sysfs, kernfs: make sysfs_dirent definition public
sysfs_dirent includes some information which should be available to
kernfs users - the type, flags, name and parent pointer. This patch
moves sysfs_dirent definition from kernfs/kernfs-internal.h to
include/linux/kernfs.h so that kernfs users can access them.
The type part of flags is exported as enum kernfs_node_type, the flags
kernfs_node_flag, sysfs_type() and kernfs_enable_ns() are moved to
include/linux/kernfs.h and the former is updated to return the enum
type. sysfs_dirent->s_parent and ->s_name are marked explicitly as
public.
This patch doesn't introduce any functional changes.
v2: Flags exported too and kernfs_enable_ns() definition moved.
v3: While moving kernfs_enable_ns() to include/linux/kernfs.h, v1 and
v2 put the definition outside CONFIG_SYSFS replacing the dummy
implementation with the actual implementation too. Unfortunately,
this can lead to oops when !CONFIG_SYSFS because
kernfs_enable_ns() may be called on a NULL @sd and now tries to
dereference @sd instead of not doing anything. This issue was
reported by Yuanhan Liu.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/fs/kernfs/kernfs-internal.h b/fs/kernfs/kernfs-internal.h
index ced0d6d..f33a784 100644
--- a/fs/kernfs/kernfs-internal.h
+++ b/fs/kernfs/kernfs-internal.h
@@ -13,102 +13,19 @@
#include <linux/lockdep.h>
#include <linux/fs.h>
-#include <linux/rbtree.h>
#include <linux/mutex.h>
#include <linux/kernfs.h>
-struct sysfs_open_dirent;
-
-/* type-specific structures for sysfs_dirent->s_* union members */
-struct sysfs_elem_dir {
- unsigned long subdirs;
- /* children rbtree starts here and goes through sd->s_rb */
- struct rb_root children;
-
- /*
- * The kernfs hierarchy this directory belongs to. This fits
- * better directly in sysfs_dirent but is here to save space.
- */
- struct kernfs_root *root;
-};
-
-struct sysfs_elem_symlink {
- struct sysfs_dirent *target_sd;
-};
-
-struct sysfs_elem_attr {
- const struct kernfs_ops *ops;
- struct sysfs_open_dirent *open;
- loff_t size;
-};
-
struct sysfs_inode_attrs {
struct iattr ia_iattr;
void *ia_secdata;
u32 ia_secdata_len;
};
-/*
- * sysfs_dirent - the building block of sysfs hierarchy. Each and
- * every sysfs node is represented by single sysfs_dirent.
- *
- * As long as s_count reference is held, the sysfs_dirent itself is
- * accessible. Dereferencing s_elem or any other outer entity
- * requires s_active reference.
- */
-struct sysfs_dirent {
- atomic_t s_count;
- atomic_t s_active;
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
- struct lockdep_map dep_map;
-#endif
- struct sysfs_dirent *s_parent;
- const char *s_name;
-
- struct rb_node s_rb;
-
- union {
- struct completion *completion;
- struct sysfs_dirent *removed_list;
- } u;
-
- const void *s_ns; /* namespace tag */
- unsigned int s_hash; /* ns + name hash */
- union {
- struct sysfs_elem_dir s_dir;
- struct sysfs_elem_symlink s_symlink;
- struct sysfs_elem_attr s_attr;
- };
-
- void *priv;
-
- unsigned short s_flags;
- umode_t s_mode;
- unsigned int s_ino;
- struct sysfs_inode_attrs *s_iattr;
-};
-
#define SD_DEACTIVATED_BIAS INT_MIN
-#define SYSFS_TYPE_MASK 0x000f
-#define SYSFS_DIR 0x0001
-#define SYSFS_KOBJ_ATTR 0x0002
-#define SYSFS_KOBJ_LINK 0x0004
-#define SYSFS_COPY_NAME (SYSFS_DIR | SYSFS_KOBJ_LINK)
-#define SYSFS_ACTIVE_REF SYSFS_KOBJ_ATTR
-
-#define SYSFS_FLAG_MASK ~SYSFS_TYPE_MASK
-#define SYSFS_FLAG_REMOVED 0x0010
-#define SYSFS_FLAG_NS 0x0020
-#define SYSFS_FLAG_HAS_SEQ_SHOW 0x0040
-#define SYSFS_FLAG_HAS_MMAP 0x0080
-#define SYSFS_FLAG_LOCKDEP 0x0100
-
-static inline unsigned int sysfs_type(struct sysfs_dirent *sd)
-{
- return sd->s_flags & SYSFS_TYPE_MASK;
-}
+/* SYSFS_TYPE_MASK and types are defined in include/linux/kernfs.h */
/**
* kernfs_root - find out the kernfs_root a sysfs_dirent belongs to