From c84a3b27798dfce928b867fa1c9f3c3fd66f0a31 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sat, 23 Nov 2013 18:01:46 -0500 Subject: sysfs: drop kobj_ns_type handling, take #2 The way namespace tags are implemented in sysfs is more complicated than necessary. As each tag is a pointer value and required to be non-NULL under a namespace enabled parent, there's no need to record separately what type each tag is. If multiple namespace types are needed, which currently aren't, we can simply compare the tag to a set of allowed tags in the superblock assuming that the tags, being pointers, won't have the same value across multiple types. This patch rips out kobj_ns_type handling from sysfs. sysfs now has an enable switch to turn on namespace under a node. If enabled, all children are required to have non-NULL namespace tags and filtered against the super_block's tag. kobject namespace determination is now performed in lib/kobject.c::create_dir() making sysfs_read_ns_type() unnecessary. The sanity checks are also moved. create_dir() is restructured to ease such addition. This removes most kobject namespace knowledge from sysfs proper which will enable proper separation and layering of sysfs. This is the second try. The first one was cb26a311578e ("sysfs: drop kobj_ns_type handling") which tried to automatically enable namespace if there are children with non-NULL namespace tags; however, it was broken for symlinks as they should inherit the target's tag iff namespace is enabled in the parent. This led to namespace filtering enabled incorrectly for wireless net class devices through phy80211 symlinks and thus network configuration failure. a1212d278c05 ("Revert "sysfs: drop kobj_ns_type handling"") reverted the commit. This shouldn't introduce any behavior changes, for real. v2: Dummy implementation of sysfs_enable_ns() for !CONFIG_SYSFS was missing and caused build failure. Reported by kbuild test robot. Signed-off-by: Tejun Heo Reported-by: Linus Torvalds Cc: Eric W. Biederman Cc: Kay Sievers Cc: Greg Kroah-Hartman Cc: kbuild test robot Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 92 +++++++++++++++++++++++----------------------------------- 1 file changed, 36 insertions(+), 56 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 5e73d6626e50..b3cf61dc57c1 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -279,7 +279,6 @@ static int sysfs_dentry_delete(const struct dentry *dentry) static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) { struct sysfs_dirent *sd; - int type; if (flags & LOOKUP_RCU) return -ECHILD; @@ -300,13 +299,9 @@ static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) goto out_bad; /* The sysfs dirent has been moved to a different namespace */ - type = KOBJ_NS_TYPE_NONE; - if (sd->s_parent) { - type = sysfs_ns_type(sd->s_parent); - if (type != KOBJ_NS_TYPE_NONE && - sysfs_info(dentry->d_sb)->ns[type] != sd->s_ns) - goto out_bad; - } + if (sd->s_parent && (sd->s_parent->s_flags & SYSFS_FLAG_NS) && + sysfs_info(dentry->d_sb)->ns != sd->s_ns) + goto out_bad; mutex_unlock(&sysfs_mutex); out_valid: @@ -423,13 +418,14 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt) int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, struct sysfs_dirent *parent_sd) { + bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; struct sysfs_inode_attrs *ps_iattr; int ret; - if (!!sysfs_ns_type(parent_sd) != !!sd->s_ns) { + if (has_ns != (bool)sd->s_ns) { WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", - sysfs_ns_type(parent_sd) ? "required" : "invalid", - parent_sd->s_name, sd->s_name); + has_ns ? "required" : "invalid", + parent_sd->s_name, sd->s_name); return -EINVAL; } @@ -610,12 +606,13 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, const void *ns) { struct rb_node *node = parent_sd->s_dir.children.rb_node; + bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; unsigned int hash; - if (!!sysfs_ns_type(parent_sd) != !!ns) { + if (has_ns != (bool)ns) { WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", - sysfs_ns_type(parent_sd) ? "required" : "invalid", - parent_sd->s_name, name); + has_ns ? "required" : "invalid", + parent_sd->s_name, name); return NULL; } @@ -667,7 +664,6 @@ 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, - enum kobj_ns_type type, const char *name, const void *ns, struct sysfs_dirent **p_sd) { @@ -681,7 +677,6 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, if (!sd) return -ENOMEM; - sd->s_flags |= (type << SYSFS_NS_TYPE_SHIFT); sd->s_ns = ns; sd->s_dir.kobj = kobj; @@ -701,33 +696,7 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, int sysfs_create_subdir(struct kobject *kobj, const char *name, struct sysfs_dirent **p_sd) { - return create_dir(kobj, kobj->sd, - KOBJ_NS_TYPE_NONE, name, NULL, p_sd); -} - -/** - * sysfs_read_ns_type: return associated ns_type - * @kobj: the kobject being queried - * - * Each kobject can be tagged with exactly one namespace type - * (i.e. network or user). Return the ns_type associated with - * this object if any - */ -static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj) -{ - const struct kobj_ns_type_operations *ops; - enum kobj_ns_type type; - - ops = kobj_child_ns_ops(kobj); - if (!ops) - return KOBJ_NS_TYPE_NONE; - - type = ops->type; - BUG_ON(type <= KOBJ_NS_TYPE_NONE); - BUG_ON(type >= KOBJ_NS_TYPES); - BUG_ON(!kobj_ns_type_registered(type)); - - return type; + return create_dir(kobj, kobj->sd, name, NULL, p_sd); } /** @@ -737,7 +706,6 @@ static enum kobj_ns_type sysfs_read_ns_type(struct kobject *kobj) */ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) { - enum kobj_ns_type type; struct sysfs_dirent *parent_sd, *sd; int error = 0; @@ -751,9 +719,7 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) if (!parent_sd) return -ENOENT; - type = sysfs_read_ns_type(kobj); - - error = create_dir(kobj, parent_sd, type, kobject_name(kobj), ns, &sd); + error = create_dir(kobj, parent_sd, kobject_name(kobj), ns, &sd); if (!error) kobj->sd = sd; return error; @@ -767,13 +733,12 @@ static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry, struct sysfs_dirent *parent_sd = parent->d_fsdata; struct sysfs_dirent *sd; struct inode *inode; - enum kobj_ns_type type; - const void *ns; + const void *ns = NULL; mutex_lock(&sysfs_mutex); - type = sysfs_ns_type(parent_sd); - ns = sysfs_info(dir->i_sb)->ns[type]; + if (parent_sd->s_flags & SYSFS_FLAG_NS) + ns = sysfs_info(dir->i_sb)->ns; sd = sysfs_find_dirent(parent_sd, dentry->d_name.name, ns); @@ -1029,6 +994,21 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, return sysfs_rename(sd, new_parent_sd, sd->s_name, new_ns); } +/** + * sysfs_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) +{ + WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR); + WARN_ON_ONCE(!RB_EMPTY_ROOT(&sd->s_dir.children)); + sd->s_flags |= SYSFS_FLAG_NS; +} + /* Relationship between s_mode and the DT_xxx types */ static inline unsigned char dt_type(struct sysfs_dirent *sd) { @@ -1096,15 +1076,15 @@ static int sysfs_readdir(struct file *file, struct dir_context *ctx) struct dentry *dentry = file->f_path.dentry; struct sysfs_dirent *parent_sd = dentry->d_fsdata; struct sysfs_dirent *pos = file->private_data; - enum kobj_ns_type type; - const void *ns; - - type = sysfs_ns_type(parent_sd); - ns = sysfs_info(dentry->d_sb)->ns[type]; + const void *ns = NULL; if (!dir_emit_dots(file, ctx)) return 0; mutex_lock(&sysfs_mutex); + + if (parent_sd->s_flags & SYSFS_FLAG_NS) + ns = sysfs_info(dentry->d_sb)->ns; + for (pos = sysfs_dir_pos(ns, parent_sd, ctx->pos, pos); pos; pos = sysfs_dir_next_pos(ns, parent_sd, ctx->pos, pos)) { -- cgit v1.2.3 From ae2108ad32f5ca55e9895d5597e6552be1607569 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sat, 23 Nov 2013 17:21:47 -0500 Subject: sysfs: make __sysfs_add_one() fail if the parent isn't a directory Currently the kobject based interface guarantees that a parent sysfs_dirent is always a directory; however, the planned kernfs interface will be directly based on sysfs_dirents and the caller may specify non-directory node as the parent. Add an explicit check in __sysfs_add_one() so that such attempts fail with -EINVAL. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index b3cf61dc57c1..98701c00b9b0 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -429,6 +429,9 @@ int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, return -EINVAL; } + if (sysfs_type(parent_sd) != SYSFS_DIR) + return -EINVAL; + sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); sd->s_parent = sysfs_get(parent_sd); -- cgit v1.2.3 From 879f40d193bb3c6c13930e88e3e9d5d7baf84d19 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sat, 23 Nov 2013 17:21:49 -0500 Subject: sysfs, kernfs: introduce kernfs_remove[_by_name[_ns]]() Introduce kernfs removal interfaces - kernfs_remove() and kernfs_remove_by_name[_ns](). These are just renames of sysfs_remove() and sysfs_hash_and_remove(). No functional changes. v2: Dummy kernfs_remove_by_name_ns() for !CONFIG_SYSFS updated to return -ENOSYS instead of 0. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 98701c00b9b0..edbde4e6e5e0 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -829,8 +829,8 @@ static struct sysfs_dirent *sysfs_next_descendant_post(struct sysfs_dirent *pos, return pos->s_parent; } -static void __sysfs_remove(struct sysfs_addrm_cxt *acxt, - struct sysfs_dirent *sd) +static void __kernfs_remove(struct sysfs_addrm_cxt *acxt, + struct sysfs_dirent *sd) { struct sysfs_dirent *pos, *next; @@ -849,22 +849,22 @@ static void __sysfs_remove(struct sysfs_addrm_cxt *acxt, } /** - * sysfs_remove - remove a sysfs_dirent recursively + * kernfs_remove - remove a sysfs_dirent recursively * @sd: the sysfs_dirent to remove * * Remove @sd along with all its subdirectories and files. */ -void sysfs_remove(struct sysfs_dirent *sd) +void kernfs_remove(struct sysfs_dirent *sd) { struct sysfs_addrm_cxt acxt; sysfs_addrm_start(&acxt); - __sysfs_remove(&acxt, sd); + __kernfs_remove(&acxt, sd); sysfs_addrm_finish(&acxt); } /** - * sysfs_hash_and_remove - find a sysfs_dirent by name and remove it + * kernfs_remove_by_name_ns - find a sysfs_dirent by name and remove it * @dir_sd: parent of the target * @name: name of the sysfs_dirent to remove * @ns: namespace tag of the sysfs_dirent to remove @@ -872,8 +872,8 @@ void sysfs_remove(struct sysfs_dirent *sd) * Look for the sysfs_dirent with @name and @ns under @dir_sd and remove * it. Returns 0 on success, -ENOENT if such entry doesn't exist. */ -int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name, - const void *ns) +int kernfs_remove_by_name_ns(struct sysfs_dirent *dir_sd, const char *name, + const void *ns) { struct sysfs_addrm_cxt acxt; struct sysfs_dirent *sd; @@ -888,7 +888,7 @@ int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name, sd = sysfs_find_dirent(dir_sd, name, ns); if (sd) - __sysfs_remove(&acxt, sd); + __kernfs_remove(&acxt, sd); sysfs_addrm_finish(&acxt); @@ -928,7 +928,7 @@ void sysfs_remove_dir(struct kobject *kobj) if (sd) { WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR); - sysfs_remove(sd); + kernfs_remove(sd); } } -- cgit v1.2.3 From 890ece160c6465b49c42975d529c3481d89da8f5 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sat, 23 Nov 2013 17:21:51 -0500 Subject: sysfs, kernfs: introduce kernfs_rename[_ns]() Introduce kernfs rename interface, krenfs_rename[_ns](). This is just rename of sysfs_rename(). No functional changes. Function comment is added to kernfs_rename_ns() and @new_parent_sd is renamed to @new_parent for consistency with other kernfs interfaces. v2: Dummy implementation for !CONFIG_SYSFS updated to return -ENOSYS. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 23 +++++++++++++++-------- 1 file changed, 15 insertions(+), 8 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index edbde4e6e5e0..5ba896630d04 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -932,20 +932,27 @@ void sysfs_remove_dir(struct kobject *kobj) } } -int sysfs_rename(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent_sd, - const char *new_name, const void *new_ns) +/** + * kernfs_rename_ns - move and rename a kernfs_node + * @sd: target node + * @new_parent: new parent to put @sd under + * @new_name: new name + * @new_ns: new namespace tag + */ +int kernfs_rename_ns(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent, + const char *new_name, const void *new_ns) { int error; mutex_lock(&sysfs_mutex); error = 0; - if ((sd->s_parent == new_parent_sd) && (sd->s_ns == new_ns) && + if ((sd->s_parent == new_parent) && (sd->s_ns == new_ns) && (strcmp(sd->s_name, new_name) == 0)) goto out; /* nothing to rename */ error = -EEXIST; - if (sysfs_find_dirent(new_parent_sd, new_name, new_ns)) + if (sysfs_find_dirent(new_parent, new_name, new_ns)) goto out; /* rename sysfs_dirent */ @@ -963,11 +970,11 @@ int sysfs_rename(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent_sd, * Move to the appropriate place in the appropriate directories rbtree. */ sysfs_unlink_sibling(sd); - sysfs_get(new_parent_sd); + sysfs_get(new_parent); sysfs_put(sd->s_parent); sd->s_ns = new_ns; sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); - sd->s_parent = new_parent_sd; + sd->s_parent = new_parent; sysfs_link_sibling(sd); error = 0; @@ -981,7 +988,7 @@ int sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name, { struct sysfs_dirent *parent_sd = kobj->sd->s_parent; - return sysfs_rename(kobj->sd, parent_sd, new_name, new_ns); + return kernfs_rename_ns(kobj->sd, parent_sd, new_name, new_ns); } int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, @@ -994,7 +1001,7 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, new_parent_sd = new_parent_kobj && new_parent_kobj->sd ? new_parent_kobj->sd : &sysfs_root; - return sysfs_rename(sd, new_parent_sd, sd->s_name, new_ns); + return kernfs_rename_ns(sd, new_parent_sd, sd->s_name, new_ns); } /** -- cgit v1.2.3 From 7c6e2d362c19f01e6d6c8be59d83a89722032884 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:14 -0500 Subject: sysfs, kernfs: replace sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with ->priv A directory sysfs_dirent points to the associated kobj. A regular or bin file points to the associated [bin_]attribute. This patch replaces sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with void * ->priv. This is to prepare for kernfs interface so that sysfs can specify the private data in the same way for directories and files. This lower debuggability but not by much - the whole thing was overlaid in a union anyway. If debuggability becomes an issue, we can later add ->priv accessors which explicitly check for the sysfs_dirent type and performs casting. This patch doesn't introduce any behavior difference. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 5ba896630d04..aeb08bd3f3dd 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -681,7 +681,7 @@ static int create_dir(struct kobject *kobj, struct sysfs_dirent *parent_sd, return -ENOMEM; sd->s_ns = ns; - sd->s_dir.kobj = kobj; + sd->priv = kobj; /* link in */ sysfs_addrm_start(&acxt); -- cgit v1.2.3 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 ++++++++++++++++++++++++++++++------------------------ 1 file changed, 30 insertions(+), 24 deletions(-) (limited to 'fs/sysfs/dir.c') 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)); -- cgit v1.2.3 From 2d0cfbec2a95c16818960fda1dfa815fd1a62070 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:25 -0500 Subject: sysfs, kernfs: remove sysfs_add_one() sysfs_add_one() is a wrapper around __sysfs_add_one() which prints out duplicate name warning if __sysfs_add_one() fails with -EEXIST. The previous kernfs conversions moved all dup warnings to sysfs interface functions and sysfs_add_one() doesn't have any user left. Remove sysfs_add_one() and update __sysfs_add_one() to take its name. This patch doesn't make any functional changes. