From 93b2b8e4aa4317e3fe6414d117deb5f3c362e8bb Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:15 -0500 Subject: sysfs, kernfs: introduce kernfs_create_dir[_ns]() Introduce kernfs interface to manipulate a directory which takes and returns sysfs_dirents. create_dir() is renamed to kernfs_create_dir_ns() and its argumantes and return value are updated. create_dir() usages are replaced with kernfs_create_dir_ns() and sysfs_create_subdir() usages are replaced with kernfs_create_dir(). Dup warnings are handled explicitly by sysfs users of the kernfs interface. sysfs_enable_ns() is renamed to kernfs_enable_ns(). This patch doesn't introduce any behavior changes. v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS. v3: kernfs_enable_ns() added. v4: Refreshed on top of "sysfs: drop kobj_ns_type handling, take #2" so that this patch removes sysfs_enable_ns(). Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 54 ++++++++++++++++++++++++++++++------------------------ fs/sysfs/group.c | 9 ++++++--- fs/sysfs/sysfs.h | 3 --- 3 files changed, 36 insertions(+), 30 deletions(-) (limited to 'fs/sysfs') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index aeb08bd3f3dd..cfbf4091fe5c 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -666,9 +666,18 @@ struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd, } EXPORT_SYMBOL_GPL(sysfs_get_dirent_ns); -static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, - const char *name, const void *ns, - struct sysfs_dirent **p_sd) +/** + * kernfs_create_dir_ns - create a directory + * @parent: parent in which to create a new directory + * @name: name of the new directory + * @priv: opaque data associated with the new directory + * @ns: optional namespace tag of the directory + * + * Returns the created node on success, ERR_PTR() value on failure. + */ +struct sysfs_dirent *kernfs_create_dir_ns(struct sysfs_dirent *parent, + const char *name, void *priv, + const void *ns) { umode_t mode = S_IFDIR | S_IRWXU | S_IRUGO | S_IXUGO; struct sysfs_addrm_cxt acxt; @@ -678,28 +687,21 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, /* allocate */ sd = sysfs_new_dirent(name, mode, SYSFS_DIR); if (!sd) - return -ENOMEM; + return ERR_PTR(-ENOMEM); sd->s_ns = ns; - sd->priv = kobj; + sd->priv = priv; /* link in */ sysfs_addrm_start(&acxt); - rc = sysfs_add_one(&acxt, sd, parent_sd); + rc = __sysfs_add_one(&acxt, sd, parent); sysfs_addrm_finish(&acxt); - if (rc == 0) - *p_sd = sd; - else - sysfs_put(sd); + if (!rc) + return sd; - return rc; -} - -int sysfs_create_subdir(struct kobject *kobj, const char *name, - struct sysfs_dirent **p_sd) -{ - return create_dir(kobj, kobj->sd, name, NULL, p_sd); + sysfs_put(sd); + return ERR_PTR(rc); } /** @@ -710,7 +712,6 @@ int sysfs_create_subdir(struct kobject *kobj, const char *name, int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) { struct sysfs_dirent *parent_sd, *sd; - int error = 0; BUG_ON(!kobj); @@ -722,10 +723,15 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) if (!parent_sd) return -ENOENT; - error = create_dir(kobj, parent_sd, kobject_name(kobj), ns, &sd); - if (!error) - kobj->sd = sd; - return error; + sd = kernfs_create_dir_ns(parent_sd, kobject_name(kobj), kobj, ns); + if (IS_ERR(sd)) { + if (PTR_ERR(sd) == -EEXIST) + sysfs_warn_dup(parent_sd, kobject_name(kobj)); + return PTR_ERR(sd); + } + + kobj->sd = sd; + return 0; } static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry, @@ -1005,14 +1011,14 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, } /** - * sysfs_enable_ns - enable namespace under a directory + * kernfs_enable_ns - enable namespace under a directory * @sd: directory of interest, should be empty * * This is to be called right after @sd is created to enable namespace * under it. All children of @sd must have non-NULL namespace tags and * only the ones which match the super_block's tag will be visible. */ -void sysfs_enable_ns(struct sysfs_dirent *sd) +void kernfs_enable_ns(struct sysfs_dirent *sd) { WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR); WARN_ON_ONCE(!RB_EMPTY_ROOT(&sd->s_dir.children)); diff --git a/fs/sysfs/group.c b/fs/sysfs/group.c index 4bd997340830..065689ddb4cb 100644 --- a/fs/sysfs/group.c +++ b/fs/sysfs/group.c @@ -101,9 +101,12 @@ static int internal_create_group(struct kobject *kobj, int update, return -EINVAL; } if (grp->name) { - error = sysfs_create_subdir(kobj, grp->name, &sd); - if (error) - return error; + sd = kernfs_create_dir(kobj->sd, grp->name, kobj); + if (IS_ERR(sd)) { + if (PTR_ERR(sd) == -EEXIST) + sysfs_warn_dup(kobj->sd, grp->name); + return PTR_ERR(sd); + } } else sd = kobj->sd; sysfs_get(sd); diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index a6f3fa3f02fe..9ac234ef4943 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -179,9 +179,6 @@ struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type); void release_sysfs_dirent(struct sysfs_dirent *sd); -int sysfs_create_subdir(struct kobject *kobj, const char *name, - struct sysfs_dirent **p_sd); - static inline struct sysfs_dirent *__sysfs_get(struct sysfs_dirent *sd) { if (sd) { -- cgit v1.2.3-70-g09d2