diff options
| -rw-r--r-- | fs/kernfs/dir.c | 44 | ||||
| -rw-r--r-- | fs/sysfs/mount.c | 2 | ||||
| -rw-r--r-- | include/linux/kernfs.h | 21 |
3 files changed, 63 insertions, 4 deletions
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index 42c5b9f23b41..510b5062ef30 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -583,12 +583,13 @@ EXPORT_SYMBOL_GPL(kernfs_find_and_get_ns); /** * kernfs_create_root - create a new kernfs hierarchy + * @kdops: optional directory syscall operations for the hierarchy * @priv: opaque data associated with the new directory * * Returns the root of the new hierarchy on success, ERR_PTR() value on * failure. */ -struct kernfs_root *kernfs_create_root(void *priv) +struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv) { struct kernfs_root *root; struct kernfs_node *kn; @@ -610,6 +611,7 @@ struct kernfs_root *kernfs_create_root(void *priv) kn->priv = priv; kn->dir.root = root; + root->dir_ops = kdops; root->kn = kn; return root; @@ -706,6 +708,42 @@ static struct dentry *kernfs_iop_lookup(struct inode *dir, return ret; } +static int kernfs_iop_mkdir(struct inode *dir, struct dentry *dentry, + umode_t mode) +{ + struct kernfs_node *parent = dir->i_private; + struct kernfs_dir_ops *kdops = kernfs_root(parent)->dir_ops; + + if (!kdops || !kdops->mkdir) + return -EPERM; + + return kdops->mkdir(parent, dentry->d_name.name, mode); +} + +static int kernfs_iop_rmdir(struct inode *dir, struct dentry *dentry) +{ + struct kernfs_node *kn = dentry->d_fsdata; + struct kernfs_dir_ops *kdops = kernfs_root(kn)->dir_ops; + + if (!kdops || !kdops->rmdir) + return -EPERM; + + return kdops->rmdir(kn); +} + +static int kernfs_iop_rename(struct inode *old_dir, struct dentry *old_dentry, + struct inode *new_dir, struct dentry *new_dentry) +{ + struct kernfs_node *kn = old_dentry->d_fsdata; + struct kernfs_node *new_parent = new_dir->i_private; + struct kernfs_dir_ops *kdops = kernfs_root(kn)->dir_ops; + + if (!kdops || !kdops->rename) + return -EPERM; + + return kdops->rename(kn, new_parent, new_dentry->d_name.name); +} + const struct inode_operations kernfs_dir_iops = { .lookup = kernfs_iop_lookup, .permission = kernfs_iop_permission, @@ -715,6 +753,10 @@ const struct inode_operations kernfs_dir_iops = { .removexattr = kernfs_iop_removexattr, .getxattr = kernfs_iop_getxattr, .listxattr = kernfs_iop_listxattr, + + .mkdir = kernfs_iop_mkdir, + .rmdir = kernfs_iop_rmdir, + .rename = kernfs_iop_rename, }; static struct kernfs_node *kernfs_leftmost_descendant(struct kernfs_node *pos) diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 701a56f341c6..6211230814fd 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -62,7 +62,7 @@ int __init sysfs_init(void) { int err; - sysfs_root = kernfs_create_root(NULL); + sysfs_root = kernfs_create_root(NULL, NULL); if (IS_ERR(sysfs_root)) return PTR_ERR(sysfs_root); diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 321ed84ad4ce..d2c439db4efa 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -111,12 +111,27 @@ struct kernfs_node { struct kernfs_iattrs *iattr; }; +/* + * kernfs_dir_ops may be specified on kernfs_create_root() to support + * directory manipulation syscalls. These optional callbacks are invoked + * on the matching syscalls and can perform any kernfs operations which + * don't necessarily have to be the exact operation requested. + */ +struct kernfs_dir_ops { + int (*mkdir)(struct kernfs_node *parent, const char *name, + umode_t mode); + int (*rmdir)(struct kernfs_node *kn); + int (*rename)(struct kernfs_node *kn, struct kernfs_node *new_parent, + const char *new_name); +}; + struct kernfs_root { /* published fields */ struct kernfs_node *kn; /* private fields, do not use outside kernfs proper */ struct ida ino_ida; + struct kernfs_dir_ops *dir_ops; }; struct kernfs_open_file { @@ -206,7 +221,8 @@ struct kernfs_node *kernfs_find_and_get_ns(struct kernfs_node *parent, void kernfs_get(struct kernfs_node *kn); void kernfs_put(struct kernfs_node *kn); -struct kernfs_root *kernfs_create_root(void *priv); +struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops, + void *priv); void kernfs_destroy_root(struct kernfs_root *root); struct kernfs_node *kernfs_create_dir_ns(struct kernfs_node *parent, @@ -255,7 +271,8 @@ kernfs_find_and_get_ns(struct kernfs_node *parent, const char *name, static inline void kernfs_get(struct kernfs_node *kn) { } static inline void kernfs_put(struct kernfs_node *kn) { } -static inline struct kernfs_root *kernfs_create_root(void *priv) +static inline struct kernfs_root * +kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv) { return ERR_PTR(-ENOSYS); } static inline void kernfs_destroy_root(struct kernfs_root *root) { } |