diff options
Diffstat (limited to 'kernel/cgroup.c')
| -rw-r--r-- | kernel/cgroup.c | 36 |
1 files changed, 24 insertions, 12 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 7d207414f2c7..b0fee0c61445 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -591,6 +591,7 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode) /* is dentry a directory ? if so, kfree() associated cgroup */ if (S_ISDIR(inode->i_mode)) { struct cgroup *cgrp = dentry->d_fsdata; + struct cgroup_subsys *ss; BUG_ON(!(cgroup_is_removed(cgrp))); /* It's possible for external users to be holding css * reference counts on a cgroup; css_put() needs to @@ -599,6 +600,23 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode) * queue the cgroup to be handled by the release * agent */ synchronize_rcu(); + + mutex_lock(&cgroup_mutex); + /* + * Release the subsystem state objects. + */ + for_each_subsys(cgrp->root, ss) { + if (cgrp->subsys[ss->subsys_id]) + ss->destroy(ss, cgrp); + } + + cgrp->root->number_of_cgroups--; + mutex_unlock(&cgroup_mutex); + + /* Drop the active superblock reference that we took when we + * created the cgroup */ + deactivate_super(cgrp->root->sb); + kfree(cgrp); } iput(inode); @@ -1330,6 +1348,10 @@ static ssize_t cgroup_common_file_write(struct cgroup *cgrp, mutex_lock(&cgroup_mutex); + /* + * This was already checked for in cgroup_file_write(), but + * check again now we're holding cgroup_mutex. + */ if (cgroup_is_removed(cgrp)) { retval = -ENODEV; goto out2; @@ -1370,7 +1392,7 @@ static ssize_t cgroup_file_write(struct file *file, const char __user *buf, struct cftype *cft = __d_cft(file->f_dentry); struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent); - if (!cft) + if (!cft || cgroup_is_removed(cgrp)) return -ENODEV; if (cft->write) return cft->write(cgrp, cft, file, buf, nbytes, ppos); @@ -1440,7 +1462,7 @@ static ssize_t cgroup_file_read(struct file *file, char __user *buf, struct cftype *cft = __d_cft(file->f_dentry); struct cgroup *cgrp = __d_cgrp(file->f_dentry->d_parent); - if (!cft) + if (!cft || cgroup_is_removed(cgrp)) return -ENODEV; if (cft->read) @@ -2120,7 +2142,6 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) struct cgroup *cgrp = dentry->d_fsdata; struct dentry *d; struct cgroup *parent; - struct cgroup_subsys *ss; struct super_block *sb; struct cgroupfs_root *root; @@ -2145,11 +2166,6 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) return -EBUSY; } - for_each_subsys(root, ss) { - if (cgrp->subsys[ss->subsys_id]) - ss->destroy(ss, cgrp); - } - spin_lock(&release_list_lock); set_bit(CGRP_REMOVED, &cgrp->flags); if (!list_empty(&cgrp->release_list)) @@ -2164,15 +2180,11 @@ static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry) cgroup_d_remove_dir(d); dput(d); - root->number_of_cgroups--; set_bit(CGRP_RELEASABLE, &parent->flags); check_for_release(parent); mutex_unlock(&cgroup_mutex); - /* Drop the active superblock reference that we took when we - * created the cgroup */ - deactivate_super(sb); return 0; } |