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sysfs: reorganize sysfs_new_indoe() and sysfs_create()

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Reorganize/clean up sysfs_new_inode() and sysfs_create().

* sysfs_init_inode() is separated out from sysfs_new_inode() and is
  responsible for basic initialization.
* sysfs_instantiate() replaces the last step of sysfs_create() and is
  responsible for dentry instantitaion.
* type-specific initialization is moved out to the callers.
* mode is specified only once when creating a sysfs_dirent.
* spurious list_del_init(&sd->s_sibling) dropped from create_dir()

This change is to

* prepare for inode allocation fix.
* separate alloc and init code for synchronization update.
* make dentry/inode initialization more flexible for later changes.

This patch doesn't introduce visible behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Tejun Heo
2007-06-14 03:45:17 +09:00
committed by Greg Kroah-Hartman
parent 7f7cfffe60
commit fc9f54b998
4 changed files with 116 additions and 142 deletions
Download Patch File Download Diff File Expand all files Collapse all files

130
fs/sysfs/dir.c
View File

@@ -191,39 +191,18 @@ int sysfs_dirent_exist(struct sysfs_dirent *parent_sd,
return 0;
}
static int init_dir(struct inode * inode)
{
inode->i_op = &sysfs_dir_inode_operations;
inode->i_fop = &sysfs_dir_operations;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
return 0;
}
static int init_file(struct inode * inode)
{
inode->i_size = PAGE_SIZE;
inode->i_fop = &sysfs_file_operations;
return 0;
}
static int init_symlink(struct inode * inode)
{
inode->i_op = &sysfs_symlink_inode_operations;
return 0;
}
static int create_dir(struct kobject *kobj, struct dentry *parent,
const char *name, struct dentry **p_dentry)
{
int error;
umode_t mode = S_IFDIR| S_IRWXU | S_IRUGO | S_IXUGO;
struct dentry *dentry;
struct inode *inode;
struct sysfs_dirent *sd;
mutex_lock(&parent->d_inode->i_mutex);
/* allocate */
dentry = lookup_one_len(name, parent, strlen(name));
if (IS_ERR(dentry)) {
error = PTR_ERR(dentry);
@@ -231,7 +210,7 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
}
error = -EEXIST;
if (sysfs_dirent_exist(parent->d_fsdata, name))
if (dentry->d_inode)
goto out_dput;
error = -ENOMEM;
@@ -240,19 +219,31 @@ static int create_dir(struct kobject *kobj, struct dentry *parent,
goto out_drop;
sd->s_elem.dir.kobj = kobj;
error = sysfs_create(sd, dentry, mode, init_dir);
if (error)
inode = sysfs_new_inode(sd);
if (!inode)
goto out_sput;
inode->i_op = &sysfs_dir_inode_operations;
inode->i_fop = &sysfs_dir_operations;
/* directory inodes start off with i_nlink == 2 (for "." entry) */
inc_nlink(inode);
/* link in */
error = -EEXIST;
if (sysfs_dirent_exist(parent->d_fsdata, name))
goto out_iput;
sysfs_instantiate(dentry, inode);
inc_nlink(parent->d_inode);
sysfs_attach_dirent(sd, parent->d_fsdata, dentry);
*p_dentry = dentry;
error = 0;
goto out_dput;
goto out_unlock; /* pin directory dentry in core */
out_iput:
iput(inode);
out_sput:
list_del_init(&sd->s_sibling);
sysfs_put(sd);
out_drop:
d_drop(dentry);
@@ -298,71 +289,46 @@ int sysfs_create_dir(struct kobject * kobj, struct dentry *shadow_parent)
return error;
}
/* attaches attribute's sysfs_dirent to the dentry corresponding to the
* attribute file
*/
static int sysfs_attach_attr(struct sysfs_dirent * sd, struct dentry * dentry)
{
struct attribute * attr = NULL;
struct bin_attribute * bin_attr = NULL;
int (* init) (struct inode *) = NULL;
int error = 0;
if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) {
bin_attr = sd->s_elem.bin_attr.bin_attr;
attr = &bin_attr->attr;
} else {
attr = sd->s_elem.attr.attr;
init = init_file;
}
error = sysfs_create(sd, dentry,
(attr->mode & S_IALLUGO) | S_IFREG, init);
if (error)
return error;
if (bin_attr) {
dentry->d_inode->i_size = bin_attr->size;
dentry->d_inode->i_fop = &bin_fops;
}
sysfs_attach_dentry(sd, dentry);
return 0;
}
static int sysfs_attach_link(struct sysfs_dirent * sd, struct dentry * dentry)
{
int err;
err = sysfs_create(sd, dentry, S_IFLNK|S_IRWXUGO, init_symlink);
if (!err)
sysfs_attach_dentry(sd, dentry);
return err;
}
static struct dentry * sysfs_lookup(struct inode *dir, struct dentry *dentry,
struct nameidata *nd)
{
struct sysfs_dirent * parent_sd = dentry->d_parent->d_fsdata;
struct sysfs_dirent * sd;
int err = 0;
struct inode *inode;
int found = 0;
list_for_each_entry(sd, &parent_sd->s_children, s_sibling) {
if (sd->s_type & SYSFS_NOT_PINNED) {
if (strcmp(sd->s_name, dentry->d_name.name))
continue;
if (sd->s_type & SYSFS_KOBJ_LINK)
err = sysfs_attach_link(sd, dentry);
else
err = sysfs_attach_attr(sd, dentry);
if ((sd->s_type & SYSFS_NOT_PINNED) &&
!strcmp(sd->s_name, dentry->d_name.name)) {
found = 1;
break;
}
}
return ERR_PTR(err);
/* no such entry */
if (!found)
return NULL;
/* attach dentry and inode */
inode = sysfs_new_inode(sd);
if (!inode)
return ERR_PTR(-ENOMEM);
/* initialize inode according to type */
if (sd->s_type & SYSFS_KOBJ_ATTR) {
inode->i_size = PAGE_SIZE;
inode->i_fop = &sysfs_file_operations;
} else if (sd->s_type & SYSFS_KOBJ_BIN_ATTR) {
struct bin_attribute *bin_attr = sd->s_elem.bin_attr.bin_attr;
inode->i_size = bin_attr->size;
inode->i_fop = &bin_fops;
} else if (sd->s_type & SYSFS_KOBJ_LINK)
inode->i_op = &sysfs_symlink_inode_operations;
sysfs_instantiate(dentry, inode);
sysfs_attach_dentry(sd, dentry);
return NULL;
}
const struct inode_operations sysfs_dir_inode_operations = {