On Mon, Jul 08, 2019 at 11:06:33AM +1000, Stephen Rothwell wrote:
> Today's linux-next merge of the vfs tree got a conflict in:
>
> fs/nfsd/nfsctl.c
>
> between commits:
>
> e8a79fb14f6b ("nfsd: add nfsd/clients directory")
>
> from the nfsd tree and commit:
>
> 96a374a35f82 ("vfs: Convert nfsctl to use the new mount API")
I did a fetch of
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
and looked at the "master" branch and couldn't find that vfs commit. Am
I looking in the wrong place?
(I'm sure your resolution is fine, I just thought to be careful it might
be nice to run some tests on the merge.)
--b.
>
> from the vfs tree.
>
> I fixed it up (Maybe? see below) and can carry the fix as necessary.
> This is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging. You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.
>
> --
> Cheers,
> Stephen Rothwell
>
> diff --cc fs/nfsd/nfsctl.c
> index 4683ba5c69c7,bbff9c4ac49f..000000000000
> --- a/fs/nfsd/nfsctl.c
> +++ b/fs/nfsd/nfsctl.c
> @@@ -1149,201 -1148,8 +1150,201 @@@ static ssize_t write_v4_end_grace(struc
> * populating the filesystem.
> */
>
> +/* Basically copying rpc_get_inode. */
> +static struct inode *nfsd_get_inode(struct super_block *sb, umode_t mode)
> +{
> + struct inode *inode = new_inode(sb);
> + if (!inode)
> + return NULL;
> + /* Following advice from simple_fill_super documentation: */
> + inode->i_ino = iunique(sb, NFSD_MaxReserved);
> + inode->i_mode = mode;
> + inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
> + switch (mode & S_IFMT) {
> + case S_IFDIR:
> + inode->i_fop = &simple_dir_operations;
> + inode->i_op = &simple_dir_inode_operations;
> + inc_nlink(inode);
> + default:
> + break;
> + }
> + return inode;
> +}
> +
> +static int __nfsd_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
> +{
> + struct inode *inode;
> +
> + inode = nfsd_get_inode(dir->i_sb, mode);
> + if (!inode)
> + return -ENOMEM;
> + d_add(dentry, inode);
> + inc_nlink(dir);
> + fsnotify_mkdir(dir, dentry);
> + return 0;
> +}
> +
> +static struct dentry *nfsd_mkdir(struct dentry *parent, struct nfsdfs_client *ncl, char *name)
> +{
> + struct inode *dir = parent->d_inode;
> + struct dentry *dentry;
> + int ret = -ENOMEM;
> +
> + inode_lock(dir);
> + dentry = d_alloc_name(parent, name);
> + if (!dentry)
> + goto out_err;
> + ret = __nfsd_mkdir(d_inode(parent), dentry, S_IFDIR | 0600);
> + if (ret)
> + goto out_err;
> + if (ncl) {
> + d_inode(dentry)->i_private = ncl;
> + kref_get(&ncl->cl_ref);
> + }
> +out:
> + inode_unlock(dir);
> + return dentry;
> +out_err:
> + dentry = ERR_PTR(ret);
> + goto out;
> +}
> +
> +static void clear_ncl(struct inode *inode)
> +{
> + struct nfsdfs_client *ncl = inode->i_private;
> +
> + inode->i_private = NULL;
> + synchronize_rcu();
> + kref_put(&ncl->cl_ref, ncl->cl_release);
> +}
> +
> +
> +struct nfsdfs_client *__get_nfsdfs_client(struct inode *inode)
> +{
> + struct nfsdfs_client *nc = inode->i_private;
> +
> + if (nc)
> + kref_get(&nc->cl_ref);
> + return nc;
> +}
> +
> +struct nfsdfs_client *get_nfsdfs_client(struct inode *inode)
> +{
> + struct nfsdfs_client *nc;
> +
> + rcu_read_lock();
> + nc = __get_nfsdfs_client(inode);
> + rcu_read_unlock();
> + return nc;
> +}
> +/* from __rpc_unlink */
> +static void nfsdfs_remove_file(struct inode *dir, struct dentry *dentry)
> +{
> + int ret;
> +
> + clear_ncl(d_inode(dentry));
> + dget(dentry);
> + ret = simple_unlink(dir, dentry);
> + d_delete(dentry);
> + dput(dentry);
> + WARN_ON_ONCE(ret);
> +}
> +
> +static void nfsdfs_remove_files(struct dentry *root)
> +{
> + struct dentry *dentry, *tmp;
> +
> + list_for_each_entry_safe(dentry, tmp, &root->d_subdirs, d_child) {
> + if (!simple_positive(dentry)) {
> + WARN_ON_ONCE(1); /* I think this can't happen? */