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 41 ++++------------------------------------- 1 file changed, 4 insertions(+), 37 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index cfbf4091fe5c..e88e9a94a083 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -395,7 +395,7 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt) } /** - * __sysfs_add_one - add sysfs_dirent to parent without warning + * sysfs_add_one - add sysfs_dirent to parent without warning * @acxt: addrm context to use * @sd: sysfs_dirent to be added * @parent_sd: the parent sysfs_dirent to add @sd to @@ -415,8 +415,8 @@ void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt) * 0 on success, -EEXIST if entry with the given name already * exists. */ -int __sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, - struct sysfs_dirent *parent_sd) +int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, + struct sysfs_dirent *parent_sd) { bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; struct sysfs_inode_attrs *ps_iattr; @@ -487,39 +487,6 @@ void sysfs_warn_dup(struct sysfs_dirent *parent, const char *name) kfree(path); } -/** - * sysfs_add_one - add sysfs_dirent to parent - * @acxt: addrm context to use - * @sd: sysfs_dirent to be added - * @parent_sd: the parent sysfs_dirent to add @sd to - * - * Get @parent_sd and set @sd->s_parent to it and increment nlink of - * the parent inode if @sd is a directory and link into the children - * list of the parent. - * - * This function should be called between calls to - * sysfs_addrm_start() and sysfs_addrm_finish() and should be - * passed the same @acxt as passed to sysfs_addrm_start(). - * - * LOCKING: - * Determined by sysfs_addrm_start(). - * - * RETURNS: - * 0 on success, -EEXIST if entry with the given name already - * exists. - */ -int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, - struct sysfs_dirent *parent_sd) -{ - int ret; - - ret = __sysfs_add_one(acxt, sd, parent_sd); - - if (ret == -EEXIST) - sysfs_warn_dup(parent_sd, sd->s_name); - return ret; -} - /** * sysfs_remove_one - remove sysfs_dirent from parent * @acxt: addrm context to use @@ -694,7 +661,7 @@ struct sysfs_dirent *kernfs_create_dir_ns(struct sysfs_dirent *parent, /* link in */ sysfs_addrm_start(&acxt); - rc = __sysfs_add_one(&acxt, sd, parent); + rc = sysfs_add_one(&acxt, sd, parent); sysfs_addrm_finish(&acxt); if (!rc) -- cgit v1.2.3 From 517e64f57883bd63c5a4ab8b3d0d3ed68c55d0cf Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:29 -0500 Subject: sysfs, kernfs: revamp sysfs_dirent active_ref lockdep annotation Currently, sysfs_dirent active_ref lockdep annotation uses attribute->[s]key as the lockdep key, which forces kernfs_create_file_ns() to assume that sysfs_dirent->priv is pointing to a struct attribute which may not be true for non-sysfs users. This patch restructures the lockdep annotation such that * kernfs_ops contains lockdep_key which is used by default for files created kernfs_create_file_ns(). * kernfs_create_file_ns_key() is introduced which takes an extra @key argument. The created file will use the specified key for active_ref lockdep annotation. If NULL is specified, lockdep for the file is disabled. * sysfs_add_file_mode_ns() is updated to use kernfs_create_file_ns_key() with the appropriate key from the attribute or NULL if ignore_lockdep is set. This makes the lockdep annotation properly contained in kernfs while allowing sysfs to cleanly keep its current behavior. This patch doesn't introduce any behavior differences. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index e88e9a94a083..8f2d577b5f64 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -150,7 +150,7 @@ struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) if (!atomic_inc_unless_negative(&sd->s_active)) return NULL; - if (likely(!sysfs_ignore_lockdep(sd))) + if (sd->s_flags & SYSFS_FLAG_LOCKDEP) rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_); return sd; } @@ -169,7 +169,7 @@ void sysfs_put_active(struct sysfs_dirent *sd) if (unlikely(!sd)) return; - if (likely(!sysfs_ignore_lockdep(sd))) + if (sd->s_flags & SYSFS_FLAG_LOCKDEP) rwsem_release(&sd->dep_map, 1, _RET_IP_); v = atomic_dec_return(&sd->s_active); if (likely(v != SD_DEACTIVATED_BIAS)) -- cgit v1.2.3 From ccf73cf336dc55bc52748205dee998d2fd4a8808 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:30 -0500 Subject: sysfs, kernfs: introduce kernfs[_find_and]_get() and kernfs_put() Introduce kernfs interface for finding, getting and putting sysfs_dirents. * sysfs_find_dirent() is renamed to kernfs_find_ns() and lockdep assertion for sysfs_mutex is added. * sysfs_get_dirent_ns() is renamed to kernfs_find_and_get(). * Macro inline dancing around __sysfs_get/put() are removed and kernfs_get/put() are made proper functions implemented in fs/sysfs/dir.c. While the conversions are mostly equivalent, there's one difference - kernfs_get() doesn't return the input param as its return value. This change is intentional. While passing through the input increases writability in some areas, it is unnecessary and has been shown to cause confusion regarding how the last ref is handled. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 117 +++++++++++++++++++++++++++++++++------------------------ 1 file changed, 67 insertions(+), 50 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 8f2d577b5f64..0d806efcc9a6 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -240,10 +240,31 @@ static void sysfs_free_ino(unsigned int ino) spin_unlock(&sysfs_ino_lock); } -void release_sysfs_dirent(struct sysfs_dirent *sd) +/** + * kernfs_get - get a reference count on a sysfs_dirent + * @sd: the target sysfs_dirent + */ +void kernfs_get(struct sysfs_dirent *sd) +{ + if (sd) { + WARN_ON(!atomic_read(&sd->s_count)); + atomic_inc(&sd->s_count); + } +} +EXPORT_SYMBOL_GPL(kernfs_get); + +/** + * kernfs_put - put a reference count on a sysfs_dirent + * @sd: the target sysfs_dirent + * + * Put a reference count of @sd and destroy it if it reached zero. + */ +void kernfs_put(struct sysfs_dirent *sd) { struct sysfs_dirent *parent_sd; + if (!sd || !atomic_dec_and_test(&sd->s_count)) + return; repeat: /* Moving/renaming is always done while holding reference. * sd->s_parent won't change beneath us. @@ -255,7 +276,7 @@ void release_sysfs_dirent(struct sysfs_dirent *sd) parent_sd ? parent_sd->s_name : "", sd->s_name); if (sysfs_type(sd) == SYSFS_KOBJ_LINK) - sysfs_put(sd->s_symlink.target_sd); + kernfs_put(sd->s_symlink.target_sd); if (sysfs_type(sd) & SYSFS_COPY_NAME) kfree(sd->s_name); if (sd->s_iattr && sd->s_iattr->ia_secdata) @@ -269,6 +290,7 @@ void release_sysfs_dirent(struct sysfs_dirent *sd) if (sd && atomic_dec_and_test(&sd->s_count)) goto repeat; } +EXPORT_SYMBOL_GPL(kernfs_put); static int sysfs_dentry_delete(const struct dentry *dentry) { @@ -331,7 +353,7 @@ out_bad: static void sysfs_dentry_release(struct dentry *dentry) { - sysfs_put(dentry->d_fsdata); + kernfs_put(dentry->d_fsdata); } const struct dentry_operations sysfs_dentry_ops = { @@ -433,7 +455,8 @@ int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, return -EINVAL; sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); - sd->s_parent = sysfs_get(parent_sd); + sd->s_parent = parent_sd; + kernfs_get(parent_sd); ret = sysfs_link_sibling(sd); if (ret) @@ -553,36 +576,33 @@ void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) sysfs_deactivate(sd); sysfs_unmap_bin_file(sd); - sysfs_put(sd); + kernfs_put(sd); } } /** - * sysfs_find_dirent - find sysfs_dirent with the given name - * @parent_sd: sysfs_dirent to search under - * @name: name to look for - * @ns: the namespace tag to use - * - * Look for sysfs_dirent with name @name under @parent_sd. - * - * LOCKING: - * mutex_lock(sysfs_mutex) + * kernfs_find_ns - find sysfs_dirent with the given name + * @parent: sysfs_dirent to search under + * @name: name to look for + * @ns: the namespace tag to use * - * RETURNS: - * Pointer to sysfs_dirent if found, NULL if not. + * Look for sysfs_dirent with name @name under @parent. Returns pointer to + * the found sysfs_dirent on success, %NULL on failure. */ -struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, - const unsigned char *name, - const void *ns) +static struct sysfs_dirent *kernfs_find_ns(struct sysfs_dirent *parent, + const unsigned char *name, + const void *ns) { - struct rb_node *node = parent_sd->s_dir.children.rb_node; - bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; + struct rb_node *node = parent->s_dir.children.rb_node; + bool has_ns = parent->s_flags & SYSFS_FLAG_NS; unsigned int hash; + lockdep_assert_held(&sysfs_mutex); + if (has_ns != (bool)ns) { WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", has_ns ? "required" : "invalid", - parent_sd->s_name, name); + parent->s_name, name); return NULL; } @@ -604,34 +624,28 @@ struct sysfs_dirent *sysfs_find_dirent(struct sysfs_dirent *parent_sd, } /** - * sysfs_get_dirent_ns - find and get sysfs_dirent with the given name - * @parent_sd: sysfs_dirent to search under - * @name: name to look for - * @ns: the namespace tag to use - * - * Look for sysfs_dirent with name @name under @parent_sd and get - * it if found. - * - * LOCKING: - * Kernel thread context (may sleep). Grabs sysfs_mutex. + * kernfs_find_and_get_ns - find and get sysfs_dirent with the given name + * @parent: sysfs_dirent to search under + * @name: name to look for + * @ns: the namespace tag to use * - * RETURNS: - * Pointer to sysfs_dirent if found, NULL if not. + * Look for sysfs_dirent with name @name under @parent and get a reference + * if found. This function may sleep and returns pointer to the found + * sysfs_dirent on success, %NULL on failure. */ -struct sysfs_dirent *sysfs_get_dirent_ns(struct sysfs_dirent *parent_sd, - const unsigned char *name, - const void *ns) +struct sysfs_dirent *kernfs_find_and_get_ns(struct sysfs_dirent *parent, + const char *name, const void *ns) { struct sysfs_dirent *sd; mutex_lock(&sysfs_mutex); - sd = sysfs_find_dirent(parent_sd, name, ns); - sysfs_get(sd); + sd = kernfs_find_ns(parent, name, ns); + kernfs_get(sd); mutex_unlock(&sysfs_mutex); return sd; } -EXPORT_SYMBOL_GPL(sysfs_get_dirent_ns); +EXPORT_SYMBOL_GPL(kernfs_find_and_get_ns); /** * kernfs_create_dir_ns - create a directory @@ -667,7 +681,7 @@ struct sysfs_dirent *kernfs_create_dir_ns(struct sysfs_dirent *parent, if (!rc) return sd; - sysfs_put(sd); + kernfs_put(sd); return ERR_PTR(rc); } @@ -716,14 +730,15 @@ static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry, if (parent_sd->s_flags & SYSFS_FLAG_NS) ns = sysfs_info(dir->i_sb)->ns; - sd = sysfs_find_dirent(parent_sd, dentry->d_name.name, ns); + sd = kernfs_find_ns(parent_sd, dentry->d_name.name, ns); /* no such entry */ if (!sd) { ret = ERR_PTR(-ENOENT); goto out_unlock; } - dentry->d_fsdata = sysfs_get(sd); + kernfs_get(sd); + dentry->d_fsdata = sd; /* attach dentry and inode */ inode = sysfs_get_inode(dir->i_sb, sd); @@ -859,7 +874,7 @@ int kernfs_remove_by_name_ns(struct sysfs_dirent *dir_sd, const char *name, sysfs_addrm_start(&acxt); - sd = sysfs_find_dirent(dir_sd, name, ns); + sd = kernfs_find_ns(dir_sd, name, ns); if (sd) __kernfs_remove(&acxt, sd); @@ -925,7 +940,7 @@ int kernfs_rename_ns(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent, goto out; /* nothing to rename */ error = -EEXIST; - if (sysfs_find_dirent(new_parent, new_name, new_ns)) + if (kernfs_find_ns(new_parent, new_name, new_ns)) goto out; /* rename sysfs_dirent */ @@ -943,8 +958,8 @@ int kernfs_rename_ns(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent, * Move to the appropriate place in the appropriate directories rbtree. */ sysfs_unlink_sibling(sd); - sysfs_get(new_parent); - sysfs_put(sd->s_parent); + kernfs_get(new_parent); + kernfs_put(sd->s_parent); sd->s_ns = new_ns; sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); sd->s_parent = new_parent; @@ -1000,7 +1015,7 @@ static inline unsigned char dt_type(struct sysfs_dirent *sd) static int sysfs_dir_release(struct inode *inode, struct file *filp) { - sysfs_put(filp->private_data); + kernfs_put(filp->private_data); return 0; } @@ -1011,7 +1026,7 @@ static struct sysfs_dirent *sysfs_dir_pos(const void *ns, int valid = !(pos->s_flags & SYSFS_FLAG_REMOVED) && pos->s_parent == parent_sd && hash == pos->s_hash; - sysfs_put(pos); + kernfs_put(pos); if (!valid) pos = NULL; } @@ -1075,8 +1090,10 @@ static int sysfs_readdir(struct file *file, struct dir_context *ctx) unsigned int type = dt_type(pos); int len = strlen(name); ino_t ino = pos->s_ino; + ctx->pos = pos->s_hash; - file->private_data = sysfs_get(pos); + file->private_data = pos; + kernfs_get(pos); mutex_unlock(&sysfs_mutex); if (!dir_emit(ctx, name, len, ino, type)) -- cgit v1.2.3 From fd7b9f7b9776b11df629e9dd3865320bf57ce588 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:33 -0500 Subject: sysfs, kernfs: move dir core code to fs/kernfs/dir.c Move core dir code to fs/kernfs/dir.c. fs/sysfs/dir.c now only contains sysfs_warn_dup() and sysfs wrappers around kernfs interfaces. The respective declarations in fs/sysfs/sysfs.h are moved to fs/kernfs/kernfs-internal.h. This is pure relocation. v2: sysfs_symlink_target_lock was mistakenly relocated to kernfs. It should remain with sysfs. Fixed. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 986 --------------------------------------------------------- 1 file changed, 986 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 0d806efcc9a6..e5c4e7118050 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -13,468 +13,12 @@ #undef DEBUG #include -#include -#include #include -#include -#include -#include -#include #include -#include -#include #include "sysfs.h" -DEFINE_MUTEX(sysfs_mutex); DEFINE_SPINLOCK(sysfs_symlink_target_lock); -#define to_sysfs_dirent(X) rb_entry((X), struct sysfs_dirent, s_rb) - -static DEFINE_SPINLOCK(sysfs_ino_lock); -static DEFINE_IDA(sysfs_ino_ida); - -/** - * sysfs_name_hash - * @name: Null terminated string to hash - * @ns: Namespace tag to hash - * - * Returns 31 bit hash of ns + name (so it fits in an off_t ) - */ -static unsigned int sysfs_name_hash(const char *name, const void *ns) -{ - unsigned long hash = init_name_hash(); - unsigned int len = strlen(name); - while (len--) - hash = partial_name_hash(*name++, hash); - hash = (end_name_hash(hash) ^ hash_ptr((void *)ns, 31)); - hash &= 0x7fffffffU; - /* Reserve hash numbers 0, 1 and INT_MAX for magic directory entries */ - if (hash < 1) - hash += 2; - if (hash >= INT_MAX) - hash = INT_MAX - 1; - return hash; -} - -static int sysfs_name_compare(unsigned int hash, const char *name, - const void *ns, const struct sysfs_dirent *sd) -{ - if (hash != sd->s_hash) - return hash - sd->s_hash; - if (ns != sd->s_ns) - return ns - sd->s_ns; - return strcmp(name, sd->s_name); -} - -static int sysfs_sd_compare(const struct sysfs_dirent *left, - const struct sysfs_dirent *right) -{ - return sysfs_name_compare(left->s_hash, left->s_name, left->s_ns, - right); -} - -/** - * sysfs_link_sibling - link sysfs_dirent into sibling rbtree - * @sd: sysfs_dirent of interest - * - * Link @sd into its sibling rbtree which starts from - * sd->s_parent->s_dir.children. - * - * Locking: - * mutex_lock(sysfs_mutex) - * - * RETURNS: - * 0 on susccess -EEXIST on failure. - */ -static int sysfs_link_sibling(struct sysfs_dirent *sd) -{ - struct rb_node **node = &sd->s_parent->s_dir.children.rb_node; - struct rb_node *parent = NULL; - - if (sysfs_type(sd) == SYSFS_DIR) - sd->s_parent->s_dir.subdirs++; - - while (*node) { - struct sysfs_dirent *pos; - int result; - - pos = to_sysfs_dirent(*node); - parent = *node; - result = sysfs_sd_compare(sd, pos); - if (result < 0) - node = &pos->s_rb.rb_left; - else if (result > 0) - node = &pos->s_rb.rb_right; - else - return -EEXIST; - } - /* add new node and rebalance the tree */ - rb_link_node(&sd->s_rb, parent, node); - rb_insert_color(&sd->s_rb, &sd->s_parent->s_dir.children); - return 0; -} - -/** - * sysfs_unlink_sibling - unlink sysfs_dirent from sibling rbtree - * @sd: sysfs_dirent of interest - * - * Unlink @sd from its sibling rbtree which starts from - * sd->s_parent->s_dir.children. - * - * Locking: - * mutex_lock(sysfs_mutex) - */ -static void sysfs_unlink_sibling(struct sysfs_dirent *sd) -{ - if (sysfs_type(sd) == SYSFS_DIR) - sd->s_parent->s_dir.subdirs--; - - rb_erase(&sd->s_rb, &sd->s_parent->s_dir.children); -} - -/** - * sysfs_get_active - get an active reference to sysfs_dirent - * @sd: sysfs_dirent to get