cgroup: remove cftype->read(), ->read_map() and ->write()
In preparation of conversion to kernfs, cgroup file handling is being
consolidated so that it can be easily mapped to the seq_file based
interface of kernfs.
After recent updates, ->read() and ->read_map() don't have any user
left and ->write() never had any user. Remove them.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index f9f5fe3..b132ff9 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -2324,8 +2324,6 @@
struct cftype *cft = __d_cft(file->f_dentry);
struct cgroup_subsys_state *css = cfe->css;
- if (cft->write)
- return cft->write(css, cft, file, buf, nbytes, ppos);
if (cft->write_u64 || cft->write_s64)
return cgroup_write_X64(css, cft, file, buf, nbytes, ppos);
if (cft->write_string)
@@ -2366,8 +2364,6 @@
struct cftype *cft = __d_cft(file->f_dentry);
struct cgroup_subsys_state *css = cfe->css;
- if (cft->read)
- return cft->read(css, cft, file, buf, nbytes, ppos);
if (cft->read_u64)
return cgroup_read_u64(css, cft, file, buf, nbytes, ppos);
if (cft->read_s64)
@@ -2380,25 +2376,12 @@
* supports string->u64 maps, but can be extended in future.
*/
-static int cgroup_map_add(struct cgroup_map_cb *cb, const char *key, u64 value)
-{
- struct seq_file *sf = cb->state;
- return seq_printf(sf, "%s %llu\n", key, (unsigned long long)value);
-}
-
static int cgroup_seqfile_show(struct seq_file *m, void *arg)
{
struct cfent *cfe = m->private;
struct cftype *cft = cfe->type;
struct cgroup_subsys_state *css = cfe->css;
- if (cft->read_map) {
- struct cgroup_map_cb cb = {
- .fill = cgroup_map_add,
- .state = m,
- };
- return cft->read_map(css, cft, &cb);
- }
return cft->read_seq_string(css, cft, m);
}
@@ -2444,7 +2427,7 @@
WARN_ON_ONCE(cfe->css && cfe->css != css);
cfe->css = css;
- if (cft->read_map || cft->read_seq_string) {
+ if (cft->read_seq_string) {
file->f_op = &cgroup_seqfile_operations;
err = single_open(file, cgroup_seqfile_show, cfe);
} else if (cft->open) {
@@ -2658,12 +2641,11 @@
if (cft->mode)
return cft->mode;
- if (cft->read || cft->read_u64 || cft->read_s64 ||
- cft->read_map || cft->read_seq_string)
+ if (cft->read_u64 || cft->read_s64 || cft->read_seq_string)
mode |= S_IRUGO;
- if (cft->write || cft->write_u64 || cft->write_s64 ||
- cft->write_string || cft->trigger)
+ if (cft->write_u64 || cft->write_s64 || cft->write_string ||
+ cft->trigger)
mode |= S_IWUSR;
return mode;