[PATCH 01/34] sysfs, kernfs: replace sysfs_dirent->s_dir.kobj and ->s_attr.[bin_]attr with ->priv

Tejun Heo
2013-11-28T19:55:01Z

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 <tj@kernel.org>
---
fs/sysfs/dir.c | 2 +-
fs/sysfs/file.c | 26 +++++++++++++-------------
fs/sysfs/inode.c | 2 +-
fs/sysfs/symlink.c | 2 +-
fs/sysfs/sysfs.h | 13 +++++--------
5 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/fs/sysfs/dir.c b/fs/sysfs/dir.c
index 5ba8966..aeb08bd 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);
diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 0f3f0a2..9b58d87 100644
--- a/fs/sysfs/file.c
+++ b/fs/sysfs/file.c
@@ -74,7 +74,7 @@ static struct sysfs_open_file *sysfs_of(struct file *file)
*/
static const struct sysfs_ops *sysfs_file_ops(struct sysfs_dirent *sd)
{
- struct kobject *kobj = sd->s_parent->s_dir.kobj;
+ struct kobject *kobj = sd->s_parent->priv;

if (!sysfs_ignore_lockdep(sd))
lockdep_assert_held(sd);
@@ -89,7 +89,7 @@ static const struct sysfs_ops *sysfs_file_ops(struct sysfs_dirent *sd)
static int sysfs_seq_show(struct seq_file *sf, void *v)
{
struct sysfs_open_file *of = sf->private;
- struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
+ struct kobject *kobj = of->sd->s_parent->priv;
const struct sysfs_ops *ops;
char *buf;
ssize_t count;
@@ -120,7 +120,7 @@ static int sysfs_seq_show(struct seq_file *sf, void *v)
*/
ops = sysfs_file_ops(of->sd);
if (ops->show)
- count = ops->show(kobj, of->sd->s_attr.attr, buf);
+ count = ops->show(kobj, of->sd->priv, buf);
else
count = 0;

@@ -154,8 +154,8 @@ static ssize_t sysfs_bin_read(struct file *file, char __user *userbuf,
size_t bytes, loff_t *off)
{
struct sysfs_open_file *of = sysfs_of(file);
- struct bin_attribute *battr = of->sd->s_attr.bin_attr;
- struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
+ struct bin_attribute *battr = of->sd->priv;
+ struct kobject *kobj = of->sd->s_parent->priv;
loff_t size = file_inode(file)->i_size;
int count = min_t(size_t, bytes, PAGE_SIZE);
loff_t offs = *off;
@@ -221,7 +221,7 @@ static ssize_t sysfs_bin_read(struct file *file, char __user *userbuf,
static int flush_write_buffer(struct sysfs_open_file *of, char *buf, loff_t off,
size_t count)
{
- struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
+ struct kobject *kobj = of->sd->s_parent->priv;
int rc = 0;

/*
@@ -236,7 +236,7 @@ static int flush_write_buffer(struct sysfs_open_file *of, char *buf, loff_t off,
}

if (sysfs_is_bin(of->sd)) {
- struct bin_attribute *battr = of->sd->s_attr.bin_attr;
+ struct bin_attribute *battr = of->sd->priv;

rc = -EIO;
if (battr->write)
@@ -245,7 +245,7 @@ static int flush_write_buffer(struct sysfs_open_file *of, char *buf, loff_t off,
} else {
const struct sysfs_ops *ops = sysfs_file_ops(of->sd);

- rc = ops->store(kobj, of->sd->s_attr.attr, buf, count);
+ rc = ops->store(kobj, of->sd->priv, buf, count);
}

sysfs_put_active(of->sd);
@@ -466,8 +466,8 @@ static const struct vm_operations_struct sysfs_bin_vm_ops = {
static int sysfs_bin_mmap(struct file *file, struct vm_area_struct *vma)
{
struct sysfs_open_file *of = sysfs_of(file);
- struct bin_attribute *battr = of->sd->s_attr.bin_attr;
- struct kobject *kobj = of->sd->s_parent->s_dir.kobj;
+ struct bin_attribute *battr = of->sd->priv;
+ struct kobject *kobj = of->sd->s_parent->priv;
int rc;

