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-rw-r--r--block/blk-cgroup.c2
-rw-r--r--include/linux/cgroup.h8
-rw-r--r--kernel/cgroup.c78
3 files changed, 51 insertions, 37 deletions
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 79fd9f4fadb7..34063739745b 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1128,7 +1128,7 @@ void blkcg_policy_unregister(struct blkcg_policy *pol)
/* kill the intf files first */
if (pol->cftypes)
- cgroup_rm_cftypes(&blkio_subsys, pol->cftypes);
+ cgroup_rm_cftypes(pol->cftypes);
/* unregister and update blkgs */
blkcg_policy[pol->plid] = NULL;
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 9c2b9dd9121d..5db8138a0482 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -429,6 +429,12 @@ struct cftype {
/* CFTYPE_* flags */
unsigned int flags;
+ /*
+ * The subsys this file belongs to. Initialized automatically
+ * during registration. NULL for cgroup core files.
+ */
+ struct cgroup_subsys *ss;
+
int (*open)(struct inode *inode, struct file *file);
ssize_t (*read)(struct cgroup *cgrp, struct cftype *cft,
struct file *file,
@@ -542,7 +548,7 @@ static inline const char *cgroup_name(const struct cgroup *cgrp)
}
int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
-int cgroup_rm_cftypes(struct cgroup_subsys *ss, struct cftype *cfts);
+int cgroup_rm_cftypes(struct cftype *cfts);
bool cgroup_is_descendant(struct cgroup *cgrp, struct cgroup *ancestor);
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 271d9a5cde5f..c4bc8dac3b1d 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -219,8 +219,8 @@ static struct cftype cgroup_base_files[];
static void cgroup_offline_fn(struct work_struct *work);
static int cgroup_destroy_locked(struct cgroup *cgrp);
-static int cgroup_addrm_files(struct cgroup *cgrp, struct cgroup_subsys *subsys,
- struct cftype cfts[], bool is_add);
+static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
+ bool is_add);
/* convenient tests for these bits */
static inline bool cgroup_is_dead(const struct cgroup *cgrp)
@@ -974,7 +974,7 @@ static void cgroup_clear_dir(struct cgroup *cgrp, unsigned long subsys_mask)
if (!test_bit(i, &subsys_mask))
continue;
list_for_each_entry(set, &ss->cftsets, node)
- cgroup_addrm_files(cgrp, NULL, set->cfts, false);
+ cgroup_addrm_files(cgrp, set->cfts, false);
}
}
@@ -1623,7 +1623,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
*/
cred = override_creds(&init_cred);
- ret = cgroup_addrm_files(root_cgrp, NULL, cgroup_base_files, true);
+ ret = cgroup_addrm_files(root_cgrp, cgroup_base_files, true);
if (ret)
goto rm_base_files;
@@ -1681,7 +1681,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
rm_base_files:
free_cgrp_cset_links(&tmp_links);
- cgroup_addrm_files(&root->top_cgroup, NULL, cgroup_base_files, false);
+ cgroup_addrm_files(&root->top_cgroup, cgroup_base_files, false);
revert_creds(cred);
unlock_drop:
cgroup_exit_root_id(root);
@@ -2694,8 +2694,7 @@ static umode_t cgroup_file_mode(const struct cftype *cft)
return mode;
}
-static int cgroup_add_file(struct cgroup *cgrp, struct cgroup_subsys *subsys,
- struct cftype *cft)
+static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft)
{
struct dentry *dir = cgrp->dentry;
struct cgroup *parent = __d_cgrp(dir);
@@ -2705,8 +2704,8 @@ static int cgroup_add_file(struct cgroup *cgrp, struct cgroup_subsys *subsys,
umode_t mode;
char name[MAX_CGROUP_TYPE_NAMELEN + MAX_CFTYPE_NAME + 2] = { 0 };
- if (subsys && !(cgrp->root->flags & CGRP_ROOT_NOPREFIX)) {
- strcpy(name, subsys->name);
+ if (cft->ss && !(cgrp->root->flags & CGRP_ROOT_NOPREFIX)) {
+ strcpy(name, cft->ss->name);
strcat(name, ".");
}
strcat(name, cft->name);
@@ -2743,17 +2742,16 @@ out:
/**
* cgroup_addrm_files - add or remove files to a cgroup directory
* @cgrp: the target cgroup
- * @subsys: the subsystem of files to be added
* @cfts: array of cftypes to be added
* @is_add: whether to add or remove
*
* Depending on @is_add, add or remove files defined by @cfts on @cgrp.
- * All @cfts should belong to @subsys. For removals, this function never
- * fails. If addition fails, this function doesn't remove files already
- * added. The caller is responsible for cleaning up.
+ * For removals, this function never fails. If addition fails, this
+ * function doesn't remove files already added. The caller is responsible
+ * for cleaning up.