an active reference to - * - * Get an active reference of @sd. This function is noop if @sd - * is NULL. - * - * RETURNS: - * Pointer to @sd on success, NULL on failure. - */ -struct sysfs_dirent *sysfs_get_active(struct sysfs_dirent *sd) -{ - if (unlikely(!sd)) - return NULL; - - if (!atomic_inc_unless_negative(&sd->s_active)) - return NULL; - - if (sd->s_flags & SYSFS_FLAG_LOCKDEP) - rwsem_acquire_read(&sd->dep_map, 0, 1, _RET_IP_); - return sd; -} - -/** - * sysfs_put_active - put an active reference to sysfs_dirent - * @sd: sysfs_dirent to put an active reference to - * - * Put an active reference to @sd. This function is noop if @sd - * is NULL. - */ -void sysfs_put_active(struct sysfs_dirent *sd) -{ - int v; - - if (unlikely(!sd)) - return; - - if (sd->s_flags & SYSFS_FLAG_LOCKDEP) - rwsem_release(&sd->dep_map, 1, _RET_IP_); - v = atomic_dec_return(&sd->s_active); - if (likely(v != SD_DEACTIVATED_BIAS)) - return; - - /* atomic_dec_return() is a mb(), we'll always see the updated - * sd->u.completion. - */ - complete(sd->u.completion); -} - -/** - * sysfs_deactivate - deactivate sysfs_dirent - * @sd: sysfs_dirent to deactivate - * - * Deny new active references and drain existing ones. - */ -static void sysfs_deactivate(struct sysfs_dirent *sd) -{ - DECLARE_COMPLETION_ONSTACK(wait); - int v; - - BUG_ON(!(sd->s_flags & SYSFS_FLAG_REMOVED)); - - if (!(sysfs_type(sd) & SYSFS_ACTIVE_REF)) - return; - - sd->u.completion = (void *)&wait; - - rwsem_acquire(&sd->dep_map, 0, 0, _RET_IP_); - /* atomic_add_return() is a mb(), put_active() will always see - * the updated sd->u.completion. - */ - v = atomic_add_return(SD_DEACTIVATED_BIAS, &sd->s_active); - - if (v != SD_DEACTIVATED_BIAS) { - lock_contended(&sd->dep_map, _RET_IP_); - wait_for_completion(&wait); - } - - lock_acquired(&sd->dep_map, _RET_IP_); - rwsem_release(&sd->dep_map, 1, _RET_IP_); -} - -static int sysfs_alloc_ino(unsigned int *pino) -{ - int ino, rc; - - retry: - spin_lock(&sysfs_ino_lock); - rc = ida_get_new_above(&sysfs_ino_ida, 2, &ino); - spin_unlock(&sysfs_ino_lock); - - if (rc == -EAGAIN) { - if (ida_pre_get(&sysfs_ino_ida, GFP_KERNEL)) - goto retry; - rc = -ENOMEM; - } - - *pino = ino; - return rc; -} - -static void sysfs_free_ino(unsigned int ino) -{ - spin_lock(&sysfs_ino_lock); - ida_remove(&sysfs_ino_ida, ino); - spin_unlock(&sysfs_ino_lock); -} - -/** - * kernfs_get - get a reference count on a sysfs_dirent - * @sd: the target sysfs_dirent - */ -void kernfs_get(struct sysfs_dirent *sd) -{ - if (sd) { - WARN_ON(!atomic_read(&sd->s_count)); - atomic_inc(&sd->s_count); - } -} -EXPORT_SYMBOL_GPL(kernfs_get); - -/** - * kernfs_put - put a reference count on a sysfs_dirent - * @sd: the target sysfs_dirent - * - * Put a reference count of @sd and destroy it if it reached zero. - */ -void kernfs_put(struct sysfs_dirent *sd) -{ - struct sysfs_dirent *parent_sd; - - if (!sd || !atomic_dec_and_test(&sd->s_count)) - return; - repeat: - /* Moving/renaming is always done while holding reference. - * sd->s_parent won't change beneath us. - */ - parent_sd = sd->s_parent; - - WARN(!(sd->s_flags & SYSFS_FLAG_REMOVED), - "sysfs: free using entry: %s/%s\n", - parent_sd ? parent_sd->s_name : "", sd->s_name); - - if (sysfs_type(sd) == SYSFS_KOBJ_LINK) - kernfs_put(sd->s_symlink.target_sd); - if (sysfs_type(sd) & SYSFS_COPY_NAME) - kfree(sd->s_name); - if (sd->s_iattr && sd->s_iattr->ia_secdata) - security_release_secctx(sd->s_iattr->ia_secdata, - sd->s_iattr->ia_secdata_len); - kfree(sd->s_iattr); - sysfs_free_ino(sd->s_ino); - kmem_cache_free(sysfs_dir_cachep, sd); - - sd = parent_sd; - if (sd && atomic_dec_and_test(&sd->s_count)) - goto repeat; -} -EXPORT_SYMBOL_GPL(kernfs_put); - -static int sysfs_dentry_delete(const struct dentry *dentry) -{ - struct sysfs_dirent *sd = dentry->d_fsdata; - return !(sd && !(sd->s_flags & SYSFS_FLAG_REMOVED)); -} - -static int sysfs_dentry_revalidate(struct dentry *dentry, unsigned int flags) -{ - struct sysfs_dirent *sd; - - if (flags & LOOKUP_RCU) - return -ECHILD; - - sd = dentry->d_fsdata; - mutex_lock(&sysfs_mutex); - - /* The sysfs dirent has been deleted */ - if (sd->s_flags & SYSFS_FLAG_REMOVED) - goto out_bad; - - /* The sysfs dirent has been moved? */ - if (dentry->d_parent->d_fsdata != sd->s_parent) - goto out_bad; - - /* The sysfs dirent has been renamed */ - if (strcmp(dentry->d_name.name, sd->s_name) != 0) - goto out_bad; - - /* The sysfs dirent has been moved to a different namespace */ - if (sd->s_parent && (sd->s_parent->s_flags & SYSFS_FLAG_NS) && - sysfs_info(dentry->d_sb)->ns != sd->s_ns) - goto out_bad; - - mutex_unlock(&sysfs_mutex); -out_valid: - return 1; -out_bad: - /* Remove the dentry from the dcache hashes. - * If this is a deleted dentry we use d_drop instead of d_delete - * so sysfs doesn't need to cope with negative dentries. - * - * If this is a dentry that has simply been renamed we - * use d_drop to remove it from the dcache lookup on its - * old parent. If this dentry persists later when a lookup - * is performed at its new name the dentry will be readded - * to the dcache hashes. - */ - mutex_unlock(&sysfs_mutex); - - /* If we have submounts we must allow the vfs caches - * to lie about the state of the filesystem to prevent - * leaks and other nasty things. - */ - if (check_submounts_and_drop(dentry) != 0) - goto out_valid; - - return 0; -} - -static void sysfs_dentry_release(struct dentry *dentry) -{ - kernfs_put(dentry->d_fsdata); -} - -const struct dentry_operations sysfs_dentry_ops = { - .d_revalidate = sysfs_dentry_revalidate, - .d_delete = sysfs_dentry_delete, - .d_release = sysfs_dentry_release, -}; - -struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type) -{ - char *dup_name = NULL; - struct sysfs_dirent *sd; - - if (type & SYSFS_COPY_NAME) { - name = dup_name = kstrdup(name, GFP_KERNEL); - if (!name) - return NULL; - } - - sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL); - if (!sd) - goto err_out1; - - if (sysfs_alloc_ino(&sd->s_ino)) - goto err_out2; - - atomic_set(&sd->s_count, 1); - atomic_set(&sd->s_active, 0); - - sd->s_name = name; - sd->s_mode = mode; - sd->s_flags = type | SYSFS_FLAG_REMOVED; - - return sd; - - err_out2: - kmem_cache_free(sysfs_dir_cachep, sd); - err_out1: - kfree(dup_name); - return NULL; -} - -/** - * sysfs_addrm_start - prepare for sysfs_dirent add/remove - * @acxt: pointer to sysfs_addrm_cxt to be used - * - * This function is called when the caller is about to add or remove - * sysfs_dirent. This function acquires sysfs_mutex. @acxt is used - * to keep and pass context to other addrm functions. - * - * LOCKING: - * Kernel thread context (may sleep). sysfs_mutex is locked on - * return. - */ -void sysfs_addrm_start(struct sysfs_addrm_cxt *acxt) - __acquires(sysfs_mutex) -{ - memset(acxt, 0, sizeof(*acxt)); - - mutex_lock(&sysfs_mutex); -} - -/** - * sysfs_add_one - add sysfs_dirent to parent without warning - * @acxt: addrm context to use - * @sd: sysfs_dirent to be added - * @parent_sd: the parent sysfs_dirent to add @sd to - * - * Get @parent_sd and set @sd->s_parent to it and increment nlink of - * the parent inode if @sd is a directory and link into the children - * list of the parent. - * - * This function should be called between calls to - * sysfs_addrm_start() and sysfs_addrm_finish() and should be - * passed the same @acxt as passed to sysfs_addrm_start(). - * - * LOCKING: - * Determined by sysfs_addrm_start(). - * - * RETURNS: - * 0 on success, -EEXIST if entry with the given name already - * exists. - */ -int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd, - struct sysfs_dirent *parent_sd) -{ - bool has_ns = parent_sd->s_flags & SYSFS_FLAG_NS; - struct sysfs_inode_attrs *ps_iattr; - int ret; - - if (has_ns != (bool)sd->s_ns) { - WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", - has_ns ? "required" : "invalid", - parent_sd->s_name, sd->s_name); - return -EINVAL; - } - - if (sysfs_type(parent_sd) != SYSFS_DIR) - return -EINVAL; - - sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); - sd->s_parent = parent_sd; - kernfs_get(parent_sd); - - ret = sysfs_link_sibling(sd); - if (ret) - return ret; - - /* Update timestamps on the parent */ - ps_iattr = parent_sd->s_iattr; - if (ps_iattr) { - struct iattr *ps_iattrs = &ps_iattr->ia_iattr; - ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; - } - - /* Mark the entry added into directory tree */ - sd->s_flags &= ~SYSFS_FLAG_REMOVED; - - return 0; -} - /** * sysfs_pathname - return full path to sysfs dirent * @sd: sysfs_dirent whose path we want @@ -510,181 +54,6 @@ void sysfs_warn_dup(struct sysfs_dirent *parent, const char *name) kfree(path); } -/** - * sysfs_remove_one - remove sysfs_dirent from parent - * @acxt: addrm context to use - * @sd: sysfs_dirent to be removed - * - * Mark @sd removed and drop nlink of parent inode if @sd is a - * directory. @sd is unlinked from the children list. - * - * This function should be called between calls to - * sysfs_addrm_start() and sysfs_addrm_finish() and should be - * passed the same @acxt as passed to sysfs_addrm_start(). - * - * LOCKING: - * Determined by sysfs_addrm_start(). - */ -static void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, - struct sysfs_dirent *sd) -{ - struct sysfs_inode_attrs *ps_iattr; - - /* - * Removal can be called multiple times on the same node. Only the - * first invocation is effective and puts the base ref. - */ - if (sd->s_flags & SYSFS_FLAG_REMOVED) - return; - - sysfs_unlink_sibling(sd); - - /* Update timestamps on the parent */ - ps_iattr = sd->s_parent->s_iattr; - if (ps_iattr) { - struct iattr *ps_iattrs = &ps_iattr->ia_iattr; - ps_iattrs->ia_ctime = ps_iattrs->ia_mtime = CURRENT_TIME; - } - - sd->s_flags |= SYSFS_FLAG_REMOVED; - sd->u.removed_list = acxt->removed; - acxt->removed = sd; -} - -/** - * sysfs_addrm_finish - finish up sysfs_dirent add/remove - * @acxt: addrm context to finish up - * - * Finish up sysfs_dirent add/remove. Resources acquired by - * sysfs_addrm_start() are released and removed sysfs_dirents are - * cleaned up. - * - * LOCKING: - * sysfs_mutex is released. - */ -void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt) - __releases(sysfs_mutex) -{ - /* release resources acquired by sysfs_addrm_start() */ - mutex_unlock(&sysfs_mutex); - - /* kill removed sysfs_dirents */ - while (acxt->removed) { - struct sysfs_dirent *sd = acxt->removed; - - acxt->removed = sd->u.removed_list; - - sysfs_deactivate(sd); - sysfs_unmap_bin_file(sd); - kernfs_put(sd); - } -} - -/** - * kernfs_find_ns - find sysfs_dirent with the given name - * @parent: sysfs_dirent to search under - * @name: name to look for - * @ns: the namespace tag to use - * - * Look for sysfs_dirent with name @name under @parent. Returns pointer to - * the found sysfs_dirent on success, %NULL on failure. - */ -static struct sysfs_dirent *kernfs_find_ns(struct sysfs_dirent *parent, - const unsigned char *name, - const void *ns) -{ - struct rb_node *node = parent->s_dir.children.rb_node; - bool has_ns = parent->s_flags & SYSFS_FLAG_NS; - unsigned int hash; - - lockdep_assert_held(&sysfs_mutex); - - if (has_ns != (bool)ns) { - WARN(1, KERN_WARNING "sysfs: ns %s in '%s' for '%s'\n", - has_ns ? "required" : "invalid", - parent->s_name, name); - return NULL; - } - - hash = sysfs_name_hash(name, ns); - while (node) { - struct sysfs_dirent *sd; - int result; - - sd = to_sysfs_dirent(node); - result = sysfs_name_compare(hash, name, ns, sd); - if (result < 0) - node = node->rb_left; - else if (result > 0) - node = node->rb_right; - else - return sd; - } - return NULL; -} - -/** - * kernfs_find_and_get_ns - find and get sysfs_dirent with the given name - * @parent: sysfs_dirent to search under - * @name: name to look for - * @ns: the namespace tag to use - * - * Look for sysfs_dirent with name @name under @parent and get a reference - * if found. This function may sleep and returns pointer to the found - * sysfs_dirent on success, %NULL on failure. - */ -struct sysfs_dirent *kernfs_find_and_get_ns(struct sysfs_dirent *parent, - const char *name, const void *ns) -{ - struct sysfs_dirent *sd; - - mutex_lock(&sysfs_mutex); - sd = kernfs_find_ns(parent, name, ns); - kernfs_get(sd); - mutex_unlock(&sysfs_mutex); - - return sd; -} -EXPORT_SYMBOL_GPL(kernfs_find_and_get_ns); - -/** - * 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; - struct sysfs_dirent *sd; - int rc; - - /* allocate */ - sd = sysfs_new_dirent(name, mode, SYSFS_DIR); - if (!sd) - return ERR_PTR(-ENOMEM); - - sd->s_ns = ns; - sd->priv = priv; - - /* link in */ - sysfs_addrm_start(&acxt); - rc = sysfs_add_one(&acxt, sd, parent); - sysfs_addrm_finish(&acxt); - - if (!rc) - return sd; - - kernfs_put(sd); - return ERR_PTR(rc); -} - /** * sysfs_create_dir_ns - create a directory for an object with a namespace tag * @kobj: object we're creating directory for @@ -715,177 +84,6 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) return 0; } -static struct dentry *sysfs_lookup(struct inode *dir, struct dentry *dentry, - unsigned int flags) -{ - struct dentry *ret = NULL; - struct dentry *parent = dentry->d_parent; - struct sysfs_dirent *parent_sd = parent->d_fsdata; - struct sysfs_dirent *sd; - struct inode *inode; - const void *ns = NULL; - - mutex_lock(&sysfs_mutex); - - if (parent_sd->s_flags & SYSFS_FLAG_NS) - ns = sysfs_info(dir->i_sb)->ns; - - sd = kernfs_find_ns(parent_sd, dentry->d_name.name, ns); - - /* no such entry */ - if (!sd) { - ret = ERR_PTR(-ENOENT); - goto out_unlock; - } - kernfs_get(sd); - dentry->d_fsdata = sd; - - /* attach dentry and inode */ - inode = sysfs_get_inode(dir->i_sb, sd); - if (!inode) { - ret = ERR_PTR(-ENOMEM); - goto out_unlock; - } - - /* instantiate and hash dentry */ - ret = d_materialise_unique(dentry, inode); - out_unlock: - mutex_unlock(&sysfs_mutex); - return ret; -} - -const struct inode_operations sysfs_dir_inode_operations = { - .lookup = sysfs_lookup, - .permission = sysfs_permission, - .setattr = sysfs_setattr, - .getattr = sysfs_getattr, - .setxattr = sysfs_setxattr, -}; - -static struct sysfs_dirent *sysfs_leftmost_descendant(struct sysfs_dirent *pos) -{ - struct sysfs_dirent *last; - - while (true) { - struct rb_node *rbn; - - last = pos; - - if (sysfs_type(pos) != SYSFS_DIR) - break; - - rbn = rb_first(&pos->s_dir.children); - if (!rbn) - break; - - pos = to_sysfs_dirent(rbn); - } - - return last; -} - -/** - * sysfs_next_descendant_post - find the next descendant for post-order walk - * @pos: the current position (%NULL to initiate traversal) - * @root: sysfs_dirent whose descendants to walk - * - * Find the next descendant to visit for post-order traversal of @root's - * descendants. @root is included in the iteration and the last node to be - * visited. - */ -static struct sysfs_dirent *sysfs_next_descendant_post(struct sysfs_dirent *pos, - struct sysfs_dirent *root) -{ - struct rb_node *rbn; - - lockdep_assert_held(&sysfs_mutex); - - /* if first iteration, visit leftmost descendant which may be root */ - if (!pos) - return sysfs_leftmost_descendant(root); - - /* if we visited @root, we're done */ - if (pos == root) - return NULL; - - /* if there's an unvisited sibling, visit its leftmost descendant */ - rbn = rb_next(&pos->s_rb); - if (rbn) - return sysfs_leftmost_descendant(to_sysfs_dirent(rbn)); - - /* no sibling left, visit parent */ - return pos->s_parent; -} - -static void __kernfs_remove(struct sysfs_addrm_cxt *acxt, - struct sysfs_dirent *sd) -{ - struct sysfs_dirent *pos, *next; - - if (!sd) - return; - - pr_debug("sysfs %s: removing\n", sd->s_name); - - next = NULL; - do { - pos = next; - next = sysfs_next_descendant_post(pos, sd); - if (pos) - sysfs_remove_one(acxt, pos); - } while (next); -} - -/** - * kernfs_remove - remove a sysfs_dirent recursively - * @sd: the sysfs_dirent to remove - * - * Remove @sd along with all its subdirectories and files. - */ -void kernfs_remove(struct sysfs_dirent *sd) -{ - struct sysfs_addrm_cxt acxt; - - sysfs_addrm_start(&acxt); - __kernfs_remove(&acxt, sd); - sysfs_addrm_finish(&acxt); -} - -/** - * kernfs_remove_by_name_ns - find a sysfs_dirent by name and remove it - * @dir_sd: parent of the target - * @name: name of the