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| author | Tejun Heo <tj@kernel.org> | 2016-12-27 14:49:03 -0500 |
|---|---|---|
| committer | Tejun Heo <tj@kernel.org> | 2016-12-27 14:49:03 -0500 |
| commit | e90cbebc3fa5caea4c8bfeb0d0157a0cee53efc7 (patch) | |
| tree | 86c2bdab65cfde9766a6779979bd3836e71bdd74 | |
| parent | 0e67db2f9fe91937e798e3d7d22c50a8438187e1 (diff) | |
| download | linux-e90cbebc3fa5caea4c8bfeb0d0157a0cee53efc7.tar.gz linux-e90cbebc3fa5caea4c8bfeb0d0157a0cee53efc7.tar.bz2 linux-e90cbebc3fa5caea4c8bfeb0d0157a0cee53efc7.zip | |
cgroup add cftype->open/release() callbacks
Pipe the newly added kernfs->open/release() callbacks through cftype.
While at it, as cleanup operations now can be performed from
->release() instead of ->seq_stop(), make the latter optional.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Acked-by: Zefan Li <lizefan@huawei.com>
| -rw-r--r-- | include/linux/cgroup-defs.h | 3 | ||||
| -rw-r--r-- | kernel/cgroup.c | 24 |
2 files changed, 26 insertions, 1 deletions
diff --git a/include/linux/cgroup-defs.h b/include/linux/cgroup-defs.h index 861b4677fc5b..8a916dc96e84 100644 --- a/include/linux/cgroup-defs.h +++ b/include/linux/cgroup-defs.h @@ -388,6 +388,9 @@ struct cftype { struct list_head node; /* anchored at ss->cfts */ struct kernfs_ops *kf_ops; + int (*open)(struct kernfs_open_file *of); + void (*release)(struct kernfs_open_file *of); + /* * read_u64() is a shortcut for the common case of returning a * single integer. Use it in place of read() diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 2ee9ec3051b2..87167e40c4fa 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -3503,6 +3503,23 @@ static int cgroup_events_show(struct seq_file *seq, void *v) return 0; } +static int cgroup_file_open(struct kernfs_open_file *of) +{ + struct cftype *cft = of->kn->priv; + + if (cft->open) + return cft->open(of); + return 0; +} + +static void cgroup_file_release(struct kernfs_open_file *of) +{ + struct cftype *cft = of->kn->priv; + + if (cft->release) + cft->release(of); +} + static ssize_t cgroup_file_write(struct kernfs_open_file *of, char *buf, size_t nbytes, loff_t off) { @@ -3553,7 +3570,8 @@ static void *cgroup_seqfile_next(struct seq_file *seq, void *v, loff_t *ppos) static void cgroup_seqfile_stop(struct seq_file *seq, void *v) { - seq_cft(seq)->seq_stop(seq, v); + if (seq_cft(seq)->seq_stop) + seq_cft(seq)->seq_stop(seq, v); } static int cgroup_seqfile_show(struct seq_file *m, void *arg) @@ -3575,12 +3593,16 @@ static int cgroup_seqfile_show(struct seq_file *m, void *arg) static struct kernfs_ops cgroup_kf_single_ops = { .atomic_write_len = PAGE_SIZE, + .open = cgroup_file_open, + .release = cgroup_file_release, .write = cgroup_file_write, .seq_show = cgroup_seqfile_show, }; static struct kernfs_ops cgroup_kf_ops = { .atomic_write_len = PAGE_SIZE, + .open = cgroup_file_open, + .release = cgroup_file_release, .write = cgroup_file_write, .seq_start = cgroup_seqfile_start, .seq_next = cgroup_seqfile_next, |