_pid_ns(file_inode(file)->i_sb);
 	loff_t pos = ctx->pos;
 
 	if (pos >= PID_MAX_LIMIT + TGID_OFFSET)
@@ -3592,9 +3594,10 @@ int proc_pid_readdir(struct file *file, struct dir_context *ctx)
 	}
 	iter.tgid = pos - TGID_OFFSET;
 	iter.task = NULL;
-	for (iter = next_tgid(ns, iter);
+	iter.pid_ns = pid_ns;
+	for (iter = next_tgid(iter);
 	     iter.task;
-	     iter.tgid += 1, iter = next_tgid(ns, iter)) {
+	     iter.tgid += 1, iter = next_tgid(iter)) {
 		char name[10 + 1];
 		unsigned int len;
 
-- 
2.52.0