*/
-static int cgroup_addrm_files(struct cgroup *cgrp, struct cgroup_subsys *subsys,
- struct cftype cfts[], bool is_add)
+static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[],
+ bool is_add)
{
struct cftype *cft;
int ret;
@@ -2771,7 +2769,7 @@ static int cgroup_addrm_files(struct cgroup *cgrp, struct cgroup_subsys *subsys,
continue;
if (is_add) {
- ret = cgroup_add_file(cgrp, subsys, cft);
+ ret = cgroup_add_file(cgrp, cft);
if (ret) {
pr_warn("cgroup_addrm_files: failed to add %s, err=%d\n",
cft->name, ret);
@@ -2796,11 +2794,11 @@ static void cgroup_cfts_prepare(void)
mutex_lock(&cgroup_mutex);
}
-static int cgroup_cfts_commit(struct cgroup_subsys *ss,
- struct cftype *cfts, bool is_add)
+static int cgroup_cfts_commit(struct cftype *cfts, bool is_add)
__releases(&cgroup_mutex)
{
LIST_HEAD(pending);
+ struct cgroup_subsys *ss = cfts[0].ss;
struct cgroup *cgrp, *root = &ss->root->top_cgroup;
struct super_block *sb = ss->root->sb;
struct dentry *prev = NULL;
@@ -2828,7 +2826,7 @@ static int cgroup_cfts_commit(struct cgroup_subsys *ss,
inode = root->dentry->d_inode;
mutex_lock(&inode->i_mutex);
mutex_lock(&cgroup_mutex);
- ret = cgroup_addrm_files(root, ss, cfts, is_add);
+ ret = cgroup_addrm_files(root, cfts, is_add);
mutex_unlock(&cgroup_mutex);
mutex_unlock(&inode->i_mutex);
@@ -2851,7 +2849,7 @@ static int cgroup_cfts_commit(struct cgroup_subsys *ss,
mutex_lock(&inode->i_mutex);
mutex_lock(&cgroup_mutex);
if (cgrp->serial_nr < update_before && !cgroup_is_dead(cgrp))
- ret = cgroup_addrm_files(cgrp, ss, cfts, is_add);
+ ret = cgroup_addrm_files(cgrp, cfts, is_add);
mutex_unlock(&cgroup_mutex);
mutex_unlock(&inode->i_mutex);
@@ -2883,51 +2881,56 @@ out_deact:
int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
{
struct cftype_set *set;
+ struct cftype *cft;
int ret;
set = kzalloc(sizeof(*set), GFP_KERNEL);
if (!set)
return -ENOMEM;
+ for (cft = cfts; cft->name[0] != '\0'; cft++)
+ cft->ss = ss;
+
cgroup_cfts_prepare();
set->cfts = cfts;
list_add_tail(&set->node, &ss->cftsets);
- ret = cgroup_cfts_commit(ss, cfts, true);
+ ret = cgroup_cfts_commit(cfts, true);
if (ret)
- cgroup_rm_cftypes(ss, cfts);
+ cgroup_rm_cftypes(cfts);
return ret;
}
EXPORT_SYMBOL_GPL(cgroup_add_cftypes);
/**
* cgroup_rm_cftypes - remove an array of cftypes from a subsystem
- * @ss: target cgroup subsystem
* @cfts: zero-length name terminated array of cftypes
*
- * Unregister @cfts from @ss. Files described by @cfts are removed from
- * all existing cgroups to which @ss is attached and all future cgroups
- * won't have them either. This function can be called anytime whether @ss
- * is attached or not.
+ * Unregister @cfts. Files described by @cfts are removed from all
+ * existing cgroups and all future cgroups won't have them either. This
+ * function can be called anytime whether @cfts' subsys is attached or not.
*
* Returns 0 on successful unregistration, -ENOENT if @cfts is not
- * registered with @ss.
+ * registered.
*/
-int cgroup_rm_cftypes(struct cgroup_subsys *ss, struct cftype *cfts)
+int cgroup_rm_cftypes(struct cftype *cfts)
{
struct cftype_set *set;
+ if (!cfts || !cfts[0].ss)
+ return -ENOENT;
+
cgroup_cfts_prepare();
- list_for_each_entry(set, &ss->cftsets, node) {
+ list_for_each_entry(set, &cfts[0].ss->cftsets, node) {
if (set->cfts == cfts) {
list_del(&set->node);
kfree(set);
- cgroup_cfts_commit(ss, cfts, false);
+ cgroup_cfts_commit(cfts, false);
return 0;
}
}
- cgroup_cfts_commit(ss, NULL, false);
+ cgroup_cfts_commit(NULL, false);
return -ENOENT;
}
@@ -4148,7 +4151,7 @@ static int cgroup_populate_dir(struct cgroup *cgrp, unsigned long subsys_mask)
continue;
list_for_each_entry(set, &ss->cftsets, node) {
- ret = cgroup_addrm_files(cgrp, ss, set->cfts, true);
+ ret = cgroup_addrm_files(cgrp, set->cfts, true);
if (ret < 0)
goto err;
}
@@ -4377,7 +4380,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
idr_replace(&root->cgroup_idr, cgrp, cgrp->id);
- err = cgroup_addrm_files(cgrp, NULL, cgroup_base_files, true);
+ err = cgroup_addrm_files(cgrp, cgroup_base_files, true);
if (err)
goto err_destroy;
@@ -4538,7 +4541,7 @@ static int cgroup_destroy_locked(struct cgroup *cgrp)
* but we aren't quite done with @cgrp yet, so hold onto it.
*/
cgroup_clear_dir(cgrp, cgrp->root->subsys_mask);
- cgroup_addrm_files(cgrp, NULL, cgroup_base_files, false);
+ cgroup_addrm_files(cgrp, cgroup_base_files, false);
dget(d);
cgroup_d_remove_dir(d);
@@ -4632,6 +4635,11 @@ static void __init_or_module cgroup_init_cftsets(struct cgroup_subsys *ss)
* deregistration.
*/
if (ss->base_cftypes) {
+ struct cftype *cft;
+
+ for (cft = ss->base_cftypes; cft->name[0] != '\0'; cft++)
+ cft->ss = ss;
+
ss->base_cftset.cfts = ss->base_cftypes;
list_add_tail(&ss->base_cftset.node, &ss->cftsets);
}
generated by cgit v1.2.3 (git 2.0.4) at 2024-07-06 01:16:04 +0000