While shadow directories appear to be a good idea, the current scheme of controlling their creation and destruction outside of sysfs appears to be a locking and maintenance nightmare in the face of sysfs directories dynamically coming and going. Which can now occur for directories containing network devices when CONFIG_SYSFS_DEPRECATED is not set. This patch removes everything from the initial shadow directory support that allowed the shadow directory creation to be controlled at a higher level. So except for a few bits of sysfs_rename_dir everything from commit b592fcfe7f06c15ec11774b5be7ce0de3aa86e73 is now gone. Signed-off-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> --- These patches are against 2.6.22-rc4-mm2 Hopefully that is new enough to catch all of the in flight sysfs patches. fs/sysfs/dir.c | 172 ++++++++++------------------------------------- fs/sysfs/group.c | 1 - fs/sysfs/inode.c | 10 --- fs/sysfs/mount.c | 2 +- fs/sysfs/sysfs.h | 6 -- include/linux/kobject.h | 4 - include/linux/sysfs.h | 24 +------ lib/kobject.c | 44 ++---------- 8 files changed, 48 insertions(+), 215 deletions(-) diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index b4074ad..b1da4fc 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -415,10 +415,9 @@ int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d) /** * sysfs_create_dir - create a directory for an object. * @kobj: object we're creating directory for. - * @shadow_parent: parent parent object. */ -int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent) +int sysfs_create_dir(struct kobject * kobj) { struct dentry * dentry = NULL; struct dentry * parent; @@ -426,9 +425,7 @@ int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent) BUG_ON(!kobj); - if (shadow_parent) - parent = shadow_parent; - else if (kobj->parent) + if (kobj->parent) parent = kobj->parent->dentry; else if (sysfs_mount && sysfs_mount->mnt_sb) parent = sysfs_mount->mnt_sb->s_root; @@ -516,12 +513,26 @@ void sysfs_remove_subdir(struct dentry * d) } -static void __sysfs_remove_dir(struct dentry *dentry) +/** + * sysfs_remove_dir - remove an object's directory. + * @kobj: object. + * + * The only thing special about this is that we remove any files in + * the directory before we remove the directory, and we've inlined + * what used to be sysfs_rmdir() below, instead of calling separately. + */ + +void sysfs_remove_dir(struct kobject * kobj) { + struct dentry *dentry = kobj->dentry; struct sysfs_dirent *removed = NULL; struct sysfs_dirent *parent_sd; struct sysfs_dirent **pos; + spin_lock(&kobj_sysfs_assoc_lock); + kobj->dentry = NULL; + spin_unlock(&kobj_sysfs_assoc_lock); + if (!dentry) return; @@ -555,55 +566,35 @@ static void __sysfs_remove_dir(struct dentry *dentry) remove_dir(dentry); } -/** - * sysfs_remove_dir - remove an object's directory. - * @kobj: object. - * - * The only thing special about this is that we remove any files in - * the directory before we remove the directory, and we've inlined - * what used to be sysfs_rmdir() below, instead of calling separately. - */ - -void sysfs_remove_dir(struct kobject * kobj) -{ - struct dentry *d = kobj->dentry; - - spin_lock(&kobj_sysfs_assoc_lock); - kobj->dentry = NULL; - spin_unlock(&kobj_sysfs_assoc_lock); - - __sysfs_remove_dir(d); -} - -int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, - const char *new_name) +int sysfs_rename_dir(struct kobject * kobj, const char *new_name) { - struct sysfs_dirent *sd = kobj->dentry->d_fsdata; - struct sysfs_dirent *parent_sd = new_parent->d_fsdata; - struct dentry *new_dentry; + struct sysfs_dirent *sd; + struct sysfs_dirent *parent_sd; + struct inode *inode; + struct dentry *new_dentry, *parent; char *dup_name; int error; - if (!new_parent) - return -EFAULT; + if (!kobj->parent) + return -EINVAL; + + parent = dget(kobj->dentry->d_parent); + inode = parent->d_inode; + + sd = kobj->dentry->d_fsdata; down_write(&sysfs_rename_sem); - mutex_lock(&new_parent->d_inode->i_mutex); + mutex_lock(&inode->i_mutex); - new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name)); + parent_sd = parent->d_fsdata; + new_dentry = lookup_one_len(new_name, parent_sd->s_dentry, strlen(new_name)); if (IS_ERR(new_dentry)) { error = PTR_ERR(new_dentry); goto out_unlock; } - /* By allowing two different directories with the same - * d_parent we allow this routine to move between different - * shadows of the same directory - */ error = -EINVAL; - if (kobj->dentry->d_parent->d_inode != new_parent->d_inode || - new_dentry->d_parent->d_inode != new_parent->d_inode || - new_dentry == kobj->dentry) + if (new_dentry == kobj->dentry) goto out_dput; error = -EEXIST; @@ -643,8 +634,11 @@ int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, out_dput: dput(new_dentry); out_unlock: - mutex_unlock(&new_parent->d_inode->i_mutex); + mutex_unlock(&inode->i_mutex); up_write(&sysfs_rename_sem); + + dput(parent); + return error; } @@ -837,98 +831,6 @@ static loff_t sysfs_dir_lseek(struct file * file, loff_t offset, int origin) return offset; } - -/** - * sysfs_make_shadowed_dir - Setup so a directory can be shadowed - * @kobj: object we're creating shadow of. - */ - -int sysfs_make_shadowed_dir(struct kobject *kobj, - void * (*follow_link)(struct dentry *, struct nameidata *)) -{ - struct inode *inode; - struct inode_operations *i_op; - - inode = kobj->dentry->d_inode; - if (inode->i_op != &sysfs_dir_inode_operations) - return -EINVAL; - - i_op = kmalloc(sizeof(*i_op), GFP_KERNEL); - if (!i_op) - return -ENOMEM; - - memcpy(i_op, &sysfs_dir_inode_operations, sizeof(*i_op)); - i_op->follow_link = follow_link; - - /* Locking of inode->i_op? - * Since setting i_op is a single word write and they - * are atomic we should be ok here. - */ - inode->i_op = i_op; - return 0; -} - -/** - * sysfs_create_shadow_dir - create a shadow directory for an object. - * @kobj: object we're creating directory for. - * - * sysfs_make_shadowed_dir must already have been called on this - * directory. - */ - -struct dentry *sysfs_create_shadow_dir(struct kobject *kobj) -{ - struct dentry *dir = kobj->dentry; - struct inode *inode = dir->d_inode; - struct dentry *parent = dir->d_parent; - struct sysfs_dirent *parent_sd = parent->d_fsdata; - struct dentry *shadow; - struct sysfs_dirent *sd; - - shadow = ERR_PTR(-EINVAL); - if (!sysfs_is_shadowed_inode(inode)) - goto out; - - shadow = d_alloc(parent, &dir->d_name); - if (!shadow) - goto nomem; - - sd = sysfs_new_dirent("_SHADOW_", inode->i_mode, SYSFS_DIR); - if (!sd) - goto nomem; - sd->s_elem.dir.kobj = kobj; - /* point to parent_sd but don't attach to it */ - sd->s_parent = sysfs_get(parent_sd); - sysfs_attach_dirent(sd, NULL, shadow); - - d_instantiate(shadow, igrab(inode)); - inc_nlink(inode); - inc_nlink(parent->d_inode); - - dget(shadow); /* Extra count - pin the dentry in core */ - -out: - return shadow; -nomem: - dput(shadow); - shadow = ERR_PTR(-ENOMEM); - goto out; -} - -/** - * sysfs_remove_shadow_dir - remove an object's directory. - * @shadow: dentry of shadow directory - * - * The only thing special about this is that we remove any files in - * the directory before we remove the directory, and we've inlined - * what used to be sysfs_rmdir() below, instead of calling separately. - */ - -void sysfs_remove_shadow_dir(struct dentry *shadow) -{ - __sysfs_remove_dir(shadow); -} - const struct file_operations sysfs_dir_operations = { .open = sysfs_dir_open, .release = sysfs_dir_close, diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c index 52eed2a..82e0f55 100644 --- a/fs/sysfs/group.c +++ b/fs/sysfs/group.c @@ -13,7 +13,6 @@ #include <linux/dcache.h> #include <linux/namei.h> #include <linux/err.h> -#include <linux/fs.h> #include <asm/semaphore.h> #include "sysfs.h" diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c index b1a4527..8181c49 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -34,16 +34,6 @@ static const struct inode_operations sysfs_inode_operations ={ .setattr = sysfs_setattr, }; -void sysfs_delete_inode(struct inode *inode) -{ - /* Free the shadowed directory inode operations */ - if (sysfs_is_shadowed_inode(inode)) { - kfree(inode->i_op); - inode->i_op = NULL; - } - return generic_delete_inode(inode); -} - int sysfs_setattr(struct dentry * dentry, struct iattr * iattr) { struct inode * inode = dentry->d_inode; diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 4be9593..c8126ab 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -21,7 +21,7 @@ struct kmem_cache *sysfs_dir_cachep; static const struct super_operations sysfs_ops = { .statfs = simple_statfs, - .drop_inode = sysfs_delete_inode, + .drop_inode = generic_delete_inode, }; static struct sysfs_dirent sysfs_root = { diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index 6f8aaf3..6258462 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -53,7 +53,6 @@ extern struct sysfs_dirent *sysfs_get_active_two(struct sysfs_dirent *sd); extern void sysfs_put_active_two(struct sysfs_dirent *sd); extern void sysfs_deactivate(struct sysfs_dirent *sd); -extern void sysfs_delete_inode(struct inode *inode); extern void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode); extern struct inode * sysfs_get_inode(struct sysfs_dirent *sd); extern void sysfs_instantiate(struct dentry *dentry, struct inode *inode); @@ -100,8 +99,3 @@ static inline void sysfs_put(struct sysfs_dirent * sd) if (sd && atomic_dec_and_test(&sd->s_count)) release_sysfs_dirent(sd); } - -static inline int sysfs_is_shadowed_inode(struct inode *inode) -{ - return S_ISDIR(inode->i_mode) && inode->i_op->follow_link; -} diff --git a/include/linux/kobject.h b/include/linux/kobject.h index c288e41..4fa5b88 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -71,13 +71,9 @@ extern void kobject_init(struct kobject *); extern void kobject_cleanup(struct kobject *); extern int __must_check kobject_add(struct kobject *); -extern int __must_check kobject_shadow_add(struct kobject *, struct dentry *); extern void kobject_del(struct kobject *); extern int __must_check kobject_rename(struct kobject *, const char *new_name); -extern int __must_check kobject_shadow_rename(struct kobject *kobj, - struct dentry *new_parent, - const char *new_name); extern int __must_check kobject_move(struct kobject *, struct kobject *); extern int __must_check kobject_register(struct kobject *); diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 161e19a..a3fa5b9 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -17,8 +17,6 @@ struct kobject; struct module; -struct nameidata; -struct dentry; /* FIXME * The *owner field is no longer used, but leave around @@ -88,13 +86,13 @@ extern int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *), void *data, struct module *owner); extern int __must_check -sysfs_create_dir(struct kobject *, struct dentry *); +sysfs_create_dir(struct kobject *); extern void sysfs_remove_dir(struct kobject *); extern int __must_check -sysfs_rename_dir(struct kobject *, struct dentry *, const char *new_name); +sysfs_rename_dir(struct kobject *, const char *new_name); extern int __must_check sysfs_move_dir(struct kobject *, struct kobject *); @@ -131,12 +129,6 @@ void sysfs_remove_file_from_group(struct kobject *kobj, void sysfs_notify(struct kobject * k, char *dir, char *attr); - -extern int sysfs_make_shadowed_dir(struct