cgroup: replace cftype->read_seq_string() with cftype->seq_show()

In preparation of conversion to kernfs, cgroup file handling is
updated so that it can be easily mapped to kernfs.  This patch
replaces cftype->read_seq_string() with cftype->seq_show() which is
not limited to single_open() operation and will map directcly to
kernfs seq_file interface.

The conversions are mechanical.  As ->seq_show() doesn't have @css and
@cft, the functions which make use of them are converted to use
seq_css() and seq_cft() respectively.  In several occassions, e.f. if
it has seq_string in its name, the function name is updated to fit the
new method better.

This patch does not introduce any behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Aristeu Rozanski <arozansk@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Daniel Wagner <daniel.wagner@bmw-carit.de>
Acked-by: Li Zefan <lizefan@huawei.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Neil Horman <nhorman@tuxdriver.com>

1 files changed, 3 insertions, 4 deletions

diff --git a/security/device_cgroup.c b/security/device_cgroup.c
index 7c2a0a71049e..d3b6d2cd3a06 100644
--- a/security/device_cgroup.c
+++ b/security/device_cgroup.c
@@ -274,10 +274,9 @@ static void set_majmin(char *str, unsigned m)
                 sprintf(str, "%u", m);
 }
 
-static int devcgroup_seq_read(struct cgroup_subsys_state *css,
-                              struct cftype *cft, struct seq_file *m)
+static int devcgroup_seq_show(struct seq_file *m, void *v)
 {
-        struct dev_cgroup *devcgroup = css_to_devcgroup(css);
+        struct dev_cgroup *devcgroup = css_to_devcgroup(seq_css(m));
         struct dev_exception_item *ex;
         char maj[MAJMINLEN], min[MAJMINLEN], acc[ACCLEN];
 
@@ -679,7 +678,7 @@ static struct cftype dev_cgroup_files[] = {
         },
         {
                 .name = "list",
-                .read_seq_string = devcgroup_seq_read,
+                .seq_show = devcgroup_seq_show,
                 .private = DEVCG_LIST,
         },
         { }     /* terminate */