sysfs_dirent to remove - * @ns: namespace tag of the sysfs_dirent to remove - * - * Look for the sysfs_dirent with @name and @ns under @dir_sd and remove - * it. Returns 0 on success, -ENOENT if such entry doesn't exist. - */ -int kernfs_remove_by_name_ns(struct sysfs_dirent *dir_sd, const char *name, - const void *ns) -{ - struct sysfs_addrm_cxt acxt; - struct sysfs_dirent *sd; - - if (!dir_sd) { - WARN(1, KERN_WARNING "sysfs: can not remove '%s', no directory\n", - name); - return -ENOENT; - } - - sysfs_addrm_start(&acxt); - - sd = kernfs_find_ns(dir_sd, name, ns); - if (sd) - __kernfs_remove(&acxt, sd); - - sysfs_addrm_finish(&acxt); - - if (sd) - return 0; - else - return -ENOENT; -} - /** * sysfs_remove_dir - remove an object's directory. * @kobj: object. @@ -920,57 +118,6 @@ void sysfs_remove_dir(struct kobject *kobj) } } -/** - * kernfs_rename_ns - move and rename a kernfs_node - * @sd: target node - * @new_parent: new parent to put @sd under - * @new_name: new name - * @new_ns: new namespace tag - */ -int kernfs_rename_ns(struct sysfs_dirent *sd, struct sysfs_dirent *new_parent, - const char *new_name, const void *new_ns) -{ - int error; - - mutex_lock(&sysfs_mutex); - - error = 0; - if ((sd->s_parent == new_parent) && (sd->s_ns == new_ns) && - (strcmp(sd->s_name, new_name) == 0)) - goto out; /* nothing to rename */ - - error = -EEXIST; - if (kernfs_find_ns(new_parent, new_name, new_ns)) - goto out; - - /* rename sysfs_dirent */ - if (strcmp(sd->s_name, new_name) != 0) { - error = -ENOMEM; - new_name = kstrdup(new_name, GFP_KERNEL); - if (!new_name) - goto out; - - kfree(sd->s_name); - sd->s_name = new_name; - } - - /* - * Move to the appropriate place in the appropriate directories rbtree. - */ - sysfs_unlink_sibling(sd); - kernfs_get(new_parent); - kernfs_put(sd->s_parent); - sd->s_ns = new_ns; - sd->s_hash = sysfs_name_hash(sd->s_name, sd->s_ns); - sd->s_parent = new_parent; - sysfs_link_sibling(sd); - - error = 0; - out: - mutex_unlock(&sysfs_mutex); - return error; -} - int sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name, const void *new_ns) { @@ -991,136 +138,3 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, return kernfs_rename_ns(sd, new_parent_sd, sd->s_name, new_ns); } - -/** - * 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 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)); - sd->s_flags |= SYSFS_FLAG_NS; -} - -/* Relationship between s_mode and the DT_xxx types */ -static inline unsigned char dt_type(struct sysfs_dirent *sd) -{ - return (sd->s_mode >> 12) & 15; -} - -static int sysfs_dir_release(struct inode *inode, struct file *filp) -{ - kernfs_put(filp->private_data); - return 0; -} - -static struct sysfs_dirent *sysfs_dir_pos(const void *ns, - struct sysfs_dirent *parent_sd, loff_t hash, struct sysfs_dirent *pos) -{ - if (pos) { - int valid = !(pos->s_flags & SYSFS_FLAG_REMOVED) && - pos->s_parent == parent_sd && - hash == pos->s_hash; - kernfs_put(pos); - if (!valid) - pos = NULL; - } - if (!pos && (hash > 1) && (hash < INT_MAX)) { - struct rb_node *node = parent_sd->s_dir.children.rb_node; - while (node) { - pos = to_sysfs_dirent(node); - - if (hash < pos->s_hash) - node = node->rb_left; - else if (hash > pos->s_hash) - node = node->rb_right; - else - break; - } - } - /* Skip over entries in the wrong namespace */ - while (pos && pos->s_ns != ns) { - struct rb_node *node = rb_next(&pos->s_rb); - if (!node) - pos = NULL; - else - pos = to_sysfs_dirent(node); - } - return pos; -} - -static struct sysfs_dirent *sysfs_dir_next_pos(const void *ns, - struct sysfs_dirent *parent_sd, ino_t ino, struct sysfs_dirent *pos) -{ - pos = sysfs_dir_pos(ns, parent_sd, ino, pos); - if (pos) - do { - struct rb_node *node = rb_next(&pos->s_rb); - if (!node) - pos = NULL; - else - pos = to_sysfs_dirent(node); - } while (pos && pos->s_ns != ns); - return pos; -} - -static int sysfs_readdir(struct file *file, struct dir_context *ctx) -{ - struct dentry *dentry = file->f_path.dentry; - struct sysfs_dirent *parent_sd = dentry->d_fsdata; - struct sysfs_dirent *pos = file->private_data; - const void *ns = NULL; - - if (!dir_emit_dots(file, ctx)) - return 0; - mutex_lock(&sysfs_mutex); - - if (parent_sd->s_flags & SYSFS_FLAG_NS) - ns = sysfs_info(dentry->d_sb)->ns; - - for (pos = sysfs_dir_pos(ns, parent_sd, ctx->pos, pos); - pos; - pos = sysfs_dir_next_pos(ns, parent_sd, ctx->pos, pos)) { - const char *name = pos->s_name; - unsigned int type = dt_type(pos); - int len = strlen(name); - ino_t ino = pos->s_ino; - - ctx->pos = pos->s_hash; - file->private_data = pos; - kernfs_get(pos); - - mutex_unlock(&sysfs_mutex); - if (!dir_emit(ctx, name, len, ino, type)) - return 0; - mutex_lock(&sysfs_mutex); - } - mutex_unlock(&sysfs_mutex); - file->private_data = NULL; - ctx->pos = INT_MAX; - return 0; -} - -static loff_t sysfs_dir_llseek(struct file *file, loff_t offset, int whence) -{ - struct inode *inode = file_inode(file); - loff_t ret; - - mutex_lock(&inode->i_mutex); - ret = generic_file_llseek(file, offset, whence); - mutex_unlock(&inode->i_mutex); - - return ret; -} - -const struct file_operations sysfs_dir_operations = { - .read = generic_read_dir, - .iterate = sysfs_readdir, - .release = sysfs_dir_release, - .llseek = sysfs_dir_llseek, -}; -- cgit v1.2.3 From 061447a496b915f1dc8f8c645c6825f856d2bbac Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Thu, 28 Nov 2013 14:54:39 -0500 Subject: sysfs, kernfs: introduce sysfs_root_sd Currently, it's assumed that there's a single kernfs hierarchy in the system anchored at sysfs_root which is defined as a global struct. To allow other users of kernfs, this will be made dynamic. Introduce a new global variable sysfs_root_sd which points to &sysfs_root and convert all &sysfs_root users. This patch doesn't introduce any behavior difference. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index e5c4e7118050..2fea501889e7 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -68,7 +68,7 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) if (kobj->parent) parent_sd = kobj->parent->sd; else - parent_sd = &sysfs_root; + parent_sd = sysfs_root_sd; if (!parent_sd) return -ENOENT; @@ -134,7 +134,7 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, BUG_ON(!sd->s_parent); new_parent_sd = new_parent_kobj && new_parent_kobj->sd ? - new_parent_kobj->sd : &sysfs_root; + new_parent_kobj->sd : sysfs_root_sd; return kernfs_rename_ns(sd, new_parent_sd, sd->s_name, new_ns); } -- cgit v1.2.3 From 324a56e16e44baecac3ca799fd216154145c14bf Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 11 Dec 2013 14:11:53 -0500 Subject: kernfs: s/sysfs_dirent/kernfs_node/ and rename its friends accordingly kernfs has just been separated out from sysfs and we're already in full conflict mode. Nothing can make the situation any worse. Let's take the chance to name things properly. This patch performs the following renames. * s/sysfs_elem_dir/kernfs_elem_dir/ * s/sysfs_elem_symlink/kernfs_elem_symlink/ * s/sysfs_elem_attr/kernfs_elem_file/ * s/sysfs_dirent/kernfs_node/ * s/sd/kn/ in kernfs proper * s/parent_sd/parent/ * s/target_sd/target/ * s/dir_sd/parent/ * s/to_sysfs_dirent()/rb_to_kn()/ * misc renames of local vars when they conflict with the above Because md, mic and gpio dig into sysfs details, this patch ends up modifying them. All are sysfs_dirent renames and trivial. While we can avoid these by introducing a dummy wrapping struct sysfs_dirent around kernfs_node, given the limited usage outside kernfs and sysfs proper, I don't think such workaround is called for. This patch is strictly rename only and doesn't introduce any functional difference. - mic / gpio renames were missing. Spotted by kbuild test robot. Signed-off-by: Tejun Heo Cc: Neil Brown Cc: Linus Walleij Cc: Ashutosh Dixit Cc: kbuild test robot Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 66 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 33 insertions(+), 33 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 2fea501889e7..f1efe3df0de6 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -21,23 +21,23 @@ DEFINE_SPINLOCK(sysfs_symlink_target_lock); /** * sysfs_pathname - return full path to sysfs dirent - * @sd: sysfs_dirent whose path we want + * @kn: kernfs_node whose path we want * @path: caller allocated buffer of size PATH_MAX * * Gives the name "/" to the sysfs_root entry; any path returned * is relative to wherever sysfs is mounted. */ -static char *sysfs_pathname(struct sysfs_dirent *sd, char *path) +static char *sysfs_pathname(struct kernfs_node *kn, char *path) { - if (sd->s_parent) { - sysfs_pathname(sd->s_parent, path); + if (kn->s_parent) { + sysfs_pathname(kn->s_parent, path); strlcat(path, "/", PATH_MAX); } - strlcat(path, sd->s_name, PATH_MAX); + strlcat(path, kn->s_name, PATH_MAX); return path; } -void sysfs_warn_dup(struct sysfs_dirent *parent, const char *name) +void sysfs_warn_dup(struct kernfs_node *parent, const char *name) { char *path; @@ -61,26 +61,26 @@ void sysfs_warn_dup(struct sysfs_dirent *parent, const char *name) */ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) { - struct sysfs_dirent *parent_sd, *sd; + struct kernfs_node *parent, *kn; BUG_ON(!kobj); if (kobj->parent) - parent_sd = kobj->parent->sd; + parent = kobj->parent->sd; else - parent_sd = sysfs_root_sd; + parent = sysfs_root_kn; - if (!parent_sd) + if (!parent) return -ENOENT; - 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); + kn = kernfs_create_dir_ns(parent, kobject_name(kobj), kobj, ns); + if (IS_ERR(kn)) { + if (PTR_ERR(kn) == -EEXIST) + sysfs_warn_dup(parent, kobject_name(kobj)); + return PTR_ERR(kn); } - kobj->sd = sd; + kobj->sd = kn; return 0; } @@ -94,47 +94,47 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) */ void sysfs_remove_dir(struct kobject *kobj) { - struct sysfs_dirent *sd = kobj->sd; + struct kernfs_node *kn = kobj->sd; /* * In general, kboject owner is responsible for ensuring removal * doesn't race with other operations and sysfs doesn't provide any * protection; however, when @kobj is used as a symlink target, the * symlinking entity usually doesn't own @kobj and thus has no - * control over removal. @kobj->sd may be removed anytime and - * symlink code may end up dereferencing an already freed sd. + * control over removal. @kobj->sd may be removed anytime + * and symlink code may end up dereferencing an already freed node. * - * sysfs_symlink_target_lock synchronizes @kobj->sd disassociation - * against symlink operations so that symlink code can safely - * dereference @kobj->sd. + * sysfs_symlink_target_lock synchronizes @kobj->sd + * disassociation against symlink operations so that symlink code + * can safely dereference @kobj->sd. */ spin_lock(&sysfs_symlink_target_lock); kobj->sd = NULL; spin_unlock(&sysfs_symlink_target_lock); - if (sd) { - WARN_ON_ONCE(sysfs_type(sd) != SYSFS_DIR); - kernfs_remove(sd); + if (kn) { + WARN_ON_ONCE(sysfs_type(kn) != SYSFS_DIR); + kernfs_remove(kn); } } int sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name, const void *new_ns) { - struct sysfs_dirent *parent_sd = kobj->sd->s_parent; + struct kernfs_node *parent = kobj->sd->s_parent; - return kernfs_rename_ns(kobj->sd, parent_sd, new_name, new_ns); + return kernfs_rename_ns(kobj->sd, parent, new_name, new_ns); } int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, const void *new_ns) { - struct sysfs_dirent *sd = kobj->sd; - struct sysfs_dirent *new_parent_sd; + struct kernfs_node *kn = kobj->sd; + struct kernfs_node *new_parent; - BUG_ON(!sd->s_parent); - new_parent_sd = new_parent_kobj && new_parent_kobj->sd ? - new_parent_kobj->sd : sysfs_root_sd; + BUG_ON(!kn->s_parent); + new_parent = new_parent_kobj && new_parent_kobj->sd ? + new_parent_kobj->sd : sysfs_root_kn; - return kernfs_rename_ns(sd, new_parent_sd, sd->s_name, new_ns); + return kernfs_rename_ns(kn, new_parent, kn->s_name, new_ns); } -- cgit v1.2.3 From adc5e8b58f4886d45f79f4ff41a09001a76a6b12 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 11 Dec 2013 14:11:54 -0500 Subject: kernfs: drop s_ prefix from kernfs_node members kernfs has just been separated out from sysfs and we're already in full conflict mode. Nothing can make the situation any worse. Let's take the chance to name things properly. s_ prefix for kernfs members is used inconsistently and a misnomer now. It's not like kernfs_node is used widely across the kernel making the ability to grep for the members particularly useful. Let's just drop the prefix. This patch is strictly rename only and doesn't introduce any functional difference. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index f1efe3df0de6..4a800017558d 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -29,11 +29,11 @@ DEFINE_SPINLOCK(sysfs_symlink_target_lock); */ static char *sysfs_pathname(struct kernfs_node *kn, char *path) { - if (kn->s_parent) { - sysfs_pathname(kn->s_parent, path); + if (kn->parent) { + sysfs_pathname(kn->parent, path); strlcat(path, "/", PATH_MAX); } - strlcat(path, kn->s_name, PATH_MAX); + strlcat(path, kn->name, PATH_MAX); return path; } @@ -121,7 +121,7 @@ void sysfs_remove_dir(struct kobject *kobj) int sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name, const void *new_ns) { - struct kernfs_node *parent = kobj->sd->s_parent; + struct kernfs_node *parent = kobj->sd->parent; return kernfs_rename_ns(kobj->sd, parent, new_name, new_ns); } @@ -132,9 +132,9 @@ int sysfs_move_dir_ns(struct kobject *kobj, struct kobject *new_parent_kobj, struct kernfs_node *kn = kobj->sd; struct kernfs_node *new_parent; - BUG_ON(!kn->s_parent); + BUG_ON(!kn->parent); new_parent = new_parent_kobj && new_parent_kobj->sd ? new_parent_kobj->sd : sysfs_root_kn; - return kernfs_rename_ns(kn, new_parent, kn->s_name, new_ns); + return kernfs_rename_ns(kn, new_parent, kn->name, new_ns); } -- cgit v1.2.3 From df23fc39bce03bb26e63bea57fc5f5bf6882d74b Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 11 Dec 2013 14:11:56 -0500 Subject: kernfs: s/sysfs/kernfs/ in constants kernfs has just been separated out from sysfs and we're already in full conflict mode. Nothing can make the situation any worse. Let's take the chance to name things properly. This patch performs the following renames. * s/SYSFS_DIR/KERNFS_DIR/ * s/SYSFS_KOBJ_ATTR/KERNFS_FILE/ * s/SYSFS_KOBJ_LINK/KERNFS_LINK/ * s/SYSFS_{TYPE_FLAGS}/KERNFS_{TYPE_FLAGS}/ * s/SYSFS_FLAG_{FLAG}/KERNFS_{FLAG}/ * s/sysfs_type()/kernfs_type()/ * s/SD_DEACTIVATED_BIAS/KN_DEACTIVATED_BIAS/ This patch is strictly rename only and doesn't introduce any functional difference. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index 4a800017558d..aa007401bfc9 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -113,7 +113,7 @@ void sysfs_remove_dir(struct kobject *kobj) spin_unlock(&sysfs_symlink_target_lock); if (kn) { - WARN_ON_ONCE(sysfs_type(kn) != SYSFS_DIR); + WARN_ON_ONCE(kernfs_type(kn) != KERNFS_DIR); kernfs_remove(kn); } } -- cgit v1.2.3 From bb8b9d095c5c56cce99576cfef0cf9b989f7120d Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 11 Dec 2013 16:02:55 -0500 Subject: kernfs: add @mode to kernfs_create_dir[_ns]() sysfs assumed 0755 for all newly created directories and kernfs inherited it. This assumption is unnecessarily restrictive and inconsistent with kernfs_create_file[_ns](). This patch adds @mode parameter to kernfs_create_dir[_ns]() and update uses in sysfs accordingly. Among others, this will be useful for implementations of the planned ->mkdir() method. This patch doesn't introduce any behavior differences. Signed-off-by: Tejun Heo Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/dir.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/sysfs/dir.c') diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c index aa007401bfc9..ee0d761c3179 100644 --- a/fs/sysfs/dir.c +++ b/fs/sysfs/dir.c @@ -73,7 +73,8 @@ int sysfs_create_dir_ns(struct kobject *kobj, const void *ns) if (!parent) return -ENOENT; - kn = kernfs_create_dir_ns(parent, kobject_name(kobj), kobj, ns); + kn = kernfs_create_dir_ns(parent, kobject_name(kobj), + S_IRWXU | S_IRUGO | S_IXUGO, kobj, ns); if (IS_ERR(kn)) { if (PTR_ERR(kn) == -EEXIST) sysfs_warn_dup(parent, kobject_name(kobj)); -- cgit v1.2.3