#include <linux/namei.h>
#include <linux/idr.h>
#include <linux/completion.h>
-#include <asm/semaphore.h>
+#include <linux/mutex.h>
#include "sysfs.h"
DEFINE_MUTEX(sysfs_mutex);
* Locking:
* mutex_lock(sysfs_mutex)
*/
-void sysfs_link_sibling(struct sysfs_dirent *sd)
+static void sysfs_link_sibling(struct sysfs_dirent *sd)
{
struct sysfs_dirent *parent_sd = sd->s_parent;
* Locking:
* mutex_lock(sysfs_mutex)
*/
-void sysfs_unlink_sibling(struct sysfs_dirent *sd)
+static void sysfs_unlink_sibling(struct sysfs_dirent *sd)
{
struct sysfs_dirent **pos;
/* look it up */
parent_dentry = dentry;
+ mutex_lock(&parent_dentry->d_inode->i_mutex);
dentry = lookup_one_len_kern(cur->s_name, parent_dentry,
strlen(cur->s_name));
+ mutex_unlock(&parent_dentry->d_inode->i_mutex);
dput(parent_dentry);
if (IS_ERR(dentry)) {
struct sysfs_dirent *sysfs_new_dirent(const char *name, umode_t mode, int type)
{
char *dup_name = NULL;
- struct sysfs_dirent *sd = NULL;
+ struct sysfs_dirent *sd;
if (type & SYSFS_COPY_NAME) {
name = dup_name = kstrdup(name, GFP_KERNEL);
if (!name)
- goto err_out;
+ return NULL;
}
sd = kmem_cache_zalloc(sysfs_dir_cachep, GFP_KERNEL);
if (!sd)
- goto err_out;
+ goto err_out1;
if (sysfs_alloc_ino(&sd->s_ino))
- goto err_out;
+ goto err_out2;
atomic_set(&sd->s_count, 1);
atomic_set(&sd->s_active, 0);
return sd;
- err_out:
- kfree(dup_name);
+ err_out2:
kmem_cache_free(sysfs_dir_cachep, sd);
+ err_out1:
+ kfree(dup_name);
return NULL;
}
*
* LOCKING:
* Determined by sysfs_addrm_start().
+ *
+ * RETURNS:
+ * 0 on success, -EEXIST if entry with the given name already
+ * exists.
*/
-void sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
+int sysfs_add_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
+ if (sysfs_find_dirent(acxt->parent_sd, sd->s_name))
+ return -EEXIST;
+
sd->s_parent = sysfs_get(acxt->parent_sd);
if (sysfs_type(sd) == SYSFS_DIR && acxt->parent_inode)
inc_nlink(acxt->parent_inode);
acxt->cnt++;
+
+ sysfs_link_sibling(sd);
+
+ return 0;
}
/**
*/
void sysfs_remove_one(struct sysfs_addrm_cxt *acxt, struct sysfs_dirent *sd)
{
- BUG_ON(sd->s_sibling || (sd->s_flags & SYSFS_FLAG_REMOVED));
+ BUG_ON(sd->s_flags & SYSFS_FLAG_REMOVED);
+
+ sysfs_unlink_sibling(sd);
sd->s_flags |= SYSFS_FLAG_REMOVED;
sd->s_sibling = acxt->removed;
spin_unlock(&dcache_lock);
spin_unlock(&sysfs_assoc_lock);
- /* dentries for shadowed inodes are pinned, unpin */
- if (dentry && sysfs_is_shadowed_inode(dentry->d_inode))
- dput(dentry);
dput(dentry);
/* adjust nlink and update timestamp */
*
* LOCKING:
* All mutexes acquired by sysfs_addrm_start() are released.
- *
- * RETURNS:
- * Number of added/removed sysfs_dirents since sysfs_addrm_start().