mutex_lock(&of->mutex);
@@ -607,7 +607,7 @@ static void sysfs_put_open_dirent(struct sysfs_dirent *sd,
static int sysfs_open_file(struct inode *inode, struct file *file)
{
struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
- struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
+ struct kobject *kobj = attr_sd->s_parent->priv;
struct sysfs_open_file *of;
bool has_read, has_write, has_mmap;
int error = -EACCES;
@@ -617,7 +617,7 @@ static int sysfs_open_file(struct inode *inode, struct file *file)
return -ENODEV;

if (sysfs_is_bin(attr_sd)) {
- struct bin_attribute *battr = attr_sd->s_attr.bin_attr;
+ struct bin_attribute *battr = attr_sd->priv;

has_read = battr->read || battr->mmap;
has_write = battr->write || battr->mmap;
@@ -848,7 +848,7 @@ int sysfs_add_file_mode_ns(struct sysfs_dirent *dir_sd,
return -ENOMEM;

sd->s_ns = ns;
- sd->s_attr.attr = (void *)attr;
+ sd->priv = (void *)attr;
sysfs_dirent_init_lockdep(sd);

sysfs_addrm_start(&acxt);
diff --git a/fs/sysfs/inode.c b/fs/sysfs/inode.c
index 5f7e2af..81cc858 100644
--- a/fs/sysfs/inode.c
+++ b/fs/sysfs/inode.c
@@ -275,7 +275,7 @@ static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
inode->i_fop = &sysfs_file_operations;
break;
case SYSFS_KOBJ_BIN_ATTR:
- bin_attr = sd->s_attr.bin_attr;
+ bin_attr = sd->priv;
inode->i_size = bin_attr->size;
inode->i_fop = &sysfs_bin_operations;
break;
diff --git a/fs/sysfs/symlink.c b/fs/sysfs/symlink.c
index 0922c53..352fbbb 100644
--- a/fs/sysfs/symlink.c
+++ b/fs/sysfs/symlink.c
@@ -223,7 +223,7 @@ int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *targ,
result = -EINVAL;
if (sysfs_type(sd) != SYSFS_KOBJ_LINK)
goto out;
- if (sd->s_symlink.target_sd->s_dir.kobj != targ)
+ if (sd->s_symlink.target_sd->priv != targ)
goto out;

result = kernfs_rename_ns(sd, parent_sd, new, new_ns);
diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h
index 2abccfd..a6f3fa3 100644
--- a/fs/sysfs/sysfs.h
+++ b/fs/sysfs/sysfs.h
@@ -17,8 +17,6 @@ struct sysfs_open_dirent;

/* type-specific structures for sysfs_dirent->s_* union members */
struct sysfs_elem_dir {
- struct kobject *kobj;
-
unsigned long subdirs;
/* children rbtree starts here and goes through sd->s_rb */
struct rb_root children;
@@ -29,10 +27,6 @@ struct sysfs_elem_symlink {
};

struct sysfs_elem_attr {
- union {
- struct attribute *attr;
- struct bin_attribute *bin_attr;
- };
struct sysfs_open_dirent *open;
};

@@ -74,6 +68,8 @@ struct sysfs_dirent {
struct sysfs_elem_attr s_attr;
};

+ void *priv;
+
unsigned short s_flags;
umode_t s_mode;
unsigned int s_ino;
@@ -103,7 +99,7 @@ static inline unsigned int sysfs_type(struct sysfs_dirent *sd)

#define sysfs_dirent_init_lockdep(sd) \
do { \
- struct attribute *attr = sd->s_attr.attr; \
+ struct attribute *attr = sd->priv; \
struct lock_class_key *key = attr->key; \
if (!key) \
key = &attr->skey; \
@@ -114,10 +110,11 @@ do { \
/* Test for attributes that want to ignore lockdep for read-locking */
static inline bool sysfs_ignore_lockdep(struct sysfs_dirent *sd)
{
+ struct attribute *attr = sd->priv;
int type = sysfs_type(sd);

return (type == SYSFS_KOBJ_ATTR || type == SYSFS_KOBJ_BIN_ATTR) &&
- sd->s_attr.attr->ignore_lockdep;
+ attr->ignore_lockdep;
}

#else
--
1.8.4.2