kobject *kobj, - void * (*follow_link)(struct dentry *, struct nameidata *)); -extern struct dentry *sysfs_create_shadow_dir(struct kobject *kobj); -extern void sysfs_remove_shadow_dir(struct dentry *dir); - extern int __must_check sysfs_init(void); #else /* CONFIG_SYSFS */ @@ -147,7 +139,7 @@ static inline int sysfs_schedule_callback(struct kobject *kobj, return -ENOSYS; } -static inline int sysfs_create_dir(struct kobject * k, struct dentry *shadow) +static inline int sysfs_create_dir(struct kobject * k) { return 0; } @@ -157,9 +149,7 @@ static inline void sysfs_remove_dir(struct kobject * k) ; } -static inline int sysfs_rename_dir(struct kobject * k, - struct dentry *new_parent, - const char *new_name) +static inline int sysfs_rename_dir(struct kobject * k, const char *new_name) { return 0; } @@ -234,12 +224,6 @@ static inline void sysfs_notify(struct kobject * k, char *dir, char *attr) { } -static inline int sysfs_make_shadowed_dir(struct kobject *kobj, - void * (*follow_link)(struct dentry *, struct nameidata *)) -{ - return 0; -} - static inline int __must_check sysfs_init(void) { return 0; diff --git a/lib/kobject.c b/lib/kobject.c index cb40a00..738d76f 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -46,11 +46,11 @@ static int populate_dir(struct kobject * kobj) return error; } -static int create_dir(struct kobject * kobj, struct dentry *shadow_parent) +static int create_dir(struct kobject * kobj) { int error = 0; if (kobject_name(kobj)) { - error = sysfs_create_dir(kobj, shadow_parent); + error = sysfs_create_dir(kobj); if (!error) { if ((error = populate_dir(kobj))) sysfs_remove_dir(kobj); @@ -201,12 +201,11 @@ static void unlink(struct kobject * kobj) } /** - * kobject_shadow_add - add an object to the hierarchy. + * kobject_add - add an object to the hierarchy. * @kobj: object. - * @shadow_parent: sysfs directory to add to. */ -int kobject_shadow_add(struct kobject * kobj, struct dentry *shadow_parent) +int kobject_add(struct kobject * kobj) { int error = 0; struct kobject * parent; @@ -238,7 +237,7 @@ int kobject_shadow_add(struct kobject * kobj, struct dentry *shadow_parent) kobj->parent = parent; } - error = create_dir(kobj, shadow_parent); + error = create_dir(kobj); if (error) { /* unlink does the kobject_put() for us */ unlink(kobj); @@ -260,16 +259,6 @@ int kobject_shadow_add(struct kobject * kobj, struct dentry *shadow_parent) } /** - * kobject_add - add an object to the hierarchy. - * @kobj: object. - */ -int kobject_add(struct kobject * kobj) -{ - return kobject_shadow_add(kobj, NULL); -} - - -/** * kobject_register - initialize and add an object. * @kobj: object in question. */ @@ -382,7 +371,7 @@ int kobject_rename(struct kobject * kobj, const char *new_name) /* Note : if we want to send the new name alone, not the full path, * we could probably use kobject_name(kobj); */ - error = sysfs_rename_dir(kobj, kobj->parent->dentry, new_name); + error = sysfs_rename_dir(kobj, new_name); /* This function is mostly/only used for network interface. * Some hotplug package track interfaces by their name and @@ -399,27 +388,6 @@ out: } /** - * kobject_rename - change the name of an object - * @kobj: object in question. - * @new_parent: object's new parent - * @new_name: object's new name - */ - -int kobject_shadow_rename(struct kobject * kobj, struct dentry *new_parent, - const char *new_name) -{ - int error = 0; - - kobj = kobject_get(kobj); - if (!kobj) - return -EINVAL; - error = sysfs_rename_dir(kobj, new_parent, new_name); - kobject_put(kobj); - - return error; -} - -/** * kobject_move - move object to another parent * @kobj: object in question. * @new_parent: object's new parent (can be NULL) -- 1.5.1.1.181.g2de0 _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers