struct kmem_cache *kernfs_node_cache, *kernfs_iattrs_cache;
-static int kernfs_sop_remount_fs(struct super_block *sb, int *flags, char *data)
-{
- struct kernfs_root *root = kernfs_info(sb)->root;
- struct kernfs_syscall_ops *scops = root->syscall_ops;
-
- if (scops && scops->remount_fs)
- return scops->remount_fs(root, flags, data);
- return 0;
-}
-
static int kernfs_sop_show_options(struct seq_file *sf, struct dentry *dentry)
{
struct kernfs_root *root = kernfs_root(kernfs_dentry_node(dentry));
.drop_inode = generic_delete_inode,
.evict_inode = kernfs_evict_inode,
- .remount_fs = kernfs_sop_remount_fs,
.show_options = kernfs_sop_show_options,
.show_path = kernfs_sop_show_path,
};
} while (true);
}
-static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
+static int kernfs_fill_super(struct super_block *sb, struct kernfs_fs_context *kfc)
{
struct kernfs_super_info *info = kernfs_info(sb);
struct inode *inode;
sb->s_iflags |= SB_I_NOEXEC | SB_I_NODEV;
sb->s_blocksize = PAGE_SIZE;
sb->s_blocksize_bits = PAGE_SHIFT;
- sb->s_magic = magic;
+ sb->s_magic = kfc->magic;
sb->s_op = &kernfs_sops;
sb->s_xattr = kernfs_xattr_handlers;
if (info->root->flags & KERNFS_ROOT_SUPPORT_EXPORTOP)
return 0;
}
-static int kernfs_test_super(struct super_block *sb, void *data)
+static int kernfs_test_super(struct super_block *sb, struct fs_context *fc)
{
struct kernfs_super_info *sb_info = kernfs_info(sb);
- struct kernfs_super_info *info = data;
+ struct kernfs_super_info *info = fc->s_fs_info;
return sb_info->root == info->root && sb_info->ns == info->ns;
}
-static int kernfs_set_super(struct super_block *sb, void *data)
+static int kernfs_set_super(struct super_block *sb, struct fs_context *fc)
{
- int error;
- error = set_anon_super(sb, data);
- if (!error)
- sb->s_fs_info = data;
- return error;
+ struct kernfs_fs_context *kfc = fc->fs_private;
+
+ kfc->ns_tag = NULL;
+ return set_anon_super_fc(sb, fc);
}
/**
}
/**
- * kernfs_mount_ns - kernfs mount helper
- * @fs_type: file_system_type of the fs being mounted
- * @flags: mount flags specified for the mount
- * @root: kernfs_root of the hierarchy being mounted
- * @magic: file system specific magic number
- * @new_sb_created: tell the caller if we allocated a new superblock
- * @ns: optional namespace tag of the mount
+ * kernfs_get_tree - kernfs filesystem access/retrieval helper
+ * @fc: The filesystem context.
*
- * This is to be called from each kernfs user's file_system_type->mount()
- * implementation, which should pass through the specified @fs_type and
- * @flags, and specify the hierarchy and namespace tag to mount via @root
- * and @ns, respectively.
- *
- * The return value can be passed to the vfs layer verbatim.
+ * This is to be called from each kernfs user's fs_context->ops->get_tree()
+ * implementation, which should set the specified ->@fs_type and ->@flags, and
+ * specify the hierarchy and namespace tag to mount via ->@root and ->@ns,
+ * respectively.
*/
-struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
- struct kernfs_root *root, unsigned long magic,
- bool *new_sb_created, const void *ns)
+int kernfs_get_tree(struct fs_context *fc)
{
+ struct kernfs_fs_context *kfc = fc->fs_private;
struct super_block *sb;
struct kernfs_super_info *info;
int error;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
- info->root = root;
- info->ns = ns;
+ info->root = kfc->root;
+ info->ns = kfc->ns_tag;
INIT_LIST_HEAD(&info->node);
- sb = sget_userns(fs_type, kernfs_test_super, kernfs_set_super, flags,
- &init_user_ns, info);
- if (IS_ERR(sb) || sb->s_fs_info != info)
- kfree(info);
+ fc->s_fs_info = info;
+ sb = sget_fc(fc, kernfs_test_super, kernfs_set_super);
if (IS_ERR(sb))
- return ERR_CAST(sb);
-
- if (new_sb_created)
- *new_sb_created = !sb->s_root;
+ return PTR_ERR(sb);
if (!sb->s_root) {
struct kernfs_super_info *info = kernfs_info(sb);
- error = kernfs_fill_super(sb, magic);
+ kfc->new_sb_created = true;
+
+ error = kernfs_fill_super(sb, kfc);
if (error) {
deactivate_locked_super(sb);
- return ERR_PTR(error);
+ return error;
}
sb->s_flags |= SB_ACTIVE;
mutex_lock(&kernfs_mutex);
- list_add(&info->node, &root->supers);
+ list_add(&info->node, &info->root->supers);
mutex_unlock(&kernfs_mutex);
}
- return dget(sb->s_root);
+ fc->root = dget(sb->s_root);
+ return 0;
+}
+
+void kernfs_free_fs_context(struct fs_context *fc)
+{
+ /* Note that we don't deal with kfc->ns_tag here. */
+ kfree(fc->s_fs_info);
+ fc->s_fs_info = NULL;
}
/**
kfree(info);
}
-/**
- * kernfs_pin_sb: try to pin the superblock associated with a kernfs_root
- * @kernfs_root: the kernfs_root in question
- * @ns: the namespace tag
- *
- * Pin the superblock so the superblock won't be destroyed in subsequent
- * operations. This can be used to block ->kill_sb() which may be useful
- * for kernfs users which dynamically manage superblocks.
- *
- * Returns NULL if there's no superblock associated to this kernfs_root, or
- * -EINVAL if the superblock is being freed.
- */
-struct super_block *kernfs_pin_sb(struct kernfs_root *root, const void *ns)
-{
- struct kernfs_super_info *info;
- struct super_block *sb = NULL;
-
- mutex_lock(&kernfs_mutex);
- list_for_each_entry(info, &root->supers, node) {
- if (info->ns == ns) {
- sb = info->sb;
- if (!atomic_inc_not_zero(&info->sb->s_active))
- sb = ERR_PTR(-EINVAL);
- break;
- }
- }
- mutex_unlock(&kernfs_mutex);
- return sb;
-}
-
void __init kernfs_init(void)
{
projects / linux-2.6-block.git / blobdiff