summaryrefslogtreecommitdiff
path: root/fs/configfs/dir.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/configfs/dir.c')
-rw-r--r--fs/configfs/dir.c222
1 files changed, 165 insertions, 57 deletions
diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c
index a7a1b218f..f419519ec 100644
--- a/fs/configfs/dir.c
+++ b/fs/configfs/dir.c
@@ -255,6 +255,12 @@ static void configfs_init_file(struct inode * inode)
inode->i_fop = &configfs_file_operations;
}
+static void configfs_init_bin_file(struct inode *inode)
+{
+ inode->i_size = 0;
+ inode->i_fop = &configfs_bin_file_operations;
+}
+
static void init_symlink(struct inode * inode)
{
inode->i_op = &configfs_symlink_inode_operations;
@@ -423,7 +429,9 @@ static int configfs_attach_attr(struct configfs_dirent * sd, struct dentry * den
spin_unlock(&configfs_dirent_lock);
error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG,
- configfs_init_file);
+ (sd->s_type & CONFIGFS_ITEM_BIN_ATTR) ?
+ configfs_init_bin_file :
+ configfs_init_file);
if (error) {
configfs_put(sd);
return error;
@@ -583,6 +591,7 @@ static int populate_attrs(struct config_item *item)
{
struct config_item_type *t = item->ci_type;
struct configfs_attribute *attr;
+ struct configfs_bin_attribute *bin_attr;
int error = 0;
int i;
@@ -594,6 +603,13 @@ static int populate_attrs(struct config_item *item)
break;
}
}
+ if (t->ct_bin_attrs) {
+ for (i = 0; (bin_attr = t->ct_bin_attrs[i]) != NULL; i++) {
+ error = configfs_create_bin_file(item, bin_attr);
+ if (error)
+ break;
+ }
+ }
if (error)
detach_attrs(item);
@@ -624,13 +640,13 @@ static void detach_groups(struct config_group *group)
child = sd->s_dentry;
- mutex_lock(&d_inode(child)->i_mutex);
+ inode_lock(d_inode(child));
configfs_detach_group(sd->s_element);
d_inode(child)->i_flags |= S_DEAD;
dont_mount(child);
- mutex_unlock(&d_inode(child)->i_mutex);
+ inode_unlock(d_inode(child));
d_delete(child);
dput(child);
@@ -818,11 +834,11 @@ static int configfs_attach_item(struct config_item *parent_item,
* the VFS may already have hit and used them. Thus,
* we must lock them as rmdir() would.
*/
- mutex_lock(&d_inode(dentry)->i_mutex);
+ inode_lock(d_inode(dentry));
configfs_remove_dir(item);
d_inode(dentry)->i_flags |= S_DEAD;
dont_mount(dentry);
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
d_delete(dentry);
}
}
@@ -858,7 +874,7 @@ static int configfs_attach_group(struct config_item *parent_item,
* We must also lock the inode to remove it safely in case of
* error, as rmdir() would.
*/
- mutex_lock_nested(&d_inode(dentry)->i_mutex, I_MUTEX_CHILD);
+ inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD);
configfs_adjust_dir_dirent_depth_before_populate(sd);
ret = populate_groups(to_config_group(item));
if (ret) {
@@ -867,7 +883,7 @@ static int configfs_attach_group(struct config_item *parent_item,
dont_mount(dentry);
}
configfs_adjust_dir_dirent_depth_after_populate(sd);
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
if (ret)
d_delete(dentry);
}
@@ -1054,11 +1070,55 @@ out:
return ret;
}
+static int configfs_do_depend_item(struct dentry *subsys_dentry,
+ struct config_item *target)
+{
+ struct configfs_dirent *p;
+ int ret;
+
+ spin_lock(&configfs_dirent_lock);
+ /* Scan the tree, return 0 if found */
+ ret = configfs_depend_prep(subsys_dentry, target);
+ if (ret)
+ goto out_unlock_dirent_lock;
+
+ /*
+ * We are sure that the item is not about to be removed by rmdir(), and
+ * not in the middle of attachment by mkdir().
