linux-next: manual merge of the vfs tree with the nfsd tree

From: Stephen Rothwell
Date: Sun Jul 07 2019 - 21:06:48 EST


Hi all,

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")

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)

Attachment: pgp0TyUulH89K.pgp
Description: OpenPGP digital signature