From 6e0755b08dd6a3b5260fafc6969268c2ba261300 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 5 Dec 2013 12:28:03 -0500 Subject: [PATCH] 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 Acked-by: Li Zefan --- include/linux/cgroup.h | 25 ------------------------- kernel/cgroup.c | 26 ++++---------------------- 2 files changed, 4 insertions(+), 47 deletions(-) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 50d8cc3..53e11da 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -387,16 +387,6 @@ struct css_set { }; /* - * cgroup_map_cb is an abstract callback API for reporting map-valued - * control files - */ - -struct cgroup_map_cb { - int (*fill)(struct cgroup_map_cb *cb, const char *key, u64 value); - void *state; -}; - -/* * struct cftype: handler definitions for cgroup control files * * When reading/writing to a file: @@ -444,9 +434,6 @@ struct cftype { struct cgroup_subsys *ss; int (*open)(struct inode *inode, struct file *file); - ssize_t (*read)(struct cgroup_subsys_state *css, struct cftype *cft, - struct file *file, - char __user *buf, size_t nbytes, loff_t *ppos); /* * read_u64() is a shortcut for the common case of returning a * single integer. Use it in place of read() @@ -457,24 +444,12 @@ struct cftype { */ s64 (*read_s64)(struct cgroup_subsys_state *css, struct cftype *cft); /* - * read_map() is used for defining a map of key/value - * pairs. It should call cb->fill(cb, key, value) for each - * entry. The key/value pairs (and their ordering) should not - * change between reboots. - */ - int (*read_map)(struct cgroup_subsys_state *css, struct cftype *cft, - struct cgroup_map_cb *cb); - /* * read_seq_string() is used for outputting a simple sequence * using seqfile. */ int (*read_seq_string)(struct cgroup_subsys_state *css, struct cftype *cft, struct seq_file *m); - ssize_t (*write)(struct cgroup_subsys_state *css, struct cftype *cft, - struct file *file, - const char __user *buf, size_t nbytes, loff_t *ppos); - /* * write_u64() is a shortcut for the common case of accepting * a single integer (as parsed by simple_strtoull) from 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 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf, 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 @@ static ssize_t cgroup_file_read(struct file *file, char __user *buf, 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 @@ static ssize_t cgroup_file_read(struct file *file, char __user *buf, * 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 @@ static int cgroup_file_open(struct inode *inode, struct file *file) 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 @@ static umode_t cgroup_file_mode(const struct cftype *cft) 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; -- 2.7.4