+ */
+ p = target->ci_dentry->d_fsdata;
+ p->s_dependent_count += 1;
+
+out_unlock_dirent_lock:
+ spin_unlock(&configfs_dirent_lock);
+
+ return ret;
+}
+
+static inline struct configfs_dirent *
+configfs_find_subsys_dentry(struct configfs_dirent *root_sd,
+ struct config_item *subsys_item)
+{
+ struct configfs_dirent *p;
+ struct configfs_dirent *ret = NULL;
+
+ list_for_each_entry(p, &root_sd->s_children, s_sibling) {
+ if (p->s_type & CONFIGFS_DIR &&
+ p->s_element == subsys_item) {
+ ret = p;
+ break;
+ }
+ }
+
+ return ret;
+}
+
+
int configfs_depend_item(struct configfs_subsystem *subsys,
struct config_item *target)
{
int ret;
- struct configfs_dirent *p, *root_sd, *subsys_sd = NULL;
+ struct configfs_dirent *subsys_sd;
struct config_item *s_item = &subsys->su_group.cg_item;
struct dentry *root;
@@ -1075,43 +1135,19 @@ int configfs_depend_item(struct configfs_subsystem *subsys,
* subsystem is really registered, and so we need to lock out
* configfs_[un]register_subsystem().
*/
- mutex_lock(&d_inode(root)->i_mutex);
-
- root_sd = root->d_fsdata;
-
- list_for_each_entry(p, &root_sd->s_children, s_sibling) {
- if (p->s_type & CONFIGFS_DIR) {
- if (p->s_element == s_item) {
- subsys_sd = p;
- break;
- }
- }
- }
+ inode_lock(d_inode(root));
+ subsys_sd = configfs_find_subsys_dentry(root->d_fsdata, s_item);
if (!subsys_sd) {
ret = -ENOENT;
goto out_unlock_fs;
}
/* Ok, now we can trust subsys/s_item */
+ ret = configfs_do_depend_item(subsys_sd->s_dentry, target);
- spin_lock(&configfs_dirent_lock);
- /* Scan the tree, return 0 if found */
- ret = configfs_depend_prep(subsys_sd->s_dentry, target);
- if (ret)
- goto out_unlock_dirent_lock;
-
- /*
- * We are sure that the item is not about to be removed by rmdir(), and
- * not in the middle of attachment by mkdir().
- */
- p = target->ci_dentry->d_fsdata;
- p->s_dependent_count += 1;
-
-out_unlock_dirent_lock:
- spin_unlock(&configfs_dirent_lock);
out_unlock_fs:
- mutex_unlock(&d_inode(root)->i_mutex);
+ inode_unlock(d_inode(root));
/*
* If we succeeded, the fs is pinned via other methods. If not,
@@ -1128,8 +1164,7 @@ EXPORT_SYMBOL(configfs_depend_item);
* configfs_depend_item() because we know that that the client driver is
* pinned, thus the subsystem is pinned, and therefore configfs is pinned.
*/
-void configfs_undepend_item(struct configfs_subsystem *subsys,
- struct config_item *target)
+void configfs_undepend_item(struct config_item *target)
{
struct configfs_dirent *sd;
@@ -1152,6 +1187,79 @@ void configfs_undepend_item(struct configfs_subsystem *subsys,
}
EXPORT_SYMBOL(configfs_undepend_item);
+/*
+ * caller_subsys is a caller's subsystem not target's. This is used to
+ * determine if we should lock root and check subsys or not. When we are
+ * in the same subsystem as our target there is no need to do locking as
+ * we know that subsys is valid and is not unregistered during this function
+ * as we are called from callback of one of his children and VFS holds a lock
+ * on some inode. Otherwise we have to lock our root to ensure that target's
+ * subsystem it is not unregistered during this function.
