diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/sysfs/dir.c | 207 | ||||
| -rw-r--r-- | fs/sysfs/group.c | 1 | ||||
| -rw-r--r-- | fs/sysfs/inode.c | 10 | ||||
| -rw-r--r-- | fs/sysfs/mount.c | 2 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 5 |
5 files changed, 189 insertions, 36 deletions
diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 9ff04491e3e..9dcdf556c99 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -33,8 +33,7 @@ static struct dentry_operations sysfs_dentry_ops = { /* * Allocates a new sysfs_dirent and links it to the parent sysfs_dirent */ -static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent * parent_sd, - void * element) +static struct sysfs_dirent * __sysfs_new_dirent(void * element) { struct sysfs_dirent * sd; @@ -46,12 +45,28 @@ static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent * parent_sd, atomic_set(&sd->s_count, 1); atomic_set(&sd->s_event, 1); INIT_LIST_HEAD(&sd->s_children); - list_add(&sd->s_sibling, &parent_sd->s_children); + INIT_LIST_HEAD(&sd->s_sibling); sd->s_element = element; return sd; } +static void __sysfs_list_dirent(struct sysfs_dirent *parent_sd, + struct sysfs_dirent *sd) +{ + if (sd) + list_add(&sd->s_sibling, &parent_sd->s_children); +} + +static struct sysfs_dirent * sysfs_new_dirent(struct sysfs_dirent *parent_sd, + void * element) +{ + struct sysfs_dirent *sd; + sd = __sysfs_new_dirent(element); + __sysfs_list_dirent(parent_sd, sd); + return sd; +} + /* * * Return -EEXIST if there is already a sysfs element with the same name for @@ -78,14 +93,14 @@ int sysfs_dirent_exist(struct sysfs_dirent *parent_sd, } -int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, - void * element, umode_t mode, int type) +static struct sysfs_dirent * +__sysfs_make_dirent(struct dentry *dentry, void *element, mode_t mode, int type) { struct sysfs_dirent * sd; - sd = sysfs_new_dirent(parent_sd, element); + sd = __sysfs_new_dirent(element); if (!sd) - return -ENOMEM; + goto out; sd->s_mode = mode; sd->s_type = type; @@ -95,7 +110,19 @@ int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, dentry->d_op = &sysfs_dentry_ops; } - return 0; +out: + return sd; +} + +int sysfs_make_dirent(struct sysfs_dirent * parent_sd, struct dentry * dentry, + void * element, umode_t mode, int type) +{ + struct sysfs_dirent *sd; + + sd = __sysfs_make_dirent(dentry, element, mode, type); + __sysfs_list_dirent(parent_sd, sd); + + return sd ? 0 : -ENOMEM; } static int init_dir(struct inode * inode) @@ -166,11 +193,11 @@ int sysfs_create_subdir(struct kobject * k, const char * n, struct dentry ** d) /** * sysfs_create_dir - create a directory for an object. - * @parent: parent parent object. * @kobj: object we're creating directory for. + * @shadow_parent: parent parent object. */ -int sysfs_create_dir(struct kobject * kobj) +int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent) { struct dentry * dentry = NULL; struct dentry * parent; @@ -178,7 +205,9 @@ int sysfs_create_dir(struct kobject * kobj) BUG_ON(!kobj); - if (kobj->parent) + if (shadow_parent) + parent = shadow_parent; + else if (kobj->parent) parent = kobj->parent->dentry; else if (sysfs_mount && sysfs_mount->mnt_sb) parent = sysfs_mount->mnt_sb->s_root; @@ -299,21 +328,12 @@ void sysfs_remove_subdir(struct dentry * d) } -/** - * 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) +static void __sysfs_remove_dir(struct dentry *dentry) { - struct dentry * dentry = dget(kobj->dentry); struct sysfs_dirent * parent_sd; struct sysfs_dirent * sd, * tmp; + dget(dentry); if (!dentry) return; @@ -334,32 +354,60 @@ void sysfs_remove_dir(struct kobject * kobj) * Drop reference from dget() on entrance. */ dput(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) +{ + __sysfs_remove_dir(kobj->dentry); kobj->dentry = NULL; } -int sysfs_rename_dir(struct kobject * kobj, const char *new_name) +int sysfs_rename_dir(struct kobject * kobj, struct dentry *new_parent, + const char *new_name) { int error = 0; - struct dentry * new_dentry, * parent; + struct dentry * new_dentry; - if (!strcmp(kobject_name(kobj), new_name)) - return -EINVAL; - - if (!kobj->parent) - return -EINVAL; + if (!new_parent) + return -EFAULT; down_write(&sysfs_rename_sem); - parent = kobj->parent->dentry; + mutex_lock(&new_parent->d_inode->i_mutex); - mutex_lock(&parent->d_inode->i_mutex); - - new_dentry = lookup_one_len(new_name, parent, strlen(new_name)); + new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name)); if (!IS_ERR(new_dentry)) { - if (!new_dentry->d_inode) { + /* By allowing two different directories with the + * same d_parent we allow this routine to move + * between different shadows of the same directory + */ + if (kobj->dentry->d_parent->d_inode != new_parent->d_inode) + return -EINVAL; + else if (new_dentry->d_parent->d_inode != new_parent->d_inode) + error = -EINVAL; + else if (new_dentry == kobj->dentry) + error = -EINVAL; + else if (!new_dentry->d_inode) { error = kobject_set_name(kobj, "%s", new_name); if (!error) { + struct sysfs_dirent *sd, *parent_sd; + d_add(new_dentry, NULL); d_move(kobj->dentry, new_dentry); + + sd = kobj->dentry->d_fsdata; + parent_sd = new_parent->d_fsdata; + + list_del_init(&sd->s_sibling); + list_add(&sd->s_sibling, &parent_sd->s_children); } else d_drop(new_dentry); @@ -367,7 +415,7 @@ int sysfs_rename_dir(struct kobject * kobj, const char *new_name) error = -EEXIST; dput(new_dentry); } - mutex_unlock(&parent->d_inode->i_mutex); + mutex_unlock(&new_parent->d_inode->i_mutex); up_write(&sysfs_rename_sem); return error; @@ -546,6 +594,95 @@ 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 sysfs_dirent *sd; + struct dentry *parent, *dir, *shadow; + struct inode *inode; + + dir = kobj->dentry; + inode = dir->d_inode; + parent = dir->d_parent; + 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_make_dirent(shadow, kobj, inode->i_mode, SYSFS_DIR); + if (!sd) + goto nomem; + + d_instantiate(shadow, igrab(inode)); + inc_nlink(inode); + inc_nlink(parent->d_inode); + shadow->d_op = &sysfs_dentry_ops; + + 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 46a277b0838..b20951c9376 100644 --- a/fs/sysfs/group.c +++ b/fs/sysfs/group.c @@ -13,6 +13,7 @@ #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 dbd820f9aee..542d2bcc73d 100644 --- a/fs/sysfs/inode.c +++ b/fs/sysfs/inode.c @@ -33,6 +33,16 @@ static 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 a1a58b97f32..f6a87a82488 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -23,7 +23,7 @@ static void sysfs_clear_inode(struct inode *inode); static struct super_operations sysfs_ops = { .statfs = simple_statfs, - .drop_inode = generic_delete_inode, + .drop_inode = sysfs_delete_inode, .clear_inode = sysfs_clear_inode, }; diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index 39c623fdc27..fe1cbfd208e 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -2,6 +2,7 @@ extern struct vfsmount * sysfs_mount; extern struct kmem_cache *sysfs_dir_cachep; +extern void sysfs_delete_inode(struct inode *inode); extern struct inode * sysfs_new_inode(mode_t mode, struct sysfs_dirent *); extern int sysfs_create(struct dentry *, int mode, int (*init)(struct inode *)); @@ -112,3 +113,7 @@ static inline void sysfs_put(struct sysfs_dirent * sd) 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; +} |