*/
-int sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
+void sysfs_addrm_finish(struct sysfs_addrm_cxt *acxt)
{
/* release resources acquired by sysfs_addrm_start() */
mutex_unlock(&sysfs_mutex);
sysfs_deactivate(sd);
sysfs_put(sd);
}
-
- return acxt->cnt;
}
/**
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);
/* link in */
sysfs_addrm_start(&acxt, parent_sd);
- if (!sysfs_find_dirent(parent_sd, name)) {
- sysfs_add_one(&acxt, sd);
- sysfs_link_sibling(sd);
- }
- if (sysfs_addrm_finish(&acxt)) {
+ rc = sysfs_add_one(&acxt, sd);
+ sysfs_addrm_finish(&acxt);
+
+ if (rc == 0)
*p_sd = sd;
- return 0;
- }
+ else
+ sysfs_put(sd);
- sysfs_put(sd);
- return -EEXIST;
+ return rc;
}
int sysfs_create_subdir(struct kobject *kobj, const char *name,
/**
* sysfs_create_dir - create a directory for an object.
* @kobj: object we're creating directory for.
- * @shadow_parent: parent object.
*/
-int sysfs_create_dir(struct kobject *kobj,
- struct sysfs_dirent *shadow_parent_sd)
+int sysfs_create_dir(struct kobject * kobj)
{
struct sysfs_dirent *parent_sd, *sd;
int error = 0;
BUG_ON(!kobj);
- if (shadow_parent_sd)
- parent_sd = shadow_parent_sd;
- else if (kobj->parent)
+ if (kobj->parent)
parent_sd = kobj->parent->sd;
else if (sysfs_mount && sysfs_mount->mnt_sb)
parent_sd = sysfs_mount->mnt_sb->s_root->d_fsdata;
return error;
}
-static int sysfs_count_nlink(struct sysfs_dirent *sd)
-{
- struct sysfs_dirent *child;
- int nr = 0;
-
- for (child = sd->s_children; child; child = child->s_sibling)
- if (sysfs_type(child) == SYSFS_DIR)
- nr++;
- return nr + 2;
-}
-
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;
- struct bin_attribute *bin_attr;
+ struct dentry *ret = NULL;
+ struct sysfs_dirent *parent_sd = dentry->d_parent->d_fsdata;
+ struct sysfs_dirent *sd;
struct inode *inode;
- int found = 0;
- for (sd = parent_sd->s_children; sd; sd = sd->s_sibling) {
- if (sysfs_type(sd) &&
- !strcmp(sd->s_name, dentry->d_name.name)) {
- found = 1;
+ mutex_lock(&sysfs_mutex);
+
+ for (sd = parent_sd->s_children; sd; sd = sd->s_sibling)
+ if (sysfs_type(sd) && !strcmp(sd->s_name, dentry->d_name.name))
break;
- }
- }
/* no such entry */
- if (!found)
- return NULL;
+ if (!sd)
+ goto out_unlock;
/* attach dentry and inode */
inode = sysfs_get_inode(sd);
- if (!inode)
- return ERR_PTR(-ENOMEM);
-
- mutex_lock(&sysfs_mutex);
-
- if (inode->i_state & I_NEW) {
- /* initialize inode according to type */
- switch (sysfs_type(sd)) {
- case SYSFS_DIR:
- inode->i_op = &sysfs_dir_inode_operations;
- inode->i_fop = &sysfs_dir_operations;
- inode->i_nlink = sysfs_count_nlink(sd);
- break;
- case SYSFS_KOBJ_ATTR:
- inode->i_size = PAGE_SIZE;
- inode->i_fop = &sysfs_file_operations;
- break;
- case SYSFS_KOBJ_BIN_ATTR:
- bin_attr = sd->s_elem.bin_attr.bin_attr;
- inode->i_size = bin_attr->size;
- inode->i_fop = &bin_fops;
- break;
- case SYSFS_KOBJ_LINK:
- inode->i_op = &sysfs_symlink_inode_operations;
- break;
- default:
- BUG();
- }
+ if (!inode) {
+ ret = ERR_PTR(-ENOMEM);
+ goto out_unlock;
}
- sysfs_instantiate(dentry, inode);
+ d_instantiate(dentry, inode);
sysfs_attach_dentry(sd, dentry);
+ out_unlock:
mutex_unlock(&sysfs_mutex);
-
- return NULL;
+ return ret;
}
const struct inode_operations sysfs_dir_inode_operations = {
struct sysfs_addrm_cxt acxt;
sysfs_addrm_start(&acxt, sd->s_parent);
- sysfs_unlink_sibling(sd);
sysfs_remove_one(&acxt, sd);
sysfs_addrm_finish(&acxt);
}
while (*pos) {
struct sysfs_dirent *sd = *pos;
- if (sysfs_type(sd) && sysfs_type(sd) != SYSFS_DIR) {
- *pos = sd->s_sibling;
- sd->s_sibling = NULL;
+ if (sysfs_type(sd) && sysfs_type(sd) != SYSFS_DIR)
sysfs_remove_one(&acxt, sd);
- } else
+ else
pos = &(*pos)->s_sibling;
}
sysfs_addrm_finish(&acxt);
__sysfs_remove_dir(sd);
}
-int sysfs_rename_dir(struct kobject *kobj, struct sysfs_dirent *new_parent_sd,
- const char *new_name)
+int sysfs_rename_dir(struct kobject * kobj, const char *new_name)
{
- struct sysfs_dirent *sd = kobj->sd;
- struct dentry *new_parent = NULL;
+ struct sysfs_dirent *sd;
+ struct dentry *parent = NULL;
struct dentry *old_dentry = NULL, *new_dentry = NULL;
const char *dup_name = NULL;
int error;
- /* get dentries */
+ /* get the original dentry */
+ sd = kobj->sd;
old_dentry = sysfs_get_dentry(sd);
if (IS_ERR(old_dentry)) {
error = PTR_ERR(old_dentry);
goto out_dput;
}
- new_parent = sysfs_get_dentry(new_parent_sd);
- if (IS_ERR(new_parent)) {
- error = PTR_ERR(new_parent);
- goto out_dput;
- }
+ parent = old_dentry->d_parent;
- /* lock new_parent and get dentry for new name */
- mutex_lock(&new_parent->d_inode->i_mutex);
+ /* lock parent and get dentry for new name */
+ mutex_lock(&parent->d_inode->i_mutex);
- new_dentry = lookup_one_len(new_name, new_parent, strlen(new_name));
+ new_dentry = lookup_one_len(new_name, parent, strlen(new_name));
if (IS_ERR(new_dentry)) {
error = PTR_ERR(new_dentry);
goto out_unlock;
}
- /* By allowing two different directories with the same
- * d_parent we allow this routine to move between different
- * shadows of the same directory
- */
error = -EINVAL;
- if (old_dentry->d_parent->d_inode != new_parent->d_inode ||
- new_dentry->d_parent->d_inode != new_parent->d_inode ||
- old_dentry == new_dentry)
+ if (old_dentry == new_dentry)
goto out_unlock;
error = -EEXIST;
if (error)
goto out_drop;
+ mutex_lock(&sysfs_mutex);
dup_name = sd->s_name;
sd->s_name = new_name;
+ mutex_unlock(&sysfs_mutex);
- /* move under the new parent */
+ /* rename */
d_add(new_dentry, NULL);
d_move(sd->s_dentry, new_dentry);
- mutex_lock(&sysfs_mutex);
-
- sysfs_unlink_sibling(sd);
- sysfs_get(new_parent_sd);
- sysfs_put(sd->s_parent);
- sd->s_parent = new_parent_sd;
- sysfs_link_sibling(sd);
-
- mutex_unlock(&sysfs_mutex);
-
error = 0;
goto out_unlock;
out_drop:
d_drop(new_dentry);
out_unlock:
- mutex_unlock(&new_parent->d_inode->i_mutex);
+ mutex_unlock(&parent->d_inode->i_mutex);
out_dput:
kfree(dup_name);
- dput(new_parent);
dput(old_dentry);
dput(new_dentry);
return error;
goto again;
}
- new_dentry = lookup_one_len(kobj->name, new_parent, strlen(kobj->name));
+ new_dentry = lookup_one_len(kobject_name(kobj), new_parent, strlen(kobject_name(kobj)));
if (IS_ERR(new_dentry)) {
error = PTR_ERR(new_dentry);
goto out_unlock;
return offset;
}
-
-/**
- * sysfs_make_shadowed_dir - Setup so a directory can be shadowed
- * @kobj: object we're creating shadow of.
- */
-
-int sysfs_make_shadowed_dir(struct kobject *kobj,
- void * (*follow_link)(struct dentry *, struct nameidata *))
-{
- struct dentry *dentry;
- struct inode *inode;
- struct inode_operations *i_op;
-
- /* get dentry for @kobj->sd, dentry of a shadowed dir is pinned */
- dentry = sysfs_get_dentry(kobj->sd);
- if (IS_ERR(dentry))
- return PTR_ERR(dentry);
-
- inode = dentry->d_inode;
- if (inode->i_op != &sysfs_dir_inode_operations) {
- dput(dentry);
- return -EINVAL;
- }
-
- i_op = kmalloc(sizeof(*i_op), GFP_KERNEL);
- if (!i_op)
- return -ENOMEM;
-
- memcpy(i_op, &sysfs_dir_inode_operations, sizeof(*i_op));
- i_op->follow_link = follow_link;
-
- /* Locking of inode->i_op?
- * Since setting i_op is a single word write and they
- * are atomic we should be ok here.
- */
- inode->i_op = i_op;
- return 0;
-}
-
-/**
- * sysfs_create_shadow_dir - create a shadow directory for an object.
- * @kobj: object we're creating directory for.
- *
- * sysfs_make_shadowed_dir must already have been called on this
- * directory.
- */
-
-struct sysfs_dirent *sysfs_create_shadow_dir(struct kobject *kobj)
-{
- struct sysfs_dirent *parent_sd = kobj->sd->s_parent;
- struct dentry *dir, *parent, *shadow;
- struct inode *inode;
- struct sysfs_dirent *sd;
- struct sysfs_addrm_cxt acxt;
-
- dir = sysfs_get_dentry(kobj->sd);
- if (IS_ERR(dir)) {
- sd = (void *)dir;
- goto out;
- }
- parent = dir->d_parent;
-
- inode = dir->d_inode;
- sd = ERR_PTR(-EINVAL);
- if (!sysfs_is_shadowed_inode(inode))
- goto out_dput;
-
- shadow = d_alloc(parent, &dir->d_name);
- if (!shadow)
- goto nomem;
-
- sd = sysfs_new_dirent("_SHADOW_", inode->i_mode, SYSFS_DIR);
- if (!sd)
- goto nomem;
- sd->s_elem.dir.kobj = kobj;
-
- sysfs_addrm_start(&acxt, parent_sd);
-
- /* add but don't link into children list */
- sysfs_add_one(&acxt, sd);
-
- /* attach and instantiate dentry */
- sysfs_attach_dentry(sd, shadow);
- d_instantiate(shadow, igrab(inode));
- inc_nlink(inode); /* tj: synchronization? */
-
- sysfs_addrm_finish(&acxt);
-
- dget(shadow); /* Extra count - pin the dentry in core */
-
- goto out_dput;
-
- nomem:
- dput(shadow);
- sd = ERR_PTR(-ENOMEM);
- out_dput:
- dput(dir);
- out:
- return sd;
-}
-
-/**
- * sysfs_remove_shadow_dir - remove an object's directory.
- * @shadow_sd: sysfs_dirent of shadow directory
- *
- * The only thing special about this is that we remove any files in
- * the directory before we remove the directory, and we've inlined
- * what used to be sysfs_rmdir() below, instead of calling separately.
- */
-
-void sysfs_remove_shadow_dir(struct sysfs_dirent *shadow_sd)
-{
- __sysfs_remove_dir(shadow_sd);
-}
-
const struct file_operations sysfs_dir_operations = {
.open = sysfs_dir_open,
.release = sysfs_dir_close,