+ */
+int configfs_depend_item_unlocked(struct configfs_subsystem *caller_subsys,
+ struct config_item *target)
+{
+ struct configfs_subsystem *target_subsys;
+ struct config_group *root, *parent;
+ struct configfs_dirent *subsys_sd;
+ int ret = -ENOENT;
+
+ /* Disallow this function for configfs root */
+ if (configfs_is_root(target))
+ return -EINVAL;
+
+ parent = target->ci_group;
+ /*
+ * This may happen when someone is trying to depend root
+ * directory of some subsystem
+ */
+ if (configfs_is_root(&parent->cg_item)) {
+ target_subsys = to_configfs_subsystem(to_config_group(target));
+ root = parent;
+ } else {
+ target_subsys = parent->cg_subsys;
+ /* Find a cofnigfs root as we may need it for locking */
+ for (root = parent; !configfs_is_root(&root->cg_item);
+ root = root->cg_item.ci_group)
+ ;
+ }
+
+ if (target_subsys != caller_subsys) {
+ /*
+ * We are in other configfs subsystem, so we have to do
+ * additional locking to prevent other subsystem from being
+ * unregistered
+ */
+ inode_lock(d_inode(root->cg_item.ci_dentry));
+
+ /*
+ * As we are trying to depend item from other subsystem
+ * we have to check if this subsystem is still registered
+ */
+ subsys_sd = configfs_find_subsys_dentry(
+ root->cg_item.ci_dentry->d_fsdata,
+ &target_subsys->su_group.cg_item);
+ if (!subsys_sd)
+ goto out_root_unlock;
+ } else {
+ subsys_sd = target_subsys->su_group.cg_item.ci_dentry->d_fsdata;
+ }
+
+ /* Now we can execute core of depend item */
+ ret = configfs_do_depend_item(subsys_sd->s_dentry, target);
+
+ if (target_subsys != caller_subsys)
+out_root_unlock:
+ /*
+ * We were called from subsystem other than our target so we
+ * took some locks so now it's time to release them
+ */
+ inode_unlock(d_inode(root->cg_item.ci_dentry));
+
+ return ret;
+}
+EXPORT_SYMBOL(configfs_depend_item_unlocked);
+
static int configfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
{
int ret = 0;
@@ -1453,7 +1561,7 @@ int configfs_rename_dir(struct config_item * item, const char *new_name)
down_write(&configfs_rename_sem);
parent = item->parent->dentry;
- mutex_lock(&d_inode(parent)->i_mutex);
+ inode_lock(d_inode(parent));
new_dentry = lookup_one_len(new_name, parent, strlen(new_name));
if (!IS_ERR(new_dentry)) {
@@ -1469,7 +1577,7 @@ int configfs_rename_dir(struct config_item * item, const char *new_name)
error = -EEXIST;
dput(new_dentry);
}
- mutex_unlock(&d_inode(parent)->i_mutex);
+ inode_unlock(d_inode(parent));
up_write(&configfs_rename_sem);
return error;
@@ -1482,7 +1590,7 @@ static int configfs_dir_open(struct inode *inode, struct file *file)
struct configfs_dirent * parent_sd = dentry->d_fsdata;
int err;
- mutex_lock(&d_inode(dentry)->i_mutex);
+ inode_lock(d_inode(dentry));
/*
* Fake invisibility if dir belongs to a group/default groups hierarchy
* being attached
@@ -1495,7 +1603,7 @@ static int configfs_dir_open(struct inode *inode, struct file *file)
else
err = 0;
}
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
return err;
}
@@ -1505,11 +1613,11 @@ static int configfs_dir_close(struct inode *inode, struct file *file)
struct dentry * dentry = file->f_path.dentry;
struct configfs_dirent * cursor = file->private_data;
- mutex_lock(&d_inode(dentry)->i_mutex);
+ inode_lock(d_inode(dentry));
spin_lock(&configfs_dirent_lock);
list_del_init(&cursor->s_sibling);
spin_unlock(&configfs_dirent_lock);