> + continue;
> + }
> + nfsdfs_remove_file(d_inode(root), dentry);
> + }
> +}
> +
> +/* XXX: cut'n'paste from simple_fill_super; figure out if we could share
> + * code instead. */
> +static int nfsdfs_create_files(struct dentry *root,
> + const struct tree_descr *files)
> +{
> + struct inode *dir = d_inode(root);
> + struct inode *inode;
> + struct dentry *dentry;
> + int i;
> +
> + inode_lock(dir);
> + for (i = 0; files->name && files->name[0]; i++, files++) {
> + if (!files->name)
> + continue;
> + dentry = d_alloc_name(root, files->name);
> + if (!dentry)
> + goto out;
> + inode = nfsd_get_inode(d_inode(root)->i_sb,
> + S_IFREG | files->mode);
> + if (!inode) {
> + dput(dentry);
> + goto out;
> + }
> + inode->i_fop = files->ops;
> + inode->i_private = __get_nfsdfs_client(dir);
> + d_add(dentry, inode);
> + fsnotify_create(dir, dentry);
> + }
> + inode_unlock(dir);
> + return 0;
> +out:
> + nfsdfs_remove_files(root);
> + inode_unlock(dir);
> + return -ENOMEM;
> +}
> +
> +/* on success, returns positive number unique to that client. */
> +struct dentry *nfsd_client_mkdir(struct nfsd_net *nn,
> + struct nfsdfs_client *ncl, u32 id,
> + const struct tree_descr *files)
> +{
> + struct dentry *dentry;
> + char name[11];
> + int ret;
> +
> + sprintf(name, "%u", id);
> +
> + dentry = nfsd_mkdir(nn->nfsd_client_dir, ncl, name);
> + if (IS_ERR(dentry)) /* XXX: tossing errors? */
> + return NULL;
> + ret = nfsdfs_create_files(dentry, files);
> + if (ret) {
> + nfsd_client_rmdir(dentry);
> + return NULL;
> + }
> + return dentry;
> +}
> +
> +/* Taken from __rpc_rmdir: */
> +void nfsd_client_rmdir(struct dentry *dentry)
> +{
> + struct inode *dir = d_inode(dentry->d_parent);
> + struct inode *inode = d_inode(dentry);
> + int ret;
> +
> + inode_lock(dir);
> + nfsdfs_remove_files(dentry);
> + clear_ncl(inode);
> + dget(dentry);
> + ret = simple_rmdir(dir, dentry);
> + WARN_ON_ONCE(ret);
> + d_delete(dentry);
> + inode_unlock(dir);
> +}
> +
> - static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
> + static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc)
> {
> + struct nfsd_net *nn = net_generic(current->nsproxy->net_ns,
> + nfsd_net_id);
> + struct dentry *dentry;
> + int ret;
> +
> static const struct tree_descr nfsd_files[] = {
> [NFSD_List] = {"exports", &exports_nfsd_operations, S_IRUGO},
> [NFSD_Export_features] = {"export_features",
> @@@ -1372,23 -1178,33 +1373,39 @@@
> #endif
> /* last one */ {""}
> };
> - get_net(sb->s_fs_info);
> -
> - return simple_fill_super(sb, 0x6e667364, nfsd_files);
> + ret = simple_fill_super(sb, 0x6e667364, nfsd_files);
> + if (ret)
> + return ret;
> + dentry = nfsd_mkdir(sb->s_root, NULL, "clients");
> + if (IS_ERR(dentry))
> + return PTR_ERR(dentry);
> + nn->nfsd_client_dir = dentry;
> + return 0;
> + }
> +
> + static int nfsd_fs_get_tree(struct fs_context *fc)
> + {
> + fc->s_fs_info = get_net(fc->net_ns);
> + return vfs_get_super(fc, vfs_get_keyed_super, nfsd_fill_super);
> + }
>
> + static void nfsd_fs_free_fc(struct fs_context *fc)
> + {
> + if (fc->s_fs_info)
> + put_net(fc->s_fs_info);
> }
>
> - static struct dentry *nfsd_mount(struct file_system_type *fs_type,
> - int flags, const char *dev_name, void *data)
> + static const struct fs_context_operations nfsd_fs_context_ops = {
> + .free = nfsd_fs_free_fc,
> + .get_tree = nfsd_fs_get_tree,
> + };
> +
> + static int nfsd_init_fs_context(struct fs_context *fc)
> {
> - struct net *net = current->nsproxy->net_ns;
> - return mount_ns(fs_type, flags, data, net, net->user_ns, nfsd_fill_super);
> + put_user_ns(fc->user_ns);
> + fc->user_ns = get_user_ns(fc->net_ns->user_ns);
> + fc->ops = &nfsd_fs_context_ops;
> + return 0;
> }
>
> static void nfsd_umount(struct super_block *sb)
