diff options
Diffstat (limited to 'fs/configfs')
| -rw-r--r-- | fs/configfs/Kconfig | 11 | ||||
| -rw-r--r-- | fs/configfs/dir.c | 59 | ||||
| -rw-r--r-- | fs/configfs/inode.c | 3 |
3 files changed, 70 insertions, 3 deletions
diff --git a/fs/configfs/Kconfig b/fs/configfs/Kconfig new file mode 100644 index 0000000..13587cc --- /dev/null +++ b/fs/configfs/Kconfig @@ -0,0 +1,11 @@ +config CONFIGFS_FS + tristate "Userspace-driven configuration filesystem" + depends on SYSFS + help + configfs is a ram-based filesystem that provides the converse + of sysfs's functionality. Where sysfs is a filesystem-based + view of kernel objects, configfs is a filesystem-based manager + of kernel objects, or config_items. + + Both sysfs and configfs can and should exist together on the + same system. One is not a replacement for the other. diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index 8e93341..9c23583 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -553,12 +553,24 @@ static void detach_groups(struct config_group *group) child = sd->s_dentry; + /* + * Note: we hide this from lockdep since we have no way + * to teach lockdep about recursive + * I_MUTEX_PARENT -> I_MUTEX_CHILD patterns along a path + * in an inode tree, which are valid as soon as + * I_MUTEX_PARENT -> I_MUTEX_CHILD is valid from a + * parent inode to one of its children. + */ + lockdep_off(); mutex_lock(&child->d_inode->i_mutex); + lockdep_on(); configfs_detach_group(sd->s_element); child->d_inode->i_flags |= S_DEAD; + lockdep_off(); mutex_unlock(&child->d_inode->i_mutex); + lockdep_on(); d_delete(child); dput(child); @@ -748,11 +760,22 @@ static int configfs_attach_item(struct config_item *parent_item, * We are going to remove an inode and its dentry but * the VFS may already have hit and used them. Thus, * we must lock them as rmdir() would. + * + * Note: we hide this from lockdep since we have no way + * to teach lockdep about recursive + * I_MUTEX_PARENT -> I_MUTEX_CHILD patterns along a path + * in an inode tree, which are valid as soon as + * I_MUTEX_PARENT -> I_MUTEX_CHILD is valid from a + * parent inode to one of its children. */ + lockdep_off(); mutex_lock(&dentry->d_inode->i_mutex); + lockdep_on(); configfs_remove_dir(item); dentry->d_inode->i_flags |= S_DEAD; + lockdep_off(); mutex_unlock(&dentry->d_inode->i_mutex); + lockdep_on(); d_delete(dentry); } } @@ -787,14 +810,25 @@ static int configfs_attach_group(struct config_item *parent_item, * * We must also lock the inode to remove it safely in case of * error, as rmdir() would. + * + * Note: we hide this from lockdep since we have no way + * to teach lockdep about recursive + * I_MUTEX_PARENT -> I_MUTEX_CHILD patterns along a path + * in an inode tree, which are valid as soon as + * I_MUTEX_PARENT -> I_MUTEX_CHILD is valid from a + * parent inode to one of its children. */ + lockdep_off(); mutex_lock_nested(&dentry->d_inode->i_mutex, I_MUTEX_CHILD); + lockdep_on(); ret = populate_groups(to_config_group(item)); if (ret) { configfs_detach_item(item); dentry->d_inode->i_flags |= S_DEAD; } + lockdep_off(); mutex_unlock(&dentry->d_inode->i_mutex); + lockdep_on(); if (ret) d_delete(dentry); } @@ -956,7 +990,17 @@ static int configfs_depend_prep(struct dentry *origin, BUG_ON(!origin || !sd); /* Lock this guy on the way down */ + /* + * Note: we hide this from lockdep since we have no way + * to teach lockdep about recursive + * I_MUTEX_PARENT -> I_MUTEX_CHILD patterns along a path + * in an inode tree, which are valid as soon as + * I_MUTEX_PARENT -> I_MUTEX_CHILD is valid from a + * parent inode to one of its children. + */ + lockdep_off(); mutex_lock(&sd->s_dentry->d_inode->i_mutex); + lockdep_on(); if (sd->s_element == target) /* Boo-yah */ goto out; @@ -970,7 +1014,9 @@ static int configfs_depend_prep(struct dentry *origin, } /* We looped all our children and didn't find target */ + lockdep_off(); mutex_unlock(&sd->s_dentry->d_inode->i_mutex); + lockdep_on(); ret = -ENOENT; out: @@ -990,11 +1036,16 @@ static void configfs_depend_rollback(struct dentry *origin, struct dentry *dentry = item->ci_dentry; while (dentry != origin) { + /* See comments in configfs_depend_prep() */ + lockdep_off(); mutex_unlock(&dentry->d_inode->i_mutex); + lockdep_on(); dentry = dentry->d_parent; } + lockdep_off(); mutex_unlock(&origin->d_inode->i_mutex); + lockdep_on(); } int configfs_depend_item(struct configfs_subsystem *subsys, @@ -1329,8 +1380,16 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry) } /* Wait until the racing operation terminates */ + /* + * Note: we hide this from lockdep since we are locked + * with subclass I_MUTEX_NORMAL from vfs_rmdir() (why + * not I_MUTEX_CHILD?), and I_MUTEX_XATTR or + * I_MUTEX_QUOTA are not relevant for the locked inode. + */ + lockdep_off(); mutex_lock(wait_mutex); mutex_unlock(wait_mutex); + lockdep_on(); } } while (ret == -EAGAIN); diff --git a/fs/configfs/inode.c b/fs/configfs/inode.c index 4803ccc..5d349d3 100644 --- a/fs/configfs/inode.c +++ b/fs/configfs/inode.c @@ -117,8 +117,6 @@ int configfs_setattr(struct dentry * dentry, struct iattr * iattr) static inline void set_default_inode_attr(struct inode * inode, mode_t mode) { inode->i_mode = mode; - inode->i_uid = 0; - inode->i_gid = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; } @@ -136,7 +134,6 @@ struct inode * configfs_new_inode(mode_t mode, struct configfs_dirent * sd) { struct inode * inode = new_inode(configfs_sb); if (inode) { - inode->i_blocks = 0; inode->i_mapping->a_ops = &configfs_aops; inode->i_mapping->backing_dev_info = &configfs_backing_dev_info; inode->i_op = &configfs_inode_operations; |