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
release_configfs_dirent(cursor);
@@ -1590,7 +1698,7 @@ static loff_t configfs_dir_lseek(struct file *file, loff_t offset, int whence)
{
struct dentry * dentry = file->f_path.dentry;
- mutex_lock(&d_inode(dentry)->i_mutex);
+ inode_lock(d_inode(dentry));
switch (whence) {
case 1:
offset += file->f_pos;
@@ -1598,7 +1706,7 @@ static loff_t configfs_dir_lseek(struct file *file, loff_t offset, int whence)
if (offset >= 0)
break;
default:
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
return -EINVAL;
}
if (offset != file->f_pos) {
@@ -1624,7 +1732,7 @@ static loff_t configfs_dir_lseek(struct file *file, loff_t offset, int whence)
spin_unlock(&configfs_dirent_lock);
}
}
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
return offset;
}
@@ -1659,14 +1767,14 @@ int configfs_register_group(struct config_group *parent_group,
parent = parent_group->cg_item.ci_dentry;
- mutex_lock_nested(&d_inode(parent)->i_mutex, I_MUTEX_PARENT);
+ inode_lock_nested(d_inode(parent), I_MUTEX_PARENT);
ret = create_default_group(parent_group, group);
if (!ret) {
spin_lock(&configfs_dirent_lock);
configfs_dir_set_ready(group->cg_item.ci_dentry->d_fsdata);
spin_unlock(&configfs_dirent_lock);
}
- mutex_unlock(&d_inode(parent)->i_mutex);
+ inode_unlock(d_inode(parent));
return ret;
}
EXPORT_SYMBOL(configfs_register_group);
@@ -1683,7 +1791,7 @@ void configfs_unregister_group(struct config_group *group)
struct dentry *dentry = group->cg_item.ci_dentry;
struct dentry *parent = group->cg_item.ci_parent->ci_dentry;
- mutex_lock_nested(&d_inode(parent)->i_mutex, I_MUTEX_PARENT);
+ inode_lock_nested(d_inode(parent), I_MUTEX_PARENT);
spin_lock(&configfs_dirent_lock);
configfs_detach_prep(dentry, NULL);
spin_unlock(&configfs_dirent_lock);
@@ -1692,7 +1800,7 @@ void configfs_unregister_group(struct config_group *group)
d_inode(dentry)->i_flags |= S_DEAD;
dont_mount(dentry);
d_delete(dentry);
- mutex_unlock(&d_inode(parent)->i_mutex);
+ inode_unlock(d_inode(parent));
dput(dentry);
@@ -1764,7 +1872,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
sd = root->d_fsdata;
link_group(to_config_group(sd->s_element), group);
- mutex_lock_nested(&d_inode(root)->i_mutex, I_MUTEX_PARENT);
+ inode_lock_nested(d_inode(root), I_MUTEX_PARENT);
err = -ENOMEM;
dentry = d_alloc_name(root, group->cg_item.ci_name);
@@ -1784,7 +1892,7 @@ int configfs_register_subsystem(struct configfs_subsystem *subsys)
}
}
- mutex_unlock(&d_inode(root)->i_mutex);
+ inode_unlock(d_inode(root));
if (err) {
unlink_group(group);
@@ -1805,9 +1913,9 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
return;
}
- mutex_lock_nested(&d_inode(root)->i_mutex,
+ inode_lock_nested(d_inode(root),
I_MUTEX_PARENT);
- mutex_lock_nested(&d_inode(dentry)->i_mutex, I_MUTEX_CHILD);
+ inode_lock_nested(d_inode(dentry), I_MUTEX_CHILD);
mutex_lock(&configfs_symlink_mutex);
spin_lock(&configfs_dirent_lock);
if (configfs_detach_prep(dentry, NULL)) {
@@ -1818,11 +1926,11 @@ void configfs_unregister_subsystem(struct configfs_subsystem *subsys)
configfs_detach_group(&group->cg_item);
d_inode(dentry)->i_flags |= S_DEAD;
dont_mount(dentry);
- mutex_unlock(&d_inode(dentry)->i_mutex);
+ inode_unlock(d_inode(dentry));
d_delete(dentry);
- mutex_unlock(&d_inode(root)->i_mutex);
+ inode_unlock(d_inode(root));
dput(dentry);